OBJECTIVETo study whether total saponins of Panax notoginseng (PNS) can prevent renal interstitial fibrosis occurrence through blocking the IL-1alpha induced tubular epithelial cell and decrease the secretion of extracellular matrix (ECM).

METHODSNormal rats' tubular epithelial cells NRK52E were cultured in vitro, their morphological changes were observed by inverted phase contrast microscope and scanning electron microscope. Flow cytometry technique and immuno-histochemical method was used to detect the expression of alpha-smooth muscle actin (alpha-SMA), and ELISA was used to quantitatively detect the fibronectin (FN) in the supernatant

RESULTSIL-1alpha could induce the transdifferentiation of tubular epithelial myofibroblast, showing hypertrophy of cells elongated and fusiform-shaped, with significantly enhanced expression of alpha-SMA and increased secretion of FN (P<0.05). After adding PNS of different concentrations, the morphology of cells restored close to normal tubular epithelial cells, with the increase of alpha-SMA expression and FN secretion significantly inhibited (P<0.05) in dose-dependent manner (P<0.05). But addition of different dosages of PNS alone showed no effect on tubular cells.

CONCLUSIONIL-1alpha could induce the transdifferentiation of tubular epithelial myofibroblast, promote the deposition of ECM component FN. PNS could inhibit IL-1alpha induced the transdifferentiation of NRK52E and secretion of ECM, therefore, PNS could be taken as a new drug for prevention and treatment of renal interstitial fibrosis and terminal stage of renal diseases.