RESUMO
PURPOSE: A diet with polyunsaturated fatty acid (PUFA) supplementation has been reported to reduce renal and cardiac diseases. This study sought to elucidate whether PUFAs derived from plant or marine oils could have beneficial effects on the progression of experimental chronic renal failure (CRF). METHODS: Experimental CRF was achieved by a 5/6 nephrectomy model. Male Wistar rats were divided into groups and given daily supplements of fish oil (group FO), flaxseed oil (group FXO), or soybean oil (control-group SO) for 30 days. Serum creatinine (sCr), 24-h proteinuria, total cholesterol, triglycerides, and creatinine clearance (CLcr) were measured at day 0 and 30 days after surgery when the rats were euthanized for histological analysis of the remnant kidney. RESULTS: After 30 days, we observed lower levels of sCr in the groups supplemented with PUFA when compared with the control group (FO: 0.92 ± 0.13; FXO: 1.06 ± 0.28; SO: 1.32 ± 0.47 mg/dL) and significantly slower variations of sCr (ΔsCr) in the groups treated with PUFAs (FO = 0.35 ± 0.16; FXO = 0.47 ± 0.31; OS = 0.72 ± 0.43; mg/dL, P = 0.041). Similarly, the CLcr of both of the groups that received PUFAs was significantly slower than the rats in the control group (FO: 0.45 ± 0.15; FXO: 0.60 ± 0.09; SO: 0.28 ± 0.06 mL/min/day; P = 0.01). The rats that received PUFA supplements also presented significantly less histological lesions compared with the control group. CONCLUSIONS: These results suggest a beneficial effect of dietary supplementation with flaxseed or fish oil in rats with CRF.