Effects of nandrolone on denervation atrophy depend upon time after nerve transection.
Anabolic steroids prevent disuse atrophy and reverse atrophy caused by glucocorticoids. To determine whether these beneficial effects extend to denervation atrophy, we tested whether nandrolone blocked denervation atrophy acutely or reversed subacute denervation atrophy. We also tested the association of such anabolic effects with expression of MAFbx, MuRF1 (both of which accelerate denervation atrophy), and IGF-1 (which prevents such atrophy). When begun at the time of denervation, nandrolone did not alter atrophy or expression of MAFbx, MuRF1, or IGF-1 measured 3, 7, or 14 days thereafter. When nandrolone administration was begun 28 days after denervation, atrophy was significantly reduced 7 and 28 days later (16% and 30%, respectively), and this was associated with significant reductions in expression of MAFbx and MuRF1, without alterations in the expression of IGF-1. The findings indicate that the actions of nandrolone depend on time after nerve transection and that the timing of anabolic steroid administration is an important determinant of responses of atrophying muscle to these agents.
Zhao
Jingbo
J
Department of Veterans Affairs, Room 1E-02, James J. Peters VA Medical Center, Bronx, New York 10468, USA.
Zhang
Yuangfei
Y
Zhao
Weidong
W
Wu
Yong
Y
Pan
Jiangping
J
Bauman
William A
WA
Cardozo
Christopher
C
D045930:Anabolic Agents / Q000494:pharmacology*; D000818:Animals; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D008297:Male; D009121:Muscle Denervation; D009124:Muscle Proteins / Q000187:drug effects / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000378:metabolism* / Q000503:physiopathology; D009133:Muscular Atrophy / Q000188:drug therapy* / Q000378:metabolism* / Q000503:physiopathology; D018008:Myogenin / Q000378:metabolism; D009277:Nandrolone / Q000494:pharmacology*; D059348:Peripheral Nerve Injuries; D010525:Peripheral Nerves / Q000503:physiopathology; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D017526:Receptor, IGF Type 1 / Q000378:metabolism; D044843:SKP Cullin F-Box Protein Ligases / Q000378:metabolism; D013997:Time Factors; D000070584:Tripartite Motif Proteins; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism; D000097642:GADD45 Proteins
D045930:Anabolic Agents; D007334:Insulin-Like Growth Factor I; D047908:Intracellular Signaling Peptides and Proteins; D009124:Muscle Proteins; D018008:Myogenin; D009277:Nandrolone; D016755:Proto-Oncogene Proteins c-jun; D017526:Receptor, IGF Type 1; D044843:SKP Cullin F-Box Protein Ligases; D000070584:Tripartite Motif Proteins; D044767:Ubiquitin-Protein Ligases; D000097642:GADD45 Proteins; C486692:Fbxo32 protein, rat; C499086:Trim63 protein, rat