Effects on Proliferation and Secretion of Extracellular Matrix of Rat Glomerular Mesangial Cell Induced by Lipopolysaccharide

Objective To observe the effects of Lipopolysaccharide (LPS) on proliferation and secretion of extracellular matrix (ECM) of rat glomerular mesangial cells.Methods The cultured glomerular mesangial cells (GMC) of rat in vitro were established,and used for experiment after identification.Two groups divided in the experiment were control group and LPS induced (LPS) group.GMC proliferation was detected by MTT (methyl thiazolyl tetrazolium) incorporation method at 24h and 48h.The contents of ECM protein secretion at 6h,12h and 48h were detected by the enzyme-linked immunosorbent-assay (ELISA).The changes of laminin (LN)β2 mRNA expression were detected by semi-quantitative real-time RT-PCR.Results (1) There was significant difference in mesangial cell proliferation between the LPS and control group (P0.05).(2) Mesangial cells can secrete some ECM proteins in normally cultured medium.Mesangial cell secreted much more ECM protein in LPS group than that in control group,with a significant difference (P0.01).(3) Mesangial cell can express LNβ2 mRNA in normally cultured medium.LNβ2 mRNA expression was much higher in LPS group than that in control group at all time points,and the difference was significant (P0.01)..Conclusion LPS can induce the proliferation of mesangial cell and increase the secretion of the ECM (including LN,fibronectin and type IV collagen) at the mRNA and protein levels.This shows that ECM plays a major role in membranoproliferative glomerulonephritis.