Energy-restricted diet benefits body composition but degrades bone integrity in middle-aged obese female rats

Nutr Res. 2013 Aug;33(8):668-76. doi: 10.1016/j.nutres.2013.05.008. Epub 2013 Jun 24.


This study investigates the effects of a restricted diet (RD) on body composition and musculoskeletal health along with endocrines and molecular mechanism in established mature obese rats. Twenty female rats were fed with a high-fat diet (HFD) ad libitum for 4 months and then assigned to either HFD or RD group for another 4 months. Another 10 rats were on a low-fat diet for 8 months. Outcome measures included body composition, bone mineral density, microarchitecrure, and strength; serum leptin, adiponectin, insulin-like growth factor I, and liver glutathione peroxidase activity; and protein expression and spleen tumor necrosis factor α messenger RNA expression. We hypothesized that mature obese rats on a 35% energy restriction diet for 4 months would improve body composition but degrade microstructural and mechanical properties of long bones, and such changes in musculoskeletal integrity are related to the modulation of obesity-related endocrines and proinflammation. Relative to HFD, RD benefited body composition (decreased body weight and %fat mass and increased %fat-free mass); decreased insulin-like growth factor I and leptin; elevated adiponectin, glutathione peroxidase activity and protein expression and tumor necrosis factor α messenger RNA expression; and suppressed bone formation and increased bone resorption, resulting in decreased trabecular and cortical bone volume, bone mineral density, and bone strength. Relative to low-fat diet, RD had a similar effect on body composition and serum markers but increased bone turnover rate and decreased bone mineral density and strength. Our data suggest that long-term RD has a negative impact on bone remodeling in obese female rats, probably through modification of endocrines and elevation of proinflammation.

Keywords: ANOVA; BFR/BS; BFR/BV; BIS; BMC; BMD; BS; BV; Body composition; Bone; Ct.Ar; Ct.Th; DXA; ECF; ES; ES/BS; Ec-BFR/BS; Ec-ES/BS; Ec-MS/BS; Energy restriction; FFM; FM; Female rat; GH; GPX; HFD; ICF; IGF-I; LFD; LSD; MAR; MS/BS; Musculoskeletal health; ObS/BS; Obesity; OcS/BS; PCR; Ps-BFR/BS; Ps-MAR; Ps-MS/BS; RD; T.Ar; TBW; TNF-α; TV; Tb.N; Tb.Sp; Tb.Th; analysis of variance; bioimpedance spectroscopy; bone formation rate/bone surface; bone formation rate/bone volume; bone mineral content; bone mineral density; bone surface; bone volume; cDNA; complementary DNA; cortical bone area; cortical thickness; dual-energy x-ray absorptiometry; endocortical bone formation rate; endocortical eroded surface/bone surface; eroded surface; eroded surface/bone surface; extracellular fluid; fat mass; fat-free mass; glutathione peroxidase; growth hormone; high-fat diet; insulin-like growth factor I; intracellular fluid; least significant difference; low-fat diet; mRNA; messenger RNA; mineral apposition rate; mineralizing surface; osteoblast surface per bone surface; osteoclast surface per bone surface; percent endocortical mineralized surface/bone surface; percent periosteal mineralized surface/bone surface; periosteal bone formation rate; periosteal mineral apposition rate; polymerase chain reaction; restricted diet; total body water; total bone area; total volume; trabecular number; trabecular separation; trabecular thickness; tumor necrosis factor α.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adiponectin / blood
  • Animals
  • Biomarkers / blood
  • Body Composition*
  • Bone Density*
  • Bone Resorption / etiology*
  • Bone and Bones* / metabolism
  • Bone and Bones* / physiopathology
  • Caloric Restriction / adverse effects*
  • Diet, Fat-Restricted
  • Diet, High-Fat
  • Female
  • Glutathione Peroxidase / metabolism
  • Insulin-Like Growth Factor I / metabolism
  • Leptin / blood
  • Liver / metabolism
  • Obesity* / complications
  • Obesity* / diet therapy
  • Obesity* / metabolism
  • Osteogenesis / physiology*
  • Proteins / metabolism
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Spleen / metabolism
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / metabolism
  • Weight Loss / physiology


  • Adiponectin
  • Biomarkers
  • Leptin
  • Proteins
  • RNA, Messenger
  • Tumor Necrosis Factor-alpha
  • Insulin-Like Growth Factor I
  • Glutathione Peroxidase