摘要：Chronic Mg2 deficiency is the underlying cause of a broad range of health dysfunctions. As 25% of body Mg2 is located in the skeletal muscle, Mg2 transport and homeostasis systems (MgTHs) in the muscle are critical for whole-body Mg2 homeostasis. In the present study, we assessed whether Mg2 deficiency alters muscle fiber characteristics and major pathways regulating muscle physiology. C57BL/6J mice received either a control, mildly, or severely Mg2 -deficient diet (0.1%; 0.01%; and 0.003% Mg2 wt/wt, respectively) for 14 days. Mg2 deficiency slightly decreased body weight gain and muscle Mg2 concentrations but was not associated with detectable variations in gastrocnemius muscle weight, fiber morphometry, and capillarization. Nonetheless, muscles exhibited decreased expression of several MgTHs (MagT1, CNNM2, CNNM4, and TRPM6). Moreover, TaqMan low-density array (TLDA) analyses further revealed that, before the emergence of major muscle dysfunctions, even a mild Mg2 deficiency was sufficient to alter the expression of genes critical for muscle physiology, including energy metabolism, muscle regeneration, proteostasis, mitochondrial dynamics, and excitation–contraction coupling.
