OBJECTIVE: The aim of this study was to assess the effect of whey protein consumption on the lipid, hepatic and renal metabolism, bone formation and antioxidant defense system of rats given a hypercholesterolemic diet. METHODS: A total of 32 adult Fisher rats were divided into 4 groups: C group, standard diet; H group, hypercholesterolemic diet; WP group, standard diet with whey protein; WPH group, hypercholesterolemic diet with whey protein. Food ingestion and weight gain were monitored weekly. After 8 weeks, blood was collected for biochemical analysis and the rats were killed. The statistical tests analysis of variance and Tukey's test were performed. RESULTS: Whey protein did not lower serum cholesterol significantly and increased serum triglycerides in hypercholesterolemic rats. However, whey protein decreased the activity of aspartate aminotransferase and alkaline phosphatase, as well as serum creatinine. The assessed antioxidant defenses were not affected. Diets containing whey protein generated heavier, thicker and longer bones than casein diets. CONCLUSION: Whey proteins did not have a significant hypocholesterolemic effect in rats. On the other hand, they significantly prevented changes in liver and kidney functions brought about by hypercholesterolemic diets. Data also suggest that whey proteins benefit bone formation when compared with casein diets.
Amino Acids; Aspartate aminotransferases; Alkaline phosphatase; Cholesterol; Hypercholesterolemia; Peptides and proteins
