| Autor: |
Mendham AE; Non-communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa. amy.mendham@uct.ac.za.; Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa. amy.mendham@uct.ac.za., Larsen S; Center for Healthy Aging, Department of Biomedical Sciences, Copenhagen University, Copenhagen, Denmark.; Clinical Research Centre, Medical University of Bialystok, Bialystok, Poland., George C; Non-communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa., Adams K; Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa., Hauksson J; Department of Radiation Sciences, Radiation Physics and Biomedical Engineering, Umeå University, Umeå, Sweden., Olsson T; Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden., Fortuin-de Smidt MC; Non-communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa.; Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa., Nono Nankam PA; Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa., Hakim O; Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK., Goff LM; Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK., Pheiffer C; Biomedical Research and Innovation Platform, South African Medical Research Council, Cape Town, South Africa., Goedecke JH; Non-communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa.; Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa. |
| Abstrakt: |
We assessed differences in mitochondrial function in gluteal (gSAT) and abdominal subcutaneous adipose tissue (aSAT) at baseline and in response to 12-weeks of exercise training; and examined depot-specific associations with body fat distribution and insulin sensitivity (S I ). Obese, black South African women (n = 45) were randomized into exercise (n = 23) or control (n = 22) groups. Exercise group completed 12-weeks of aerobic and resistance training (n = 20), while the control group (n = 15) continued usual behaviours. Mitochondrial function (high-resolution respirometry and fluorometry) in gSAT and aSAT, S I (frequently sampled intravenous glucose tolerance test), body composition (dual-energy X-ray absorptiometry), and ectopic fat (MRI) were assessed pre- and post-intervention. At baseline, gSAT had higher mitochondrial respiratory capacity and hydrogen peroxide (H 2 O 2 ) production than aSAT (p < 0.05). Higher gSAT respiration was associated with higher gynoid fat (p < 0.05). Higher gSAT H 2 O 2 production and lower aSAT mitochondrial respiration were independently associated with lower S I (p < 0.05). In response to training, S I improved and gynoid fat decreased (p < 0.05), while H 2 O 2 production reduced in both depots, and mtDNA decreased in gSAT (p < 0.05). Mitochondrial respiration increased in aSAT and correlated with a decrease in body fat and an increase in soleus and hepatic fat content (p < 0.05). This study highlights the importance of understanding the differences in mitochondrial function in multiple SAT depots when investigating the pathophysiology of insulin resistance and associated risk factors such as body fat distribution and ectopic lipid deposition. Furthermore, we highlight the benefits of exercise training in stimulating positive adaptations in mitochondrial function in gluteal and abdominal SAT depots. |
