Honeysuckle aqueous extract and induced let-7a suppress dengue virus type 2 replication and pathogenesis

Toward a Categorization of Virus-ncRNA Interactions in the World of RNA to Disentangle the Tiny Secrets of Dengue Virus

In recent years, the function of noncoding RNAs (ncRNAs) as regulatory molecules of cell physiology has begun to be better understood. Advances in viral molecular biology have shown that host ncRNAs, cellular factors, and virus-derived ncRNAs and their interplay are strongly disturbed during viral infections. Nevertheless, the folding of RNA virus genomes has also been identified as a critical factor in regulating canonical and non-canonical functions. Due to the influence of host ncRNAs and the structure of RNA viral genomes, complex molecular and cellular processes in infections are modulated. We propose three main categories to organize the current information about RNA-RNA interactions in some well-known human viruses. The first category shows examples of host ncRNAs associated with the immune response triggered in viral infections. Even though miRNAs introduce a standpoint, they are briefly presented to keep researchers moving forward in uncovering other RNAs. The second category outlines interactions between virus-host ncRNAs, while the third describes how the structure of the RNA viral genome serves as a scaffold for processing virus-derived RNAs. Our grouping may provide a comprehensive framework to classify ncRNA-host-cell interactions for emerging viruses and diseases. In this sense, we introduced them to organize DENV-host-cell interactions.

The comparative analysis of Lonicerae Japonicae Flos and Lonicerae Flos: A systematical review

ETHNOPHARMACOLOGICAL RELEVANCE

Lonicerae Japonicae Flos (LJF) and Lonicerae Flos (LF) were once used as the same herb in China, but they were distinguished by Chinese Pharmacopoeia in 2005 in terms of their medicinal history, plant morphology, medicinal properties and chemical constituents. However, their functions, flavor, and meridian tropism are the same according to the Chinese pharmacopoeia 2020 edition, making researchers and customers confused.

AIM OF THE REVIEW

This review aimed to provide a comparative analysis of LJF and LF in order to provide a rational application in future research.

MATERIALS AND METHODS

The information was gathered from China National Knowledge Infrastructure (CNKI), SciFinder, Google Scholar, PubMed, Web of Science, and Chinese Masters and Doctoral Dissertations (all chosen articles were reviewed attentively from 1980.1 to 2023.8).

RESULTS

Till now, 507 chemical compounds have been isolated and identified in LJF, while 223 ones (79 overlapped compounds) are found in LF, including organic acids and derivatives, flavonoids, triterpenoids, iridoids, and essential oil components, etc. In addition, the pharmacological activities of LJF and LF, especially for their anti-influenza efficacy and mechanism, and their difference in terms of pharmacokinetic parameters, toxicology, and clinical applications were also summarized.

CONCLUSION

The current work offers comparative information between LJF and LF in terms of botany, traditional uses, phytochemistry, ethnopharmacology, pharmacokinetics, toxicology, and pharmacology, especially their anti-influenza activities. Despite the same clinical applications and similar chemical components in LJF and LF, differentiated components were still existed, resulting in differentiated pharmacological activities and pharmacokinetics parameters. Moreover, the research about anti-influenza mechanism and functional substances of LJF and LF is dramatically limited, restricting their clinical applications. In addition, few studies have investigated the metabolism feature of LF in vivo, which is one of the important bases for revealing the pharmacological mechanism of LF. At the same time, the toxicity of LJF and LF is not fully studied, and the toxic compounds of LJF and LF need to be screened out in order to standardize the drug use and improve their rational applications.

Engineered extracellular vesicles carrying let-7a-5p for alleviating inflammation in acute lung injury

BACKGROUND

Acute lung injury (ALI) is a life-threatening respiratory condition characterized by severe inflammation and lung tissue damage, frequently causing rapid respiratory failure and long-term complications. The microRNA let-7a-5p is involved in the progression of lung injury, inflammation, and fibrosis by regulating immune cell activation and cytokine production. This study aims to use an innovative cellular electroporation platform to generate extracellular vesicles (EVs) carring let-7a-5p (EV-let-7a-5p) derived from transfected Wharton's jelly-mesenchymal stem cells (WJ-MSCs) as a potential gene therapy for ALI.

METHODS

A cellular nanoporation (CNP) method was used to induce the production and release of EV-let-7a-5p from WJ-MSCs transfected with the relevant plasmid DNA. EV-let-7a-5p in the conditioned medium were isolated using a tangential flow filtration (TFF) system. EV characterization followed the minimal consensus guidelines outlined by the International Society for Extracellular Vesicles. We conducted a thorough set of therapeutic assessments, including the antifibrotic effects using a transforming growth factor beta (TGF-β)-induced cell model, the modulation effects on macrophage polarization, and the influence of EV-let-7a-5p in a rat model of hyperoxia-induced ALI.

