Synaptic plasticity is essential for maintaining neuronal function in the central nervous system and serves as a critical indicator of the effects of neurodegenerative disease.Glaucoma directly impairs retinal ganglio...Synaptic plasticity is essential for maintaining neuronal function in the central nervous system and serves as a critical indicator of the effects of neurodegenerative disease.Glaucoma directly impairs retinal ganglion cells and their axons,leading to axonal transport dysfuntion,subsequently causing secondary damage to anterior or posterior ends of the visual system.Accordingly,recent evidence indicates that glaucoma is a degenerative disease of the central nervous system that causes damage throughout the visual pathway.However,the effects of glaucoma on synaptic plasticity in the primary visual cortex remain unclear.In this study,we established a mouse model of unilateral chronic ocular hypertension by injecting magnetic microbeads into the anterior chamber of one eye.We found that,after 4 weeks of chronic ocular hypertension,the neuronal somas were smaller in the superior colliculus and lateral geniculate body regions of the brain contralateral to the affected eye.This was accompanied by glial cell activation and increased expression of inflammatory factors.After 8 weeks of ocular hypertension,we observed a reduction in the number of excitatory and inhibitory synapses,dendritic spines,and activation of glial cells in the primary visual cortex contralateral to the affected eye.These findings suggest that glaucoma not only directly damages the retina but also induces alterations in synapses and dendritic spines in the primary visual cortex,providing new insights into the pathogenesis of glaucoma.展开更多
Nonalcoholic fatty liver disease(NAFLD) and type 2 Diabetes Mellitus(T2 DM) are highly prevalent diseases and are closely associated, with NAFLD being present in the majority of T2 DM patients. In Asian traditional me...Nonalcoholic fatty liver disease(NAFLD) and type 2 Diabetes Mellitus(T2 DM) are highly prevalent diseases and are closely associated, with NAFLD being present in the majority of T2 DM patients. In Asian traditional medicine, Mori Cortex is widely used for the treatment of diabetes and hyperlipidemia. However, whether it has a therapeutic effect on T2 DM associated with NAFLD is still unknown. The present study showed that the oral treatment with Mori Cortex extract(MCE; 10 g·kg-1·d-1) lowered the blood lipid levels and reversed insulin resistance(IR) in high fat-diet/streptozotocin-induced type 2 diabetes in rats. The expression levels of sterol receptor element-binding protein-1 c(SREBP-1 c) and carbohydrate-responsive element binding protein(Ch REBP), which are involved in steatosis in NAFLD rats, were measured in the liver samples. MCE decreased the protein and m RNA expression levels of SREBP-1 c and Ch REBP. In conclusion, down-regulation of SREBP-1 c and Ch REBP might contribute to the protective effect of MCE on hepatic injury and IR in the rats with T2 DM associated with NAFLD.展开更多
In the present study expression of estrogen receptor subtype -alpha (ERalpha) and -beta (ERbeta) in the cerebral cortex, cerebellum, and olfactory bulb was investigated and compared between neonatal (1 to approximatel...In the present study expression of estrogen receptor subtype -alpha (ERalpha) and -beta (ERbeta) in the cerebral cortex, cerebellum, and olfactory bulb was investigated and compared between neonatal (1 to approximately 3-days-old) and adult (250 to approximately 350 g) rats, using reverse transcription-polymerase chain reaction (RT-PCR). No ERalpha transcripts were detectable in the adult cerebellum and olfactory bulb, whereas very weak expression of ERalpha was present in the adult cerebral cortex. No significant difference in ERbeta transcripts was detectable between the neonatal and adult rats. While transcripts for both ER subtypes were co-expressed in these brain areas of neonatal rats, although ERalpha expression was significantly weaker than ERbeta. Even in the cerebral cortex known to contain both ER subtypes in adult rats, ERalpha transcripts in neonatal rats were much higher than in adult. These observations provide evidence for the existence of different expression patterns of ERalpha/ERbeta transcripts in these three brain areas between the neonatal and adult rats, suggesting that each ER subtype may play a distinct role in the regulation of differentiation, development, and functions of the brain by estrogen.展开更多
Pain is often comorbid with emotional disorders such as anxiety and depression.Hyperexcitability of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairme...Pain is often comorbid with emotional disorders such as anxiety and depression.Hyperexcitability of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid neurotransmission.This review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain disorders.Improving understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these conditions.However,the mechanisms that regulate gamma-aminobutyric acidergic systems remain elusive.It is also unclear as to whether the mechanisms are presynaptic or postsynaptic.Further exploration of the complexities of this system may reveal new pathways for research and drug development.展开更多
The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate ne...The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.展开更多
Spinal cord injury typically causes corticospinal tract disruption.Although the disrupted corticospinal tract can self-regenerate to a certain degree,the underlying mechanism of this process is still unclear.N6-methyl...Spinal cord injury typically causes corticospinal tract disruption.Although the disrupted corticospinal tract can self-regenerate to a certain degree,the underlying mechanism of this process is still unclear.N6-methyladenosine(m^(6)A)modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes.However,whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown.We found that expression of methyltransferase 14 protein(METTL14)in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels.Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury.Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction,we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner,thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration.Finally,we administered syringin,a stabilizer of METTL14,using molecular docking.Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14.Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.展开更多
