Overexpression of megsin induces mesangial cell proliferation and excretion of type IV collagen in vitro.

Over-expression of megsin is associated with mesangial cell (MC) proliferation and extracellular matrix (ECM) accumulation. The underlying pathogenesis is unknown. This study demonstrate that over-expression of megsin induced incorporation of [(3)H]thymidine in MCs and PDGF-BB, TGF-β1 upregulation. Concentrations of PDGF-BB, TGF-β1 and type IV collagen in the culture medium of MCs transfected with megsin were higher than controls. Anti-PDGF-BB suppressed incorporation of [(3)H]thymidine in MCs transfected with megsin and mRNA expression of TGF-β1 in stable transformant MCs, suggesting that over-expression of megsin induces cell proliferation and ECM accumulation in MCs, upregulation of PDGF-BB and TGF-β1 is probably the main route involved in pathogenesis.