RESULTS

The CNP platform significantly increased EV secretion from transfected WJ-MSCs, and the encapsulated let-7a-5p in engineered EVs was markedly higher than that in untreated WJ-MSCs. These EV-let-7a-5p did not influence cell proliferation and effectively mitigated the TGF-β-induced fibrotic phenotype by downregulating SMAD2/3 phosphorylation in LL29 cells. Furthermore, EV-let-7a-5p regulated M2-like macrophage activation in an inflammatory microenvironment and significantly induced interleukin (IL)-10 secretion, demonstrating their modulatory effect on inflammation. Administering EVs from untreated WJ-MSCs slightly improved lung function and increased let-7a-5p expression in plasma in the hyperoxia-induced ALI rat model. In comparison, EV-let-7a-5p significantly reduced macrophage infiltration and collagen deposition while increasing IL-10 expression, causing a substantial improvement in lung function.

CONCLUSION

This study reveals that the use of the CNP platform to stimulate and transfect WJ-MSCs could generate an abundance of let-7a-5p-enriched EVs, which underscores the therapeutic potential in countering inflammatory responses, fibrotic activation, and hyperoxia-induced lung injury. These results provide potential avenues for developing innovative therapeutic approaches for more effective interventions in ALI.

Experimental Dengue Virus Type 4 Infection Increases the Expression of MicroRNAs-15/16, Triggering a Caspase-Induced Apoptosis Pathway

The World Health Organization has estimated the annual occurrence of approximately 392 million dengue virus (DENV) infections in more than 100 countries where the virus is endemic, which represents a serious threat to humanity. DENV is a serologic group with four distinct serotypes (DENV-1, DENV-2, DENV-3, and DENV-4) belonging to the genus Flavivirus, in the family Flaviviridae. Dengue is the most widespread mosquito-borne disease in the world. The ~10.7 kb DENV genome encodes three structural proteins (capsid (C), pre-membrane (prM), and envelope (E)) and seven non-structural (NS) proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5). The NS1 protein is a membrane-associated dimer and a secreted, lipid-associated hexamer. Dimeric NS1 is found on membranes both in cellular compartments and cell surfaces. Secreted NS1 (sNS1) is often present in patient serum at very high levels, which correlates with severe dengue symptoms. This study was conducted to discover how the NS1 protein, microRNAs-15/16 (miRNAs-15/16), and apoptosis are related during DENV-4 infection in human liver cell lines. Huh 7.5 and HepG2 cells were infected with DENV-4, and miRNAs-15/16, viral load, NS1 protein, and caspases-3/7 were quantified after different durations of infection. This study demonstrated that miRNAs-15/16 were overexpressed during the infection of HepG2 and Huh 7.5 cells with DENV-4 and had a relationship with NS1 protein expression, viral load, and the activity of caspases-3/7, thus making these miRNAs potential injury markers during DENV infection in human hepatocytes.

Lonicera japonica Thunb. as a promising antibacterial agent for Bacillus cereus ATCC14579 based on network pharmacology, metabolomics, and in vitro experiments

Lonicera japonica Thunb. has attracted much attention for its treatment of bacterial and viral infectious diseases, while its active ingredients and potential mechanisms of action have not been fully elucidated. Here, we combined metabolomics, and network pharmacology to explore the molecular mechanism of Bacillus cereus ATCC14579 inhibition by Lonicera japonica Thunb. In vitro inhibition experiments showed that the Lonicera japonica Thunb.'s water extracts, ethanolic extract, luteolin, quercetin, and kaempferol strongly inhibited Bacillus cereus ATCC14579. In contrast, chlorogenic acid and macranthoidin B had no inhibitory effect on Bacillus cereus ATCC14579. Meanwhile, the minimum inhibitory concentrations of luteolin, quercetin, and kaempferol against Bacillus cereus ATCC14579 were 15.625 μg mL-1, 31.25 μg mL-1, and 15.625 μg mL-1. Based on the previous experimental basis, the metabolomic analysis showed the presence of 16 active ingredients in Lonicera japonica Thunb.'s water extracts and ethanol extracts, with differences in the luteolin, quercetin, and kaempferol contents between the water extracts and ethanol extracts. Network pharmacology studies indicated that fabZ, tig, glmU, secA, deoD, nagB, pgi, rpmB, recA, and upp were potential key targets. Active ingredients of Lonicera japonica Thunb. may exert their inhibitory effects by inhibiting ribosome assembly, the peptidoglycan biosynthesis process, and the phospholipid biosynthesis process of Bacillus cereus ATCC14579. An alkaline phosphatase activity assay, peptidoglycan concentration assay, and protein concentration assay showed that luteolin, quercetin, and kaempferol disrupted the Bacillus cereus ATCC14579 cell wall and cell membrane integrity. Transmission electron microscopy results showed significant changes in the morphology and ultrastructure of the cell wall and cell membrane of Bacillus cereus ATCC14579, further confirming the disruption of the cell wall and cell membrane integrity of Bacillus cereus ATCC14579 by luteolin, quercetin, and kaempferol. In conclusion, Lonicera japonica Thunb. can be used as a potential antibacterial agent for Bacillus cereus ATCC14579, which may exert its antibacterial activity by destroying the integrity of the cell wall and membrane.

