Dietary intervention with vitamin D, calcium, and whey protein reduced fat mass and increased lean mass in rats

• Published in: Nutrition research (New York, N.Y.) Vol. 28; no. 11; pp. 783 - 790
• Main Authors: Siddiqui, Shamim M.K, Chang, Eugene, Li, Jia, Burlage, Catherine, Zou, Mi, Buhman, Kimberly K, Koser, Stephanie, Donkin, Shawn S, Teegarden, Dorothy
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.11.2008; Tarrytown, N.Y.: Elsevier Science Inc; Elsevier
• Subjects: 3-Hydroxybutyric Acid - blood; Adipose Tissue - drug effects; animal models; Animals; Biological and medical sciences; Body composition; Body Composition - drug effects; body fat; Calcium; Calcium, Dietary - administration & dosage; Calcium, Dietary - pharmacology; diet; Dietary Fats - administration & dosage; dietary minerals; dietary supplements; energy metabolism; Fat mass; Fatty Acids, Nonesterified - blood; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; Gastroenterology and Hepatology; Gene Expression; Glucose - metabolism; high fat diet; high sucrose diet; hormone receptors; Insulin; lean body mass; Lean mass; Lipid Peroxidation - drug effects; Liver - drug effects; Liver - enzymology; Male; messenger RNA; Milk Proteins - pharmacology; Muscles - drug effects; Muscles - metabolism; nutritional intervention; Obesity; Overweight - prevention & control; Rats; Rats, Wistar; RNA, Messenger - metabolism; sucrose; Sucrose - administration & dosage; vascular endothelial growth factors; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vitamin D; Vitamin D - pharmacology; Whey; whey protein; Whey Proteins; Lean mass; UCP; Calcium; CPT-1 α; group of animals fed whey protein, high calcium (1.5%), and vitamin D (10 000 IU/kg) diet; phosphoenolpyruvate carboxykinase; Whey; Fat mass; Body composition; uncoupling protein; dual-energy x-ray absorptiometry; Vitamin D; peroxisome proliferative activated receptor γ coactivator-1 α; carnitine palmitoyltransferase-1 α; ACC; Obesity; PEPCK; VEGF; Rats; DXA; Insulin; fatty acid synthase; vascular endothelial growth factor; LD; FAS; acetyl coenzyme A carboxylase; HD; PGC-1 α; group of animals fed diets of suboptimal calcium (0.25%) and vitamin D (400 IU/kg); Pancreatic hormone; Adipose tissue; Rat; Rodentia; Vertebrata; Mammalia; Animal; Morphometry; Whey protein; Nutritional status; Hormonal receptor
• ISSN: 0271-5317; 1879-0739
• DOI: 10.1016/j.nutres.2008.08.004

Abstract The aim of the current study was to determine the effects and the mechanisms of inclusion of dietary whey protein, high calcium, and high vitamin D intake with either a high-sucrose or high-fat base diets on body composition of rodents. Male Wistar rats were assigned to either no whey protein, suboptimal calcium (0.25%), and vitamin D (400 IU/kg) diet (LD), or a diet containing whey protein, high calcium (1.5%), and vitamin D (10 000 IU/kg) diet (HD), and either high-fat (40% of energy) or high-sucrose (60%) base diets for 13 weeks. Liver tissue homogenates were used to determine [14 C]glucose and [14 C]palmitate oxidation. mRNA expression of enzymes related to energy metabolism in liver, adipose, and muscle, as well as regulators of muscle mass and insulin receptor was assessed. The results demonstrated that there was reduced accumulation of body fat mass ( P = .01) and greater lean mass ( P = .03) for the HD- compared to LD-fed group regardless of the background diet. There were no consistent differences between the LD and HD groups across background diets in substrate oxidation and mRNA expression for enzymes measured that regulate energy metabolism, myostatin, or muscle vascular endothelial growth factor. However, there was an increase in insulin receptor mRNA expression in muscle in the HD compared to the LD groups. In conclusion, elevated whey protein, calcium, and vitamin D intake resulted in reduced accumulation of body fat mass and increased lean mass, with a commensurate increase in insulin receptor expression, regardless of the level of calories from fat or sucrose.