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.