Effects of Tridocosahexaenoyl-Glycerol Emulsion on Proteinuria in Rats with Nephrotoxic Serum Nephritis

BACKGROUND Docosahexaenoic acid (DHA) is one of the n-3 polyunsaturated fatty acids and an important component of cell membrane phospholipids (PL). Nephrotoxic serum (NTS) nephritis was a worldwide model of the Goodpasture syndrome. We investigated the effects of tridocosahexaenoyl-glycerol (DHA-TG) emulsion on proteinuria in rats with NTS nephritis. METHODS Sixteen male Wistar rats weighing approximately 200 g were used. Twelve rats were treated with NTS via the tail vein and divided into 3 groups (groups A, B, and C). Another 4 rats treated with saline served as controls (group D). DHA-TG and soybean oil emulsions were intraperitoneally administered to the rats in groups A and B, respectively, 24 h prior to NTS injection, and 0, 1, 2, 3, 4, and 5 days after the injection. Saline was administered to the rats in groups C and D in the same manner. All rats were sacrificed on day 6 to obtain plasma and kidney samples. Analyses of urinary protein levels and fatty acid composition of plasma and kidney as well as histological examination of the kidneys were performed. RESULTS Urinary protein levels in group A were significantly lower than those in group C (35.0 ± 13.3 vs. 79.2 ± 11.8 mg/day on day 5, means ± SE, p < 0.05). DHA levels in the PL fraction of the kidneys in group A were significantly increased compared with those in groups B and C. CONCLUSIONS These results suggest that the DHA-TG emulsion may have beneficial effects on NTS nephritis in the rat.