Molecular Mechanisms of Antiviral Agents against Dengue Virus

Dengue is a major global health threat causing 390 million dengue infections and 25,000 deaths annually. The lack of efficacy of the licensed Dengvaxia vaccine and the absence of a clinically approved antiviral against dengue virus (DENV) drive the urgent demand for the development of novel anti-DENV therapeutics. Various antiviral agents have been developed and investigated for their anti-DENV activities. This review discusses the mechanisms of action employed by various antiviral agents against DENV. The development of host-directed antivirals targeting host receptors and direct-acting antivirals targeting DENV structural and non-structural proteins are reviewed. In addition, the development of antivirals that target different stages during post-infection such as viral replication, viral maturation, and viral assembly are reviewed. Antiviral agents designed based on these molecular mechanisms of action could lead to the discovery and development of novel anti-DENV therapeutics for the treatment of dengue infections. Evaluations of combinations of antiviral drugs with different mechanisms of action could also lead to the development of synergistic drug combinations for the treatment of dengue at any stage of the infection.

RNA Interference Approach Is a Good Strategy against SARS-CoV-2

COVID-19, caused by SARS-CoV-2, created a devastating outbreak worldwide and consequently became a global health concern. However, no verifiable, specifically targeted treatment has been devised for COVID-19. Several emerging vaccines have been used, but protection has not been satisfactory. The complex genetic composition and high mutation frequency of SARS-CoV-2 have caused an uncertain vaccine response. Small interfering RNA (siRNA)-based therapy is an efficient strategy to control various infectious diseases employing post-transcriptional gene silencing through the silencing of target complementary mRNA. Here, we designed two highly effective shRNAs targeting the conserved region of RNA-dependent RNA polymerase (RdRP) and spike proteins capable of significant SARS-CoV-2 replication suppression. The efficacy of this approach suggested that the rapid development of an shRNA-based therapeutic strategy might prove to be highly effective in treating COVID-19. However, it needs further clinical trials.

The effects and underlying mechanisms of medicine and food homologous flowers on the prevention and treatment of related diseases

The theory of medicine and food homology has a long history in China. Numerous traditional Chinese medicinal could be used as both medicine and food. Many flower medicinal materials also belong to the homology of medicine and food, such as Chrysanthemum morifolium, Lonicera japonica, Crocus sativus, and Lonicera macranthoides. They mainly contain flavonoids, organic acids, terpenoids, and other active ingredients, which have a variety of medicinal values, including anti-inflammatory, anti-tumor, and antioxidant. There are many formulations and functional foods containing these plants in Chinese medicine, which have a variety of nutritional and health effects on the human body. In this review, 10 widely used flowers were selected to review their pharmacological activities, prevention and treatment of related diseases and underlying mechanisms, and discussed the current limitations and future development prospects, hoping to provide references for the research on the development and utilization of natural medical flowers. PRACTICAL APPLICATIONS: The "homology of medicine and food" flowers have a wide range of uses and are of great research value. In this paper, we introduce 10 "homology of medicine and food" flowers. Their active ingredients, pharmacological activities, and treatments for related diseases are reviewed, and the limitations and development prospects of the "homology of medicine and food" flowers are discussed. It is hoped that this will contribute to the development of the food and pharmacological fields.

Therapeutic Potential of Medicinal Plants against Dengue Infection: A Mechanistic Viewpoint

Dengue is a tropical disease caused by the Dengue virus (DENV), a positive-sense, single stranded RNA virus of the family Flaviviridae, which is transmitted by Aedes mosquitoes. The occurrence of dengue has grown dramatically around the globe in recent decades, and it is rapidly becoming a global burden. Furthermore, all four DENV serotypes cocirculate and create a problematic hyperendemic situation. Characteristic symptoms range from being asymptomatic, dengue fever to life-threatening complications such as hemorrhagic fever and shock. Apart from the inherent virulence of the virus strain, a dysregulated host immune response makes the condition worse. Currently, there is no highly recommended vaccine or therapeutic agent against dengue. With the advent of virus strains resistant to antiviral agents, there is a constant need for new therapies to be developed. Since time immemorial, human civilization has utilized plants in traditional medicine to treat various diseases, including infectious viral diseases. With the advancement in molecular biology, cell biology techniques, and bioinformatics, recent studies have tried to provide scientific evidence and determine the mechanism of anti-dengue activity of various plant extracts and plant-derived agents. The current Review consolidates the studies on the last 20 years of in vitro and in vivo experiments on the ethnomedicinal plants used against the dengue virus. Several active phytoconstituents like quercetin, castanospermine, α-mangostin, schisandrin-A, hirsutin have been found to be promising to inhibition of all the four DENV serotypes. However, novel therapeutics need to be reassessed in relevant cells using high-throughput techniques. Further, in vivo dose optimization for the immunomodulatory and antiviral activity should be examined on a vast sample size. Such a Review should help take the knowledge forward, validate it, and use medicinal plants in different combinations targeting multiple stages of virus infection for more effective multipronged therapy against dengue infection.

