Aerobic exercise and weight loss reduce vascular markers of inflammation and improve insulin sensitivity in obese women

Abstract

Objectives: To examine the relationships between plasma and tissue markers of systemic and vascular inflammation and obesity and insulin resistance and determine the effects of aerobic exercise training plus weight loss (AEX+WL) and weight loss (WL) alone on these biomarkers.

Design: Prospective controlled study.

Setting: Veterans Affairs Medical Center and University research setting.

Participants: Overweight and obese sedentary postmenopausal women (N = 77).

Interventions: Six months, 3 d/wk AEX+WL (n = 37) or WL (n = 40).

Measurements: Total-body dual-energy X-ray absorptiometry, abdominal computed tomography, hyperinsulinemic-euglycemic clamps (a criterion standard method of assessing insulin sensitivity), adipose tissue biopsies (n = 28), and blood for homeostasis model assessment-insulin resistance, and soluble forms of intracellular adhesion molecule 1 (sICAM-1) and vascular cell adhesion molecule 1 (sVCAM-1), C-reactive protein (CRP), and serum amyloid A (SAA).

Results: Body weight (P < .001), percentage of fat (P < .001), visceral fat (P < .005), triglyceride levels (P < .001), and systolic blood pressure decreased comparably after WL and AEX+WL (P = .04). Maximal oxygen consumption increased 16% after AEX+WL (P < .001). Insulin resistance decreased in both groups (P = .005). Glucose utilization according to the clamp increased 10% (P = .04) with AEX+WL and 8% with WL (P = .07). AEX+WL decreased CRP by 29% (P < .001) and WL by 21% (P = .02). SAA levels decreased twice as much after AEX+WL (-19%, P = .02) as after WL (-9%, P = .08). Plasma sICAM-1 and sVCAM-1 levels did not change, but women with the greatest reduction in plasma sICAM-1 levels had the greatest reductions in fasting glucose (P = .02), insulin (P = .02), and insulin resistance (P = .004). Gluteal ICAM messenger ribonucleic acid levels decreased 27% after AEX+WL (P = .02) and did not change after WL.

Conclusion: Obesity and insulin resistance worsen markers of systemic and vascular inflammation. A reduction in plasma sICAM-1 is important to improve insulin sensitivity. CRP, SAA, and tissue ICAM decrease with exercise and weight loss, suggesting that exercise training is a necessary component of lifestyle modification in obese postmenopausal women.

Trial registration: ClinicalTrials.gov NCT00882141.

Keywords: diet; exercise; inflammation; insulin sensitivity.

Conflict of interest statement

There are no conflicts of interest.

© Published 2014. This article is a U.S. Government work and is in the public domain in the U.S.A.

Figures

Figure 1

Plasma C-reactive protein (CRP) and acute-phase serum amyloid A (SAA) levels pre and post aerobic exercise +weight loss (AEX+WL) (n=36) and weight loss (WL) (n=40) in postmenopausal women. *P

Figure 2

Plasma intracellular adhesion molecule (sICAM-1) and vascular CAM-1 (sVCAM-1)levels pre and post aerobic exercise +weight loss (AEX+WL) (n=35) and weight loss (WL) (n=40) in postmenopausal women. *P