Hope for preventing future pandemics is provided by an analysis of the life cycle of RNA viruses, their genetics, and the compounds that could disrupt them.
The genomic and life history characteristics of three types of viruses that have triggered endemic and global pandemics in the past have been broken down by researchers at the Scripps Institution of Oceanography and the Skaggs School of Pharmacy and Pharmaceutical Sciences at the University of California San Diego, and natural products have been identified.
Marine chemists Mitchell Christy, Yoshinori Uekusa and William Gerwick and immunologist Lena Gerwick identify the basic biology of three families of RNA viruses and how they infect human cells in a review paper appearing in the Journal of Natural Products.
Instead of DNA, these viruses use RNA to store their genetic material, a property that makes them rapidly evolve.
The team then explains the natural products shown to be able to suppress them and outlines alternative methods for treatment.
The lead author, Christy, says, “We wanted to evaluate the viruses responsible for these deadly outbreaks and identify their vulnerabilities,” We look at their commonalities and identify possible methods for combating and spreading their replication.
Natural products are found to be a valuable source of inhibitors that can serve as the basis for new drugs to be created that target these viruses.
The research team is from the Center for Marine Biotechnology and Biomedicine (CMBB) of Scripps Oceanography, which collects chemical compounds found in the marine environment and analyzes them as antibiotics, anticancer drugs and other medicinal products for their possible effectiveness.
In early 2020, a medicine known as marizomib entered final clinical trials as a possible cure for brain tumors.
The medication comes from a genus of marine bacteria originally obtained from seafloor sediments in 1990 by CMBB researchers.
An description of the structure of viruses in the Coronaviridae, Flaviviridae and Filoviridae families is provided by the researchers, sponsored by the National Institutes of Health and the UC San Diego Chancellor’s Office.
Viruses that have contributed to COVID-19, dengue fever, West Nile encephalitis, Zika, Ebola and outbreaks of Marburg disease are among these groups.
The group then recognizes compounds that have been shown to work against these viruses produced by marine and terrestrial organisms.
It is suspected that these compounds have a molecular architecture that makes them potential candidates for use as viral inhibitors that prevent the entry or replication of viruses into healthy human cells.
The aim of the report, the researchers said, was to enhance the process of drug production as new pandemics occur such that, in the face of new challenges, control of disease transmission can be accelerated.
“It is simply common sense that we should create the necessary infrastructure to develop treatments more quickly when future pandemics occur,” the study concluded. “One such recommendation is to create and maintain international compound libraries of compounds that have antiviral, antibacterial or antiparasitic activity.”
To achieve this goal, the researchers said, it would be important to reach international agreements to resolve issues of intellectual property, the rights and obligations of researchers, and other complex issues.
And while the production of vaccines against SARS-CoV-2 infection has made tremendous progress, successful antiviral drugs are still urgently required to treat COVID-19 infection in unvaccinated individuals or in cases where the efficacy of a vaccine decreases over time, the researchers said.
Although multiple antiviral molecules, such as remdesivir, lopinavir-ritonavir, hydroxychloroquine, and type I interferon therapy, have been tested for use in the clinic, they have all demonstrated minimal to no efficacy in large-scale trials.
Effective antiviral medicines have yet to be identified and developed.
“Natural Products with Potential to Treat RNA Virus Pathogens Including SARS-CoV-2” by Mitchell P. Reference:
Journal of Natural Products, Christy, Yoshinori Uekusa, Lena Gerwick and William H. Gerwick, Dec. 22, 2020. DOI: 10.1021/acs.jnatprod.0c00968prod.0c00968
Funding: Public Health Institutes