Chávez-Guevara Isaac A, Amaro-Gahete Francisco J, Osuna-Prieto Francisco J, Labayen Idoia, Aguilera Concepcion M, Ruiz Jonatan R
Department of Chemical Sciences, Biomedical Sciences Institute, Autonomous University of Ciudad Juarez, Chihuahua, Mexico.
Department of Physical Education and Sports, Faculty of Sports Science, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain; CIBER de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Granada, Spain; Instituto de Investigación Biosanitaria, ibs. Granada, Granada, Spain.
Biochem Pharmacol. 2023 Oct;216:115757. doi: 10.1016/j.bcp.2023.115757. Epub 2023 Aug 19.
Previous evidence suggest that a sexual dimorphism in exercise fat oxidation and adipokines levels may explain a lower risk of cardio-metabolic disorders in women. Therefore, we investigated the role of sex in the relationship between adipokines levels, maximal fat oxidation (MFO) during exercise and insulin resistance.
Fifty young adults with excess adiposity (31 women; body fat: 38.7 ± 5.3%) were included in this study. The fasting levels of leptin, adiponectin, glucose and insulin were determined from blood samples and the homeostatic model assessment of insulin resistance index (HOMA-IR) subsequently calculated. Body fat percentage and visceral adipose tissue (VAT) were assessed through dual-energy X-ray absorptiometry whereas MFO was estimated during an incremental-load exercise test after an overnight fasting through indirect calorimetry.
Men had lower levels of body fat (d = 1.80), adiponectin (d = 1.35), leptin (d = 0.43) and MFO (d = 1.25) than women. Conversely, men showed higher VAT (d = 0.85) and fasting glucose levels (d = 0.89). No sex differences were observed in HOMA-IR (d = 0.34). Adipokines levels were not associated with MFO in both sexes (r < 0.30), whereas adiponectin levels were inversely related with HOMA-IR in both men (r = -0.58) and women (r = -0.50). Leptin concentration was associated to HOMA-IR only in men (r = 0.41), while no statistically significant relationships were observed between MFO and HOMA-IR in both sexes (r < 0.44).
Insulin resistance was similar between sexes regardless of superior levels of adipokines and MFO during exercise in women. Therefore, adiponectin and leptin may regulate glucose homeostasis without altering whole body fat oxidation rate during exercise.
先前的证据表明，运动脂肪氧化和脂肪因子水平的性别差异可能解释了女性心血管代谢紊乱风险较低的原因。因此，我们研究了性别在脂肪因子水平、运动期间最大脂肪氧化（MFO）与胰岛素抵抗之间关系中的作用。
本研究纳入了50名肥胖的年轻人（31名女性；体脂：38.7±5.3%）。通过血液样本测定瘦素、脂联素、葡萄糖和胰岛素的空腹水平，并随后计算胰岛素抵抗指数（HOMA-IR）的稳态模型评估值。通过双能X线吸收法评估体脂百分比和内脏脂肪组织（VAT），而在过夜禁食后的递增负荷运动试验期间，通过间接量热法估计MFO。
男性的体脂（d = 1.80）、脂联素（d = 1.35）、瘦素（d = 0.43）和MFO（d = 1.25）水平低于女性。相反，男性的VAT（d = 0.85）和空腹血糖水平（d = 0.89）较高。在HOMA-IR方面未观察到性别差异（d = 0.34）。脂肪因子水平在两性中均与MFO无关（r < 0.30），而脂联素水平在男性（r = -0.58）和女性（r = -0.50）中均与HOMA-IR呈负相关。瘦素浓度仅在男性中与HOMA-IR相关（r = 0.41），而在两性中MFO与HOMA-IR之间均未观察到统计学上的显著关系（r < 0.44）。
无论女性运动期间脂肪因子和MFO水平较高，两性之间的胰岛素抵抗相似。因此，脂联素和瘦素可能在不改变运动期间全身脂肪氧化率的情况下调节葡萄糖稳态。
