2021 Volume No 42 – pages 72-89
Title: Muscle insulin-like growth factor-I modulates murine craniofacial bone growth |
Authors: HJ Kok, CN Crowder, L Koo Min Chee, HY Choi, N Lin, ER Barton |
Address: Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, 1864 Stadium Road, Gainesville, FL 32611, USA |
E-mail: erbarton at ufl.edu
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Abstract: Insulin-like growth factor I (IGF-I) is essential for muscle and bone development and a primary mediator of growth hormone (GH) actions. While studies have elucidated the importance of IGF-I specifically in muscle or bone development, few studies to date have evaluated the relationship between muscle and bone modulated by IGF-I in vivo, during post-natal growth. Mice with muscle-specific IGF-I overexpression (mIgf1+/+) were utilised to determine IGF-I- and muscle-mass-dependent effects on craniofacial skeleton development during post-natal growth. mIgf1+/+ mice displayed accelerated craniofacial bone growth when compared to wild-type animals. Virus-mediated expression of IGF-I targeting the masseter was performed to determine if post-natal modulation of IGF-I altered mandibular structures. Increased IGF-I in the masseter affected the mandibular base plane angle in a lateral manner, increasing the width of the mandible. At the cellular level, increased muscle IGF-I also accelerated cartilage thickness in the mandibular condyle. Importantly, mandibular length changes associated with increased IGF-I were not present in mice with genetic inhibition of muscle IGF-I receptor activity. These results demonstrated that muscle IGF-I could indirectly affect craniofacial growth through IGF-I-dependent increases in muscle hypertrophy. These findings have clinical implications when considering IGF-I as a therapeutic strategy for craniofacial disorders. |
Key Words: Muscle-bone interaction, insulin-like growth factor I, craniofacial, bone development. |
Publication date: July 19th 2021 |
Article download: Pages 72-89 (PDF file) |