The Influence of Host miRNA Binding to RNA Within RNA Viruses on Virus Multiplication

microRNAs (miRNAs), non-coding RNAs about 22 nt long, regulate the post-transcription expression of genes to influence many cellular processes. The expression of host miRNAs is affected by virus invasion, which also affects virus replication. Increasing evidence has demonstrated that miRNA influences RNA virus multiplication by binding directly to the RNA virus genome. Here, the knowledge relating to miRNAs’ relationships between host miRNAs and RNA viruses are discussed.

Lonicera caerulea (Haskap berries): a review of development traceability, functional value, product development status, future opportunities, and challenges

Lonicera caerulea is a honeysuckle plant with a long development history. It is defined as a "homology of medicine and food" fruit because it is rich in bioactive substances. By-products (such as pomace, leaves, stems, and flowers), which also have beneficial values, will be produced during processing. Nevertheless, the reuse of derivatives and the further development of new products of Lonicera caerulea are still a challenge. Firstly, this paper traced the development history of Lonicera caerulea and summarized its primary nutrients and bioactive substances, subsequently discussed the research progress and underlying molecular mechanisms of its functional properties, and introduced the application and potential of Lonicera caerulea in the fields of food, health products, cosmetics, medicine, and materials. Finally, this paper put forward the future research direction to promote the development of the Lonicera caerulea industry. To sum up, Lonicera caerulea, as a potential raw material, can be used to produce more functional products. Besides, more in-depth clinical trials are needed to clarify the specific molecular mechanism of the practical components of Lonicera caerulea and improve the rate of development and utilization.HighlightsThe original species of Lonicera caerulea subgroup had appeared on the earth as early as the end of the third century.Lonicera caerulea has been introduced into North America since the 18th century, but the introduction process has not ended until now.Lonicera caerulea widely exists in Eurasia and North America and it has excellent cold tolerance, early maturity and ornamental.The fruits, stems, leaves and flowers of Lonicera caerulea all have bioactive value, but the specific molecular mechanism and utilization need to be improved.Lonicera caerulea has been widely used in food, medicine, health products, cosmetics and materials, but there are still great challenges.

Honeysuckle (Lonicera japonica) and Huangqi (Astragalus membranaceus) Suppress SARS-CoV-2 Entry and COVID-19 Related Cytokine Storm in Vitro

COVID-19 is threatening human health worldwide but no effective treatment currently exists for this disease. Current therapeutic strategies focus on the inhibition of viral replication or using anti-inflammatory/immunomodulatory compounds to improve host immunity, but not both. Traditional Chinese medicine (TCM) compounds could be promising candidates due to their safety and minimal toxicity. In this study, we have developed a novel in silico bioinformatics workflow that integrates multiple databases to predict the use of honeysuckle (Lonicera japonica) and Huangqi (Astragalus membranaceus) as potential anti-SARS-CoV-2 agents. Using extracts from honeysuckle and Huangqi, these two herbs upregulated a group of microRNAs including let-7a, miR-148b, and miR-146a, which are critical to reduce the pathogenesis of SARS-CoV-2. Moreover, these herbs suppressed pro-inflammatory cytokines including IL-6 or TNF-α, which were both identified in the cytokine storm of acute respiratory distress syndrome, a major cause of COVID-19 death. Furthermore, both herbs partially inhibited the fusion of SARS-CoV-2 spike protein-transfected BHK-21 cells with the human lung cancer cell line Calu-3 that was expressing ACE2 receptors. These herbs inhibited SARS-CoV-2 M^pro activity, thereby alleviating viral entry as well as replication. In conclusion, our findings demonstrate that honeysuckle and Huangqi have the potential to be used as an inhibitor of SARS-CoV-2 virus entry that warrants further in vivo analysis and functional assessment of miRNAs to confirm their clinical importance. This fast-screening platform can also be applied to other drug discovery studies for other infectious diseases.

Traditional Knowledge to Contemporary Medication in the Treatment of Infectious Disease Dengue: A Review

Dengue has become a worldwide affliction despite incessant efforts to search for a cure for this long-lived disease. Optimistic consequences for dengue vaccine are implausible as the efficiency is tied to previous dengue virus (DENV) exposure and a very high cost is required for large-scale production of vaccine. Medicinal plants are idyllic substitutes to fight DENV infection since they constitute important components of traditional medicine and show antiviral properties, although the mechanism behind the action of bioactive compounds to obstruct viral replication is less explored and yet to be discovered. This review includes the existing traditional knowledge on how DENV infects and multiplies in the host cells, conscripting different medicinal plants that obtained bioactive compounds with anti-dengue properties, and the probable mechanism on how bioactive compounds modulate the host immune system during DENV infection. Moreover, different plant species having such bioactive compounds reported for anti-DENV efficiency should be validated scientifically via different in vitro and in vivo studies.

