» Articles » PMID: 39131310

Genetic Deletion of Skeletal Muscle Inositol Polyphosphate Multikinase Disrupts Glucose Homeostasis and Impairs Exercise Tolerance

Overview
Journal bioRxiv
Date 2024 Aug 12
PMID 39131310
Authors
Affiliations
Soon will be listed here.
Abstract

Inositol phosphates are critical signaling messengers involved in a wide range of biological pathways in which inositol polyphosphate multikinase (IPMK) functions as a rate-limiting enzyme for inositol polyphosphate metabolism. IPMK has been implicated in cellular metabolism, but its function at the systemic level is still poorly understood. Since skeletal muscle is a major contributor to energy homeostasis, we have developed a mouse model in which skeletal muscle IPMK is specifically deleted and examined how a loss of IPMK affects whole-body metabolism. Here, we report that mice in which IPMK knockout is deleted, specifically in the skeletal muscle, displayed an increased body weight, disrupted glucose tolerance, and reduced exercise tolerance under the normal diet. Moreover, these changes were associated with an increased accumulation of triglyceride in skeletal muscle. Furthermore, we have confirmed that a loss of IPMK led to reduced beta-oxidation, increased triglyceride accumulation, and impaired insulin response in IPMK-deficient muscle cells. Thus, our results suggest that IPMK mediates the whole-body metabolism via regulating muscle metabolism and may be potentially targeted for the treatment of metabolic syndromes.

References
1.
Tu-Sekine B, Padhi A, Jin S, Kalyan S, Singh K, Apperson M . Inositol polyphosphate multikinase is a metformin target that regulates cell migration. FASEB J. 2019; 33(12):14137-14146. PMC: 6894044. DOI: 10.1096/fj.201900717RR. View

2.
Hatch A, York J . SnapShot: Inositol phosphates. Cell. 2010; 143(6):1030-1030.e1. PMC: 4299573. DOI: 10.1016/j.cell.2010.11.045. View

3.
Garcia D, Shaw R . AMPK: Mechanisms of Cellular Energy Sensing and Restoration of Metabolic Balance. Mol Cell. 2017; 66(6):789-800. PMC: 5553560. DOI: 10.1016/j.molcel.2017.05.032. View

4.
Illies C, Gromada J, Fiume R, Leibiger B, Yu J, Juhl K . Requirement of inositol pyrophosphates for full exocytotic capacity in pancreatic beta cells. Science. 2007; 318(5854):1299-302. DOI: 10.1126/science.1146824. View

5.
Krssak M, Falk Petersen K, Dresner A, Dipietro L, Vogel S, Rothman D . Intramyocellular lipid concentrations are correlated with insulin sensitivity in humans: a 1H NMR spectroscopy study. Diabetologia. 1999; 42(1):113-6. DOI: 10.1007/s001250051123. View