Simbo, Sunday Yamo (2013-12). Effects of Exercise and Diet- induced Weight Loss in Overweight/Obese Women on Characterization of Serum/White Blood Cells, microRNAs and Cytokine Gene Transcription. Doctoral Dissertation.
Thesis
This study examined the effects of exercise and diet-induced weight loss on markers of inflammation in obese females. Forty-nine obese women (age 48.2+-10.5 years, height 63.5+-2.7cm; weight 203.3+-30.5 kg; BMI 35.6+-5.6 kg/m^(2); 45.9+-4.4 % body fat) completed a 12-week study (exercise group (EX): n=29; control group (C): n=20). Participants followed an energy-restricted diet (1,200 kcal/d for 1-week and 1,500 kcal/d for 11 weeks; 30% CHO, 45% P, and 25% F) while participating in a 30-min circuit resistance-training (3 days/wk) and 30 min walking program on non-workout days. DEXA body composition, fitness, and serum/white blood cells samples were obtained at 0, 4, 8 and 12 wks. The expression of microRNA (21 and 146a) and the expression levels of IL-6, TNF-?, (PTEN, TRAF6)/PI3k/AKT/NF-kB were measured by real-time RT-PCR at 0 and 12 wks. Data were analyzed by MANOVA and presented as changes from baseline after 12 wks for the EX and C groups. Overall MANOVA analysis revealed a significant time effect (p=0.004) and group x time effect (p=0.004) for body composition measures. Participants in the EX group experienced significant changes in body weight (EX -4.0+-4.4 kg; C 0.1+-3.0 kg, p=0.001), fat mass (EX -3.8+-4.0 kg; C -0.03+-2.0 kg, p<0.001), and percent body fat (EX -2.7+-3.4%; C -0.1+-1.7%, p=0.002). Overall MANOVA analysis revealed a significant time effect (p<0.001) and group x time effect (p=0.003) for measures of fitness. Overall significant MANOVA interaction was observed among EX and C groups (Wilks' Lambda p<0.001) on markers of inflammation. Significant interactions were observed among groups in microRNA 21 (EX -1.5+-2.34; C 0.13+-2.2, p=0.03), mRNA expression levels of PTEN (EX -4.5+-3.2; C -1.6+-3.4, p=0.005), IL-6 (EX -2.8+-3.6; C 2.8+-2.2, p=0.00); and, TNF-? (EX -0.52+-2.5; C 2.3+-1.9, p=0.00). Changes in microRNA (21 and 146a) were positively and significantly correlated to body weight, total weight, fat mass, and body fat percent, with circulatory levels of IL-6 and TNF-?. Results indicate that 12-wks of participation in an exercise and weight loss program significantly affects microRNA 21 and its target gene PTEN, mRNA TNF-?, and mRNA IL-6 levels suggesting an anti-inflammatory response compared to a control group.
