Caffeic acid derivatives (CAFDs) as inhibitors of SARS-CoV-2: CAFDs-based functional foods as a potential alternative approach to combat COVID-19

BackgroundSARS-CoV-2, an emerging strain of coronavirus, has affected millions of people from all the continents of world and received worldwide attention. This emerging health crisis calls for the urgent development of specific therapeutics against COVID-19 to potentially reduce the burden of this emerging pandemic.PurposeThis study aims to evaluate the anti-viral efficacy of natural bioactive entities against COVID-19 via molecular docking and molecular dynamics simulation.MethodsA library of 27 caffeic-acid derivatives was screened against 5 proteins of SARS-CoV-2 by using Molegro Virtual Docker 7 to obtain the binding energies and interactions between compounds and SARS-CoV-2 proteins. ADME properties and toxicity profiles were investigated via www.swissadme.ch web tools and Toxtree respectively. Molecular dynamics simulation was performed to determine the stability of the lead-protein interactions.ResultsOur obtained results has uncovered khainaoside C, 6-O-Caffeoylarbutin, khainaoside B, khainaoside C and vitexfolin A as potent modulators of COVID-19 possessing more binding energies than nelfinavir against COVID-19 M^pro, Nsp15, SARS-CoV-2 spike S2 subunit, spike open state and closed state structure respectively. While Calceolarioside B was identified as pan inhibitor, showing strong molecular interactions with all proteins except SARS-CoV-2 spike glycoprotein closed state. The results are supported by 20 ns molecular dynamics simulations of the best complexes.ConclusionThis study will hopefully pave a way for development of phytonutrients-based antiviral therapeutic for treatment or prevention of COVID-19 and further studies are recommended to evaluate the antiviral effects of these phytochemicals against SARS-CoV-2 in in vitro and in vivo models.     

Chemical constituents from Valeriana jatamansi

Phytochemical study of Valeriana jatamansi Jones afforded 45 compounds, including twenty-three iridoids (1–23), five sesquiterpenes (24–28), three steroids (29–31) and fourteen lignins (32–45). The structures of these compounds were assigned by detailed interpretation of spectroscopic data (1D and 2D NMR, HRESIMS) and comparisons with the published data. This is the first report of isolation of compounds (1–6, 10, 21, 25, 41, 43, 44, 45) from Valerianaceae, compounds (13, 27, 39) within the genus Valeriana and compound 30 from V. jatamans. The chemotaxonomic data can support the genus Valeriana being accepted as a member of transitional taxa between the family Valerianaceae and Caprifoliaceae.     

Inhibition of HECT E3 ligases as potential therapy for COVID-19

SARS-CoV-2 is responsible for the ongoing world-wide pandemic which has already taken more than two million lives. Effective treatments are urgently needed. The enzymatic activity of the HECT-E3 ligase family members has been implicated in the cell egression phase of deadly RNA viruses such as Ebola through direct interaction of its VP40 Protein. Here we report that HECT-E3 ligase family members such as NEDD4 and WWP1 interact with and ubiquitylate the SARS-CoV-2 Spike protein. Furthermore, we find that HECT family members are overexpressed in primary samples derived from COVID-19 infected patients and COVID-19 mouse models. Importantly, rare germline activating variants in the NEDD4 and WWP1 genes are associated with severe COVID-19 cases. Critically, I3C, a natural NEDD4 and WWP1 inhibitor from Brassicaceae, displays potent antiviral effects and inhibits viral egression. In conclusion, we identify the HECT family members of E3 ligases as likely novel biomarkers for COVID-19, as well as new potential targets of therapeutic strategy easily testable in clinical trials in view of the established well-tolerated nature of the Brassicaceae natural compounds.Subject terms: Infection, Medical genomics     

Conferring resistance to parasitic witchweed by shifting strigolactone biosynthesis

Strigolactones from the exudates of maize root induce germination of the parasitic witchweed Striga. Recently, Li et al. characterized the biosynthesis pathway of two strigolactones, zealactol and zealactonoic acid, which induce less Striga germination than the major maize strigolactone, zealactone. This study provides a promising strategy for plant protection against parasitic witchweed.     

