Can nutraceuticals help defend us against viral infections?
In the very recent article currently being published in the journal Progress in Cardiovascular Diseases, McKarty and Di Nicolantonio (Catalytic Longevity Foundation, Mid America Heart Institute, St Luke’s Hospital, USA) comment on two innovative discoveries in the biochemical field, which can potentially be reflected in the nutraceutical field, about the body’s defense mechanisms against RNA viruses, including coronavirus.
The authors highlight that some classes of natural active ingredients, commonly used in the nutraceutical field, are able to positively interact with some key elements of the production of interferon 1 and are therefore able to contribute to enhancing and / or regulating the mediated response from this defense cytokine that “interferes” with the growth and propagation of viruses.
The production of interferon 1 following contact with the antigen is regulated by a very complex pathway that involves various receptors and transcription factors, among which are of particular importance: TLR7 (Toll-like receptor 7) and IRF3 (Interferon regulatory factor 3 ). In the presence of strong oxidative stimuli these transcription factors can undergo alterations which result, in cascade, in an inhibition of the production of interferon with consequent lowering of the physiological levels of defense. One of the most common alterations concerns the structure of cysteine at position 98 (Cys98) of TLR7, whose oxidation compromises its correct signaling capacity.
Actives such as ferulic acid, lipoic acid and phycobilins contained in the spirulina algae can specifically preserve the oxidation of Cys98 through synergistic and complementary mechanisms of action of inhibition of oxidative stimuli. The administration of N-acetylcysteine (NAC) can also be very important, particularly in the elderly who are subject to physiological drops in intracellular levels of glutathione, a cofactor that helps restore the native structure of Cys98 in TLR7 and whose production is stimulated by ‘taking NAC.
Another important mechanism on which dietary supplementation can act to enhance the immune defenses concerns the transcription factor IRF3 (Interferon regulatory factor 3). This transcription factor is activated by adding a residue of N-acetylglucosamine to MAVS (mitochondrial antiviral-signaling protein), a key step in regulating the production of interferon 1. The administration of glucosamine, favoring this reaction, can amplify the action of MAVS and consequently determine an increase in the production of interferon.
The study also underlines that the correct supply of minerals is fundamental: a selenium deficiency seems to be related to more aggressive symptomatology of the viral infection and favours the mutagenic activity of viruses, while zinc supports the action and proliferation of various immune cells.
Even the administration of active ingredients with antioxidant function can indirectly help the body cope with the infection, helping to counteract the excessive inflammatory reaction in the lung parenchyma. Finally, beta glucan favors the activation of dendritic cells and is associated with an immunostimulating action.
