Radix isatidis Polysaccharides Inhibit Influenza a Virus and Influenza A Virus-Induced Inflammation via Suppression of Host TLR3 Signaling In Vitro

Targeting chemokine-receptor mediated molecular signaling by ethnopharmacological approaches

ETHNOPHARMACOLOGICAL RELEVANCE

Infection and inflammation are critical to global human health status and the goal of current pharmacological interventions intends formulating medications/preventives as a measure to deal with this situation. Chemokines and their cognate receptors are major regulatory molecules in many of these ailments. Natural products have been a keen source to the drug development industry, every year contributing significantly to the growing list of FDA approved drugs. A multiverse of natural resource is employed as a part of curative regimen in folk/traditional/ethnomedicine which can be employed to discover, repurpose, and design potent medications for the diseases of clinical concern.

AIM OF THE STUDY

This review aims to systematically document the ethnopharmacologically active agents targeting the infectious-inflammatory diseases through the chemokine-receptor nexus.

MATERIALS AND METHODS

Articles related to chemokine/receptor modulating ethnopharmacological anti-inflammatory, anti-infectious natural sources, bioactive compounds, and formulations have been examined with special emphasis on women related diseases. The available literature has been thoroughly scrutinized for the application of traditional medicines in chemokine associated experimental methods, their regulatory outcomes, and pertinence to women's health wherever applicable. Moreover, the potential traditional regimens under clinical trials have been critically assessed.

RESULTS

A systematic and comprehensive review on the chemokine-receptor targeting ethnopharmaceutics from the available literature has been provided. The article discusses the implication of traditional medicine in the chemokine system dynamics in diverse infectious-inflammatory disorders such as cardiovascular diseases, allergic diseases, inflammatory diseases, neuroinflammation, and cancer. On this note, critical evaluation of the available data surfaced multiple diseases prevalent in women such as osteoporosis, rheumatoid arthritis, breast cancer, cervical cancer and urinary tract infection. Currently there is no available literature highlighting chemokine-receptor targeting using traditional medicinal approach from women's health perspective. Moreover, despite being potent in vitro and in vivo setups there remains a gap in clinical translation of these formulations, which needs to be strategically and scientifically addressed to pave the way for their successful industrial translation.

CONCLUSIONS

The review provides an optimistic global perspective towards the applicability of ethnopharmacology in chemokine-receptor regulated infectious and inflammatory diseases with special emphasis on ailments prevalent in women, consecutively addressing their current status of clinical translation and future directions.

Clinical efficacy, pharmacodynamic components, and molecular mechanisms of antiviral granules in the treatment of influenza: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

The Antiviral Granules (AG) are derived from the classical famous prescription, which is composed of 9 traditional Chinese medicines, namely Radix Isatidis (called Banlangen, BLG in Chinese), Forsythiae Fructus (called Lianqiao, LQ in Chinese), Gypsum fibrosum, Anemarrhenae Rhizoma (called Zhimu, ZM in Chinese), Phragmitis Rhizoma (called Lugen, LG in Chinese), Rehmanniae Radix (called Dihuang, DH in Chinese), Pogostemonis Herba (called Guanghuoxiang, GHX in Chinese), Acori Tatarinowii Rhizoma (called Shichangpu, SCP in Chinese), and Curcumae Radix (called Yujin, YJ in Chinese), and has shown an excellent therapeutic effect in clinical treatment of influenza. However, there are few studies on the anti-influenza mechanism of AG, and the mechanism of action is still unclear.

AIM OF THE STUDY

The purpose is to provide the latest information about the clinical efficacy, pharmacodynamic composition and mechanism of AG based on scientific literature, so as to enhance the utilization of AG in the treatment of influenza and related diseases, and promote the development and innovation of novel anti-influenza drugs targeting the influenza virus.

MATERIALS AND METHODS

Enter the data retrieval room, search for Antiviral Granules, as well as the scientific names, common names, and Chinese names of each Chinese medicine. Additionally, search for the relevant clinical applications, pharmacodynamic composition, pharmacological action, and molecular mechanism of both Antiviral Granules and single-ingredient medicines. Keywords includes terms such as "antiviral granules", "influenza", "Isatis indigotica Fort.", "Radix Isatidis", "Banlangeng", "pharmacology", "clinical application", "pharmacologic action", etc. and their combinations. Obtain results from the Web of Science, PubMed, Google Scholar, Sci Finder Scholar, CNKI and other resources.