The dysfunction of the medial prefrontal cortex is associated with affective disorders and non-motor features in Parkinson’s disease.However,the exact role of the mediodorsal thalamic nucleus in the function of the p...The dysfunction of the medial prefrontal cortex is associated with affective disorders and non-motor features in Parkinson’s disease.However,the exact role of the mediodorsal thalamic nucleus in the function of the prefrontal cortex remains unclear.To study the possible effects of the mediodorsal thalamic nucleus on the neurological function of the medial prefrontal cortex,a model of Parkinson’s disease was established by injecting 8μg 6-hydroxydopamine into the substantia nigra compacta of rats.After 1 or 3 weeks,0.3μg ibotenic acid was injected into the mediodorsal thalamic nucleus of the midbrain.At 3 or 5 weeks after the initial injury,neuronal discharge in medial prefrontal cortex of rat brain was determined electrophysiologically.The numbers of dopamine-positive neurons and tyrosine hydroxylase immunoreactivity in substantia nigra compacta and ventral tegmental area were detected by immunohistochemical staining.Results demonstrated that after injury,the immunoreactivity of dopamine neurons and tyrosine hydroxylase decreased in the substantia nigra compacta and ventral tegmental areas of rats.Compared with normal medial prefrontal cortical neurons,at 3 and 5 weeks after substantia nigra compacta injury,the discharge frequency of pyramidal neurons increased and the discharge pattern of these neurons tended to be a burst-discharge,with an increased discharge interval.The discharge frequency of interneurons decreased and the discharge pattern also tended to be a burst-discharge,but the discharge interval was only higher at 3 weeks.At 3 weeks after the combined lesions,the discharge frequency,discharge pattern and discharge interval were restored to a normal level in pyramidal neurons and interneurons in medial prefrontal cortex.These findings have confirmed that mediodorsal thalamic nucleus is involved in regulating neuronal activities of the medial prefrontal cortex.The changes in the function of the mediodorsal thalamic nucleus may be associated with the abnormal discharge activity of the medial prefrontal cortex neurons after substantia nigra compacta injury.All experimental procedures were approved by the Institutional Animal Care and Use Committee of Xi’an Jiaotong University,China(approval No.XJTULAC2017-067)on August 26,2017.展开更多
The multiple-layer structure of the cerebral cortex is important for its functions. Such a structure is generated based on the proliferation and differentiation of neural stem/progenitor cells. Notch functions as a mo...The multiple-layer structure of the cerebral cortex is important for its functions. Such a structure is generated based on the proliferation and differentiation of neural stem/progenitor cells. Notch functions as a molecular switch for neural stem/progenitor cell fate during cortex development but the mechanism remains unclear. Biochemical and cellular studies showed that Notch receptor activation induces several proteases to release the Notch intracellular domain （NICD）. A Disintegrin and Metalloprotease 10 （ADAM10） might be a physiological rate-limiting $2 enzyme for Notch activation. Nestin-driven conditional ADAM10 knockout in mouse cortex showed that ADAM10 is cdtical for maintenance of the neural stem cell population during early embryonic cortex development. However, the expression pattern and function of ADAM10 during later cerebral cortex development remains poorly understood. We performed in situ hybridization for ADAMIO mRNA and immunofluorescent analysis to determine the expression of ADAM10 and NICD in mouse cortex from embryonic day 9 （E14.5） to postnatal day 1 （P1）. ADAM10 and NICD were highly co-localized in the cortex of E16.5 to P1 mice. Comparisons of expression patterns of ADAM10 with Nestin （neural stem cell marker）, Tujl （mature neuron marker）, and S100β （gila marker） showed that ADAM10 expression highly matched that of S10013 and partially matched that of Tujl at later embryonic to early postnatal cortex developmental stages. Such expression patterns indicated that ADAM10-Notch signaling might have a critical function in neuronal maturation and gliogenesis during cortex development.展开更多
Humans are limited in their ability to perform multiple cognitive-motor tasks in parallel. In eight participants, we examined whether transcranial direct current stimulation (tDCS) to dorsal premotor cortex (PMD) coul...Humans are limited in their ability to perform multiple cognitive-motor tasks in parallel. In eight participants, we examined whether transcranial direct current stimulation (tDCS) to dorsal premotor cortex (PMD) could attenuate a delay of reaction time (RT) while the participants responded to two visual stimuli presented in temporally close succession. We provided anodal, cathodal, or sham tDCS while the participants performed a task requiring two choice responses or a control task requiring two fixed responses. When the interval between the two stimuli was shorter, the RTs were delayed in both tasks, but anodal tDCS shortened them only in the former task, probably by promoting the response selection function of PMD. Non-invasive neuro-modulation to the brain can boost human ability to multi-task.展开更多
This study aimed to investigate the association between atrophy in the prefrontal cortex with executive function and verbal fluency in elderly male and female patients poststroke. Thirty elderly female patients with n...This study aimed to investigate the association between atrophy in the prefrontal cortex with executive function and verbal fluency in elderly male and female patients poststroke. Thirty elderly female patients with non-aphasic ischemic stroke aged -〉 60 years and 30 age-matched non-aphasic male patients with ischemic stroke were recruited. Automatic magnetic resonance imaging segmentation was used to assess the volume of the whole prefrontal cortex, along with its subdivisions： anterior cingulate cortex, orbitofrontal cortex and dorsolateral prefrontal cortex. The Semantic Verbal Fluency Test was administered at 3 and 15 months poststroke. At 3 months poststroke, left dorsolateral prefrontal cortex volume was significantly correlated with Verbal Fluency Test score in female patients only （partial coefficient = 0.453, P = 0.045）, after controlling for age, education, diabetes, neurological deficit, white matter lesions volume, as well as the location and volume of infarcts. At 15 months poststroke, there remained a significant association between the left dorsolateral prefrontal cortex volume and Verbal Fluency Test （partial coefficient = 0.661, P = 0.001） and between the left prefrontal cortex volume and Verbal Fluency Test （partial coefficient = 0.573, P = 0.004） in female patients after the same adjustments. These findings indicate that atrophy of the left dorsolateral prefrontal cortex contributes to the impairment of verbal fluency in elderly female patients with stroke. Sex differences may be present in the neuropsychological mechanisms of verbal fluency impairment in patients with stroke.展开更多
BACKGROUND The major reason for filtering bleb failure or scarring of the bleb site is due to excessive scarring after glaucoma filtration surgery in the clinic.Traditional Chinese medicine has preeminence in the prev...BACKGROUND The major reason for filtering bleb failure or scarring of the bleb site is due to excessive scarring after glaucoma filtration surgery in the clinic.Traditional Chinese medicine has preeminence in the prevention of fibrosis formation through the regulation of systemic circulation and improvement of the properties of the inflammatory cells in the blood.AIM To examine the clinical efficacy of using the Modified Cortex Mori Capsules(MCMC;Chinese name:Jiawei Sangbaipi Capsules)in the success rate of functional filtering blebs after glaucoma filtering surgery in clinical patients.METHODS Sixty resurgery glaucoma patients were randomly divided into two groups:30 patients in surgery with the placebo group and 30 patients in surgery with the MCMC group.Patients took either the placebo or the MCMC 2 wk before and after surgery.Postoperative morphology and function filtering bleb,visual acuity,intraocular pressure,postoperative complications,the success rate of filtration surgery and clinical efficacy were observed.RESULTS Fifty patients completed the study.The percentage of functional filtering blebs in the surgery plus MCMC group was 84%at 6 mo after surgery,which was higher than surgery plus placebo group(64%,P<0.05).The surgical success rate in the MCMC and placebo groups were 79%±8.3%and 57%±10.6%respectively(P<0.05).The visual acuity,intraocular pressure and the postoperative complications in the two groups had no significant differences.CONCLUSION Glaucoma filtering surgery while taking MCMC not only reduced excessive scar formation and increased the success rate of functional filtering blebs but also improved the success of glaucoma filtration operations.展开更多