Reducing Acneiform Rash Induced by EGFR Inhibitors With Honeysuckle Therapy: A Prospective, Randomized, Controlled Study

Background: Epidermal growth factor receptor inhibitors (EGFRIs), including cetuximab, erlotinib, gefitinib and icotinib, have been proven to be effective in treating colorectal cancer or lung cancer. However, most of patients who receive EGFRIs treatment experience cutaneous toxicities, such as acneiform or papulopustular rashes, which affects quality of life and leads to discontinuation of cancer therapies. Honeysuckle is a traditional herb historically used to treat skin rash for thousands of years in Eastern Asia and showed proven safety in human.

Methods: To investigate whether honeysuckle therapy could control EGFRIs induced acneiform rashes, a total of 139 colorectal and lung cancer patients with EGFRIs treatments were recruited in a prospective study. Patients were randomized to 3 arms (Arm A: prophylactic treatment with honeysuckle before rash occurred; Arm B: symptomatic treatment with honeysuckle when rash occurred; Arm C: conventional treatment with minocycline and a topical solution when rash occurred). The incidences, severities and recovery time of acneiform rash were observed in each arm.

Results: Honeysuckle treatment reduced incidences of EGFRIs induced acneiform rash, which were 56.5, 68.1 and 71.7% in Arm A, B and C, respectively (p = 0.280). Severities of rash (CTCAE grade 2 and 3) were significantly lower in prophylactic honeysuckle treatment (Arm A) compared to conventional treatment (Arm C) (p = 0.027), which was 10–21%, respectively. Patients with honeysuckle treatment recovered more quickly from pruritus, the median time was 22, 36 and 58 days in Arm A, B and C, respectively (p = 0.016).

Conclusion: Honeysuckle was effective in reducing incidences and severities of EGFRIs induced acneiform rash, especially for prophylactic treatment.

MicroRNA let-7 and viral infections: focus on mechanisms of action

MicroRNAs (miRNAs) are fundamental post-transcriptional modulators of several critical cellular processes, a number of which are involved in host defense mechanisms. In particular, miRNA let-7 functions as an essential regulator of the function and differentiation of both innate and adaptive immune cells. Let-7 is involved in several human diseases, including cancer and viral infections. Several viral infections have found ways to dysregulate the expression of miRNAs. Extracellular vesicles (EV) are membrane-bound lipid structures released from many types of human cells that can transport proteins, lipids, mRNAs, and miRNAs, including let-7. After their release, EVs are taken up by the recipient cells and their contents released into the cytoplasm. Let-7-loaded EVs have been suggested to affect cellular pathways and biological targets in the recipient cells, and can modulate viral replication, the host antiviral response, and the action of cancer-related viruses. In the present review, we summarize the available knowledge concerning the expression of let-7 family members, functions, target genes, and mechanistic involvement in viral pathogenesis and host defense. This may provide insight into the development of new therapeutic strategies to manage viral infections.

The Aqueous Leaf Extract of M. Oleifera Inhibits PEDV Replication through Suppressing Oxidative Stress-Mediated Apoptosis

Simple Summary

The porcine epidemic diarrhea virus (PEDV), a porcine enteropathogenic coronavirus, can cause enormous economic losses in the swine industry. There is no effective commercial vaccine against PEDV infection. In this study, we found that an aqueous leaf extract of M. oleifera (MOE) exhibited antiviral activity in response to PEDV infection at the stage of PEDV replication instead of attachment or internalization. Mechanistically, MOE suppressed the oxidative stress and the expression of inflammatory cytokines induced by PEDV infection and upregulated the expression of anti-apoptotic proteins, which further led to less cell apoptosis. This study is the first report showing that MOE has antiviral potential as a new prophylactic and therapeutic strategy against PEDV infection.

Abstract

Porcine epidemic diarrhea (PED), one of the serious enteric diseases caused by the porcine epidemic diarrhea virus (PEDV), is responsible for enormous economic losses in the global swine industry. However, available commercial vaccines fail to protect pigs from PEDV infection due to the appearance of PEDV variants. Hence, it is necessary to find an effective and cost-efficient natural product to protect pigs from PEDV infection. In this study, we first found that an aqueous leaf extract of M. oleifera (MOE) exhibited antiviral activity in response to PEDV infection. Furthermore, time-of-addition experiments revealed that MOE inhibited PEDV replication rather than attachment and internalization. Mechanistically, MOE significantly suppressed the production of reactive oxygen species (ROS) and malondialdehyde (MDA) induced by PEDV infection, and restored glutathione peroxidase (GSH-Px) activity. Importantly, the addition of MOE alleviated oxidative stress and the expression of inflammatory cytokines and resulted in fewer apoptotic cells during PEDV infection. These results indicated that MOE might be an effective anti-PEDV drug used to control PED disease and may be helpful in developing a new prophylactic and therapeutic strategy against PEDV.

