March 24th, 2020

An article published on February 12, 2020 in Progress in Cardiovascular Diseases proposes the use of nutritional supplements to enhance the body’s type 1 interferon immune response to influenza and other viruses that have RNA, rather than DNA, as their genetic material.

“Activation of toll-like receptor 7 (TLR7) by single-stranded viral RNA trapped within endosomes provides a key stimulus to type 1 interferon induction by RNA viruses,” authors Mark F. McCarty and James J. DiNicolantonio wrote. “Another key mediator of type 1 interferon response is the mitochondrial antiviral-signaling protein (MAVS).”

Based on this and other research findings, McCarty and DiNicolantonio identified the antioxidant compounds lipoic acid, ferulic acid (which occurs in plant foods such as bran) and sulforaphane (formed from a compound in Brassica family vegetables that include broccoli) as nutrients that may enhance TLR7-mediated induction of type 1 interferon. Spirulina or a protein in spirulina extracts known as phycocyanobilin may also improve this response to RNA viruses and has decreased mortality in mice infected with influenza. N-acetyl-L-cysteine (NAC) increases the production of glutathione (which forms part of the antioxidant enzyme glutathione peroxidase-1) and could help protect TLR7 from damage due to oxidation. Selenium, an element that is present in glutathione peroxidase-1, may also be beneficial. The authors noted that antioxidants in general may be useful due to their ability to dampen excessive lung inflammation induced by viruses.

Another mechanism of type 1 interferon response, activation of mitochondrial antiviral-signaling protein (MAVS), can be upregulated by a relatively high dose of glucosamine, a compound that supports joint health. The addition of glucosamine to the diet of mice infected with influenza significantly improved survival while failing to protect those that were genetically modified to lack MAVS. “This striking new finding points to the possibility that high-dose glucosamine supplementation might aid prevention and control of RNA virus infections,” McCarty and DiNicolantonio remarked.

“Administration of spirulina (or a spirulina extract enriched in phycocyanobilin), a phase 2 inducer (such as ferulic acid, lipoic acid, or sulforaphane), N-acetyl-L-cysteine, selenium, and high-dose glucosamine, in adequate doses, might be expected to help prevent and control RNA virus infections by amplifying the signaling functions of TLR7 and MAVS in evoking type 1 interferon production,” they concluded. They added that beta-glucan from brewer’s yeast, zinc and elderberry (which has an antiviral effect that may be partly mediated by ferulic acid) are further practical nutritional strategies for coping with RNA virus infections.

 “The agents I suggest appear to be overall beneficial for general health - particularly cardiovascular health - and are therefore appropriate for use in primary prevention,” McCarty said.