The purpose of this study was to evaluate the roles of different housing environments in neurological function, cerebral metabolism, cerebral infarction and neuron apoptosis after focal cerebral ischemia. Twenty-eight...The purpose of this study was to evaluate the roles of different housing environments in neurological function, cerebral metabolism, cerebral infarction and neuron apoptosis after focal cerebral ischemia. Twenty-eight Sprague-Dawley rats were divided into control group （CG） and cerebral ischemia group, and the latter was further divided into subgroups of different housing conditions： standard environment （SE） subgroup, individual living environment （IE） subgroup, and enriched environment （EE） subgroup. Focal cerebral ischemia was induced by the middle cerebral artery occlusion （MCAO）. Beam walking test was used to quantify the changes of overall motor function. Cerebral infarction and cerebral metabolism were studied by in vivo magnetic resonance imaging and 1H-magnetic resonance spectra, respectively. Neuron necrosis and apoptosis were detected by hematoxylin-eosin and TUNEL staining methods, respectively. The results showed that performance on the beam-walk test was improved in EE subgroup when compared to SE subgroup and IE subgroup. Cerebral infarct volume in IE subgroup was significantly larger than that in SE subgroup （P〈0.05） and EE subgroup （P〈0.05） on day 14 after MCAO. NAA/Cr and Cho/Cr ratios were lower in MCAO groups under different housing conditions as compared to those in CG （P〈0.05）. NAA/Cr ratio was lower in IE subgroup （P〈0.05） and higher in EE subgroup （P〈0.05） than that in SE subgroup. NAA/ Cr ratio in EE was significantly higher than that in IE subgroup （P〈0.05）. Cho/Cr ratio was decreased in MCAO groups as compared to that in CG （P〈0.05）. A significant decrease in normal neurons in cerebral cortex was observed in MCAO groups as compared to CG （P〈0.05）. The amount of normal neurons was less in IE subgroup （P〈0.05）, and more in EE subgroup （P〈0.05） than that in SE subgroup after MCAO. The amotmt of normal neurons in EE subgroup was significantly more than that in IE subgroup after MCAO （P〈0.05）. The ratio of TUNEL-positive neurons in EE was significantly lower than that in SE subgroup （P〈0.05） and IE subgroup （P〈0.05）. Correlation analysis showed that the beam walking test was negatively correlated with NAA/Cr ratio （P〈0.05）. Cerebral infarct volume was negatively correlated with both NAA/Cr ratio （P〈0.01） and Cho/Cr ratio （P〈0.01）. The amount of normal cortical neurons was positively correlated with both NAA/Cr ratio （P〈0.0I） and Cho/Cr ratio （P〈0.05）. The TUNEL-positive neurons showed a negative correlation with both NAA/Cr ratio （P〈0.01） and Cho/Cr ratio （P〈0.01）. This study goes further to show that EE may improve neurological functional deficit and cerebral metabolism, decrease cerebral infarct volume, neuron necrosis and apoptosis, while IE may aggravate brain damage after MCAO.展开更多
BACKGROUND Spinal cord injury(SCI)is a severe and permanent trauma that often leads to significant motor,sensory,and autonomic dysfunction.Neuronal apoptosis is a major pathomechanism underlying secondary injury in SC...BACKGROUND Spinal cord injury(SCI)is a severe and permanent trauma that often leads to significant motor,sensory,and autonomic dysfunction.Neuronal apoptosis is a major pathomechanism underlying secondary injury in SCI.Long non-coding RNAs(lncRNAs)have emerged as key regulators of gene expression and cellular processes,including apoptosis.However,the role of lncRNA growth arrest-specific transcript 5(GAS5)in SCI-induced neuronal apoptosis remains unclear.AIM To investigate the role of lncRNA GAS5 in SCI-induced neuronal apoptosis via its interaction with microRNA(miR)-21 and the phosphatase and tensin homolog(PTEN)/AKT pathway.METHODS SCI rat models and hypoxic neuronal cell models were established.Motor function was assessed using the Basso-Beattie-Bresnahan score.Expression levels of GAS5,miR-21,PTEN,caspase 3,B-cell lymphoma 2(Bcl-2),Bcl-2-associated X protein(Bax),and AKT were measured using quantitative PCR or Western blot analysis.Neuronal apoptosis was determined by TUNEL staining.Dual-luciferase reporter assays validated GAS5-miR-21 binding.Knockdown and overexpression experiments explored the functional effects of the GAS5/miR-21 axis.RESULTS GAS5 was significantly upregulated in the spinal cord following SCI,coinciding with increased neuronal apoptosis and decreased AKT activation.In vitro experiments demonstrated that GAS5 acted as a molecular sponge for miR-21,leading to increased PTEN expression and inhibition of the AKT signaling pathway,thereby promoting apoptosis.In vivo,GAS5 knockdown attenuated neuronal apoptosis,enhanced AKT activation,and improved motor function recovery in SCI rats.CONCLUSION GAS5 promotes neuronal apoptosis in SCI by binding to miR-21 and upregulating PTEN expression,inhibiting the AKT pathway.Targeting GAS5 may represent a novel therapeutic strategy for SCI.展开更多
Indicaxanthin is a betalain that is abundant in Opuntia ficus-indica orange fruit and has antioxidative and anti-inflammatory effects. Nevertheless, very little is known about the neuroprotective potential of indicaxa...Indicaxanthin is a betalain that is abundant in Opuntia ficus-indica orange fruit and has antioxidative and anti-inflammatory effects. Nevertheless, very little is known about the neuroprotective potential of indicaxanthin. This study investigated the impact of indicaxanthin on neuronal damage and gut microbiota dysbiosis induced by a high-fat diet in mice. The mice were divided into three groups according to different diets: the negative control group was fed a standard diet;the high-fat diet group was fed a high-fat diet;and the high-fat diet + indicaxanthin group was fed a high-fat diet and received indicaxanthin orally(0.86 mg/kg per day) for 4 weeks. Brain apoptosis, redox status, inflammation, and the gut microbiota composition were compared among the different animal groups. The results demonstrated that indicaxanthin treatment reduced neuronal apoptosis by downregulating the expression of proapoptotic genes and increasing the expression of antiapoptotic genes. Indicaxanthin also markedly decreased the expression of neuroinflammatory proteins and genes and inhibited high-fat diet–induced neuronal oxidative stress by reducing reactive oxygen and nitrogen species, malondialdehyde, and nitric oxide levels. In addition, indicaxanthin treatment improved the microflora composition by increasing the abundance of healthy bacterial genera, known as producers of short-chain fatty acids(Lachnospiraceae, Alloprovetella, and Lactobacillus), and by reducing bacteria related to unhealthy profiles(Blautia, Faecalibaculum, Romboutsia and Bilophila). In conclusion, indicaxanthin has a positive effect on high-fat diet–induced neuronal damage and on the gut microbiota composition in obese mice.展开更多
Objective Cerebral ischemia/reperfusion(I/R)is a potential factor for lethal injury,and currently lacks effective remedies.Bauhinia championii extracts(BCEs)have been reported to exhibit anti-oxidative and anti-hypoxi...Objective Cerebral ischemia/reperfusion(I/R)is a potential factor for lethal injury,and currently lacks effective remedies.Bauhinia championii extracts(BCEs)have been reported to exhibit anti-oxidative and anti-hypoxia properties.The current work aimed to study whether BCE could alleviate neuronal injury caused by I/R.Methods To investigate the protective effects of BCE,oxygen-glucose deprivation/reperfusion(OGD/R)was applied to the HT22 cell line in vitro and to a cerebral I/R mouse model in vivo.Results Under OGD/R,the survival of HT22 cells was significantly prolonged after treatment with BCE.In vivo,BCE significantly reduced the infarct area and decreased neuronal apoptosis caused by I/R.It was further found that OGD/R could trigger endoplasmic reticulum(ER)stress and induce ER stress-mediated neuronal apoptosis in vivo and in vitro,while BCE could effectively alleviate ER stress and neuronal apoptosis.Conclusion These results suggested that BCE exhibits neuroprotective effects by reducing ER stress-mediated apoptosis after cerebral I/R injury.BCE may therefore be an effective therapeutic regimen against cerebral I/R damage.展开更多
Subarachnoid hemorrhage(SAH)is a dominant cause of death and disability wo rldwide.A sharp increase in intracranial pressure after SAH leads to a reduction in cerebral perfusion and insufficient blood supply for neuro...Subarachnoid hemorrhage(SAH)is a dominant cause of death and disability wo rldwide.A sharp increase in intracranial pressure after SAH leads to a reduction in cerebral perfusion and insufficient blood supply for neuro ns,which subsequently promotes a series of pathophysiological responses leading to neuronal death.Many previous experimental studies have reported that excitotoxicity,mitochondrial death pathways,the release of free radicals,protein misfolding,apoptosis,nec rosis,autophagy,and inflammation are involved solely or in combination in this disorder.Among them,irreversible neuronal apoptosis plays a key role in both short-and long-term prognoses after SAH.Neuronal apoptosis occurs through multiple pathways including extrinsic,mitochondrial,endoplasmic reticulum,p53 and oxidative stress.Meanwhile,a large number of blood contents enter the subarachnoid space after SAH,and the secondary metabolites,including oxygenated hemoglo bin and heme,further aggravate the destruction of the blood-brain barrier and vasogenic and cytotoxic brain edema,causing early brain injury and delayed cerebral ischemia,and ultimately increasing neuronal apoptosis.Even there is no clear and effective therapeutic strategy for SAH thus far,but by understanding apoptosis,we might excavate new ideas and approaches,as targeting the upstream and downstream molecules of apoptosis-related pathways shows promise in the treatment of SAH.In this review,we summarize the existing evidence on molecules and related drugs or molecules involved in the apoptotic pathway after SAH,which provides a possible target or new strategy for the treatment of SAH.展开更多