The Autophagosomes Containing Dengue Virus Proteins and Full-Length Genomic RNA Are Infectious

Autophagic machinery is involved in selective and non-selective recruitment as well as degradation or exocytosis of cargoes, including pathogens. Dengue virus (DENV) infection induces autophagy that enhances virus replication and vesicle release to evade immune system surveillance. This study reveals that DENV2 induces autophagy in lung and liver cancer cells and showed that DENV2 capsid, envelope, NS1, NS3, NS4B and host cell proinflammatory high mobility group box 1 (HMGB1) proteins associated with autophagosomes which were purified by gradient centrifugation. Capsid, NS1 and NS3 proteins showing high colocalization with LC3 protein in the cytoplasm of the infected cells were detected in the purified double-membrane autophagosome by immunogold labeling under transmission electron microscopy. In DENV infected cells, the levels of capsid, envelope, NS1 and HMGB1 proteins are not significantly changed compared to the dramatic accumulation of LC3-II and p62/SQSTM1 proteins when autophagic degradation was blocked by chloroquine, indicating that these proteins are not regulated by autophagic degradation machinery. We further demonstrated that purified autophagosomes were infectious when co-cultured with uninfected cells. Notably, these infectious autophagosomes contain DENV2 proteins, negative-strand and full-length genomic RNAs, but no viral particles. It is possible that the infectivity of the autophagosome originates from the full-length DENV RNA. Moreover, we reveal that DENV2 promotes HMGB1 exocytosis partially through secretory autophagy. In conclusion, we are the first to report that DENV2-induced double-membrane autophagosomes containing viral proteins and full-length RNAs are infectious and not undergoing autophagic degradation. Our novel finding warrants further validation of whether these intracellular vesicles undergo exocytosis to become infectious autophagic vesicles.

microRNAs, the Link Between Dengue Virus and the Host Genome

Dengue virus (DENV) is a small envelope virus of Flaviviridae that is mainly transmitted by Aedes aegypti and Aedes albopictus. It can cause dengue fever with mild clinical symptoms or even life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). At present, there are no specific drugs or mature vaccine products to treat DENV. microRNAs (miRNAs) are a class of important non-coding small molecular RNAs that regulate gene expression at the post-transcriptional level. It is involved in and regulates a series of important life processes, such as growth and development, cell differentiation, cell apoptosis, anti-virus, and anti-tumor. miRNAs also play important roles in interactions between host and viral genome transcriptomes. Host miRNAs can directly target the genome of the virus or regulate host factors to promote or inhibit virus replication. Understanding the expression and function of miRNAs during infection with DENV and the related signal molecules of the miRNA-mediated regulatory network will provide new insights for the development of miRNA-based therapies.

Phytoconstituents as Lead Compounds for Anti-Dengue Drug Discovery

Dengue is an arthropod-borne viral disease common in subtropical and tropical regions. The widespread use of traditional medicines in these regions for dengue fever (DF) has encouraged researchers to explore the therapeutic effect of herbs and their phytochemicals in dengue infection. Phytochemicals such as quercetin, baicalein, luteolin, oxindole alkaloids, celastrol and geraniin have shown significant inhibition of dengue virus in vitro. Many phytoconstituents have better selectivity index supporting their safety profile for future development. However, in vivo studies supporting therapeutic potency for these active phytoconstituents are limited. There is a need for studies translating anti-dengue profile of active phytoconstituents to find successful anti-dengue compounds.

Broad Anti-Viral Capacities of Lian-Hua-Qing-Wen Capsule and Jin-Hua-Qing-Gan Granule and Rational use Against COVID-19 Based on Literature Mining

The novel coronavirus disease 2019 (COVID-19) has become a matter of international concern as the disease is spreading exponentially. Statistics showed that infected patients in China who received combined treatment of Traditional Chinese Medicine and modern medicine exhibited lower fatality rate and relatively better clinical outcomes. Both Lian-Hua-Qing-Wen Capsule (LHQWC) and Jin-Hua-Qing-Gan Granule (JHQGG) have been recommended by China Food and Drug Administration for the treatment of COVID-19 and have played a vital role in the prevention of a variety of viral infections. Here, we desired to analyze the broad-spectrum anti-viral capacities of LHQWC and JHQGG, and to compare their pharmacological functions for rational clinical applications. Based on literature mining, we found that both LHQWC and JHQGG were endowed with multiple antiviral activities by both targeting viral life cycle and regulating host immune responses and inflammation. In addition, from literature analyzed, JHQGG is more potent in modulating viral life cycle, whereas LHQWC exhibits better efficacies in regulating host anti-viral responses. When translating into clinical applications, oral administration of LHQWC could be more beneficial for patients with insufficient immune functions or for patients with alleviated symptoms after treatment with JHQGG.

