Flavonoids as Potential Antiviral Agents for Porcine Viruses

Discovery of Flavonol derivatives as porcine reproductive and respiratory syndrome virus inhibitors

Porcine reproductive and respiratory syndrome virus (PRRSV) causes serious threat to the global pig industry, and there was still no efficient treatment for porcine reproductive and respiratory syndrome (PRRS). Flavonol compounds were reported to show antiviral activity against a series of different virus. In this study, we designed a series of flavonol derivatives as promising lead structure for PRRSV inhibitors. A flavonol derivative database with diverse structures was first generated, and their anti-PRRSV activity were test. Among these compounds, compound 4s showed promising anti-PRRSV activity with EC50 values of 0.45 μM. In addition, it exhibited low cytotoxicity with CC50 higher than 100 μM. We also found that compound 4s inhibited PRRSV might be by repressing the activity of nsp4 protease. Molecular modeling study revealed that compound 4s binding to nsp4 mainly relies on a salt bridge and hydrophobic interaction. Our results might provide a new way for the development of PRRSV inhibitors.

Unveiling the Biological Activities, Pharmacological Potential, and Health Benefits of Sorbifolin: A Comprehensive Review

Bioactive phytochemicals act as important factors with preventive and therapeutic potential in the pathogenesis of several disorders, often related to oxidative stress. Many dietary plant secondary metabolites could lower these conditions. Sorbifolin is one of these metabolites. This work is the first review of sorbifolin, a flavone detected in various plant matrices as a major compound. The present study discussed the natural sources, extraction, purification, quantification, and assessment of the biological activities of sorbifolin. Several databases including Google Scholar, Web of Sciences, and Science-Direct were consulted for relevant English articles related to sorbifolin, the phytochemical profiles of several medicinal plants containing this compound, and its biological activities, such as antioxidant, anticancer, antimicrobial, anti-inflammatory, and antidiabetic. The positive in vitro and in silico outcomes reported in the literature should be followed by additional in vivo and clinical investigations to further research the mechanisms of action, pharmacokinetic/pharmacodynamic activities, toxicological effects, pharmacological properties, and therapeutic potential of sorbifolin.

Exploring the Effect of Active Components in Oil Tree Peony Seed Meal on Swine Disease Resistance and its Potential Mechanisms Based on Network Pharmacology and Molecular Docking

This study aims to explore the feasibility of using network pharmacology and molecular docking technology to predict the effects of active components from oil tree peony seed meal (PSM) on swine diseases. Ten active components of PSM were screened Screening through literature search and network pharmacology standards, including Betulinic acid, Quercetin, Kaempferol, Luteolin, Isorhamnetin, Hydroxygenkwanin, Hederagenin, Benzoyl Paeoniflorin, Albiflorin, Paeoniflorin. Ten types of swine diseases were selected, including African Swine Fever, Aftosa, Swine Vesicular Disease, Transmissible Gastroenteritis, Swine Streptococcal Infection, Blue Aural Disease, Swine Infectious Atrophic Rhinitis, Swine Influenza, Swine Erysipelas, Swine Epidemic Encephalitis. The results showed that the average number of cross genes between the potential target genes of PSM active components and each swine disease target gene accounted for 7.64 % of the total number of swine disease target genes. The GO enrichment analyses showed that putative targets exist in endosomes, lysosomes, cell membranes, nerves, growth factor activity, receptor tyrosine kinase binding, enzyme binding, growth factor binding, transcription coactivator binding, oxidoreductase activity, prostaglandin E receptor activity and insulin receptor substrate binding. The KEGG enrichment analysis results showed that these putative genes were involved in various cancer progression pathways, signaling pathways, and hormone regulatory pathways. A total of 8 core targets were obtained through protein-protein interaction networks analysis, including Protein Kinase CAMP-Activated Catalytic Subunit Alpha (PRKACA), Non-Receptor Tyrosine Kinase (SRC), Mitogen-Activated Protein Kinase 1 (MAPK1), E1A Binding Protein P300 (EP300), Hypoxia Inducible Factor 1 Subunit Alpha (HIF1A), Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Beta (PIK3CB), C-X-C chemokine receptor type 4 (CXCR4) and Estrogen Receptor 2 (ESR2). The HIF-1 signaling pathway was found to be associated with all 10 selected swine diseases. The PD-L1 expression, and PD-1 checkpoint pathway in cancer, and thyroid hormone signaling pathway were not only enriches the core target with a quantity of 7, but also associated with 9 Swine diseases. In addition, the molecular docking results indicate that the core ingredients have strong affinity with hub genes. The research suggests that the active components of PSM may intervene in swine diseases through multiple components, targets, and pathways.