Urolithin A(UA)is a natural metabolite produced from polyphenolics in foods such as pomegranates,berries,and nuts.UA is neuroprotective against Parkinson’s disease,Alzheimer’s disease,and cerebral hemorrhage.However...Urolithin A(UA)is a natural metabolite produced from polyphenolics in foods such as pomegranates,berries,and nuts.UA is neuroprotective against Parkinson’s disease,Alzheimer’s disease,and cerebral hemorrhage.However,its effect against traumatic brain injury remains unknown.In this study,we established adult C57BL/6J mouse models of traumatic brain injury by controlled cortical impact and then intraperitoneally administered UA.We found that UA greatly reduced brain edema;increased the expression of tight junction proteins in injured cortex;increased the immunopositivity of two neuronal autophagy markers,microtubule-associated protein 1A/B light chain 3A/B(LC3)and p62;downregulated protein kinase B(Akt)and mammalian target of rapamycin(mTOR),two regulators of the phosphatidylinositol 3-kinase(PI3K)/Akt/mTOR signaling pathway;decreased the phosphorylation levels of inhibitor of NFκB(IκB)kinase alpha(IKKα)and nuclear factor kappa B(NFκB),two regulators of the neuroinflammation-related Akt/IKK/NFκB signaling pathway;reduced blood-brain barrier permeability and neuronal apoptosis in injured cortex;and improved mouse neurological function.These findings suggest that UA may be a candidate drug for the treatment of traumatic brain injury,and its neuroprotective effects may be mediated by inhibition of the PI3K/Akt/mTOR and Akt/IKK/NFκB signaling pathways,thus reducing neuroinflammation and enhancing autophagy.展开更多
Neuronal apoptosis is one of the essential mechanisms of early brain injury after subarachnoid hemorrhage(SAH).Recently,HLY78 has been shown to inhibit apoptosis in tumor cells and embryonic cells c aused by carbon io...Neuronal apoptosis is one of the essential mechanisms of early brain injury after subarachnoid hemorrhage(SAH).Recently,HLY78 has been shown to inhibit apoptosis in tumor cells and embryonic cells c aused by carbon ion radiation through activation of the Wnt/β-catenin pathway.This study was designed to explore the anti-apoptotic role of HLY78 in experimental SAH.The results demonstrated that HLY78 attenuated neuronal apoptosis and the neurological deficits after SAH through the activation of low-density lipoprotein receptor-related protein 6(LRP6),which subsequently increased the level of phosphorylated glycogen synthesis kinase 3 beta(p-GSK3β)(Ser9),β-catenin,and Bcl-2,accompanied by a decrease of p-β-catenin,Bax,and cleaved caspase 3.An LRP6 small-interfering ribonucleic acid reversed the effects of HLY78.In conclusion,HLY78 attenuates neuronal apoptosis and improves neurological deficits through the LRP6/GSK3β/β-catenin signaling pathway after SAH in rats.HLY78 is a promising therapeutic agent to attenuate early brain injury after SAH.展开更多
Apoptosis in cultured rat hippocampal neurons was induced using the nitric oxide donor 3-morpholinosydnonimine, and cells were treated with the chloride channel blocker, 4,4- diisothiocyanatostilbene-2,2＇-disulfonic ...Apoptosis in cultured rat hippocampal neurons was induced using the nitric oxide donor 3-morpholinosydnonimine, and cells were treated with the chloride channel blocker, 4,4- diisothiocyanatostilbene-2,2＇-disulfonic acid. Results showed that the survival rate of neurons was significantly increased after treatment with 4,4-diisothiocyanatostilbene-2,2＇-disulfonic acid, and the rate of apoptosis decreased. In addition, the expression of the apoptosis-related proteins poly（adenosine diphosphate-ribose）polymerase-1 and apoptosis-inducing factor were significantly reduced. Our experimental findings indicate that the chloride channel blocker 4,4- diisothiocyanatostilbene-2,2＇-disulfonic acid can antagonize apoptotic cell death of hippocampal neurons by inhibiting the expression of the apoptosis-related proteins poly（adenosine diphosphate-ribose）polymerase-1 and apoptosis-inducing factor.展开更多
Epidemiological studies have shown that particulate matter 2.5（PM（2.5）） not only increases the incidence of cardiopulmonary illnesses but also relates to the development of neurodegenerative diseases. Considering ...Epidemiological studies have shown that particulate matter 2.5（PM（2.5）） not only increases the incidence of cardiopulmonary illnesses but also relates to the development of neurodegenerative diseases. Considering that PM（2.5）is highly heterogeneous with regional disparity and seasonal variation, we investigated whether PM（2.5）exposure induced neuronal apoptosis and synaptic injuries in a season-dependent manner. The results indicated that PM（2.5）altered the expression of apoptosis-related proteins（mainly bax and bcl-2）, activated caspase-3 and caused neuronal apoptosis. Additionally, PM（2.5）decreased the levels of synaptic structural protein postsynaptic density（PSD-95） and synaptic functional protein N-methyl-D-aspartate（NMDA） receptor subunit（NR2B） expression. These effects occurred in a season-dependent manner, and PM（2.5）collected from the winter showed the strongest changes. Furthermore, the effect was coupled with the inhibition of phosphorylated extracellular signal-regulated kinase 1/2（p-ERK1/2） and phosphorylated c AMP-response element binding protein（p-CREB）. Based on the findings, we analyzed the correlations between the chemical composition of PM（2.5）samples and the biological effects, and confirmed that winter PM（2.5）played a major role in causing neuronal apoptosis and synaptic injuries among different season samples.展开更多
BACKGROUND： Apoptosis plays an important role in central neural diseases and trauma. B-cell lymphoma/Leukemia-2 （Bcl-2） can inhibit apoptosis in a wide variety of cells including neurons. In this experiment, by stu...BACKGROUND： Apoptosis plays an important role in central neural diseases and trauma. B-cell lymphoma/Leukemia-2 （Bcl-2） can inhibit apoptosis in a wide variety of cells including neurons. In this experiment, by studying Bcl-2 over-expression transgenic （TG） mice subjected to spinal cord injury （SCI）, we investigated whether Bcl-2 could reduce posttraumatic neuronal apoptosis, reduce the range of damage, and improve the behavioral functional recovery after contusive SCI.METHODS： Nine Bcl-2 TG mice and nine control mice were subjected to SCI of moderate severity at T10, with the use of weight dropping （WD） method （impact force 2.5×3.0 g/cm）. At times up to 1 day, 7 days and 14 days after SCI, functional defi cits were evaluated with Basso, Beattie, and Bresnahan （BBB） scales, and apoptosis of neurons was investigated by using the TUNEL method. Another three control mice only underwent lamina opening, but were not subjected to SCI, to provide blank comparison.RESULTS： The mean functional scores for the control mice （5.05 ±0.35） were lower than those for the Bcl-2 TG mice （5.45 ±0.15）, although the unpaired T-test revealed no signifi cant difference （P=0.67）. On the other hand, the number of TUNEL positive neurons and integrated option density （IOD） scores for the Bcl-2 TG mice were both signifi cantly lower than those for the control mice （P〈0.05）.CONCLUSIONS： This experiment suggests that overexpression of Bcl-2 may suppress neuronal apoptosis after SCI. Bcl-2 may be an important factor within the central nervous system that can relieve the damage after trauma.展开更多
Programmed cell death （PCD） signaling pathways are import- ant contributors to acute neurological insults such as hypox- ic-ischemic brain damage, traumatic brain injury, stroke etc. The pathogenesis of all these di...Programmed cell death （PCD） signaling pathways are import- ant contributors to acute neurological insults such as hypox- ic-ischemic brain damage, traumatic brain injury, stroke etc. The pathogenesis of all these diseases is closely linked with ab- erration of apoptotic cell death pathways. Mitochondria play a crucial role during PCD, acting as both sensors of death signals, and as initiators of biochemical path- ways, which cause cell death （Bras et al., 2005）. Cytochrome c was the firstly identified apoptogenic factor released from mitochondria into the cytosol, where it induces apoptosome formation through the activation of caspases. Other proteins, such as apoptosis inducing factor （AIF）, have been subsequently identified as mitochondrial released factors. AIF contributes to apoptotic nuclear DNA damage （Bras et al., 2005）. in a caspase-independent way展开更多
Ischemic stroke is most commonly caused by vascular occlusion due to thrombosis or arterial embolism. Recently, thrombolysis has been used with increasing frequency for the treatment of acute ischemic stroke. Among th...Ischemic stroke is most commonly caused by vascular occlusion due to thrombosis or arterial embolism. Recently, thrombolysis has been used with increasing frequency for the treatment of acute ischemic stroke. Among the drugs used for thrombolysis, only recombinant tissue plasminogen activator is widely accepted internationally （Albers et al., 2008）. In China, urokinase has been widely used for thrombolysis after acute ischemic stroke. Pro-uro- kinase is the precursor of urokinase. Compared with urokinase, pro-uroki- nase has greater ability to dissolve thrombus and is safer to use.展开更多
