INS and Parkinson disease: Both diseases share several pathogenic mechanisms, including interactions between environmental risk factors and genetic susceptibility, the formation of toxic protein aggregates (such as islet amyloid polypeptide in type 2 diabetes and α-synuclein in PD), insulin resistance, mitochondrial dysfunction, and neuroinflammation (Tang et al., 2024; Zagare et al., 2024; Mukherjee et al., 2015).