ABSTRACT
Recently emerged coronavirus, known as SARS-CoV-2 or Covid-19 is considered as a serious threat for human health. Due to unavailable specific drugs for this virus, there is an urgent need for supportive cares. Epigenetic immune boosting approaches and developing anti-inflammatory agents by gut-associated bioactive macronutrients can be plausible protective cares for COVID-19. Suitable intake of bioactive macronutrients including prebiotics, fatty acids, proteins and branched-chain amino acids may result in anti-viral responses through modulating macrophages and dendritic cells via Toll-like receptors, decreasing viral load, inactivating the enveloped viruses, increasing the anti-inflammatory metabolites and inhibiting the proliferation of microbial organisms. Bioactive macronutrients may help in promotion of immunological responses and recovery acceleration against Covid-19. This review focuses on the mechanisms of bioactive macronutrients and related clinical trials on enveloped viruses with emphasis on gut-microbiome-immune axis. Macronutrients and this axis may be conducive strategies to protect host against the viral infection.
ABSTRACT
Coronaviruses have caused worldwide outbreaks in different periods. SARS (severe acute respiratory syndrome) was the first emerged virus from this family, followed by MERS (Middle East respiratory syndrome) and SARS-CoV-2 (2019-nCoV or COVID 19), which is newly emerged. Many studies have been conducted on the application of chemical and natural drugs for treating these coronaviruses and they are mostly focused on inhibiting the proteases of viruses or blocking their protein receptors through binding to amino acid residues. Among many substances which are introduced to have an inhibitory effect against coronaviruses through the mentioned pathways, natural components are of specific interest. Secondary and primary metabolites from plants, are considered as potential drugs to have an inhibitory effect on coronaviruses. IC50 value (the concentration in which there is 50% loss in enzyme activity), molecular docking score and binding energy are parameters to understand the ability of metabolites to inhibit the specific virus. In this study we reviewed 154 papers on the effect of plant metabolites on different coronaviruses and data of their IC50 values, molecular docking scores and inhibition percentages are collected in tables. Secondary plant metabolites such as polyphenol, alkaloids, terpenoids, organosulfur compounds, saponins and saikosaponins, lectins, essential oil, and nicotianamine, and primary metabolites such as vitamins are included in this study.