RESULTS

AG is effective in the treatment of influenza and is often used in combination with other drugs to treat viral diseases. Its chemical composition is complex, including alkaloids, polysaccharides, volatile oils, steroid saponins, phenylpropanoids, terpenoids and other compounds. These compounds have a variety of pharmacological activities, which can interfere with the replication cycle of the influenza virus, regulate RIG-I-MAVS, JAK/STAT, TLRs/MyD88, NF-κB signaling pathways and related cytokines, regulate intestinal microorganisms, and protect both the lungs and extrapulmonary organs.

CONCLUSIONS

AG can overcome the limitations of traditional antiviral drug therapy, play a synergistic role in fighting influenza virus with the characteristics of multi-component, multi-pathway and multi-target therapy, and reverse the bodily function damage caused by influenza virus. AG may be a potential drug in the prevention and treatment of influenza and related diseases.

The role and mechanism of TCM in the prevention and treatment of infectious diseases

The constant presence of infectious diseases poses an everlasting threat to the entire world. In recent years, there has been an increased attention toward the application of traditional Chinese medicine (TCM) in the treatment of emerging infectious diseases, as it has played a significant role. The aim of this article is to provide a concise overview of the roles and mechanisms of TCM in treating infectious diseases. TCM possesses the ability to modulate relevant factors, impede signaling pathways, and inhibit microbial growth, thereby exhibiting potent antiviral, antibacterial, and anti-inflammatory effects that demonstrate remarkable efficacy against viral and bacterial infections. This article concludes that the comprehensive regulatory features of Chinese herbal medicines, with their various components, targets, and pathways, result in synergistic effects. The significance of Chinese herbal medicines in the context of infectious diseases should not be underestimated; however, it is crucial to also acknowledge their underutilization. This paper presents constructive suggestions regarding the challenges and opportunities faced by Chinese medicines. Particularly, it emphasizes the effectiveness and characteristics of Chinese medicines in the treatment of infectious diseases, specifying how these medicines' active substances can be utilized to target infectious diseases. This perspective is advantageous in facilitating researchers' pharmacological studies on Chinese medicines, focusing on the specific points of action. The mechanism of action of Chinese herbal medicines in the treatment of infectious diseases is comprehensively elucidated in this paper, providing compelling evidence for the superior treatment of infectious diseases through Chinese medicine. This information is favorable for advancing the development of TCM and its potential applications in the field of infectious diseases.

Portulaca oleracea L. Polysaccharide Inhibits Porcine Rotavirus In Vitro

Diarrhea is one of the most common causes of death in young piglets. Porcine rotavirus (PoRV) belongs to the genus Rotavirus within the family Reoviridae, and is considered to be the primary pathogen causing diarrhea in piglets. Portulaca oleracea L. (POL) has been reported to alleviate diarrhea and viral infections. However, the antiviral effect of Portulaca oleracea L. polysaccharide (POL-P), an active component of POL, on PoRV infection remains unclear. This study demonstrated that the safe concentration range of POL-P in IPEC-J2 cells is 0-400 μg/mL. POL-P (400 μg/mL) effectively inhibits PoRV infection in IPEC-J2 cells, reducing the expression of rotavirus VP6 protein, mRNA and virus titer. Furthermore, on the basis of viral life cycle analysis, we showed that POL-P can decrease the expression of PoRV VP6 protein, mRNA, and virus titer during the internalization and replication stages of PoRV. POL-P exerts antiviral effects by increasing IFN-α expression and decreasing the expression levels of TNF-α, IL-6, and IL-10 inflammatory factors. Overall, our study found that POL-P is a promising candidate for anti-PoRV drugs.