Background: The primary motor cortex (M1) stimulation (MCS) is a useful tool for attenuation of the peripheral neuropathic pain in patients with pharmacologically refractory pain. Furthermore, that neurological proced...Background: The primary motor cortex (M1) stimulation (MCS) is a useful tool for attenuation of the peripheral neuropathic pain in patients with pharmacologically refractory pain. Furthermore, that neurological procedure may also cause antinociception in rodents with neuropathic pain. Cold allodynia is a frequent clinical finding in patients with neuropathic pain, then, we evaluated if an adapted model of neuropathy induced by chronic constriction injury (CCI) of the ischiadicus nervus (sciatic nerve) produces cold allodynia in an animal model of chronic pain. In addition, we also investigated the effect of the electrical stimulation of the M1 on chronic neuropathic pain condition in laboratory animals. Methods: Male Wistar rats were used. An adapted model of peripheral mononeuropathy induced by CCI was carried out by placing a single loose ligature around the right sciatic nerve. The acetone test was used to evaluate the cold allodynia in CCI or Sham (without ligature) rats. The MCS (M1) was performed at low-frequency (20 μA, 100 Hz) during 15 s by deep brain stimulation (DBS-Thomas Recording device) 21 days after CCI or Sham procedures. The cold allodynia was measured before and immediately after the neurostimulation of M1 in the following time-window: 0, 15 and 30 min after MCS. Results: Cold allodynia threshold increased in animals with chronic neuropathic pain submitted to the acetone test 21 days after the CCI surgery. The M1-stimulation by DBS procedure decreased the cold allodynia immediately and until 30 min after M1-stimulation in rats with chronic neuropathic pain. Conclusion: The current proposal for a CCI model by a single loose ligature of the sciatic nerve can be employed as an experimental model of chronic neuropathic pain in rats submitted to peripheral nervous system injury. The M1-stimulation produced antinociception in rats with chronic neuropathic pain. Thus, we reinforced that the MCS decreases cold allodynia in laboratory animals submitted to persistent sciatic nerve constriction and can be a more reasonable procedure for the treatment of chronic intractable neuropathic pain.展开更多
Dear Editor,The importance of the medial entorhinal cortex(MEC)for memory and spatial navigation has been shown repeatedly in many species,including mice and humans[1,2].It is,therefore,not surprising that the connect...Dear Editor,The importance of the medial entorhinal cortex(MEC)for memory and spatial navigation has been shown repeatedly in many species,including mice and humans[1,2].It is,therefore,not surprising that the connectivity of this structure has been studied extensively over the past century,mainly using a range of anterograde and retrograde anatomical tracers[3].展开更多
The dorsal area of the anterior cingulate cortex (ACC) constructs the salience network associated with the anterior insular cortex. Conventional brain imaging studies, such as functional magnetic resonance imaging (fM...The dorsal area of the anterior cingulate cortex (ACC) constructs the salience network associated with the anterior insular cortex. Conventional brain imaging studies, such as functional magnetic resonance imaging (fMRI), have demonstrated that relational memory formation occurs in the ACC. However, how such memory is encoded and retrieved remains unknown due to limited time resolution of conventional fMRI. This study aimed to investigate temporal dynamics of the dorsal ACC (dACC) during word-pair tasks based on a newly developed event-related deep brain activity (ER-DBA) method using occipital electroencephalogram (EEG) signal powers. The method assesses dACC activity at a temporal resolution of approximately 0.3 s beyond the conventional resolution limit. We found that transient deactivation of dACC during the presentation of the second word of each pair was essential for encoding success regardless of whether the words were related or unrelated. We also found that memory accuracy was not affected by the intervention of inter-trials until the recall trial. Taken together, these findings suggest that dACC deactivation for encoding success is accompanied with short-term potentiation essential for durability of memory. We further found that false memory formation associated with the presentation of word pairs was occasionally committed. In such cases, dACC exhibited a similar transient deactivation although false memory commission was independent of related or unrelated conditions. Our findings suggest that encoding and retrieval of associates are paralleled and that simultaneous production of associates seems to be an essential strategy for successful relational memory formation. The study was limited to the assessment of dACC activity and did not account for other regional brain activities or receptor regulation related to short-term potentiation. We detected fast behavior of dACC during relational memory formation using the novel ER-DBA method. Such temporal dynamics will be important for eliciting underlying mechanisms of memory dysfunctions.展开更多
Pain consists of sensory-discriminative and emotional-affective components.The anterior cingulate cortex(ACC)is a critical brain area in mediating the affective pain.However,the molecular mechanisms involved remain la...Pain consists of sensory-discriminative and emotional-affective components.The anterior cingulate cortex(ACC)is a critical brain area in mediating the affective pain.However,the molecular mechanisms involved remain largely unknown.Our recent study indicated that C-X-C motif chemokine 13(CXCL13)and its sole receptor CXCR5 are involved in sensory sensitization in the spinal cord after spinal nerve ligation(SNL).Whether CXCL13/CXCR5 signaling in the ACC contributes to the pathogenesis of pain-related aversion remains unknown.Here,we showed that SNL increased the CXCL13 level and CXCR5 expression in the ACC after SNL.Knockdown of CXCR5 by microinjection of Cxcr5 shRNA into the ACC did not affect SNL-induced mechanical allodynia but effectively alleviated neuropathic painrelated place avoidance behavior.Furthermore,electrophysiological recording from layer Ⅱ-Ⅲ neurons in the ACC showed that SNL increased the frequency and amplitude of spontaneous excitatory postsynaptic currents(sEPSCs),decreased the EPSC paired-pulse ratio,and increased the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor/N-methyl-D-aspartate receptor ratio,indicating enhanced glutamatergic synaptic transmission.Finally,superfusion of CXCL13 onto ACC slices increased the frequency and amplitude of spontaneous EPSCs.Pre-injection of Cxcr5 shRNA into the ACC reduced the increase in glutamatergic synaptic transmis sion induced by SNL.Collectively,these results suggest that CXCL13/CXCR5 signaling in the ACC is involved in neuropathic pain-related aversion via synaptic potentiation.展开更多
