Hcmv-miR-UL112 And Mcmv-miR-m01-2 Target ACE2 To Participate In The Regulation Of Blood Pressure

Background Studies have shown that the infection of mouse cytomegalovirus(MCMV)causes an elevation in arterial blood pressure in mouse,suggesting that CMV may play important roles in the regulation of hypertension and cardiovascular disease.Human cytomegalovirus(HCMV)is a ubiquitous pathogen.A recent study from Jun Cai and Xinchun Yang's research group demonstrated that the serum level of hcmv-miR-ULl 12,a miRNA derived from HCMV,was 2-fold higher in the serum of essential hypertensive patients as compared with that of the healthy volunteers.Interestingly,in a previous study analyzing the roles of miRNAs in osmotic regulation in kidney cells,we found that mIMCD3 cells subjected to a 2-h hypertonicity treatment,the expression of mcmv-miR-m01-2 increased by approximately 3 folds in comparision with the control cells,indicating CMV miRNAs might be significantly induced by some external stimulus.Although the causal roles of CMV infection in inducing high blood pressues were largely established,the underlying mechanisms were unclear.In this study,we investigated the regulation of a few hypertension-related genes by hcmv-miR-UL112 or mcmv-miR-m01-2 in the cultured renal cells.Meanwhile,we performed in vivo experiments investigating hcmv-miR-UL112's impacts on the body's blood pressure in mice.Methodology Through overexpression of mcmv-miR-m01-2 or hcmv-miR-UL112 in mIMCD3 and HEK293T cells,we examined how they affected the expression of ACE2 and certain other hypertension related genes.The in vivo overexpression of hcmv-miR-UL112 was induced by tail vein injection of lentivirus carrying a minigene encoding hcmv-miR-UL112 to eight-week old wild-type male C57BL/6 mice.Renal tissues expression of hcmv-miR-UL112 and ACE2 mRNA and protein expression,and the blood pressure was analyzed for the hcmv-miR-UL112-overexpressed mice and the control-lentivirus injected mice.Results Overexpression of mcmv-miR-m01-2 or hcmv-miR-UL112 significantly suppressed the expression of ACE2 in mIMCD3 cells.Meanwhile,the overexpression of hcmv-miR-UL112 also inhibited the ACE2 expression in HEK293T cells.Moreover,increased mcmv-miR-m01-2 or hcmv-miR-UL112 greatly suppressed the luciferase reproter activity of ACE2-3'UTR in mIMCD3 cells,whereas disruption of the miRNA-3'UTR interactions abrogated the silencing effects of miRNAs.Similarly,the luciferase activity assay showed that hcmv-miR-UL112 targeted ACE2 also through its interaction with ACE2-3'UTR in HEK293T.In vivo,the blood pressure of hcmv-miR-UL112-overexpressed mice was higher than that of control-lentivirus injected mice.Conclusion mcmv-miR-m01-2 or hcmv-miR-UL 112 is capable of negatively regulating ACE2 gene expression in renal tissues,resulting in alterations in the renin angiotensin system(RAS)signaling and blood pressure.These results demonstrate that CMV infection medaites the elevation of blood pressure in part through mcmv-miR-m01-2 or hcmv-miR-UL112 meidated repression of ACE2.