Functional and Morphostructural Evaluation of the Kidneys of Wistar Rats after the Use of a Protein-Based Food Supplement

Abstract

Introduction: Athletes are increasingly using whey protein–based dietary supplements that, used improperly, may create health risks. Objective: To evaluate changes in glomerular filtration, renal tubular function, and histopathological alterations associated with the use of protein-rich food supplements on the kidneys of Wistar rats. Method: Twelve Wistar rats were divided into control (Group I) and intervention (Group II) groups. Group II received the supplement for 14 fourteen days. Urine samples were collected from the animals for urinalysis and blood samples were collected for the determination of urea, creatinine, sodium, potassium, and chloride levels. At the end of the experiment, the animals were euthanized and the kidneys were collected for a histopathological study. Results: After the supplementation, reduced urea levels (p=0.00930) and increased urinary density (p=0.4645) were observed in Group II. The vast majority of Group II animals (67%) had significant proteinuria (p=0.040), and epithelial cells and waxy casts occurred in 50% and 67%, respectively. Histological analysis of the kidneys showed the presence of areas of peritubular blood vessel dilation and congested glomeruli. Conclusion: Use of the protein supplement changed glomerular filtration and tubular function as evidenced by significantly increased proteinuria as well as peritubular, glomerular, and vascular congestion on histopathological analysis.