Orexins, produced in the lateral hypothalamus, are important neuropeptides that participate in the sleep/wake cycle, and their expres- sion coincides with the projection area of the vagus nerve in the brain. Vagus ner...Orexins, produced in the lateral hypothalamus, are important neuropeptides that participate in the sleep/wake cycle, and their expres- sion coincides with the projection area of the vagus nerve in the brain. Vagus nerve stimulation has been shown to decrease the amounts of daytime sleep and rapid eye movement in epilepsy patients with traumatic brain injury. In the present study, we investigated whether vagus nerve stimulation promotes wakefulness and affects orexin expression. A rat model of traumatic brain injury was established using the free fall drop method. In the stimulated group, rats with traumatic brain injury received vagus nerve stimulation （frequency, 30 Hz, current, 1.0 mA; pulse width, 0.5 ms; total stimulation time, 15 minutes）. In the antagonist group, rats with traumatic brain injury were intracerebroventricularly injected with the orexin receptor type 1 （OXIR） antagonist SB334867 and received vagus nerve stimulation. Changes in consciousness were observed after stimulation in each group. Enzyme-linked immunosorbent assay, western blot assay and immunohistochemistry were used to assess the levels of orexin-A and OX1R expression in the prefrontal cortex. In the stimulated group, consciousness was substantially improved, orexin-A protein expression gradually increased within 24 hours after injury and OX1R expres- sion reached a peak at 12 hours, compared with rats subjected to traumatic brain injury only. In the antagonist group, the wake-promoting effect of vagus nerve stimulation was diminished, and orexin-A and OX1R expression were decreased, compared with that of the stim- ulated group. Taken together, our findings suggest that vagus nerve stimulation promotes the recovery of consciousness in comatose rats after traumatic brain injury. The upregulation of orexin-A and OXIR expression in the prefrontal cortex might be involved in the wake-promoting effects of vagus nerve stimulation.展开更多
The effects of electrical stimulation of second somatosensory area(S Ⅱ)andelectroacupuncture(EA)at Huantiao(GB 30)and Yanglinquan(GB 34)points on nociceptive re-sponses of neurons in the nucleus centrum medianum(CM)i...The effects of electrical stimulation of second somatosensory area(S Ⅱ)andelectroacupuncture(EA)at Huantiao(GB 30)and Yanglinquan(GB 34)points on nociceptive re-sponses of neurons in the nucleus centrum medianum(CM)in the thalamus were respectively ob-served after topical application of bicuculline(Bic)at the motor cortex(MCtx),and the results werecompared with those obtained in the saline control group.It was found that following application ofBic either electrical stimulation of SII(n=11)or EA(n=11)yielded obvious inhibition on nocicep-tive responses of CM neurons(P【0.05),which was similar to the inhibitory effects obtained in thesaline control groups(n=11,n=10).After GABA application at MCtx electrical stimulation of SIIfailed to show inhibition on nociceptive responses in 3 CM neurons.It is indicated that GABA in MC-tx is involved in SII originating corticofugal regulation of nucleus CM in acupuncture analgesia.展开更多
Previous studies have demonstrated that doublecortin-positive immature neurons exist pre- dominantly in the superficial layer of the cerebral cortex of adult mammals such as guinea pigs, and these neurons exhibit very...Previous studies have demonstrated that doublecortin-positive immature neurons exist pre- dominantly in the superficial layer of the cerebral cortex of adult mammals such as guinea pigs, and these neurons exhibit very weak properties of self-proliferation during adulthood under physiological conditions. To verify whether environmental enrichment has an impact on the proliferation and maturation of these immature neurons in the prefrontal cortex of adult guinea pigs, healthy adult guinea pigs were subjected to short-term environmental enrichment. Animals were allowed to play with various cognitive and physical stimulating objects over a period of 2 weeks, twice per day, for 60 minutes each. Immunofluorescence staining results indicated that the number of doublecortin-positive cells in layer II of the prefrontal cortex was significantly increased after short-term environmental enrichment exposure. In addition, these doublecortin-positive cells co-expressed 5-bromo-2-deoxyuridine （a marker of cell prolifera- tion）, c-Fos （a marker of cell viability） and NeuN （a marker of mature neurons）. Experimental findings showed that short-term environmental enrichment can induce proliferation, activation and maturation of doublecortin-positive cells in layer II of the prefrontal cortex of adult guinea pigs.展开更多
The development and plasticity of central auditory system can be influenced by the change of peripheral neuronal activity. However, the molecular mechanism participating in the process remains elusive. Brain-derived n...The development and plasticity of central auditory system can be influenced by the change of peripheral neuronal activity. However, the molecular mechanism participating in the process remains elusive. Brain-derived neurotrophic factor(BDNF) binding with its functional receptor tropomyosin receptor kinase B(TrkB) has multiple effects on neurons. Here we used a rat model of auditory deprivation by bilateral cochlear ablation, to investigate the changes in expression of BDNF and Trk B in the auditory cortex after auditory deprivation that occurred during the critical period for the development of central auditory system. Reverse transcription-quantitative polymerase chain reaction(RTqPCR) and immunohistochemistry methods were adopted to detect the m RNA and protein expression levels of BDNF and TrkB in the auditory cortex at 2, 4, 6 and 8 weeks after surgery, respectively. The change in the expression of BDNF and TrkB mRNAs and proteins followed similar trend. In the bilateral cochlear ablation groups, the BDNF-TrkB expression level initially decreased at 2 weeks but increased at 4 weeks followed by the reduction at 6 and 8 weeks after cochlear removal, as compared to the age-matched sham control groups. In conclusion, the BDNF-TrkB signaling is involved in the plasticity of auditory cortex in an activity-dependent manner.展开更多
To understand the connectivity of cerebral cor-tex, especially the spatial and temporal pattern of movement, functional magnetic resonance imaging (fMRI) during subjects performing finger key presses was used to extra...To understand the connectivity of cerebral cor-tex, especially the spatial and temporal pattern of movement, functional magnetic resonance imaging (fMRI) during subjects performing finger key presses was used to extract functional networks and then investigated their character-istics. Motor cortex networks were constructed with activation areas obtained with statistical analysis as vertexes and correlation coefficients of fMRI time series as linking strength. The equivalent non-motor cortex networks were constructed with certain distance rules. The graphic and dynamical measures of motor cor-tex networks and non-motor cortex networks were calculated, which shows the motor cortex networks are more compact, having higher sta-tistical independence and integration than the non-motor cortex networks. It indicates the motor cortex networks are more appropriate for information diffusion.展开更多
基金supported by the National Natural Science Foundation of China,No.82271115(to MY).