Glycyrrhizic acid exerts inhibitory activity against the spike protein of SARS-CoV-2

Coronavirus causes a disease with high infectivity and pathogenicity, especially SARS in 2003, MERS in 2012, and COVID-2019 currently. The spike proteins of these coronaviruses are critical for host cell entry by receptors. Thus, searching for broad-spectrum anti-coronavirus candidates, such as spike protein inhibitors, is vital and desirable due to the mutations in the spike protein. In this study, a combination of computer-aided drug design and biological verification was used to discover active monomers from traditional Chinese medicine. Surface plasmon resonance (SPR) assays and NanoBit assays were used to verify the predicated compounds with their binding activities to spike proteins and inhibitory activities on the SARS-CoV-2 RBD/ACE2 interaction, respectively. Furthermore, an MTT assay was used to evaluate the cell toxicities of active compounds. As a result, glycyrrhizic acid (ZZY-44) was found to be the most efficient and nontoxic broad-spectrum anti-coronavirus molecule in vitro, especially, the significant effect on SARS-CoV-2, which provided a theoretical basis for the study of the pharmacodynamic material basis of traditional Chinese medicine against SARS-CoV-2 and offered a lead compound for further structural modification in order to obtain more effective candidate drugs against SARS-CoV-2.

Honeysuckle Aqueous Extracts Induced let-7a Suppress EV71 Replication and Pathogenesis In Vitro and In Vivo and Is Predicted to Inhibit SARS-CoV-2

Honeysuckle (Lonicera japonica Thunb) is a traditional Chinese medicine (TCM) with an antipathogenic activity. MicroRNAs (miRNAs) are small non-coding RNA molecules that are ubiquitously expressed in cells. Endogenous miRNA may function as an innate response to block pathogen invasion. The miRNA expression profiles of both mice and humans after the ingestion of honeysuckle were obtained. Fifteen overexpressed miRNAs overlapped and were predicted to be capable of targeting three viruses: dengue virus (DENV), enterovirus 71 (EV71) and SARS-CoV-2. Among them, let-7a was examined to be capable of targeting the EV71 RNA genome by reporter assay and Western blotting. Moreover, honeysuckle-induced let-7a suppression of EV71 RNA and protein expression as well as viral replication were investigated both in vitro and in vivo. We demonstrated that let-7a targeted EV71 at the predicted sequences using luciferase reporter plasmids as well as two infectious replicons (pMP4-y-5 and pTOPO-4643). The suppression of EV71 replication and viral load was demonstrated in two cell lines by luciferase activity, RT-PCR, real-time PCR, Western blotting and plaque assay. Furthermore, EV71-infected suckling mice fed honeysuckle extract or inoculated with let-7a showed decreased clinical scores and a prolonged survival time accompanied with decreased viral RNA, protein expression and virus titer. The ingestion of honeysuckle attenuates EV71 replication and related pathogenesis partially through the upregulation of let-7a expression both in vitro and in vivo. Our previous report and the current findings imply that both honeysuckle and upregulated let-7a can execute a suppressive function against the replication of DENV and EV71. Taken together, this evidence indicates that honeysuckle can induce the expression of let-7a and that this miRNA as well as 11 other miRNAs have great potential to prevent and suppress EV71 replication.

Combating COVID-19 with integrated traditional Chinese and Western medicine in China

COVID-19, an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread throughout the world. China has achieved rapid containment of this highly infectious disease following the principles of early detection, early quarantine and early treatment with integrated traditional Chinese and Western medicine. The inclusion of traditional Chinese medicine (TCM) in the Chinese protocol is based on its successful historic experience in fighting against pestilence. Current findings have shown that the Chinese medicine can reduce the incidence of severe or critical events, improve clinical recovery and help alleviate symptoms such as cough or fever. To date there are over 133 ongoing registered clinical studies on TCM/integrated traditional Chinese and Western medicine. The three Chinese patent medicines (Lianhua Qingwen Keli/Jiaonang (Forsythiae and Honeysuckle Flower Pestilence-Clearing Granules/Capsules), Jinhua Qinggan Keli (Honeysuckle Flower Cold-Relieving Granules) and Xuebijing (Stasis-Resolving & Toxin-Removing) Injection were officially approved by the National Medical Products Administration to list COVID-19 as an additional indication. The pharmacological studies have suggested that Chinese medicine is effective for COVID-19 probably through its host-directed regulation and certain antiviral effects.

Evaluation of the Adjuvant Efficacy of Natural Herbal Medicine on COVID-19: A Retrospective Matched Case-Control Study

Since the outbreak of Corona Virus Disease 2019 (COVID-19) in Hubei province, the epidemic scale has increased rapidly, and no effective antiviral drug therapy has been identified yet. This study aimed to evaluate the adjuvant efficacy of Natural Herbal Medicine (NHM) combined with Western medicine in the treatment of COVID-19. We performed a retrospective, 1:1 matched, case-control study of the first cohort of hospitalized COVID-19-confirmed cases (January 17, 2020 to January 28, 2020). A total of 22 of the 36 confirmed patients were included in this study, split into two groups of 11: the NHM group (NHM combined standard Western medicine treatment) and control group (standard Western medicine treatment alone). All patients received appropriate supportive care and regular clinical and laboratory monitoring. Main evaluation indicators included improvement of clinical symptoms such as fever, cough and diarrhea after hospitalization; pathogen nucleic acid test result of respiratory tract and fecal specimens of the patient after hospitalization, and change of chest CT examination after hospitalization. The duration of fever in the NHM group ([Formula: see text] days) was significantly shorter than that in the control group ([Formula: see text] days) ([Formula: see text]). During the whole hospitalization period, the number of cases with diarrhea in the NHM group (two cases) was less than that in the control group (eight cases) ([Formula: see text]). Compared with the control group ([Formula: see text]), the duration for improvement (DI) of chest CT in the NHM group ([Formula: see text]) was significantly shorter ([Formula: see text]). Our results suggest that NHM could improve the clinical symptoms of COVID-19 patients and may be effective in treating COVID-19; thus, a larger, prospective, randomized, controlled clinical trial should be conducted to further evaluate the adjuvant efficacy of NHM in the treatment of COVID-19.

