OBJECTIVE:To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury(CIRI)and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4(NCOA4)mediated ferritino...OBJECTIVE:To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury(CIRI)and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4(NCOA4)mediated ferritinophagy.METHODS:Sprague-Dawley male rats were divided into four groups:the sham group,model group,acupuncture group,and sham acupuncture group.After 2 h of middle cerebral artery occlusion(MCAO),reperfusion was performed for 24 h to induce CIRI.The rats were treated with acupuncture at the Neiguan(PC6)and Shuigou(GV26)acupoints.Their neurological function was evaluated by taking their Bederson scores at 2 h after ischaemia and 24 h after reperfusion.Triphenyltetrazolium chloride staining was applied to assess the cerebral infarct volume at 24 h after reperfusion.The malondialdehyde(MDA)and ferrous iron(Fe^(2+))levels were observed after 24 h of reperfusion using an assay kit.Western blotting was performed to detect the expression of NCOA4 and ferritin heavy chain 1(FTH1)at 24 h after reperfusion.Moreover,the colocalization of ferritin with neurons,NCOA4 with microtubule-associated protein 1 light chain 3(LC3),and NCOA4 with ferritin was visualized using immunofluorescence staining.RESULTS:Acupuncture significantly improved neurological function and decreased cerebral infarct volume in the acupuncture group.Following CIRI,the expression of NCOA4,LC3 and FTH1 was increased,which enhanced ferritinophagy and induced an inappropriate accumulation of Fe^(2+)and MDA in the ischaemic brain.However,acupuncture dramatically downregulated the expression of NCOA4,LC3 and FTH1,inhibited the overactivation of ferritinophagy,and decreased the levels of MDA and Fe^(2+).CONCLUSIONS:Acupuncture can inhibit NCOA4-mediated ferritinophagy and protect neurons against CIRI in a rat model.展开更多
The CREB-regulated transcriptional co-activators(CRTCs),including CRTC1,CRTC2 and CRTC3,enhance transcription of CREB-targeted genes.In addition to regulating host gene expression in response to cAMP,CRTCs also increa...The CREB-regulated transcriptional co-activators(CRTCs),including CRTC1,CRTC2 and CRTC3,enhance transcription of CREB-targeted genes.In addition to regulating host gene expression in response to cAMP,CRTCs also increase the infection of several viruses.While human immunodeficiency virus type 1(HIV-1)long terminal repeat(LTR)promoter harbors a cAMP response element and activation of the cAMP pathway promotes HIV-1 transcription,it remains unknown whether CRTCs have any effect on HIV-1 transcription and HIV-1 infection.Here,we reported that CRTC2 expression was induced by HIV-1 infection,but CRTC2 suppressed HIV-1 infection and diminished viral RNA expression.Mechanistic studies revealed that CRTC2 inhibited transcription from HIV-1 LTR and diminished RNA PolⅡoccupancy at the LTR independent of its association with CREB.Importantly,CRTC2 inhibits the activation of latent HIV-1.Together,these data suggest that in response to HIV-1 infection,cells increase the expression of CRTC2 which inhibits HIV-1 gene expression and may play a role in driving HIV-1 into latency.展开更多
The biological effects of thyroid hormone (T3) are mediated by the thyroid hormone receptor (TR). Amphibian metamorphosis is one of the most dramatic processes that are dependent on T3. T3 regulates a series of orches...The biological effects of thyroid hormone (T3) are mediated by the thyroid hormone receptor (TR). Amphibian metamorphosis is one of the most dramatic processes that are dependent on T3. T3 regulates a series of orchestrated developmental changes, which ultimately result in the conversion of an aquatic herbivorous tadpole to a terrestrial carnivorous frog. T3 is presumed to bind to TRs, which in turn recruit coactivators, leading to gene activation. The best-studied coactivators belong to the p160 or SRC family. Members of this family include SRC1/NCoA-1, SRC2/TIF2/GRIP1, and SRC3/pCIP/ACTR/AIB-1/RAC-3/TRAM-1. These SRCs interact directly with liganded TR and function as adapter molecules to recruit other coactivators such as p300/CBP. Here, we studied the expression patterns of these coactivators during various stages of development. Amongst the coactivators cloned in Xenopus laevis, SRC3 was found to be dramatically upregulated during natural and T3-induced metamorphosis, and SRC2 and p300 are expressed throughout postembryonic development with little change in their expression levels. These results support the view that these coactivators participate in gene regulation by TR during metamorphosis.展开更多
Hepatitis C virus(HCV)is still one of the main causes of liver disease worldwide.Metabolic disorders,including nonalcoholic fatty liver disease(NAFLD),induced by HCV have been shown to accelerate the progression of fi...Hepatitis C virus(HCV)is still one of the main causes of liver disease worldwide.Metabolic disorders,including nonalcoholic fatty liver disease(NAFLD),induced by HCV have been shown to accelerate the progression of fibrosis to cirrhosis and to increase the risk of hepatocellular carcinoma.An optimal peroxisome proliferator-activated receptor gamma coactivator 1-alpha(PPARGC1A)activity is crucial to prevent NAFLD installation.The present study aims to investigate the associations between two common PPARGC1A polymorphisms(rs8192678 and rs12640088)and the outcomes of HCV infection in a North African context.A series of 592 consecutive Moroccan subjects,including 292 patients with chronic hepatitis C(CHC),100 resolvers and 200 healthy controls were genotyped using a TaqMan allelic discrimination assay.PPARGC1A variations at rs8192678 and rs12640088 were not associated with spontaneous clearance of HCV infection(adjusted ORs=0.76 and 0.79 respectively,P[0.05,for both).Furthermore,multivariable logistic regression analysis showed that both SNPs were not associated with fibrosis progression(OR=0.71;95%CI 0.20–2.49;P=0.739;OR=1.28;95%CI 0.25–6.54;P=0.512,respectively).We conclude that,in the genetic context of South Mediterranean patients,rs8192678 and rs12640088 polymorphisms of PPARGC1 A are neither associated with spontaneous clearance nor with disease progression in individuals infected with HCV.展开更多
Since we had previously demonstrated that siRNAs to tristetraprolin (TTP) markedly inhibited insulin stimulation of hepatic HMG-CoA reductase (HMGR) transcription, we investigated the effects of transfecting rat liver...Since we had previously demonstrated that siRNAs to tristetraprolin (TTP) markedly inhibited insulin stimulation of hepatic HMG-CoA reductase (HMGR) transcription, we investigated the effects of transfecting rat liver with TTP constructs. We found that transfecting diabetic rats with TTP did not increase HMGR transcription but rather led to modest inhibition. We then investigated whether co-transfection with protein kinase B, hepatic form (AKT2), might lead to phosphorylation and result in activation of HMGR transcription. We found that this treatment resulted in near complete inhibition of transcription. Transfection with peroxisome proliferator-activated receptor g coactivator (PGC-1a) also inhibited HMGR transcription. These results show that although TTP is needed for activation of HMGR transcription, it cannot by itself activate this process. AKT2 and PGC-1a, which mediate the activation of gluconeogenic genes by insulin, exert the opposite effect on HMGR.展开更多
Transcriptional coactivators regulate the rate of gene expression in the nucleus.Nuclear receptor coactivator 6(NCOA6),a coactivator,has been implicated in embryonic development,metabolism,and cancer pathogenesis,but ...Transcriptional coactivators regulate the rate of gene expression in the nucleus.Nuclear receptor coactivator 6(NCOA6),a coactivator,has been implicated in embryonic development,metabolism,and cancer pathogenesis,but its role in innate immunity and inflammatory diseases remains unclear.Here,we demonstrated that NCOA6 was expressed in monocytes and macrophages and that its level was increased under proinflammatory conditions.Unexpectedly,nuclear NCOA6 was found to translocate to the cytoplasm in activated monocytes and then become incorporated into the inflammasome with NLRP3 and ASC,forming cytoplasmic specks.Mechanistically,NCOA6 associated with the ATP hydrolysis motifs in the NACHT domain of NLRP3,promoting the oligomerization of NLRP3 and ASC and thereby instigating the production of IL-1βand active caspase-1.Of note,Ncoa6 deficiency markedly inhibited NLRP3 hyperactivation caused by the Nlrp3^(R258W) gain-of-function mutation in macrophages.Genetic ablation of Ncoa6 substantially attenuated the severity of two NLRP3-dependent diseases,folic-induced acute tubular necrosis and crystal-induced arthritis,in mice.Consistent with these findings,NCOA6 was highly expressed in macrophages derived from gout patients,and NCOA6-positive macrophages were significantly enriched in gout macrophages according to the transcriptome profiling results.Conclusively,NCOA6 is a critical regulator of NLRP3 inflammasome activation and is therefore a promising target for NLRP3-dependent diseases,including gout.展开更多