BACKGROUND： The neuroprotective effects of （-）-epigallocatechin-3-gallate （EGCG）, the main polyphenolic constituent of green tea, have been widely reported. However, the action mechanisms, in particular in D-gala...BACKGROUND： The neuroprotective effects of （-）-epigallocatechin-3-gallate （EGCG）, the main polyphenolic constituent of green tea, have been widely reported. However, the action mechanisms, in particular in D-galactose-induced aging mice, remain poorly understood. OBJECTIVE： The present study investigated the protective effects of EGCG on D-galactose-induced hippocampus neuronal apoptosis in aging mice, as well as the relationship with expression of p751CD, JNK2, and p53 proteins. DESIGN, TIME AND SETTING： A randomized, controlled, molecular biological, animal experiment was performed at the Laboratory of Pharmacology, Pharmaceutical College of China Medical University, China, from September 2006 to July 2008. MATERIALS： D-galactose and EGCG （Sigma, USA）, as well as terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling （TUNEL） In Situ Cell Apoptosis Detection Kit （Promega, USA）, were used in this study. METHODS： A total of 64 mice were equally and randomly divided into D-galactose model, low-dose EGCG, high-dose EGCG, and control groups. Mice in the D-galactose model, low-dose EGCG, and high-dose EGCG groups were subcutaneously injected with 3% D-galactose （150 mg/kg）, daily for 6 weeks, to establish a mouse model of aging. Mice in the control group were treated with saline （5 mL/kg）. At 3 weeks following injection, mice in the low-dose EGCG and high-dose EGCG groups were orally administered EGCG at a dose of 2 mg/kg and 6 mg/kg, respectively, once a day, for 4 consecutive days. Mice in the control and D-galactose model groups received distilled water （5 mL/kg）. MAIN OUTCOME MEASURES： Memory function was evaluated using a step-through passive avoidance test. Neuronal apoptosis in the mouse hippocampus was detected using TUNEL staining. Expression levels of the intracellular domain of the p75 neurotrophin receptor （p75NTR）-p751CD, JNK2, and p53 proteins in the hippocampus were determined using Western blot analysis. RESULTS： The aging mouse model was induced by subcutaneous injection of D-galactose, which resulted in obvious memory impairment, increased apoptotic index, and increased protein expression levels of p751CD, JNK2, and p53 in the hippocampus, compared with control mice （P 〈 0.01）. Oral EGCG administration （2 or 6 mg/kg） for 4 weeks significantly improved levels of memory deficit in the aging mice and reduced apoptotic indices and protein expression levels of p751CD, JNK2, and p53 in the mouse hippocampus （P 〈 0.01）. CONCLUSION： Results from this study demonstrated increased protein expression levels of p751CD, JNK2, and p53, as well as increased hippocampal neuronal apoptosis in a D-galactose-induced mouse model of aging. EGCG provided protective effects against D-galactose-induced neuronal apoptosis in the hippocampus by reducing protein expression levels of p751CD, JNK2, and p53 proteins in the hippocampus of aging mice.展开更多
Objective:Based on the BDNF/TrkB/CREB pathway,to explore the mechanism of neuronal apoptosis and brain developmental injury in the hippocampus of hypoxic-ischemic neonatal rats.Methods:Wistar young rats were ligated o...Objective:Based on the BDNF/TrkB/CREB pathway,to explore the mechanism of neuronal apoptosis and brain developmental injury in the hippocampus of hypoxic-ischemic neonatal rats.Methods:Wistar young rats were ligated on one side of the common carotid artery and placed in an 8%oxygen and 92%nitrogen hypoxia box for 2 h to prepare hypoxic-ischemic brain injury models.Healthy rats were used as the control group.Control group and model group were selected,with 10 rats in each group,and the learning and memory ability was tested by Y-maze;2,3,5-triphenyltetrazolium chloride(TTC)staining was used to detect brain tissue damage;Western blot was performed to determine the expression of brain-derived neurotrophic factor(BDNF),tyrosine protein kinase B(TrKB)and cAMP-response element binding protein(CREB)in hippocampal tissue.Another 15 mice in the control group and 60 mice in the model group were divided into negative control group(NC),BDNF overexpression group(LV-BDNF),TrkB overexpression group(LV-TrkB),and CREB overexpression group(LV-CREB),blank vector,BDNF,TrkB,CREB adenovirus overexpression vector was injected into the tail vein.Y-maze test for learning and memory ability;TTC staining method to detect brain tissue damage;neuronal apoptosis in the hippocampus were detected by terminal-deoxynucleoitidyl transferase mediated nick end labeling;Western blot to detect the level of neuronal apoptosis in the hippocampus.Apoptosis-related protein B-cell lymphoma-2(Bcl-2),BCL2associated X protein(Bcl-2 Assaciated X,Bax)and nuclear factor kappaB(NFκB)expression.Results:The learning and memory ability of the young mice in the model group was significantly reduced,the brain infarct volume was significantly increased,the expressions of BDNF and TrkB proteins in the hippocampus were significantly increased,and the expression of CREB proteins was significantly decreased;After overexpression of BDNF and TrkB CREB,in the LVBDNF,LVTrkB,and LVCREB group,the learning and memory ability of young mice were significantly improved,the brain infarct volume were significantly reduced,the hippocampal neuronal apoptosis were significantly reduced,The protein expression of Bax and NFκB were significantly decreased and the protein expression of Bcl2 were significantly enhanced.Conclusion:The expression of BDNF/TrkB/CREB is abnormal in HIBI model young mice.Overexpression of BDNF/TrkB/CREB can improve the learning and memory ability of young mice,repair brain tissue damage,and inhibit neuronal apoptosis.Therefore,the mechanism of HIBI may be related to BDNF/TrkB/CREB pathways.展开更多
Objective:To explore the mechanism of acupuncture intervention on anti-neuronal apoptosis in heroindependent rats based on the PI3K/AKT signaling pathway.Methods:A total of 30 SD rats were randomly divided into a norm...Objective:To explore the mechanism of acupuncture intervention on anti-neuronal apoptosis in heroindependent rats based on the PI3K/AKT signaling pathway.Methods:A total of 30 SD rats were randomly divided into a normal group,a model group and an acupuncture group,10 rats in each one.In the model group and the acupuncture group,the heroin relapse rat model was established by intramuscular incremental injection of heroin.In the model group,no any intervention was applied.In the acupuncture group,after modeling,acupuncture was applied at"Bǎihuì(百会GV20)"and"Dàzhuī(大椎GV14)".Transmission electron microscope(TEM)was adopted to observe neuronal apoptosis in the rats.The effect of acupuncture on anti-neuronal apoptosis was compared.Using reverse transcription-polymerase chain reaction(RT-PCR)and western blot methods,the mRNA and protein expressions of PI3 K and AKT were detected in ventral tegmental area(VTA).Results:It was found that edema was presented in VTA neuronal cytoplasm and organelles basically disappeared in the heroin relapse rats,nuclear chromatin aggregation,condensation and increased neuronal apoptosis were presented as well.After acupuncture at"Bǎihuì(百会GV20)"and"Dàzhuī(大椎GV14)",a small amount of mitochondria,rough endoiplasmic reticulum and glycogen granules were visible in the cytoplasm of VTA neurons.The nuclear membrane structure was clear and the chromatin in the nucleus was basically normal.The fluorescence quantitative polymerase chain reaction(PCR)and western blot methods were adopted to detect mRNA and protein expressions of PI3K and AKT.It was found that the mRNA and protein expressions of PI3K and AKT in the brain of the rats in the model group were lower than those in the normal group(all P<0.05).Compared with the model group,the mRNA and protein expressions of PI3K and AKT in the acupuncture group were increased(all P<0.05),tending to the levels as the normal group.Conclusion:The effect of acupuncture on anti-brain cell apoptosis in heroin relapse rats may be related to the inhibition of PI3K/AKT signaling pathway.展开更多
γ-amidobutyric acid (GABA) is a major inhibitory neurotransmitter in the central nervous system and mediates fast synaptic inhibition through GABAA and GABAC
BACKGROUND： Aggregation of α-synuclein is the major component of Lewy bodies, which are the pathological hallmarks of Parkinson disease （PD）. Although the mechanism of this protein aggregates is unclear, previous ...BACKGROUND： Aggregation of α-synuclein is the major component of Lewy bodies, which are the pathological hallmarks of Parkinson disease （PD）. Although the mechanism of this protein aggregates is unclear, previous study showed that environmental toxins such as rotenone could induce the expression and aggregation of α-synuclein. OBJECTIVE： To observe the role of α-synuclein in PD.DESIGN ： A randomized controlled trial.SETTING ： Beijing Institute for Neuroscience, Capital University of Medical Sciences.MATERIALS ： This study was performed from July 2005 to January 2006 at the Beijing Institute for Neuroscience, Capital University of Medical Sciences. Human dopaminergic neuroblastoma SH-SY5Y cells were provided by Beijing Institute for Neuroscience, Capital University of Medical Sciences. METHODS： Human dopaminergic neuroblastoma SH-SY5Y cells were treated to make α-synuclein over express. Rotenone was added into the medium of cultured both native SH-SY5Y cells and α-synuclein-overexpression SH-SY5Y cells. Lactate dehydrogenase （LDH） assay was used to detect with the cell viability. Flow cytometry and electrophoresis were adopted to measure the cell apoptosis. MAIN OUTCOME MEASURES ： Cell viability, DNA fragmentation, and the number of cell apoptosis.RESULTS： After being treated with rotenone, LDH activity of α-synuclein overexpressed SH-SY5Y cells was （76.625±6.34） μkat/L, which was significantly lower than that of control group （P 〈 0.05）. As compared with normal SH-SY5Y cell, α-synuclein over-expressed SH-SY5Y cells had less DNA fragments and apoptotic cells, α-synuclein might play a role in cell apoptosis induced by rotenone, which was also confirmed by using of antioxidant reagent. CONCLUSION： α-synuclein may partially protect against cell apoptosis induced by rotenone in SH-SY5Y cells.展开更多
