Inceptor (encoded by Iir) is a novel receptor that inhibits insulin receptor and insulin-like growth factor signalling. A previous study showed that loss of inceptor from β-cells in lean normoglycaemic mice improved glucose homeostasis. Now, the same group reports findings on inceptor loss in mouse models of obesity.

Inceptor is widely expressed in neurons and pan-neuronal Iir deletion in male DIO mice also improved glucose tolerance compared with wild-type control mice. Interestingly, however, these same effects were not seen with targeted deletion of Iir from AgRP neurons and POMC neurons (which are key for glucose control). Thus, the mechanisms causing improvements in mice with neuronal inceptor loss are still unclear. Finally, targeted adult-onset deletion of Iir from β-cells in DIO male mice also improves β-cell function and glucose control, corroborating findings from the previous study.