Transcriptional dysregulation of genes is a hallmark of tumors and can serve as targets for cancer drug development.However,it is extremely challenging to develop small-molecule inhibitors to target abnormally express...Transcriptional dysregulation of genes is a hallmark of tumors and can serve as targets for cancer drug development.However,it is extremely challenging to develop small-molecule inhibitors to target abnormally expressed transcription factors(TFs)except for the nuclear receptor family of TFs.Little is known about the interaction between TFs and transcription cofactors in gastroesophageal adenocarcinoma(GEA)or the therapeutic effects of targeting TF and transcription cofactor complexes.In this study,we found that ETS homologous factor(EHF)expression is promoted by a core transcriptional regulatory circuitry(CRC),specifically ELF3-KLF5-GATA6,and interference with its expression suppressed the malignant biological behavior of GEA cells.Importantly,we identified Ajuba LIM protein(AJUBA)as a new coactivator of EHF that cooperatively orchestrates transcriptional network activity in GEA.Furthermore,we identified KRAS signaling as a common pathway downstream of EHF and AJUBA.Applicably,dual targeting of EHF and AJUBA by lipid nanoparticles cooperatively attenuated the malignant biological behaviors of GEA in vitro and in vivo.In conclusion,EHF is upregulated by the CRC and promotes GEA malignancy by interacting with AJUBA through the KRAS pathway.Targeting of both EHF and its coactivator AJUBA through lipid nanoparticles is a novel potential therapeutic strategy.展开更多
OBJECTIVE:To explore the potential molecular mechanism of Qigu capsule(芪骨胶囊,QGC)improve the functional performance of skeletal muscle.METHODS:The primary components of QGC were analyzed using high-performance liqu...OBJECTIVE:To explore the potential molecular mechanism of Qigu capsule(芪骨胶囊,QGC)improve the functional performance of skeletal muscle.METHODS:The primary components of QGC were analyzed using high-performance liquid chromatography(HPLC).Muscle dysfunction was established in male C57BL/6 mice treated with dexamethasone(1 mg/kg body weight,i.p.,six weeks).Rotarod test,mitochondrial ultrastructure,respiratory chain complex V activity,succinate dehydrogenase(SDH)activity,adenosine triphosphate(ATP)content,and reactive oxygen species(ROS)levels were assessed.The mitochondrial biogenesis-related protein expressions were analyzed using Western blot or polymerase chain reaction(PCR).RESULTS:QGC treatment enhanced Rotarod test performance.Additionally,QGC significantly alleviated dexamethasone-induced mitochondrial damage,reduced mitochondrial swelling,increased respiratory chain complex enzyme activity,SDH activity,ATP content,and decreased ROS levels.PCR and western blot results revealed that QGC enhanced mitochondrial biogenesis via adenosine 5'-monophosphate-activated protein kinase(AMPK)/peroxisome proliferator-activated receptor-γcoactivator 1-alpha(PGC-1α)signaling pathway.CONCLUSIONS:QGC ameliorates dexamethasoneinduced skeletal muscle dysfunction by activating AMPK/PGC-1α,which might be developed as a therapeutic agent for treating age-related muscle weakness.展开更多
Virus-encoding RNA-dependent RNA polymerase(RdRp)is essential for genome replication and gene transcription of human coronaviruses(HCoVs),including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).We previo...Virus-encoding RNA-dependent RNA polymerase(RdRp)is essential for genome replication and gene transcription of human coronaviruses(HCoVs),including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).We previously identified the interaction between the catalytic subunit NSP12 of SARS-CoV-2 RdRp and the host protein CREB-regulated transcription coactivator 3(CRTC3),a member of the CRTC family that regulates cyclic AMP response element-binding protein(CREB)-mediated transcriptional activation.Currently,the implication of CRTC3 in the pathogenesis of HCoVs is poorly understood.Herein,we demonstrated that CRTC3 attenuates RdRp activity and SARS-CoV-2 genome replication,therefore reducing the production of progeny viruses.The interaction of CRTC3 with NSP12 contributes to its inhibitory effect on RdRp activity.Furthermore,we expanded the suppressive effects of two other CRTC family members(CRTC1 and CRTC2)on the RdRp activities of lethal HCoVs,including SARS-CoV-2 and Middle East respiratory syndrome coronavirus(MERS-CoV),along with the CREB antagonization.Overall,our research suggests that CRTCs restrict the replication of HCoVs and are antagonized by CREB,which not only provides new insights into the replication regulation of HCoVs,but also offers important information for the development of anti-HCoV interventions.展开更多
Background Some single nucleotide polymorphisms （SNPs） in the peroxisome proliferator-activated receptor-y coactivator （PGC）-1α gene have been reported to be associated with type 2 diabetes in different populatio...Background Some single nucleotide polymorphisms （SNPs） in the peroxisome proliferator-activated receptor-y coactivator （PGC）-1α gene have been reported to be associated with type 2 diabetes in different populations, and studies on Chinese patients yielded controversial results. The objective of this case-control study was to explore the relationship between SNPs of PGC-1α and type 2 diabetes in the southern Chinese population and to determine whether the common variants： Gly482Ser and Thr394Thr, in the PGC-1α gene have any impacts on interaction with myocyte enhancer factor （MEF） 2C. Methods The SNPs in all exons of the PGC-1α gene was investigated in 50 type 2 diabetic patients using polymerase chain reaction-single strand conformational polymorphism （PCR-SSCP） and direct sequencing. Thereafter, 263 type 2 diabetic patients and 282 healthy controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP）. A bacterial two-hybrid system and site-directed mutagenesis were used to investigate whether Gly482Ser and Thr394Thr variants in the PGC-1α gene alter the interaction with MEF2C. Results Three frequent SNPs （Thr394Thr, Gly482Ser and Thr528Thr） were found in exons of the PGC-1α gene. Only the Gly482Ser variant had a different distribution between diabetic patients and healthy subjects, with the 482Ser allele more frequent in patients than in controls （40.1% vs 29.3%, P〈0.01）. Even in controls, the 482Ser（A） carriers were more likely to have higher levels of total cholesterol and low-density lipoprotein cholesterol than the 482Gly（G） carriers. The 394A-482G-528A haplotype was associated with protection from diabetes, while the 394A-482A-528A was associated with the susceptibility to diabetes. The bacterial two-hybrid system and site-directed mutagenesis revealed that the 482Ser variant was less efficient than the 482Gly variant to interact with MEF2C, whereas the 394Thr （A） had a synergic effect on the interaction between 482Ser variant and MEF2C. Conclusions The results suggested that the 482Ser variant of PGC-1α conferred the susceptibility to type 2 diabetes in the southern Chinese population. The underlying mechanism may be attributable, at least in part, to the altered interaction between the different variants （Gly482Ser, Thr394Thr） in the PGC-1α gene and MEF2C.展开更多
The GATA family consists of six members, GATA 1-6. In this study, we focused on GATA-2, which is expressed predominantly in hematopoietic progenitor cells and plays the key role in keeping these cells in the undiffere...The GATA family consists of six members, GATA 1-6. In this study, we focused on GATA-2, which is expressed predominantly in hematopoietic progenitor cells and plays the key role in keeping these cells in the undifferentiated status. CREB-binding proteins (CBP) are essential transcriptional coacti- vators for a large number of regulated DNA-binding transcription factors, including GATA-1. But there have been no reports on whether CBP is still a co-activator of GATA-2. Here, we used the immunopre- cipitation and pull-down experiments to show that the GATA-2 and CBP were physically binding to- gether, and clarified the binding sites CH1, CH3 , CH452 and CT1430 in CBP and N-finger, C-finger and N-C-finger in GATA-2. Luciferase assay results in our experiment indicated that CBP could increase GATA-2 transcriptional activity in the dose-dependent manner. GATA-1 is mainly expressed in differen- tiated hematopoietic cells, but still has overlap expression with GATA-2. CBP is a coactivator of GATA-2 and GATA-1. The investigation on the mechanism that could decide whether CBP binds to GATA-2 to keep hematopoietic cells in the progenitor status or to GATA-1 to start differentiation will be a very in- teresting and very meaningful project in the near future.展开更多
