Influence of corticosteroids on myonuclear domain size in the rat diaphragm muscle

A. Jeroen Verheul, Carlos Bernardo Mantilla, Wen Zhi Zhan, Miguel Bernal, P. N Richard Dekhuijzen, Gary C Sieck

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Skeletal muscle fibers are multinucleated. Each myonucleus regulates gene products and protein expression in only a restricted portion of the muscle fiber, the myonuclear domain (MND). In the rat diaphragm muscle (DIAm), corticosteroid (CoS) treatment causes atrophy of fibers containing myosin heavy chain (MHC): MHC2X and/or MHC2B. We hypothesized that DIAm fiber MND size is maintained during CoS-induced atrophy. Adult male rats received methylprednisolone for 11 days at 1 (CoS-Low, n = 8) or 8 mg·kg-1·day-1 (CoS-High, n = 8). Age-matched (CTL-AgeM, n = 8), sham-operated (SHAM-AgeM, n = 8), and weight-matched (CTL-WtM, n = 8) animals served as controls. In single DIAm fibers, cross-sectional area (CSA), MND size, and MHC expression were determined. Fiber CSA and MND size were similar in CTL-AgeM and SHAM-AgeM groups. Only fibers containing MHCslow or MHC2A displayed smaller CSA in CTL-WtM than in CTL-AgeM and SHAM-AgeM groups, and MND size was reduced in all fibers. Thus fibers containing MHCslow and MHC2A maintain the number of myonuclei, whereas MHC2X or MHC2B fibers show loss of myonuclei during normal muscle growth. Both CoS groups displayed smaller CSA and MND size than CTL-AgeM and SHAM-AgeM groups. However, compared with CTL-WtM DIAm fibers, only fibers containing MHC2X or MHC 2B displayed reduced CSA and MND size after CoS treatment. Thus little, if any, loss of myonuclei was associated with CoS-induced atrophy of MHC2X or MHC2B DIAm fibers. In summary, MND size does not appear to be regulated during CoS-induced DIAm atrophy.

Original languageEnglish (US)
Pages (from-to)1715-1722
Number of pages8
JournalJournal of Applied Physiology
Volume97
Issue number5
DOIs
StatePublished - Nov 2004

Fingerprint

Diaphragm
Adrenal Cortex Hormones
Muscles
Myosin Heavy Chains
Atrophy
Muscular Atrophy
Skeletal Muscle Fibers
Methylprednisolone
Weights and Measures
salicylhydroxamic acid
Growth

Keywords

  • Fiber growth
  • Methylprednisolone
  • Muscle atrophy
  • Respiratory muscles
  • Single fiber

ASJC Scopus subject areas

  • Physiology
  • Endocrinology
  • Orthopedics and Sports Medicine
  • Physical Therapy, Sports Therapy and Rehabilitation

Cite this

Influence of corticosteroids on myonuclear domain size in the rat diaphragm muscle. / Verheul, A. Jeroen; Mantilla, Carlos Bernardo; Zhan, Wen Zhi; Bernal, Miguel; Dekhuijzen, P. N Richard; Sieck, Gary C.

In: Journal of Applied Physiology, Vol. 97, No. 5, 11.2004, p. 1715-1722.

Research output: Contribution to journalArticle

Verheul, A. Jeroen ; Mantilla, Carlos Bernardo ; Zhan, Wen Zhi ; Bernal, Miguel ; Dekhuijzen, P. N Richard ; Sieck, Gary C. / Influence of corticosteroids on myonuclear domain size in the rat diaphragm muscle. In: Journal of Applied Physiology. 2004 ; Vol. 97, No. 5. pp. 1715-1722.
@article{91f0234442aa49cc8235abfbb6fa1baf,
title = "Influence of corticosteroids on myonuclear domain size in the rat diaphragm muscle",
abstract = "Skeletal muscle fibers are multinucleated. Each myonucleus regulates gene products and protein expression in only a restricted portion of the muscle fiber, the myonuclear domain (MND). In the rat diaphragm muscle (DIAm), corticosteroid (CoS) treatment causes atrophy of fibers containing myosin heavy chain (MHC): MHC2X and/or MHC2B. We hypothesized that DIAm fiber MND size is maintained during CoS-induced atrophy. Adult male rats received methylprednisolone for 11 days at 1 (CoS-Low, n = 8) or 8 mg·kg-1·day-1 (CoS-High, n = 8). Age-matched (CTL-AgeM, n = 8), sham-operated (SHAM-AgeM, n = 8), and weight-matched (CTL-WtM, n = 8) animals served as controls. In single DIAm fibers, cross-sectional area (CSA), MND size, and MHC expression were determined. Fiber CSA and MND size were similar in CTL-AgeM and SHAM-AgeM groups. Only fibers containing MHCslow or MHC2A displayed smaller CSA in CTL-WtM than in CTL-AgeM and SHAM-AgeM groups, and MND size was reduced in all fibers. Thus fibers containing MHCslow and MHC2A maintain the number of myonuclei, whereas MHC2X or MHC2B fibers show loss of myonuclei during normal muscle growth. Both CoS groups displayed smaller CSA and MND size than CTL-AgeM and SHAM-AgeM groups. However, compared with CTL-WtM DIAm fibers, only fibers containing MHC2X or MHC 2B displayed reduced CSA and MND size after CoS treatment. Thus little, if any, loss of myonuclei was associated with CoS-induced atrophy of MHC2X or MHC2B DIAm fibers. In summary, MND size does not appear to be regulated during CoS-induced DIAm atrophy.",
keywords = "Fiber growth, Methylprednisolone, Muscle atrophy, Respiratory muscles, Single fiber",
author = "Verheul, {A. Jeroen} and Mantilla, {Carlos Bernardo} and Zhan, {Wen Zhi} and Miguel Bernal and Dekhuijzen, {P. N Richard} and Sieck, {Gary C}",
year = "2004",
month = "11",
doi = "10.1152/japplphysiol.00625.2003",
language = "English (US)",
volume = "97",
pages = "1715--1722",
journal = "Journal of Applied Physiology",
issn = "8750-7587",
publisher = "American Physiological Society",
number = "5",