BACKGROUND： Aquaporin-4 （AQP-4） is closely related to the formation of brain edema. Neuronal apoptosis plays an important part in the conversion of swelled neuron following traumatic brain injury. At present, the s...BACKGROUND： Aquaporin-4 （AQP-4） is closely related to the formation of brain edema. Neuronal apoptosis plays an important part in the conversion of swelled neuron following traumatic brain injury. At present, the studies on the protective effect of ketamine on brain have involved in its effect on aquaporin-4 expression and neuronal apoptosis in the brain tissues following brain injury in rats. OBJECTIVE： To observe the effect of ketamine on AQP-4 expression and neuronal apoptosis in the brain tissue following rat brain injury, and analyze the time-dependence of ketamine in the treatment of brain injury.DESIGN： Randomized grouping design, controlled animal tria SETTING ： Department of Anesthesiology, the Medical School Hospital of Qingdao University MATERIALS： Totally 150 rats of clean grade, aged 3 months, were involved and randomized into control group and ketamine-treated group, with 75 rats in each. Each group was divided into 5 subgroups separately at 6,12, 24, 48 and 72 hours after injury, with 15 rats at each time point. Main instruments and reagents： homemade beat machine, ketamine hydrochloride （Hengrui Pharmaceutical Factory, Jiangsu）, rabbit anti-rat AQP-4 polyclonal antibody, SABC immunohistochemical reagent kit and TUNEL reagent kit （Boster Co.,Ltd., Wuhan）. METHODS： This trial was carried out in the Institute of Cerebrovascular Disease, Medical College of Qingdao University during March 2005 to February 2006. A weight-dropping rat model of brain injury was created with Feeney method. The rats in the ketamine-treated group were intraperitoneally administered with 50 g/L ketamine （120 mg/kg） one hour after injury, but ketamine was replaced by normal saline in the control group. In each subgroup, the water content of cerebral hemisphere was measured in 5 rats chosen randomly. The left 10 rats in each subgroup were transcardiacally perfused with ketamine, then the brain tissue was made into paraffin sections and stained by haematoxylin and eosin. Neuronal morphology was observed. AQP-4 expression and neuronal apoptosis were measured with immunohistochemical method and TUNEL method respectively. MAIN OUTCOME MEASURES： Water content in brain tissue, neuronal morphology, the number of AQP-4 positive neurons and TUNEL positive neurons in rats of two groups at each time point after injury. RESULTS： Totally 150 rats entered the stage of result analysis. （1） Water content of brain tissue： The water content of brain tissue at each time point after injury in the ketamine-treated group was lower than that in the control group. There were very significant differences in water content at 12 and 24 hours after injury respectively between ketamine-treated group and control group [（77.34±2.35）% vs. （82.31 ±1.48）%; （78.01 ±2.21 ）% vs. （83.86±2.37）%, t=-4.001 6,4.036 7, both P 〈 0.01]. （2） Neuronal morphology： Pathological changes in traumatic region and peripheral region of injury in the ketamine-treated group were significantly lessened, and necrotic and apoptotic cells in the ketamine-treated group were also significantly reduced as compared with control group. （3） AQP-4 expression： AQP-4 positive neurons at each time point in the ketamine-treated group were significantly less than those in the control group. There were very significant differences in AQP-4 expression at 12 and 24 hours after injury between ketamine-treated group and control group [（34.17±4.74） /visual field vs. （43.42±5.65） /visual field;（40.83±3.17） /visual field vs. （58.88±6.23） /visual field,t=3.966 3,8.165 7, both P〈 0.01]. （4） Neuronal apoptosis： TUNEL positive neurons at each time point in the ketamine-treated group were less than those in the control group. There were very significant differences in the neuronal apoptosis at 12 and 24 hours after injury between ketamine-treated group and control group [（26.25±3.04） /visual field vs. （32.75±4.39） /visual field; （29.33± 4.02） /visual field vs. （39.83±5.61） /visual field,t=-3.849 3,5.169 2,both P 〈 0.01]. CONCLUSION： Ketamine can reduce brain edema, AQP-4 expression and neuronal apoptosis following brain injury in rats, and has obvious therapeutic effect on brain injury, especially at 12 and 24 hours after injury.展开更多
BACKGROUND： It is proved that the onset of Parkinson disease companies with neuronal apoptosis of dopamine in substantia nigra of midbrain. Previous researches on neuronal apoptosis of dopamine were analyzed on their...BACKGROUND： It is proved that the onset of Parkinson disease companies with neuronal apoptosis of dopamine in substantia nigra of midbrain. Previous researches on neuronal apoptosis of dopamine were analyzed on their consecutive tissue sections with immunohistochemical single-labeling method, immunofluorescence and electron microscope, and there are significant differences.OBJECTIVE ： To observe the feasibility of neuronal apoptosis of dopamine with in situ end labeling and tyrosine-hydroxylase antibody immunohistochemical double-labeling staining technique.DESIGN ： Controlled study.SETTING： College of Pharmacology of Taishan Medical College; College of Management of Taishan Medical College. MATERIALS ： Wistar rats with 2 weeks old and of clean grade were provided by the Animal Center of Taishan Medical College. In situ end labeling kit （terminal deoxynucleotidyl transferase, mixed reactive solution of nucleotide, transfusion-POD）, monoclonal antibody of rat antibody against tyrosine hydroxylase （Boehriuser）. METHODS： The experiment was completed at the Pharmacological Laboratory of Taishan Medical College from February to December 2005. Tissue from midbrain of rats was taken out to make paraffin sections to observe the neuronal apoptosis of dopamine under microscope with in situ end labeling and tyrosine-hydroxylase antibody immunohistochemical double-labeling staining technique.MAIN OUTCOME MEASURES ： Neuronal apoptosis of dopamine with in situ end labeling and tyrosine-hydroxylase antibody immunohistochemical double-labeling staining technique. RESULTS： ① After double-labeling staining, two kinks of positive products were observed in neurons of dopamine which were suffered from apoptosis. One stained with tyrosine hydroxylase was hyacinthine, and the other stained with in situ end labeling was buffy. Cells of positive products stained with in situ end labeling shaped as strap and bend and was distributed in clustering. Cytoplasm was hyacinthine, staining was symmetrical, and cellular ecphyma was observed. Nucleus was stained vacantly which was coincidence with form of neurons of dopamine. ②Apoptosis showed strictly in cytoplasm and nucleus at the aspect of morphology. Cytoplasm stained with in situ end labeling was hardly to recognize because of the usage of double-labeling staining technique, but nucleus was still characterized by apoptosis. The behavior of positive products stained with in situ end labeling was described as following： nucleus was buffy; karyopycnosis was round and irregular; caryotin was integrated into clump which was distributed at the border of nucleus and shaped as demilune and anular; positive signals were limited in nucleus and coincidence with morphological changes of apoptosis. However, blue and positive products were observed in cytoplasm of neurons of dopamine which did not occur apoptosis, and the nucleus was not labeled. Therefore, processing apoptosis of neurons of dopamine could be recognized. CONCULSION： Double-labeling staining technique can be used to correctly reveal histological and morphological changes of neuronal apoptosis of dopamine during its onset and development.展开更多
BACKGROUND: It has been demonstrated that adenosine can induce glial cell to release cytochrome C, enhance expression of apoptotic gene bax, inhibit anti-apoptotic gene bcl-2, and activate caspase-3 to apoptosis; Wher...BACKGROUND: It has been demonstrated that adenosine can induce glial cell to release cytochrome C, enhance expression of apoptotic gene bax, inhibit anti-apoptotic gene bcl-2, and activate caspase-3 to apoptosis; Whereas inosine can inhibit neuronal apoptosis which is similar to bcl-2. OBJECTIVE: To observe the effects of inosine on neuronal apoptosis and expression of cytochrome C mRNA in rats after focal cerebral ischemia/reperfusion, and analyze the pathway of its neuroprotective effect. DESIGN: A randomised controlled animal trial. SETTINGS: Department of Neurology, Rongcheng Second People's Hospital; Department of Neurology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. MATERIALS: Sixty-eight rats, weighing 230-280 g and clean grade, were used. TdT-mediated dUTP-biotin nick end labeling (TUNEL) and cytochrome C mRNA in situ hybridization kits and DAB staining kit were purchased from Wuhan Boster Biological Co., Ltd.; Inosine injection [200 mg (2 mL) each] from Qingdao First Pharmaceutical Factory. METHODS: The experiment was accomplished in the animal experimental center in Tongji Medical College of Huazhong University of Science and Technology from December 2003 to June 2005. ① Sixty-four rats were made into focal ischemia by middle cerebral artery occlusion (MCAO) with a nylon monofilament suture. The successfully induced rats were assigned to inosine group (n =32) and model group (n =32) at random. Rats in the inosine group were intraperitoneally administrated with inosine in dose of 100 mg/kg preoperatively, twice a day, 7 days in all. The rats in the control group were injected with the same dose of saline solution by the similar way preoperatively. Each group was randomized into ischemia /reperfusion 2, 6, 12, 24 hours, 2, 3, 7 and 14 days subgroups consisted of 4 rats. The other 4 rats were taken as the sham-operated group, the rats were given the same treatment except for not introduced the filament into the external carotid artery stump, and brain tissue was removed at 2 