TGF-?1 upregulates Smad2 expression in peritoneal mesothelial cells / 中国病理生理杂志

ABSTRACT

AIM: To investigate the expression of Smad2 signal protein in peritoneal mesothelial cells and how transforming growth factor ?1 (TGF-?1) affects its expression. METHODS: Rat peritoneal mesothelial cells were cultured in different levels of TGF-?1 (0,1.25,2.5,10 ?g/L) for different time (0,5,15,30,60,120 min). Endogenous Smad2 expression was evaluated by RT-PCR and immunohistochemical assay. The alteration of subcellular location of Smad2 was determined by immunohistochemical assay. RESULTS: TGF-?1 induced Smad2 mRNA expression, which increased at 5 min, peaked at 30 min, and declined to baseline levels by 120 min, in a time-dependent manner. Smad2 mRNA expression induced by TGF-?1 was also in a dose -dependent manner. TGF-?1 induced Smad2 phosphorlylation and nuclear localization in both time-dependent and dose-dependent manner, which was concordant with mRNA expression. Smad2 translocated from cytoplasm to nuclear accumulation in response to TGF-?1, and peaked at 30 min. CONCLUSIONS: Smad2 is present in peritoneal mesothelial cells. TGF-?1 may activate Smad2 expression and translocation to nuclear in a time-dependent and dose-dependent manner. [