**4. Amyloidosis' association with diabetes mellitus**

Case studies have shown a deep connection in patients who suffer from amyloidosis and type 2 diabetes, especially in those with pancreatic damage [9, 10]. Studies have focused on a neuro pancreatic hormone called islet amyloid polypeptide (IAPP) or amylin, secreted along with insulin by β pancreatic cells, and its possible etiology in type 2 diabetes [11]. IAPP functions as a glucose homeostatic regulator, but once it suffers synthetic alterations, it starts to accumulate inside and outside the pancreatic cells resulting in apoptosis [12]. Although the specific etiology has remained unknown, there have been many hypotheses on what causes these pancreatic amyloid deposits. One of the most accepted hypotheses consists of a malfunctioning β pancreatic cell which is unable to correctly process amylin, resulting in the installment of amyloid proteins inside and outside the cells [13]. Another accepted theory indicates the genetic overexpression of amylin, which causes amyloid deposits, although there has not been a proven correlation (in humans) between high IAPP circulating levels and glucose intolerance [14]. It has been proved that the amino acids within the 26–29 sequence are a determinant factor proved in the development of amyloid deposits only in humans, simians, and felines, which are presumed to be the only three species to suffer from an amyloid deposit diabetes [9, 10, 15, 16]. It has been proved that in 9% of the diabetic population, there has been an identified mutation within the promoter region in the amyloid gene, increasing its transcription [17–19]. For years it has been proven that high blood glucose is not only toxic to β pancreatic cells, but it also generates an overexpression on the IAPP gene which contributes to pancreatic amyloid deposits, inducting cellular apoptosis [12]. It was never clear whether IAPP was the cause or the consequence of diabetes, but once the genetic mutation in the promoter region was finally identified, there is still more research to be done in order to be completely certain.