}

TY - JOUR

T1 - Influence of corticosteroids on myonuclear domain size in the rat diaphragm muscle

AU - Verheul, A. Jeroen

AU - Mantilla, Carlos Bernardo

AU - Zhan, Wen Zhi

AU - Bernal, Miguel

AU - Dekhuijzen, P. N Richard

AU - Sieck, Gary C

PY - 2004/11

Y1 - 2004/11

N2 - Skeletal muscle fibers are multinucleated. Each myonucleus regulates gene products and protein expression in only a restricted portion of the muscle fiber, the myonuclear domain (MND). In the rat diaphragm muscle (DIAm), corticosteroid (CoS) treatment causes atrophy of fibers containing myosin heavy chain (MHC): MHC2X and/or MHC2B. We hypothesized that DIAm fiber MND size is maintained during CoS-induced atrophy. Adult male rats received methylprednisolone for 11 days at 1 (CoS-Low, n = 8) or 8 mg·kg-1·day-1 (CoS-High, n = 8). Age-matched (CTL-AgeM, n = 8), sham-operated (SHAM-AgeM, n = 8), and weight-matched (CTL-WtM, n = 8) animals served as controls. In single DIAm fibers, cross-sectional area (CSA), MND size, and MHC expression were determined. Fiber CSA and MND size were similar in CTL-AgeM and SHAM-AgeM groups. Only fibers containing MHCslow or MHC2A displayed smaller CSA in CTL-WtM than in CTL-AgeM and SHAM-AgeM groups, and MND size was reduced in all fibers. Thus fibers containing MHCslow and MHC2A maintain the number of myonuclei, whereas MHC2X or MHC2B fibers show loss of myonuclei during normal muscle growth. Both CoS groups displayed smaller CSA and MND size than CTL-AgeM and SHAM-AgeM groups. However, compared with CTL-WtM DIAm fibers, only fibers containing MHC2X or MHC 2B displayed reduced CSA and MND size after CoS treatment. Thus little, if any, loss of myonuclei was associated with CoS-induced atrophy of MHC2X or MHC2B DIAm fibers. In summary, MND size does not appear to be regulated during CoS-induced DIAm atrophy.

AB - Skeletal muscle fibers are multinucleated. Each myonucleus regulates gene products and protein expression in only a restricted portion of the muscle fiber, the myonuclear domain (MND). In the rat diaphragm muscle (DIAm), corticosteroid (CoS) treatment causes atrophy of fibers containing myosin heavy chain (MHC): MHC2X and/or MHC2B. We hypothesized that DIAm fiber MND size is maintained during CoS-induced atrophy. Adult male rats received methylprednisolone for 11 days at 1 (CoS-Low, n = 8) or 8 mg·kg-1·day-1 (CoS-High, n = 8). Age-matched (CTL-AgeM, n = 8), sham-operated (SHAM-AgeM, n = 8), and weight-matched (CTL-WtM, n = 8) animals served as controls. In single DIAm fibers, cross-sectional area (CSA), MND size, and MHC expression were determined. Fiber CSA and MND size were similar in CTL-AgeM and SHAM-AgeM groups. Only fibers containing MHCslow or MHC2A displayed smaller CSA in CTL-WtM than in CTL-AgeM and SHAM-AgeM groups, and MND size was reduced in all fibers. Thus fibers containing MHCslow and MHC2A maintain the number of myonuclei, whereas MHC2X or MHC2B fibers show loss of myonuclei during normal muscle growth. Both CoS groups displayed smaller CSA and MND size than CTL-AgeM and SHAM-AgeM groups. However, compared with CTL-WtM DIAm fibers, only fibers containing MHC2X or MHC 2B displayed reduced CSA and MND size after CoS treatment. Thus little, if any, loss of myonuclei was associated with CoS-induced atrophy of MHC2X or MHC2B DIAm fibers. In summary, MND size does not appear to be regulated during CoS-induced DIAm atrophy.

KW - Fiber growth

KW - Methylprednisolone

KW - Muscle atrophy

KW - Respiratory muscles

KW - Single fiber

UR - http://www.scopus.com/inward/record.url?scp=7044229641&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=7044229641&partnerID=8YFLogxK

U2 - 10.1152/japplphysiol.00625.2003

DO - 10.1152/japplphysiol.00625.2003

M3 - Article

C2 - 15234958

AN - SCOPUS:7044229641

VL - 97

SP - 1715

EP - 1722

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 5

ER -