BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual impairment.Retinal pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its d...BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual impairment.Retinal pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its damage is an important indicator of DR.Receptor for activated C kinase 1(RACK1)activates protein kinase C-ε(PKC-ε)to promote the generation of reactive oxygen species(ROS)in RPE cells,leading to apoptosis.Therefore,we hypothesize that the activation of RACK1 under hypoxic/high-glucose conditions may promote RPE cell apoptosis by modulating PKC-ε/ROS,thereby disrupting the barrier effect of the outer blood retinal barrier and contributing to the progression of DR.AIM To investigate the role and associated underlying mechanisms of RACK1 in the development of early DR.METHODS In this study,Sprague-Dawley rats and adult RPE cell line-19(ARPE-19)cells were used as in vivo and in vitro models,respectively,to explore the role of RACK1 in mediating PKC-εin early DR.Furthermore,the impact of RACK1 on apoptosis and barrier function of RPE cells was also investigated in the former model.RESULTS Streptozotocin-induced diabetic rats showed increased apoptosis and upregulated expression of RACK1 and PKC-εproteins in RPE cells following a prolonged modeling.Similarly,ARPE-19 cells exposed to high glucose and hypoxia displayed elevated mRNA and protein levels of RACK1 and PKC-ε,accompanied by an increases in ROS production,apoptosis rate,and monolayer permeability.However,silencing RACK1 significantly downregulated the expression of PKC-εand ROS,reduced cell apoptosis and permeability,and protected barrier function.CONCLUSION RACK1 plays a significant role in the development of early DR and might serve as a potential therapeutic target for DR by regulating RPE apoptosis and barrier function.展开更多
BACKGROUND The clinical effects and detailed roles of long non-coding RNA(LncRNA)steroid receptor RNA activator 1(SRA1)in esophageal squamous cell carcinoma(ESCC)remain ambiguous.In the present study,the complementary...BACKGROUND The clinical effects and detailed roles of long non-coding RNA(LncRNA)steroid receptor RNA activator 1(SRA1)in esophageal squamous cell carcinoma(ESCC)remain ambiguous.In the present study,the complementary sites between lncRNA SRA1,miRNA-363-5p,and phospholysine phosphohistidine inorganic pyrophosphate phosphatase(LHPP)predicted via bioinformatics analysis stimulated us to hypothesize that miRNA-363-5p/LHPP axis might be required for SRA1-mediated ESCC progression.AIM To investigate the molecular events of SRA1 in the malignant behavior in ESCC.METHODS Thirty-eight ESCC tissues and paired adjacent normal tissues were acquired.SRA1 expression was detected in ESCC tissues and cell lines using quantitative reverse transcription-polymerase chain reaction.Cell counting Kit-8 assay,transwell invasion assay,glycolysis assay,and xenograft tumor model were performed to address the malignant biological behaviors of ESCC cells after the introduction of SRA1.The t-test and theχ2 test were used for comparison between groups.Survival curve analysis was performed using the Kaplan-Meier method.RESULTS SRA1 downregulation was identified in ESCC.ESCC patients exhibiting a low SRA1 expression faced shorter overall survival than those with a high SRA1 expression.The introduction of SRA1 inhibited cell proliferation,glucose uptake,and lactate production in ESCC.In vivo,the growth of ESCC was hindered by SRA1 overexpression.Then,SRA1 overexpresses the LHPP by inhibiting miRNA-363-5p.Lastly,the introduction of small interfering RNA si-LHPP or miRNA-363-5p mimic could abrogate the inhibition roles triggered by SRA1.CONCLUSION SRA1 inhibits the oncogenicity of ESCC via miRNA-363-5p/LHPP axis.The SRA1/miRNA-363-5p/LHPP pathway may be a therapeutic target for ESCC.展开更多
Objective.To investigate the effect of peroxis ome proliferator-activated recept ors(PPARs )activators on plasminogen activator inhibitor ty pe-1(PAI-1)expression in human umbilical vein e ndothelial cells and the pos...Objective.To investigate the effect of peroxis ome proliferator-activated recept ors(PPARs )activators on plasminogen activator inhibitor ty pe-1(PAI-1)expression in human umbilical vein e ndothelial cells and the possi-ble mechanism.Methods.Human umbilical vein endothelial ce lls(HUVECs )were obtained from normal fetus,and cul-tured conventionally.Then the HUVECs were exposed to test agents(linolenic acid,linoleic acid,oleic acid,stearic acid and prostaglandin J 2 respectively)in varying concentrations with fresh media.RT -PCR and ELISA were applied to determine the expression of PPARs and PAI-1in HUVECs.Results.PPARα,PPARδand PPARγmRNA were detected by using RT-PCR in HUVECs.Treatment of HUVECs with PPARαand PPARγactivators---linolenic acid,linoleic acid,oleic acid and prostaglandin J 2 respectively,but not with stearic a cid could augment PAI-I mRNA expression and protein secretion in a concentration-dependent manner.However,the mRNA expressions of 3subclasses of PPAR with their activators in HUVECs were not changed compared w ith controls.Conclusion.HUVECs express PPARs.PPARs activators may increase PAI-1expression in ECs,but the underlying mechanism remains uncle ar.Although PPARs expression was not enhanced after stimulated by their activators in ECs,the role of functionally active PPARs in regulating PA I-1expression in ECs needs to be further investigated by using transient gen e transfection assay.展开更多
