Cytokine response to acute and chronic resistance exercise in women aged 65–85 yr
Abstract
To examine the influence of acute and chronic resistance exercise (RE) on cytokine production in postmenopausal women, 35 women (72 ± 6.2 yr) underwent a moderate- to high-intensity 10-week resistance training program or served as sedentary controls (n = 7). The women were assigned to one of 4 groups: no estrogen replacement (NHR, n = 8), estrogen replacement (HRT, n = 12), selective estrogen receptor modulator (SER, n = 8), or control (non-exercise, no estrogen replacement, CON, n = 7). After a one-week acclimation to RE, NHR, HRT, and SER performed 3 sets of 10 resistance exercises at 80% of their estimated 1 repetition maximum (1RM) before (BT) and after (AT) the 10-week training period. The CON sat quietly in the lab during these experimental trials. Blood samples were collected pre-exercise (PR), immediately post-exercise (PO), and two hours (2H) post-exercise, or at the same time points for CON. Whole blood was diluted 1:10 in RPMI and incubated (37°C, 5%CO2) for 24 hours with lipopolysaccharide (LPS, salmonella enteriditis, 25 μg/ml final concentration). Supernatant and serum were analyzed for the inflammatory cytokines IL-6, IL-1β, and TNF-α using ELISA. Resistance training increased 8RM strength by an average of 30% for 10 exercises. Baseline (BT, PR) mitogen stimulated IL-6 production was greater in SER compared to NHR and CON (11,991, 7608, 7934 pg·ml−1, respectively; p = 0.021). When expressed per monocyte there was no acute exercise effect for stimulated IL-6 or TNF-α production. Stimulated IL-1β production per monocyte was significantly elevated at 2H for the exercise groups collapsed (p < 0.01) and there was a trend for IL-1β to be elevated at 2H for CON (p = 0.095). Resistance training reduced stimulated IL-6, IL-1β, and TNF-α production per monocyte for exercise groups collapsed (p < 0.001). Serum IL-6 was elevated FO in the exercise groups (p = 0.001); and serum TNF-α was decreased after resistance training (p = 0.026). Acute resistance exercise elevated serum IL-6 concentration, whereas resistance training decreased stimulated production of IL-6, IL-1β and TNF-α when expressed per monocyte. The extended elevation of IL-1β at 2H in the exercise groups may be partially explained by a potential circadian response observed in non-exercise CON.
Degree
Ph.D.
Advisors
Flynn, Purdue University.
Subject Area
Sports medicine|Gerontology
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