COVID-19 Herbs: Saudi Arabia Study Demonstrates Possible Use Of Echinacea and St. John's Wort As Therapeutic Agents Against COVID-19
: Scientists from King Fahd Medical Research Center at King Abdulaziz University in a new study have demonstrated the antiviral effects of two medicinal herbs: Hypericum perforatum
also called St. John's Wort and Echinacea
or Purple Cone Flower against the SARS-CoV-2 coronavirus, the pathogen that causes COVID-19.the study showed that each herb as well as the two combined, exerted inhibitory and virucidal effects on SARS-CoV-2-infected Vero E6 cells.
Importantly the effects were most potent when cells were treated with H. perforatum
. A combination of the two herbs was the second most effective, and treatment with Echinacea alone was the least effective.
In this study and based on the previous reviews, Hypericum perforatum
(St. John’s Wort) and Echinacea
were tested in vitro
using Vero E6 cells for their anti-viral effects against the newly identified SARS-CoV-2 through its infectious cycle from 0 to 48 hours post infection. The hypericin (0.9 mg) of H. perforatum
and the different parts (roots, seeds, aerial) of two types of Echinacea
species (Echinacea purpurea
and Echinacea angustifolia
) were examined for their efficacy in certain concentration and under light-dependent anti-viral activities to measure the inhibition of the SARS-CoV-2 mRNA expression of RNA-dependent RNA polymerase (RdRP) gene and the viral load with quantitative real-time polymerase chain reaction (qRT-PCR), and to assess the neutralization of the SARS-CoV-2 spike receptor binding on cell culture assay. Interestingly, the mixture (H.E.
) of 100 mg/mL of H. perforatum
was tested too on SARS-CoV-2 and showed crucial anti-viral activity competing H. perforatum
effects as anti-viral treatments.
The study findings were published on a preprint server and are currently being peer reviewed. https://www.biorxiv.org/content/10.1101/2021.01.11.426295v1
Dr Leena Hussein Bajrai and colleagues from King Abdulaziz University in Jeddah recommend that clinical trials be initiated to investigate the herbs as potential treatments for SARS-CoV-2 infection.
Thailand Medical news had already mentioned about the possibility of using Echinacea as both a prophylaxis and also as a therapeutic agent to treat COVID-19 as early as March 2020. https://www.thailandmedical.news/news/breaking-coronavirus-research-could-echinacea-act-as-a-prophylaxis-against-the-sars-cov-2-coronavirus-more-research-warranted
Though most SARS-COV-2 infections cause mild-to-moderate COVID-19, a substantial proportion leads to severe disease characterized by vasculitis, coagulopathy, and multi-organ damage that can lead to death. Such advanced disease can be caused by the overproduction of certain cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin -6 (IL-6), and interferon-gamma (IFN-γ).
Also although some vaccines protecting against SARS-CoV-2 infection have recently become available, their efficacy is a topic of intense debate, particularly since new variants have arisen in the virus's genomic structure.
Effective antivirals are therefore still urgently needed as treatment approaches, says the team.
The herbal plants H. perforatum or St. John's Wort has long been known for its medicinal effects across a range of bacterial and viral infections.
In vitro and in vivo studies have previously demonstrated the antiviral activity of H. perforatum against infectious bronchitis virus (IBV), hepatitis C, and coronaviruses other than SARS-CoV-2. https://www.tandfonline.com/doi/full/10.3109/13880209.2015.1102948
The three species of Echinacea (Purple cone Flower), namely E. angustifolia, E. purpurea, and E. Pallida, have also traditionally been used as remedies to treat influenza and to boost the immune system.
In vivo and in vitro studies have previously shown that Echinacea influences cytokine production, increases expression of the lymphocyte activation marker CD69, and reduces the severity of illness. https://pubmed.ncbi.nlm.nih.gov/16807880/
Another study conducted in 2009 showed that E. purpurea extract inhibits infection with H5N1 influenza by blocking the receptor-binding activity of the virus. https://pubmed.ncbi.nlm.nih.gov/19912623/
The study team investigated the antiviral effects of H. perforatum and two Echinacea species (E. purpurea and E. angustifolia) on Vero E6 cells incubated with SARS-CoV-2. The effects of treating the cells with a mixture of the herbs (H.E) were also investigated.
The mode of action of these herbs was assessed using three approaches: direct treatment of virus-infected cells, pre-treatment of cells prior to viral infection, and a virucidal activity assay.
qRT-PCR or Quantitative real-time polymerase chain reaction was used to measure the mRNA expression of the RNA-dependent RNA polymerase (RdRP) gene, viral load, and virus neutralization every 12, 16, 24, 36, and 48 hours post-infection.
The study findings showed that when virus-infected cells were treated with the extracts, H. perforatum showed the greatest efficacy, with an IC50 value (concentration that inhibits 50% of target) of 1.56mg/mL, followed by the H.E mixture (IC50: 6.25mg/mL), and Echinacea (IC50: 6.25mg/mL).
Interestingly the greatest reduction in viral load was observed for H. perforatum, followed by the H.E. mixture and Echinacea. Both H. perforatum and the H.E mixture reduced viral load for up to 36 hours, while Echinacea reduced it for up to 24hrs of addition.
Subsequently the cells were incubated with the extracts at 37°C for two hours prior to infection. The effective concentration was highest for H. perforatum, at 1.56 µg/mL, followed by the H.E. mixture (6.25 mg/mL) and Echinacea (6.25 mg/mL).
In the case of the virucidal activity assay, SARS-CoV-2 was incubated with the extracts for two hours before it was added to cells. Again, H. perforatum exhibited the greatest effect, followed by the H.E mixture, and Echinacea. Incubation with H. perforatum or the H.E mixture reduced viral load for more than 48 hours, while Echinacea reduced viral load for up to 36 hours.
Dr Bajrai told Thailand Medical News, "H. perforatum showed the highest inhibitory effect in all three antiviral assays, while Echinacea showed the lowest inhibitory effect.”
The study team says the study provides clear evidence for the first time that a mixture of H. perforatum and Echinacea demonstrates anti-SARS-CoV-2 activity.
The team suggests testing whether the mixture can boost the inhibition of the virus in clinical trials.
This mixture could be useful for treating SARS-CoV-2-infected patients with mild or severe disease and for protecting people who have contact with infected patients, says Dr Bajrai. However, treatment with H. perforatum is preferable since it demonstrated a higher efficacy, they add.
The study team also recommends using either Echinacea or H.E as a prophylactic approach to SARS-CoV-2 infection.
Thailand Medical News warns that no one should attempt to use either of these herbs without a doctor’s supervision as using Echinacea at the wrong times can actually aggravate the COVID-19 disease progression especially in the case of cytokine storms and also H. perforatum is known to interact with a number of prescription drugs.
For those interested in herbal and phytochemical therapeutics to treat COVID-19 , refer to : https://www.thailandmedical.news/articles/covid-19-herbs
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