title: Three weeks of early-onset exercise prolongs obesity resistance in DIO rats after exercise cessation.
abstract: We assessed the effect of early-onset exercise as a means of preventing childhood obesity using juvenile male rats selectively bred to develop diet-induced obesity (DIO) or to be diet resistant (DR) when fed a 31% fat high-energy diet. Voluntary wheel running begun at 36 days of age selectively reduced adiposity in DIO vs. DR rats. Other 4-wk-old DIO rats fed a high-energy diet and exercised (Ex) for 13 wk increased their core temperature, gained 22% less body weight, and had 39% lighter fat pads compared with sedentary (Sed) rats. When wheels were removed after 6 wk (6 wk Ex/7 wk Sed), rats gained less body weight over the next 7 wk than Sed rats and still had comparable adipose pad weights to 13-wk-exercised rats. In fact, only 3 wk of exercise sufficed to prevent obesity for 10 wk after wheel removal. Terminally, the 6-wk-Ex/7-wk-Sed rats had a 55% increase in arcuate nucleus proopiomelanocortin mRNA expression vs. Sed rats, suggesting that this contributed to their sustained obesity resistance. Finally, when Sed rats were calorically restricted for 6 wk to weight match them to Ex rats (6 wk Rstr/7 wk Al), they increased their intake and body weight when fed ad libitum and, after 7 wk more, had higher leptin levels and adiposity than Sed rats. Thus, early-onset exercise may favorably alter, while early caloric restriction may unfavorably influence, the development of the hypothalamic pathways controlling energy homeostasis during brain development.
authors.affiliation: Department of Neurosciences, New Jersey Medical School, Newark, NJ, USA.
authors.forename: Christa M
authors.initials: CM
authors.lastname: Patterson
authors.forename: Ambrose A
authors.initials: AA
authors.lastname: Dunn-Meynell
authors.forename: Barry E
authors.initials: BE
authors.lastname: Levin
mesh_terms: D000273:Adipose Tissue / Q000502:physiology; D000821:Animal Feed; D000818:Animals; D001835:Body Weight / Q000502:physiology*; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics; D031204:Caloric Restriction; D004435:Eating / Q000502:physiology; D007031:Hypothalamus / Q000502:physiology*; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000097:blood; D008297:Male; D009478:Neuropeptide Y / Q000235:genetics; D009765:Obesity / Q000503:physiopathology* / Q000517:prevention & control*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D011333:Pro-Opiomelanocortin / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D054411:Receptors, Leptin / Q000235:genetics; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins / Q000235:genetics
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D007328:Insulin; D020738:Leptin; D009478:Neuropeptide Y; D012333:RNA, Messenger; D054411:Receptors, Leptin; C491410:Socs3 protein, rat; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins; D011333:Pro-Opiomelanocortin