Activated G-protein-coupled receptor 39(GPR39)has been shown to attenuate inflammation by interacting with sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α).However,whether GPR3...Activated G-protein-coupled receptor 39(GPR39)has been shown to attenuate inflammation by interacting with sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α).However,whether GPR39 attenuates neuropathic pain remains unclear.In this study,we established a Sprague-Dawley rat model of spared nerve injury-induced neuropathic pain and found that GPR39 expression was significantly decreased in neurons and microglia in the spinal dorsal horn compared with sham-operated rats.Intrathecal injection of TC-G 1008,a specific agonist of GPR39,significantly alleviated mechanical allodynia in the rats with spared nerve injury,improved spinal cord mitochondrial biogenesis,and alleviated neuroinflammation.These changes were abolished by GPR39 small interfering RNA(siRNA),Ex-527(SIRT1 inhibitor),and PGC-1αsiRNA.Taken together,these findings show that GPR39 activation ameliorates mechanical allodynia by activating the SIRT1/PGC-1αpathway in rats with spared nerve injury.展开更多
In mammals,the timing of physiological,biochemical and behavioral processes over a 24-h period is controlled by circadian rhythms.To entrain the master clock located in the suprachiasmatic nucleus of the hypothalamus ...In mammals,the timing of physiological,biochemical and behavioral processes over a 24-h period is controlled by circadian rhythms.To entrain the master clock located in the suprachiasmatic nucleus of the hypothalamus to a precise 24-h rhythm,environmental zeitgebers are used by the circadian system.This is done primarily by signals from the retina via the retinohypothalamic tract,but other cues like exercise,feeding,temperature,anxiety,and social events have also been shown to act as non-photic zeitgebers.The recently identified myokine irisin is proposed to serve as an entraining non-photic signal of exercise.Irisin is a product of cleavage and modification from its precursor membrane fibronectin typeⅢdomain-containing protein 5(FNDC5)in response to exercise.Apart from well-known peripheral effects,such as inducing the"browning"of white adipocytes,irisin can penetrate the blood-brain barrier and display the effects on the brain.Experimental data suggest that FNDC5/irisin mediates the positive effects of physical activity on brain functions.In several brain areas,irisin induces the production of brain-derived neurotrophic factor(BDNF).In the master clock,a significant role in gating photic stimuli in the retinohypothalamic synapse for BDNF is suggested.However,the brain receptor for irisin remains unknown.In the current review,the interactions of physical activity and the irisin/BDNF axis with the circadian system are reconceptualized.展开更多
Recent studies have identified mutations in PHF8, an X-linked gene encoding a JmjC domain-containing protein, as a causal factor for X-linked mental retardation （XLMR） and cleft lip/cleft palate. However, the underl...Recent studies have identified mutations in PHF8, an X-linked gene encoding a JmjC domain-containing protein, as a causal factor for X-linked mental retardation （XLMR） and cleft lip/cleft palate. However, the underlying mechanism is unknown. Here we show that PHF8 is a histone demethylase and coactivator for retinoic acid receptor （RAR）. Although activities for both H3K4me3/2/1 and H3K9me2/1 demethylation were detected in cellularbased assays, reeombinant PHF8 exhibited only H3K9me2/1 demethylase activity in vitro, suggesting that PHF8 is an H3K9me2/1 demethylase whose specificity may be modulated in vivo. Importantly, a mutant PHF8 （phenylalanine at position 279 to serine） identified in the XLMR patients is defective in enzymatie activity, indicating that the loss of histone demethylase activity is causally linked with the onset of disease. In addition, we show that PHF8 binds specifically to H3K4me3/2 peptides via an N-terminal PHD finger domain. Consistent with a role for PHF8 in neuronal differentiation, knockdown of PHF8 in mouse embryonic carcinoma P19 cells impairs RA-induced neuronal differentiation, whereas overexpression of the wild-type but not the F279S mutant PHF8 drives PI9 cells toward neuronal differentiation. Furthermore, we show that PHF8 interacts with RAR~ and functions as a coactivator for RARa. Taken together, our results suggest that histone methylation modulated by PHF8 plays a critical role in neuronal differentiation.展开更多
MicroRNA-124 contributes to neurogenesis through regulating its targets, but its expression both in the brain of Huntington＇s disease mouse models and patients is decreased. However, the effects of microRNA-124 on th...MicroRNA-124 contributes to neurogenesis through regulating its targets, but its expression both in the brain of Huntington＇s disease mouse models and patients is decreased. However, the effects of microRNA-124 on the progression of Huntington＇s disease have not been reported. Results from this study showed that microRNA-124 increased the latency to fall for each R6/2 Hunting- ton＇s disease transgenic mouse in the rotarod test. 5-Bromo-2＇-deoxyuridine （BrdU） staining of the striatum shows an increase in neurogenesis. In addition, brain-derived neurotrophic factor and peroxisome proliferator-activated receptor gamma coactivator 1-alpha protein levels in the striatum were increased and SRY-related HMG box transcription factor 9 protein level was de- creased. These findings suggest that microRNA-124 slows down the progression of Huntington＇s disease possibly through its important role in neuronal differentiation and survival.展开更多
OBJECTIVE: To investigate whether peroxisome proliferator-activated receptor γ-coactivator-1α/nuclear respiratory factor 1(PGC-1α/NRF1) activity can protect mitochondrial function in the setting of cardiac hypertro...OBJECTIVE: To investigate whether peroxisome proliferator-activated receptor γ-coactivator-1α/nuclear respiratory factor 1(PGC-1α/NRF1) activity can protect mitochondrial function in the setting of cardiac hypertrophy and improve cardiomyocyte energy metabolism. METHODS: Cardiac hypertrophy was modeled in H9c2 cells treated with isoproterenol(ISO) to assess the effects of Shenge San( 参 蛤 散, SGS) on cell viability and mitochondrial membrane potential. We assessed mitochondrial complex m RNA levels and mitochondrial oxidative phosphorylation factor m RNA and protein levels. RESULTS: Compared with the 100 μM ISO group, cell size was significantly decreased in the 0.3 mg/m L SGS and 20 μM ZLN005(PGC-1α activator) groups(P < 0.01). Compared with the SGS(0.3) +ISO group, we observed lower phosphorylated adenosine monophosphateactivated kinase(AMPK) protein levels in the ISO and ZLN005+SGS+ISO groups(P < 0.01). Compared with the compound C group, SGS significantly increased PGC-1α expression in ISO-induced cardiac hypertrophy cells(P < 0.01), and this was inhibited by compound C pretreatment(P < 0.05). Compared with the ISO group, the mitochondrial red-green fluorescence ratio increased in the 0.3 mg/m L SGS group(P < 0.05). m RNA levels of cytochrome c oxidase subunit 1(CO1) in the ISO and compound C groups were lower than those in control group(P < 0.01), and the m RNA levels of CO1 and ATP8 were significantly lower in the ISO and compound C groups versus control(P < 0.01). Compared with the SGS(0.3) +ISO group, ATP synthetase subunit 8(ATP8) m RNA was significantly decreased in the ISO group(P < 0.01) and compound C+SGS+ISO group(P < 0.05). Compared with the SGS(0.3) +ISO group, NRF1 m RNA levels were significantly decreased(P < 0.05) in the ISO and compound C+SGS+ISO groups. CONCLUSIONS: SGS can attenuate ISO-induced cardiomyocyte hypertrophy, restore the decrease in mitochondrial membrane potential, and upregulate PGC-1α/NRF1 levels. Notably, these effects can be blocked by AMPK inhibitor-compound C.展开更多
