The aqueous extract of Lycopus lucidus Turcz exerts protective effects on podocytes injury of diabetic nephropathy via inhibiting TGF-β1 signal pathway.

Diabetic nephropathy (DN) is known as a major microvascular complication leading cause of end-stage renal disease, it generally followed by the process of podocyte fragmentation and detachment. Transforming growth factor β1 (TGF-β1) signaling pathway plays a pivotal role in the initiation and progression of DN. In present study, we aim to investigate the effect of lycopus extracts on podocytes injury and TGF-β signaling. In present study, lycopus extracts treatment abolished the gain in blood glucose and body weight in a dose dependent manner and possessed protective effect on the renal damage, which was indicated by the decreased concentration of Scr, BUN and urine creatinine of serum. Histopathological examination also demonstrated lycopus extracts exert protective effect on renal damage. Western blotting and immunohistochemical results revealed lycopus extracts treatment upregulated the expression of nephrin and down-regulated the expression levels of TGF-β1 and Smad4. Moreover, lycopus extracts treatment suppressed TGF-β1-induced phosphorylation of Smad2/3, ERK1/2 and p38 both in vivo and vitro. In conclusion, lycopus extracts is a novel agent that ameliorate podocytes injury by inhibiting TGF-β signaling pathway and possess potential therapeutic effect on renal damage of DN rats.