Effect Of Modified Huangqi Chifeng Decoction On Renal Fibrosis Based On TGF - β <1> / Smad Signaling Pathway

Research Background:Renal fibrosis is the common pathway when all the chronic kidney diseases develop to the end. The main pathology acts as:normal rental units are replaced by a large number of fibroblasts and myofibroblast proliferation. The production and accumulation of extracellular matrix, such as collagen fibers and the fibronectin, leads to the glomerular sclerosis, the renal interstittium fibrosis, and the loss of renal function finally. In the development of renal fibrosis, many cells growth factors are directly or indirectly involved. Transforming growth factor-β1 (TGF-β1) is widely recognized as the key factor of renal fibrosis and Smad proteins is the key of TGF-β1 signaling pathway downstream medium, thus TGF-β1/Smad signaling pathway plays an important role in the development of the renal fibrosis. Currently a lot of researches of TCM intervention about renal fibrosis are focusing on the TGF-β1/Smad signaling pathway, and the key to the prevention and cure of the renal fibrosis is the effective intervention of the signal transduction of TGF-β1/Smad signaling pathway. Modified Huangqichifeng Decoction (MHD) is a commonly used formula for treating chronic nephritis by Zhang Yu. and has achieved good clinical effect. The preliminary research on MHD for the prevention of renal fibrosis was conducted. It was found that the MHD medicated serum can inhibit the proliferation of mesangial cells in mice induced by LPS. and significantly promote the apoptosis of mouse mesangial cells. This research is based on the TGF-β1/Smad signaling pathway to study the mechanism of MHD anti-renal fibrosis.Objective:To observe the effects of Modified Huangqichifeng Decoction (MHD) on TGF-β1/Smad signaling pathways, and study the mechanism of MHD anti-renal fibrosis.Methods:① Adopting the serum pharmacology method, the medicated serum was prepared using rats fed with Modified Huangqichifeng Decoction (MHD) or telmisartan.② Mouse mesangial cells were cultured under vitro condition using Lipopolysaccharides (LPS) as a stimulating factor. After mouse mesangial cells were intervened by medicated serum, the cells were divided into six groups:the normal group, the model group, the telmisartan group, the MHD groups with high, medium and low dose. ③ The cell supernatants in each group were collected after mouse mesangial cells were intervened for 72 h by medicated serum. The content of LN and FN were measured using Enzyme-linked immunoassay adsorption test method (ELISA). ④ Expression of TGF-(β1, p-Smad2/3, Smad7. and CTGF proteins were detected by using the western-blot method.Results:1. Compared with the normal group. the expressions of LN and FN in the supernatant of other groups were significantly increased after mesangial cells were stimulated for 72h by LPS (P<0.01). Compared with the model group, the expression of LN in the telmisartan group and the MHD group with medium dose were significantly reduced (P<0.05). ③ Compared with the model group, the expression of FN in the telmisartan group, the MHD group with medium dose or low dose were significantly reduced (P<0.01).2. Compared with the normal group, the protein expressions of TGF-β1, p-Smad2/3 and CTGF were significantly increased in the model group (P<0.01), while the Smad7 protein expression was significantly reduced in the model group (P<0.01). ② Compared with the model group, the protein expressions of TGF-β1 in telmisartan group and the MHD groups with each dose were significantly reduced (P<0.01 or P<0.05).The difference between the MHD groups with each dose were statistically significant (P<0.01 or P<0.05). ③Compared with the model group, the protein expressions of p-Smad2/3 in the telmisartan group and the MHD groups with each dose were significantly reduced (P<0.01 or P<0.05). ④ The Smad7 protein expressions in the MHD group with high or medium dose were significantly increased compared with the model group (P<0.05). ⑤Compared with the model group, the protein expressions of CTGF in the telmisartan group, MHD group with high dose or medium dose were significantly reduced (P<0.01), and the CTGF protein expression in the MHD group with low dose was decreased (P<0.05).the difference of the CTGF protein expressions between the telmisartan group and the MHD group with medium dose was statistically significant (P<0.05).Conclusion:Modified Huangqichifeng Decoction (MHD) can inhibit the increasing secretion of extracellular matrix of the glomerular mesangial cells induced by inflammatory factors, and inhibit the excessive activation of TGF-β1/Smad signaling pathways of the glomerular mesangial cells. This may be one of the anti-renal fibrosis mechanisms of MHD.