SUN-155 PROTECTIVE ROLES OF TRIGONELLINE AGAINST OXALATE-INDUCED EPITHELIAL-TO-MESENCHYMAL TRANSITION IN RENAL TUBULAR EPITHELIAL CELLS

Abstract

Fibrogenesis is a common feature for all types of chronic kidney disease (CKD). Epithelial-to-mesenchymal transition (EMT) of renal tubular epithelial cells is one of the main processes involving renal fibrosis and its inhibition is thus considered as a preventive/therapeutic strategy for CKD. Trigonelline (TRIG), a plant alkaloid commonly found in herbs, coffee bean, soy bean and other edible food plants, has several beneficial effects on human health and has been proposed to reduce renal fibrosis but with unclear mechanisms. This study thus addressed cellular mechanism underlying the anti-fibrogenic effects of TRIG in renal tubular epithelial cells. MDCK renal tubular cells were pretreated with or without 100 µM TRIG for 2 h followed by treatment with 0.5 mM sodium oxalate for 24 h. The cells were then subjected to cell death assay, cell proliferation assay, morphological study, immunofluorescence staining, gelatin zymogram assay, cell migration assay, and measurement of intracellular reactive oxygen species (ROS). EMT was successfully induced by oxalate treatment as indicated by morphological changes into spindle-shape cells, increased expression of mesenchymal proteins (fibronectin, vimentin and α-smooth muscle actin (α-SMA)), decreased expression of epithelial proteins (E-cadherin and zonula occludens-1 (ZO-1)) and increased activity of a profibrotic factor (matrix metalloproteinase-9 (MMP-9)). Interestingly, these oxalate-induced EMT features could be attenuated by TRIG pretreatment. Moreover, TRIG also prevented oxalate-induced cell migration, ROS overproduction, and down-regulation of Nrf-2 signaling molecule. These data indicated that TRIG could attenuate the effects of oxalate-induced EMT and thus may serve as the anti-fibrotic compound for prevention and/or treatment of CKD.