Immunomodulatory and antiviral effects of Lycium barbarum glycopeptide on influenza a virus infection

Influenza is caused by a respiratory virus and has a major global impact on human health. Influenza A viruses in particular are highly pathogenic to humans and have caused multiple pandemics. An important consequence of infection is viral pneumonia, and with serious complications of excessive inflammation and tissue damage. Therefore, simultaneously reducing direct damage caused by virus infection and relieving indirect damage caused by excessive inflammation would be an effective treatment strategy. Lycium barbarum glycopeptide (LbGp) is a mixture of five highly branched polysaccharide-protein conjuncts (LbGp1-5) isolated from Lycium barbarum fruit. LbGp has pro-immune activity that is 1-2 orders of magnitude stronger than that of other plant polysaccharides. However, there are few reports on the immunomodulatory and antiviral activities of LbGp. In this study, we evaluated the antiviral and immunomodulatory effects of LbGp in vivo and in vitro and investigated its therapeutic effect on H1N1-induced viral pneumonia and mechanisms of action. In vitro, cytokine secretion, NF-κB p65 nuclear translocation, and CD86 mRNA expression in LPS-stimulated RAW264.7 cells were constrained by LbGp treatment. In A549 cells, LbGp can inhibit H1N1 infection by blocking virus attachment and entry action. In vivo experiments confirmed that administration of LbGp can effectively increase the survival rate, body weight and decrease the lung index of mice infected with H1N1. Compared to the model group, pulmonary histopathologic symptoms in lung sections of mice treated with LbGp were obviously alleviated. Further investigation revealed that the mechanism of LbGp in the treatment of H1N1-induced viral pneumonia includes reducing the viral load in lung, regulating the phenotype of pulmonary macrophages, and inhibiting excessive inflammation. In conclusion, LbGp exhibits potential curative effects against H1N1-induced viral pneumonia in mice, and these effects are associated with its good immuno-regulatory and antiviral activities.

Characterization of isolated starch from Isatis indigotica Fort. root and anhydro-sugars preparation using its decoction residues

Isatis indigotica Fort. root (Ban-lan-gen, IIR), a traditional Chinese medicine (TCM), has an ancient and well-documented history for its medicinal properties. Aside from epigoitrin, indole alkaloids, and their corresponding derivatives as medicinal ingredients, it also contains lots of biomass such as starch. Herein, a new starch was isolated from IIR and the physicochemical properties such as amylose content, moisture content, ash content, morphology, thermal properties, and crystallography were characterized systematically. The amylose content of IIR starch was 19.84 ± 0.85%, and the size and shape of starch granules is ellipsoidal shape with sizes from 2 to 10 μm. IIR starch exhibited a C-type pattern and had 25.92% crystallinity (higher than that of corn starch). The gelatinization temperature of IIR starch was 58.68-75.41 °C, and its gelatinization enthalpy was ΔH gel = 4.33 J/g. After decocting, the IIR's residues can be used to prepare anhydro-sugars in a polar aprotic solvent. The total carbon yield of levoglucosan (LG), levoglucosenone (LGO), 5-hydroxymethylfurfural (HMF), and furfural (FF) could reach 69.81% from IIR's decoction residues in 1,4-dioxane with 15 mM H2SO4 as the catalyst. Further, the residues after dehydration were prepared into biochar by thermochemical conversion and the BET surface area of biochar was 1749.46 m2/g which has good application prospect in soil improvement and alleviates obstacles of IIR continuous cropping.

Radix Isatidis polysaccharide (RIP) resists the infection of QX-type infectious bronchitis virus via the MDA5/TLR3/IRF7 signaling pathway

Although vaccines play a major role in the prevention of infectious bronchitis (IB), Anti-IB drugs still have great potential in poultry production. Radix Isatidis polysaccharide (RIP) is a crude extract of Banlangen with antioxidant, antibacterial, antiviral, and multiple immunomodulatory functions. The aim of this study was to explore the innate immune mechanisms responsible for RIP-mediated alleviation of infectious bronchitis virus (IBV)-induced kidney lesions in chickens. Specific-pathogen-free (SPF) chicken and chicken embryo kidney (CEK) cells cultures were pretreated with RIP and then infected with the QX-type IBV strain, Sczy3. Morbidity, mortality, and tissue mean lesion scores were calculated for IBV-infected chickens, and the viral loads, inflammatory factor gene mRNA expression levels, and innate immune pathway gene mRNA expression levels in infected chickens and CEK cell cultures were determined. The results show that RIP could alleviate IBV-induced kidney damage, decrease CEK cells susceptibility to IBV infection, and reduce viral loads. Additionally, RIP reduced the mRNA expression levels of the inflammatory factors IL-6, IL-8, and IL-1β by decreasing the mRNA expression level of NF-κB. Conversely, the expression levels of MDA5, TLR3, STING, Myd88, IRF7, and IFN-β were increased, indicating that RIP conferred resistance to QX-type IBV infection via the MDA5, TLR3, IRF7 signaling pathway. These results provide a reference for both further research into the antiviral mechanisms of RIP and the development of preventative and therapeutic drugs for IB.

