Objective:To investigate the expression of Runx3 and TGF-β_1 protein in the colon from rats with irritable bowel syndrome(IBS).Methods:Rat model for IBS was established by intracolonic instillation with acetic acid a...Objective:To investigate the expression of Runx3 and TGF-β_1 protein in the colon from rats with irritable bowel syndrome(IBS).Methods:Rat model for IBS was established by intracolonic instillation with acetic acid and restraint stress methods,which was confirmed by determinating the visceral sensitivity of the animals,including abdominal withdrawal reflex (AWR) score and the electronic behavior of the abdomen wall.The rats were randomly assigned into three groups:IBS,group(restraint stress,n=25);IBS_2 group(both instillation with acetic acid and restraint stress,n=25) and Control group(n=16).The colonic tissue samples were collected for histological study and the expression of Runx3 and TGF-β_1 proteins were detected by immunohistochemistry.Meanwhile,the relationship of these two proteins was calculated. Results:Visceral hypersensitivity(AWR and abdominal electrical activity) was significantly enhanced in IBS,and IBS_2 groups than other groups.The colon tissue in all groups did not show any signs of inflammation.Furthermore,the expression of Runx3 and TGF-β_1 protein in the colon from all groups show no significant difference(P>0.05),with no remarkable relevancy between each other(P>0.05).Conclusions:The rat model for IBS was successfully established. We did not find any significant changes in the expression of Runx3 and TGF-β_1 protein in the colon tissue from IBS rats,suggesting that the quantitative changes may be not the way by which Runx3 and TGF-β_1 protein play their roles in IBS.The accurate roles of Runx3 and TGF-β_1 proteins in the pathogenesis of IBS remains to be further studied.展开更多
Objective:To investigate the role of Runx3 protein and TGF-β_1 in the pathogenesis of irritable bowel syndrome(IBS),as well as the correlation of these two proteins.Methods:Colonic tissue was collected from patients ...Objective:To investigate the role of Runx3 protein and TGF-β_1 in the pathogenesis of irritable bowel syndrome(IBS),as well as the correlation of these two proteins.Methods:Colonic tissue was collected from patients with IBS and normal persons.The colonic expression of Runx3 protein and TGF-β_1 was detected with immunohislochemistry method.Semi-quantitative analysis was used to evaluate the staining degree of these two proteins.Results:Compared with their counterparts,patients with IBS did not show any changes in the colonic expression of Runx3 protein and TGF-β_1(P>0.05).Interestingly,there was a significant correlation between Runx3 protein and TGF-β_1 in patients with IBS(P<0.05).Conclusions:The role of Runx3 protein and TGF-β_1 in the pathogenesis of IBS remains to be further studied.展开更多
A progressive neurodegenerative disease,Alzheimer’s disease(AD).Studies suggest that highly expressed protein isoaspartate methyltransferase 1(PCMT1)in brain tissue.In the current study,we explored the effects of neu...A progressive neurodegenerative disease,Alzheimer’s disease(AD).Studies suggest that highly expressed protein isoaspartate methyltransferase 1(PCMT1)in brain tissue.In the current study,we explored the effects of neural stem cell-conditioned medium(NSC-CDM)on the PCMT1/MST1 pathway to alleviate Aβ_(25-35)-induced damage in SH-SY5Y cells.Our data suggested that Aβ_(25-35) markedly inhibited cell viability.NSC-CDM or Neural stem cell-complete medium(NSC-CPM)had a suppression effect on toxicity when treatment with Aβ_(25-35),with a greater effect observed with NSC-CDM.Aβ_(25-35)+NSC-CDM group exhibited an increase in PCMT1 expression.sh-PCMT1 markedly decreased cell proliferation and suppressed the protective role of NSC-CDM through the induction of apoptosis and improved p-MST1 expression.Overexpression of PCMT1 reversed the Aβ_(25-35)-induced decrease in cell proliferation and apoptosis.In summary,our findings suggest that NSC-CDM corrects the Aβ_(25-35)-induced damage to cells by improving PCMT1 expressions,which in turn reduces phosphorylation of MST1.展开更多