hours of reperfusion. ② In situ hybridization was performed to examine the expression of cytochrome C mRNA while TUNEL staining was made to characterize apoptosis. ③ The t test was used to compare the difference of measurement data. MAIN OUTCOME MEASURES: ① Neuronal apoptosis in the different regions of the ischemic brain tissue; ② Expression of cytochrome C mRNA in the different regions at different time points after MCAO. RESULTS: All the 68 rats were involved in the analysis of results. ① Neuronal apoptosis: A small number of TUNEL-positive cells were detected in the sham-operated brain and non-ischemic brain. The number of apoptotic cells in the ischemic cortex peaked at 24 hours of reperfusion [(72.00±1.98) cells] and that in the striatum peaked at 2 days [(94.75±3.57) cells], then decreased to the level of sham-operated group at 14 days. Inosine could reduce apoptotic cells from 12 hours to 7 days of reperfusion as compared with the model group (t =6.19-26.67, P < 0.01). ② Cytochrome C mRNA expression: There was weak expression of cytochrome C mRNA in both sham-operated brain and contralateral brain. Cytochrome C was detected at 2 hours of reperfusion in ischemic brain [(25.75±3.50), (39.75±2.49) cells], and strongly increased to a peak at 12 hours and 24 hours of reperfusion in cortex and striatum [(122.50±6.69), (119.25±5.12) cells], respectively. Furthermore, inosine could significantly decrease cytochrome C expression in cortex at 12 hours to 14 days of reperfusion after ischemic reperfusion and that in striatum at 12 hours to 3 days (t =8.67-43.26, P < 0.01). CONCLUSION: Inosine can exert a neuroprotective effect by inhibiting apoptosis and cytochrome C mRNA expression.展开更多
文摘The purpose of this study was to evaluate the roles of different housing environments in neurological function, cerebral metabolism, cerebral infarction and neuron apoptosis after focal cerebral ischemia. Twenty-eight Sprague-Dawley rats were divided into control group （CG） and cerebral ischemia group, and the latter was further divided into subgroups of different housing conditions： standard environment （SE） subgroup, individual living environment （IE） subgroup, and enriched environment （EE） subgroup. Focal cerebral ischemia was induced by the middle cerebral artery occlusion （MCAO）. Beam walking test was used to quantify the changes of overall motor function. Cerebral infarction and cerebral metabolism were studied by in vivo magnetic resonance imaging and 1H-magnetic resonance spectra, respectively. Neuron necrosis and apoptosis were detected by hematoxylin-eosin and TUNEL staining methods, respectively. The results showed that performance on the beam-walk test was improved in EE subgroup when compared to SE subgroup and IE subgroup. Cerebral infarct volume in IE subgroup was significantly larger than that in SE subgroup （P〈0.05） and EE subgroup （P〈0.05） on day 14 after MCAO. NAA/Cr and Cho/Cr ratios were lower in MCAO groups under different housing conditions as compared to those in CG （P〈0.05）. NAA/Cr ratio was lower in IE subgroup （P〈0.05） and higher in EE subgroup （P〈0.05） than that in SE subgroup. NAA/ Cr ratio in EE was significantly higher than that in IE subgroup （P〈0.05）. Cho/Cr ratio was decreased in MCAO groups as compared to that in CG （P〈0.05）. A significant decrease in normal neurons in cerebral cortex was observed in MCAO groups as compared to CG （P〈0.05）. The amount of normal neurons was less in IE subgroup （P〈0.05）, and more in EE subgroup （P〈0.05） than that in SE subgroup after MCAO. The amotmt of normal neurons in EE subgroup was significantly more than that in IE subgroup after MCAO （P〈0.05）. The ratio of TUNEL-positive neurons in EE was significantly lower than that in SE subgroup （P〈0.05） and IE subgroup （P〈0.05）. Correlation analysis showed that the beam walking test was negatively correlated with NAA/Cr ratio （P〈0.05）. Cerebral infarct volume was negatively correlated with both NAA/Cr ratio （P〈0.01） and Cho/Cr ratio （P〈0.01）. The amount of normal cortical neurons was positively correlated with both NAA/Cr ratio （P〈0.0I） and Cho/Cr ratio （P〈0.05）. The TUNEL-positive neurons showed a negative correlation with both NAA/Cr ratio （P〈0.01） and Cho/Cr ratio （P〈0.01）. This study goes further to show that EE may improve neurological functional deficit and cerebral metabolism, decrease cerebral infarct volume, neuron necrosis and apoptosis, while IE may aggravate brain damage after MCAO.
基金Supported by the Major Research Plan from the Health Commission of Hongkou District,No.2001-03Academic Subject Boosting Plan in the Shanghai Fourth People’s Hospital affiliated to Tongji University School of Medicine Shanghai,No.SY-XKZT-2020-1003.
文摘BACKGROUND Spinal cord injury(SCI)is a severe and permanent trauma that often leads to significant motor,sensory,and autonomic dysfunction.Neuronal apoptosis is a major pathomechanism underlying secondary injury in SCI.Long non-coding RNAs(lncRNAs)have emerged as key regulators of gene expression and cellular processes,including apoptosis.However,the role of lncRNA growth arrest-specific transcript 5(GAS5)in SCI-induced neuronal apoptosis remains unclear.AIM To investigate the role of lncRNA GAS5 in SCI-induced neuronal apoptosis via its interaction with microRNA(miR)-21 and the phosphatase and tensin homolog(PTEN)/AKT pathway.METHODS SCI rat models and hypoxic neuronal cell models were established.Motor function was assessed using the Basso-Beattie-Bresnahan score.Expression levels of GAS5,miR-21,PTEN,caspase 3,B-cell lymphoma 2(Bcl-2),Bcl-2-associated X protein(Bax),and AKT were measured using quantitative PCR or Western blot analysis.Neuronal apoptosis was determined by TUNEL staining.Dual-luciferase reporter assays validated GAS5-miR-21 binding.Knockdown and overexpression experiments explored the functional effects of the GAS5/miR-21 axis.RESULTS GAS5 was significantly upregulated in the spinal cord following SCI,coinciding with increased neuronal apoptosis and decreased AKT activation.In vitro experiments demonstrated that GAS5 acted as a molecular sponge for miR-21,leading to increased PTEN expression and inhibition of the AKT signaling pathway,thereby promoting apoptosis.In vivo,GAS5 knockdown attenuated neuronal apoptosis,enhanced AKT activation,and improved motor function recovery in SCI rats.CONCLUSION GAS5 promotes neuronal apoptosis in SCI by binding to miR-21 and upregulating PTEN expression,inhibiting the AKT pathway.Targeting GAS5 may represent a novel therapeutic strategy for SCI.
基金funding from the European Union -NextGenerationEU through the Italian Ministry of University and Research under PRIN PNRR REG D.R.1718-2022– Project number PRJ-1575 INDICA。
文摘Indicaxanthin is a betalain that is abundant in Opuntia ficus-indica orange fruit and has antioxidative and anti-inflammatory effects. Nevertheless, very little is known about the neuroprotective potential of indicaxanthin. This study investigated the impact of indicaxanthin on neuronal damage and gut microbiota dysbiosis induced by a high-fat diet in mice. The mice were divided into three groups according to different diets: the negative control group was fed a standard diet;the high-fat diet group was fed a high-fat diet;and the high-fat diet + indicaxanthin group was fed a high-fat diet and received indicaxanthin orally(0.86 mg/kg per day) for 4 weeks. Brain apoptosis, redox status, inflammation, and the gut microbiota composition were compared among the different animal groups. The results demonstrated that indicaxanthin treatment reduced neuronal apoptosis by downregulating the expression of proapoptotic genes and increasing the expression of antiapoptotic genes. Indicaxanthin also markedly decreased the expression of neuroinflammatory proteins and genes and inhibited high-fat diet–induced neuronal oxidative stress by reducing reactive oxygen and nitrogen species, malondialdehyde, and nitric oxide levels. In addition, indicaxanthin treatment improved the microflora composition by increasing the abundance of healthy bacterial genera, known as producers of short-chain fatty acids(Lachnospiraceae, Alloprovetella, and Lactobacillus), and by reducing bacteria related to unhealthy profiles(Blautia, Faecalibaculum, Romboutsia and Bilophila). In conclusion, indicaxanthin has a positive effect on high-fat diet–induced neuronal damage and on the gut microbiota composition in obese mice.
基金Health Commission of Hubei Province(No.ZY2021M014)the National Natural Science Foundation of China(No.81873725)+2 种基金Basic Scientific Research Funds of Department of Education of Zhejiang Province(No.KYYB202007)Zhejiang Basic Public Welfare Research Program(No.LGF22H280016)the“13th Five-Year”Chinese Medicine Key Discipline in Zhejiang Province-Chinese Medicine Quality and Functional Evaluation(No.2017-XK-A43).
文摘Objective Cerebral ischemia/reperfusion(I/R)is a potential factor for lethal injury,and currently lacks effective remedies.Bauhinia championii extracts(BCEs)have been reported to exhibit anti-oxidative and anti-hypoxia properties.The current work aimed to study whether BCE could alleviate neuronal injury caused by I/R.Methods To investigate the protective effects of BCE,oxygen-glucose deprivation/reperfusion(OGD/R)was applied to the HT22 cell line in vitro and to a cerebral I/R mouse model in vivo.Results Under OGD/R,the survival of HT22 cells was significantly prolonged after treatment with BCE.In vivo,BCE significantly reduced the infarct area and decreased neuronal apoptosis caused by I/R.It was further found that OGD/R could trigger endoplasmic reticulum(ER)stress and induce ER stress-mediated neuronal apoptosis in vivo and in vitro,while BCE could effectively alleviate ER stress and neuronal apoptosis.Conclusion These results suggested that BCE exhibits neuroprotective effects by reducing ER stress-mediated apoptosis after cerebral I/R injury.BCE may therefore be an effective therapeutic regimen against cerebral I/R damage.