OBJECTIVE: To evaluate the protective effects of serum containing Dangua Fang( 丹 瓜 方) on vascular endothelium damaged by oxidative stress. METHODS: Five experiments were completed in this paper. In the first experi...OBJECTIVE: To evaluate the protective effects of serum containing Dangua Fang( 丹 瓜 方) on vascular endothelium damaged by oxidative stress. METHODS: Five experiments were completed in this paper. In the first experiment, we found the most suitable serum containing Dangua Fang by comparing groups with different serum containing Dangua Fang. In the second experiments we analyzed Dangua Fang influencing endothelial cell viability and apoptosis and cell cycle. The third experiment on Dangua Fang intervention of mitochondrial respiratory chain. The fourth experiment on Dangua Fang intervention of mitochondrial membrane potential. And finally, on the fifth experiment we researched the mechanism of Dangua Fang improving mitochondrial function by comparing the Na~+-k~+-ATPase and peroxisome proliferator-activated receptor-gamma coactivator-1alpha(PGC-1α) in the Dangua group with the diazoxide group and Co Q+Vit C group. RESULTS: We compared the control group in the first experiments and the OD values in DZ1 group was the most significant in all intervening groups. The recipe of DZ1(5% serum containing Dangua Fang) was used in the following experiments. Compared with the control group, cell viability, cell cycle(G2 + S), cytochrome c oxidase(COX), R3 red/green, R2 red/green, R1 red/green decreased and apoptosis, succinate dehydrogenase(SDH), green(R2 + R3), Na+-k+-ATPase, PGC-1α increased in the model group. Compared with the model group, cell viability, G2+S, COX, R3 red/green, R2 red/green, R1 red/green raised and apoptosis, green(R2 + R3), Na-K-ATPase decreased in the Dangua group;G2 + S, R3 red/green, R2 red/green, R1 red/green raised and green(R2 + R3) decreased in the Co Q + Vit C group. Na-K-ATPase increased in the combined group(P < 0.05 or < 0.01). CONCLUSIONS: Dangua Fang protects oxidative stressinduced endothelial cells damaged by promotion of mitochondrial biogenesis, reduction of Na~+-K~+-ATPase activity and regulation of mitochondrial respiratory chain function restoring mitochondrial membrane potential.展开更多
Ferroptosis is a regulated form of cell death which is considered an oxidative iron-dependent process.The lipid hydroperoxidase glutathione peroxidase 4 prevents the iron(Fe2+)-dependent formation of toxic lipid react...Ferroptosis is a regulated form of cell death which is considered an oxidative iron-dependent process.The lipid hydroperoxidase glutathione peroxidase 4 prevents the iron(Fe2+)-dependent formation of toxic lipid reactive oxygen species.While emerging evidence indicates that inhibition of glutathione peroxidase 4 as a hallmark of ferroptosis in many cancer cell lines,the involvement of this biochemical pathway in neuronal death remains largely unclear.Here,we investigate,first whether the ferroptosis key players are involved in the neuronal cell death induced by erastin.The second objective was to examine whether there is a cross talk between ferroptosis and autophagy.The third main was to address neuron response to erastin,with a special focus on ferritin and nuclear receptor coactivator 4-mediated ferritinophagy.To test this in neurons,erastin(0.5-8μM)was applied to hippocampal HT22 neurons for 16 hours.In addition,cells were cultured with the autophagy inhibitor,3-methyladenin(10 mM)and/or ferroptosis inhibitors,ferrostatin 1(10-20μM)or deferoxamine(10-200μM)before exposure to erastin.In this study,we demonstrated by immunofluorescence and western blot analysis,that erastin downregulates dramatically the expression of glutathione peroxidase 4,the sodium-independent cystine-glutamate antiporter and nuclear receptor coactivator 4.The protein levels of ferritin and mitochondrial ferritin in HT22 hippocampal neurons did not remarkably change following erastin treatment.In addition,we demonstrated that not only the ferroptosis inhibitor,ferrostatin1/deferoxamine abrogated the ferroptotic cell death induced by erastin in hippocampal HT22 neurons,but also the potent autophagy inhibitor,3-methyladenin.We conclude that(1)erastin-induced ferroptosis in hippocampal HT22 neurons,despite reduced nuclear receptor coactivator 4 levels,(2)that either nuclear receptor coactivator 4-mediated ferritinophagy does not occur or is of secondary importance in this model,(3)that ferroptosis seems to share some features of the autophagic cell death process.展开更多
In the past,contraction-induced production of reactive oxygen species(ROS)has been implicated in oxidative stress to skeletal muscle.As research advances,clear evidence has revealed a more complete role of ROS under b...In the past,contraction-induced production of reactive oxygen species(ROS)has been implicated in oxidative stress to skeletal muscle.As research advances,clear evidence has revealed a more complete role of ROS under both physiologic and pathologic conditions.Central to the role of ROS is the redox signaling pathways that control exercise-induced major physiologic and cellular responses and adaptations,such as mitochondrial biogenesis,mitophagy,mitochondrial morphologic dynamics,antioxidant defense,and inflammation.The current review focuses on how muscle contraction and immobilization may activate or inhibit redox signalings and their impact on muscle mitochondrial homeostasis and physiologic implications.展开更多
OBJECTIVE:To explore whether kidney Yang deficiency(KYD)is prone to metabolic disorders may be linked to impaired mitochondrial function in thermogenesis and metabolic tissues.METHODS:A rat model of KYD was used,which...OBJECTIVE:To explore whether kidney Yang deficiency(KYD)is prone to metabolic disorders may be linked to impaired mitochondrial function in thermogenesis and metabolic tissues.METHODS:A rat model of KYD was used,which was established using Sprague Dawley rat dams with warm preference subjected to herbal treatment that can improve kidney Yang.The human relevance was confirmed by reduced serum corticosterone levels,and increased preference for warm location.RESULTS:KYD Rats were underdeveloped.Adenosinetriphosphate(ATP)production was reduced in the brown fat,but increased in the muscle.However,oxidative phosphorylated complexes to generate ATP and mitochondrial biogenesis marker were reduced in both tissues.When the second insult of high-fat diet(HFD)was introduced,KYD rats gained less weight yet developed more severe lipid and glucose metabolic disorders.This may be driven by disregulated liver gluconeogenesis marker forkhead box protein O1 and lipid metabolic regulator cholesterol 7 alpha-hydroxylase.CONCLUSION:KYD rats exhibited reduced mitochondrial function in the brown fat,but were partially compensated by skeletal muscle,associated with the phenotype of warm preference and metabolic disorder,which was further exacerbated by additional HFD consumption.Future studies can focus on treatment targetting mitochondria function to reverse this phenotype.展开更多
基金the National Natural Science Foundation of China:Mechanism of Acupuncture in Extending Thrombolytic Time Window of Cerebral Infarction Based on Nuclear Receptor Coactivator 4 Mediated Ferritinophagy(No.82205238)National Natural Science Foundation of China:Exploring the Mechanism of Acupuncture Improving Thrombolytic Safety in Cerebral Infarction through the ERK1/2-mTOR Pathway Based on Autophagy Apoptosis Interaction(No.82074525)+1 种基金Natural Science Foundation of Jiangsu Province:Experimental Study on Acupuncture Regulation of Ferroptosis-NLRP3 Inflammasome Pathway to Reduce Hemorrhagic Transformation after Thrombolysis in Cerebral Infarction(No.BK20210689)Traditional Chinese Medicine Science and Technology Development Plan Project of Jiangsu Province:Clinical and Experimental Study on Acupuncture Improving the Safety of rt-PA Intravenous Thrombolysis in Cerebral Infarction(No.YB2020005)。
文摘OBJECTIVE:To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury(CIRI)and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4(NCOA4)mediated ferritinophagy.METHODS:Sprague-Dawley male rats were divided into four groups:the sham group,model group,acupuncture group,and sham acupuncture group.After 2 h of middle cerebral artery occlusion(MCAO),reperfusion was performed for 24 h to induce CIRI.The rats were treated with acupuncture at the Neiguan(PC6)and Shuigou(GV26)acupoints.Their neurological function was evaluated by taking their Bederson scores at 2 h after ischaemia and 24 h after reperfusion.Triphenyltetrazolium chloride staining was applied to assess the cerebral infarct volume at 24 h after reperfusion.The malondialdehyde(MDA)and ferrous iron(Fe^(2+))levels were observed after 24 h of reperfusion using an assay kit.Western blotting was performed to detect the expression of NCOA4 and ferritin heavy chain 1(FTH1)at 24 h after reperfusion.Moreover,the colocalization of ferritin with neurons,NCOA4 with microtubule-associated protein 1 light chain 3(LC3),and NCOA4 with ferritin was visualized using immunofluorescence staining.RESULTS:Acupuncture significantly improved neurological function and decreased cerebral infarct volume in the acupuncture group.Following CIRI,the expression of NCOA4,LC3 and FTH1 was increased,which enhanced ferritinophagy and induced an inappropriate accumulation of Fe^(2+)and MDA in the ischaemic brain.However,acupuncture dramatically downregulated the expression of NCOA4,LC3 and FTH1,inhibited the overactivation of ferritinophagy,and decreased the levels of MDA and Fe^(2+).CONCLUSIONS:Acupuncture can inhibit NCOA4-mediated ferritinophagy and protect neurons against CIRI in a rat model.