Background SMAD proteins have recently been identified as the first family of putative transforming growth factor-β_1(TGF-β_1) signal transducers. This study was to investigate the effects of TGF-β_1 and signal pr...Background SMAD proteins have recently been identified as the first family of putative transforming growth factor-β_1(TGF-β_1) signal transducers. This study was to investigate the effects of TGF-β_1 and signal protein Smad3 on rat cardiac hypertrophy.Methods The incorporation of [3H]-leucine was measured to determine the hypertrophy of cardiomyocyte incubated with different doses of TGF-β_1 in cultured neonatal cardiomyocytes. The model of rat cardiac hypertrophy was produced with constriction of the abdominal aorta. At different times after the operation, rats were killed, and their left ventricular mass index (LVMI) determined. The mRNA expression of TGF-β_1 and Smad3 of cultured cells and hypertrophic left ventricles were assessed by RT-PCR. The protein expression of Smad3 was assessed by Western blot.Results In cultured neonatal cardiomyocytes, TGF-β_1 significantly promoted incorporation of [3H]-leucine. With the concentration of 3 pg/L, it increased the expression of Smad3 in mRNA and protein levels after 15 minutes, and continued for up to 8 hours of cultured cardiomyocytes. The LVMI and the expression of TGF-β_1 (mRNA) and Smad3 (mRNA and protein) of hypertrophic left ventricle were increased by day 3 after the operation and continued to the 4th week. The peak expression of these was in the second week after operation.Conclusion TGF-β_1 has positive effects on rat cardiomyocyte hypertrophy. Signal protein Smad3 could be related to the pathologic progression of rat cardiac hypertrophy.展开更多
As the leading cause of worldwide hospital-acquired infection,Clostridioides difficile(C.difficile)infection has caused heavy economic and hospitalized burden,while its pathogenesis is not fully understood.Toxin B(Tcd...As the leading cause of worldwide hospital-acquired infection,Clostridioides difficile(C.difficile)infection has caused heavy economic and hospitalized burden,while its pathogenesis is not fully understood.Toxin B(Tcd B)is one of the major virulent factors of C.difficile.Recently,CSPG4 and FZD2 were reported to be the receptors that mediate Tcd B cellular entry.However,genetic ablation of genes encoding these receptors failed to completely block Tcd B entry,implicating the existence of alternative receptor(s)for this toxin.Here,by employing the CRISPR-Cas9 screen in CSPG4-deficient He La cells,we identified LDL receptor-related protein-1(LRP1)as a novel receptor for Tcd B.Knockout of LRP1 in both CSPG4-deficient He La cells and colonic epithelium Caco2 cells conferred cells with increased Tcd B resistance,while LRP1 overexpression sensitized cells to Tcd B at a low concentration.Co-immunoprecipitation assay showed that LRP1 interacts with full-length Tcd B.Moreover,CROPs domain,which is dispensable for Tcd B’s interaction with CSPG4 and FZD2,is sufficient for binding to LRP1.As such,our study provided evidence for a novel mechanism of Tcd B entry and suggested potential therapeutic targets for treating C.difficile infection.展开更多
AIM:To investigate the pathway(s)mediating rat antral circular smooth muscle contractile responses to the cholinomimetic agent,bethanechol and the subtypes of muscarinic receptors mediating the cholinergic contraction...AIM:To investigate the pathway(s)mediating rat antral circular smooth muscle contractile responses to the cholinomimetic agent,bethanechol and the subtypes of muscarinic receptors mediating the cholinergic contraction. METHODS:Circular smooth muscle strips from the antrum of Sprague-Dawley rats were mounted in muscle baths in Krebs buffer.Isometric tension was recorded.Cumulative concentration-response curves were obtained for(+)-cis- dioxolane(cD),a nonspecific muscarinic agonist,at 10^(-8)- 10^(-4)mol/L,in the presence of tetrodotoxin(TTX,10^(-7)mol/L). Results were normalized to cross sectional area.A repeat concentration-response curve was obtained after incubation of the muscle for 90 min with antagonists for M1(pirenzepine), M2(methoctramine)and M3(darifenadn)muscarinic receptor subtypes.The sensitivity to PTX was tested by the ip injection of 100 mg/kg of PTX 5 d before the experiment.The antral circular smooth muscles were removed from PTX-treated and non-treated rats as strips and dispersed smooth muscle cells to identify whether PTX-linked pathway mediated the contractility to bethanechol. RESULTS:A dose-dependent contractile response observed with bethanechol,was not affected by TTx.The pretreatment of rats with pertussis toxin decreased the contraction induced by bethanechol.Lack of calcium as well as the presence of the L-type calcium channel blocker,nifedipine,also inhibited the cholinergic contraction,with