基金supported by the National Natural Science Foundation of China,Nos.81971870,82172173(both to MCL)。
文摘Subarachnoid hemorrhage(SAH)is a dominant cause of death and disability wo rldwide.A sharp increase in intracranial pressure after SAH leads to a reduction in cerebral perfusion and insufficient blood supply for neuro ns,which subsequently promotes a series of pathophysiological responses leading to neuronal death.Many previous experimental studies have reported that excitotoxicity,mitochondrial death pathways,the release of free radicals,protein misfolding,apoptosis,nec rosis,autophagy,and inflammation are involved solely or in combination in this disorder.Among them,irreversible neuronal apoptosis plays a key role in both short-and long-term prognoses after SAH.Neuronal apoptosis occurs through multiple pathways including extrinsic,mitochondrial,endoplasmic reticulum,p53 and oxidative stress.Meanwhile,a large number of blood contents enter the subarachnoid space after SAH,and the secondary metabolites,including oxygenated hemoglo bin and heme,further aggravate the destruction of the blood-brain barrier and vasogenic and cytotoxic brain edema,causing early brain injury and delayed cerebral ischemia,and ultimately increasing neuronal apoptosis.Even there is no clear and effective therapeutic strategy for SAH thus far,but by understanding apoptosis,we might excavate new ideas and approaches,as targeting the upstream and downstream molecules of apoptosis-related pathways shows promise in the treatment of SAH.In this review,we summarize the existing evidence on molecules and related drugs or molecules involved in the apoptotic pathway after SAH,which provides a possible target or new strategy for the treatment of SAH.
基金supported by the National Natural Science Foundation of China,Nos.81974189(to HLT),81801236(to QYG and LC),82001310(to DXY).
文摘Urolithin A(UA)is a natural metabolite produced from polyphenolics in foods such as pomegranates,berries,and nuts.UA is neuroprotective against Parkinson’s disease,Alzheimer’s disease,and cerebral hemorrhage.However,its effect against traumatic brain injury remains unknown.In this study,we established adult C57BL/6J mouse models of traumatic brain injury by controlled cortical impact and then intraperitoneally administered UA.We found that UA greatly reduced brain edema;increased the expression of tight junction proteins in injured cortex;increased the immunopositivity of two neuronal autophagy markers,microtubule-associated protein 1A/B light chain 3A/B(LC3)and p62;downregulated protein kinase B(Akt)and mammalian target of rapamycin(mTOR),two regulators of the phosphatidylinositol 3-kinase(PI3K)/Akt/mTOR signaling pathway;decreased the phosphorylation levels of inhibitor of NFκB(IκB)kinase alpha(IKKα)and nuclear factor kappa B(NFκB),two regulators of the neuroinflammation-related Akt/IKK/NFκB signaling pathway;reduced blood-brain barrier permeability and neuronal apoptosis in injured cortex;and improved mouse neurological function.These findings suggest that UA may be a candidate drug for the treatment of traumatic brain injury,and its neuroprotective effects may be mediated by inhibition of the PI3K/Akt/mTOR and Akt/IKK/NFκB signaling pathways,thus reducing neuroinflammation and enhancing autophagy.
基金This work was supported by the National Natural Science Foundation of China(81771961 and 81401505)the Kuanren Talents Program of the Second Affiliated Hospital of Chongqing Medical University(201959).
文摘Neuronal apoptosis is one of the essential mechanisms of early brain injury after subarachnoid hemorrhage(SAH).Recently,HLY78 has been shown to inhibit apoptosis in tumor cells and embryonic cells c aused by carbon ion radiation through activation of the Wnt/β-catenin pathway.This study was designed to explore the anti-apoptotic role of HLY78 in experimental SAH.The results demonstrated that HLY78 attenuated neuronal apoptosis and the neurological deficits after SAH through the activation of low-density lipoprotein receptor-related protein 6(LRP6),which subsequently increased the level of phosphorylated glycogen synthesis kinase 3 beta(p-GSK3β)(Ser9),β-catenin,and Bcl-2,accompanied by a decrease of p-β-catenin,Bax,and cleaved caspase 3.An LRP6 small-interfering ribonucleic acid reversed the effects of HLY78.In conclusion,HLY78 attenuates neuronal apoptosis and improves neurological deficits through the LRP6/GSK3β/β-catenin signaling pathway after SAH in rats.HLY78 is a promising therapeutic agent to attenuate early brain injury after SAH.
基金supported by the National Natural Science Foundation of China, No. 81160157projects of Science and Technology Bureau of Guizhou Province, No.20093075, 20072127
文摘Apoptosis in cultured rat hippocampal neurons was induced using the nitric oxide donor 3-morpholinosydnonimine, and cells were treated with the chloride channel blocker, 4,4- diisothiocyanatostilbene-2,2＇-disulfonic acid. Results showed that the survival rate of neurons was significantly increased after treatment with 4,4-diisothiocyanatostilbene-2,2＇-disulfonic acid, and the rate of apoptosis decreased. In addition, the expression of the apoptosis-related proteins poly（adenosine diphosphate-ribose）polymerase-1 and apoptosis-inducing factor were significantly reduced. Our experimental findings indicate that the chloride channel blocker 4,4- diisothiocyanatostilbene-2,2＇-disulfonic acid can antagonize apoptotic cell death of hippocampal neurons by inhibiting the expression of the apoptosis-related proteins poly（adenosine diphosphate-ribose）polymerase-1 and apoptosis-inducing factor.
基金supported by the National Science Foundation of China(Nos.91543203,21377076)the Specialized Research Fund for the Doctoral Program of Higher Education(Nos.20121401110003,20131401110005)the Research Project Supported by Shanxi Scholarship Council of China(No.2015-006)
文摘Epidemiological studies have shown that particulate matter 2.5（PM（2.5）） not only increases the incidence of cardiopulmonary illnesses but also relates to the development of neurodegenerative diseases. Considering that PM（2.5）is highly heterogeneous with regional disparity and seasonal variation, we investigated whether PM（2.5）exposure induced neuronal apoptosis and synaptic injuries in a season-dependent manner. The results indicated that PM（2.5）altered the expression of apoptosis-related proteins（mainly bax and bcl-2）, activated caspase-3 and caused neuronal apoptosis. Additionally, PM（2.5）decreased the levels of synaptic structural protein postsynaptic density（PSD-95） and synaptic functional protein N-methyl-D-aspartate（NMDA） receptor subunit（NR2B） expression. These effects occurred in a season-dependent manner, and PM（2.5）collected from the winter showed the strongest changes. Furthermore, the effect was coupled with the inhibition of phosphorylated extracellular signal-regulated kinase 1/2（p-ERK1/2） and phosphorylated c AMP-response element binding protein（p-CREB）. Based on the findings, we analyzed the correlations between the chemical composition of PM（2.5）samples and the biological effects, and confirmed that winter PM（2.5）played a major role in causing neuronal apoptosis and synaptic injuries among different season samples.
文摘BACKGROUND： Apoptosis plays an important role in central neural diseases and trauma. B-cell lymphoma/Leukemia-2 （Bcl-2） can inhibit apoptosis in a wide variety of cells including neurons. In this experiment, by studying Bcl-2 over-expression transgenic （TG） mice subjected to spinal cord injury （SCI）, we investigated whether Bcl-2 could reduce posttraumatic neuronal apoptosis, reduce the range of damage, and improve the behavioral functional recovery after contusive SCI.METHODS： Nine Bcl-2 TG mice and nine control mice were subjected to SCI of moderate severity at T10, with the use of weight dropping （WD） method （impact force 2.5×3.0 g/cm）. At times up to 1 day, 7 days and 14 days after SCI, functional defi cits were evaluated with Basso, Beattie, and Bresnahan （BBB） scales, and apoptosis of neurons was investigated by using the TUNEL method. Another three control mice only underwent lamina opening, but were not subjected to SCI, to provide blank comparison.RESULTS： The mean functional scores for the control mice （5.05 ±0.35） were lower than those for the Bcl-2 TG mice （5.45 ±0.15）, although the unpaired T-test revealed no signifi cant difference （P=0.67）. On the other hand, the number of TUNEL positive neurons and integrated option density （IOD） scores for the Bcl-2 TG mice were both signifi cantly lower than those for the control mice （P〈0.05）.CONCLUSIONS： This experiment suggests that overexpression of Bcl-2 may suppress neuronal apoptosis after SCI. Bcl-2 may be an important factor within the central nervous system that can relieve the damage after trauma.
文摘Programmed cell death （PCD） signaling pathways are import- ant contributors to acute neurological insults such as hypox- ic-ischemic brain damage, traumatic brain injury, stroke etc. The pathogenesis of all these diseases is closely linked with ab- erration of apoptotic cell death pathways. Mitochondria play a crucial role during PCD, acting as both sensors of death signals, and as initiators of biochemical path- ways, which cause cell death （Bras et al., 2005）. Cytochrome c was the firstly identified apoptogenic factor released from mitochondria into the cytosol, where it induces apoptosome formation through the activation of caspases. Other proteins, such as apoptosis inducing factor （AIF）, have been subsequently identified as mitochondrial released factors. AIF contributes to apoptotic nuclear DNA damage （Bras et al., 2005）. in a caspase-independent way
文摘Ischemic stroke is most commonly caused by vascular occlusion due to thrombosis or arterial embolism. Recently, thrombolysis has been used with increasing frequency for the treatment of acute ischemic stroke. Among the drugs used for thrombolysis, only recombinant tissue plasminogen activator is widely accepted internationally （Albers et al., 2008）. In China, urokinase has been widely used for thrombolysis after acute ischemic stroke. Pro-uro- kinase is the precursor of urokinase. Compared with urokinase, pro-uroki- nase has greater ability to dissolve thrombus and is safer to use.