文摘Synaptic plasticity is essential for maintaining neuronal function in the central nervous system and serves as a critical indicator of the effects of neurodegenerative disease.Glaucoma directly impairs retinal ganglion cells and their axons,leading to axonal transport dysfuntion,subsequently causing secondary damage to anterior or posterior ends of the visual system.Accordingly,recent evidence indicates that glaucoma is a degenerative disease of the central nervous system that causes damage throughout the visual pathway.However,the effects of glaucoma on synaptic plasticity in the primary visual cortex remain unclear.In this study,we established a mouse model of unilateral chronic ocular hypertension by injecting magnetic microbeads into the anterior chamber of one eye.We found that,after 4 weeks of chronic ocular hypertension,the neuronal somas were smaller in the superior colliculus and lateral geniculate body regions of the brain contralateral to the affected eye.This was accompanied by glial cell activation and increased expression of inflammatory factors.After 8 weeks of ocular hypertension,we observed a reduction in the number of excitatory and inhibitory synapses,dendritic spines,and activation of glial cells in the primary visual cortex contralateral to the affected eye.These findings suggest that glaucoma not only directly damages the retina but also induces alterations in synapses and dendritic spines in the primary visual cortex,providing new insights into the pathogenesis of glaucoma.
基金supported by Ningbo Science and Technology Innovation Team Program(No.2014B82002)the National Natural Science Foundation of China(Nos.81370165,81501421,and 31301068)+1 种基金the Natural Science Foundation of Ningbo(Nos.2013A610209 and 2015A610217)Fang Runhua Fund of Hong Kong and K.C.Wong Magna Fund of Ningbo University
文摘Nonalcoholic fatty liver disease(NAFLD) and type 2 Diabetes Mellitus(T2 DM) are highly prevalent diseases and are closely associated, with NAFLD being present in the majority of T2 DM patients. In Asian traditional medicine, Mori Cortex is widely used for the treatment of diabetes and hyperlipidemia. However, whether it has a therapeutic effect on T2 DM associated with NAFLD is still unknown. The present study showed that the oral treatment with Mori Cortex extract(MCE; 10 g·kg-1·d-1) lowered the blood lipid levels and reversed insulin resistance(IR) in high fat-diet/streptozotocin-induced type 2 diabetes in rats. The expression levels of sterol receptor element-binding protein-1 c(SREBP-1 c) and carbohydrate-responsive element binding protein(Ch REBP), which are involved in steatosis in NAFLD rats, were measured in the liver samples. MCE decreased the protein and m RNA expression levels of SREBP-1 c and Ch REBP. In conclusion, down-regulation of SREBP-1 c and Ch REBP might contribute to the protective effect of MCE on hepatic injury and IR in the rats with T2 DM associated with NAFLD.
文摘In the present study expression of estrogen receptor subtype -alpha (ERalpha) and -beta (ERbeta) in the cerebral cortex, cerebellum, and olfactory bulb was investigated and compared between neonatal (1 to approximately 3-days-old) and adult (250 to approximately 350 g) rats, using reverse transcription-polymerase chain reaction (RT-PCR). No ERalpha transcripts were detectable in the adult cerebellum and olfactory bulb, whereas very weak expression of ERalpha was present in the adult cerebral cortex. No significant difference in ERbeta transcripts was detectable between the neonatal and adult rats. While transcripts for both ER subtypes were co-expressed in these brain areas of neonatal rats, although ERalpha expression was significantly weaker than ERbeta. Even in the cerebral cortex known to contain both ER subtypes in adult rats, ERalpha transcripts in neonatal rats were much higher than in adult. These observations provide evidence for the existence of different expression patterns of ERalpha/ERbeta transcripts in these three brain areas between the neonatal and adult rats, suggesting that each ER subtype may play a distinct role in the regulation of differentiation, development, and functions of the brain by estrogen.
基金supported by the National Natural Science Foundation of China,Nos.82374561(to JD),82174490(to JF)the Medical and Health Science and Technology Program of Zhejiang Province,No.2021RC098(to JD)the Research Project of Zhejiang Chinese Medical University,Nos.2022JKZKTS44(to JD),2022FSYYZZ07(to JF).
文摘Pain is often comorbid with emotional disorders such as anxiety and depression.Hyperexcitability of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid neurotransmission.This review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain disorders.Improving understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these conditions.However,the mechanisms that regulate gamma-aminobutyric acidergic systems remain elusive.It is also unclear as to whether the mechanisms are presynaptic or postsynaptic.Further exploration of the complexities of this system may reveal new pathways for research and drug development.
基金supported by the National Natural Science Foundation of China,Nos.82272171(to ZY),82271403(to XL),81941011(to XL),31971279(to ZY),31730030(to XL)the Natural Science Foundation of Beijing,No.7222004(to HD).
文摘The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.
基金supported by the National Natural Science Foundation of China,Nos.82030071(to JH),82272495(to YC)Science and Technology Major Project of Changsha,No.kh2103008(to JH)Graduate Students’Independent Innovative Projects of Hunan Province,No.CX20230311(to YJ)。
文摘Spinal cord injury typically causes corticospinal tract disruption.Although the disrupted corticospinal tract can self-regenerate to a certain degree,the underlying mechanism of this process is still unclear.N6-methyladenosine(m^(6)A)modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes.However,whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown.We found that expression of methyltransferase 14 protein(METTL14)in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels.Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury.Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction,we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner,thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration.Finally,we administered syringin,a stabilizer of METTL14,using molecular docking.Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14.Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.
