title: Reduced gluteal expression of adipogenic and lipogenic genes in Black South African women is associated with obesity-related insulin resistance.
abstract: BACKGROUND
  Black South African women are less insulin sensitive than their White counterparts, despite less central and greater peripheral fat deposition. We hypothesized that this paradox may be explained, in part, by differences in the adipogenic capacity of sc adipose tissue (SAT).
  
  
  OBJECTIVE
  Our objective was to measure adipogenic and lipogenic gene expression in abdominal and gluteal SAT depots and determine their relationships with insulin sensitivity (S(I)) in South African women.
  
  
  METHODS
  Fourteen normal-weight [body mass index (BMI) <25 kg/m(2)] Black, 13 normal-weight White, 14 obese (BMI >30 kg/m(2)) Black, and 13 obese White premenopausal South African women participated in this cross-sectional study.
  
  
  RESULTS
  S(I) (frequently sampled i.v. glucose tolerance test) in relation to expression of adipogenic and lipogenic genes in abdominal and gluteal SAT depots.
  
  
  RESULTS
  With increasing BMI, Black women had less visceral fat (P = 0.03) and more abdominal (P = 0.017) and gynoid (P = 0.041) SAT but had lower S(I) (P < 0.01) than White women. The expression of adipogenic and lipogenic genes was proportionately lower with obesity in Black but not White women in the gluteal and deep SAT depots (P < 0.05 for ethnicity × BMI effect). In Black women only, the expression of these genes correlated positively with S(I) (all P < 0.05), independently of age and fat mass.
  
  
  CONCLUSIONS
  Obese Black women have reduced SAT expression of adipogenic and lipogenic genes compared with White women, which associates with reduced S(I). These findings suggest that obesity in Black women impairs SAT adipogenesis and storage, potentially leading to insulin resistance and increased risk of type 2 diabetes.
authors.affiliation: University of Cape Town/Medical Research Council Research Unit for Exercise Science and Sports Medicine, University of Cape Town, 3rd Floor Sports Science Institute of South Africa, P.O. Box 115, Newlands 7725, South Africa. julia.goedecke@uct.ac.za
authors.forename: Julia H
authors.initials: JH
authors.lastname: Goedecke
authors.forename: Juliet
authors.initials: J
authors.lastname: Evans
authors.forename: Dheshnie
authors.initials: D
authors.lastname: Keswell
authors.forename: Roland H
authors.initials: RH
authors.lastname: Stimson
authors.forename: Dawn E W
authors.initials: DE
authors.lastname: Livingstone
authors.forename: Philip
authors.initials: P
authors.lastname: Hayes
authors.forename: Kevin
authors.initials: K
authors.lastname: Adams
authors.forename: Joel A
authors.initials: JA
authors.lastname: Dave
authors.forename: Hendriena
authors.initials: H
authors.lastname: Victor
authors.forename: Naomi S
authors.initials: NS
authors.lastname: Levitt
authors.forename: Estelle V
authors.initials: EV
authors.lastname: Lambert
authors.forename: Brian R
authors.initials: BR
authors.lastname: Walker
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Seckl
authors.forename: Tommy
authors.initials: T
authors.lastname: Olsson
authors.forename: Steven E
authors.initials: SE
authors.lastname: Kahn
mesh_terms: D000293:Adolescent; D000328:Adult; D044383:Black People; D001823:Body Composition; D005260:Female; D015870:Gene Expression; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics*; D050152:Intra-Abdominal Fat / Q000378:metabolism; D008875:Middle Aged; D009765:Obesity / Q000208:ethnology / Q000235:genetics* / Q000378:metabolism; D013019:South Africa; D050151:Subcutaneous Fat / Q000378:metabolism*; D044465:White People