OBJECTIVE: To explore the expressions of transforming growth factor-beta1 (TGF-beta1) and its signaling transduction molecule Smad 2 and their significance in the development of glomerulosclerosis. METHODS: Using in situ hybridization and immunohistochemistry to detect Smad 2 mRNA expression and TGF-beta1, collagen IV, fibronectin expression in renal biopsies from 61 cases with a spectrum of glomerulonephritis including IgA nephropathy (40 cases), membranous glomerulonephritis (10 cases) and sclerosing glomerulonephritis (11 cases), compared with 11 cases of glomerular mild lesion with image analysis system. RESULTS: With the exception of Smad 2 mRNA expression in mild type IgA nephropathy, all other types of diseased glomeruli showed increased expression of both TGF-beta1 and Smad 2 mRNA when compared with the 11 cases of mild glomerular lesions. The expressions of glomerular TGF-beta1 and Smad 2 mRNA positively correlated with collagen IV and fibronectin deposition in the glomeruli. CONCLUSIONS: TGF-beta1 and Smad 2 may be involved in the excessive deposition of glomerular extracellular matrix and play an important role in the development of glomerulosclerosis.
OBJECTIVE: To explore the expressions of transforming growth factor-beta1 (TGF-beta1) and its signaling transduction molecule Smad 2 and their significance in the development of glomerulosclerosis. METHODS: Using in situ hybridization and immunohistochemistry to detect Smad 2 mRNA expression and TGF-beta1, collagen IV, fibronectin expression in renal biopsies from 61 cases with a spectrum of glomerulonephritis including IgA nephropathy (40 cases), membranous glomerulonephritis (10 cases) and sclerosing glomerulonephritis (11 cases), compared with 11 cases of glomerular mild lesion with image analysis system. RESULTS: With the exception of Smad 2 mRNA expression in mild type IgA nephropathy, all other types of diseased glomeruli showed increased expression of both TGF-beta1 and Smad 2 mRNA when compared with the 11 cases of mild glomerular lesions. The expressions of glomerular TGF-beta1 and Smad 2 mRNA positively correlated with collagen IV and fibronectin deposition in the glomeruli. CONCLUSIONS:TGF-beta1 and Smad 2 may be involved in the excessive deposition of glomerular extracellular matrix and play an important role in the development of glomerulosclerosis.