Published online Oct 6, 2021. doi: 10.12998/wjcc.v9.i28.8327
Peer-review started: March 6, 2021
First decision: March 30, 2021
Revised: April 12, 2021
Accepted: July 29, 2021
Article in press: July 29, 2021
Published online: October 6, 2021
Processing time: 205 Days and 16.5 Hours
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have posed a problematic healthcare situation worldwide since December 2019. Diabetes mellitus is associated with an increased risk and severity of coronavirus disease 2019 (COVID-19). While interacting with various other risk factors, high blood sugar was found to reduce immunity and increase the replication of SARS-CoV-2. Oxidative stress and the release of pro-inflammatory cytokines are greater in diabetic individuals than in healthy people, worsening the outcome of SARS-CoV-2 infection in diabetics. Increased expression of furin and angiotensin converting enzyme 2 (ACE-2) receptor in the hyperglycemic environment may promote the entry of SARS-CoV-2 in the host cell. COVID-19 infection primarily modulates immune and inflammatory responses, and may cause a cytokine storm, resulting in possible lethal outcomes in diabetics. An experimental report suggests that ACE expressed in the pancreas and the SARS-CoV-2 virus invariably destroy β-cells which contain ACE-2 receptors and results in acute diabetes. Moreover, COVID-19 also causes hyperglycemia in an individual with diabetes which may be related to insulin resistance and destruction of β-cells during SARS-CoV-2 infection. Early observations also suggest a correlation between oral hypoglycemic agents and the risk of COVID-19. This review focused on the possible cause and mechanism involved in SARS-CoV-2 infection in diabetics and the role of antidiabetic drugs in COVID-19.
Core Tip: This review highlights the significant correlation between diabetes mellitus and coronavirus disease 2019 (COVID-19) in light of available published information. COVID-19 is responsible for increased risk and disease severity in diabetic patients. Cytokine storm, destruction of beta cells and the expression of angiotensin converting enzyme 2 are some of the fundamental mechanisms discussed. This review also summarizes the range of investigations that have been undertaken across a large set of published papers on COVID-19 and diabetes mellitus.