Objective:To discuss the effect of insulin and metformin on amethylation and glycolipid metabolism of peroxisome proliferator-activated receptor γ coactivator-1A(PPARGC1A) of rat offspring with gestational diabetes m...Objective:To discuss the effect of insulin and metformin on amethylation and glycolipid metabolism of peroxisome proliferator-activated receptor γ coactivator-1A(PPARGC1A) of rat offspring with gestational diabetes mellitus(GDM).Methods:A total of 45 pregnant rats received the intraperitoneal injection of streptozotocin to establish the pregnant rat model of GDM.A total of 21 pregnant rats with GDM were randomly divided into three groups,with 7ruts in each group,namely the insulin group,metformin group and control group.Rats in the insulin group received the abdominal subcutaneous injection of 1 mL/kg recombinant insulin glargine at 18:00 every day.Rats in the metformin group received the intragastric infusion of metformin hydrochloride at 18:00 every day,with the first dose of 300 mg/kg.The doses of two groups were adjusted every 3 d to maintain the blood glucose level at 2.65-7.62 mmol/L.Rats in the control group received the intragastric infusion of 1 mL normal saline at 18:00 every day.After the natural delivery of pregnant rats.10 offspring rats were randomly selected from each group.At birth,4 wk and 8 wk after the birth of offspring rats,the weight of offspring rats was measured.The blood glucose level of offspring rats was measured at 4wk and 8 wk,while the level of serum insulin,triglyceride and leptin was measured at 8 wk.Results:The weight of offspring rats at birth in the insulin group and metformin group was significantly lower than the one in the control group(P<0.05),and there was no significant difference at 4 wk and 8 wk among three groups(P>0.05).The fasting blood glucose and random blood glucose in the insulin group and metformin group at 4 wk and 8 wk were all significantly lower than ones in the control group(P<0.05);there was no significant difference between the insulin group and metformin group(P>0.05).The expression of PPARGC1 A mRNA in the insulin group and metformin group was significantly higher and the methylation level of PPARGC1 A was significantly lower than the one in the control group(P<0.05),but there was no significant difference between the insulin group and metformin group(P>0.05).Insulin and leptin at 8 wk in the insulin group and metformin group were significantly higher,while triglyceride was significantly lower than the one in the control group(P<0.05);triglyceride level of rats in the insulin group was significantly higher than the one in the metformin group(P<0.05).There was no significant difference in insulin and leptin level of offspring rats between the insulin group and metformin group(P>0.05).Conclusions:GDM can induce the methylation of PPARGC1 A of offspring rats to reduce the expression of PPARGC1 A mRNA and then cause the disorder of glycolipid metabolism when the offspring rats grow up;the insulin or metformin in the treatment of pregnant rats with GDM can reduce the methylation level of PPARGC1 A and thus improve the abnormal glycolipid metabolism of offspring rats.展开更多
Cerebral ischemia/reperfusion injury is partially mediated by thrombin, which causes brain damage through protease-activated receptor 1(PAR1). However, the role and mechanisms underlying the effects of PAR1 activati...Cerebral ischemia/reperfusion injury is partially mediated by thrombin, which causes brain damage through protease-activated receptor 1(PAR1). However, the role and mechanisms underlying the effects of PAR1 activation require further elucidation. Therefore, the present study investigated the effects of the PAR1 antagonist SCH79797 in a rabbit model of global cerebral ischemia induced by cardiac arrest. SCH79797 was intravenously administered 10 minutes after the model was established. Forty-eight hours later, compared with those administered saline, rabbits receiving SCH79797 showed markedly decreased neuronal damage as assessed by serum neuron specific enolase levels and less neurological dysfunction as determined using cerebral performance category scores. Additionally, in the hippocampus, cell apoptosis, polymorphonuclear cell infiltration, and c-Jun levels were decreased, whereas extracellular signal-regulated kinase phosphorylation levels were increased. All of these changes were inhibited by the intravenous administration of the phosphoinositide 3-kinase/Akt pathway inhibitor LY29004(3 mg/kg) 10 minutes before the SCH79797 intervention. These findings suggest that SCH79797 mitigates brain injury via anti-inflammatory and anti-apoptotic effects, possibly by modulating the extracellular signal-regulated kinase, c-Jun N-terminal kinase/c-Jun and phosphoinositide 3-kinase/Akt pathways.展开更多