基金supported by the Key Research Project of Science and Technology of Henan Province of China,No.14B180007(to LLF)the Development Project of Science and Technology of Luoyang Municipality of China,No.1401087A-5(to LLF)
文摘The dysfunction of the medial prefrontal cortex is associated with affective disorders and non-motor features in Parkinson’s disease.However,the exact role of the mediodorsal thalamic nucleus in the function of the prefrontal cortex remains unclear.To study the possible effects of the mediodorsal thalamic nucleus on the neurological function of the medial prefrontal cortex,a model of Parkinson’s disease was established by injecting 8μg 6-hydroxydopamine into the substantia nigra compacta of rats.After 1 or 3 weeks,0.3μg ibotenic acid was injected into the mediodorsal thalamic nucleus of the midbrain.At 3 or 5 weeks after the initial injury,neuronal discharge in medial prefrontal cortex of rat brain was determined electrophysiologically.The numbers of dopamine-positive neurons and tyrosine hydroxylase immunoreactivity in substantia nigra compacta and ventral tegmental area were detected by immunohistochemical staining.Results demonstrated that after injury,the immunoreactivity of dopamine neurons and tyrosine hydroxylase decreased in the substantia nigra compacta and ventral tegmental areas of rats.Compared with normal medial prefrontal cortical neurons,at 3 and 5 weeks after substantia nigra compacta injury,the discharge frequency of pyramidal neurons increased and the discharge pattern of these neurons tended to be a burst-discharge,with an increased discharge interval.The discharge frequency of interneurons decreased and the discharge pattern also tended to be a burst-discharge,but the discharge interval was only higher at 3 weeks.At 3 weeks after the combined lesions,the discharge frequency,discharge pattern and discharge interval were restored to a normal level in pyramidal neurons and interneurons in medial prefrontal cortex.These findings have confirmed that mediodorsal thalamic nucleus is involved in regulating neuronal activities of the medial prefrontal cortex.The changes in the function of the mediodorsal thalamic nucleus may be associated with the abnormal discharge activity of the medial prefrontal cortex neurons after substantia nigra compacta injury.All experimental procedures were approved by the Institutional Animal Care and Use Committee of Xi’an Jiaotong University,China(approval No.XJTULAC2017-067)on August 26,2017.
基金supported by the National Natural Science Foundation of China,No.30800322Shanghai Pujiang Program,No.08PJ1401300+4 种基金Shanghai Leading Academic Discipline Project,No.B111Ministry of Education Research Fund for New Teachers in Doctoral Program of Higher Educational Institutes,No.200802461050National Basic Research Program of China(973 Program),No.2011CB503703Ministry of Education Start Fund to Returned Overseas ScholarsZhuo Xue Program of Fudan University
文摘The multiple-layer structure of the cerebral cortex is important for its functions. Such a structure is generated based on the proliferation and differentiation of neural stem/progenitor cells. Notch functions as a molecular switch for neural stem/progenitor cell fate during cortex development but the mechanism remains unclear. Biochemical and cellular studies showed that Notch receptor activation induces several proteases to release the Notch intracellular domain （NICD）. A Disintegrin and Metalloprotease 10 （ADAM10） might be a physiological rate-limiting $2 enzyme for Notch activation. Nestin-driven conditional ADAM10 knockout in mouse cortex showed that ADAM10 is cdtical for maintenance of the neural stem cell population during early embryonic cortex development. However, the expression pattern and function of ADAM10 during later cerebral cortex development remains poorly understood. We performed in situ hybridization for ADAMIO mRNA and immunofluorescent analysis to determine the expression of ADAM10 and NICD in mouse cortex from embryonic day 9 （E14.5） to postnatal day 1 （P1）. ADAM10 and NICD were highly co-localized in the cortex of E16.5 to P1 mice. Comparisons of expression patterns of ADAM10 with Nestin （neural stem cell marker）, Tujl （mature neuron marker）, and S100β （gila marker） showed that ADAM10 expression highly matched that of S10013 and partially matched that of Tujl at later embryonic to early postnatal cortex developmental stages. Such expression patterns indicated that ADAM10-Notch signaling might have a critical function in neuronal maturation and gliogenesis during cortex development.
文摘Humans are limited in their ability to perform multiple cognitive-motor tasks in parallel. In eight participants, we examined whether transcranial direct current stimulation (tDCS) to dorsal premotor cortex (PMD) could attenuate a delay of reaction time (RT) while the participants responded to two visual stimuli presented in temporally close succession. We provided anodal, cathodal, or sham tDCS while the participants performed a task requiring two choice responses or a control task requiring two fixed responses. When the interval between the two stimuli was shorter, the RTs were delayed in both tasks, but anodal tDCS shortened them only in the former task, probably by promoting the response selection function of PMD. Non-invasive neuro-modulation to the brain can boost human ability to multi-task.
基金supported by the Research Grants Council of the Hong Kong SAR,No. 452906
文摘This study aimed to investigate the association between atrophy in the prefrontal cortex with executive function and verbal fluency in elderly male and female patients poststroke. Thirty elderly female patients with non-aphasic ischemic stroke aged -〉 60 years and 30 age-matched non-aphasic male patients with ischemic stroke were recruited. Automatic magnetic resonance imaging segmentation was used to assess the volume of the whole prefrontal cortex, along with its subdivisions： anterior cingulate cortex, orbitofrontal cortex and dorsolateral prefrontal cortex. The Semantic Verbal Fluency Test was administered at 3 and 15 months poststroke. At 3 months poststroke, left dorsolateral prefrontal cortex volume was significantly correlated with Verbal Fluency Test score in female patients only （partial coefficient = 0.453, P = 0.045）, after controlling for age, education, diabetes, neurological deficit, white matter lesions volume, as well as the location and volume of infarcts. At 15 months poststroke, there remained a significant association between the left dorsolateral prefrontal cortex volume and Verbal Fluency Test （partial coefficient = 0.661, P = 0.001） and between the left prefrontal cortex volume and Verbal Fluency Test （partial coefficient = 0.573, P = 0.004） in female patients after the same adjustments. These findings indicate that atrophy of the left dorsolateral prefrontal cortex contributes to the impairment of verbal fluency in elderly female patients with stroke. Sex differences may be present in the neuropsychological mechanisms of verbal fluency impairment in patients with stroke.
