AHR and diabetes mellitus: In addition, epigenetic and hormonal alteration are involved in the way that BPA and PCB deregulate development of peripheral IR, insulin production, pancreatic islet beta-cell function and mass, impairing insulin signaling, output and increasing cell apoptosis; by these means, those EDCs promote DM onset in insulin-resistant, obese individuals with type 2 DM; as an example, PCB activates the aryl hydrocarbon receptor (AHR) and inhibits the transcription of factor Nrf2a and PFOA inducing pre-proinsulin expression by increasing the proinsulin/insulin ratio.