The Tocotrienol-Rich Fraction Is Superior to Tocopherol in Promoting Myogenic Differentiation in the Prevention of Replicative Senescence of Myoblasts

PLoS One. 2016 Feb 17;11(2):e0149265. doi: 10.1371/journal.pone.0149265. eCollection 2016.

Abstract

Aging results in a loss of muscle mass and strength. Myoblasts play an important role in maintaining muscle mass through regenerative processes, which are impaired during aging. Vitamin E potentially ameliorates age-related phenotypes. Hence, this study aimed to determine the effects of the tocotrienol-rich fraction (TRF) and α-tocopherol (ATF) in protecting myoblasts from replicative senescence and promoting myogenic differentiation. Primary human myoblasts were cultured into young and senescent stages and were then treated with TRF or ATF for 24 h, followed by an analysis of cell proliferation, senescence biomarkers, cellular morphology and differentiation. Our data showed that replicative senescence impaired the normal regenerative processes of myoblasts, resulting in changes in cellular morphology, cell proliferation, senescence-associated β-galactosidase (SA-β-gal) expression, myogenic differentiation and myogenic regulatory factors (MRFs) expression. Treatment with both TRF and ATF was beneficial to senescent myoblasts in reclaiming the morphology of young cells, improved cell viability and decreased SA-β-gal expression. However, only TRF treatment increased BrdU incorporation in senescent myoblasts, as well as promoted myogenic differentiation through the modulation of MRFs at the mRNA and protein levels. MYOD1 and MYOG gene expression and myogenin protein expression were modulated in the early phases of myogenic differentiation. In conclusion, the tocotrienol-rich fraction is superior to α-tocopherol in ameliorating replicative senescence-related aberration and promoting differentiation via modulation of MRFs expression, indicating vitamin E potential in modulating replicative senescence of myoblasts.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Biomarkers / metabolism
  • Bromodeoxyuridine / metabolism
  • Cell Differentiation / drug effects*
  • Cell Differentiation / genetics
  • Cell Proliferation / drug effects
  • Cell Shape / drug effects
  • Cell Survival
  • Cellular Senescence / drug effects*
  • Cellular Senescence / genetics
  • Desmin / metabolism
  • Female
  • Free Radicals / metabolism
  • Humans
  • Male
  • Muscle Development / drug effects*
  • Myoblasts / cytology*
  • Myoblasts / drug effects
  • Myogenic Regulatory Factors / genetics
  • Myogenic Regulatory Factors / metabolism
  • Phenotype
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Tocopherols / pharmacology*
  • Tocotrienols / pharmacology*
  • Vitamin E / pharmacology
  • beta-Galactosidase / metabolism

Substances

  • Biomarkers
  • Desmin
  • Free Radicals
  • Myogenic Regulatory Factors
  • RNA, Messenger
  • Tocotrienols
  • Vitamin E
  • beta-Galactosidase
  • Bromodeoxyuridine
  • Tocopherols

Grants and funding

This study was funded by the Universiti Kebangsaan Malaysia grants AP-2012-012 and UKM-FF-2013-259. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.