Unraveling the relationship among insulin resistance, IGF-1, and amyloid-beta 1–40: Is the definition of type 3 diabetes applicable in the cardiovascular field?

The concept of “type 3 diabetes” has emerged to define alterations in glucose metabolism that predispose individuals to the development of Alzheimer's disease (AD). Novel evidence suggests that changes in the insulin/insulin-like growth factor 1 (IGF-1)/growth hormone (GH) axis, which are characteristic of Diabetes Mellitus, are one of the major factors contributing to excessive amyloid-beta (Aβ) production and neurodegenerative processes in AD. Moreover, molecular findings suggest that insulin resistance and dysregulated IGF-1 signaling promote atherosclerosis via endothelial dysfunction and a pro-inflammatory state. As the pathophysiological role of Aβ1–40 in patients with cardiovascular disease has attracted attention due to its involvement in plaque formation and destabilization, it is of great interest to explore whether a paradigm similar to that in AD exists in the cardiovascular field. Therefore, this review aims to elucidate the intricate interplay between insulin resistance, IGF-1, and Aβ1–40 in the cardiovascular system and assess the applicability of the type 3 diabetes concept. Understanding these relationships may offer novel therapeutic targets and diagnostic strategies to mitigate cardiovascular risk in patients with insulin resistance and dysregulated IGF-1 signaling.