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bioRxiv · 10.1101/2025.03.26.645414

α-Melanocyte Stimulating Hormone Reduces Blood Glucose Across Species

Abstract

Peripheral administration of -melanocyte stimulating hormone (-MSH) promotes glucose uptake in skeletal muscle via a melanocortin 5 receptor (MC5R)-dependent mechanism in rodents. Here we demonstrate that this pathway is functional in humans. During an oral glucose tolerance test (GTT) in healthy human volunteers, peripheral administration of -MSH was well tolerated, and reduced glucose and insulin incremental area under the curve by 39% and 35%, respectively. During a GTT in non-human primates, both -MSH and a selective MC5R agonist, PG-901, increased glucose tolerance. In vitro, both -MSH and PG-901 induced glucose uptake in primary human and non-human primate myotubes and immortalised human myotubes. Subcutaneous injection of PG-901 reduced blood glucose concentrations during a GTT in WT mice but had no effect in MC5R deficient mice. Thus, the novel MC5R-skeletal muscle pathway found in animals is functional in humans and represents a novel target for glycaemic control in people with diabetes.

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BibTeXRIS

Swan, P., Johnson, B., Simonds, S. E., Mustafa, T., Houghton, M. J., Samarasinghe, S., Docherty, N. G., Luli, M., Pryor, J. T., Greenough, C., Gibbon, A., Thompson, P. E., Yue, W. K., de Vito, G., Williamson, G., le Roux, C. W., Miras, A. D., Cowley, M. A.. 2025-03-29. α-Melanocyte Stimulating Hormone Reduces Blood Glucose Across Species. https://doi.org/10.1101/2025.03.26.645414

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