The protective effect of flaxseed oil on lead acetate-induced renal toxicity in rats

Lead is a toxic metal inducing many destructive effects leading to a broad range of physiological, biochemical, and neurological dysfunctions in humans. Here, we investigated the effects of flaxseed oil (1000 mg/kg) on the outcome of renal cytotoxicity induced by lead acetate (20 mg/kg) in male rats. Lead induced injury of the renal tissue. This was evidenced (i) as increases in lead concentration in the kidney, (ii) as increases in the histopathological damage of the renal tissue, (iii) as increases in uric acid, urea and creatinine, (iv) as increases in lipid peroxidation, nitric oxide and reactive oxygen species, and (v) as lowered glutathione levels and decreased activities of catalase and superoxide dismutase, glutathione reductase, glutathione S transferase, and glutathione peroxidase, respectively. All these lead induced parameters were significantly altered during flaxseed oil treatment. Therefore, our study suggests the role of flaxseed oil in limiting renal cytotoxicity induced by lead acetate as a model for lead toxicity. (Auhtors abstract)

Lead (Pb), is a common environmental toxin that is capable of causing numerous acute and chronic illnesses. The kidney is the critical organ after long-term occupational or environmental exposure to Pb. Excessive exposure to lead may cause acute or chronic nephrotoxic effects. Acute Pb nephropathy is characterized functionally by a generalized deficit of tubular transport mechanisms and morphologically by the appearance of degenerative changes in the tubular epithelium and the nuclear inclusion bodies containing Pb protein complexes. The objective of the present study was to evaluate the antioxidant efficacy of the flaxseed oil against lead acetate-induced renal cytotoxicity in adult male albino rats. The results indicated that treatment with flaxseed oil did not induce harmful effects on the animals. Flaxseed oil was found to reduce the accumulation of PbAc in kidney. The authors speculated that theses effects could be due to alpha linolenic acid (ALA). They also indicated that fibers and lignans may play a role. However, this is an erroneous statement as flax oil does not contain fibre or lignans. Histological investigations revealed that PbAc exposure caused progressive glomerular and tubular alterations which were improved with feeding flaxseed oil. Induced elevation of the uric acid, urea and creatinine due to PbAc administration indicated that the kidney function was affected. Treatment with flaxseed oil significantly
improved the kidney function.  In the current study, co-treatment of PbAc and flaxseed oil caused a significant improvement in histopathological picture of the kidney as well as the kidney function and antioxidant status. This results of the study are compromised by the inaccurate characterizations made by the authors throughout the paper regarding flax oil. Specifically the authors attribute many of their findings to fibre and lignans that are found in flaxseed not in flax oil. (Editors comments)