Matriptase-2 deficiency protects from obesity by modulating iron homeostasis

Alterations in iron status have frequently been associated with obesity and other metabolic disorders. The hormone hepcidin stands out as a key regulator in the maintenance of iron homeostasis by controlling the main iron exporter, ferroportin. Here we demonstrate that the deficiency in the hepcidin repressor matriptase-2 (Tmprss6) protects from high-fat diet-induced obesity. Tmprss6 ^-/- mice show a significant decrease in body fat, improved glucose tolerance and insulin sensitivity, and are protected against hepatic steatosis. Moreover, these mice exhibit a significant increase in fat lipolysis, consistent with their dramatic reduction in adiposity. Rescue experiments that block hepcidin up-regulation and restore iron levels in Tmprss6^-/- mice via anti-hemojuvelin (HJV) therapy, revert the obesity-resistant phenotype of Tmprss6^-/- mice. Overall, this study describes a role for matritpase-2 and hepcidin in obesity and highlights the relevance of iron regulation in the control of adipose tissue function.