a reduction in response from 2.5±0.4 g/mm^2 to 1.2±0.4 g/mm^2(P<0.05).The dose- response curves were shifted to the right by muscarinic antagonists in the following order of affinity:darifenacin (M_3)>methocramine(M_2)>pirenzepine(M_1). CONCLUSION:The muscarinic receptors-dependent contraction of rat antral circular smooth muscles was linked to the signal transduction pathway(s)involving pertussis-toxin sensitive GTP-binding proteins and to extracellular calcium via L-type voltage gated calcium channels.The presence of the residual contractile response after the treatment with nifedipine,suggests that an additional pathway could mediate the cholinergic contraction.The involvement of more than one muscarinic receptor(functionally predominant type 3 over type 2)also suggests more than one pathway mediating the cholinergic contraction in rat antrum.展开更多
基金Supported by Natural Science Fundation of Hainan Province 2008(No 30855)
文摘Objective:To investigate the expression of Runx3 and TGF-β_1 protein in the colon from rats with irritable bowel syndrome(IBS).Methods:Rat model for IBS was established by intracolonic instillation with acetic acid and restraint stress methods,which was confirmed by determinating the visceral sensitivity of the animals,including abdominal withdrawal reflex (AWR) score and the electronic behavior of the abdomen wall.The rats were randomly assigned into three groups:IBS,group(restraint stress,n=25);IBS_2 group(both instillation with acetic acid and restraint stress,n=25) and Control group(n=16).The colonic tissue samples were collected for histological study and the expression of Runx3 and TGF-β_1 proteins were detected by immunohistochemistry.Meanwhile,the relationship of these two proteins was calculated. Results:Visceral hypersensitivity(AWR and abdominal electrical activity) was significantly enhanced in IBS,and IBS_2 groups than other groups.The colon tissue in all groups did not show any signs of inflammation.Furthermore,the expression of Runx3 and TGF-β_1 protein in the colon from all groups show no significant difference(P>0.05),with no remarkable relevancy between each other(P>0.05).Conclusions:The rat model for IBS was successfully established. We did not find any significant changes in the expression of Runx3 and TGF-β_1 protein in the colon tissue from IBS rats,suggesting that the quantitative changes may be not the way by which Runx3 and TGF-β_1 protein play their roles in IBS.The accurate roles of Runx3 and TGF-β_1 proteins in the pathogenesis of IBS remains to be further studied.
基金Supported by Natural Scienee Foundation of Hainan Province(No 30855)
文摘Objective:To investigate the role of Runx3 protein and TGF-β_1 in the pathogenesis of irritable bowel syndrome(IBS),as well as the correlation of these two proteins.Methods:Colonic tissue was collected from patients with IBS and normal persons.The colonic expression of Runx3 protein and TGF-β_1 was detected with immunohislochemistry method.Semi-quantitative analysis was used to evaluate the staining degree of these two proteins.Results:Compared with their counterparts,patients with IBS did not show any changes in the colonic expression of Runx3 protein and TGF-β_1(P>0.05).Interestingly,there was a significant correlation between Runx3 protein and TGF-β_1 in patients with IBS(P<0.05).Conclusions:The role of Runx3 protein and TGF-β_1 in the pathogenesis of IBS remains to be further studied.
文摘A progressive neurodegenerative disease,Alzheimer’s disease(AD).Studies suggest that highly expressed protein isoaspartate methyltransferase 1(PCMT1)in brain tissue.In the current study,we explored the effects of neural stem cell-conditioned medium(NSC-CDM)on the PCMT1/MST1 pathway to alleviate Aβ_(25-35)-induced damage in SH-SY5Y cells.Our data suggested that Aβ_(25-35) markedly inhibited cell viability.NSC-CDM or Neural stem cell-complete medium(NSC-CPM)had a suppression effect on toxicity when treatment with Aβ_(25-35),with a greater effect observed with NSC-CDM.Aβ_(25-35)+NSC-CDM group exhibited an increase in PCMT1 expression.sh-PCMT1 markedly decreased cell proliferation and suppressed the protective role of NSC-CDM through the induction of apoptosis and improved p-MST1 expression.Overexpression of PCMT1 reversed the Aβ_(25-35)-induced decrease in cell proliferation and apoptosis.In summary,our findings suggest that NSC-CDM corrects the Aβ_(25-35)-induced damage to cells by improving PCMT1 expressions,which in turn reduces phosphorylation of MST1.
