Drugs Mimicking Cigarette Smoke May Help Covid Therapy: Study by Japanese Researchers
Researchers in Hiroshima have identified two drugs that mimic the effect of chemicals in cigarette smoke and reduce the ability of the SARS-CoV-2 virus, the virus that causes Covid-19, to enter the body. cells, leaving the possibility of smoking open for the time being.
The two drugs – 6-formylindolo (3,2-b) carbazole (FICZ) and omeprazole (OMP) mimic the effects of cigarette smoke to bind to a receptor in mammalian cells that inhibits the production of ACE2 proteins, a process that appears to reduce the ability of the SARS-CoV-2 virus.
Results appear in the journal Scientific reports. The ingredients – FICZ is a derivative of the amino acid tryptophan, while OMP is a drug already widely used in the treatment of acid reflux and peptic ulcers.
There is a kind of paradox when it comes to smoking and Covid-19. Active smoking is associated with increased severity of the disease, but at the same time, many reports have suggested a lower number of Covid cases in smokers than in non-smokers.
“We must point out the presence of strong evidence showing that smoking increases the severity of Covid-19,” said Keiji Tanimoto of the Institute for Research in Radiology and Medicine at Hiroshima University. âBut the mechanism we discovered here deserves further investigation as a potential tool to fight SARS-CoV-2 infections,â Tanimoto added.
Cigarette smoke is known to contain polycyclic aromatic hydrocarbons (PAHs). These can bind and activate aryl hydrocarbon (AHR) receptors.
How it works?
The researchers wanted to study the effect of drugs that activate AHR on the expression of genes that control the production of the ACE2 protein, the infamous receptor protein on the surface of many types of cells that functions as a lock that the virus does. SARS-CoV-2 is able to choose. After binding the virus to the ACE2 protein, it can then enter and infect the cell.
Scientists found that cells from the oral cavity, lungs and liver had the highest ACE2 expression. These cells with high ACE2 expression were then subjected to various doses of cigarette smoke extract for 24 hours.
Additionally, using RNA sequencing analysis, they found that cigarette smoke extract and these two drugs – which all act as AHR activators – are able to suppress the expression of ACE2 in mammalian cells and in doing so reduce the ability of the SARS-CoV-2 virus to enter the cell.
Based on the lab’s results, the team is currently conducting preclinical and clinical trials on the drugs as a new anti-Covid-19 treatment.