Prolonged activation of adenosine A1 receptor likely leads to damage of dopaminergic neurons and subsequent development of neurodegenerative diseases.However,the pathogenesis underlying long-term adenosine A1 receptor...Prolonged activation of adenosine A1 receptor likely leads to damage of dopaminergic neurons and subsequent development of neurodegenerative diseases.However,the pathogenesis underlying long-term adenosine A1 receptor activation-induced neurodegeneration remains unclear.In this study,rats were intraperitoneally injected with 5 mg/kg of the adenosine A1 receptor agonist N6-cyclopentyladenosine(CPA)for five weeks.The mobility of rats was evaluated by forced swimming test,while their cognitive capabilities were evaluated by Y-maze test.Expression of sortilin,α-synuclein,p-JUN,and c-JUN proteins in the substantia nigra were detected by western blot analysis.In addition,immunofluorescence staining of sortilin andα-synuclein was performed to detect expression in the substantia nigra.The results showed that,compared with adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine(5 mg/kg)+CPA co-treated rats,motor and memory abilities were reduced,surface expression of sortin andα-synuclein in dopaminergic neurons was reduced,and total sortilin and totalα-synuclein were increased in CPA-treated rats.MN9D cells were incubated with 500 nM CPA alone or in combination with 10μM SP600125(JNK inhibitor)for 48 hours.Quantitative real-time polymerase chain reaction analysis of sortilin andα-synuclein mRNA levels in MN9D cells revealed upregulated sortilin expression in MN9D cells cultured with CPA alone,but the combination of CPA and SP600125 could inhibit this expression.Predictions made using Jasper,PROMO,and Alibaba online databases identified a highly conserved sequence in the sortilin promoter that was predicted to bind JUN in both humans and rodents.A luciferase reporter assay of sortilin promoter plasmid-transfected HEK293T cells confirmed this prediction.After sortilin expression was inhibited by sh-SORT1,expression of p-JUN and c-JUN was detected by western blot analysis.Long-term adenosine A1 receptor activation levels upregulatedα-synuclein expression at the post-transcriptional level by affecting sortilin expression.The online tool Raptor-X-Binding and Discovery Studio 4.5 prediction software predicted that sortilin can bind toα-synuclein.Co-immunoprecipitation revealed an interaction between sortilin andα-synuclein in MN9D cells.Our findings indicate that suppression of prolonged adenosine A1 receptor activation potently inhibited sortilin expression andα-synuclein accumulation,and dramatically improved host cognition and kineticism.This study was approved by the University Committee of Animal Care and Supply at the University of Saskatchewan(approval No.AUP#20070090)in March 2007 and the Animals Ethics Committee of University of South China(approval No.LL0387-USC)in June 2017.展开更多
Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-...Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B pathway.CYLD is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly expressed.Emerging studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like behaviors.However,the precise role of CYLD in glutamatergic neurons is largely unknown.Here,we first proposed involvement of CYLD in cued fear expression.We next constructed transgenic model mice with specific deletion of Cyld from glutamatergic neurons.Our results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male mice.Further,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male mice.Altogether,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial activation.This may contribute,at least in part,to cued fear expression.展开更多
Summary: Activated protein C (APC), a natural anticoagulant, has been reported to exert direct vascu- loprotective, neural protective, anti-inflammatory, and proneurogenic activities in the central nervous system. ...Summary: Activated protein C (APC), a natural anticoagulant, has been reported to exert direct vascu- loprotective, neural protective, anti-inflammatory, and proneurogenic activities in the central nervous system. This study was aimed to explore the neuroprotective effects and potential mechanisms of APC on the neurovascular unit of neonatal rats with intrauterine infection-induced white matter injury. In- traperitoneal injection of 300 ~tg/kg lipopolysaccharide (LPS) was administered consecutively to preg- nant Sprague-Dawley rats at embryonic days 19 and 20 to establish the rat model of intrauterine infec- tion-induced white matter injury. Control rats were injected with an equivalent amount of sterile saline on the same time. APC at the dosage of 0.2 mg/kg was intraperitoneally injected to neonatal rats imme- diately after birth. Brain tissues were collected at postnatal day 7 and stained with hematoxylin and eo- sin (H&E). Immunohistochemistry was used to evaluate myelin basic protein (MBP) expression in the periventricular white matter region. Blood-brain barrier (BBB) permeability and brain water content ~were measured using Evens Blue dye and wet/dry weight method. Double immunofluorescence staining and real-time quantitative PCR were performed to detect microglial activation and the expression of protease activated receptor 1 (PAR1). Typical pathological changes of white matter injury were ob- served in rat brains exposed to LPS, and MBP expression in the periventricular region was significantly decreased. BBB was disrupted and the brain water content was increased. Microglia were largely acti- vated and the mRNA and protein levels of PAR1 were elevated. APC administration ameliorated the pathological lesions of the white matter and increased MBP expression. BBB permeability and brain water content were reduced. Microglia activation was inhibited and the PAR1 mRNA and protein ex- pression levels were both down-regulated. Our results suggested that APC exerted neuroprotective ef- fects on multiple components of the neurovascular unit in neonatal rats with intrauterine infec- tion-induced white matter injury, and the underlying mechanisms might involve decreased expression of PAR1.展开更多