Association of flavonoid intake with coronary artery disease risk in the older population based on the National Health and Nutrition Examination Survey

We investigated the association between flavonoid intake and coronary artery disease (CAD) risk in older adults. Data were extracted from the National Health and Nutrition Examination Survey (age ≥ 70 years; 2007-2010 and 2017-2018; n = 2 417). The total flavonoid and flavonoid subclass intake was calculated using validated food frequency questionnaires. The association between flavonoid intake and CAD risk was examined using generalized linear models with restricted cubic spline models. After multivariate adjustment, anthocyanin intake was positively associated with CAD risk; no significant associations were observed between other flavonoid subcategories and endpoint outcomes. Anthocyanins exhibited a non-linear association with CAD risk, and threshold effect analysis showed an inflection point of 15.8 mg/day for anthocyanins. Per unit increase in anthocyanins, the odds of CAD on the left of the inflection point decreased by 2%, while the odds on the right increased by 35.8%. Excessive flavonoid intake may increase CAD risk in the older population.

Water Extract of Portulaca Oleracea Inhibits PEDV Infection-Induced Pyrolysis by Caspase-1/GSDMD

Porcine epidemic diarrhea virus (PEDV) belongs to the coronavirus family and the coronavirus genus, causing contact enteric infection in pigs. It is one of the most serious diseases that threatens the pig industry. However, there is currently no specific drug to prevent and treat the disease, indicating that we need to be vigilant about the spread of the disease and the development of anti-PEDV drugs. The dried aerial parts of the plant Portulaca oleracea in the family Portulacaceous, whose decoction can be used to treat acute enteritis, dysentery, diarrhea, and other diseases. This study explored the potential mechanism of water extract of Portulaca oleracea (WEPO) in PEDV-induced pyroptosis in Vero cells. PEDV decreased the viability of Vero cells in a dose- and time-dependent manner, causing cell damage, upregulating the level of intracellular Nlrp3, and inhibiting the level of Gasdermin D (GSDMD) and the activation of Caspase-1. WEPO can inhibit PEDV-induced pyroptosis, reduce the elevation of inflammatory factors caused by infection, and exhibit a dose-dependent effect. Knockdown of Caspase-1 and GSDMD separately can induce the production of the inflammatory factor IL-1β to significantly decrease and increase, respectively. These results suggest that WEPO can inhibit cell pyroptosis caused by PEDV and that the Caspase-1 and GSDMD pathways play an important role in this process.

Polygalic acid inhibits african swine fever virus polymerase activity: findings from machine learning and in vitro testing

African swine fever virus (ASFV), an extremely contagious virus with high mortality rates, causes severe hemorrhagic viral disease in both domestic and wild pigs. Fortunately, ASFV cannot be transmitted from pigs to humans. However, ongoing ASFV outbreaks could have severe economic consequences for global food security. Although ASFV was discovered several years ago, no vaccines or treatments are commercially available yet; therefore, the identification of new anti-ASFV drugs is urgently warranted. Using molecular docking and machine learning, we have previously identified pentagastrin, cangrelor, and fostamatinib as potential antiviral drugs against ASFV. Here, using machine learning combined with docking simulations, we identified natural products with a high affinity for AsfvPolX proteins. We selected five natural products (NPs) that are located close in chemical space to the six known natural flavonoids that possess anti-ASFV activity. Polygalic acid markedly reduced AsfvPolX polymerase activity in a dose-dependent manner. We propose an efficient protocol for identifying NPs as potential antiviral drugs by identifying chemical spaces containing high-affinity binders against ASFV in NP databases.

