The role of probiotics, live bacteria, in modulating the intestinal microbiota of the immune system and preventing infections is now well known.
The composition of the intestinal microbiota can influence the severity of COVID-19 and also the way the immune system responds to infection.
According to a reviewby the "A. Gemelli" Polyclinic in Rome, MICROBIOTA could represent an incredible new therapeutic option or, at least, an adjuvant therapeutic choice to mitigate SARS-CoV-2 disease.
The hypothesis is that a proper diet and appropriate supplementation with prebiotics and probiotics can rebalance thecomposition of intestinal bacteria and limit Covid-19 infection.
An important role in the migration of the viral agent from the airways, which are most in contact with the outside world and therefore easily infected, to the intestine is probably due to the presence of an "gut-lung axis." The interaction could be mediated by the respective local bacterial populations, which would also explain the different susceptibility to infection among individuals. Considering the gastrointestinal tract as a site of infection and, consequently, of possible transmission seems to be becomingfundamental in the proper management of the emergency.
Gastrointestinal symptoms and coronavirus
Intestinal involvement is demonstrated not only bygastrointestinal symptoms that occur in approximately 40% of patients(diarrhea, nausea, vomiting, abdominal pain), but also by thepresence of viral RNA inpatients'feces, sometimes even when respiratory tests are negative. Specifically, the main target of the virus, the ACE2 (Angiotensin Conversion Enzyme 2) enzyme, is expressed mainly in lung cells but also in intestinal cells. Once the infection has started, an inflammatory and immune cascade is also activated with the release of cytokines such as IL-12, IL6, IL17, and tumor necrosis factor [TNF], which mediate the local and systemic response. However, the microbiotais also an important player in the inflammatory and immune landscape .
Thegut microbiotais fundamental in the development and regulation of the immune system, which, in turn, influences its composition and characteristics.
Despite the significantly lower number of bacteria that populate the respiratory tract compared to the gastrointestinal tract, the lung microbiota shares most of the phyla and their relative abundance ratios with the gut microbiota.
They also seem to share a role in promoting the maturation and homeostasis of the local immune system. Intestinaldysbiosiscould thereforeincrease the likelihood of contracting COVID-19 infection and/or influence the severity of symptomsby mediating the immune response.
Recent evidence also supports a genuinebidirectional connection between the two microbiomes (lung and intestinal), known as the "gut-lung axis." For example, intestinal microbiota transplantation has been shown to impact lung bacterial composition. The lymphatic system also appears to be involved. In fact, in the event of inflammation, lymphoid cells residing in the intestine and responsible for repair can migrate to the respiratory system.
In patients with acute respiratory distress syndrome (ARDS), which is also typical of this infection, the course of the disease has in fact shown a correlation with the composition of the intestinal microbiota. In the specific case of COVID patients, however, this relationship remains to be proven. Today, given the short time that has passed since the start of the pandemic, it is not yet possible to state with certainty the involvement of the gut-lung axis in cases of SARS-CoV-2, but the hypothesis of intervening on the intestinal bacterial component to improve symptoms or reduce susceptibility to infection is now gaining ground.
What is certain is that it is possible to prevent infection by eating a healthy diet, resuming physical activity, relieving nervous tension, and considering adequate PROBIOTIC SUPPLEMENTATION.
