20 Apr Gut microbes fighting influenza
A particular gut microbe can prevent severe flu infections in mice by breaking down flavonoids commonly found in foods such as blueberries, black tea and red wine.
Researchers at Washington University School of Medicine found that not only does the stomach microbe prevent infection but is also effective in staving off severe damage from flu when the interaction occurs prior to infection with the influenza virus.
Flavonoids have long been thought to have protective properties that help regulate our immune system to fight infection. There has also been previous evidence to suggest that the gut microbiome may be important in protecting against severe influenza infection. As flavonoids are commonly found in our diets, an important implication for the scientists study was to find whether flavonoids work with gut microbes to prevent against viral infections.
The research group screened human gut microbes to identify flavonoid metabolising microbes. Clostridium orbiscindens was found to be such a candidate, which degrades flavonoids to produce the metabolite desaminotyrosine (DAT). DAT is known to enhance interferon signalling, a pathway which plays a crucial role in the human immune response through the activities of these cytokines which have antiviral, antiproliferative and immunomodulatory effects.
Given the role of DAT enhancing immune response pathways, the researchers treated mice with DAT prior to infecting them with influenza virus. It was observed that although the DAT treatment did not prevent flu infection itself, the severity of infection from damage to lung tissue caused by immune responses was decreased.
This strategy may prove beneficial in the future in combination with vaccination, as it targets the immune response to the virus, not the virus itself which develops drug resistance through mutation.
With winter flu season sneaking up upon us, it may not be a bad idea to sip on black tea and eat foods high in flavonoids. As long as you have a healthy balance of these gut microbes you may just be able to help your body beat the flu blues this season.
Washington University School of Medicine. “Natural compound coupled with specific gut microbes may prevent severe flu: Mouse study reveals how gut microbes fight influenza.” ScienceDaily. ScienceDaily, 3 August 2017. <www.sciencedaily.com/releases/2017/08/170803141048.htm>.
Ashley L. Steed, George P. Christophi, Gerard E. Kaiko, Lulu Sun, Victoria M. Goodwin, Umang Jain, Ekaterina Esaulova, Maxim N. Artyomov, David J. Morales, Michael J. Holtzman, Adrianus C. M. Boon, Deborah J. Lenschow, Thaddeus S. Stappenbeck. The microbial metabolite desaminotyrosine protects from influenza through type I interferon. Science, 2017; 357 (6350): 498 DOI: 10.1126/science.aam5336