Objective:To investigate the antifibrotic effects of curcumin in a transverse aortic constriction(TAC)mouse model and elucidate its molecular mechanisms.Methods:Male C57BL/6 mice underwent TAC and received vehicle,low...Objective:To investigate the antifibrotic effects of curcumin in a transverse aortic constriction(TAC)mouse model and elucidate its molecular mechanisms.Methods:Male C57BL/6 mice underwent TAC and received vehicle,low-dose curcumin(50 mg/kg),high-dose curcumin(200 mg/kg),high-dose curcumin plus a scrambled control antagomir,or high-dose curcumin plus anti-miR-29b treatments.Cardiac function was assessed by echocardiography.Fibrosis was evaluated by histology,collagen volume fraction,and hydroxyproline content.Expression of miR-29b,HDAC4,and fibrosis-related markers(Col1a1,Col3a1,TGF-β1)was measured by quantitative RT-PCR and Western blotting assays.Myocardial procollagen type I carboxy-terminal propeptide was determined by ELISA,and HDAC4-specific enzymatic activity was assayed using a fluorogenic kit.Results:Curcumin improved cardiac function,reduced fibrosis,restored miR-29b expression,and suppressed HDAC4 expression and activity in a dose-dependent manner.Furthermore,curcumin decreased myocardial procollagen type I carboxy-terminal propeptide levels,confirming reduced collagen synthesis.Anti-miR-29b administration partially abrogated the antifibrotic and cardioprotective effects of curcumin.Conclusions:Curcumin attenuates pressure overload-induced cardiac fibrosis and dysfunction in a TAC mouse model via modulation of the miR-29b/HDAC4 axis and suppression of collagen synthesis.展开更多
Objectives Dysregulated osteoclast function contributes to skeletal diseases.However,the specific ubiquitination regulators of the osteoclastogenesis repressor MafB,particularly at the post-translational level,remain ...Objectives Dysregulated osteoclast function contributes to skeletal diseases.However,the specific ubiquitination regulators of the osteoclastogenesis repressor MafB,particularly at the post-translational level,remain undefined.This study aims to identify ubiquitin-specific proteases(USPs)that deubiquitinate MafB and enhance its stability.Methods We constructed a MafB-conjugated luciferase and overexpressed 40 individual USPs,measuring changes in luciferase activity.The identified USP was overexpressed in human CD14^(+) peripheral blood mononuclear cells(PBMCs)to evaluate its effect.Osteoclast differentiation was assessed through osteoclast marker Integrin alpha-V(CD51)staining and Western blot analysis.Co-immunoprecipitation(co-IP)was performed to assess the interplay.The influence on MafB ubiquitination and degradation was evaluated via immunoprecipitation and Western blot.Finally,MafB was knocked down in the USP-overexpressing PBMCs to analyze its effect on osteoclast differentiation.Results Overexpression of ubiquitin-specific protease 29(USP29)significantly increased MafB expression by approximately 75%(p<0.0001).Elevated USP29 levels strongly inhibited osteoclastic differentiation in CD14^(+) PBMCs(p<0.0001).USP29 was found to interact with MafB,markedly reducing its ubiquitination and subsequent degradation in PBMCs(p<0.001).Knocking down MafB in USP29-overexpressing PBMCs alleviated the inhibitory effect of USP29 on osteoclastogenesis.Conclusion USP29 acts as a potent stabilizer of MafB,inhibiting osteoclastogenesis in human CD14^(+) PBMCs,at least in part,by enhancing MafB stability.These findings expand our understanding of USP29’s role and the post-translational regulation of MafB.Furthermore,USP29 serves as a vital factor that controls osteoclast differentiation,and its regulatory function is at least partially mediated by deubiquitinating and stabilizing MafB.展开更多
基金supported by China International Medical Foundation(Z-2019-42-1908-4)Natural Science Basic Research Program of Shaanxi Province(2019JM-440).
文摘Objective:To investigate the antifibrotic effects of curcumin in a transverse aortic constriction(TAC)mouse model and elucidate its molecular mechanisms.Methods:Male C57BL/6 mice underwent TAC and received vehicle,low-dose curcumin(50 mg/kg),high-dose curcumin(200 mg/kg),high-dose curcumin plus a scrambled control antagomir,or high-dose curcumin plus anti-miR-29b treatments.Cardiac function was assessed by echocardiography.Fibrosis was evaluated by histology,collagen volume fraction,and hydroxyproline content.Expression of miR-29b,HDAC4,and fibrosis-related markers(Col1a1,Col3a1,TGF-β1)was measured by quantitative RT-PCR and Western blotting assays.Myocardial procollagen type I carboxy-terminal propeptide was determined by ELISA,and HDAC4-specific enzymatic activity was assayed using a fluorogenic kit.Results:Curcumin improved cardiac function,reduced fibrosis,restored miR-29b expression,and suppressed HDAC4 expression and activity in a dose-dependent manner.Furthermore,curcumin decreased myocardial procollagen type I carboxy-terminal propeptide levels,confirming reduced collagen synthesis.Anti-miR-29b administration partially abrogated the antifibrotic and cardioprotective effects of curcumin.Conclusions:Curcumin attenuates pressure overload-induced cardiac fibrosis and dysfunction in a TAC mouse model via modulation of the miR-29b/HDAC4 axis and suppression of collagen synthesis.
文摘Objectives Dysregulated osteoclast function contributes to skeletal diseases.However,the specific ubiquitination regulators of the osteoclastogenesis repressor MafB,particularly at the post-translational level,remain undefined.This study aims to identify ubiquitin-specific proteases(USPs)that deubiquitinate MafB and enhance its stability.Methods We constructed a MafB-conjugated luciferase and overexpressed 40 individual USPs,measuring changes in luciferase activity.The identified USP was overexpressed in human CD14^(+) peripheral blood mononuclear cells(PBMCs)to evaluate its effect.Osteoclast differentiation was assessed through osteoclast marker Integrin alpha-V(CD51)staining and Western blot analysis.Co-immunoprecipitation(co-IP)was performed to assess the interplay.The influence on MafB ubiquitination and degradation was evaluated via immunoprecipitation and Western blot.Finally,MafB was knocked down in the USP-overexpressing PBMCs to analyze its effect on osteoclast differentiation.Results Overexpression of ubiquitin-specific protease 29(USP29)significantly increased MafB expression by approximately 75%(p<0.0001).Elevated USP29 levels strongly inhibited osteoclastic differentiation in CD14^(+) PBMCs(p<0.0001).USP29 was found to interact with MafB,markedly reducing its ubiquitination and subsequent degradation in PBMCs(p<0.001).Knocking down MafB in USP29-overexpressing PBMCs alleviated the inhibitory effect of USP29 on osteoclastogenesis.Conclusion USP29 acts as a potent stabilizer of MafB,inhibiting osteoclastogenesis in human CD14^(+) PBMCs,at least in part,by enhancing MafB stability.These findings expand our understanding of USP29’s role and the post-translational regulation of MafB.Furthermore,USP29 serves as a vital factor that controls osteoclast differentiation,and its regulatory function is at least partially mediated by deubiquitinating and stabilizing MafB.
