Protective effects of polyphenols against cadmium-induced glomerular mesangial cell myocontracture

The main objective of this work was to determine the ability of polyphenols (procyanidoloic oligomers; PCO) to diminish the contracture of CdCl2-induc ed mesangial cells (smooth muscle cell type). Glomeruli were isolated by pa ssing rat renal cortex pulp through calibrated sieves followed by a culture step for outgrowth of cells. PCO lethality was measured by microassay (Neu tral Red uptake). This study has revealed an absence of PCO toxicity during exposure for 24 h and for concentrations ranging from 0.031 to 1 parts per thousand (w/v) on rat renal mesangial cells. We observed a lack of cytotox icity response for the PCO mixture dissolved in medium. Quantitative assess ments of the planar cell surface area (PCSA) were performed with an accurat e automatized image analyser. The use of isolated cultured mesangial cells permits us to evaluate by quantitative morphometric analysis the contractur e elicited either with CdCl2 salts alone or by previous incubation with a n on-lethal dose of PCO. When renal mesangial cells were exposed for 10 min t o the PCO mixture, the Cd-mediated myocontracturant response of the mesangi al cells was totally abolished. These results suggest that polyphenols coul d be effective against renal damages induced by cadmium.