Role of homocysteine to promote the vascular smooth muscle cell proliferation by MiR-125 b methylation
10.3969/j.issn.1001-1978.2015.07.027
- VernacularTitle:miR-125 b甲基化在同型半胱氨酸促进血管平滑肌细胞增殖中的作用
- Author:
Xianmei LIU
;
Chengjian CAO
;
Jue TIAN
;
Li ZHAO
;
Fanqi KONG
;
Longxia ZHOU
;
Jiukai CHEN
;
Yanhua WANG
;
Xiaoling YANG
;
Yuexia JIA
;
Yideng JIANG
- Publication Type:Journal Article
- Keywords:
homocysteine;
miR-125 b;
DNA methyla-tion;
vascular smooth muscle cell;
atherosclerosis;
proliferation
- From:
Chinese Pharmacological Bulletin
2015;(7):1023-1027
- CountryChina
- Language:Chinese
-
Abstract:
Aim To investigate the role of miR-125 b and its DNA methylation in homocysteine ( Hcy )-in-duced vascular smooth muscle cells( VSMCs) prolifera-tion. Methods VSMCs were stimulated with 0,50, 100, 200, 500 μmol · L-1 Hcy respectively. Then qRT-PCR was used to detect the mRNA levels of miR-125b,and nested-touchdown methylation-specific PCR ( ntMS-PCR) was used to detect the methylation levels of miR-125b. VSMCs were transfected with miR-125b precursor or the inhibitor of miR-125b ,then 3-(4,5-dimethylthiazol-2-yl)-2-5-diphenyl tetrazolium bromide ( MTT ) assay was used to reflect the proliferation of VSMCs. The distribution of CpG islands of miR-125b promoter region was analyzed by bioinformatics meth-ods. VSMCs were stimulated with 100 μmol·L-1 Hcy and transfected with or without DNA methylation inhib-itors 5-nitrogen impurity cytidine ( AZC) , then the ex-pression of miR-125b was detected by qRT-PCR. Re-sults The mRNA levels of miR-125 b were decreased in 100,200,500 μmol·L-1 Hcy group compared with 0 μmol·L-1 Hcy group. The precursor of miR-125b could inhibit the proliferation activity and the inhibitor of miR-125 b could increase the proliferation activity of VSMCs cells. Bioinformatics analysis indicated that MiR-125 b promoter region had a CpG island whose length was 792 bp ( 1881-2672 ) . The miR-125 b pro-moter region methylation levels increased after Hcy in-tervention ( P <0. 01 ) . The expression level of miR-125 b increased after AZC intervention ( P <0. 05 ) . Conclusions ① Hcy promotes vascular smooth mus-cle cell proliferation maybe by down-regulating the ex-pression of miR-125b. ② Hcy down-regulates the ex-pression of miR-125 maybe by up-regulating the methy-lation levels of miR-125b promoter region.