文摘Background SMAD proteins have recently been identified as the first family of putative transforming growth factor-β_1(TGF-β_1) signal transducers. This study was to investigate the effects of TGF-β_1 and signal protein Smad3 on rat cardiac hypertrophy.Methods The incorporation of [3H]-leucine was measured to determine the hypertrophy of cardiomyocyte incubated with different doses of TGF-β_1 in cultured neonatal cardiomyocytes. The model of rat cardiac hypertrophy was produced with constriction of the abdominal aorta. At different times after the operation, rats were killed, and their left ventricular mass index (LVMI) determined. The mRNA expression of TGF-β_1 and Smad3 of cultured cells and hypertrophic left ventricles were assessed by RT-PCR. The protein expression of Smad3 was assessed by Western blot.Results In cultured neonatal cardiomyocytes, TGF-β_1 significantly promoted incorporation of [3H]-leucine. With the concentration of 3 pg/L, it increased the expression of Smad3 in mRNA and protein levels after 15 minutes, and continued for up to 8 hours of cultured cardiomyocytes. The LVMI and the expression of TGF-β_1 (mRNA) and Smad3 (mRNA and protein) of hypertrophic left ventricle were increased by day 3 after the operation and continued to the 4th week. The peak expression of these was in the second week after operation.Conclusion TGF-β_1 has positive effects on rat cardiomyocyte hypertrophy. Signal protein Smad3 could be related to the pathologic progression of rat cardiac hypertrophy.
基金supported by the National Natural Science Foundation of China(NSFC31430025)the Beijing Advanced Innovation Center for Genomics at Peking Universitythe Peking-Tsinghua Center for Life Sciences。
文摘As the leading cause of worldwide hospital-acquired infection,Clostridioides difficile(C.difficile)infection has caused heavy economic and hospitalized burden,while its pathogenesis is not fully understood.Toxin B(Tcd B)is one of the major virulent factors of C.difficile.Recently,CSPG4 and FZD2 were reported to be the receptors that mediate Tcd B cellular entry.However,genetic ablation of genes encoding these receptors failed to completely block Tcd B entry,implicating the existence of alternative receptor(s)for this toxin.Here,by employing the CRISPR-Cas9 screen in CSPG4-deficient He La cells,we identified LDL receptor-related protein-1(LRP1)as a novel receptor for Tcd B.Knockout of LRP1 in both CSPG4-deficient He La cells and colonic epithelium Caco2 cells conferred cells with increased Tcd B resistance,while LRP1 overexpression sensitized cells to Tcd B at a low concentration.Co-immunoprecipitation assay showed that LRP1 interacts with full-length Tcd B.Moreover,CROPs domain,which is dispensable for Tcd B’s interaction with CSPG4 and FZD2,is sufficient for binding to LRP1.As such,our study provided evidence for a novel mechanism of Tcd B entry and suggested potential therapeutic targets for treating C.difficile infection.
文摘AIM:To investigate the pathway(s)mediating rat antral circular smooth muscle contractile responses to the cholinomimetic agent,bethanechol and the subtypes of muscarinic receptors mediating the cholinergic contraction. METHODS:Circular smooth muscle strips from the antrum of Sprague-Dawley rats were mounted in muscle baths in Krebs buffer.Isometric tension was recorded.Cumulative concentration-response curves were obtained for(+)-cis- dioxolane(cD),a nonspecific muscarinic agonist,at 10^(-8)- 10^(-4)mol/L,in the presence of tetrodotoxin(TTX,10^(-7)mol/L). Results were normalized to cross sectional area.A repeat concentration-response curve was obtained after incubation of the muscle for 90 min with antagonists for M1(pirenzepine), M2(methoctramine)and M3(darifenadn)muscarinic receptor subtypes.The sensitivity to PTX was tested by the ip injection of 100 mg/kg of PTX 5 d before the experiment.The antral circular smooth muscles were removed from PTX-treated and non-treated rats as strips and dispersed smooth muscle cells to identify whether PTX-linked pathway mediated the contractility to bethanechol. RESULTS:A dose-dependent contractile response observed with bethanechol,was not affected by TTx.The pretreatment of rats with pertussis toxin decreased the contraction induced by bethanechol.Lack of calcium as well as the presence of the L-type calcium channel blocker,nifedipine,also inhibited the cholinergic contraction,with a reduction in response from 2.5±0.4 g/mm^2 to 1.2±0.4 g/mm^2(P<0.05).The dose- response curves were shifted to the right by muscarinic antagonists in the following order of affinity:darifenacin (M_3)>methocramine(M_2)>pirenzepine(M_1). CONCLUSION:The muscarinic receptors-dependent contraction of rat antral circular smooth muscles was linked to the signal transduction pathway(s)involving pertussis-toxin sensitive GTP-binding proteins and to extracellular calcium via L-type voltage gated calcium channels.The presence of the residual contractile response after the treatment with nifedipine,suggests that an additional pathway could mediate the cholinergic contraction.The involvement of more than one muscarinic receptor(functionally predominant type 3 over type 2)also suggests more than one pathway mediating the cholinergic contraction in rat antrum.