To date there is no treatment able to stop or slow down the loss of dopaminergic neurons that characterizes Parkinson’s disease.It was recently observed in a rodent model of Alzheimer’s disease that the interaction ...To date there is no treatment able to stop or slow down the loss of dopaminergic neurons that characterizes Parkinson’s disease.It was recently observed in a rodent model of Alzheimer’s disease that the interaction between the α7 subtype of nicotinic acetylcholine receptor(α7-nAChR)and sigma-1 receptor(σ1-R)could exert neuroprotective effects through the modulation of neuroinflammation which is one of the key components of the pathophysiology of Parkinson’s disease.In this context,the aim of the present study was to assess the effects of the concomitant administration of N-(3R)-1-azabicyclo[2.2.2]oct-3-yl-furo[2,3-c]pyridine-5-carboxamide(PHA)543613 as an α7-nAChR agonist and 2-(4-morpholinethyl)1-phenylcyclohexanecarboxylate(PRE)-084 as aσ1-R agonist in a well-characterized 6-hydroxydopamine rat model of Parkinson’s disease.The animals received either vehicle separately or the dual therapy PHA/PRE once a day until day 14 postlesion.Although no effect was noticed in the amphetamine-induced rotation test,our data has shown that the PHA/PRE treatment induced partial protection of the dopaminergic neurons(15-20%),assessed by the dopamine transporter density in the striatum and immunoreactive tyrosine hydroxylase in the substantia nigra.Furthermore,this dual therapy reduced the degree of glial activation consecutive to the 6-hydroxydopamine lesion,i.e,the 18 kDa translocation protein density and glial fibrillary acidic protein staining in the striatum,and the CD11b and glial fibrillary acidic protein staining in the substantia nigra.Hence,this study reports for the first time that concomitant activation of α7-nAChR andσ1-R can provide a partial recovery of the nigro-striatal dopaminergic neurons through the modulation of microglial activation.The study was approved by the Regional Ethics Committee(CEEA Val de Loire n°19)validated this protocol(Authorization N°00434.02)on May 15,2014.展开更多
Objective: To explore the relationship between peroxisome proliferator activated receptor-gamma (PPARγ) and peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) expression in gastric carcinoma ...Objective: To explore the relationship between peroxisome proliferator activated receptor-gamma (PPARγ) and peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) expression in gastric carcinoma (GC), and analyze their correlations with clinicopathological features and clinical outcomes of patients. Methods:The two-step immunohistochemical method was used to detect the expression of PPARγ and PGC-1 in 179 cases of GC, and 108 cases of matched normal gastric mucosa. Besides, 16 cases of fresh GC specimens and corresponding normal gastric mucosa were detected for PGC-1 expression with Western blotting. Results: The positive rates of PPART and PGC-1 expression were significantly lower in GC (54.75%, 49.16%) than in normal gastric mucosa (70.37%, 71.30%), respectively (P〈0.05). The decreased expression of PGC-1 in GC was confirmed ha our Western blot analysis (P=0.004). PPAR7 and PGC-1 expressions were related to Lauren's types ofGC (P〈0.05). Positive correlation was found between PPART and PGC-1 expression in GC (rk=0.422, P〈0.001). The survival time of PPART negative and positive patients was 36.6±3.0 vs. 38.5_+2.7 months, and no statistical difference was found between the 5-year survival rates of two groups (34.4% vs. 44.1%, P=0.522, log-rank test); the survival time of PGC-1 negative and positive patients was 36.2±2.8 vs. 39.9±2.9 months, while no statistical difference was found between the 5-year survival rates of the two groups (32.0% vs. 48.2%, P=0.462, log-rank test) Conclusions'. Decreased expression of PPARγand PGC-1 in GC was related to the Lauren's classification. Their expressions in GC were positively correlated, indicating that their fimctions in gastric carcinogenesis may be closely related.展开更多
20 Typical flavonoids were selected for study on the interaction between them and PIM-1 kinase with the comparative molecular field analysis method(CoMFA) as well as the comparative molecular similarity index analys...20 Typical flavonoids were selected for study on the interaction between them and PIM-1 kinase with the comparative molecular field analysis method(CoMFA) as well as the comparative molecular similarity index analysis method(CoMSIA) based on molecule docking.3D-QSAR models between these flavonoids and receptor PIM-1 kinase were established.The obtained optimal cross-validation correlation coefficient Q2 for CoMFA model was 0.582,and the non-cross-validation correlation coefficient R2 was 0.955;the corresponding values for CoMSIA model were 0.790 and 0.974,respectively.These two models showed fairly fine stability and predictive ability.In addition,molecule docking results revealed the key residues in the receptor cavity and their specific action ways with flavonoids.展开更多
基金Supported by National Natural Science Foundation of China,No.82260211Key Research and Development Project in Jiangxi Province,No.20203BBG73058Chinese Medicine Science and Technology Project in Jiangxi Province,No.2020A0166.
