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- Goedecke, Julia H, et al.
(författare)
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Reduced gluteal expression of adipogenic and lipogenic genes in black south african women is associated with obesity-related insulin resistance
- 2011
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - Philadelphia : Lippincott Williams & Wilkins. - 0021-972X .- 1945-7197. ; 96:12, s. E2029-E2033
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Tidskriftsartikel (refereegranskat)abstract
- Context: 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. Participants and Design: 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.Main outcomes:S(I) (frequently sampled iv 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.
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| 2. |
- McInnes, Kerry J., et al.
(författare)
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Association of 11 beta-hydroxysteroid dehydrogenase type I expression and activity with estrogen receptor beta in adipose tissue from postmenopausal women
- 2012
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Ingår i: Menopause. - : Ovid Technologies (Wolters Kluwer Health). - 1072-3714 .- 1530-0374. ; 19:12, s. 1347-1352
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Tidskriftsartikel (refereegranskat)abstract
- Objective: 11 beta-Hydroxysteroid dehydrogenase type I (11 beta HSD1) regenerates active cortisol from inert cortisone in adipose tissue. Elevated adipose tissue 11 beta HSD1 activity is observed in obese humans and rodents, where it is linked to obesity and its metabolic consequences. Menopause is also associated with increased abdominal fat accumulation, suggesting that estrogen is also important in adipose tissue metabolism. The purpose of this current study was to establish whether estrogen signaling through estrogen receptor alpha (ER-alpha) and estrogen receptor beta (ER-beta) could influence 11 beta HSD1 in premenopausal and postmenopausal adipose tissues. Methods: Nineteen premenopausal (aged 26 +/- 5 y; body mass index, 23.6 +/- 1.6 kg/m(2)) and 23 postmenopausal (aged 63 +/- 4 y; body mass index, 23.4 +/- 1.9 kg/m(2)) healthy women were studied. Subcutaneous adipose tissue biopsies and fasting venous blood samples were taken. Body composition was measured by bioelectrical impedance analysis. Human Simpson-Golabi-Behmel syndrome adipocyte cells were treated with ER-alpha- and ER-beta-specific agonists for 24 hours. Basic anthropometric data, serum 17 beta-estradiol and progesterone concentrations, ER-alpha and ER-beta messenger RNA (mRNA) levels, and 11 beta HSD1 mRNA, protein, and activity levels were assessed. Results: ER-beta and 11 beta HSD1, but not ER-alpha, mRNAs were significantly increased in adipose tissue from postmenopausal women compared with premenopausal women. ER-beta had a significant positive correlation with the mRNA level of 11 beta HSD1 in adipose tissue from premenopausal and postmenopausal women. This association between ER-beta and 11 beta HSD1 was greatest in adipose tissue from postmenopausal women. In human Simpson-Golabi-Behmel syndrome adipocytes, diarylpropiolnitrile, a selective ER-beta agonist, increased 11 beta HSD1 mRNA, protein, and activity levels. Conclusions: We conclude that, in adipose tissue, ER-beta-mediated estrogen signaling can up-regulate 11 beta HSD1 and that this may be of particular importance in postmenopausal women.
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