Stress unmasks impaired endocrine coordination of glucose metabolism in dystrophin deficiency

Abstract

Skeletal muscle orchestrates systemic metabolism, dynamically coordinating glucose uptake and fuel use to match energy demand. In Duchenne muscular dystrophy, loss of dystrophin is associated with altered metabolic regulation. In the mdx mouse, we show that physiological stress reveals impaired coordination between insulin and stress responses: glucocorticoid signalling increases without a proportional rise in insulin secretion, resulting in systemic hyperglycaemia despite preserved capacity for muscle glucose uptake. These data support a multi-tissue dystrophinopathy associated with altered endocrine-metabolic coordination. Skeletal muscle glycogen is elevated and incompletely mobilised under stress. The heart maintains high glucose uptake, whereas the brain exhibits reduced uptake, highlighting tissue specific differences in metabolic response. Acute insulin supplementation improves systemic glucose control and restores stress-induced behavioural deficits. Likewise, empagliflozin-mediated glucose offloading reduces stress-associated blood glucose spikes and is associated with improved muscle function to levels comparable with standard care prednisolone. These findings identify impaired coordination of endocrine and metabolic responses during stress as a contributor to metabolic vulnerability in DMD and suggest that modulating insulin availability or glucose flux can improve systemic metabolic control.