TY - JOUR
T1 - Growth Hormone Therapy Accelerates Axonal Regeneration, Promotes Motor Reinnervation, and Reduces Muscle Atrophy following Peripheral Nerve Injury
AU - Tuffaha, Sami H.
AU - Budihardjo, Joshua D.
AU - Sarhane, Karim A.
AU - Khusheim, Mohammed
AU - Song, Diana
AU - Broyles, Justin M.
AU - Salvatori, Roberto
AU - Means, Kenneth R.
AU - Higgins, James P.
AU - Shores, Jaimie T.
AU - Cooney, Damon S.
AU - Hoke, Ahmet
AU - Lee, W. P.Andrew
AU - Brandacher, Gerald
N1 - Publisher Copyright:
© Copyright 2016 by the American Society of Plastic Surgeons.
PY - 2016/6/1
Y1 - 2016/6/1
N2 - Background: Therapies to improve outcomes following peripheral nerve injury are lacking. Prolonged denervation of muscle and Schwann cells contributes to poor outcomes. In this study, the authors assess the effects of growth hormone therapy on axonal regeneration, Schwann cell and muscle maintenance, and end-organ reinnervation in rats. Methods: Male Sprague-Dawley rats underwent sciatic nerve transection and repair and femoral nerve transection without repair and received either daily subcutaneous growth hormone (0.4 mg/day) or no treatment (n = 8 per group). At 5 weeks, the authors assessed axonal regeneration within the sciatic nerve, muscle atrophy within the gastrocnemius muscle, motor endplate reinnervation within the soleus muscle, and Schwann cell proliferation within the denervated distal femoral nerve. Results: Growth hormone-treated animals demonstrated greater percentage increase in body mass (12.2 ± 1.8 versus 8.5 ± 1.5; p = 0.0044), greater number of regenerating myelinated axons (13,876 ± 2036 versus 8645 ± 3279; p = 0.0018) and g-ratio (0.64 ± 0.11 versus 0.51 ± 0.06; p = 0.01), greater percentage reinnervation of motor endplates (75.8 ± 8.7 versus 38.2 ± 22.6; p = 0.0008), and greater muscle myofibril cross-sectional area (731.8 ± 157 μm versus 545.2 ± 144.3 μm; p = 0.027). Conclusions: In male rats, growth hormone therapy accelerates axonal regeneration, reduces muscle atrophy, and promotes muscle reinnervation. Growth hormone therapy may also maintain proliferating Schwann cells in the setting of prolonged denervation. These findings suggest potential for improved outcomes with growth hormone therapy after peripheral nerve injuries.
AB - Background: Therapies to improve outcomes following peripheral nerve injury are lacking. Prolonged denervation of muscle and Schwann cells contributes to poor outcomes. In this study, the authors assess the effects of growth hormone therapy on axonal regeneration, Schwann cell and muscle maintenance, and end-organ reinnervation in rats. Methods: Male Sprague-Dawley rats underwent sciatic nerve transection and repair and femoral nerve transection without repair and received either daily subcutaneous growth hormone (0.4 mg/day) or no treatment (n = 8 per group). At 5 weeks, the authors assessed axonal regeneration within the sciatic nerve, muscle atrophy within the gastrocnemius muscle, motor endplate reinnervation within the soleus muscle, and Schwann cell proliferation within the denervated distal femoral nerve. Results: Growth hormone-treated animals demonstrated greater percentage increase in body mass (12.2 ± 1.8 versus 8.5 ± 1.5; p = 0.0044), greater number of regenerating myelinated axons (13,876 ± 2036 versus 8645 ± 3279; p = 0.0018) and g-ratio (0.64 ± 0.11 versus 0.51 ± 0.06; p = 0.01), greater percentage reinnervation of motor endplates (75.8 ± 8.7 versus 38.2 ± 22.6; p = 0.0008), and greater muscle myofibril cross-sectional area (731.8 ± 157 μm versus 545.2 ± 144.3 μm; p = 0.027). Conclusions: In male rats, growth hormone therapy accelerates axonal regeneration, reduces muscle atrophy, and promotes muscle reinnervation. Growth hormone therapy may also maintain proliferating Schwann cells in the setting of prolonged denervation. These findings suggest potential for improved outcomes with growth hormone therapy after peripheral nerve injuries.
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U2 - 10.1097/PRS.0000000000002188
DO - 10.1097/PRS.0000000000002188
M3 - Article
C2 - 26890510
AN - SCOPUS:84958818060
SN - 0032-1052
VL - 137
SP - 1771
EP - 1780
JO - Plastic and reconstructive surgery
JF - Plastic and reconstructive surgery
IS - 6
ER -