title: Influence of exercise training and age on CD14+ cell-surface expression of toll-like receptor 2 and 4.
abstract: The influence of an exercise training program and age on inflammatory cytokine production and CD14+cell-surface expression of toll-like receptor 2 (TLR2) and toll-like receptor 4 (TLR4) was examined in 60 younger and older subjects. Subjects were assigned to: young physically active (YPA, n = 15; 25.2 +/- 5.0 years), young physically inactive (YPI, n = 14; 24.9 +/- 4.7 years), older physically active (OPA, n = 14; 71.2 +/- 4.4 years) or older physically inactive (OPI, n = 17; 71.0 +/- 4.3 years) groups. YPI and OPI completed 12 weeks (3 days/week) of endurance (20 min) and resistance exercise (eight exercises, two sets). YPA and OPA groups were instructed to continue their normal activity for 12 weeks. Blood was collected at rest, before and after the 12-week training and control period. A whole blood method was used to determine lipopolysaccharide-(LPS) and peptidoglycan-(PGN) stimulated IL-6, IL-1beta, and TNF-alpha production with supernatants analyzed using ELISA. CD14+ cell-surface expression of TLR2 and TLR4 were measured using flow cytometry. Training increased estimated VO(2max) by 10.4% and increased strength by an average of 38.1%. YPI and OPI had a post-training reduction in LPS-stimulated IL-6 production (P < .01), but LPS-stimulated IL-1beta and TNF-alpha and PGN-stimulated cytokines were not changed. CD14+ cell TLR4 was significantly reduced (P < .05) in YPI and OPI groups after training, but TLR2 was not significantly changed. An exercise training program reduced LPS-stimulated IL-6, concomitant with lower TLR4. These results provide further support for a training- or physical activity-induced lowering of TLR4 and inflammation.
authors.affiliation: Wastl Human Performance Laboratory, Department of Health and Kinesiology, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Laura K
authors.initials: LK
authors.lastname: Stewart
authors.forename: Michael G
authors.initials: MG
authors.lastname: Flynn
authors.forename: Wayne W
authors.initials: WW
authors.lastname: Campbell
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Craig
authors.forename: J Paul
authors.initials: JP
authors.lastname: Robinson
authors.forename: Brian K
authors.initials: BK
authors.lastname: McFarlin
authors.forename: Kyle L
authors.initials: KL
authors.lastname: Timmerman
authors.forename: Paul M
authors.initials: PM
authors.lastname: Coen
authors.forename: Jennifer
authors.initials: J
authors.lastname: Felker
authors.forename: Erin
authors.initials: E
authors.lastname: Talbert
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015308:Anaerobic Threshold / Q000502:physiology; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D005456:Fluorescent Dyes; D006801:Humans; D018950:Lipopolysaccharide Receptors / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008137:Longitudinal Studies; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology; D010457:Peptidoglycan / Q000494:pharmacology; D010807:Physical Endurance / Q000502:physiology; D010809:Physical Fitness / Q000502:physiology*; D011956:Receptors, Cell Surface / Q000096:biosynthesis*; D013268:Stimulation, Chemical; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors; D014891:Weight Lifting / Q000502:physiology
chemical_list: D016207:Cytokines; D005456:Fluorescent Dyes; D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D010457:Peptidoglycan; D011956:Receptors, Cell Surface; C495342:TLR2 protein, human; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors