COVID-19 Herbs: American In Vitro Study Shows That Herb Extract Of Artemisia Annua Inhibits SARS-CoV-2 Replication
: Scientists from Columbia University in New York, the University of Washington, and Worcester Polytechnic Institute have demonstrated in a new vitro study that extracts from the herb Artemisia Annua inhibits the SARS-CoV-2 coronavirus replication, making it a possible therapeutic candidate for COVID-19.
Artemisia Annua Being Grown In Dok Kham Thai-Phayao, Thailand.
The current COVID-19 pandemic has so far claimed more than 1.94 million lives and infected more than 91 million people globally with figures still rising exponentially.
To date there are no known drugs or antivirals that can treat COVID-19 aside from scams perpetrated in America by the Trump administration and its regulatory agency the US FDA and various agencies including the NIH involving the hydroxychloroquine, remdesivir, convalescent plasma and monoclonal antibodies sagas. The effectiveness of the current COVID-19 vaccines also initiated by the Trump administration are now also questionable.
Despite initially laughing off at Asian countries and South American countries study and usage of herbs and traditional medicine to treat COVID-19 , these same Westerners are now reverting back to these very same herbs.
In this study, the research team shows that extracts of the medicinal plant, Artemisia annua
L., which produces the antimalarial drug artemisinin, prevents SARS-CoV-2 replication in vitro.
The study team measured antiviral activity of dried leaf extracts of seven cultivars of A. annua
sourced from four continents. Hot-water leaf extracts based on artemisinin, total flavonoids, or dry leaf mass showed antiviral activity with IC50 values of 0.1-8.7 μM, 0.01-0.14 μg, and 23.4-57.4 μg, respectively. One sample was >12 years old, but still active. While all hot water extracts were effective, concentrations of artemisinin and total flavonoids varied by nearly 100-fold in the extracts and antiviral efficacy was inversely correlated to artemisinin and total flavonoid contents.
Artemisinin alone showed an estimated IC50 of about 70 μM, and antimalarial artemisinin derivatives artesunate, artemether, and dihydroartemisinin were ineffective or cytotoxic at elevated micromolar concentrations. In contrast, the antimalarial drug amodiaquine had an IC50 = 5.8 μM. The extracts had minimal effects on infection of Vero E6 or Calu-3 cells by a reporter virus pseudotyped by the SARS-CoV-2 spike protein. There was no cytotoxicity within an order of magnitude of the antiviral IC90 values.
The study findings suggest the active component in the extracts is likely something besides artemisinin or is a combination of components acting synergistically to block post-entry viral infection. Further studies will determine in vivo efficacy to assess whether A. annua
might provide a cost-effective therapeutic to treat SARS-CoV-2 infections.
The study findings were published on a preprint server and are currently being peer reviewed. https://www.bio
Thailand Medical News had already brought up the attention of Artemisia Annua as a potential herb to treat COVID-19 since May 2020.
We had also initiated our own research and have incorporated artemisia annua in our own therapeutic teas. https://www.thailandmedical.news/news/new-therapeutic-teas-
We however have to warn that usage of the herb Artemisia annua or any of its extracted phytochemicals alone will however not make it effective to treat COVID-19 disease as in vivo and in actual human bodies, the process of targeting and effectively eradicating the SARS-CoV-2 coronavirus is actually much more complicated and other phytochemicals are also needed from other herbs to create an effective therapeutic and antiviral candidate.
The herb also known as “Sweet wormwood,” Artemisia annua
) is an herb from Asia and Africa that produces the antimalarial agent artemisinin.
The study team in this research have demonstrated that hot-water leaf A. annua extracts based on artemisinin, total flavonoids, or dry leaf mass show antiviral activity against SARS-CoV-2.
Corresponding author Dr Pamela Weathers from the Department of Biology and Biotechnology, Worcester Polytechnic Institute- Massachusetts told Thailand Medical News, “This is the first report of anti-SARS-CoV-2 efficacy of hot water extracts of a wide variety of cultivars of A. annua sourced from four continents. Further studies will determine in vivo efficacy to assess whether A. annua might provide a cost-effective therapeutic to treat SARS-CoV-2 infections.”
The herbal plant A. annua and the artemisinin it produces have been safely used to treat a range of ailments, particularly malaria, for more than 2,000 years.
Importantly one study conducted in 2005 also demonstrated that the herb has an antiviral effect against SARS-CoV-1 – the agent responsible for the 2002 to 2003 SARS outbreak. https://pubmed.ncbi.nlm.nih.gov/15885816/
Also interesting is the fact that both the A. annua plant and artemisinin have been shown to reduce levels of the inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in vivo. https://pubmed.ncbi.nlm.nih.gov/28864166/
Dr Weathers added, “These effector molecules can be problematic during the ‘cytokine storm’ suffered by many SARS-CoV-2 patients.”
The study team hypothesized that encapsulated powdered dried leaves of A. annua might represent a safe and cost-effective approach to treating SARS-CoV- 2 infections.
The team tested the effects of extracts from seven A. annua cultivars sourced from four different continents on SARS-CoV-2 propagated in Vero E6 cells. They also assessed correlations of antiviral efficacy with artemisinin, total flavonoid contents, and dry leaf mass.
It was found that all extracts demonstrated anti-SARS-CoV-2 activity. The IC50 values (concentration of drug that inhibits 50% of target) calculated based on artemisinin, total flavonoid content or dry leaf mass ranged from 0.1 to 8.7µM, 0.01 to 0.14µg and 23.4-57.4µg, respectively.
Interestingly one sample that was obtained in 2008 still exhibited anti-SARS-CoV-2 activity that was comparable to the most recently harvested cultivar samples.
Significantly this suggests that the active principle is ubiquitous to different A. annua cultivars and is chemically stable during long-term room temperature dry storage, say the researchers.
The antiviral efficacy was inversely correlated with artemisinin and total flavonoid contents
Though the hot water extracts were effective, antiviral efficacy was inversely correlated with artemisinin and total flavonoid contents.
Detailed analysis of artemisinin alone had an estimated IC50 of around 70µM, and while the artemisinin derivative artemether showed efficacy at 1.23µM, it was cytotoxic at concentrations any higher than this.
Also the derivatives artesunate and dihydroartemisinin were also ineffective at levels of less than 100µM.
However by contrast, the antimalarial drug amodiaquine had an IC50 of 5.8 µM.
Also it should be noted that Spearman’s Rho analysis showed that neither IC50 nor IC90 values of the hot-water extracts correlated with artemisinin or total flavonoid content.
The study team also found that the extracts had minimal antiviral effects against pseudoviruses containing the SARS-CoV-2 spike protein ie the main structure the virus uses to bind to and enter host cells. The team says this suggests that A. annua inhibits SARS-CoV 2 infection primarily by targeting a post-entry step.
De Weathers added, “The results suggest the active component in the extracts is likely something besides artemisinin or is a combination of components acting synergistically to block post-entry viral infection.”
In order to investigate dried leaf A. annua (DLA) as a potential therapeutic, Dr Weathers consumed 3 grams of encapsulated DLA of the SAM cultivar, and the team tracked artemisinin as a marker molecule by drawing blood samples two and five hours later.
It was found that at two and five hours following ingestion, the artemisinin levels were 7.04µg and 0.16 µg per mL serum, respectively. At 2 hours, this corresponded to 2.35µg artemisinin/mL serum of DLA-delivered artemisinin per gram of DLA consumed.
The study team says that while human trials are clearly needed, the study suggests that consuming reasonable amounts of DLA may serve as a cost-effective treatment for SARS-CoV-2 infection.
De Weathers concluded, “If subsequent clinical trials are successful, A. annua could potentially serve as a safe therapeutic that could be provided globally at a reasonable cost and offer an alternative to vaccines.”
The study team also noted that the broad scale use of both artemisinin and non-artemisinin compound antimalarials including A. annua tea infusions across Africa may help in part explain why despite having anti-SARS-CoV-2 antibodies, Africans have not to date suffered the clinical scourge of SARS-CoV-2 like the rest of world . https://facultyopinions.com/prime/739014636
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