TY - JOUR
T1 - Effect of adipose tissue on the sexual dimorphism in metabolic flexibility
AU - Sparks, Lauren M.
AU - Pasarica, Magdalena
AU - Sereda, Olga
AU - deJonge, Lilian
AU - Thomas, Shantele
AU - Loggins, Heather
AU - Xie, Hui
AU - Miles, John M.
AU - Smith, Steven R.
N1 - Funding Information:
This work was supported by United States Department of Agriculture grant 2003-34323-14010 and United States Public Health Service grant HL67933. We thank the study participants. All primer/probe sets were manufactured by Biosearch Technologies (Hercules, CA).
PY - 2009/11
Y1 - 2009/11
N2 - Metabolic flexibility is the ability to transition between fat oxidation (fasting state) and glucose oxidation (fed state). We hypothesized that adipose tissue inflammation and lipid metabolism contribute to sexual dimorphism in metabolic flexibility. Respiratory quotient (ΔRQ, metabolic flexibility) and nonesterified fatty acids (NEFAs) before and during euglycemic-hyperinsulinemic clamp were measured in healthy young women (n = 22) and men (n = 56). Adiponectin levels were measured in plasma. Abdominal subcutaneous adipose tissue gene expression was measured by quantitative reverse transcriptase polymerase chain reaction. As compared with men, women had higher ΔRQ (0.14 ± 0.04 vs 0.09 ± 0.04, P < .01). Fasting RQ and fat cell size were not different between sexes. As compared with men, women had lower insulin-suppressed NEFAs (P < .05); greater adiponectin levels; and higher expression of adipogenesis, fatty acid storage, and oxidation genes (PPARγ2, PCK1, SCD1, and PPARα; P < .05). There were no sex differences in messenger RNA of macrophage markers or chemokines. Stepwise regression analysis revealed that the only adipose tissue characteristics that influenced metabolic flexibility in women were SCD1 and PCK1 messenger RNA (model R2 = 0.49, P < .05); in men, these were serum adiponectin and insulin-suppressed NEFAs (model R2 = 0.34, P < .05). Healthy young women are more metabolically flexible than men, driven by an increase in insulin-stimulated glucose oxidation rather than differences in fasting fat oxidation. Women have greater capacity for insulin suppression of NEFAs despite similar chemokine and macrophage content in adipose tissue. Combined, these results provide evidence for a role of adipose tissue characteristics in the sexual dimorphism of metabolic flexibility.
AB - Metabolic flexibility is the ability to transition between fat oxidation (fasting state) and glucose oxidation (fed state). We hypothesized that adipose tissue inflammation and lipid metabolism contribute to sexual dimorphism in metabolic flexibility. Respiratory quotient (ΔRQ, metabolic flexibility) and nonesterified fatty acids (NEFAs) before and during euglycemic-hyperinsulinemic clamp were measured in healthy young women (n = 22) and men (n = 56). Adiponectin levels were measured in plasma. Abdominal subcutaneous adipose tissue gene expression was measured by quantitative reverse transcriptase polymerase chain reaction. As compared with men, women had higher ΔRQ (0.14 ± 0.04 vs 0.09 ± 0.04, P < .01). Fasting RQ and fat cell size were not different between sexes. As compared with men, women had lower insulin-suppressed NEFAs (P < .05); greater adiponectin levels; and higher expression of adipogenesis, fatty acid storage, and oxidation genes (PPARγ2, PCK1, SCD1, and PPARα; P < .05). There were no sex differences in messenger RNA of macrophage markers or chemokines. Stepwise regression analysis revealed that the only adipose tissue characteristics that influenced metabolic flexibility in women were SCD1 and PCK1 messenger RNA (model R2 = 0.49, P < .05); in men, these were serum adiponectin and insulin-suppressed NEFAs (model R2 = 0.34, P < .05). Healthy young women are more metabolically flexible than men, driven by an increase in insulin-stimulated glucose oxidation rather than differences in fasting fat oxidation. Women have greater capacity for insulin suppression of NEFAs despite similar chemokine and macrophage content in adipose tissue. Combined, these results provide evidence for a role of adipose tissue characteristics in the sexual dimorphism of metabolic flexibility.
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U2 - 10.1016/j.metabol.2009.05.008
DO - 10.1016/j.metabol.2009.05.008
M3 - Article
C2 - 19595383
AN - SCOPUS:70449723308
SN - 0026-0495
VL - 58
SP - 1564
EP - 1571
JO - Metabolism: Clinical and Experimental
JF - Metabolism: Clinical and Experimental
IS - 11
ER -