Toward an animal model of childhood-onset obesity: follow-up of OLETF rats during pregnancy and lactation.
The Otsuka Long-Evans Tokushima Fatty (OLETF) rat model of obesity (a spontaneous CCK1 receptor knockout) has been extensively studied as model of hyperphagia-induced obesity. In previous studies, young OLETF rats presented abnormal eating patterns [compared with Long-Evans Tokushima Otsuka (LETO) controls] in a variety of independent ingestion and nursing tests during the suckling period. The aim of the present study was to characterize the early emergence of abnormal adiposity in the pups. Moreover, because both the dams and the pups present the genetic mutation, a close follow-up of the dams' body weight and intake during pregnancy and lactation was performed to examine the circumstances that contribute to build up the pups' early adiposity. Compared with controls, OLETF pups presented higher fat levels, larger adipocytes, and increased waist circumference as early as postnatal day 7 and this profile persisted to the age of weaning. While LETO dams gained weight throughout pregnancy and lactation, OLETF dams were obese and hyperphagic during pregnancy but lost weight during lactation, probably as a result of rearing hyperphagic pups. Current and previous results suggest a possible influence of the dams' obesity during gestation and a high investment in nursing time during lactation on the pups' obesity levels during childhood. This, combined with the innate hyperphagia repeatedly observed in the pups at these early ages, makes the OLETF strain a useful tool in the research of childhood-onset obesity.
Schroeder
Mariana
M
Life Sciences Faculty, Bar Ilan University, Ramat Gan 52900, Israel.
Shbiro
Liat
L
Zagoory-Sharon
Orna
O
Moran
Timothy H
TH
Weller
Aron
A
D017667:Adipocytes / Q000473:pathology; D002001:Adipose Tissue, Brown / Q000473:pathology; D050154:Adiposity / Q000235:genetics; D000367:Age Factors; D017668:Age of Onset; D000375:Aging; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D000831:Animals, Newborn; D000833:Animals, Suckling; D015992:Body Mass Index; D001835:Body Weight; D004195:Disease Models, Animal; D002149:Energy Intake; D005247:Feeding Behavior; D005260:Female; D006963:Hyperphagia / Q000503:physiopathology; D007774:Lactation; D020738:Leptin / Q000097:blood; D008297:Male; D039382:Maternal Nutritional Physiological Phenomena; D009765:Obesity / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D011247:Pregnancy; D011270:Pregnancy, Animal; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D020334:Rats, Inbred OLETF; D043886:Receptor, Cholecystokinin A / Q000235:genetics; D014886:Weaning
D020738:Leptin; D043886:Receptor, Cholecystokinin A