文摘BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual impairment.Retinal pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its damage is an important indicator of DR.Receptor for activated C kinase 1(RACK1)activates protein kinase C-ε(PKC-ε)to promote the generation of reactive oxygen species(ROS)in RPE cells,leading to apoptosis.Therefore,we hypothesize that the activation of RACK1 under hypoxic/high-glucose conditions may promote RPE cell apoptosis by modulating PKC-ε/ROS,thereby disrupting the barrier effect of the outer blood retinal barrier and contributing to the progression of DR.AIM To investigate the role and associated underlying mechanisms of RACK1 in the development of early DR.METHODS In this study,Sprague-Dawley rats and adult RPE cell line-19(ARPE-19)cells were used as in vivo and in vitro models,respectively,to explore the role of RACK1 in mediating PKC-εin early DR.Furthermore,the impact of RACK1 on apoptosis and barrier function of RPE cells was also investigated in the former model.RESULTS Streptozotocin-induced diabetic rats showed increased apoptosis and upregulated expression of RACK1 and PKC-εproteins in RPE cells following a prolonged modeling.Similarly,ARPE-19 cells exposed to high glucose and hypoxia displayed elevated mRNA and protein levels of RACK1 and PKC-ε,accompanied by an increases in ROS production,apoptosis rate,and monolayer permeability.However,silencing RACK1 significantly downregulated the expression of PKC-εand ROS,reduced cell apoptosis and permeability,and protected barrier function.CONCLUSION RACK1 plays a significant role in the development of early DR and might serve as a potential therapeutic target for DR by regulating RPE apoptosis and barrier function.
基金Supported by Innovative Team of Jiangsu Province,No.CXTDA2017042Jiangsu Provincial Medical Youth Talent,No.QNRC2016508In-Hospital Project of Taizhou People's Hospital,No.ZL201930.
文摘BACKGROUND The clinical effects and detailed roles of long non-coding RNA(LncRNA)steroid receptor RNA activator 1(SRA1)in esophageal squamous cell carcinoma(ESCC)remain ambiguous.In the present study,the complementary sites between lncRNA SRA1,miRNA-363-5p,and phospholysine phosphohistidine inorganic pyrophosphate phosphatase(LHPP)predicted via bioinformatics analysis stimulated us to hypothesize that miRNA-363-5p/LHPP axis might be required for SRA1-mediated ESCC progression.AIM To investigate the molecular events of SRA1 in the malignant behavior in ESCC.METHODS Thirty-eight ESCC tissues and paired adjacent normal tissues were acquired.SRA1 expression was detected in ESCC tissues and cell lines using quantitative reverse transcription-polymerase chain reaction.Cell counting Kit-8 assay,transwell invasion assay,glycolysis assay,and xenograft tumor model were performed to address the malignant biological behaviors of ESCC cells after the introduction of SRA1.The t-test and theχ2 test were used for comparison between groups.Survival curve analysis was performed using the Kaplan-Meier method.RESULTS SRA1 downregulation was identified in ESCC.ESCC patients exhibiting a low SRA1 expression faced shorter overall survival than those with a high SRA1 expression.The introduction of SRA1 inhibited cell proliferation,glucose uptake,and lactate production in ESCC.In vivo,the growth of ESCC was hindered by SRA1 overexpression.Then,SRA1 overexpresses the LHPP by inhibiting miRNA-363-5p.Lastly,the introduction of small interfering RNA si-LHPP or miRNA-363-5p mimic could abrogate the inhibition roles triggered by SRA1.CONCLUSION SRA1 inhibits the oncogenicity of ESCC via miRNA-363-5p/LHPP axis.The SRA1/miRNA-363-5p/LHPP pathway may be a therapeutic target for ESCC.
文摘Objective.To investigate the effect of peroxis ome proliferator-activated recept ors(PPARs )activators on plasminogen activator inhibitor ty pe-1(PAI-1)expression in human umbilical vein e ndothelial cells and the possi-ble mechanism.Methods.Human umbilical vein endothelial ce lls(HUVECs )were obtained from normal fetus,and cul-tured conventionally.Then the HUVECs were exposed to test agents(linolenic acid,linoleic acid,oleic acid,stearic acid and prostaglandin J 2 respectively)in varying concentrations with fresh media.RT -PCR and ELISA were applied to determine the expression of PPARs and PAI-1in HUVECs.Results.PPARα,PPARδand PPARγmRNA were detected by using RT-PCR in HUVECs.Treatment of HUVECs with PPARαand PPARγactivators---linolenic acid,linoleic acid,oleic acid and prostaglandin J 2 respectively,but not with stearic a cid could augment PAI-I mRNA expression and protein secretion in a concentration-dependent manner.However,the mRNA expressions of 3subclasses of PPAR with their activators in HUVECs were not changed compared w ith controls.Conclusion.HUVECs express PPARs.PPARs activators may increase PAI-1expression in ECs,but the underlying mechanism remains uncle ar.Although PPARs expression was not enhanced after stimulated by their activators in ECs,the role of functionally active PPARs in regulating PA I-1expression in ECs needs to be further investigated by using transient gen e transfection assay.
