Steroid-like compounds in Taiwanese endemic fungi (known as antcin) are said to be able to inhibit host cell receptors for severe acute respiratory syndrome caused by SARS-CoV-2. This type of fungus can prevent viral infections and COVID-19 from developing.
Although worldwide distribution of the vaccine aims to stop the ongoing COVID-19 pandemic, the high number of cases and deaths due to the lack of effective drugs to help prevent or slow down SARS-CoV-2 infection. So, the double effects of vaccines and drugs are something we need to address this pandemic.
Therefore, the search for the best drug candidate for COVID-19 continues. One of the main targets of the anti-COVID-19 compound is the angiotensin converting enzyme 2 (ACE2), which is actually a host cell surface receptor utilized by SARS-CoV-2 to initiate the entire infection process.
Medicinal plants play an important role in the prevention and treatment of certain diseases, and some phytochemical compounds have been shown to have ACE2 inhibitory activity. For that reason as well, these compounds were investigated in depth using different preclinical and clinical computational models.
Cited from Medical News, Antrodia cinnamomea and Antrodia salmonea are two endemic fungi found in Taiwan with much pharmacological activity. Its potential use against the SARS-CoV-2 virus that causes COVID-19 was recently explored by a group of researchers from the National Chung Hsing University in Taiwan.
In summary, these authors have explored the inhibitory effects of various antcin on ACE2 receptors. Antcin is a steroid-like compound produced by the endemic fungi mentioned above, and this study aimed to assess the properties of 99% pure antcin-A, antcin-B, antcin-C, antcin-H, antcin-I and antcin-M.
In this study, researchers found that all antcin -treated - with the exception of antcin -M - showed significant inhibition of ACE2 activity. More specifically, there was a strong reduction in human ACE2 levels in HT-29 cells when antcin-A, antcin-B, antcin-C and antcin-I were used, and a moderate reduction was seen in cells treated with antcin-H.
In addition, all antcin tested failed to inhibit the expression of messenger RNA (mRNA) either ACE2 or TMPRSS2 (the latter being an endothelial cell surface protein involved in viral entry and spread of Corona virus) in HT-29 cells, implying that ACE2-reducing antcin induced is not the result of down-regulation at the mRNA level.
This type of reduction in the expression of ACE2 and TMPRSS2 proteins in host cells may indeed represent a viable strategy for the prophylaxis and treatment of SARS-CoV-2 infection, as it can successfully halt one of the most important events in human-to-human transmission.
The researchers note, all of these findings should be viewed strictly as a preliminary step so that for now, it is not possible to claim antcin as a COVID-19 drug. However, the results appear promising and this steroid-like compound may be an important addition in our fight against COVID-19 in the future.