Changes in systemic and subcutaneous adipose tissue inflammation and oxidative stress in response to exercise training in obese black African women

Abstract

Key pointsr Inflammation and oxidative stress are interrelated during obesity and contribute to the development of insulin resistance; and exercise training represents a key component in the management of these conditions. r Black African women, despite high gluteal subcutaneous adipose tissue (SAT) and less visceral fat, are less insulin sensitive than their white counterparts.r Exercise training improved systemic oxidative stress in obese black women, which was related to gynoid fat reduction and not insulin sensitivity.r Inflammatory markers changed depot-specifically in response to exercise training, increasing in gluteal SAT without changing in abdominal SAT.r The increase of inflammatory state in gluteal SAT after exercise training is suggested to result from tissue remodelling consecutive to the reduction of gynoid fat but does not contribute to the improvement of whole-body insulin sensitivity in obese black South African women.Abstract Inflammation and oxidative stress are interrelated during obesity and contribute to the development of insulin resistance. Exercise training represents a key component in the management of obesity. We evaluated the effects of 12 weeks' combined resistance and aerobic exercise training on systemic and abdominal vs. gluteal subcutaneous adipose tissue (SAT) inflammatory and oxidative status in obese black South African women. Before and after the intervention, body composition (dual energy X-ray absorptiometry), cardio-respiratory fitness (VO 2peak ), serum and SAT inflammatory and oxidative stress markers were measured from 15 (control group) and 20 (exercise group) women and insulin sensitivity (S I ; frequently sampled Pamela A. Nono Nankam is a third year PhD candidate at the department of Human Biology, Faculty of Health Science at the University of Cape Town and assistant researcher at the department of Endocrinology, Medical Faculty of the University of Leipzig. Her main research range includes obesity mechanisms, adipose tissue dysfunction and insulin resistance. Her principal focus is on human studies, with the aim of using lifestyle interventions such as exercise training to understand the mechanisms underlying the alteration of adipose tissue function and body fat distribution during obesity and the relationship with insulin resistance and metabolic syndrome, particularly in African populations. P. A. Nono Nankam and othersJ Physiol 598.3intravenous glucose tolerance test) was estimated. Following the intervention, VO 2peak (9.8%), body fat composition (1-3%) and S I (9%) improved, serum thiobarbituric acid reactive substances (TBARS) decreased (6.5%), and catalase activity increased (23%) in the exercise compared to the control group (P < 0.05), without changes in circulating inflammatory markers. The mRNA content of interleukin-10, tumour necrosis factor α, nuclear factor κB and macrophage migration inhibitory factor increased in the gluteal SAT exercise compared to the control group P < 0.05), with no changes in abdominal SAT. These changes of inflammatory prof...

Exercise Training Alters Red Blood Cell Fatty Acid Desaturase Indices and Adipose Tissue Fatty Acid Profile in African Women with Obesity

“…However, further investigation is needed to validate this hypothesis, as systemic inflammation did not decrease in response to this exercise training intervention. Rather, inflammatory gene expression, mainly in gSAT, was upregulated, reflecting tissue remodeling as previously reported (35). Noteworthy, the lack of association between the changes in RBC‐TPL desaturases and DGLA content and changes in insulin sensitivity following this exercise training intervention suggests that the improvement of whole‐body insulin sensitivity after exercise training is not directly mediated by the changes in circulating FA metabolism.…”

“…The participants' characteristics are presented in Supporting Information Table S2 and they have been partly published in (28,35). In brief, cardiorespiratory fitness and body composition were not different between the groups at baseline.…”

Contribution of Adipose Tissue Oxidative Stress to Obesity-Associated Diabetes Risk and Ethnic Differences: Focus on Women of African Ancestry

“…Further, higher catalase activity in VAT was an independent determinant of IR in this study [76]. Notably, we recently showed an improvement of systemic oxidative stress in response to exercise training in black African women with obesity, but this was not correlated with the reported improvement in insulin sensitivity [143]. Interestingly, we did not find significant associations between SAT oxidative stress markers (eNOS, SOD and catalase genes) and whole-body insulin sensitivity.…”

“…Interestingly, we did not find significant associations between SAT oxidative stress markers (eNOS, SOD and catalase genes) and whole-body insulin sensitivity. We rather showed positive correlations between increased inflammatory markers and increased SOD and catalase expression in gluteal SAT [143]. These data suggest that associations between SAT oxidative stress and IR in black African women might be mediated via the complex interrelation with inflammation, mitochondrial dysfunction or hypoxia, which were not directly assessed in our study [143].…”

“…We rather showed positive correlations between increased inflammatory markers and increased SOD and catalase expression in gluteal SAT [143]. These data suggest that associations between SAT oxidative stress and IR in black African women might be mediated via the complex interrelation with inflammation, mitochondrial dysfunction or hypoxia, which were not directly assessed in our study [143]. Taken together, more studies on AT-related disease mechanisms in individuals of African ancestry and involving larger sample sizes are needed.…”