基金supported by Shandong Natural Science Fund(Y2008c170)
文摘Objective:To discuss the effect of insulin and metformin on amethylation and glycolipid metabolism of peroxisome proliferator-activated receptor γ coactivator-1A(PPARGC1A) of rat offspring with gestational diabetes mellitus(GDM).Methods:A total of 45 pregnant rats received the intraperitoneal injection of streptozotocin to establish the pregnant rat model of GDM.A total of 21 pregnant rats with GDM were randomly divided into three groups,with 7ruts in each group,namely the insulin group,metformin group and control group.Rats in the insulin group received the abdominal subcutaneous injection of 1 mL/kg recombinant insulin glargine at 18:00 every day.Rats in the metformin group received the intragastric infusion of metformin hydrochloride at 18:00 every day,with the first dose of 300 mg/kg.The doses of two groups were adjusted every 3 d to maintain the blood glucose level at 2.65-7.62 mmol/L.Rats in the control group received the intragastric infusion of 1 mL normal saline at 18:00 every day.After the natural delivery of pregnant rats.10 offspring rats were randomly selected from each group.At birth,4 wk and 8 wk after the birth of offspring rats,the weight of offspring rats was measured.The blood glucose level of offspring rats was measured at 4wk and 8 wk,while the level of serum insulin,triglyceride and leptin was measured at 8 wk.Results:The weight of offspring rats at birth in the insulin group and metformin group was significantly lower than the one in the control group(P<0.05),and there was no significant difference at 4 wk and 8 wk among three groups(P>0.05).The fasting blood glucose and random blood glucose in the insulin group and metformin group at 4 wk and 8 wk were all significantly lower than ones in the control group(P<0.05);there was no significant difference between the insulin group and metformin group(P>0.05).The expression of PPARGC1 A mRNA in the insulin group and metformin group was significantly higher and the methylation level of PPARGC1 A was significantly lower than the one in the control group(P<0.05),but there was no significant difference between the insulin group and metformin group(P>0.05).Insulin and leptin at 8 wk in the insulin group and metformin group were significantly higher,while triglyceride was significantly lower than the one in the control group(P<0.05);triglyceride level of rats in the insulin group was significantly higher than the one in the metformin group(P<0.05).There was no significant difference in insulin and leptin level of offspring rats between the insulin group and metformin group(P>0.05).Conclusions:GDM can induce the methylation of PPARGC1 A of offspring rats to reduce the expression of PPARGC1 A mRNA and then cause the disorder of glycolipid metabolism when the offspring rats grow up;the insulin or metformin in the treatment of pregnant rats with GDM can reduce the methylation level of PPARGC1 A and thus improve the abnormal glycolipid metabolism of offspring rats.
基金supported by the Natural Science Foundation of Hubei Province of China,No.2010CDB09101
文摘Cerebral ischemia/reperfusion injury is partially mediated by thrombin, which causes brain damage through protease-activated receptor 1(PAR1). However, the role and mechanisms underlying the effects of PAR1 activation require further elucidation. Therefore, the present study investigated the effects of the PAR1 antagonist SCH79797 in a rabbit model of global cerebral ischemia induced by cardiac arrest. SCH79797 was intravenously administered 10 minutes after the model was established. Forty-eight hours later, compared with those administered saline, rabbits receiving SCH79797 showed markedly decreased neuronal damage as assessed by serum neuron specific enolase levels and less neurological dysfunction as determined using cerebral performance category scores. Additionally, in the hippocampus, cell apoptosis, polymorphonuclear cell infiltration, and c-Jun levels were decreased, whereas extracellular signal-regulated kinase phosphorylation levels were increased. All of these changes were inhibited by the intravenous administration of the phosphoinositide 3-kinase/Akt pathway inhibitor LY29004(3 mg/kg) 10 minutes before the SCH79797 intervention. These findings suggest that SCH79797 mitigates brain injury via anti-inflammatory and anti-apoptotic effects, possibly by modulating the extracellular signal-regulated kinase, c-Jun N-terminal kinase/c-Jun and phosphoinositide 3-kinase/Akt pathways.
