Protective effect of ginsenoside Rb1 against tacrolimus-induced apoptosis in renal proximal tubular LLC-PK1 cells

Abstract Background The aim of the present study was to evaluate the potential protective effects of six ginsenosides(Rb1, Rb2, Rc, Rd, Rg1, and Rg3) isolated from Panax ginseng against tacrolimus(FK506)-induced apoptosis in renal proximal tubular LLC-PK1 cells. Methods LLC-PK1 cells were treated with FK506 and ginsenosides, and cell viability was measured. Protein expressions of mitogen-activated protein kinases, caspase-3, and kidney injury molecule-1 (KIM-1) were evaluated by Western blotting analyses. The number of apoptotic cells was measured using an image-based cytometric assay. Results Reduction in cell viability by 60μM FK506 was ameliorated significantly by cotreatment with ginsenosides Rg1and Rb1. The phosphorylation of p38, extracellular signal-regulated kinases, and KIM-1, and cleavage of caspase-3, increased markedly in LLC-PK1 cells treated with FK506 and significantly decreased after cotreatment with ginsenosideRb1. The number of apoptotic cells decreased by 6.0% after cotreatment with ginsenosideRb1 (10μM and 50μM). Conclusion The antiapoptotic effects of ginsenosideRb1 on FK506-induced apoptosis were mediated by the inhibition of mitogen-activated protein kinasesand caspase activation.