Pentagalloylglucose Inhibits the Replication of Rabies Virus via Mediation of the miR-455/SOCS3/STAT3/IL-6 Pathway

Development of Human Monoclonal Antibodies With Broad Reactivity for Rabies Postexposure Prophylaxis

Rabies is an acute lethal disease causing by the neurotropic virus rabies virus (RABV). Rabies immune globulin (RIG) as an indispensable component of rabies postexposure prophylaxis (PEP) always faces with great challenges in terms of costs, stability and safety. Our objective is to develop a novel and potential fully human monoclonal antibodies (mAbs) cocktail for the improvement of rabies PEP. The neutralizing fully human mAbs were screened by using fully humanized antibody mice (CAMouseHG). Then, two mAbs 26-12 G and 5-7 G were selected with potential neutralizing activity to RABV by using fluorescent antibody virus neutralization test (FAVN), which specifically bind to antigenic sites I and III of RABV-glycoprotein (RABV-G), the key amino acid residues were further identified in position 336, 337 of 5-7 G and 226, 227, 228 of 26-12 G by using cross-linking and mass-spectrometry. Both mAbs are highly conserved across 8 RABV strains (distributing in 3 lineages: Asian, Cosmopolitan and Arctic-related) and 1 IRKV strain, and showed high neutralizing potential. Moreover, the in vivo experiment demonstrated that our cocktail can protect Kunming mice from a lethal RABV challenge. Collectively, we generate two noncompeting fully human mAbs (26-12 G, 5-7 G) and obtained cocktail CAM001 with their mixture. The high-potency and broad-spectrum neutralization of the cocktail supports its utility in human rabies PEP as an efficacious and affordable alternative to RIG products, particularly in endemic areas.

BioKA: a curated and integrated biomarker knowledgebase for animals

Biomarkers play an important role in various area such as personalized medicine, drug development, clinical care, and molecule breeding. However, existing animals' biomarker resources predominantly focus on human diseases, leaving a significant gap in non-human animal disease understanding and breeding research. To address this limitation, we present BioKA (Biomarker Knowledgebase for Animals, https://ngdc.cncb.ac.cn/bioka), a curated and integrated knowledgebase encompassing multiple animal species, diseases/traits, and annotated resources. Currently, BioKA houses 16 296 biomarkers associated with 951 mapped diseases/traits across 31 species from 4747 references, including 11 925 gene/protein biomarkers, 1784 miRNA biomarkers, 1043 mutation biomarkers, 773 metabolic biomarkers, 357 circRNA biomarkers and 127 lncRNA biomarkers. Furthermore, BioKA integrates various annotations such as GOs, protein structures, protein-protein interaction networks, miRNA targets and so on, and constructs an interactive knowledge network of biomarkers including circRNA-miRNA-mRNA associations, lncRNA-miRNA associations and protein-protein associations, which is convenient for efficient data exploration. Moreover, BioKA provides detailed information on 308 breeds/strains of 13 species, and homologous annotations for 8784 biomarkers across 16 species, and offers three online application tools. The comprehensive knowledge provided by BioKA not only advances human disease research but also contributes to a deeper understanding of animal diseases and supports livestock breeding.

MicroRNA expression profile of human umbilical vein endothelial cells in response to coxsackievirus A10 infection reveals a potential role of miR-143-3p in maintaining the integrity of the blood-brain barrier

Coxsackievirus A10 (CV-A10) has been one of the main etiologies of hand, foot, and mouth disease (HFMD) epidemics in recent years and can cause mild to severe illness and even death. Most of these severe and fatal cases were closely associated with neurological impairments, but the potential mechanism of neuropathological injury triggered by CV-A10 infection has not been elucidated. MicroRNAs (miRNAs), implicated in the regulation of gene expression in a post-transcriptional manner, play a vital role in the pathogenesis of various central nervous system (CNS) diseases; therefore, they serve as diagnostic biomarkers and are emerging as novel therapeutic targets for CNS injuries. To gain insights into the CV-A10-induced regulation of host miRNA-processing machinery, we employed high-throughput sequencing to identify differentially expressed miRNAs in CV-A10-infected human umbilical vein endothelial cells (HUVECs) and further analyzed the potential functions of these miRNAs during CV-A10 infection. The results showed that CV-A10 infection could induce 189 and 302 significantly differentially expressed miRNAs in HUVECs at 24 and 72 hpi, respectively, compared with the uninfected control. Moreover, the expression of four selected miRNAs and their relevant mRNAs was determined to verify the sequencing data by quantitative reverse transcription-polymerase chain reaction (RT-qPCR) methods. After that, gene target prediction and functional annotation revealed that the targets of these dysregulated miRNAs were mostly enriched in cell proliferation, signal transduction, cAMP signalling pathway, cellular response to interleukin-6, ventral spinal cord interneuron differentiation, negative regulation of glial cell differentiation, neuron migration, positive regulation of neuron projection development, etc., which were primarily involved in the processes of basic physiology, host immunity, and neurological impairments and further reflected vital regulatory roles of miRNA in viral pathogenicity. Finally, the construction of a miRNA-regulated network also suggested that the complex regulatory mechanisms mediated by miRNAs might be involved in viral pathogenesis and virus-host interactions during CV-A10 infection. Furthermore, among these dysregulated miRNAs, miR-143-3p was demonstrated to be involved in the maintenance of blood-brain barrier (BBB) integrity.

Pentagalloyl Glucose: A Review of Anticancer Properties, Molecular Targets, Mechanisms of Action, Pharmacokinetics, and Safety Profile

Pentagalloyl glucose (PGG) is a natural hydrolyzable gallotannin abundant in various plants and herbs. It has a broad range of biological activities, specifically anticancer activities, and numerous molecular targets. Despite multiple studies available on the pharmacological action of PGG, the molecular mechanisms underlying the anticancer effects of PGG are unclear. Here, we have critically reviewed the natural sources of PGG, its anticancer properties, and underlying mechanisms of action. We found that multiple natural sources of PGG are available, and the existing production technology is sufficient to produce large quantities of the required product. Three plants (or their parts) with maximum PGG content were Rhus chinensis Mill, Bouea macrophylla seed, and Mangifera indica kernel. PGG acts on multiple molecular targets and signaling pathways associated with the hallmarks of cancer to inhibit growth, angiogenesis, and metastasis of several cancers. Moreover, PGG can enhance the efficacy of chemotherapy and radiotherapy by modulating various cancer-associated pathways. Therefore, PGG can be used for treating different human cancers; nevertheless, the data on the pharmacokinetics and safety profile of PGG are limited, and further studies are essential to define the clinical use of PGG in cancer therapies.

Deoxynivalenol Mycotoxin Inhibits Rabies Virus Replication In Vitro

Rabies is a highly fatal disease, and it is vital to find effective ways to manage and control infection. There is a need for new effective antiviral drugs that are particularly effective treatments for rabies. Deoxynivalenol (DON) is known mainly for its toxicity, but at the molecular level, it can inhibit RNA and DNA replication, and there is increasing evidence that different doses of DON have a positive effect on inhibiting virus replication. Based on this, we evaluated the effect of DON on inhibiting the rabies virus in vitro. The inhibitory effect of DON on rabies virus activity was dose- and time-dependent, and 0.25 μg/mL of DON could inhibit 99% of rabies virus activity within 24 h. Furthermore, DON could inhibit the adsorption, entry, replication, and release of rabies virus but could not inactivate the virus. The inhibitory effect of DON on rabies virus may be achieved by promoting apoptosis. Our study provides a new perspective for the study of anti-rabies virus and expands the direction of action of mycotoxins.

In vitro metabolic biomodulation of irinotecan to increase potency and reduce dose-limiting toxicity by inhibition of SN-38 glucuronide formation

OBJECTIVES

Colorectal cancer continues to have one of the highest incidents of occurrence with a rising rate of diagnosis among people under the age of 50. Chemotherapy with irinotecan results in severe gastrointestinal dose-limiting toxicity that is caused by the glucuronidated form of the active metabolite (SN-38G). This study evaluates herbal compounds and analogs to biomodulate the metabolism of IR to decrease dose-limiting toxicity while increasing the amount of the active metabolite.

METHODS

In vitro metabolism using human liver microsomes was conducted with white willow bark (WWB) extract, select specific components of WWB, and analogues to evaluate biomodulation of the IR metabolism. Samples were analyzed using liquid chromatography-tandem mass spectrometry to measure metabolites between reactions with and without herbals components.

RESULTS

WWB showed an optimal decrease (>80%) in SN-38G and a corresponding increase in SN-38 levels (128%) at a concentration of near 200 μg/mL. Tannic acid produced a 75% decrease in SN-38G with a 130% increase in SN-38 at 10 μg/mL, whereas the treatment with beta-pentagalloyl glucose and various analogues decreased SN-38G by 70% and increased SN-38 by 20% at 10 μg/mL.

CONCLUSIONS

These results suggest naturally occurring compounds from WWB may have the potential to increase potency by increasing the conversion of IR to SN-38 and decrease dose-limiting toxicity of IR chemotherapy by reducing glucuronidation of SN-38.