基金We thank National Infrastructure of Microbial Resources(NIMR-2014-3)for providing valuable reagentsThis work was supported by the National Mega-Project for Infectious Disease(2018ZX10301408 SC)+4 种基金the National Key Research and Development program of China(2018YFE0107600 SC)the National Natural Science Foundation of China(81903679 LM)the National Natural Science Foundation of China(81772205 SC)Peking Union Medical College Youth Fund(332017075 LM)CAMS innovation fund for Medical Sciences(2018-I2M-3-004 SC).
文摘The CREB-regulated transcriptional co-activators(CRTCs),including CRTC1,CRTC2 and CRTC3,enhance transcription of CREB-targeted genes.In addition to regulating host gene expression in response to cAMP,CRTCs also increase the infection of several viruses.While human immunodeficiency virus type 1(HIV-1)long terminal repeat(LTR)promoter harbors a cAMP response element and activation of the cAMP pathway promotes HIV-1 transcription,it remains unknown whether CRTCs have any effect on HIV-1 transcription and HIV-1 infection.Here,we reported that CRTC2 expression was induced by HIV-1 infection,but CRTC2 suppressed HIV-1 infection and diminished viral RNA expression.Mechanistic studies revealed that CRTC2 inhibited transcription from HIV-1 LTR and diminished RNA PolⅡoccupancy at the LTR independent of its association with CREB.Importantly,CRTC2 inhibits the activation of latent HIV-1.Together,these data suggest that in response to HIV-1 infection,cells increase the expression of CRTC2 which inhibits HIV-1 gene expression and may play a role in driving HIV-1 into latency.
文摘The biological effects of thyroid hormone (T3) are mediated by the thyroid hormone receptor (TR). Amphibian metamorphosis is one of the most dramatic processes that are dependent on T3. T3 regulates a series of orchestrated developmental changes, which ultimately result in the conversion of an aquatic herbivorous tadpole to a terrestrial carnivorous frog. T3 is presumed to bind to TRs, which in turn recruit coactivators, leading to gene activation. The best-studied coactivators belong to the p160 or SRC family. Members of this family include SRC1/NCoA-1, SRC2/TIF2/GRIP1, and SRC3/pCIP/ACTR/AIB-1/RAC-3/TRAM-1. These SRCs interact directly with liganded TR and function as adapter molecules to recruit other coactivators such as p300/CBP. Here, we studied the expression patterns of these coactivators during various stages of development. Amongst the coactivators cloned in Xenopus laevis, SRC3 was found to be dramatically upregulated during natural and T3-induced metamorphosis, and SRC2 and p300 are expressed throughout postembryonic development with little change in their expression levels. These results support the view that these coactivators participate in gene regulation by TR during metamorphosis.
文摘Hepatitis C virus(HCV)is still one of the main causes of liver disease worldwide.Metabolic disorders,including nonalcoholic fatty liver disease(NAFLD),induced by HCV have been shown to accelerate the progression of fibrosis to cirrhosis and to increase the risk of hepatocellular carcinoma.An optimal peroxisome proliferator-activated receptor gamma coactivator 1-alpha(PPARGC1A)activity is crucial to prevent NAFLD installation.The present study aims to investigate the associations between two common PPARGC1A polymorphisms(rs8192678 and rs12640088)and the outcomes of HCV infection in a North African context.A series of 592 consecutive Moroccan subjects,including 292 patients with chronic hepatitis C(CHC),100 resolvers and 200 healthy controls were genotyped using a TaqMan allelic discrimination assay.PPARGC1A variations at rs8192678 and rs12640088 were not associated with spontaneous clearance of HCV infection(adjusted ORs=0.76 and 0.79 respectively,P[0.05,for both).Furthermore,multivariable logistic regression analysis showed that both SNPs were not associated with fibrosis progression(OR=0.71;95%CI 0.20–2.49;P=0.739;OR=1.28;95%CI 0.25–6.54;P=0.512,respectively).We conclude that,in the genetic context of South Mediterranean patients,rs8192678 and rs12640088 polymorphisms of PPARGC1 A are neither associated with spontaneous clearance nor with disease progression in individuals infected with HCV.
文摘Since we had previously demonstrated that siRNAs to tristetraprolin (TTP) markedly inhibited insulin stimulation of hepatic HMG-CoA reductase (HMGR) transcription, we investigated the effects of transfecting rat liver with TTP constructs. We found that transfecting diabetic rats with TTP did not increase HMGR transcription but rather led to modest inhibition. We then investigated whether co-transfection with protein kinase B, hepatic form (AKT2), might lead to phosphorylation and result in activation of HMGR transcription. We found that this treatment resulted in near complete inhibition of transcription. Transfection with peroxisome proliferator-activated receptor g coactivator (PGC-1a) also inhibited HMGR transcription. These results show that although TTP is needed for activation of HMGR transcription, it cannot by itself activate this process. AKT2 and PGC-1a, which mediate the activation of gluconeogenic genes by insulin, exert the opposite effect on HMGR.
基金supported by grants from the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(2015R1A3A2032927 and 2021R1A2C1008130).
文摘Transcriptional coactivators regulate the rate of gene expression in the nucleus.Nuclear receptor coactivator 6(NCOA6),a coactivator,has been implicated in embryonic development,metabolism,and cancer pathogenesis,but its role in innate immunity and inflammatory diseases remains unclear.Here,we demonstrated that NCOA6 was expressed in monocytes and macrophages and that its level was increased under proinflammatory conditions.Unexpectedly,nuclear NCOA6 was found to translocate to the cytoplasm in activated monocytes and then become incorporated into the inflammasome with NLRP3 and ASC,forming cytoplasmic specks.Mechanistically,NCOA6 associated with the ATP hydrolysis motifs in the NACHT domain of NLRP3,promoting the oligomerization of NLRP3 and ASC and thereby instigating the production of IL-1βand active caspase-1.Of note,Ncoa6 deficiency markedly inhibited NLRP3 hyperactivation caused by the Nlrp3^(R258W) gain-of-function mutation in macrophages.Genetic ablation of Ncoa6 substantially attenuated the severity of two NLRP3-dependent diseases,folic-induced acute tubular necrosis and crystal-induced arthritis,in mice.Consistent with these findings,NCOA6 was highly expressed in macrophages derived from gout patients,and NCOA6-positive macrophages were significantly enriched in gout macrophages according to the transcriptome profiling results.Conclusively,NCOA6 is a critical regulator of NLRP3 inflammasome activation and is therefore a promising target for NLRP3-dependent diseases,including gout.