文摘BACKGROUND： The neuroprotective effects of （-）-epigallocatechin-3-gallate （EGCG）, the main polyphenolic constituent of green tea, have been widely reported. However, the action mechanisms, in particular in D-galactose-induced aging mice, remain poorly understood. OBJECTIVE： The present study investigated the protective effects of EGCG on D-galactose-induced hippocampus neuronal apoptosis in aging mice, as well as the relationship with expression of p751CD, JNK2, and p53 proteins. DESIGN, TIME AND SETTING： A randomized, controlled, molecular biological, animal experiment was performed at the Laboratory of Pharmacology, Pharmaceutical College of China Medical University, China, from September 2006 to July 2008. MATERIALS： D-galactose and EGCG （Sigma, USA）, as well as terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling （TUNEL） In Situ Cell Apoptosis Detection Kit （Promega, USA）, were used in this study. METHODS： A total of 64 mice were equally and randomly divided into D-galactose model, low-dose EGCG, high-dose EGCG, and control groups. Mice in the D-galactose model, low-dose EGCG, and high-dose EGCG groups were subcutaneously injected with 3% D-galactose （150 mg/kg）, daily for 6 weeks, to establish a mouse model of aging. Mice in the control group were treated with saline （5 mL/kg）. At 3 weeks following injection, mice in the low-dose EGCG and high-dose EGCG groups were orally administered EGCG at a dose of 2 mg/kg and 6 mg/kg, respectively, once a day, for 4 consecutive days. Mice in the control and D-galactose model groups received distilled water （5 mL/kg）. MAIN OUTCOME MEASURES： Memory function was evaluated using a step-through passive avoidance test. Neuronal apoptosis in the mouse hippocampus was detected using TUNEL staining. Expression levels of the intracellular domain of the p75 neurotrophin receptor （p75NTR）-p751CD, JNK2, and p53 proteins in the hippocampus were determined using Western blot analysis. RESULTS： The aging mouse model was induced by subcutaneous injection of D-galactose, which resulted in obvious memory impairment, increased apoptotic index, and increased protein expression levels of p751CD, JNK2, and p53 in the hippocampus, compared with control mice （P 〈 0.01）. Oral EGCG administration （2 or 6 mg/kg） for 4 weeks significantly improved levels of memory deficit in the aging mice and reduced apoptotic indices and protein expression levels of p751CD, JNK2, and p53 in the mouse hippocampus （P 〈 0.01）. CONCLUSION： Results from this study demonstrated increased protein expression levels of p751CD, JNK2, and p53, as well as increased hippocampal neuronal apoptosis in a D-galactose-induced mouse model of aging. EGCG provided protective effects against D-galactose-induced neuronal apoptosis in the hippocampus by reducing protein expression levels of p751CD, JNK2, and p53 proteins in the hippocampus of aging mice.
基金Hainan Provincial Natural Science Foundation of China(NO.819QN388)。
文摘Objective:Based on the BDNF/TrkB/CREB pathway,to explore the mechanism of neuronal apoptosis and brain developmental injury in the hippocampus of hypoxic-ischemic neonatal rats.Methods:Wistar young rats were ligated on one side of the common carotid artery and placed in an 8%oxygen and 92%nitrogen hypoxia box for 2 h to prepare hypoxic-ischemic brain injury models.Healthy rats were used as the control group.Control group and model group were selected,with 10 rats in each group,and the learning and memory ability was tested by Y-maze;2,3,5-triphenyltetrazolium chloride(TTC)staining was used to detect brain tissue damage;Western blot was performed to determine the expression of brain-derived neurotrophic factor(BDNF),tyrosine protein kinase B(TrKB)and cAMP-response element binding protein(CREB)in hippocampal tissue.Another 15 mice in the control group and 60 mice in the model group were divided into negative control group(NC),BDNF overexpression group(LV-BDNF),TrkB overexpression group(LV-TrkB),and CREB overexpression group(LV-CREB),blank vector,BDNF,TrkB,CREB adenovirus overexpression vector was injected into the tail vein.Y-maze test for learning and memory ability;TTC staining method to detect brain tissue damage;neuronal apoptosis in the hippocampus were detected by terminal-deoxynucleoitidyl transferase mediated nick end labeling;Western blot to detect the level of neuronal apoptosis in the hippocampus.Apoptosis-related protein B-cell lymphoma-2(Bcl-2),BCL2associated X protein(Bcl-2 Assaciated X,Bax)and nuclear factor kappaB(NFκB)expression.Results:The learning and memory ability of the young mice in the model group was significantly reduced,the brain infarct volume was significantly increased,the expressions of BDNF and TrkB proteins in the hippocampus were significantly increased,and the expression of CREB proteins was significantly decreased;After overexpression of BDNF and TrkB CREB,in the LVBDNF,LVTrkB,and LVCREB group,the learning and memory ability of young mice were significantly improved,the brain infarct volume were significantly reduced,the hippocampal neuronal apoptosis were significantly reduced,The protein expression of Bax and NFκB were significantly decreased and the protein expression of Bcl2 were significantly enhanced.Conclusion:The expression of BDNF/TrkB/CREB is abnormal in HIBI model young mice.Overexpression of BDNF/TrkB/CREB can improve the learning and memory ability of young mice,repair brain tissue damage,and inhibit neuronal apoptosis.Therefore,the mechanism of HIBI may be related to BDNF/TrkB/CREB pathways.
基金Supported by Youth Fund Project of National Natural Science Foundation of China: 81503658Key Project of Natural Science Research in Universities of Anhui Province: KJ2017A289+1 种基金Anhui University Scientific Research Platform Construction Project: 2015TD033Exploration Project of Anhui University of Traditional Chinese Medicine: 2016ts078
文摘Objective:To explore the mechanism of acupuncture intervention on anti-neuronal apoptosis in heroindependent rats based on the PI3K/AKT signaling pathway.Methods:A total of 30 SD rats were randomly divided into a normal group,a model group and an acupuncture group,10 rats in each one.In the model group and the acupuncture group,the heroin relapse rat model was established by intramuscular incremental injection of heroin.In the model group,no any intervention was applied.In the acupuncture group,after modeling,acupuncture was applied at"Bǎihuì(百会GV20)"and"Dàzhuī(大椎GV14)".Transmission electron microscope(TEM)was adopted to observe neuronal apoptosis in the rats.The effect of acupuncture on anti-neuronal apoptosis was compared.Using reverse transcription-polymerase chain reaction(RT-PCR)and western blot methods,the mRNA and protein expressions of PI3 K and AKT were detected in ventral tegmental area(VTA).Results:It was found that edema was presented in VTA neuronal cytoplasm and organelles basically disappeared in the heroin relapse rats,nuclear chromatin aggregation,condensation and increased neuronal apoptosis were presented as well.After acupuncture at"Bǎihuì(百会GV20)"and"Dàzhuī(大椎GV14)",a small amount of mitochondria,rough endoiplasmic reticulum and glycogen granules were visible in the cytoplasm of VTA neurons.The nuclear membrane structure was clear and the chromatin in the nucleus was basically normal.The fluorescence quantitative polymerase chain reaction(PCR)and western blot methods were adopted to detect mRNA and protein expressions of PI3K and AKT.It was found that the mRNA and protein expressions of PI3K and AKT in the brain of the rats in the model group were lower than those in the normal group(all P<0.05).Compared with the model group,the mRNA and protein expressions of PI3K and AKT in the acupuncture group were increased(all P<0.05),tending to the levels as the normal group.Conclusion:The effect of acupuncture on anti-brain cell apoptosis in heroin relapse rats may be related to the inhibition of PI3K/AKT signaling pathway.
文摘γ-amidobutyric acid (GABA) is a major inhibitory neurotransmitter in the central nervous system and mediates fast synaptic inhibition through GABAA and GABAC
基金Special Funds for Major State Basic Research Program of China (973 Program), 2006CB500706Scientific Research Common Program of Beijing Municipal Commission of Education, No. KM200610025002
文摘BACKGROUND： Aggregation of α-synuclein is the major component of Lewy bodies, which are the pathological hallmarks of Parkinson disease （PD）. Although the mechanism of this protein aggregates is unclear, previous study showed that environmental toxins such as rotenone could induce the expression and aggregation of α-synuclein. OBJECTIVE： To observe the role of α-synuclein in PD.DESIGN ： A randomized controlled trial.SETTING ： Beijing Institute for Neuroscience, Capital University of Medical Sciences.MATERIALS ： This study was performed from July 2005 to January 2006 at the Beijing Institute for Neuroscience, Capital University of Medical Sciences. Human dopaminergic neuroblastoma SH-SY5Y cells were provided by Beijing Institute for Neuroscience, Capital University of Medical Sciences. METHODS： Human dopaminergic neuroblastoma SH-SY5Y cells were treated to make α-synuclein over express. Rotenone was added into the medium of cultured both native SH-SY5Y cells and α-synuclein-overexpression SH-SY5Y cells. Lactate dehydrogenase （LDH） assay was used to detect with the cell viability. Flow cytometry and electrophoresis were adopted to measure the cell apoptosis. MAIN OUTCOME MEASURES ： Cell viability, DNA fragmentation, and the number of cell apoptosis.RESULTS： After being treated with rotenone, LDH activity of α-synuclein overexpressed SH-SY5Y cells was （76.625±6.34） μkat/L, which was significantly lower than that of control group （P 〈 0.05）. As compared with normal SH-SY5Y cell, α-synuclein over-expressed SH-SY5Y cells had less DNA fragments and apoptotic cells, α-synuclein might play a role in cell apoptosis induced by rotenone, which was also confirmed by using of antioxidant reagent. CONCLUSION： α-synuclein may partially protect against cell apoptosis induced by rotenone in SH-SY5Y cells.