Penta-O-Galloyl-β-D-Glucose in Pistacia integerrima Targets AMPK-ULK1 and ERK/STAT3 Signaling Axes to Induce ROS-Independent Autophagic Cell Death in Human Lung Cancer Cells

Natural molecules have promising perspectives as adjuvants to chemotherapies against cancer. Pistacia chinensis subsp. Integerrima (hereafter, Pistacia integerrima) traditionally known for medicinal values in respiratory disorders was tested for anti-lung cancer properties. The extract prepared from Pistacia integerrima (PI) selectively impaired the viability of lung cancer cells, A549 and NCI-H460, compared to non-cancer cells. At non-lethal concentrations, PI mitigated colony-forming, spheroid formations and metastatic properties of lung cancer cells. As a step toward identifying the phytomolecule that is imparting the anti-lung cancer properties in PI, we subjected the extract to extensive characterization through UPLC/QToF-MS and further validated the findings with UHPLC. The gallotannin, penta-O-galloyl-β-D-glucose (PGG), among others, was identified through UPLC/QToF-MS. PGG exhibits potential chemopreventive effects against various cancer types. However, a defined mechanism of action of PGG in restricting lung cancer progression is still unexplored. Bioactivity-guided column fractionations enabled the determination of PGG as the major phytochemical that governed PI-mediated AMPK-ULK1-dependent autophagy and apoptosis, albeit independent of intracellular ROS activation. Interestingly, the autophagy flux when inhibited restored the cell viability even in the presence of PI. The study further delineated that PI and PGG activated ERK and inhibited STAT3 to trigger apoptosis through caspase-3 and PARP 1 pathways. Collectively, the finding demonstrates that plant extract, PGG, in the PI extract effectively combats lung cancer progression through autophagic cell death by altering ERK/AMPK-ULK1/STAT3 signaling axes. The study proposes PGG as a potential AMPK activator and STAT3 inhibitor that can be exploited further in developing adjuvant chemotherapeutics against lung cancer.

Natural Polyphenols, 1,2,3,4,6-O-Pentagalloyglucose and Proanthocyanidins, as Broad-Spectrum Anticoronaviral Inhibitors Targeting Mpro and RdRp of SARS-CoV-2

The natural plant dietary polyphenols 1,2,3,4,6-O-Pentagalloylglucose (PGG) and proanthocyanidin (PAC) have potent antioxidant activity and a variety of pharmacological activities, including antiviral activity. In this study, we examined the inhibitory effect of PGG and PAC on SARS-CoV-2 virus infection, and elucidated its mode of action. PGG and PAC have dose-dependent inhibitory activity against SARS-CoV-2 infection in Vero cells. PGG has a lower IC₅₀ (15.02 ± 0.75 μM) than PAC (25.90 ± 0.81 μM), suggesting that PGG has better inhibitory activity against SARS-CoV-2 than PAC. The PGG and PAC inhibit similar Mpro activities in a protease activity assay, with IC₅₀ values of 25–26 μM. The effects of PGG and PAC on the activity of the other essential SARS-CoV-2 viral protein, RdRp, were analyzed using a cell-based activity assay system. The activity of RdRp is inhibited by PGG and PAC, and PGG has a lower IC₅₀ (5.098 ± 1.089 μM) than PAC (21.022 ± 1.202 μM), which is consistent with their inhibitory capacity of SARS-CoV-2 infection. PGG and PAC also inhibit infection by SARS-CoV and MERS-CoV. These data indicate that PGG and PAC may be candidate broad-spectrum anticoronaviral therapeutic agents, simultaneously targeting the Mpro and RdRp proteins of SARS-CoV-2.

Polyphenols and their potential role to fight viral diseases: An overview

Fruits, vegetables, spices, and herbs are a potential source of phenolic acids and polyphenols. These compounds are known as natural by-products or secondary metabolites of plants, which are present in the daily diet and provide important benefits to the human body such as antioxidant, anti-inflammatory, anticancer, anti-allergic, antihypertensive and antiviral properties, among others. Plentiful evidence has been provided on the great potential of polyphenols against different viruses that cause widespread health problems. As a result, this review focuses on the potential antiviral properties of some polyphenols and their action mechanism against various types of viruses such as coronaviruses, influenza, herpes simplex, dengue fever, and rotavirus, among others. Also, it is important to highlight the relationship between antiviral and antioxidant activities that can contribute to the protection of cells and tissues of the human body. The wide variety of action mechanisms of antiviral agents, such as polyphenols, against viral infections could be applied as a treatment or prevention strategy; but at the same time, antiviral polyphenols could be used to produce natural antiviral drugs. A recent example of an antiviral polyphenol application deals with the use of hesperidin extracted from Citrus sinensis. The action mechanism of hesperidin relies on its binding to the key entry or spike protein of SARS-CoV-2. Finally, the extraction, purification and recovery of polyphenols with potential antiviral activity, which are essential for virus replication and infection without side-effects, have been critically reviewed.

