Expression of myocyte enhancer factor 2A in processing of hepatic stellate cell activation / 中国病理生理杂志

ABSTRACT

AIM: To observe the changes in expression and activity of the transcription factor myocyte enhancer factor 2A (MEF2A) during hepatic stellate cells (HSC) activation, and to study the roles of MEF2A in the process of HSC activation. METHODS: Cultured HSC was isolated from male sprague-dawley rat liver on plastic dishes and were used as model of activation. The freshly isolated (0 day) and cultured HSC at time points of 1st, 2nd, 3rd, 4th, 5th, 6th, 7th and 8th day were collected. Expression of MEF2A mRNA was detected by real-time quantitative PCR. MEF2A and α-smooth muscle actin (α-SMA, a marker for activated HSC) were tested by Western blotting. Meanwhile, the MEF2A DNA binding activity was determined by electrophoretic mobility shift assays (EMSA). RESULTS: The expression of MEF2A mRNA was small amounts in the freshly isolated HSC and increased gradually after culture on plastic dishes. Western blotting revealed that the freshly isolated HSC expressed very low levels of MEF2A and α-SMA. The proteins of MEF2A and α-SMA were increased gradually in the process of HSC activation. Increased MEF2A protein was correlated with α-SMA. EMSA revealed that MEF2A DNA binding activity was increased gradually during HSC activation. CONCLUSION: In the process of HSC activation, expression and activity of MEF2A are increased gradually, indicating a role in HSC activation.