基金This work was supported by grants from the National Key Research and Development Program of China(2021YFA0909300 to Dong Yin)the National Natural Science Foundation of China(82372617,81972658 and 81802812 to Li Peng,81803636 to Xiaoqing Yuan,82073067 and 81872140 to Dong Yin)+5 种基金Guangdong Basic and Applied Basic Research Foundation(2024B1515020090,2023A1515012683,2019A1515012114 and 2018A030313129 to Li Peng,2024A1515030038 to Xiaoqing Yuan,2021A0505030084 and 2019B020226003 to Dong Yin)Basic and Applied Basic Research of Guangzhou Municipal Basic Research Plan(2024A03J0845 and 2023A04J2098 to Li Peng)National Postdoctoral Program for Innovation Talents(grant no.BX20190395 to Li Peng)China Postdoctoral Science Foundation(grant no.2019M663254 to Li Peng)the Fundamental Research Funds for the Central Universities(grant no.20ykpy105 to Li Peng)the Science and Technology Planning Project of Guangdong Province(2023B1212060013 and 2020B1212030004).
文摘Transcriptional dysregulation of genes is a hallmark of tumors and can serve as targets for cancer drug development.However,it is extremely challenging to develop small-molecule inhibitors to target abnormally expressed transcription factors(TFs)except for the nuclear receptor family of TFs.Little is known about the interaction between TFs and transcription cofactors in gastroesophageal adenocarcinoma(GEA)or the therapeutic effects of targeting TF and transcription cofactor complexes.In this study,we found that ETS homologous factor(EHF)expression is promoted by a core transcriptional regulatory circuitry(CRC),specifically ELF3-KLF5-GATA6,and interference with its expression suppressed the malignant biological behavior of GEA cells.Importantly,we identified Ajuba LIM protein(AJUBA)as a new coactivator of EHF that cooperatively orchestrates transcriptional network activity in GEA.Furthermore,we identified KRAS signaling as a common pathway downstream of EHF and AJUBA.Applicably,dual targeting of EHF and AJUBA by lipid nanoparticles cooperatively attenuated the malignant biological behaviors of GEA in vitro and in vivo.In conclusion,EHF is upregulated by the CRC and promotes GEA malignancy by interacting with AJUBA through the KRAS pathway.Targeting of both EHF and its coactivator AJUBA through lipid nanoparticles is a novel potential therapeutic strategy.
基金Supported by Shanghai Clinical Research Center for Chronic Musculoskeletal Diseases(20MC1920600)Shanghai Key Clinical Specialty"Traditional Chinese Medicine Orthopaedic Traumatology"(shslczdzk03901)+4 种基金the Second Round of Construction Project of National TCM Academic School Inheritance Studio"Shi's Trauma Department"[Letter of the People's Education of Traditional Chinese Medicine(2019)No.62]Shanghai High-level Local Universities"Chronic Muscle and Bone Damage Research and Transformation"Innovation Team[No.3 of Shanghai Education Commission(2022)]"Extension Plan for the Inheritance of Shanghai Style Traditional Chinese Medicine Schools",Construction of TCM Specialty Alliance for Muscle and Bone Injury in East China Region and City Level"[ZY(2021-2023)-0302]Program for Shanghai High-Level Local University Innovation Team(SZY20220315)Shanghai Shenkang Hospital Development Center Clinical Three-year Action Plan(SHDC2020CR3090B)。
文摘OBJECTIVE:To explore the potential molecular mechanism of Qigu capsule(芪骨胶囊,QGC)improve the functional performance of skeletal muscle.METHODS:The primary components of QGC were analyzed using high-performance liquid chromatography(HPLC).Muscle dysfunction was established in male C57BL/6 mice treated with dexamethasone(1 mg/kg body weight,i.p.,six weeks).Rotarod test,mitochondrial ultrastructure,respiratory chain complex V activity,succinate dehydrogenase(SDH)activity,adenosine triphosphate(ATP)content,and reactive oxygen species(ROS)levels were assessed.The mitochondrial biogenesis-related protein expressions were analyzed using Western blot or polymerase chain reaction(PCR).RESULTS:QGC treatment enhanced Rotarod test performance.Additionally,QGC significantly alleviated dexamethasone-induced mitochondrial damage,reduced mitochondrial swelling,increased respiratory chain complex enzyme activity,SDH activity,ATP content,and decreased ROS levels.PCR and western blot results revealed that QGC enhanced mitochondrial biogenesis via adenosine 5'-monophosphate-activated protein kinase(AMPK)/peroxisome proliferator-activated receptor-γcoactivator 1-alpha(PGC-1α)signaling pathway.CONCLUSIONS:QGC ameliorates dexamethasoneinduced skeletal muscle dysfunction by activating AMPK/PGC-1α,which might be developed as a therapeutic agent for treating age-related muscle weakness.
基金supported by grants from the National Natural Science Foundation of China(32071236)the National Science Fund for Distinguished Young Scholars(32225001)+6 种基金the 1.3.5 Project for Disciplines Excellence of West China Hospital,Sichuan University(ZYGD23018)Key Science and Technology Research Projects in Key Areas of the Corps(2023AB053)the National Key Research and Development Program of China(2022YFC2303700)the Joint Project of Pengzhou People's Hospital with Southwest Medical University(2024PZXNYD02)Project funded by China Postdoctoral Science Foundation(2020M683304)Sichuan Science and Technology Support Project(2021YJ0502)Post-Doctor Research Project,West China Hospital,Sichuan University(2020HXBH082).
文摘Virus-encoding RNA-dependent RNA polymerase(RdRp)is essential for genome replication and gene transcription of human coronaviruses(HCoVs),including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).We previously identified the interaction between the catalytic subunit NSP12 of SARS-CoV-2 RdRp and the host protein CREB-regulated transcription coactivator 3(CRTC3),a member of the CRTC family that regulates cyclic AMP response element-binding protein(CREB)-mediated transcriptional activation.Currently,the implication of CRTC3 in the pathogenesis of HCoVs is poorly understood.Herein,we demonstrated that CRTC3 attenuates RdRp activity and SARS-CoV-2 genome replication,therefore reducing the production of progeny viruses.The interaction of CRTC3 with NSP12 contributes to its inhibitory effect on RdRp activity.Furthermore,we expanded the suppressive effects of two other CRTC family members(CRTC1 and CRTC2)on the RdRp activities of lethal HCoVs,including SARS-CoV-2 and Middle East respiratory syndrome coronavirus(MERS-CoV),along with the CREB antagonization.Overall,our research suggests that CRTCs restrict the replication of HCoVs and are antagonized by CREB,which not only provides new insights into the replication regulation of HCoVs,but also offers important information for the development of anti-HCoV interventions.
文摘Background Some single nucleotide polymorphisms （SNPs） in the peroxisome proliferator-activated receptor-y coactivator （PGC）-1α gene have been reported to be associated with type 2 diabetes in different populations, and studies on Chinese patients yielded controversial results. The objective of this case-control study was to explore the relationship between SNPs of PGC-1α and type 2 diabetes in the southern Chinese population and to determine whether the common variants： Gly482Ser and Thr394Thr, in the PGC-1α gene have any impacts on interaction with myocyte enhancer factor （MEF） 2C. Methods The SNPs in all exons of the PGC-1α gene was investigated in 50 type 2 diabetic patients using polymerase chain reaction-single strand conformational polymorphism （PCR-SSCP） and direct sequencing. Thereafter, 263 type 2 diabetic patients and 282 healthy controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP）. A bacterial two-hybrid system and site-directed mutagenesis were used to investigate whether Gly482Ser and Thr394Thr variants in the PGC-1α gene alter the interaction with MEF2C. Results Three frequent SNPs （Thr394Thr, Gly482Ser and Thr528Thr） were found in exons of the PGC-1α gene. Only the Gly482Ser variant had a different distribution between diabetic patients and healthy subjects, with the 482Ser allele more frequent in patients than in controls （40.1% vs 29.3%, P〈0.01）. Even in controls, the 482Ser（A） carriers were more likely to have higher levels of total cholesterol and low-density lipoprotein cholesterol than the 482Gly（G） carriers. The 394A-482G-528A haplotype was associated with protection from diabetes, while the 394A-482A-528A was associated with the susceptibility to diabetes. The bacterial two-hybrid system and site-directed mutagenesis revealed that the 482Ser variant was less efficient than the 482Gly variant to interact with MEF2C, whereas the 394Thr （A） had a synergic effect on the interaction between 482Ser variant and MEF2C. Conclusions The results suggested that the 482Ser variant of PGC-1α conferred the susceptibility to type 2 diabetes in the southern Chinese population. The underlying mechanism may be attributable, at least in part, to the altered interaction between the different variants （Gly482Ser, Thr394Thr） in the PGC-1α gene and MEF2C.
