Forskning
Udskriv Udskriv
Switch language
Region Hovedstaden - en del af Københavns Universitetshospital
Udgivet

Skeletal muscle morphology and regulatory signalling in endurance-trained and sedentary individuals: The influence of ageing

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Harvard

APA

CBE

MLA

Vancouver

Author

Bibtex

@article{686c046cc38442f8987e4edf1b1d920b,
title = "Skeletal muscle morphology and regulatory signalling in endurance-trained and sedentary individuals: The influence of ageing",
abstract = "Muscle mass in humans is inversely associated with circulating levels of inflammatory cytokines, but the interaction between ageing and training on muscle composition and the intra-muscular signalling behind inflammation and contractile protein synthesis and degradation is unknown. We studied 15 healthy life-long endurance runners, 12 age-matched untrained controls, 10 young trained and 12 young untrained individuals. Thigh muscle composition was investigated by magnetic resonance imaging (MRI), where non-contractile intramuscular tissue (NCIT) area (fat and connective tissue) was found to be greater in older but lower in trained individuals. Subcutaneous adipose tissue was also lower in trained individuals but was not affected by age. In vastus lateralis biopsies, no influence of age or training was found on levels of endomysial collagen, determined by Sirius Red and Collagen III staining, whereas perimysial organisation tended to be more complex in older individuals. No clear difference with training was seen on intramuscular inflammatory signalling, whereas lower protein levels of NFkB subunits p105, p50 and p65 were observed with ageing. Gene expression of IL6 and TNFα was not different between groups, while IL1-receptor and TNFα-receptor1 levels were lower with age. Myostatin mRNA was lower in older and trained groups, while expression of MuRF1 was lower in trained individuals and FoxO3 expression was greater in aged groups. The association of increased muscle NCIT with age-associated muscle loss in humans is not accompanied by any major alterations in intramuscular signalling for inflammation, but rather by direct regulatory factors for protein synthesis and proteolysis in skeletal muscle.",
keywords = "Journal Article, Research Support, Non-U.S. Gov't",
author = "Mikkelsen, {U R} and J Agergaard and C Coupp{\'e} and Grosset, {J F} and A Karlsen and Magnusson, {S P} and P Schjerling and M Kjaer and Mackey, {A L}",
note = "Copyright {\circledC} 2017 Elsevier Inc. All rights reserved.",
year = "2017",
month = "7",
doi = "10.1016/j.exger.2017.04.001",
language = "English",
volume = "93",
pages = "54--67",
journal = "Experimental Gerontology",
issn = "0531-5565",
publisher = "Elsevier Inc",

}

RIS

TY - JOUR

T1 - Skeletal muscle morphology and regulatory signalling in endurance-trained and sedentary individuals

T2 - The influence of ageing

AU - Mikkelsen, U R

AU - Agergaard, J

AU - Couppé, C

AU - Grosset, J F

AU - Karlsen, A

AU - Magnusson, S P

AU - Schjerling, P

AU - Kjaer, M

AU - Mackey, A L

N1 - Copyright © 2017 Elsevier Inc. All rights reserved.

PY - 2017/7

Y1 - 2017/7

N2 - Muscle mass in humans is inversely associated with circulating levels of inflammatory cytokines, but the interaction between ageing and training on muscle composition and the intra-muscular signalling behind inflammation and contractile protein synthesis and degradation is unknown. We studied 15 healthy life-long endurance runners, 12 age-matched untrained controls, 10 young trained and 12 young untrained individuals. Thigh muscle composition was investigated by magnetic resonance imaging (MRI), where non-contractile intramuscular tissue (NCIT) area (fat and connective tissue) was found to be greater in older but lower in trained individuals. Subcutaneous adipose tissue was also lower in trained individuals but was not affected by age. In vastus lateralis biopsies, no influence of age or training was found on levels of endomysial collagen, determined by Sirius Red and Collagen III staining, whereas perimysial organisation tended to be more complex in older individuals. No clear difference with training was seen on intramuscular inflammatory signalling, whereas lower protein levels of NFkB subunits p105, p50 and p65 were observed with ageing. Gene expression of IL6 and TNFα was not different between groups, while IL1-receptor and TNFα-receptor1 levels were lower with age. Myostatin mRNA was lower in older and trained groups, while expression of MuRF1 was lower in trained individuals and FoxO3 expression was greater in aged groups. The association of increased muscle NCIT with age-associated muscle loss in humans is not accompanied by any major alterations in intramuscular signalling for inflammation, but rather by direct regulatory factors for protein synthesis and proteolysis in skeletal muscle.

AB - Muscle mass in humans is inversely associated with circulating levels of inflammatory cytokines, but the interaction between ageing and training on muscle composition and the intra-muscular signalling behind inflammation and contractile protein synthesis and degradation is unknown. We studied 15 healthy life-long endurance runners, 12 age-matched untrained controls, 10 young trained and 12 young untrained individuals. Thigh muscle composition was investigated by magnetic resonance imaging (MRI), where non-contractile intramuscular tissue (NCIT) area (fat and connective tissue) was found to be greater in older but lower in trained individuals. Subcutaneous adipose tissue was also lower in trained individuals but was not affected by age. In vastus lateralis biopsies, no influence of age or training was found on levels of endomysial collagen, determined by Sirius Red and Collagen III staining, whereas perimysial organisation tended to be more complex in older individuals. No clear difference with training was seen on intramuscular inflammatory signalling, whereas lower protein levels of NFkB subunits p105, p50 and p65 were observed with ageing. Gene expression of IL6 and TNFα was not different between groups, while IL1-receptor and TNFα-receptor1 levels were lower with age. Myostatin mRNA was lower in older and trained groups, while expression of MuRF1 was lower in trained individuals and FoxO3 expression was greater in aged groups. The association of increased muscle NCIT with age-associated muscle loss in humans is not accompanied by any major alterations in intramuscular signalling for inflammation, but rather by direct regulatory factors for protein synthesis and proteolysis in skeletal muscle.

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1016/j.exger.2017.04.001

DO - 10.1016/j.exger.2017.04.001

M3 - Journal article

VL - 93

SP - 54

EP - 67

JO - Experimental Gerontology

JF - Experimental Gerontology

SN - 0531-5565

ER -

ID: 52333824