The Percentage Of Non-classical Monocytes In Obese Individuals Is Reduced By High-intensity Interval Training

Abstract

Obesity is associated with both metabolic and inflammatory disturbances. Exercise training represents an efficacious strategy to modulate these deleterious aspects of obesity. PURPOSE: To evaluate the effects of high-intensity interval training (HIIT) in monocyte subtypes distribution patterns of obese individuals. METHODS: Nine lean control (CON, BMI = 20.8 ± 1.7 kg•m-2), nine obese insulin sensitive (OBS, BMI = 35.1 ± 3.8 kg•m-2) and nine obese insulin resistant (OBR, BMI = 37.8 ± 4.6 kg•m-2) subjects were used in this study. The OBS and OBR underwent 8 weeks of HIIT, 3 x/week, using a cycle ergometer, with progressive increases in intensity and volume (8 to 12 bouts of 1 min at 80 to 110% of the maximum power output separated by 1 min active recovery at 30 W). Insulin resistance was defined as homeostasis model assessment index (HOMA- IR) ≥ 2.71. Venous blood was collected after 12 hours fasting, before and after HIIT for the quantification of monocyte subtypes (classics, intermediaries and non-classics) and metabolic parameters (insulin, glucose, triglycerides and cholesterol fractions). β-pancreatic cell function (HOMA-β) were also calculated. Volunteers also underwent an oral glucose tolerance test (OGTT). Body composition was evaluated using dual-energy X-ray absorptiometry (DXA). RESULTS: Pre-training blood triglycerides, VLDL- cholesterol, HOMA- β and insulin concentration were higher (p<0.05) in OBR compared to OBS and CON. OBR also had higher mass of visceral adipose tissue compared to OBS and CON (1,785 ± 754, 1,153 ± 431 and 149 ± 80 g, respectively). Both OBS and OBR individuals had increased (p<0.05) percentage of non-classical monocytes (11.0 ±5.5 and 12.2 ± 5.9%, respectively), compared to CON (4.8 ± 2.2%). The percentage of non-classical monocytes was positively correlated to BMI, fat percentage, HOMA-β and OGTT. After 8 weeks of HIIT, the frequency of non-classical monocytes was reduced (p<0.05) by almost 40% in OBS and OBR (12.1 ± 5.6 and 8.7 ± 3.2%, pre- and post-HIIT, respectively). Although training had no effect on BMI and body fat, HOMA- β was improved (p<0.05) after HIIT (267 ± 166 and 183 ± 109, pre- and post-HIIT, respectively). CONCLUSION: HIIT reduces inflammation and improve metabolic parameters in obese insulin sensitive and insulin resistant individuals.Supported by CAPES, CNPq, FAPEMIG