基金supported by the National Natural Sciences Foundation of China,No.81770460(to YCL)the Postdoctoral Research Fellowship of the Saskatchewan Health Research Foundation,No.SHRF,4144(to YCL)+2 种基金the third level of the Chuanshan Talent project of the University of South China,No.2017CST20(to YCL)the Aid Program,No.2017KJ268 and the Key Lab for Clinical Anatomy&Reproductive Medicine,No.2017KJ182 from the Science and Technology Bureau of Hengyang City,China(to YCL and XC)the Postgraduate Student Research Innovation Projects of Hunan Province,China,No.CX2018B62(to ABG)
文摘Prolonged activation of adenosine A1 receptor likely leads to damage of dopaminergic neurons and subsequent development of neurodegenerative diseases.However,the pathogenesis underlying long-term adenosine A1 receptor activation-induced neurodegeneration remains unclear.In this study,rats were intraperitoneally injected with 5 mg/kg of the adenosine A1 receptor agonist N6-cyclopentyladenosine(CPA)for five weeks.The mobility of rats was evaluated by forced swimming test,while their cognitive capabilities were evaluated by Y-maze test.Expression of sortilin,α-synuclein,p-JUN,and c-JUN proteins in the substantia nigra were detected by western blot analysis.In addition,immunofluorescence staining of sortilin andα-synuclein was performed to detect expression in the substantia nigra.The results showed that,compared with adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine(5 mg/kg)+CPA co-treated rats,motor and memory abilities were reduced,surface expression of sortin andα-synuclein in dopaminergic neurons was reduced,and total sortilin and totalα-synuclein were increased in CPA-treated rats.MN9D cells were incubated with 500 nM CPA alone or in combination with 10μM SP600125(JNK inhibitor)for 48 hours.Quantitative real-time polymerase chain reaction analysis of sortilin andα-synuclein mRNA levels in MN9D cells revealed upregulated sortilin expression in MN9D cells cultured with CPA alone,but the combination of CPA and SP600125 could inhibit this expression.Predictions made using Jasper,PROMO,and Alibaba online databases identified a highly conserved sequence in the sortilin promoter that was predicted to bind JUN in both humans and rodents.A luciferase reporter assay of sortilin promoter plasmid-transfected HEK293T cells confirmed this prediction.After sortilin expression was inhibited by sh-SORT1,expression of p-JUN and c-JUN was detected by western blot analysis.Long-term adenosine A1 receptor activation levels upregulatedα-synuclein expression at the post-transcriptional level by affecting sortilin expression.The online tool Raptor-X-Binding and Discovery Studio 4.5 prediction software predicted that sortilin can bind toα-synuclein.Co-immunoprecipitation revealed an interaction between sortilin andα-synuclein in MN9D cells.Our findings indicate that suppression of prolonged adenosine A1 receptor activation potently inhibited sortilin expression andα-synuclein accumulation,and dramatically improved host cognition and kineticism.This study was approved by the University Committee of Animal Care and Supply at the University of Saskatchewan(approval No.AUP#20070090)in March 2007 and the Animals Ethics Committee of University of South China(approval No.LL0387-USC)in June 2017.
基金supported by the National Natural Science Foundation of China,Nos.32371065(to CL)and 32170950(to LY)the Natural Science Foundation of the Guangdong Province,No.2023A1515010899(to CL)the Science and Technology Projects in Guangzhou,Nos.2023A4J0578 and 2024A03J0180(to CW)。
文摘Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B pathway.CYLD is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly expressed.Emerging studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like behaviors.However,the precise role of CYLD in glutamatergic neurons is largely unknown.Here,we first proposed involvement of CYLD in cued fear expression.We next constructed transgenic model mice with specific deletion of Cyld from glutamatergic neurons.Our results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male mice.Further,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male mice.Altogether,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial activation.This may contribute,at least in part,to cued fear expression.
基金supported by grants from National Natural Science Foundation of China(No.81471519 and No.81401277)the Program for Changjiang Scholars and Innovative Research Team in University of China(No.IRT_14R20)
文摘Summary: Activated protein C (APC), a natural anticoagulant, has been reported to exert direct vascu- loprotective, neural protective, anti-inflammatory, and proneurogenic activities in the central nervous system. This study was aimed to explore the neuroprotective effects and potential mechanisms of APC on the neurovascular unit of neonatal rats with intrauterine infection-induced white matter injury. In- traperitoneal injection of 300 ~tg/kg lipopolysaccharide (LPS) was administered consecutively to preg- nant Sprague-Dawley rats at embryonic days 19 and 20 to establish the rat model of intrauterine infec- tion-induced white matter injury. Control rats were injected with an equivalent amount of sterile saline on the same time. APC at the dosage of 0.2 mg/kg was intraperitoneally injected to neonatal rats imme- diately after birth. Brain tissues were collected at postnatal day 7 and stained with hematoxylin and eo- sin (H&E). Immunohistochemistry was used to evaluate myelin basic protein (MBP) expression in the periventricular white matter region. Blood-brain barrier (BBB) permeability and brain water content ~were measured using Evens Blue dye and wet/dry weight method. Double immunofluorescence staining and real-time quantitative PCR were performed to detect microglial activation and the expression of protease activated receptor 1 (PAR1). Typical pathological changes of white matter injury were ob- served in rat brains exposed to LPS, and MBP expression in the periventricular region was significantly decreased. BBB was disrupted and the brain water content was increased. Microglia were largely acti- vated and the mRNA and protein levels of PAR1 were elevated. APC administration ameliorated the pathological lesions of the white matter and increased MBP expression. BBB permeability and brain water content were reduced. Microglia activation was inhibited and the PAR1 mRNA and protein ex- pression levels were both down-regulated. Our results suggested that APC exerted neuroprotective ef- fects on multiple components of the neurovascular unit in neonatal rats with intrauterine infec- tion-induced white matter injury, and the underlying mechanisms might involve decreased expression of PAR1.
