View source for DeLany 2013 TOS

{{Abstract
|title=Skeletal muscle mitochondrial respiration is lower in African American compared to Caucasian women and is associated with resting metabolic rate and cardiorespiratory fitness.
|info=[http://docplayer.net/12499193-Obesity-2013-abstract-book.html Open Access]
|authors=DeLany JP, Distefano G, Coen PM, Toledo FGS, Dube JJ, Stefanovic-Racic M, Goodpaster BH
|year=2013
|event=The Obesity Society
|abstract=The prevalence of obesity is greater in African American women (AAW) compared to Caucasian women (CW). Lower energy expenditure, particularly lower resting metabolic rate (RMR) is observed in AAW. This low RMR may play a role in the greater obesity in AAW, but reasons for this difference are not known.

We examined skeletal muscle mitochondrial respiration, cardiorespiratory fitness (VO<sub>2</sub> peak), and RMR in young (23.8±4.8 y) healthy women. We present data from 20 AAW (22.7±4.0 kg/m<sub>2</sub>, 62±9 kg) and 22 CW (22.7±3.1 kg/m<sub>2</sub>; 63±9 kg) matched for BMI and weight. Percutaneous biopsies of the vastus lateralis were obtained following an overnight fast. Mitochondrial respiratory properties were determined in permeabilized muscle fiber bundles by high-resolution respirometry. RMR was measured by indirect calorimetry, and VO<sub>2</sub> peak was determined during a graded exercise test. 

Basal (State 4; 67±16 vs. 82±18 pmol O<sub>2</sub>/sec/mg; p<0.015), maximal coupled (State 3; 320±68 vs. 422±65 pmol O<sub>2</sub>/sec/mg; p<0.001) and uncoupled (State U; 354±76 vs. 483±69 pmol O<sub>2</sub>/sec/mg; p<0.001) respiration were lower in AAW compared to CW. This corresponded with lower RMR (1259±185 vs 1383±178 kcal/day; p<0.01) and VO<sub>2</sub> peak (2007±428 vs 2320±491 ml/min; p< 0.03) in AAW. When combining groups, State 4, State 3 and State U respiration correlated positively with RMR (r=0.44, p<0.01; r=0.39, p<0.03; r=0.40, p<0.02) and VO<sub>2</sub> peak (r=0.54, p<0.001; r=0.48, p<0.002; r=0.48, p<0.003).

In summary, RMR and VO<sub>2</sub> peak were lower in these young, lean AWW compared with matched CW. Skeletal muscle mitochondrial respiration was also lower in AWW and was associated with RMR and VO<sub>2</sub> peak. These data suggest that differences in skeletal muscle mitochondrial respiration are related to the lower metabolic rate in AAW and may be related to the increased risk of weight gain in AA women.
|editor=[[Kandolf G]],
|mipnetlab=US PA Pittsburgh DeLany JP, US FL Orlando Goodpaster BH
}}
{{Labeling
|area=Respiration
|diseases=Obesity
|organism=Human
|tissues=Skeletal muscle
|preparations=Permeabilized tissue
|couplingstates=LEAK, OXPHOS
|instruments=Oxygraph-2k
}}