Effects of Exercise and Omega-3-Supplemented, High-Protein Diet on Inflammatory Markers in Serum, on Gene Expression Levels in PBMC, and after Ex Vivo Whole-Blood LPS Stimulation in Old Adults

Abstract

Inflammaging is related to cell senescence and reflects an erratic immune system, which promotes age-associated diseases. Exercise and nutrition, particularly omega-3 fatty acids, are able to affect inflammation. Therefore, we examined the effects of an 8-week exercise and dietary intervention on the inflammatory response in community-dwelling old adults. All participants received weekly vibration and home-based resistance exercise. Furthermore, participants were randomized to either a control, high-protein (1.2–1.5 g/kg), or high-protein, omega-3-enriched (2.2 g/day) diet. Before and after treatment, inflammatory markers in fasting serum and after whole-blood ex vivo lipopolysaccharide (LPS) stimulation were assessed. Gene expression levels of inflammatory markers were quantified in peripheral blood mononuclear cells (PBMC). Sixty-one participants (age: 70.6 ± 4.7 years; 47% men) completed the study. According to generalized linear mixed models, a high-protein, omega-3-enriched diet decreased circulating anti-inflammatory interleukin (IL-) 10 and IL-1 receptor antagonist (IL-1RA). Sex-stratified analyses showed also significantly reduced pro-inflammatory markers in men with a high-protein, omega-3-enriched diet. Gene expression of IL-1RA was significantly reduced after both protein-enriched diets compared with controls. In comparison to a high-protein diet, exercise alone showed lower LPS-induced release of c-c motif chemokine ligand-2 (CCL-2), which tended to be more pronounced in men compared with women. Eight weeks of a high-protein, omega-3-enriched diet combined with exercise decreased circulating anti-inflammatory markers, and pro-inflammatory markers in men. A high-protein diet attenuated anti-inflammatory markers on gene expression level in PBMC. Exercise alone resulted in a lower pro-inflammatory response to LPS-exposure in whole-blood cultures.