基金Supported by the Sci-tech Program of Shandong Provincial Education Department (Grant No. J06N02)
文摘The GATA family consists of six members, GATA 1-6. In this study, we focused on GATA-2, which is expressed predominantly in hematopoietic progenitor cells and plays the key role in keeping these cells in the undifferentiated status. CREB-binding proteins (CBP) are essential transcriptional coacti- vators for a large number of regulated DNA-binding transcription factors, including GATA-1. But there have been no reports on whether CBP is still a co-activator of GATA-2. Here, we used the immunopre- cipitation and pull-down experiments to show that the GATA-2 and CBP were physically binding to- gether, and clarified the binding sites CH1, CH3 , CH452 and CT1430 in CBP and N-finger, C-finger and N-C-finger in GATA-2. Luciferase assay results in our experiment indicated that CBP could increase GATA-2 transcriptional activity in the dose-dependent manner. GATA-1 is mainly expressed in differen- tiated hematopoietic cells, but still has overlap expression with GATA-2. CBP is a coactivator of GATA-2 and GATA-1. The investigation on the mechanism that could decide whether CBP binds to GATA-2 to keep hematopoietic cells in the progenitor status or to GATA-1 to start differentiation will be a very in- teresting and very meaningful project in the near future.
基金supported by the National Notural Science Foundation of China,Nos.82071556 and 82271291 (both to WM)
文摘Activated G-protein-coupled receptor 39(GPR39)has been shown to attenuate inflammation by interacting with sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α).However,whether GPR39 attenuates neuropathic pain remains unclear.In this study,we established a Sprague-Dawley rat model of spared nerve injury-induced neuropathic pain and found that GPR39 expression was significantly decreased in neurons and microglia in the spinal dorsal horn compared with sham-operated rats.Intrathecal injection of TC-G 1008,a specific agonist of GPR39,significantly alleviated mechanical allodynia in the rats with spared nerve injury,improved spinal cord mitochondrial biogenesis,and alleviated neuroinflammation.These changes were abolished by GPR39 small interfering RNA(siRNA),Ex-527(SIRT1 inhibitor),and PGC-1αsiRNA.Taken together,these findings show that GPR39 activation ameliorates mechanical allodynia by activating the SIRT1/PGC-1αpathway in rats with spared nerve injury.
基金supported by the Russian Science Foundation(Grant No.23-25-00152).
文摘In mammals,the timing of physiological,biochemical and behavioral processes over a 24-h period is controlled by circadian rhythms.To entrain the master clock located in the suprachiasmatic nucleus of the hypothalamus to a precise 24-h rhythm,environmental zeitgebers are used by the circadian system.This is done primarily by signals from the retina via the retinohypothalamic tract,but other cues like exercise,feeding,temperature,anxiety,and social events have also been shown to act as non-photic zeitgebers.The recently identified myokine irisin is proposed to serve as an entraining non-photic signal of exercise.Irisin is a product of cleavage and modification from its precursor membrane fibronectin typeⅢdomain-containing protein 5(FNDC5)in response to exercise.Apart from well-known peripheral effects,such as inducing the"browning"of white adipocytes,irisin can penetrate the blood-brain barrier and display the effects on the brain.Experimental data suggest that FNDC5/irisin mediates the positive effects of physical activity on brain functions.In several brain areas,irisin induces the production of brain-derived neurotrophic factor(BDNF).In the master clock,a significant role in gating photic stimuli in the retinohypothalamic synapse for BDNF is suggested.However,the brain receptor for irisin remains unknown.In the current review,the interactions of physical activity and the irisin/BDNF axis with the circadian system are reconceptualized.
文摘Recent studies have identified mutations in PHF8, an X-linked gene encoding a JmjC domain-containing protein, as a causal factor for X-linked mental retardation （XLMR） and cleft lip/cleft palate. However, the underlying mechanism is unknown. Here we show that PHF8 is a histone demethylase and coactivator for retinoic acid receptor （RAR）. Although activities for both H3K4me3/2/1 and H3K9me2/1 demethylation were detected in cellularbased assays, reeombinant PHF8 exhibited only H3K9me2/1 demethylase activity in vitro, suggesting that PHF8 is an H3K9me2/1 demethylase whose specificity may be modulated in vivo. Importantly, a mutant PHF8 （phenylalanine at position 279 to serine） identified in the XLMR patients is defective in enzymatie activity, indicating that the loss of histone demethylase activity is causally linked with the onset of disease. In addition, we show that PHF8 binds specifically to H3K4me3/2 peptides via an N-terminal PHD finger domain. Consistent with a role for PHF8 in neuronal differentiation, knockdown of PHF8 in mouse embryonic carcinoma P19 cells impairs RA-induced neuronal differentiation, whereas overexpression of the wild-type but not the F279S mutant PHF8 drives PI9 cells toward neuronal differentiation. Furthermore, we show that PHF8 interacts with RAR~ and functions as a coactivator for RARa. Taken together, our results suggest that histone methylation modulated by PHF8 plays a critical role in neuronal differentiation.
基金supported by a grant(A121911 and HI14C2348)of the Korean Health Technology R&D Project,Ministry of Health&WelfareNational Research Foundation of Korea(NRF)(2011-0012728 and 2014R1A2A1A11051520)
文摘MicroRNA-124 contributes to neurogenesis through regulating its targets, but its expression both in the brain of Huntington＇s disease mouse models and patients is decreased. However, the effects of microRNA-124 on the progression of Huntington＇s disease have not been reported. Results from this study showed that microRNA-124 increased the latency to fall for each R6/2 Hunting- ton＇s disease transgenic mouse in the rotarod test. 5-Bromo-2＇-deoxyuridine （BrdU） staining of the striatum shows an increase in neurogenesis. In addition, brain-derived neurotrophic factor and peroxisome proliferator-activated receptor gamma coactivator 1-alpha protein levels in the striatum were increased and SRY-related HMG box transcription factor 9 protein level was de- creased. These findings suggest that microRNA-124 slows down the progression of Huntington＇s disease possibly through its important role in neuronal differentiation and survival.
文摘OBJECTIVE: To investigate whether peroxisome proliferator-activated receptor γ-coactivator-1α/nuclear respiratory factor 1(PGC-1α/NRF1) activity can protect mitochondrial function in the setting of cardiac hypertrophy and improve cardiomyocyte energy metabolism. METHODS: Cardiac hypertrophy was modeled in H9c2 cells treated with isoproterenol(ISO) to assess the effects of Shenge San( 参 蛤 散, SGS) on cell viability and mitochondrial membrane potential. We assessed mitochondrial complex m RNA levels and mitochondrial oxidative phosphorylation factor m RNA and protein levels. RESULTS: Compared with the 100 μM ISO group, cell size was significantly decreased in the 0.3 mg/m L SGS and 20 μM ZLN005(PGC-1α activator) groups(P < 0.01). Compared with the SGS(0.3) +ISO group, we observed lower phosphorylated adenosine monophosphateactivated kinase(AMPK) protein levels in the ISO and ZLN005+SGS+ISO groups(P < 0.01). Compared with the compound C group, SGS significantly increased PGC-1α expression in ISO-induced cardiac hypertrophy cells(P < 0.01), and this was inhibited by compound C pretreatment(P < 0.05). Compared with the ISO group, the mitochondrial red-green fluorescence ratio increased in the 0.3 mg/m L SGS group(P < 0.05). m RNA levels of cytochrome c oxidase subunit 1(CO1) in the ISO and compound C groups were lower than those in control group(P < 0.01), and the m RNA levels of CO1 and ATP8 were significantly lower in the ISO and compound C groups versus control(P < 0.01). Compared with the SGS(0.3) +ISO group, ATP synthetase subunit 8(ATP8) m RNA was significantly decreased in the ISO group(P < 0.01) and compound C+SGS+ISO group(P < 0.05). Compared with the SGS(0.3) +ISO group, NRF1 m RNA levels were significantly decreased(P < 0.05) in the ISO and compound C+SGS+ISO groups. CONCLUSIONS: SGS can attenuate ISO-induced cardiomyocyte hypertrophy, restore the decrease in mitochondrial membrane potential, and upregulate PGC-1α/NRF1 levels. Notably, these effects can be blocked by AMPK inhibitor-compound C.
