| Autor: |
McHale MJ; Department of Surgery, University of Texas Health Science Center, San Antonio, USA., Sarwar ZU, Cardenas DP, Porter L, Salinas AS, Michalek JE, McManus LM, Shireman PK |
| Jazyk: |
angličtina |
| Zdroj: |
American journal of physiology. Regulatory, integrative and comparative physiology [Am J Physiol Regul Integr Comp Physiol] 2012 Feb 01; Vol. 302 (3), pp. R331-9. Date of Electronic Publication: 2011 Nov 23. |
| DOI: |
10.1152/ajpregu.00427.2011 |
| Abstrakt: |
Sex differences in skeletal muscle regeneration are controversial; comparisons of regenerative events between sexes have not been rigorously defined in severe injury models. We comprehensively quantified inflammation and muscle regeneration between sexes and manipulated sex-specific hormones to determine effects on regeneration. Cardiotoxin injury was induced in intact, castrated and ovariectomized female and male mice; ovariectomized mice were replaced with low- or high-dose 17-β estradiol (E(2)) or progesterone (P4). Extent of injury was comparable between intact mice, but females were more efficient in removal of necrotic debris, despite similar tissue levels of inflammatory cells and chemokines. Myofiber size during regeneration was equivalent between intact mice and after castration or ovariectomy (OVX) but was decreased (P < 0.001) in ovariectomized mice with high-dose E(2) replacement. Intermuscular adipocytes were absent in uninjured muscle, whereas adipocyte area was increased among regenerated myofibers in all groups. Interestingly, intermuscular fat was greater (P = 0.03) in intact females at day 14 compared with intact males. Furthermore, castration increased (P = 0.01) and OVX decreased adipocyte accumulation. After OVX, E(2), but not P4, replacement decreased (P ≤ 0.03) fat accumulation. In conclusion, sex-dependent differences in regeneration consisted of more efficient removal of necrosis and increased fat deposition in females with similar injury, inflammation, and regenerated myofiber size; high-dose E(2) decreased myofiber size and fat deposition. Adipocyte accumulation in regenerating muscle was influenced by sex-specific hormones. Recovery following muscle injury was different between males and females, and sex-specific hormones contributed to these differences, suggesting that sex-specific treatments could be beneficial after injury. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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