The impact of long-term consumption of diets enriched with olive, cottonseed or sesame oils on kidney morphology: A stereological study.

To date, most of studies have only focused on metabolic effects of dietary oils while recent evidence proposes that they can influence kidneys structure. Therefore, the aim of this study was to evaluate the impact of long-term consumption of olive, cottonseed and sesame oils on renal morphology in rats. 70 male Wistar rats randomly assigned into seven equal groups and treated with standard diet (control), the standard diet enriched with 10% or 20% (W/W) of either olive oil (OLI10%, OLI20%), cottonseed oil (COT10%, COT20%) or sesame oil (SES10%, SES20%) for 5 months. Quantitative features of the kidney including kidney and cortex volumes and the number of glomeruli were analyzed stereologically. Moreover, kidney sections histologically were evaluated. All of the studied oils in low concentration had no devastating effects on renal morphology and also its pathological features. However, only in SES20% group, kidney volume as well as, cortical volume was higher than the control group. Besides, accumulation of carbohydrate macromolecules and renal fibrosis were markedly increased in SES20% group compared to the control. The results suggest that sesame oil, especially at high concentration, may lead to renal deformities as a result of histopathological changes such as dilatation, fibrosis, and tubular defects.