基金the Topic of Science and Technology Department of Qingdao City, No.2005kzd-22
文摘BACKGROUND： Aquaporin-4 （AQP-4） is closely related to the formation of brain edema. Neuronal apoptosis plays an important part in the conversion of swelled neuron following traumatic brain injury. At present, the studies on the protective effect of ketamine on brain have involved in its effect on aquaporin-4 expression and neuronal apoptosis in the brain tissues following brain injury in rats. OBJECTIVE： To observe the effect of ketamine on AQP-4 expression and neuronal apoptosis in the brain tissue following rat brain injury, and analyze the time-dependence of ketamine in the treatment of brain injury.DESIGN： Randomized grouping design, controlled animal tria SETTING ： Department of Anesthesiology, the Medical School Hospital of Qingdao University MATERIALS： Totally 150 rats of clean grade, aged 3 months, were involved and randomized into control group and ketamine-treated group, with 75 rats in each. Each group was divided into 5 subgroups separately at 6,12, 24, 48 and 72 hours after injury, with 15 rats at each time point. Main instruments and reagents： homemade beat machine, ketamine hydrochloride （Hengrui Pharmaceutical Factory, Jiangsu）, rabbit anti-rat AQP-4 polyclonal antibody, SABC immunohistochemical reagent kit and TUNEL reagent kit （Boster Co.,Ltd., Wuhan）. METHODS： This trial was carried out in the Institute of Cerebrovascular Disease, Medical College of Qingdao University during March 2005 to February 2006. A weight-dropping rat model of brain injury was created with Feeney method. The rats in the ketamine-treated group were intraperitoneally administered with 50 g/L ketamine （120 mg/kg） one hour after injury, but ketamine was replaced by normal saline in the control group. In each subgroup, the water content of cerebral hemisphere was measured in 5 rats chosen randomly. The left 10 rats in each subgroup were transcardiacally perfused with ketamine, then the brain tissue was made into paraffin sections and stained by haematoxylin and eosin. Neuronal morphology was observed. AQP-4 expression and neuronal apoptosis were measured with immunohistochemical method and TUNEL method respectively. MAIN OUTCOME MEASURES： Water content in brain tissue, neuronal morphology, the number of AQP-4 positive neurons and TUNEL positive neurons in rats of two groups at each time point after injury. RESULTS： Totally 150 rats entered the stage of result analysis. （1） Water content of brain tissue： The water content of brain tissue at each time point after injury in the ketamine-treated group was lower than that in the control group. There were very significant differences in water content at 12 and 24 hours after injury respectively between ketamine-treated group and control group [（77.34±2.35）% vs. （82.31 ±1.48）%; （78.01 ±2.21 ）% vs. （83.86±2.37）%, t=-4.001 6,4.036 7, both P 〈 0.01]. （2） Neuronal morphology： Pathological changes in traumatic region and peripheral region of injury in the ketamine-treated group were significantly lessened, and necrotic and apoptotic cells in the ketamine-treated group were also significantly reduced as compared with control group. （3） AQP-4 expression： AQP-4 positive neurons at each time point in the ketamine-treated group were significantly less than those in the control group. There were very significant differences in AQP-4 expression at 12 and 24 hours after injury between ketamine-treated group and control group [（34.17±4.74） /visual field vs. （43.42±5.65） /visual field;（40.83±3.17） /visual field vs. （58.88±6.23） /visual field,t=3.966 3,8.165 7, both P〈 0.01]. （4） Neuronal apoptosis： TUNEL positive neurons at each time point in the ketamine-treated group were less than those in the control group. There were very significant differences in the neuronal apoptosis at 12 and 24 hours after injury between ketamine-treated group and control group [（26.25±3.04） /visual field vs. （32.75±4.39） /visual field; （29.33± 4.02） /visual field vs. （39.83±5.61） /visual field,t=-3.849 3,5.169 2,both P 〈 0.01]. CONCLUSION： Ketamine can reduce brain edema, AQP-4 expression and neuronal apoptosis following brain injury in rats, and has obvious therapeutic effect on brain injury, especially at 12 and 24 hours after injury.
文摘BACKGROUND： It is proved that the onset of Parkinson disease companies with neuronal apoptosis of dopamine in substantia nigra of midbrain. Previous researches on neuronal apoptosis of dopamine were analyzed on their consecutive tissue sections with immunohistochemical single-labeling method, immunofluorescence and electron microscope, and there are significant differences.OBJECTIVE ： To observe the feasibility of neuronal apoptosis of dopamine with in situ end labeling and tyrosine-hydroxylase antibody immunohistochemical double-labeling staining technique.DESIGN ： Controlled study.SETTING： College of Pharmacology of Taishan Medical College; College of Management of Taishan Medical College. MATERIALS ： Wistar rats with 2 weeks old and of clean grade were provided by the Animal Center of Taishan Medical College. In situ end labeling kit （terminal deoxynucleotidyl transferase, mixed reactive solution of nucleotide, transfusion-POD）, monoclonal antibody of rat antibody against tyrosine hydroxylase （Boehriuser）. METHODS： The experiment was completed at the Pharmacological Laboratory of Taishan Medical College from February to December 2005. Tissue from midbrain of rats was taken out to make paraffin sections to observe the neuronal apoptosis of dopamine under microscope with in situ end labeling and tyrosine-hydroxylase antibody immunohistochemical double-labeling staining technique.MAIN OUTCOME MEASURES ： Neuronal apoptosis of dopamine with in situ end labeling and tyrosine-hydroxylase antibody immunohistochemical double-labeling staining technique. RESULTS： ① After double-labeling staining, two kinks of positive products were observed in neurons of dopamine which were suffered from apoptosis. One stained with tyrosine hydroxylase was hyacinthine, and the other stained with in situ end labeling was buffy. Cells of positive products stained with in situ end labeling shaped as strap and bend and was distributed in clustering. Cytoplasm was hyacinthine, staining was symmetrical, and cellular ecphyma was observed. Nucleus was stained vacantly which was coincidence with form of neurons of dopamine. ②Apoptosis showed strictly in cytoplasm and nucleus at the aspect of morphology. Cytoplasm stained with in situ end labeling was hardly to recognize because of the usage of double-labeling staining technique, but nucleus was still characterized by apoptosis. The behavior of positive products stained with in situ end labeling was described as following： nucleus was buffy; karyopycnosis was round and irregular; caryotin was integrated into clump which was distributed at the border of nucleus and shaped as demilune and anular; positive signals were limited in nucleus and coincidence with morphological changes of apoptosis. However, blue and positive products were observed in cytoplasm of neurons of dopamine which did not occur apoptosis, and the nucleus was not labeled. Therefore, processing apoptosis of neurons of dopamine could be recognized. CONCULSION： Double-labeling staining technique can be used to correctly reveal histological and morphological changes of neuronal apoptosis of dopamine during its onset and development.
基金the Natural Science Fund of Shandong Province, No.Y2001C04
文摘BACKGROUND: It has been demonstrated that adenosine can induce glial cell to release cytochrome C, enhance expression of apoptotic gene bax, inhibit anti-apoptotic gene bcl-2, and activate caspase-3 to apoptosis; Whereas inosine can inhibit neuronal apoptosis which is similar to bcl-2. OBJECTIVE: To observe the effects of inosine on neuronal apoptosis and expression of cytochrome C mRNA in rats after focal cerebral ischemia/reperfusion, and analyze the pathway of its neuroprotective effect. DESIGN: A randomised controlled animal trial. SETTINGS: Department of Neurology, Rongcheng Second People's Hospital; Department of Neurology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. MATERIALS: Sixty-eight rats, weighing 230-280 g and clean grade, were used. TdT-mediated dUTP-biotin nick end labeling (TUNEL) and cytochrome C mRNA in situ hybridization kits and DAB staining kit were purchased from Wuhan Boster Biological Co., Ltd.; Inosine injection [200 mg (2 mL) each] from Qingdao First Pharmaceutical Factory. METHODS: The experiment was accomplished in the animal experimental center in Tongji Medical College of Huazhong University of Science and Technology from December 2003 to June 2005. ① Sixty-four rats were made into focal ischemia by middle cerebral artery occlusion (MCAO) with a nylon monofilament suture. The successfully induced rats were assigned to inosine group (n =32) and model group (n =32) at random. Rats in the inosine group were intraperitoneally administrated with inosine in dose of 100 mg/kg preoperatively, twice a day, 7 days in all. The rats in the control group were injected with the same dose of saline solution by the similar way preoperatively. Each group was randomized into ischemia /reperfusion 2, 6, 12, 24 hours, 2, 3, 7 and 14 days subgroups consisted of 4 rats. The other 4 rats were taken as the sham-operated group, the rats were given the same treatment except for not introduced the filament into the external carotid artery stump, and brain tissue was removed at 2 hours of reperfusion. ② In situ hybridization was performed to examine the expression of cytochrome C mRNA while TUNEL staining was made to characterize apoptosis. ③ The t test was used to compare the difference of measurement data. MAIN OUTCOME MEASURES: ① Neuronal apoptosis in the different regions of the ischemic brain tissue; ② Expression of cytochrome C mRNA in the different regions at different time points after MCAO. RESULTS: All the 68 rats were involved in the analysis of results. ① Neuronal apoptosis: A small number of TUNEL-positive cells were detected in the sham-operated brain and non-ischemic brain. The number of apoptotic cells in the ischemic cortex peaked at 24 hours of reperfusion [(72.00±1.98) cells] and that in the striatum peaked at 2 days [(94.75±3.57) cells], then decreased to the level of sham-operated group at 14 days. Inosine could reduce apoptotic cells from 12 hours to 7 days of reperfusion as compared with the model group (t =6.19-26.67, P < 0.01). ② Cytochrome C mRNA expression: There was weak expression of cytochrome C mRNA in both sham-operated brain and contralateral brain. Cytochrome C was detected at 2 hours of reperfusion in ischemic brain [(25.75±3.50), (39.75±2.49) cells], and strongly increased to a peak at 12 hours and 24 hours of reperfusion in cortex and striatum [(122.50±6.69), (119.25±5.12) cells], respectively. Furthermore, inosine could significantly decrease cytochrome C expression in cortex at 12 hours to 14 days of reperfusion after ischemic reperfusion and that in striatum at 12 hours to 3 days (t =8.67-43.26, P < 0.01). CONCLUSION: Inosine can exert a neuroprotective effect by inhibiting apoptosis and cytochrome C mRNA expression.