Expression Profiling and Bioinformatics Analysis of CircRNA in Mice Brain Infected with Rabies Virus

Rabies virus (RABV) induces acute, fatal encephalitis in mammals including humans. The circRNAs are important in virus infection process, but whether circRNAs regulated RABV infection remains largely unknown. Here, mice brain with or without the RABV CVS-11 strain were subjected to RNA sequencing and a total of 30,985 circRNAs were obtained. Among these, 9021 candidates were shared in both groups, and 14,610 and 7354 circRNAs were expressed specifically to the control and experimental groups, indicating that certain circRNAs were specifically inhibited or induced on RABV infection. The circRNAs mainly derived from coding exons. In total, 636 circRNAs were differentially expressed in RABV infection, of which 426 significantly upregulated and 210 significantly downregulated (p < 0.05 and fold change ≥2). The expression of randomly selected 6 upregulated and 6 downregulated circRNAs was tested by RT-qPCR, and the expression trend of the 11 out of 12 circRNAs was consistent in RT- qPCR and RNA-seq analysis. Rnase R-resistant assay and Sanger sequencing were conducted to verify the circularity of circRNAs. GO analysis demonstrated that source genes of all differentially regulated circRNAs were mainly related to cell plasticity and synapse function. Both KEGG and GSEA analysis revealed that these source genes were engaged in the cGMP–PKG and MAPK signaling pathway, and HTLV-I infection. Also, pathways related to glucose metabolism and synaptic functions were enriched in KEGG analysis. The circRNA–miRNA–mRNA network was built with 25 of 636 differentially expressed circRNAs, 264 mRNAs involved in RABV infection, and 29 miRNAs. Several miRNAs and many mRNAs in the network were reported to be related to viral infection and the immune response, suggesting that circRNAs could regulate RABV infection via interacting with miRNAs and mRNAs. Taken together, this study first characterized the transcriptomic pattern of circRNAs, and signaling pathways and function that circRNAs are involved in, which may indicate directions for further research to understand mechanisms of RABV pathogenesis.

miR-455-5p regulates atrial fibrillation by targeting suppressor of cytokines signaling 3

Atrial fibrillation (AF) is a condition that heart beats quaveringly or irregularly, which causes blood clots, heart failure, stroke, and other heart-related complications. Therefore, early diagnosis and timely preventions are necessary for AF treatment. Compelling evidence indicated that microRNAs (miRNAs) become emerging biomarkers of AF; thus, we aimed to investigate the possibility of miR-455-5p as an AF marker to provide a new strategy for early diagnosis of AF. A minipump containing angiotensin II was implanted into mice to induce AF, and adeno-associated virus (AAV) carrying anti-miR-negative control (NC) or anti-miR-455-5p was injected into the pericardial space of mice respectively. Next, myocytes isolated from wild-type newborn mice were stimulated with angiotensin II and anti-miR-NC or anti-miR-455-5p mimic. The results showed that the expression of miR-455-5p was positively correlated with the severity of AF, and miR-455-5p mimic accelerated the progression of AF by directly binding to its target gene suppressor of cytokines signaling 3 (SOCS3), leading to the activation of signal transducer and activator of transcription 3 (STAT3) signaling pathway. On the contrary, inhibition of miR-455-5p expression effectively ameliorated AF. In conclusion, miR-455-5p might serve as a biomarker of AF.

High Capability of Pentagalloylglucose (PGG) in Inhibiting Multiple Types of Membrane Ionic Currents

