Could a family history of type 2 diabetes be a risk factor to the endothelial damage in the patient with COVID-19?

In December 2019, in China, a disease derived from a new beta coronavirus (SARS-CoV-2) was reported, which was termed coronavirus disease 2019 (COVID-19). Currently, it is known that endothelial cell dysfunction is a critical event in the infection by this virus. However, in a representative percentage of patients with COVID-19, neither cardiovascular disease nor diabetes mellitus, which could be linked with endothelial dysfunction, has been reported. Previous evidence has shown the presence of early endothelial dysfunction in healthy subjects but with a family history of type 2 diabetes (FH-DM2), where glucose metabolism, the synthesis of nitric oxide (NO), reactive oxygen species (ROS), as well as expression of genes involved with their synthesis are impaired. Besides, in subjects with an FH-DM2, the presence of hyperinsulinemia and high glucose levels are common events that could favor the infection of endothelial cells by the coronavirus. Interestingly, both events have been reported in patients with COVID-19, in whom hyperinsulinemia increases the surface expression of ACE2 through a diminution of ADAMTS17 activity; whereas hyperglycemia induces higher expression of ACE2 in different tissues, including microvascular endothelial cells from the pancreatic islets, favoring chronic hyperglycemia and affecting the release of insulin. Therefore, we hypothesized that an FH-DM2 should be considered an important risk factor, since the individuals with this background develop an early endothelial dysfunction, which would increase the susceptibility and severity of infection and damage to the endothelium, in the patient infected with the SARS-CoV-2.