Dual biocontrol potential of the entomopathogenic fungus Akanthomyces muscarius against Thaumetopoea pityocampa and plant pathogenic fungi

Akanthomyces spp. species are known for their capacity to biocontrol of certain insects and plant pathogens; however, their ability to biocontrol the pine processionary (Thaumetopoea pityocampa) and certain phytopathogenic fungi belonging to the genera Fusarium and Curvularia have not been studied before. In this study, a strain from Akanthomyces muscarius was isolated from wheat grains and then identified by morphological and molecular tests. The strain was further studied for its capacity to control Thaumetopoea pityocampa larvae through dose-mortality tests, and its ability to control some phytopathogenic fungi strains of the genera Fusarium and Curvularia was studied through direct confrontation tests. Dose-mortality tests at three concentrations of Akanthomyces muscarius against the first instar larvae revealed a mortality of 92.15% after 11 days for the concentration of 2.3 × 10⁶ conidia.ml⁻¹, with a median lethal concentration of 7.6 x10³ conidia.ml^1. Our isolate also showed antifungal activity against these phytopathogenic fungi with inhibition rates ranging from 39.61% to 52.94%. Akanthomyces muscarius proved to be a promising biocontrol agent for plant pests and diseases.     

Viral sponges sequester nucleotide signals to inactivate immunity

Bacteria synthesize specialized nucleotide signals to control anti-phage defense. Two papers – by Huiting et al. and Jenson et al. – now reveal that bacteriophages encode protein ‘sponges’ that sequester cyclic oligonucleotide immune signals and inactivate host antiviral immunity.     

SARS-CoV-2 targets the liver and manipulates glucose metabolism

A recent publication by Barreto and colleagues showed that SARS-CoV-2 directly triggers hyperglycemia by infecting hepatocytes and inducing phosphoenolpyruvate carboxykinase (PEPCK)-dependent gluconeogenesis. Here, we discuss the biological importance of these findings, including the hepatic tropism of SARS-CoV-2. We also comment on the clinical implications of the bidirectional connection between COVID-19 and noncommunicable diseases.     

A comprehensive review on the phytochemistry,pharmacokinetics, and antidiabetic effect of Ginseng

BackgroundRadix Ginseng, one of the well-known medicinal herbs, has been used in the management of diabetes and its complications for more than 1000 years.PurposeThe aim of this review is devoted to summarize the phytochemistry and pharmacokinetics of Ginseng, and provide evidence for the antidiabetic effects of Ginseng and its ingredients as well as the underlying mechanisms involved.MethodsFor the purpose of this review, the following databases were consulted: the PubMed Database (https://pubmed.ncbi.nlm.nih.gov), Chinese National Knowledge Infrastructure (http://www.cnki.net), National Science and Technology Library (http://www.nstl.gov.cn/), Wanfang Data (http://www.wanfangdata.com.cn/) and the Web of Science Database (http://apps.webofknowledge.com/).ResultsGinseng exhibits glucose-lowering effects in different diabetic animal models. In addition, Ginseng may prevent the development of diabetic complications, including liver, pancreas, adipose tissue, skeletal muscle, nephropathy, cardiomyopathy, retinopathy, atherosclerosis and others. The main ingredients of Ginseng include ginsenosides and polysaccharides. The underlying mechanisms whereby this herb exerts antidiabetic activities may be attributed to the regulation of multiple signaling pathways, including IRS1/PI3K/AKT, LKB1/AMPK/FoxO1, AGEs/RAGE, MAPK/ERK, NF-κB, PPARδ/STAT3, cAMP/PKA/CERB and HIF-1α/VEGF, etc. The pharmacokinetic profiles of ginsenosides provide valuable information on therapeutic efficacy of Ginseng in diabetes. Although Ginseng is well-tolerated, dietary consumption of this herb should follow the doctors’ advice.ConclusionGinseng may offer an alternative strategy in protection against diabetes and its complications through the regulations of the multi-targets via various signaling pathways. Efforts to understand the underlying mechanisms with strictly-controlled animal models, combined with well-designed clinical trials and pharmacokinetic evaluation, will be important subjects of the further investigations and weigh in translational value of this herb in diabetes management.     

Sulforaphane inhibits the expression of interleukin-6 and interleukin-8 induced in bronchial epithelial IB3-1 cells by exposure to the SARS-CoV-2 Spike protein

BackgroundA key clinical feature of COVID-19 is a deep inflammatory state known as “cytokine storm” and characterized by high expression of several cytokines, chemokines and growth factors, including IL-6 and IL-8. A direct consequence of this inflammatory state in the lungs is the Acute Respiratory Distress Syndrome (ARDS), frequently observed in severe COVID-19 patients. The "cytokine storm" is associated with severe forms of COVID-19 and poor prognosis for COVID-19 patients. Sulforaphane (SFN), one of the main components of Brassica oleraceae L. (Brassicaceae or Cruciferae), is known to possess anti-inflammatory effects in tissues from several organs, among which joints, kidneys and lungs.PurposeThe objective of the present study was to determine whether SFN is able to inhibit IL-6 and IL-8, two key molecules involved in the COVID-19 "cytokine storm".MethodsThe effects of SFN were studied in vitro on bronchial epithelial IB3-1 cells exposed to the SARS-CoV-2 Spike protein (S-protein). The anti-inflammatory activity of SFN on IL-6 and IL-8 expression has been evaluated by RT-qPCR and Bio-Plex analysis.ResultsIn our study SFN inhibits, in cultured IB3-1 bronchial cells, the gene expression of IL-6 and IL-8 induced by the S-protein of SARS-CoV-2. This represents the proof-of-principle that SFN may modulate the release of some key proteins of the COVID-19 "cytokine storm".ConclusionThe control of the cytokine storm is one of the major issues in the management of COVID-19 patients. Our study suggests that SFN can be employed in protocols useful to control hyperinflammatory state associated with SARS-CoV-2 infection.     

Dual function of the CHS3-CSA1 immune receptor pair

Plant nucleotide-binding leucine-rich repeat (NLR) receptors mediate specific recognition of pathogen effectors to initiate effector-triggered immunity. Recently, studies by Schulze et al., Yang et al., and Gu et al. collectively show that the Arabidopsis (Arabidopsis thaliana) NLR pair CHS3-CSA1 acts through two distinct activation modes to recognize different pathogen effectors, thus revealing the dual function of the CHS3-CSA1 pair in plant disease resistance.     

An 8-week randomized,double-blind,placebo-controlled study to evaluate the efficacy and safety of red Platycodon grandiflorus root extract on enhancement of immune function

BackgroundThe immune-enhancing effects of red Platycodon grandiflorus root extract (RPGE) has been reported in vitro and in vivo, but there are few studies on humans. Therefore, this study aimed to investigate the efficacy and safety of RPGE in enhancing immune function in healthy subjects.Subjects and methodsAn 8-week randomized, double-blind, parallel, placebo-controlled clinical trial was conducted at the Gachon University Gil Medical Center, Incheon, South Korea. A total of 100 adults aged 20–75 years with white blood cell counts of 3000–10,000 cell/µL were randomly divided into two groups (RPGE group, 50 and placebo group, 50) using a computer-generated random list with a 1:1 allocation ratio. The subjects consumed RPGE (2 times/day, 2 tablets/time, 375 mg RPGE powder/tablet) or placebo for 8 weeks. All test foods for the human study were coded and administered under double-blind conditions. The primary outcome was a change in the NK cell activity after 8 weeks of treatment compared to the baseline.ResultsAmong 100 subjects enrolled for the study, 87 completed the study. NK cell activity (p = 0.005) and IFN-γ level (p = 0.003) of the RPGE group (n = 41) were higher than those of the placebo group (n = 46). The findings of the safety assessment revealed absence of clinically significant changes in any test and serious adverse events throughout the study.ConclusionIn conclusion, these results demonstrate the efficacy and safety of RPGE, suggesting it to be a beneficial agent for enhancing immune function in humans.Trial registrationCRIS Registration Number KCT0005945, https://cris.nih.go.kr.     

Shufeng Jiedu,a promising herbal therapy for moderate COVID-19:Antiviral and anti-inflammatory properties,pathways of bioactive compounds,and a clinical real-world pragmatic study

BackgroundShufeng Jiedu capsules (SFJDC), a patented herbal drug composed of eight medicinal plants, is used for the treatment of different viral respiratory tract infectious diseases. Based on its antiviral, anti-inflammatory and immunoregulatory activity in acute lung injury, SFJDC might be a promising candidate for the treatment of COVID-19.PurposeTo evaluate the antiviral and anti-inflammatory properties and to discover the mechanism of action of SFJDC as a potential drug for the treatment of COVID-19. Furthermore, the study should determine the clinical effectiveness of SFJDC for the treatment of COVID-19.DesignWe analyzed the antiviral and anti-inflammatory effects of SFJDC in a HCoV-229E mouse model on lung index, virus load in the lung, the release of cytokines, and on T- and B-lymphocytes. The mechanism of action was further investigated by network analysis. Additionally, we investigated data from a clinical pragmatic real-world study for patients with confirmed COVID-19, to evaluate the clinical effect of SFJDC and to determine the best time to start the treatment.ResultsSFJDC significantly reduced the virus load in the lung of HCoV-229E mice (from 1109.29 ± 696.75 to 0 ± 0 copies/ml), decreased inflammatory factors IL-6, IL-10, TNF-α, and IFN-γ in the lung, and increased the amount of CD4⁺ and CD8⁺ cells in the blood compared to the model group. Network analysis revealed that SFJDC reduces the activity of NFκB via several signaling pathways. Quercetin, wogonin, and polydatin bind directly to the main protease (M^pro) of SARS-CoV-2.Clinical data showed that SFJDC, added to standard antiviral therapy (AVD), significantly reduced the clinical recovery time of COVID-19 and fatigue (from 3.55 ± 4.09 to 1.19 ± 2.28 days) as well as cough (from 5.67 ± 5.64 to 3.47 ± 3.75) days compared to AVD alone. SFJDC therapy was significantly more effective when used within the first 8 days after the onset of symptoms.ConclusionSFJDC might be a promising drug for the treatment of COVID-19, but large-scale randomized, double-blinded, placebo-controlled clinical trials are needed to complement the real-world evidence. It might be beneficial to start SFJDC treatment as early as possible in suspected cases of COVID-19.     

