Effects of yogurt containing probiotics on respiratory virus infections: Influenza H1N1 and SARS-CoV-2.

Respiratory virus infections are an escalating issue and have become common worldwide. Influenza and COVID-19 are typical infectious respiratory diseases, and they sometimes lead to various complications. In a situation in which no established drug or treatment exists, consumption of proper food might be beneficial in maintaining health against external infections. We studied the potential effects of mixtures of probiotic strains on various viral infections. The purpose of this study was to assess the ability of yogurt containing probiotics to reduce the risk of respiratory viruses such as influenza H1N1 and SARS-CoV-2 infection. First, we performed in vitro tests using infected Madin-Darby canine kidney (MDCK) and Vero E6 cells, to evaluate the potential effects of yogurt containing high-dose probiotics against influenza H1N1 and SARS-CoV-2 infection. The yogurt significantly reduced plaque formation in the virus-infected cells. We also performed in vivo tests using influenza H1N1-infected C57BL/6 mice and SARS-CoV-2-infected Syrian golden hamsters, to evaluate the potential effects of yogurt. Yogurt was administered orally once daily during the experimental period. Yogurt was also administered orally as pretreatment once daily for 3 wk before viral infection. Regarding influenza H1N1, it was found that yogurt caused an increase in the survival rate, body weight, and IFN-γ, IgG1, and IL-10 levels against viral infection and a decrease in the inflammatory cytokines TNF-α and IL-6. Although the SARS-CoV-2 copy number was not significantly reduced in the lungs of yogurt-treated SARS-CoV-2-infected hamsters, the body weights and histopathological findings of the lungs were improved in the yogurt-treated group. In conclusion, we suggest that consumption of yogurt containing probiotics can lead to beneficial effects to prevent respiratory viral infections.

Therapeutic effects of shibashin misena® against fine-dust-induced pulmonary disorders in mice.

INTRODUCTION: In recent decades, fine-dust particulate matter (FM) has become a potential health hazard, causing various pathological respiratory disorders around the world. Inflammation induced by FM is regarded as a major cause of respiratory disorder in humans. The purpose of this study was to evaluate the therapeutic efficacy of Shibashin Misena®, a functional food composed of various bioactive ingredients, on FM-induced respiratory disorders in mice. MATERIALS AND METHODS: Briefly, 40 mice were divided equally into four groups: normal controls (NC); FM-induced control group (FC); FM group treated with Shibashin Misena® 0.1 mL/head/day (FM0.1); FM group treated with Shibashin Misena® 0.2 mL/head/day (FM0.2). RESULTS: FM significantly induced TNF-α, IL-17A, IL-1ß, and TGF-ß in bronchoalveolar lavage fluid (BALF) collected from the FM mice. Compared with FC, Shibashin Misena® decreased TNF-α, IL-17A, and IL-1ß levels in BALF, and histopathologic evaluations revealed that Shibashin Misena® treatment significantly reduced inflammatory-cell infiltration and fibrosis related collagen deposition in lung tissue. CONCLUSION: This study demonstrated that Shibashin Misena® decreased FM-induced inflammation and fibrosis in lung tissue. Thus, Shibashin Misena® could be an effective supplement to prevent or improve FM-induced pulmonary disorders.