Cellular microRNAs(miRNAs) have been shown to modulate HCV infection via directly acting on the viral genome or indirectly through targeting the virus-associated host factors. Recently we generated a comprehensive map...Cellular microRNAs(miRNAs) have been shown to modulate HCV infection via directly acting on the viral genome or indirectly through targeting the virus-associated host factors. Recently we generated a comprehensive map of HCV–miRNA interactions through genome-wide miRNA functional screens and transcriptomics analyses. Many previously unappreciated cellular miRNAs were identified to be involved in HCV infection, including miR-135a, a human cancerrelated miRNA. In the present study, we investigated the role of miR-135a in regulating HCV life cycle and showed that it preferentially enhances viral genome replication. Bioinformatics-based integrative analyses and subsequent functional assays revealed three antiviral host factors, including receptor interacting serine/threonine kinase 2(RIPK2), myeloid differentiation primary response 88(MYD88), and C-X-C motif chemokine ligand 12(CXCL12), as bona fide targets of miR-135a. These genes have been shown to inhibit HCV infection at the RNA replication stage. Our data demonstrated that repression of key host restriction factors mediated the proviral effect of miR-135a on HCV propagation. In addition,miR-135a hepatic abundance is upregulated by HCV infection in both cultured hepatocytes and human liver, likely mediating a more favorable environment for viral replication and possibly contributing to HCV-induced liver malignancy.These results provide novel insights into HCV–host interactions and unveil molecular pathways linking miRNA biology to HCV pathogenesis.展开更多
Objective:Myocardial infarction(MI)remains the leading cause of morbidity and mortality due partly to the limited regenerative capacity of cardiomyocytes to replace cardiomyocyte lost due to apoptosis.Inhibiting cardi...Objective:Myocardial infarction(MI)remains the leading cause of morbidity and mortality due partly to the limited regenerative capacity of cardiomyocytes to replace cardiomyocyte lost due to apoptosis.Inhibiting cardiomyocyte apoptosis is recognized as an effective therapeutic approach for MI.MicroRNAs(miRNAs,miRs),which regulate target genes at the post-transcriptional level,play a significant role in the regulation of cardiovascular diseases such as MI.MicroRNA-135b(miR-135b)has a protective effect on cardiomyocytes.However,the role of miR-135b in cardiomyocyte apoptosis in infarct myocardium needs further clarification.Methods:We generatedα-MHC-miR-135b transgenic mice to investigate the role of miR-135b in myocardial injury after MI.MiR-135b mimic and negative control(NC)were transfected into H2O2-induced cardiomyocytes to evaluate the effect of overexpression of miR-135b on the levels of reactive oxygen species(ROS)and apoptosis.Results:Our results showed that overexpression of miR-135b had protective effect on cardiomyocyte injury both in vivo and in vitro.MiR-135b inhibited cardiomyocyte apoptosis and ROS generation,downregulated pro-apoptosis proteins(cleaved-caspase-3 and Bax),and increased anti-apoptosis protein(Bcl-2).Moreover,miR-135b showed an inhibitory effect on apoptosis-related protein target transient receptor potential vanilloid-type 4(TRPV4)cation channel.Conclusion:MiR-135b might be considered a new molecular target for potential replacement therapy as antiapoptotic cardioprotection in the setting of MI.展开更多
基金supported by the Intramural Research Program of the National Institute of Diabetes and Digestive and Kidney Diseases, US National Institutes of Health
文摘Cellular microRNAs(miRNAs) have been shown to modulate HCV infection via directly acting on the viral genome or indirectly through targeting the virus-associated host factors. Recently we generated a comprehensive map of HCV–miRNA interactions through genome-wide miRNA functional screens and transcriptomics analyses. Many previously unappreciated cellular miRNAs were identified to be involved in HCV infection, including miR-135a, a human cancerrelated miRNA. In the present study, we investigated the role of miR-135a in regulating HCV life cycle and showed that it preferentially enhances viral genome replication. Bioinformatics-based integrative analyses and subsequent functional assays revealed three antiviral host factors, including receptor interacting serine/threonine kinase 2(RIPK2), myeloid differentiation primary response 88(MYD88), and C-X-C motif chemokine ligand 12(CXCL12), as bona fide targets of miR-135a. These genes have been shown to inhibit HCV infection at the RNA replication stage. Our data demonstrated that repression of key host restriction factors mediated the proviral effect of miR-135a on HCV propagation. In addition,miR-135a hepatic abundance is upregulated by HCV infection in both cultured hepatocytes and human liver, likely mediating a more favorable environment for viral replication and possibly contributing to HCV-induced liver malignancy.These results provide novel insights into HCV–host interactions and unveil molecular pathways linking miRNA biology to HCV pathogenesis.
基金supported by CAMS Innovation Fund for Medical Sciences of China(2019-I2M-5-078)National Natural Science Foundation of China(Grant No.81861128022)Natural Science Foundation of Heilongjiang Province(Grant No.LH2019H003).
文摘Objective:Myocardial infarction(MI)remains the leading cause of morbidity and mortality due partly to the limited regenerative capacity of cardiomyocytes to replace cardiomyocyte lost due to apoptosis.Inhibiting cardiomyocyte apoptosis is recognized as an effective therapeutic approach for MI.MicroRNAs(miRNAs,miRs),which regulate target genes at the post-transcriptional level,play a significant role in the regulation of cardiovascular diseases such as MI.MicroRNA-135b(miR-135b)has a protective effect on cardiomyocytes.However,the role of miR-135b in cardiomyocyte apoptosis in infarct myocardium needs further clarification.Methods:We generatedα-MHC-miR-135b transgenic mice to investigate the role of miR-135b in myocardial injury after MI.MiR-135b mimic and negative control(NC)were transfected into H2O2-induced cardiomyocytes to evaluate the effect of overexpression of miR-135b on the levels of reactive oxygen species(ROS)and apoptosis.Results:Our results showed that overexpression of miR-135b had protective effect on cardiomyocyte injury both in vivo and in vitro.MiR-135b inhibited cardiomyocyte apoptosis and ROS generation,downregulated pro-apoptosis proteins(cleaved-caspase-3 and Bax),and increased anti-apoptosis protein(Bcl-2).Moreover,miR-135b showed an inhibitory effect on apoptosis-related protein target transient receptor potential vanilloid-type 4(TRPV4)cation channel.Conclusion:MiR-135b might be considered a new molecular target for potential replacement therapy as antiapoptotic cardioprotection in the setting of MI.