文摘BACKGROUND The major reason for filtering bleb failure or scarring of the bleb site is due to excessive scarring after glaucoma filtration surgery in the clinic.Traditional Chinese medicine has preeminence in the prevention of fibrosis formation through the regulation of systemic circulation and improvement of the properties of the inflammatory cells in the blood.AIM To examine the clinical efficacy of using the Modified Cortex Mori Capsules(MCMC;Chinese name:Jiawei Sangbaipi Capsules)in the success rate of functional filtering blebs after glaucoma filtering surgery in clinical patients.METHODS Sixty resurgery glaucoma patients were randomly divided into two groups:30 patients in surgery with the placebo group and 30 patients in surgery with the MCMC group.Patients took either the placebo or the MCMC 2 wk before and after surgery.Postoperative morphology and function filtering bleb,visual acuity,intraocular pressure,postoperative complications,the success rate of filtration surgery and clinical efficacy were observed.RESULTS Fifty patients completed the study.The percentage of functional filtering blebs in the surgery plus MCMC group was 84%at 6 mo after surgery,which was higher than surgery plus placebo group(64%,P<0.05).The surgical success rate in the MCMC and placebo groups were 79%±8.3%and 57%±10.6%respectively(P<0.05).The visual acuity,intraocular pressure and the postoperative complications in the two groups had no significant differences.CONCLUSION Glaucoma filtering surgery while taking MCMC not only reduced excessive scar formation and increased the success rate of functional filtering blebs but also improved the success of glaucoma filtration operations.
文摘Background: The primary motor cortex (M1) stimulation (MCS) is a useful tool for attenuation of the peripheral neuropathic pain in patients with pharmacologically refractory pain. Furthermore, that neurological procedure may also cause antinociception in rodents with neuropathic pain. Cold allodynia is a frequent clinical finding in patients with neuropathic pain, then, we evaluated if an adapted model of neuropathy induced by chronic constriction injury (CCI) of the ischiadicus nervus (sciatic nerve) produces cold allodynia in an animal model of chronic pain. In addition, we also investigated the effect of the electrical stimulation of the M1 on chronic neuropathic pain condition in laboratory animals. Methods: Male Wistar rats were used. An adapted model of peripheral mononeuropathy induced by CCI was carried out by placing a single loose ligature around the right sciatic nerve. The acetone test was used to evaluate the cold allodynia in CCI or Sham (without ligature) rats. The MCS (M1) was performed at low-frequency (20 μA, 100 Hz) during 15 s by deep brain stimulation (DBS-Thomas Recording device) 21 days after CCI or Sham procedures. The cold allodynia was measured before and immediately after the neurostimulation of M1 in the following time-window: 0, 15 and 30 min after MCS. Results: Cold allodynia threshold increased in animals with chronic neuropathic pain submitted to the acetone test 21 days after the CCI surgery. The M1-stimulation by DBS procedure decreased the cold allodynia immediately and until 30 min after M1-stimulation in rats with chronic neuropathic pain. Conclusion: The current proposal for a CCI model by a single loose ligature of the sciatic nerve can be employed as an experimental model of chronic neuropathic pain in rats submitted to peripheral nervous system injury. The M1-stimulation produced antinociception in rats with chronic neuropathic pain. Thus, we reinforced that the MCS decreases cold allodynia in laboratory animals submitted to persistent sciatic nerve constriction and can be a more reasonable procedure for the treatment of chronic intractable neuropathic pain.
文摘Dear Editor,The importance of the medial entorhinal cortex(MEC)for memory and spatial navigation has been shown repeatedly in many species,including mice and humans[1,2].It is,therefore,not surprising that the connectivity of this structure has been studied extensively over the past century,mainly using a range of anterograde and retrograde anatomical tracers[3].
文摘The dorsal area of the anterior cingulate cortex (ACC) constructs the salience network associated with the anterior insular cortex. Conventional brain imaging studies, such as functional magnetic resonance imaging (fMRI), have demonstrated that relational memory formation occurs in the ACC. However, how such memory is encoded and retrieved remains unknown due to limited time resolution of conventional fMRI. This study aimed to investigate temporal dynamics of the dorsal ACC (dACC) during word-pair tasks based on a newly developed event-related deep brain activity (ER-DBA) method using occipital electroencephalogram (EEG) signal powers. The method assesses dACC activity at a temporal resolution of approximately 0.3 s beyond the conventional resolution limit. We found that transient deactivation of dACC during the presentation of the second word of each pair was essential for encoding success regardless of whether the words were related or unrelated. We also found that memory accuracy was not affected by the intervention of inter-trials until the recall trial. Taken together, these findings suggest that dACC deactivation for encoding success is accompanied with short-term potentiation essential for durability of memory. We further found that false memory formation associated with the presentation of word pairs was occasionally committed. In such cases, dACC exhibited a similar transient deactivation although false memory commission was independent of related or unrelated conditions. Our findings suggest that encoding and retrieval of associates are paralleled and that simultaneous production of associates seems to be an essential strategy for successful relational memory formation. The study was limited to the assessment of dACC activity and did not account for other regional brain activities or receptor regulation related to short-term potentiation. We detected fast behavior of dACC during relational memory formation using the novel ER-DBA method. Such temporal dynamics will be important for eliciting underlying mechanisms of memory dysfunctions.
基金supported by grants from the National Natural Science Foundation of China (31671091 and 81771197)the Natural Science Foundation of Jiangsu Province, China (BK20171255)the Science and Technology Planning Project of Nantong Municipality, China (MS12017023-9)
文摘Pain consists of sensory-discriminative and emotional-affective components.The anterior cingulate cortex(ACC)is a critical brain area in mediating the affective pain.However,the molecular mechanisms involved remain largely unknown.Our recent study indicated that C-X-C motif chemokine 13(CXCL13)and its sole receptor CXCR5 are involved in sensory sensitization in the spinal cord after spinal nerve ligation(SNL).Whether CXCL13/CXCR5 signaling in the ACC contributes to the pathogenesis of pain-related aversion remains unknown.Here,we showed that SNL increased the CXCL13 level and CXCR5 expression in the ACC after SNL.Knockdown of CXCR5 by microinjection of Cxcr5 shRNA into the ACC did not affect SNL-induced mechanical allodynia but effectively alleviated neuropathic painrelated place avoidance behavior.Furthermore,electrophysiological recording from layer Ⅱ-Ⅲ neurons in the ACC showed that SNL increased the frequency and amplitude of spontaneous excitatory postsynaptic currents(sEPSCs),decreased the EPSC paired-pulse ratio,and increased the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor/N-methyl-D-aspartate receptor ratio,indicating enhanced glutamatergic synaptic transmission.Finally,superfusion of CXCL13 onto ACC slices increased the frequency and amplitude of spontaneous EPSCs.Pre-injection of Cxcr5 shRNA into the ACC reduced the increase in glutamatergic synaptic transmis sion induced by SNL.Collectively,these results suggest that CXCL13/CXCR5 signaling in the ACC is involved in neuropathic pain-related aversion via synaptic potentiation.