Vitamin D and COVID-19 susceptibility and severity in the COVID-19 Host Genetics Initiative: A Mendelian randomization study

BackgroundIncreased vitamin D levels, as reflected by 25-hydroxy vitamin D (25OHD) measurements, have been proposed to protect against COVID-19 based on in vitro, observational, and ecological studies. However, vitamin D levels are associated with many confounding variables, and thus associations described to date may not be causal. Vitamin D Mendelian randomization (MR) studies have provided results that are concordant with large-scale vitamin D randomized trials. Here, we used 2-sample MR to assess evidence supporting a causal effect of circulating 25OHD levels on COVID-19 susceptibility and severity.Methods and findingsGenetic variants strongly associated with 25OHD levels in a genome-wide association study (GWAS) of 443,734 participants of European ancestry (including 401,460 from the UK Biobank) were used as instrumental variables. GWASs of COVID-19 susceptibility, hospitalization, and severe disease from the COVID-19 Host Genetics Initiative were used as outcome GWASs. These included up to 14,134 individuals with COVID-19, and up to 1,284,876 without COVID-19, from up to 11 countries. SARS-CoV-2 positivity was determined by laboratory testing or medical chart review. Population controls without COVID-19 were also included in the control groups for all outcomes, including hospitalization and severe disease. Analyses were restricted to individuals of European descent when possible. Using inverse-weighted MR, genetically increased 25OHD levels by 1 standard deviation on the logarithmic scale had no significant association with COVID-19 susceptibility (odds ratio [OR] = 0.95; 95% CI 0.84, 1.08; p = 0.44), hospitalization (OR = 1.09; 95% CI: 0.89, 1.33; p = 0.41), and severe disease (OR = 0.97; 95% CI: 0.77, 1.22; p = 0.77). We used an additional 6 meta-analytic methods, as well as conducting sensitivity analyses after removal of variants at risk of horizontal pleiotropy, and obtained similar results. These results may be limited by weak instrument bias in some analyses. Further, our results do not apply to individuals with vitamin D deficiency.ConclusionsIn this 2-sample MR study, we did not observe evidence to support an association between 25OHD levels and COVID-19 susceptibility, severity, or hospitalization. Hence, vitamin D supplementation as a means of protecting against worsened COVID-19 outcomes is not supported by genetic evidence. Other therapeutic or preventative avenues should be given higher priority for COVID-19 randomized controlled trials.

In a Mendelian randomization analysis, Guillaume Butler-Laporte, Tomoki Nakanishi, and colleages study genetic evidence for a relationship between vitamin D and COVID-19 outcomes.     

Revealing Potential Bioactive Compounds and Mechanisms of Lithospermum erythrorhizon against COVID-19 via Network Pharmacology Study

