Friday Hope: Garlic: More Than Just the Doherty Institute Study

Interestingly, I cannot find the actual study, just a Statement from the Doherty Institute.

Allicin treatment of SARS-CoV-2 infected Vero E6 cells inhibits viral replication.(A-C) Vero E6 cells were infected with SARS-CoV-2 at a MOI of 0.01. After 24 h p.i. viral replication was analyzed by determination of infectious viral particles or viral RNA in the supernatant. (A) Comparison of different allicin treatment options: Untreated Vero E6 cells infected with SARS-CoV-2 as control (SARS), SARS-CoV-2 pre-treated with 50 μM allicin for 30 min prior to infection of host cells (All+SARS), host cells pre-treated with 50 μM allicin for 30 min prior to infection with SARS-CoV-2 (All+Vero) and SARS-CoV-2 infected host cells treated with 50 μM allicin p.i. (All+Vero p.i.). Allicin treatment p.i. significantly decreased the number of infectious viral particles. (B, C) The amount of viral RNA (B) and infectious viral particles (C) was determined after treatment of SARS-CoV-2 infected Vero E6 cells with 50 and 75 μM allicin p.i. Increased allicin doses significantly inhibit SARS-CoV-2 replication. The results A-C are from 3 biological replicates with 2 technical replicates for B. Error bars represent the SD. p-values were calculated using an unpaired two-tailed t-Test.*p<0.05. ***p<0.001. 

Allicin inhibits SARS-CoV-2 replication and abrogates the antiviral host response in the Calu-3 proteome 
https://www.biorxiv.org/content/10.1101/2021.05.15.444275v2.full 

If you have been following the news over the past few days, you will undoubtedly have heard of the stunning research out of the Doherty Institute in Melbourne, under contract from the Australian Garlic Producers.  

The type of garlic has not been disclosed. All that has been revealed is that it is grown in a small farming town south of Mildura. The results, however, are anything far from small. 

Dr Julie McAuley, manager of the Doherty’s high containment facility COVID-19 research lab, said the results were striking. 

“We wanted to know if these strains had the possibility of killing COVID-19,” she told The Australian Financial Review. “I thought it might fail miserably. We blindly tested over 20 varieties. We found one of AGP’s products could reduce the infectious titre of SARS-CoV-2 and influenza by 3-log-fold (99.9 per cent). We barely detected any remaining virus genome, indicating nearly complete virucidal activity.” 

Australian garlic kills COVID-19, says Doherty Institute 
https://www.afr.com/life-and-luxury/health-and-wellness/doherty-finds-garlic-kills-covid-20230530-p5dcgn 

Yet, the idea that garlic would be beneficial against COVID-19 is not a new one. In fact, all the way back in 2020 a Letter to the Editor of the BMC Nutrition Journal made a very astute observation: 

Recently, researchers have realized the structure of the main protease of SARS-CoV-2, a serine-type Mpro (chymotrypsin-like protease (3CLpro)) protease with the kind of amino acids (such as Thr24, Thr26, and Asn119) present in the active site regions (e.g., 6 LU7 and 2GTB). Mpro has a considerable structural similarity (~ 96.0%) between types 1 and 2 of SARS-CoV. Since this protease is responsible for the viral replication and the production functional protein as a result of the proteolytic maturation of SARS-CoV-2, the infection rate may be substantially reduced by hindering the cleavage of the viral polyprotein. In an in silico approach on the inhibitory effect of garlic against SARS-CoV-2, seven OSCs of alliin, S-(allyl/ methyl/ethyl/propyl)-cysteine, S-propyl L-cysteine, and S-ally-mercapto-cysteine were considered as possible constitutes to inhibit the Mpro of SARS-CoV-2 through H-bonds with this protease. Molecular docking analysis showed that alliin among other OSCs has higher anti-viral potential to prevent COVID-19. 

Garlic (Allium sativum L.): a potential unique therapeutic food rich in organosulfur and flavonoid compounds to fight with COVID-19 
https://nutritionj.biomedcentral.com/articles/10.1186/s12937-020-00643-8 

What the above means, is that garlic prevents the virus from taking its amino chain and breaking it up into useful protein to create new viruses. Think of it as not allowing molten steel to be formed into parts of a car frame. The molten steel alone is, obviously, quite useless to make a car. 

Additional evidence of garlic inhibiting SARS-CoV-2 replication comes from the study cited in the introductory graphic. 

However, biocompatible allicin doses efficiently inhibited viral replication in both cell lines. Proteome analyses of SARS-CoV-2 infected Calu-3 cells revealed a strong induction of the antiviral interferon-stimulated gene (ISG) signature (e.g. cGAS, Mx1, IFIT, IFIH, IFI16, IFI44, 2’5’OAS and ISG15), pathways of vesicular transport, tight junctions (KIF5A/B/C, OSBPL2, CLTC1, ARHGAP17) and ubiquitin modification (UBE2L3/5), as well as reprogramming of host metabolism, transcription and translation. Allicin abrogated the ISG host response and reverted the host cellular pathways to levels of uninfected Calu-3 cells, confirming the antiviral and immunomodulatory activity of allicin in the host proteome. Thus, biocompatible doses of allicin could be promising for protection of lung cells against SARS-CoV-2. 

Allicin inhibits SARS-CoV-2 replication and abrogates the antiviral host response in the Calu-3 proteome 
https://www.biorxiv.org/content/10.1101/2021.05.15.444275v2.full 

Clearly, more evidence is needed to determine the large-scale benefits of garlic use. Also, dosing with garlic needs to be done carefully as too much (as with most compounds) can be toxic. The research does look promising. Which makes it even more confusing that this is all the Doherty institute has to say about the study: 

Yet, as with most natural therapeutics for COVID, the “skeptics” are indeed, quite loud. 

On a personal note, I will be adding garlic extract to my daily regimen. 

As always, immense thanks to my supporters. Your generosity allows me the time to research and discover.