Preserving insulin levels within strict guidelines is a daily challenge for individuals with diabetes. Researchers have now discovered that managing blood insulin levels could also help reduce the risk of COVID-19.
The study has shown that a protein known as GRP78 helps the SARS-CoV-2 virus in binding to and entering cells. The SARS-CoV-2 virus is the virus that leads to COVID-19. GRP78 is a protein that’s located in adipose (fat) tissue. Obese, older, and diabetic individuals are all more susceptible to COVID-19 and, although reasons for this are still unclear, the researchers shed some light on this issue.
It has been proposed that adipose tissue could be a reservoir for SARS-CoV-2, so the researchers looked into whether there’s any association between excess adipose tissue in obese, older, and diabetic individuals and their susceptibility to COVID-19.
To achieve this, the research team examined GRP78, which has been proposed to be involved in SARS-CoV-2 and human cell interaction. The main way SARS-CoV-2 gains entry into human cells is via a spike protein on the surface of the virus that binds to a human cell protein known as angiotensin-converting enzyme 2 (ACE2). It was found that the spike protein is also able to bind to GRP78 directly and that the existence of GRP78 increases the ACE2 binding. To get a proper picture of the involvement of GRP78 in COVID-19 susceptibility the researchers looked at how much GRP78 protein is found in tissues from obese, older, and diabetic individuals.
It’s already known that obesity, aging, and diabetes are linked to increased blood insulin levels. So the researchers considered if insulin was involved in expression of GRP78. They discovered that exposure of cells to insulin did induce GRP78 expression. The study found that treatment making use of commonly prescribed insulin level reducing anti-diabetic drugs successfully reduced expression level of GRP78. More importantly, they demonstrated in a mouse model that calorie restriction and exercise proved helpful in reducing GRP78 levels in adipose tissue.
The study results indicate that a high level of blood insulin is an important risk factor that can predispose obese, older, and diabetic people to COVID-19 infection. Therefore, managing blood insulin with exercise, diet, or pharmacological interventions could help reduce the risk for these individuals. Granted the impact of the COVID-19 pandemic globally, these study results offer important insights into how to help reduce the risk of infection in these susceptible individuals.
