Functional muscle hypertrophy by increased insulin‐like growth factor 1 does not require dysferlin

Authors:
Open Access
Publisher website
Google Scholar
Abstract
Introduction: Dysferlin loss‐of‐function mutations cause muscular dystrophy, accompanied by impaired membrane repair and muscle weakness. Growth promoting strategies including insulin‐like growth factor 1 (IGF‐1) could provide benefit but may cause strength loss or be ineffective. The objective of this study was to determine whether locally increased IGF‐1 promotes functional muscle hypertrophy in dysferlin‐null (Dysf−/−) mice.Methods: Muscle‐specific transgenic expression and postnatal viral delivery of Igf1 were used in Dysf−/− and control mice. Increased IGF‐1 levels were confirmed by enzyme‐linked immunosorbent assay. Testing for skeletal muscle mass and function was performed in male and female mice.Results: Muscle hypertrophy occurred in response to increased IGF‐1 in mice with and without dysferlin. Male mice showed a more robust response compared with females. Increased IGF‐1 did not cause loss of force per cross‐sectional area in Dysf−/− muscles.Discussion: We conclude that increased local IGF‐1 promotes functional hypertrophy when dysferlin is absent and reestablishes IGF‐1 as a potential therapeutic for dysferlinopathies.
Funding Information
  • National Institutes of Health (AR052646)

This publication has 43 references indexed in Scilit: