Two Resveratrol Oligomers Inhibit Cathepsin L Activity to Suppress SARS-CoV-2 Entry.

Cell entry of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) depends on specific host cell proteases, which are the key targets for preventing and treating viral infections. Herein, we describe miyabenol C and trans-ε-viniferin, two resveratrol oligomers that specifically inhibit SARS-CoV-2 entry by targeting host protease cathepsin L. Several cell-based assays were used to demonstrate the effect of resveratrol oligomers, and their target was identified via screening of antiviral targets. Molecular docking analysis suggested that the oligomers could occupy the active cavity of cathepsin L. The surface plasmon resonance assay showed that the equilibrium dissociation constant (KD) values of miyabenol C-cathepsin L and trans-ε-viniferin-cathepsin L were 5.54 and 8.54 µM, respectively, indicating their excellent binding ability for cathepsin L. Our study demonstrated the potential application of resveratrol oligomers as lead compounds in controlling SARS-CoV-2 infection by targeting cathepsin L.

Identification of hACE2-interacting sites in SARS-CoV-2 spike receptor binding domain for antiviral drugs screening.

The key structure of the interface between the spike protein of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and human angiotensin-converting enzyme 2 (hACE2) acts as an essential switch for cell entry by the virus and drugs targets. However, this is largely unknown. Here, we tested three peptides of spike receptor binding domain (RBD) and found that peptide 391-465 aa is the major hACE2-interacting sites in SARS-CoV-2 spike RBD. We then identified essential amino acid residues (403R, 449Y, 454R) of peptide 391-465 aa that were critical for the interaction between the RBD and hACE2. Additionally, a pseudotyped virus containing SARS-CoV-2 spike with individual mutation (R454G, Y449F, R403G, N439I, or N440I) was determined to have very low infectivity compared with the pseudotyped virus containing the wildtype (WT) spike from reference strain Wuhan 1, respectively. Furthermore, we showed the key amino acids had the potential to drug screening. For example, molecular docking (Docking) and infection assay showed that Cephalosporin derivatives can bind with the key amino acids to efficiently block infection of the pseudoviruses with wild type spike or new variants. Moreover, Cefixime inhibited live SARS-CoV-2 infection. These results also provide a novel model for drug screening and support further clinical evaluation and development of Cephalosporin derivatives as novel, safe, and cost-effective drugs for prevention/treatment of SARS-CoV-2.

Neutrophil to lymphocyte ratio as prognostic and predictive factor in patients with coronavirus disease 2019: A retrospective cross-sectional study.

This retrospective study was designed to explore whether neutrophil to lymphocyte ratio (NLR) is a prognostic factor in patients with coronavirus disease 2019 (COVID-19). A cohort of patients with COVID-19 admitted to the Tongren Hospital of Wuhan University from 11 January 2020 to 3 March 2020 was retrospectively analyzed. Patients with hematologic malignancy were excluded. The NLR was calculated by dividing the neutrophil count by the lymphocyte count. NLR values were measured at the time of admission. The primary outcome was all-cause in-hospital mortality. A multivariate logistic analysis was performed. A total of 1004 patients with COVID-19 were included in this study. The mortality rate was 4.0% (40 cases). The median age of nonsurvivors (68 years) was significantly older than survivors (62 years). Male sex was more predominant in nonsurvival group (27; 67.5%) than in the survival group (466; 48.3%). NLR value of nonsurvival group (median: 49.06; interquartile range [IQR]: 25.71-69.70) was higher than that of survival group (median: 4.11; IQR: 2.44-8.12; P < .001). In multivariate logistic regression analysis, after adjusting for confounding factors, NLR more than 11.75 was significantly correlated with all-cause in-hospital mortality (odds ratio = 44.351; 95% confidence interval = 4.627-425.088). These results suggest that the NLR at hospital admission is associated with in-hospital mortality among patients with COVID-19. Therefore, the NLR appears to be a significant prognostic biomarker of outcomes in critically ill patients with COVID-19. However, further investigation is needed to validate this relationship with data collected prospectively.