The study of genome DNA methylation in rheumatoid arthritis / 中华风湿病学杂志

ABSTRACT

Objective To study the genome DNA methylation in rheumatoid arthirits(RA)and the re- lated factors of DNA methylation.Methods Twenty-first cases with RA and 20 controls were recruited to par- ticipate the study.Plasma Hcy,SAM,SAH,the MTHFR gene C677T polymorphism and the expression of LFA-1 in CD4~+T cells was measured in all patients and controls.Results①The SAM levels were lower sig- nificantly in RA groups than in controls.The SAH levels were higher significantly in RA groups than in con- trols.②There was significant inverse correlation between plasma Hcy level and SAM level(r=-0.932,P＜0.01). There was significant positive correlation between plasma Hcy level and SAH level(r=0.924,P＜0.01).③The expression of LFA-1 in CD4~+T cells was higher significantly in RA groups than in controls.There was a signif- icant positive correlation between LFA-1 expression level and Hcy level(r=0.557,P＜0.01),a significant in- verse correlation between LFA-1 expression level and SAM level(r=-0.651,P＜0.01).④The MTHFR gene mu- tation lead to dramatically increase of Hcy,SAH level and the expression of LFA-1 level in CD4~+T cells and genome DNA hypomethylation.Conclusion①Hypomethylation of genome DNA is found in most RA pa- tients.②The factors associated with genome DNA hypomethylation include MTHFR gene mutation and hyper- homocysteinemia.③The expression of LFA-1 in CD4~+ T cells is higer in RA groups than in controls,which re- lates to the DNA methylation level and the MTHFR gene C677T polymorphism.