How the Covid virus uses the body’s fat cells to replicate

SARS-CoV-2, the virus that causes Covid-19, undertakes a massive takeover of the body’s fat processing system, creating cellular stores of fat that allow the virus to hijack the body’s molecular machinery and cause disease, study suggests.

After scientists discovered the important role of fat for SARS-CoV-2, they used weight-loss drugs and other fat-targeting compounds to try to stop the virus in cell culture. Cut off from its fatty fuel, the virus stopped replicating within 48 hours, the team from Oregon Health & Science University (OHSU) and the US Department of Energy (DoE) revealed.

However, in the paper published in the journal Nature Communications, the team cautioned that the results are in cell culture, not humans, and that there is still a lot of research to see if such compounds show promise for people diagnosed with Covid.

“When the virus replicates, it needs a continuous supply of energy,” said Fikadu Tafesse, assistant professor of molecular microbiology and immunology at OHSU.

“More triglycerides could provide that energy in the form of fatty acids. But we don’t know exactly how the virus uses these lipids to its advantage,” Tafesse added.

In the study, the team investigated the effect of SARS-CoV-2 on more than 400 lipids in two different human cell lines.

Scientists found a massive change in lipid levels, with some fats increasing up to 64 times. In one cell line, almost 80% of the fats were altered by the virus; in the other, slightly more than half levels have been changed.

The most affected lipids were triglycerides, those little packets of fat that most patients try to keep to a minimum. Triglycerides are crucial to our health, allowing us to store energy and maintain healthy membranes in our cells.

It turns out that those oily fat drops are also essential for the Covid virus.

The team discovered that SARS-CoV2 does not simply increase the number of triglycerides in our cells. The virus also alters much of our fat processing system, altering the body’s ability to use fat for fuel.

At the same time, an approved weight-loss drug, Orlistat, a lipase inhibitor, and an experimental compound known as GSK2194069 stopped the virus. These and other compounds worked against all SARS-CoV2 variants tested: Alpha, Beta, Gamma, and Delta.