BACKGROUND: Human aging is characterized by a chronic, low-grade inflammation suspected to contribute to reductions in skeletal muscle size, strength, and function. Inflammatory cytokines, such as interleukin-6 (IL-6), may play a role in the reduced skeletal muscle adaptive response seen in older individuals. OBJECTIVES: To investigate relationships between circulating IL-6, skeletal muscle health and exercise adaptation in mobility-limited older adults. DESIGN: Randomized controlled trial. SETTING: Exercise laboratory on the Health Sciences campus of an urban university. PARTICIPANTS: 99 mobility-limited (Short Physical Performance Battery (SPPB) ≤9) older adults. INTERVENTION: 6-month structured physical activity with or without a protein and vitamin D nutritional supplement. MEASUREMENTS: Circulating IL-6, skeletal muscle size, composition (percent normal density muscle tissue), strength, power, and specific force (strength/CSA) as well as physical function (gait speed, stair climb time, SPPB-score) were measured pre- and post-intervention. RESULTS: At baseline, Spearman's correlations demonstrated an inverse relationship (P<0.05) between circulating IL-6 and thigh muscle composition (r = -0.201), strength (r = -0.311), power (r = -0.210), and specific force (r = -0.248), and positive association between IL-6 and stair climb time (r = 0.256; P<0.05). Although the training program did not affect circulating IL-6 levels (P=0.69), reductions in IL-6 were associated with gait speed improvements (r = -0.487; P<0.05) in "higher" IL-6 individuals (>1.36 pg/ml). Moreover, baseline IL-6 was inversely associated (P<0.05) with gains in appendicular lean mass and improvements in SPPB score (r = -0.211 and -0.237, respectively). CONCLUSIONS: These findings implicate age-related increases in circulating IL-6 as an important contributor to declines in skeletal muscle strength, quality, function, and training-mediated adaptation. Given the pervasive nature of inflammation among older adults, novel therapeutic strategies to reduce IL-6 as a means of preserving skeletal muscle health are enticing.
RCT Entities:
BACKGROUND:Human aging is characterized by a chronic, low-grade inflammation suspected to contribute to reductions in skeletal muscle size, strength, and function. Inflammatory cytokines, such as interleukin-6 (IL-6), may play a role in the reduced skeletal muscle adaptive response seen in older individuals. OBJECTIVES: To investigate relationships between circulating IL-6, skeletal muscle health and exercise adaptation in mobility-limited older adults. DESIGN: Randomized controlled trial. SETTING: Exercise laboratory on the Health Sciences campus of an urban university. PARTICIPANTS: 99 mobility-limited (Short Physical Performance Battery (SPPB) ≤9) older adults. INTERVENTION: 6-month structured physical activity with or without a protein and vitamin D nutritional supplement. MEASUREMENTS: Circulating IL-6, skeletal muscle size, composition (percent normal density muscle tissue), strength, power, and specific force (strength/CSA) as well as physical function (gait speed, stair climb time, SPPB-score) were measured pre- and post-intervention. RESULTS: At baseline, Spearman's correlations demonstrated an inverse relationship (P<0.05) between circulating IL-6 and thigh muscle composition (r = -0.201), strength (r = -0.311), power (r = -0.210), and specific force (r = -0.248), and positive association between IL-6 and stair climb time (r = 0.256; P<0.05). Although the training program did not affect circulating IL-6 levels (P=0.69), reductions in IL-6 were associated with gait speed improvements (r = -0.487; P<0.05) in "higher" IL-6 individuals (>1.36 pg/ml). Moreover, baseline IL-6 was inversely associated (P<0.05) with gains in appendicular lean mass and improvements in SPPB score (r = -0.211 and -0.237, respectively). CONCLUSIONS: These findings implicate age-related increases in circulating IL-6 as an important contributor to declines in skeletal muscle strength, quality, function, and training-mediated adaptation. Given the pervasive nature of inflammation among older adults, novel therapeutic strategies to reduce IL-6 as a means of preserving skeletal muscle health are enticing.
Authors: Ewa Aleksandra Rodziewicz-Flis; Małgorzata Kawa; Damian Józef Flis; Marzena Szaro-Truchan; Wojciech Romuald Skrobot; Jan Jacek Kaczor Journal: Front Physiol Date: 2022-04-20 Impact factor: 4.755
Authors: Ryan McGrath; Grant R Tomkinson; Brian C Clark; Peggy M Cawthon; Matteo Cesari; Soham Al Snih; Donald A Jurivich; Kyle J Hackney Journal: J Am Med Dir Assoc Date: 2021-06-21 Impact factor: 4.669
Authors: Anna Kurowska; Iwona Bodys-Cupak; Magdalena Staszkiewicz; Joanna Szklarczyk; Joanna Zalewska-Puchała; Anna Kliś-Kalinowska; Marta Makara-Studzińska; Anna Majda Journal: Int J Environ Res Public Health Date: 2020-05-21 Impact factor: 3.390
Authors: Naim M Maalouf; Avneesh Chhabra; Jason Zafereo; Ross Querry; Dwight A Towler; Uma J Thakur; Joseph Frankl; John R Poindexter; Bayan Mogharrabi; May Xac; Orhan K Öz; Craig D Rubin Journal: JBMR Plus Date: 2021-11-15