Dietary constituents, such as sucrose, may influence renal integrity during aging. Diets with high sucrose content cause extensive basement membrane damage in retinal vessels of WKY rats (J Clin Lab Sci 16: 419, 1986), which have been likened to the changes in diabetes mellitus and aging. Nevertheless, it is unknown whether similar lesions also occur in renal glomeruli and play a role in the progressive decline of renal function during aging. Knowledge of the latter possibility is important, because eye and renal vascular pathology often correlate, and earlier publications indicated that renal perturbations result from high sugar intake.
In sharp contrast to work reported by others, our initial studies using Wistar rats showed no evidence of renal perturbations during months of high sucrose intake. We used diets formulated to be virtually the same in electrolyte and vitamin content, with the only differences being in the proportion of macronutrients — CHO (sucrose), fats and protein. To corroborate the initial studies, we expanded the studies using 40 unilaterally nephrectomized WKY rats. Despite marked differences in the consumption of macronutrients over a 6–7 month period, differences in kidney function and morphology were not seen among any of the 4 dietary groups. Although protein excretion was significantly higher in WKY rats consuming a low sucrose-high fat diet and BP was significantly higher in the rats consuming diets high in sucrose content, serum urea nitrogen and creatinine and urinary findings did not suggest renal damage secondary to high sucrose consumption. Light and electron microscopy failed to show renal morphological differences among the groups, similar to those reported in the vasculature of the eye. Based upon the ability of kidney slices to transport organic ions and consume OZ , renal tubular function also was not affected by different diets. We conclude that excess ingestion of sucrose over months causes no obvious renal perturbations in WKY rats, even though it elevates BP and causes eye lesions.
sugareffect on renal function and morphologysugareffect on blood pressurerenal function during agingsucrose