Lithospermum erythrorhizon (LE) is known in Korean traditional medicine for its potent therapeutic effect and antiviral activity. Currently, coronavirus (COVID-19) disease is a developing global pandemic that can cause pneumonia. A precise study of the infection and molecular pathway of COVID-19 is therefore obviously important. The compounds of LE were identified from the Natural Product Activity and Species Source (NPASS) database and screened by SwissADME. The targets interacted with the compounds and were selected using the Similarity Ensemble Approach (SEA) and Swiss Target Prediction (STP) methods. PubChem was used to classify targets linked to COVID-19. The protein–protein interaction (PPI) networks and signaling pathways–targets–bioactive compounds (STB) networks were constructed by RPackage. Lastly, we performed the molecular docking test (MDT) to verify the binding affinity between significant complexes through AutoDock 1.5.6. The Natural Product Activity and Species Source (NPASS) revealed a total of 82 compounds from LE, which interacted with 1262 targets (SEA and STP), and 249 overlapping targets were identified. The 19 final overlapping targets from the 249 targets and 356 COVID-19 targets were ultimately selected. A bubble chart exhibited that inhibition of the MAPK signaling pathway could be a key mechanism of LE on COVID-19. The three key targets (RELA, TNF, and VEGFA) directly related to the MAPK signaling pathway, and methyl 4-prenyloxycinnamate, tormentic acid, and eugenol were related to each target and had the most stable binding affinity. The three bioactive effects on the three key targets might be synergistic effects to alleviate symptoms of COVID-19 infection. Overall, this study shows that LE can play a role in alleviating COVID-19 symptoms, revealing that the three components (bioactive compounds, targets, and mechanism) are the most significant elements of LE against COVID-19. However, the promising mechanism of LE on COVID-19 is only predicted on the basis of mining data; the efficacy of the chemical compounds and the affinity between compounds and the targets in experiment was ignored, which should be further substantiated through clinical trials.     

Feeding the world sustainably: efficient nitrogen use

Globally, overuse of nitrogen (N) fertilizers in croplands is causing severe environmental pollution. In this context, Gu et al. suggest environmentally friendly and cost-effective N management practices and Hamani et al. highlight the use of microbial inoculants to improve crop yields, while reducing N-associated environmental pollution and N-fertilizer use.     

Characteristics and outcomes of hospital admissions for COVID-19 and influenza in the Toronto area

BACKGROUND:Patient characteristics, clinical care, resource use and outcomes associated with admission to hospital for coronavirus disease 2019 (COVID-19) in Canada are not well described.METHODS:We described all adults with COVID-19 or influenza discharged from inpatient medical services and medical–surgical intensive care units (ICUs) between Nov. 1, 2019, and June 30, 2020, at 7 hospitals in Toronto and Mississauga, Ontario. We compared patient outcomes using multivariable regression models, controlling for patient sociodemographic factors and comorbidity level. We validated the accuracy of 7 externally developed risk scores to predict mortality among patients with COVID-19.RESULTS:There were 1027 hospital admissions with COVID-19 (median age 65 yr, 59.1% male) and 783 with influenza (median age 68 yr, 50.8% male). Patients younger than 50 years accounted for 21.2% of all admissions for COVID-19 and 24.0% of ICU admissions. Compared with influenza, patients with COVID-19 had significantly greater in-hospital mortality (unadjusted 19.9% v. 6.1%, adjusted relative risk [RR] 3.46, 95% confidence interval [CI] 2.56–4.68), ICU use (unadjusted 26.4% v. 18.0%, adjusted RR 1.50, 95% CI 1.25–1.80) and hospital length of stay (unadjusted median 8.7 d v. 4.8 d, adjusted rate ratio 1.45, 95% CI 1.25–1.69). Thirty-day readmission was not significantly different (unadjusted 9.3% v. 9.6%, adjusted RR 0.98, 95% CI 0.70–1.39). Three points-based risk scores for predicting in-hospital mortality showed good discrimination (area under the receiver operating characteristic curve [AUC] ranging from 0.72 to 0.81) and calibration.INTERPRETATION:During the first wave of the pandemic, admission to hospital for COVID-19 was associated with significantly greater mortality, ICU use and hospital length of stay than influenza. Simple risk scores can predict in-hospital mortality in patients with COVID-19 with good accuracy.

International studies report that patients admitted to hospital with coronavirus disease 2019 (COVID-19) have high rates of critical illness and mortality.^1–5 Two small Canadian case series have described care for critically ill patients with COVID-19 and found mortality rates of up to 25%.^6,7 However, outcomes of patients admitted to hospital for COVID-19 in Canada are not well described, particularly outside of intensive care units (ICUs). Case fatality rates for COVID-19 vary dramatically worldwide,⁸ and outcomes of patients admitted to hospital for COVID-19 in Canada may differ from other countries because of differences in populations, public health and health care systems.Seasonal influenza is a useful comparator for COVID-19^9–11 as it is another respiratory virus, familiar to the general public, with high rates of morbidity and mortality. The purpose of this study was to describe patient characteristics, resource use, clinical care and outcomes for patients admitted to hospital with COVID-19 in Ontario, Canada, using influenza as a comparator. We also validated the performance of various prognostic risk scores for in-hospital mortality among patients with COVID-19.