Protective effects of proanthocyanidin and vitamin E against toxic effects of formaldehyde in kidney tissue.

We investigated possible effects of proanthocyanidin (PA) and vitamin E on damage to rat kidneys induced by formaldehyde (FA), using biochemical characteristics and light and electron microscopy. Male rats were divided into control, FA, PA and vitamin E treated groups. Kidney tissue was observed by light and electron microscopy. Bcl-2/Bax rate was measured using immunohistochemistry. Malondialdehyde (MDA) and total sialic acid (TSA) levels, superoxide dismutase (SOD), glutathione peroxidase (Gpx), catalase (CAT) and myeloperoxidase (MPO) activities were measured. We found that FA caused damage to the parietal epithelial layer of the glomerulus, mononuclear cell infiltration, membrane damage in renal tubules, pyknotic nuclei, hypertrophic cells in Henle's loop and tubules, and loss of renal tubule integrity. We also observed invagination of the nuclear membrane, irregularity of chromatin material and loss of mitochondrial cristae. We observed increased Bcl-2 and Bax immunostaining in the FA group, but the Bcl-2/Bax rate remained unchanged in FA, PA and vitamin E groups compared to controls. Tissue MDA and TSA levels, and CAT and Gpx activities were increased, and SOD and MPO activities were decreased by FA toxicity. We observed a protective effect of PA in tissue MDA and TSA levels and SOD activities, because there was no difference in the PA group compared to the control group. We investigated the antioxidant effects of PA and vitamin E and found protective effects of PA against apoptosis.