基金supported by Inserm(to SV,LFF,CT,JV,SB,SS,SC)by the Labex IRON(ANR-11-LABX-18-01:to all authors).
文摘To date there is no treatment able to stop or slow down the loss of dopaminergic neurons that characterizes Parkinson’s disease.It was recently observed in a rodent model of Alzheimer’s disease that the interaction between the α7 subtype of nicotinic acetylcholine receptor(α7-nAChR)and sigma-1 receptor(σ1-R)could exert neuroprotective effects through the modulation of neuroinflammation which is one of the key components of the pathophysiology of Parkinson’s disease.In this context,the aim of the present study was to assess the effects of the concomitant administration of N-(3R)-1-azabicyclo[2.2.2]oct-3-yl-furo[2,3-c]pyridine-5-carboxamide(PHA)543613 as an α7-nAChR agonist and 2-(4-morpholinethyl)1-phenylcyclohexanecarboxylate(PRE)-084 as aσ1-R agonist in a well-characterized 6-hydroxydopamine rat model of Parkinson’s disease.The animals received either vehicle separately or the dual therapy PHA/PRE once a day until day 14 postlesion.Although no effect was noticed in the amphetamine-induced rotation test,our data has shown that the PHA/PRE treatment induced partial protection of the dopaminergic neurons(15-20%),assessed by the dopamine transporter density in the striatum and immunoreactive tyrosine hydroxylase in the substantia nigra.Furthermore,this dual therapy reduced the degree of glial activation consecutive to the 6-hydroxydopamine lesion,i.e,the 18 kDa translocation protein density and glial fibrillary acidic protein staining in the striatum,and the CD11b and glial fibrillary acidic protein staining in the substantia nigra.Hence,this study reports for the first time that concomitant activation of α7-nAChR andσ1-R can provide a partial recovery of the nigro-striatal dopaminergic neurons through the modulation of microglial activation.The study was approved by the Regional Ethics Committee(CEEA Val de Loire n°19)validated this protocol(Authorization N°00434.02)on May 15,2014.
基金supported by the National Natural Science Foundation of China(No.8107165030973503)the Supporting Project for Climbing Scholars in Liaoning Provincial Universities,China(2009-2012)
文摘Objective: To explore the relationship between peroxisome proliferator activated receptor-gamma (PPARγ) and peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) expression in gastric carcinoma (GC), and analyze their correlations with clinicopathological features and clinical outcomes of patients. Methods:The two-step immunohistochemical method was used to detect the expression of PPARγ and PGC-1 in 179 cases of GC, and 108 cases of matched normal gastric mucosa. Besides, 16 cases of fresh GC specimens and corresponding normal gastric mucosa were detected for PGC-1 expression with Western blotting. Results: The positive rates of PPART and PGC-1 expression were significantly lower in GC (54.75%, 49.16%) than in normal gastric mucosa (70.37%, 71.30%), respectively (P〈0.05). The decreased expression of PGC-1 in GC was confirmed ha our Western blot analysis (P=0.004). PPAR7 and PGC-1 expressions were related to Lauren's types ofGC (P〈0.05). Positive correlation was found between PPART and PGC-1 expression in GC (rk=0.422, P〈0.001). The survival time of PPART negative and positive patients was 36.6±3.0 vs. 38.5_+2.7 months, and no statistical difference was found between the 5-year survival rates of two groups (34.4% vs. 44.1%, P=0.522, log-rank test); the survival time of PGC-1 negative and positive patients was 36.2±2.8 vs. 39.9±2.9 months, while no statistical difference was found between the 5-year survival rates of the two groups (32.0% vs. 48.2%, P=0.462, log-rank test) Conclusions'. Decreased expression of PPARγand PGC-1 in GC was related to the Lauren's classification. Their expressions in GC were positively correlated, indicating that their fimctions in gastric carcinogenesis may be closely related.
基金Sponsored by the National Natural Science Foundation of China (No. 20737001,20977046)the National Basic Research Program of China (No. 2009CB42160-4)
文摘20 Typical flavonoids were selected for study on the interaction between them and PIM-1 kinase with the comparative molecular field analysis method(CoMFA) as well as the comparative molecular similarity index analysis method(CoMSIA) based on molecule docking.3D-QSAR models between these flavonoids and receptor PIM-1 kinase were established.The obtained optimal cross-validation correlation coefficient Q2 for CoMFA model was 0.582,and the non-cross-validation correlation coefficient R2 was 0.955;the corresponding values for CoMSIA model were 0.790 and 0.974,respectively.These two models showed fairly fine stability and predictive ability.In addition,molecule docking results revealed the key residues in the receptor cavity and their specific action ways with flavonoids.