基金supported by the Natural Science Foundation of China,No.81260295the Graduate Student Innovation Fund of Jiangxi Province of China,No.YC2015-S090
文摘Orexins, produced in the lateral hypothalamus, are important neuropeptides that participate in the sleep/wake cycle, and their expres- sion coincides with the projection area of the vagus nerve in the brain. Vagus nerve stimulation has been shown to decrease the amounts of daytime sleep and rapid eye movement in epilepsy patients with traumatic brain injury. In the present study, we investigated whether vagus nerve stimulation promotes wakefulness and affects orexin expression. A rat model of traumatic brain injury was established using the free fall drop method. In the stimulated group, rats with traumatic brain injury received vagus nerve stimulation （frequency, 30 Hz, current, 1.0 mA; pulse width, 0.5 ms; total stimulation time, 15 minutes）. In the antagonist group, rats with traumatic brain injury were intracerebroventricularly injected with the orexin receptor type 1 （OXIR） antagonist SB334867 and received vagus nerve stimulation. Changes in consciousness were observed after stimulation in each group. Enzyme-linked immunosorbent assay, western blot assay and immunohistochemistry were used to assess the levels of orexin-A and OX1R expression in the prefrontal cortex. In the stimulated group, consciousness was substantially improved, orexin-A protein expression gradually increased within 24 hours after injury and OX1R expres- sion reached a peak at 12 hours, compared with rats subjected to traumatic brain injury only. In the antagonist group, the wake-promoting effect of vagus nerve stimulation was diminished, and orexin-A and OX1R expression were decreased, compared with that of the stim- ulated group. Taken together, our findings suggest that vagus nerve stimulation promotes the recovery of consciousness in comatose rats after traumatic brain injury. The upregulation of orexin-A and OXIR expression in the prefrontal cortex might be involved in the wake-promoting effects of vagus nerve stimulation.
基金This project is supported by National Natural Science Fundation of China
文摘The effects of electrical stimulation of second somatosensory area(S Ⅱ)andelectroacupuncture(EA)at Huantiao(GB 30)and Yanglinquan(GB 34)points on nociceptive re-sponses of neurons in the nucleus centrum medianum(CM)in the thalamus were respectively ob-served after topical application of bicuculline(Bic)at the motor cortex(MCtx),and the results werecompared with those obtained in the saline control group.It was found that following application ofBic either electrical stimulation of SII(n=11)or EA(n=11)yielded obvious inhibition on nocicep-tive responses of CM neurons(P【0.05),which was similar to the inhibitory effects obtained in thesaline control groups(n=11,n=10).After GABA application at MCtx electrical stimulation of SIIfailed to show inhibition on nociceptive responses in 3 CM neurons.It is indicated that GABA in MC-tx is involved in SII originating corticofugal regulation of nucleus CM in acupuncture analgesia.
基金the National Natural Science Foundation of China,No.30900773the Natural Science Foundation of Hunan Province in China,No.11JJ2020Young Teachers Training Program of University of Hunan Province
文摘Previous studies have demonstrated that doublecortin-positive immature neurons exist pre- dominantly in the superficial layer of the cerebral cortex of adult mammals such as guinea pigs, and these neurons exhibit very weak properties of self-proliferation during adulthood under physiological conditions. To verify whether environmental enrichment has an impact on the proliferation and maturation of these immature neurons in the prefrontal cortex of adult guinea pigs, healthy adult guinea pigs were subjected to short-term environmental enrichment. Animals were allowed to play with various cognitive and physical stimulating objects over a period of 2 weeks, twice per day, for 60 minutes each. Immunofluorescence staining results indicated that the number of doublecortin-positive cells in layer II of the prefrontal cortex was significantly increased after short-term environmental enrichment exposure. In addition, these doublecortin-positive cells co-expressed 5-bromo-2-deoxyuridine （a marker of cell prolifera- tion）, c-Fos （a marker of cell viability） and NeuN （a marker of mature neurons）. Experimental findings showed that short-term environmental enrichment can induce proliferation, activation and maturation of doublecortin-positive cells in layer II of the prefrontal cortex of adult guinea pigs.
基金supported by National Science Foundation of China (Grant 30600125)National Science Foundation Hebei Province (Grant C2011206036)
文摘The development and plasticity of central auditory system can be influenced by the change of peripheral neuronal activity. However, the molecular mechanism participating in the process remains elusive. Brain-derived neurotrophic factor(BDNF) binding with its functional receptor tropomyosin receptor kinase B(TrkB) has multiple effects on neurons. Here we used a rat model of auditory deprivation by bilateral cochlear ablation, to investigate the changes in expression of BDNF and Trk B in the auditory cortex after auditory deprivation that occurred during the critical period for the development of central auditory system. Reverse transcription-quantitative polymerase chain reaction(RTqPCR) and immunohistochemistry methods were adopted to detect the m RNA and protein expression levels of BDNF and TrkB in the auditory cortex at 2, 4, 6 and 8 weeks after surgery, respectively. The change in the expression of BDNF and TrkB mRNAs and proteins followed similar trend. In the bilateral cochlear ablation groups, the BDNF-TrkB expression level initially decreased at 2 weeks but increased at 4 weeks followed by the reduction at 6 and 8 weeks after cochlear removal, as compared to the age-matched sham control groups. In conclusion, the BDNF-TrkB signaling is involved in the plasticity of auditory cortex in an activity-dependent manner.
文摘To understand the connectivity of cerebral cor-tex, especially the spatial and temporal pattern of movement, functional magnetic resonance imaging (fMRI) during subjects performing finger key presses was used to extract functional networks and then investigated their character-istics. Motor cortex networks were constructed with activation areas obtained with statistical analysis as vertexes and correlation coefficients of fMRI time series as linking strength. The equivalent non-motor cortex networks were constructed with certain distance rules. The graphic and dynamical measures of motor cor-tex networks and non-motor cortex networks were calculated, which shows the motor cortex networks are more compact, having higher sta-tistical independence and integration than the non-motor cortex networks. It indicates the motor cortex networks are more appropriate for information diffusion.