Pentagalloyglucose (PGG, penta-O-galloyl-β-d-glucose; 1,2,3,4,6-pentagalloyl glucose), a pentagallic acid ester of glucose, is recognized to possess anti-bacterial, anti-oxidative and anti-neoplastic activities. However, to what extent PGG or other polyphenolic compounds can perturb the magnitude and/or gating of different types of plasmalemmal ionic currents remains largely uncertain. In pituitary tumor (GH₃) cells, we found out that PGG was effective at suppressing the density of delayed-rectifier K⁺ current (I_K(DR)) concentration-dependently. The addition of PGG could suppress the density of proton-activated Cl⁻ current (I_PAC) observed in GH₃ cells. The IC₅₀ value required for the inhibitory action of PGG on I_K(DR) or I_PAC observed in GH₃ cells was estimated to be 3.6 or 12.2 μM, respectively, while PGG (10 μM) mildly inhibited the density of the erg-mediated K⁺ current or voltage-gated Na⁺ current. The presence of neither chlorotoxin, hesperetin, kaempferol, morin nor iberiotoxin had any effects on I_PAC density, whereas hydroxychloroquine or 4-[(2-butyl-6,7-dichloro-2-cyclopentyl-2,3-dihydro-1-oxo-1H-inden-5yl)oxy] butanoic acid suppressed current density effectively. The application of PGG also led to a decrease in the area of voltage-dependent hysteresis of I_PAC elicited by long-lasting isosceles-triangular ramp voltage command, suggesting that hysteretic strength was lessened in its presence. In human cardiac myocytes, the exposure to PGG also resulted in a reduction of ramp-induced I_K(DR) density. Taken literally, PGG-perturbed adjustment of ionic currents could be direct and appears to be independent of its anti-oxidative property.

The Dynamic Interface of Viruses with STATs

Viruses commonly antagonize the antiviral type I interferon response by targeting signal transducer and activator of transcription 1 (STAT1) and STAT2, key mediators of interferon signaling. Other STAT family members mediate signaling by diverse cytokines important to infection, but their relationship with viruses is more complex. Importantly, virus-STAT interaction can be antagonistic or stimulatory depending on diverse viral and cellular factors. While STAT antagonism can suppress immune pathways, many viruses promote activation of specific STATs to support viral gene expression and/or produce cellular conditions conducive to infection. It is also becoming increasingly clear that viruses can hijack noncanonical STAT functions to benefit infection. For a number of viruses, STAT function is dynamically modulated through infection as requirements for replication change. Given the critical role of STATs in infection by diverse viruses, the virus-STAT interface is an attractive target for the development of antivirals and live-attenuated viral vaccines. Here, we review current understanding of the complex and dynamic virus-STAT interface and discuss how this relationship might be harnessed for medical applications.

Lyssavirus P-protein selectively targets STAT3-STAT1 heterodimers to modulate cytokine signalling

Many viruses target signal transducer and activator of transcription (STAT) 1 to antagonise antiviral interferon signalling, but targeting of STAT3, a pleiotropic molecule that mediates signalling by diverse cytokines, is poorly understood. Here, using lyssavirus infection, quantitative live cell imaging, innate immune signalling and protein interaction assays, and complementation/depletion of STAT expression, we show that STAT3 antagonism is conserved among P-proteins of diverse pathogenic lyssaviruses and correlates with pathogenesis. Importantly, P-protein targeting of STAT3 involves a highly selective mechanism whereby P-protein antagonises cytokine-activated STAT3-STAT1 heterodimers, but not STAT3 homodimers. RT-qPCR and reporter gene assays indicate that this results in specific modulation of interleukin-6-dependent pathways, effecting differential antagonism of target genes. These data provide novel insights into mechanisms by which viruses can modulate cellular function to support infection through discriminatory targeting of immune signalling complexes. The findings also highlight the potential application of selective interferon-antagonists as tools to delineate signalling by particular STAT complexes, significant not only to pathogen-host interactions but also cell physiology, development and cancer.

A Comprehensive Review of the Structure Elucidation of Tannins from Terminalia Linn

OBJECTIVES

Tannins with complex structures are important plant resources, which are abundant in the genus Terminalia. Various Terminalia species have been playing an important role in traditional medicine system. A systematic scoping review of Terminalia Linn. research literature for tannins was conducted to summarize the structures of tannins and analysis fragmentation pathway characteristics, which could provide references for the structural analysis of tannins from Terminalia Linn.

METHODS

After an update of the literature search up to September 2018, the terms of Terminalia in all publications were analyzed. Electronic searches were conducted in scifinder and PubMed, and the information from 197 articles in all with regard to the tannin structure study was extracted.

RESULTS

The compounds of 82 tannins from the genus Terminalia were reviewed. According to the structural differences, they can be divided into three categories, hydrolysable tannins, condensed tannins, and complex tannins, respectively. The fragmentation pathways of 46 identified tannins were analyzed, and the fragmentation rules of tannins were speculated according to different types.

CONCLUSION

This review has attracted attention to the active substances in this species such as the tannins summarized in further study. How to improve the extraction and purification technology of tannins from genus Terminalia is an urgent problem to be solved.