Baicalin inhibits influenza virus A replication via activation of type I IFN signaling by reducing miR‑146a

Influenza virus A (IVA) is one of the predominant causative agents of the seasonal flu and has become an important cause of morbidity worldwide. Great efforts have been paid to develop vaccines against IVA. However, due to antigenic drift in influenza virus A and rapid emergence of drug-resistant strains, current available vaccines or anti-IVA chemotherapeutics are consistently inefficient. Hence, various more broadly effective drugs have become important for the prevention and treatment of IVA. Of these drugs, baicalin, a flavonoid isolated from Radix Scutellaria, is a promising example. However, little is known in regards to its pharmacological mechanism. Here, it was demonstrated that baicalin inhibits the H1N1 and H3N2 viruses in A549 cells. Subsequently, it was found that miR-146a was markedly downregulated by treatment of baicalin. Additionally, further experiments revealed that miR-146a was able to promote the replication of H1N1 and H3N2 by targeting TNF receptor-associated factor 6 (TRAF6), a pivotal adaptor in the interferon (IFN) production signaling pathway, to downregulate type I IFN production, and enrichment of miR-146a eliminated the anti-IVA effects of baicalin on the H1N1 and H3N2 viruses. Additionally, in vivo experiments demonstrated that baicalin could protect mice during H1N1 infection. Taken together, our findings firstly illustrated the anti-IVA molecular mechanism of baicalin and provide new evidence for targeting miRNAs to prevent and treat viral infection, such as the H1N1 and H3N2 viruses.

Honeysuckle extract relieves ovalbumin-induced allergic rhinitis by inhibiting AR-induced inflammation and autoimmunity

Honeysuckle has antiviral, antioxidative and anti-inflammatory properties. Allergic rhinitis (AR) is induced by immunoglobulin E (IgE)-mediated inflammatory reaction. Our study investigates whether honeysuckle extract (HE) has therapeutic effect on AR. An AR model of mice was established by ovalbumin (OVA). Hematoxylin-Eosin staining was used to assess nasal mucosa damage. Enzyme-linked immunosorbent assay (ELISA) was performed to determine serum histamine, IgE and interleukin (IL)-2, IL-4, IL-17 and interferon-γ (IFN-γ) from nasal lavage fluid. Western blot was carried out to analyze the protein level from nasal mucosa tissue. We found that HE not only decreased nasal rubbing and sneezing in AR mice, but also reduced AR-induced damage to nasal mucosa. Moreover, HE lowered the levels of serum IgE and histamine and inhibited IL-4 and IL-17 levels from AR mice but raised IL-2 and IFN-γ levels in AR-induced nasal lavage fluid. Our results also showed that HE elevated the protein levels of forkhead box P3 (Foxp3) and T-box transcription factor (T-bet) in AR-induced nasal mucosa tissue, whereas it inhibited signal transducer and activator of transcription (STAT) 3 and GATA binding protein 3 (GATA-3) protein levels. By regulating AR-induced inflammatory reaction and autoimmune response, HE also relieved OVA-induced AR. Thus, HE could be used as a potential drug to treat AR.

A novel miRNA, miR-13664, targets CpCYP314A1 to regulate deltamethrin resistance in Culex pipiens pallens

Extensive insecticide use has led to the resistance of mosquitoes to these insecticides, posing a major barrier to mosquito control. Previous Solexa high-throughput sequencing of Culex pipiens pallens in the laboratory has revealed that the abundance of a novel microRNA (miRNA), miR-13664, was higher in a deltamethrin-sensitive (DS) strain than a deltamethrin-resistant (DR) strain. Real-time quantitative PCR revealed that the miR-13664 transcript level was lower in the DR strain than in the DS strain. MiR-13664 oversupply in the DR strain increased the susceptibility of these mosquitoes to deltamethrin, whereas inhibition of miR-13664 made the DS strain more resistant to deltamethrin. Results of bioinformatic analysis, quantitative reverse-transcriptase polymerase chain reaction, luciferase assay and miR mimic/inhibitor microinjection revealed CpCYP314A1 to be a target of miR-13664. In addition, downregulation of CpCYP314A1 expression in the DR strain reduced the resistance of mosquitoes to deltamethrin. Taken together, our results indicate that miR-13664 could regulate deltamethrin resistance by interacting with CpCYP314A1, providing new insights into mosquito resistance mechanisms.