基金Supported by the National Natural Science Foundation of China:Based on The"mi R34a/Nampt-NAD+-TAC"Pathway to Study the Mechanism of Simultaneously Treating The Phlegm And Blood Stasis in The Regulation of Glycolipid (No. 81873213)Study on the Mechanism of Simultaneously Treating the Phlegm and Blood Stasis on Glycolipid Metabolism Based on Intestinal Fat Absorption Regulated by miR-34a/Stat3-Nfil3 Pathway (82074308)Industry-University Cooperation Project for University in Fujian Province:Preparation of Monomeric Traditional Chinese Medicine Complexes Based on Nampt’s Activation of Tricarboxylic Acid Cycle And Respiratory Chain to Interfere with Glycolipid Metabolism (2022Y41016)
文摘OBJECTIVE: To evaluate the protective effects of serum containing Dangua Fang( 丹 瓜 方) on vascular endothelium damaged by oxidative stress. METHODS: Five experiments were completed in this paper. In the first experiment, we found the most suitable serum containing Dangua Fang by comparing groups with different serum containing Dangua Fang. In the second experiments we analyzed Dangua Fang influencing endothelial cell viability and apoptosis and cell cycle. The third experiment on Dangua Fang intervention of mitochondrial respiratory chain. The fourth experiment on Dangua Fang intervention of mitochondrial membrane potential. And finally, on the fifth experiment we researched the mechanism of Dangua Fang improving mitochondrial function by comparing the Na~+-k~+-ATPase and peroxisome proliferator-activated receptor-gamma coactivator-1alpha(PGC-1α) in the Dangua group with the diazoxide group and Co Q+Vit C group. RESULTS: We compared the control group in the first experiments and the OD values in DZ1 group was the most significant in all intervening groups. The recipe of DZ1(5% serum containing Dangua Fang) was used in the following experiments. Compared with the control group, cell viability, cell cycle(G2 + S), cytochrome c oxidase(COX), R3 red/green, R2 red/green, R1 red/green decreased and apoptosis, succinate dehydrogenase(SDH), green(R2 + R3), Na+-k+-ATPase, PGC-1α increased in the model group. Compared with the model group, cell viability, G2+S, COX, R3 red/green, R2 red/green, R1 red/green raised and apoptosis, green(R2 + R3), Na-K-ATPase decreased in the Dangua group;G2 + S, R3 red/green, R2 red/green, R1 red/green raised and green(R2 + R3) decreased in the Co Q + Vit C group. Na-K-ATPase increased in the combined group(P < 0.05 or < 0.01). CONCLUSIONS: Dangua Fang protects oxidative stressinduced endothelial cells damaged by promotion of mitochondrial biogenesis, reduction of Na~+-K~+-ATPase activity and regulation of mitochondrial respiratory chain function restoring mitochondrial membrane potential.
基金supported in part by a research grant from the Messer Stiftung,No.8571013(to AR).
文摘Ferroptosis is a regulated form of cell death which is considered an oxidative iron-dependent process.The lipid hydroperoxidase glutathione peroxidase 4 prevents the iron(Fe2+)-dependent formation of toxic lipid reactive oxygen species.While emerging evidence indicates that inhibition of glutathione peroxidase 4 as a hallmark of ferroptosis in many cancer cell lines,the involvement of this biochemical pathway in neuronal death remains largely unclear.Here,we investigate,first whether the ferroptosis key players are involved in the neuronal cell death induced by erastin.The second objective was to examine whether there is a cross talk between ferroptosis and autophagy.The third main was to address neuron response to erastin,with a special focus on ferritin and nuclear receptor coactivator 4-mediated ferritinophagy.To test this in neurons,erastin(0.5-8μM)was applied to hippocampal HT22 neurons for 16 hours.In addition,cells were cultured with the autophagy inhibitor,3-methyladenin(10 mM)and/or ferroptosis inhibitors,ferrostatin 1(10-20μM)or deferoxamine(10-200μM)before exposure to erastin.In this study,we demonstrated by immunofluorescence and western blot analysis,that erastin downregulates dramatically the expression of glutathione peroxidase 4,the sodium-independent cystine-glutamate antiporter and nuclear receptor coactivator 4.The protein levels of ferritin and mitochondrial ferritin in HT22 hippocampal neurons did not remarkably change following erastin treatment.In addition,we demonstrated that not only the ferroptosis inhibitor,ferrostatin1/deferoxamine abrogated the ferroptotic cell death induced by erastin in hippocampal HT22 neurons,but also the potent autophagy inhibitor,3-methyladenin.We conclude that(1)erastin-induced ferroptosis in hippocampal HT22 neurons,despite reduced nuclear receptor coactivator 4 levels,(2)that either nuclear receptor coactivator 4-mediated ferritinophagy does not occur or is of secondary importance in this model,(3)that ferroptosis seems to share some features of the autophagic cell death process.
文摘In the past,contraction-induced production of reactive oxygen species(ROS)has been implicated in oxidative stress to skeletal muscle.As research advances,clear evidence has revealed a more complete role of ROS under both physiologic and pathologic conditions.Central to the role of ROS is the redox signaling pathways that control exercise-induced major physiologic and cellular responses and adaptations,such as mitochondrial biogenesis,mitophagy,mitochondrial morphologic dynamics,antioxidant defense,and inflammation.The current review focuses on how muscle contraction and immobilization may activate or inhibit redox signalings and their impact on muscle mitochondrial homeostasis and physiologic implications.
基金Supported by International Young Scientist Fellowship:the Role of Mitochondrial Intergrity in the Pathophysiology of Kidney Yang Deficiency(No.81750110554)National Natural Science Foundation of China:Central Mechanisms of Transgenerational Phenotype of Kidney Yang Deficiency in a Rat Model(No.2018HH0085)+2 种基金National Natural Science Foundation of China:Molecular Mechanism of Blocking Cys259 and DD-mediated p75NTR Signaling Pathway to Delay the Progression of Alzheimer’s Disease(NSFC 81971309)Guangdong Basic and Applied Basic Research Foundation:Mechanism Study of Cys259 Site and DD Domain of p75NTR as New Targets for the Treatment of Alzheimer’s Disease(2019A1515011333)Sun Yat-sen University Key Training Program for Youth Teachers:Research on Glial Connexin as a New Target for Alzheimer’s Disease Treatment(F7201931620002)。
文摘OBJECTIVE:To explore whether kidney Yang deficiency(KYD)is prone to metabolic disorders may be linked to impaired mitochondrial function in thermogenesis and metabolic tissues.METHODS:A rat model of KYD was used,which was established using Sprague Dawley rat dams with warm preference subjected to herbal treatment that can improve kidney Yang.The human relevance was confirmed by reduced serum corticosterone levels,and increased preference for warm location.RESULTS:KYD Rats were underdeveloped.Adenosinetriphosphate(ATP)production was reduced in the brown fat,but increased in the muscle.However,oxidative phosphorylated complexes to generate ATP and mitochondrial biogenesis marker were reduced in both tissues.When the second insult of high-fat diet(HFD)was introduced,KYD rats gained less weight yet developed more severe lipid and glucose metabolic disorders.This may be driven by disregulated liver gluconeogenesis marker forkhead box protein O1 and lipid metabolic regulator cholesterol 7 alpha-hydroxylase.CONCLUSION:KYD rats exhibited reduced mitochondrial function in the brown fat,but were partially compensated by skeletal muscle,associated with the phenotype of warm preference and metabolic disorder,which was further exacerbated by additional HFD consumption.Future studies can focus on treatment targetting mitochondria function to reverse this phenotype.
