Arsenic exposure accelerates type 1 diabetes mellitus progression via pyroptosis pathway in mice

The relationship between arsenic exposure and the development of diabetes mellitus has garnered significant interest in recent years. However, current experimental studies have not definitively established the role of arsenic in the onset of diabetes mellitus. To investigate this relationship specifically concerning type 1 diabetes mellitus, Streptozocin (STZ) was utilized as an inducer to initiate the fundamental pathological changes associated with the disease. A high dose of STZ (50 mg/kg) served as the positive control, while a low dose of STZ (20 mg/kg) was administered in combination with arsenic at varying doses. The objective was to determine whether arsenic enhances the effects of STZ, thereby leading to an expedited onset and progression of type 1 diabetes mellitus. The preliminary investigation into the impact of arsenic exposure on experimental type 1 diabetic mice focused on the NLRP3/Caspase-1/GSDMD mediated pyroptosis pathway. The results showed that fasting blood glucose (FBG) was increased, glucose tolerance was impaired, insulin sensitivity was decreased, fasting serum insulin and the homeostatic model assessment-β (HOMA-β) were significantly reduced, hair arsenic content was increased, reactive oxygen species(ROS), interleukin (IL)-1β and IL-18 contents were increased, and the pathological morphology of pancreas was more serious in the combined group. Moreover, the expression levels of proteins associated with the NLRP3/Caspase-1/GSDMD-mediated pyroptosis pathway were elevated in the combined group. This study illustrates that exposure to arsenic, combined with low-dose STZ, not only leads to pancreatic injury in mice, impacting insulin secretion and causing elevated blood glucose levels, thereby hastening the progression of type 1 diabetes, but also induces pyroptosis in pancreatic tissues by influencing the NLRP3/Caspase-1/GSDMD signaling pathway, further facilitating the development of type 1 diabetes.