Covid, Pregliasco: ‘Interesting data on lactoferrin from in vitro study’

“Lactoferrin, a natural protein found in bovine milk, in combination with a specific probiotic, Lactobacillus paracasei DG, contained in the Enterolactis product, could help prevent Covid-19 and alleviate symptoms associated with the infection. an in vitro study on lactoferrin are very interesting. ”This was stated to Adnkronos Salute by the virologist of the University of Milan, Fabrizio Pregliasco, Health Director at the Galeazzi Orthopedic Institute in Milan, one of the authors of the research published last August in the journal Gut microbes. In the study, in which the Universities of Padua and Milan participated, the antiviral immune effects and the anti Sars-CoV-2 activity of three probiotic strains of Lacticaseibacillus (L. paracasei DG, L. rhamnosus GG, L. paracasei LPC-S01), alone or in combination with lactoferrin in vitro, using an intestinal epithelial cell line Caco-2, which expresses the re Ace2 receiver. The intestine, in fact, represents another viral target organ that supports the replication of SarS-CoV-2. SarS-CoV-2 infection spreads mainly through droplets and respiratory secretions, however “the intestinal tract – explains Pregliasco – could be another potential infection channel, and in about 17% of cases respiratory symptoms they are associated with gastrointestinal disorders. These data suggest that the gastrointestinal tract could be a location for viral activity and replication ”. Probiotics act “both on the innate immune system – reiterates Pregliasco – and on the acquired one and have the potential to reduce the severity of infections in the gastrointestinal tract and in the upper respiratory tract. They exhibit their antiviral activity through direct interaction with the virus, the production of antiviral metabolites, the stimulation of the type I interferon response and the production of antibodies against the virus. The potential of probiotics in reducing the risk and severity of viral respiratory tract infections is also supported by clinical and experimental studies of influenza, rhinovirus, and respiratory syncytial virus. So far these effects had not been tested on Covid-19, but some probiotics had demonstrated antiviral activity against other coronaviruses. Lactoferrin, a substance of natural origin, has shown antiviral, immunomodulatory and anti-inflammatory effects, so our hypothesis, confirmed by the study, concerned the possible synergy between probiotic and lactoferrin “. The results confirm that the three probiotics stimulate at different levels the antiviral activity, but L. paracasei DG is the most effective and promising in terms of antiviral immunomodulatory activity and able to induce the expression of genes involved in the antiviral response, such as IFNA1 and IFNB1 (antiviral cytokines), TLR7 and IFIH1 (involved in virus recognition), IRF7 and MAVS (participate in the signaling pathways of the antiviral response). “Our work demonstrates that the Lacticaseibacillus paracasei DG strain is a promising candidate with potential for prophylaxis against infection,” Pregliasco points out, adding: “Not only is the antiviral activity of L. paracasei DG confirmed, but also its ability to suppress d el 50% the in vitro replication of Sars-CoV-2. Lactic acid bacteria, such as L. paracasei DG, produce a wide variety of antimicrobial compounds, such as hydrogen peroxide, lactic acid and bactericidal substances, which are capable of reducing viral load. “These results” were not observed with the other two. strains tested, demonstrate how important it is to choose the right probiotic – continues the expert – The results are decidedly positive, so the expectation of confirmation in a subsequent in vivo experiment is growing. “The beneficial and antiviral effects of probiotics and lactoferrin in humans lead us to think that their association can confirm the data of our work also in a future in vivo study. “Regarding the possible future clinical developments of the study, Pregliasco has no doubts:” On Sars-CoV-2 this research is important but it is clear that we do not want to be the therapeutic alternative in the face of a need for studies, clinical trials and all the necessary insights. As I had already seen for a However, other probiotics are confirmed to be used as adjuvants in terms of prevention and strengthening of the immune defenses “.