Cytokines Promote Glomerular Mesangial Cell Survival in Vitro by Stimulus-Dependent Inhibition of Apoptosis

Abstract

Resolution of glomerular inflammation requires the removal of proliferating resident glomerular mesangial cells, but excessive loss of glomerular cells is a feature of postinflammatory scarring. Because apoptosis regulates mesangial cell number in glomerular inflammation, we have studied the exogenous control of apoptosis triggered in cultured mesangial cells by stimuli likely to be important in vivo. Apoptosis could be induced by serum deprivation to model decreased availability of survival factors, by etoposide as an example of DNA-damaging agents, by ligation of mesangial cell Fas, and by protein synthesis inhibition by cycloheximide. Insulin-like growth factor I (IGF-I), IGF-II, and basi..