NF-κB-inducing kinase (NIK) is activated in pancreatic β-cells but does not contribute to the development of diabetes

The transcription factor nuclear factor-kappa B (NF-kappa B) has a key role in the pathogenesis of diabetes and its complications. Although activation of the canonical NF-kappa B pathway in beta-cells is generally deleterious, little is known about the role of the non-canonical NF-kappa B signalling and its main regulator, the NF-kappa B-inducing kinase (NIK), on pancreatic beta-cell survival and function. Previous studies based on models of NIK overexpression in pancreatic islet cells showed that NIK induced either spontaneous beta-cell death due to islet inflammation or glucose intolerance during diet-induced obesity (DIO) in mice. Therefore, NIK has been proposed as a potential target for diabetes therapy. However, no clear studies showed whether inhibition of NIK improves diabetes development. Here we show that genetic silencing of NIK in pancreatic beta-cells neither modifies diabetes incidence nor inflammatory responses in a mouse model of immune-mediated diabetes. Moreover, NIK silencing in DIO mice did not influence body weight gain, nor glucose metabolism. In vitro studies corroborated the in vivo findings in terms of beta-cell survival, function, and downstream gene regulation. Taken together, our data suggest that NIK activation is dispensable for the development of diabetes.