Exercise, inflammation and vascular function in aging and obesity.

Background. While aging is a non-modifiable process, obesity is a reversible condition. However, both are characterized by a low-grade inflammatory profile and vascular dysfunction. Exercise is a non-pharmacological strategy able to counteract the negative effect of aging as well as of obesity. Nonetheless, its short-term and long-term effect on inflammation and vascular function in obese and non-obese elderly individuals are still matter of debate. Still not clear are the differences in the acute inflammatory and vascular response to different types and intensities of exercise in sedentary subjects. Aims. The primary aim was to examine how the inflammatory profile and vascular function in non-obese and obese elderly individuals is affected. A secondary aim was to understand the acute inflammatory and vascular response to different exercise types (i.e. aerobic, A; resistance, R) and intensity (i.e. high, H; low, L) in sedentary obese individuals (OB) compared with normal weight (NW) subjects. Methods. Seventy individuals who attended a structured exercise program (30/40f/m; 75±5 years; 5±2 years of regular training) were enrolled in study 1 and tested for vascular function (flow-mediated dilation; FMD) and inflammatory profile (plasma CRP, IL-1β, IL-1ra, IL-6, IL-8, IL-10, TNF-, MCP-1). Subjects were stratified for age and BMI. Correlations between age, BMI and the measured variables were investigated. In study 2, still ongoing, 5 NW (54±7 years; 24.2±0.7 BMI) and 5 OB (53±6years; 33.7±1.2 BMI) subjects were included and tested for FMD and inflammatory profile before and after 4 different exercise sessions. Results. In study 1 inverse correlations were found between age and IL- β (r -0.232; p<.05); IL-1ra (r -0.181; p<.05); IL-6 (r -0.255; p<.05); and IL-8 (r -0.248; p<.05). Direct correlations were found between BMI and CRP (r 0.155; p<.05), MCP-1 (r 0.217; p<.05); and TNF- (r 0.184; p<.05). An inverse correlation was also found between BMI and FMD (r -0.433; p<.01). In a preliminary analysis of data of study 2, different types and intensities of exercise seem to elicite different acute inflammatory responses in NW and OB. However, most differences did not reach statistical significance. FMD showed a significant increase in the post exercise period for all the 4 exercise sessions in both groups (p<.05) with smaller increases in OB as compared with NW. No significant differences between exercise sessions were found. Conclusion. Sustained, regular exercise can counteract the deleterious effects of aging but not of obesity on vascular function and inflammatory profile. Preliminary results of study 2 lead us to speculate that exercise, both aerobic and resistance exercise as well as both high and low intensity, do not seem to affect adversely the inflammatory profile and the acute vascular response in either obese or non-obese individuals. However, further research is needed to confirm these findings.