Potential Therapeutic Effect of Micrornas in Extracellular Vesicles from Mesenchymal Stem Cells against SARS-CoV-2.

Extracellular vesicles (EVs) are cell-released, nanometer-scaled, membrane-bound materials and contain diverse contents including proteins, small peptides, and nucleic acids. Once released, EVs can alter the microenvironment and regulate a myriad of cellular physiology components, including cell-cell communication, proliferation, differentiation, and immune responses against viral infection. Among the cargoes in the vesicles, small non-coding micro-RNAs (miRNAs) have received attention in that they can regulate the expression of a variety of human genes as well as external viral genes via binding to the complementary mRNAs. In this study, we tested the potential of EVs as therapeutic agents for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. First, we found that the mesenchymal stem-cell-derived EVs (MSC-EVs) enabled the rescue of the cytopathic effect of SARS-CoV-2 virus and the suppression of proinflammatory responses in the infected cells by inhibiting the viral replication. We found that these anti-viral responses were mediated by 17 miRNAs matching the rarely mutated, conserved 3'-untranslated regions (UTR) of the viral genome. The top five miRNAs highly expressed in the MSC-EVs, miR-92a-3p, miR-26a-5p, miR-23a-3p, miR-103a-3p, and miR-181a-5p, were tested. They were bound to the complemented sequence which led to the recovery of the cytopathic effects. These findings suggest that the MSC-EVs are a potential candidate for multiple variants of anti-SARS-CoV-2.

Pregnancy Outcome, Antibodies, and Placental Pathology in SARS-CoV-2 Infection during Early Pregnancy.

There are reports that pregnant women infected with SARS-CoV-2 not only have increased morbidity but also increased complications and evidence of maternal and fetal vascular malperfusion on placental pathology. This was a retrospective study of pregnant women diagnosed with SARS-CoV-2 infection after March 2020. The results of reverse transcription polymerase chain reaction testing and IgM and IgG antibody testing of the amniotic fluid, cord blood, placenta, and maternal blood were confirmed at delivery. Placentas were evaluated histopathologically. The study included seven pregnant women diagnosed with SARS-CoV-2 infection during pregnancy at a mean gestational age of 14.5 weeks. Out of the seven women, five were infected during the first trimester. The mean gestational age at delivery was 38.4 weeks. The reverse transcription polymerase chain reaction results for maternal plasma, cord blood, placenta, and amniotic fluid were negative and IgG antibodies were detected in maternal plasma and cord blood. On placental pathology, maternal vascular malperfusion was found in only one case, fetal vascular malperfusion in four cases, and inflammatory changes were found in two cases. Pregnancy outcomes for women diagnosed with SARS-CoV-2 infection during early pregnancy are positive and it is likely that maternal antibodies are passed to the fetus, which results in a period of immunity.

Impacts of the COVID-19 Pandemic on Food Security and Diet-Related Lifestyle Behaviors: An Analytical Study of Google Trends-Based Query Volumes.

The severe acute respiratory syndrome coronavirus (SARS-CoV)-2 disease (COVID)-19 is having profound effects on the global economy and food trade. Limited data are available on how this pandemic is affecting our dietary and lifestyle-related behaviors at the global level. Google Trends was used to obtain worldwide relative search volumes (RSVs) covering a timeframe from before the COVID-19 pandemic 1 June 2019 to 27 April 2020. Spearman's rank-order correlation coefficients were used to measure relationships between daily confirmed cases and aforementioned RSVs between 31 December 2019 and 15 April 2020. RSV curves showed increased interest in multiple keywords related to dietary and lifestyle behaviors during the COVID-19 lockdown period in March and April 2020. Spearman's correlation analysis showed that the strongest variables in each keyword category were (1) food security (food shortage: r = 0.749, food bank: r = 0.660, and free food: r = 0.555; all p < 0.001), (2) dietary behaviors (delivery: r = 0.780, restaurant: r = -0.731, take-away: r = 0.731, and food-delivery: r = 0.693; all p < 0.001), (3) outdoor-related behaviors (resort: r = -0.922, hotel: r = -0.913, cinema: r = -0.844, park: r = -0.827, fitness: r = -0.817, gym: r = -0.811; plant: r = 0.749, sunbathing: r = 0.668, and online: r = 0.670; all p < 0.001), and (4) immune-related nutrients/herbs/foods (vitamin C: r = 0.802, vitamin A: r = 0.780, zinc: r = 0.781, immune: r = 0.739, vitamin E: r = 0.707, garlic: r = 0.667, omega-3 fatty acid: r = -0.633, vitamin D: r = 0.549, and turmeric: r = 0.545; all p < 0.001). Restricted movement has affected peoples' dietary and lifestyle behaviors as people tend to search for immune-boosting nutrients/herbs and have replaced outdoor activities with sedentary indoor behaviors.