Structure-based drug design, molecular dynamics simulation, ADMET, and quantum chemical studies of some thiazolinones targeting influenza neuraminidase

The genetic mutability of the influenza virus leads to the existence of drug-resistant strains which is dangerous, particularly with the lingering coronavirus disease (COVID-19). This necessitated the need for the search and discovery of more potential anti-influenza agents to avert future outbreaks. In furtherance of our previous in-silico studies on 5-benzyl-4-thiazolinones as anti-influenza neuraminidase (NA) inhibitors, molecule 11 was selected as the template scaffold for the structure-based drug design due to its good binding, pharmacokinetic profiling, and better NA inhibitory activity. As such, eighteen (18) new molecules (11a-r) were designed with better MolDock scores as compared with the template scaffold and the zanamivir reference drug. However, the dynamic stability of molecule 11a in the binding cavity of the NA target (3TI5) showed water-mediated hydrogen and hydrophobic bondings with the active residues such as Arg118, Ile149, Arg152, Ile222, Trp403, and Ile427 after the MD simulation for 100 ns. The drug-likeness and ADMET assessment of all designed molecules predicted non-violation of the stipulated thresholds of Lipinski's rule and good pharmacokinetic properties respectively. In addition, the quantum chemical calculations also suggested the significant chemical reactivity of molecules with their smaller band energy gap, high electrophilicity, high softness, and low hardness. The results obtained in this study proposed a reliable in-silico viewpoint for anti-influenza drug discovery and development.Communicated by Ramaswamy H. Sarma.

Dihydromyricetin Inhibits Pseudorabies Virus Multiplication In Vitro by Regulating NF-κB Signaling Pathway and Apoptosis

Pseudorabies virus (PRV) infections have caused huge economic losses to the breeding industry worldwide, especially pig husbandry. PRV could threaten human health as an easily ignored zoonotic pathogen. The emergence of new mutants significantly reduced the protective effect of vaccination, indicating an urgent need to develop specific therapeutic drugs for PRV infection. In this study, we found that dihydromyricetin (DMY) could dose-dependently restrain PRV infection in vitro with an IC50 of 161.34 μM; the inhibition rate of DMY at a concentration of 500 μM was 92.16 %. Moreover, the mode of action showed that DMY directly inactivated PRV virion and inhibited viral adsorption and cellular replication. DMY treatment could improve PRV-induced abnormal changes of the NF-κB signaling pathway and excessive inflammatory response through regulation of the contents of IκBα and p-P65/P65 and the transcriptional levels of cytokines (TNF-α, IL-1β and IL-6). Furthermore, DMY promoted the apoptosis of PRV-infected cells through the regulation of the expressions of Bax and Bcl-xl and the transcriptional levels of Caspase-3, Bax, Bcl-2 and Bcl-xl, thereby limiting the production of progeny virus. These findings indicated that DMY could be a candidate drug for the treatment of PRV infection.

Comprehensive Review of Recent Advances in Chiral A-Ring Flavonoid Containing Compounds: Structure, Bioactivities, and Synthesis

Flavonoids are a group of natural polyphenolic substances that are abundant in vegetables, fruits, grains, and tea. Chiral A-ring-containing flavonoids are an important group of natural flavonoid derivatives applicable in a wide range of biological activities such as, cytotoxic, anti-inflammatory, anti-microbial, antioxidant, and enzyme inhibition. The desirable development of chiral A-ring-containing flavonoids by isolation, semi-synthesis or total synthesis in a short duration proves their great value in medicinal chemistry research. In this review, the research progress of chiral A-ring-containing flavonoids, including isolation and extraction, structural identification, pharmacological activities, and synthetic methods, is comprehensively and systematically summarized. Furthermore, we provide suggestions for future research on the synthesis and biomedical applications of flavonoids.