Efeitos de doze semanas de suplementação de whey proteins sobre os biomarcadores de função renal e parâmetros histológicos em ratos wistar sedentários

Abstract

Aim: To verify changes in histological parameters and renal function biomarkers in adult male Wistar rats at the end of 12 weeks of whey proteins supplementation at doses of 2, 4 and 6g/kg/day. Materials and methods: Study performed with 42 rats with an initial age of 60 days and body mass ranging from 250g to 350g randomly distributed in 4 groups, with one control (C) and three intervention groups, identified by the dosage value of the supplement whey proteins (2, 4 and 6g/kg/day –W2, W4 and W6). The protocol lasted 12 weeks with daily supplementation and at the end of the experiment the biomarkers of serum and urinary creatinine, serum and urinary urea, total proteins and proteinuria, as well as the values of creatinine clearance, urine protein/creatinine ratios and serum urea/creatinine values were calculated. Also the right kidney of each rat were weighed and was performed the qualitative histological tubular and quantitative classification of the glomerular radius and the qualitative evaluation of urine by specific reagent strips. Results: The values of urinary creatinine, 24-hour creatinine and creatinine clearance showed significant differences between groups supplemented with group C, in the same way as those of creatinine and serum urea, but within the range of reference values, as well as the total protein biomarker. Glomerular analysis showed mean values within grade I of the scale and without significant differences between groups, while the tubular analysis presented more evident morphological alterations in groups W4 and W6. There were no significant differences in absolute and relative renal mass between groups. Discussion: The results presented by the biomarkers serum and urinary creatinine, 24-hour creatinine, 24-hour relative creatinine, creatinine clearance, relative creatinine clearance, as well as tubular histological analysis evidenced alterations in renal function more evident in groups W4 and W6, but without characterizing impairment of the same. Conclusion: Whey proteins supplementation does not impair renal function