South Korean scientists have found that the local plants contain chemical compounds that are highly effective in preventing the entry of coronaviruses mutated by the Corona virus, including Omicron, into human cells.
A team of researchers led by the director of the Institute of Life Sciences at the Institute of Basic Sciences (IBS) in South Korea, Dr. C. Justin Lee conducted the study, which was published in the journal “Search for viruses” (Antivirus Research) and transferred from the site “Your Notice” (Self warned).
According to the study, the effective compounds of the “saponin” category were found in two South Korean plants, “Codonopsis lanceolata”, which is used as a medicinal herb in South Korea and is widely cultivated there, and has many uses throughout the world history of korean cuisine.
The other plant, Aster koraiensis, also known as “Korean star”, is a common daisy-like flower found only on the Korean peninsula.
Researchers have found that these compounds are particularly effective at inhibiting SARS-CoV-2 infection by blocking the membrane fusion that allows viruses to invade host cells.
Coronaviruses enter human cells via endosomes or fusion in plasma membranes, in both cases a process known as “membrane fusion” must occur between the coronavirus envelope and the cell membrane.
In this study, the research team revealed that two saponin compounds, “Astersaponin I” and “Lansemaside A” in the two plants mentioned above, are able to prevent the membrane fusion between the coronavirus and human cells, and thus block effectively all the ways the virus can infect host cells.
The research team first created a SARS-CoV-2 infection model using human lung cells that produce the ACE2 receptor protein and a pseudovirus that expresses a spike protein on the surface of the coronavirus, and then the cells were treated with Astersaponin 1 .″ and “Lansmaside A ” to test the inhibitory effect of these compounds on viral infection.
Astersaponin 1 and Lansmaside A
Astersaponin 1 and Lansmaside A are two compounds of the class of triterpenoid saponins, both with central hydrocarbon structures very similar to those of cholesterol, which is the main component of cell membranes, and furthermore, these compounds contain a chain of polysaccharides attached to one side of the hydrocarbon structure.
The central portion of saponins easily binds to the cell membrane due to its similarity to cholesterol. When the molecule penetrates the cell membrane, the long sugar chain protrudes from the membrane. This protruding sugar is thought to be what prevents the cell membrane from fusing with coronavirus envelope.
SARS-CoV-2 mutants such as Omicron are more infectious than the original virus due to mutations in the spike protein, which increase their affinity for the ACE2 cell receptor. In order to increase the virus’ ability to attract host receptors cell, these viruses will not be able to enter the cell if the entire process of membrane fusion, which occurs after viral binding to the receptor, is prevented.
Other effective saponins
On the other hand, the “IPS” team members previously worked with Dr. Kim Seongtaek of the Korean Pasteur Institute and discovered another natural triterpenoid saponin called “platycotin D” from balloon flower, and found that this saponin it is also effective against SARS -CoV-2″, and this research was published in the journal “Experimental & Molecular Medicine” in May 2021.
The IPS researchers, in collaboration with Professor Han Sunkyu’s team from the Korea Advanced Institute of Science and Technology (KAIST), have discovered a way to synthesize synthetic saponins that potentially have more potent effects than natural saponins.
The team produced dozens of compounds from synthetic saponins that have polysaccharide chains of different lengths and types, and tested them and found that one of these saponins had twice the activity of ‘Platikotin D’. This research was published in the Journal of Bioorganic Chemistry.
COVID-19
“Covid-19” is an infectious disease caused by the “SARS-Cove-2” virus, and the disease has spread to the world in 2020, which led the World Health Organization to declare a public health emergency after classifying its outbreak as a pandemic in March 2020.
The disease causes respiratory symptoms ranging from mild to moderate in severity in most infected people, as most of them recover without the need for special treatment or medical attention, but there are some who develop severe symptoms and require medical attention , and they are mostly elderly patients and those suffering from chronic conditions such as diabetes, cardiovascular disease, chronic respiratory disease, cancer, etc. However, it is possible for any person to be exposed to severe symptoms due to “Covid-19” infection, which can cause death, regardless of the person’s age and state of health at the time of infection.
Current treatment for COVID-19
According to the Centers for Disease Control and Prevention (CDC), vaccinations have helped reduce the spread of the disease, and mild to moderate symptoms can be controlled with over-the-counter medications such as pain relievers and fever reducers.
In some cases, certain antiviral drugs that stop the virus from multiplying and monoclonal antibodies that help the immune system recognize and respond to the virus more effectively may be used.
