Normal Skeletal Muscle Growth and Function Require Insulin Receptors Expressed by Cholinergic Motor Neurons

Abstract

It is well known that insulin stimulates skeletal muscle growth. However, it is currently unknown how insulin does so since it was previously shown that insulin receptors expressed by skeletal muscles are dispensable in this regard. In this study, we focused on insulin receptors expressed by the cholinergic motor neurons and generated conditional knockout mice which lack insulin receptors specifically in the cholinergic neurons. We found that insulin activates cholinergic motor neurons and that insulin receptors expressed by the cholinergic neurons are required for normal growth of skeletal muscle. We also noted that the conditional knockout mice have underdeveloped neuromuscular junction and compromised skeletal muscle function. Together, our study suggests that insulin stimulates and activates cholinergic motor neurons to promote normal skeletal muscle growth and function. This work was supported by the National Research Foundation of Korea (NRF-2022R1A2C3005613 to Jong-Woo Sohn) funded by the Korean Ministry of Science and ICT. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.