According to a new report published in the journal eLife, microbiota present in the body, including bacteria, archaea, protists, fungi, and viruses, work with SARS-CoV-2 to further the severity of the infection in obese and diabetic people.
The analysis gave an insight into why the condition gets worsened for Covid-19 positive people with diabetes or obesity.
Author of the analysis Philipp Scherer, Professor at the Department of Internal Medicine, and Director of the Touchstone Diabetes Centre, at the University of Texas Southwestern Medical Centre, Dallas, US, said: “There is rapidly emerging evidence highlighting obesity and type 2 diabetes as key risk factors linked to the severity of Covid-19 infections in all ethnic groups.”
He added: “However, the detailed underlying connections with these risk factors remain largely unknown.”
Also read: Covid-19 persists longer in obese people: Report
In the analysis, Scherer and his team divided mechanisms into two cohorts: those connected with the ACE2 (Angiotensin-converting enzyme 2) receptor, and those providing interaction between Covid-19 and pre-existing bacterial conditions.
ACE2 resides on many human organs, including lungs and nostrils, among others. The coronavirus clings on to these receptors to proliferate.
Researchers speculated that increased amounts of ACE2 in obese and diabetic people makes it easier for the virus to enter and cause severity.
Alternatively, increased shedding of ACE2 in people with obesity causes it to move to the lungs, where the virus can use it, researchers stated.
Read also: Covid-19 persists longer in obese people: Report
Another factor that plays a pivotal role in the progression of lung diseases is our body’s microbiota, the authors of the study said.
The human body carries over 100 trillion bacteria — outnumbering the number of our own cells. Researchers noted that people with obesity most likely suffer from body-wide dissemination of bacteria and the substances they produce, which in turn causes low-level continuous inflammation in different tissues.
The team also noted how host bacteria may drive coronavirus severity. One potential culprit is the lipopolysaccharides (LPS) that bacteria produce, which have been shown to cooperate with other coronaviruses to induce SARS in pigs.
It is possible that these LPS molecules join forces with Covid-19 in humans and trigger a chain of events that causes healthy tissue to transform into scarred tissue — as Covid-19 does in the lungs, researchers added.
Scherer further explained: “While all of these potential mechanisms can contribute to the severity of Covid-19, we believe that one of them plays the predominant role and that this must be present not only in obese and diabetic patients but also in other groups of increased risk in Covid-19.”