title: Birth weight and gender determine expression of adipogenic, lipogenic and adipokine genes in perirenal adipose tissue in the young adult sheep.
abstract: Epidemiological studies have demonstrated that low birth weight is associated with an increased incidence of visceral obesity and metabolic disorders in later life. In the present study, we have determined the impact of birth weight and gender on gene expression in visceral adipose tissue (VAT) in the young adult sheep. Lambs (n=19, birth weight range 2.6-7.55 kg) were born at term and growth monitored for 22.4+/-0.2 weeks, when body composition was determined by Dual X-ray Absorptiometry (DXA) and samples of VAT and subcutaneous (SCAT) adipose tissue collected. Plasma samples were collected at post-mortem for the determination of free fatty acids (FFA), glucose and insulin concentrations. Peroxisome-Proliferator Activated Receptor-gamma (PPARgamma), glycerol-3-phosphate dehydrogenase (G3PDH), lipoprotein lipase (LPL), adiponectin and leptin mRNA expression was determined by qRT-PCR. Fractional growth rate in postnatal weeks 1-3 was inversely related to birth weight in both males and females (R2=0.22, P<0.05, n=19). PPARgamma mRNA expression in VAT, but not SCAT, was inversely related to birth weight (R2=0.60, P<0.01, n=18). In males, but not females, PPARgamma mRNA in VAT was directly related to G3PDH mRNA expression (R2=0.69, P<0.01, n=9). Plasma FFA concentrations were inversely related to birth weight in both males and females (R2=0.22, P<0.05, n=19). These findings demonstrate that low birth weight is associated with an increased expression of a key adipogenic factor in visceral adipose tissue in young adulthood. In males, this is associated with an increased expression of lipogenic genes, and this may contribute to the increased propensity for visceral obesity in low birth weight males compared to females.
authors.affiliation: Early Origins of Adult Health Research Group, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide 5000, Australia. Beverly.Muhlhausler@unisa.edu.au
authors.forename: B S
authors.initials: BS
authors.lastname: Muhlhausler
authors.forename: V
authors.initials: V
authors.lastname: Ritorto
authors.forename: C
authors.initials: C
authors.lastname: Schultz
authors.forename: B E
authors.initials: BE
authors.lastname: Chatterton
authors.forename: J A
authors.initials: JA
authors.lastname: Duffield
authors.forename: I C
authors.initials: IC
authors.lastname: McMillen
mesh_terms: D050156:Adipogenesis / Q000235:genetics*; D054392:Adipokines / Q000235:genetics* / Q000378:metabolism; D052242:Adiponectin / Q000235:genetics / Q000378:metabolism; D000367:Age Factors; D000818:Animals; D001724:Birth Weight / Q000502:physiology*; D001823:Body Composition / Q000235:genetics; D005260:Female; D015870:Gene Expression; D050152:Intra-Abdominal Fat / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism; D050155:Lipogenesis / Q000235:genetics*; D008297:Male; D047495:PPAR gamma / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012727:Sex Characteristics; D012756:Sheep / Q000235:genetics* / Q000254:growth & development; D050151:Subcutaneous Fat / Q000378:metabolism
chemical_list: D054392:Adipokines; D052242:Adiponectin; D047495:PPAR gamma; D012333:RNA, Messenger