title: High-protein diets alters body composition and improves insulin resistance in a rat model of low birth weight.
abstract: OBJECTIVE
  We aimed to investigate the effects of early high-protein supplementation on low birth weight (LBW)-associated adult metabolic disturbances.
  
  
  METHODS
  This study involved 32 LBW rat pups that were fed a normal protein (20% of energy intake) diet or high-protein (30% of energy intake) diet on their first 4 weeks of life. Sixteen rat pups with normal birth weight (NBW) fed the normal-protein diet were included as control. Biochemical measurements were performed at 4 and 12 weeks of age.
  
  
  RESULTS
  Low birth weight offspring showed significantly (P < 0.05) increased fat mass percentage and adipocyte size and decreased lean mass percentage and muscle fiber size relative to NBW offspring. These LBW-related changes in body composition were corrected by high-protein diet intervention. At 12 weeks of age, the fasting insulin level (7.14 ± 0.83 vs 9.27 ± 0.67 mU/L) and homeostasis model of insulin resistance (1.71 ± 0.35 vs 2.30 ± 0.44) were significantly lower in high protein-fed LBW offspring than in normal protein-fed LBW offspring. Low birth weight rat pups showed a significant (P < 0.05) reduction in serum adiponectin concentrations, glucose transporter 4 mRNA abundance, and phosphorylation levels of AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) relative to NBW controls. These LBW-associated alterations in gene expression were reversed by early high-protein treatment.
  
  
  CONCLUSIONS
  Early postnatal high-protein intake alters the body composition and improves insulin resistance in adults with LBW, which is associated with activation of the AMPK and mTOR pathways.
authors.affiliation: Department of Pediatrics, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.
authors.forename: Mu-xue
authors.initials: MX
authors.lastname: Yu
authors.forename: Zhen-yu
authors.initials: ZY
authors.lastname: Shen
authors.forename: Xiao-shan
authors.initials: XS
authors.lastname: Qiu
authors.forename: Qing-ping
authors.initials: QP
authors.lastname: Mo
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001724:Birth Weight / Q000502:physiology*; D001823:Body Composition / Q000502:physiology*; D004044:Dietary Proteins / Q000008:administration & dosage / Q000378:metabolism*; D005260:Female; D007333:Insulin Resistance / Q000502:physiology*; D023421:Models, Animal; D011247:Pregnancy; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013851:Thinness / Q000178:diet therapy / Q000378:metabolism*
chemical_list: D004044:Dietary Proteins