Adenosine and L-proline can possibly hinder Chinese Sacbrood virus infection in honey bees via immune modulation

Sacbrood virus (SBV) infects larvae of honey bees, resulting in infected larvae becoming fluid-filled sacs. Our previous studies showed that the extract of herbal medicine, Radix Isatidis, could inhibit Chinese SBV (CSBV) infection in Asian honey bees (Apis cerana). Here, two compounds, adenosine and L-proline, which were previously reported to be associated with immune modulation, were identified in R. Isatidis extract and then selected for an evaluation of their antiviral effect on CSBV infection in A. cerana. Our results revealed that both adenosine and L-proline could significantly mitigate the impact of CSBV on the growth and development of infected larvae and modulate hosts' immune responses by downregulating the expression of immune genes in infected larvae. The results gained from this study suggest that adenosine and L-proline could possibly interfere CSBV infection via immune modulation to avoid exacerbations and nonspecific damage to infected larvae's own tissues.

Polysaccharide extract from Isatidis Radix inhibits multiple inflammasomes activation and alleviate gouty arthritis

The polysaccharide extract from Isatidis Radix exhibits potent antiinflammatory and antiviral activities, but the mechanism of Isatidis Radix polysaccharide (IRP) remains obscure. Herein, we reported that IRP blocked the activation of nod-like receptor pyrin domain-containing 3 (NLRP3) inflammasome, leading to the inhibiting of caspase-1 cleavage and IL-1β secretion. Mechanistically, IRP did not inhibit NLRP3 inflammasome through suppressing mitochondrial reactive oxygen species (mtROS) production. However, IRP can significantly suppress the oligomerization of apoptosis-associated speck-like protein (ASC) and subsequently block the formation of inflammasome. Next, we evaluate the role of IRP in monosodium urate (MSU)-induced gout in vivo which is a NLRP3-associated disease. We also observed that oral administration of IRP can reduce the increased ankle thickness and the secretion of IL-1β, IL-18, IL-6, TNF-α and MPO of the mouse ankle joints caused by MSU crystals. Furthermore, flow cytometry analysis highlighted a significant modulation of T helper 17 cells (Th17)/regulatory T cells (Treg) following IRP treatment in MSU induced gout. Overall, our findings suggest that IRP has comprehensive and potent antiinflammatory effects and provide a reasonable therapeutic strategy in preventing inflammasome-associated diseases, such as inflammatory gouty arthritis.

Comparative study of water-soluble polysaccharides isolated from leaves and roots of Isatis indigotica Fort

Water-soluble polysaccharides were isolated from the leaves and roots of Isatis indigotica Fort., and their structural features were studied and compared. One neutral polysaccharide fraction (WFIP-N) and three pectin fractions (WFIP-A-A, WFIP-A-B and WFIP-A-C) were obtained from the leaves, and one neutral polysaccharide fraction (WRIP-N) and two pectin fractions (WRIP-A-A and WRIP-A-B) were obtained from the roots. WFIP-A-B (Mw = 34.6 kDa) and WRIP-A-B (Mw = 29.9 kDa) were the major pectic polysaccharides. Monosaccharide composition, FT-IR, enzymatic hydrolysis, NMR and methylation analysis indicated that both WFIP-A-B and WRIP-A-B are composed of rhamnogalacturonan I (RG-I), rhamnogalacturonan II (RG-II) and homogalacturonan (HG) domains with mass ratios of 1.5:1.0:0.4 and 0.3:1.0:1.7, respectively. WFIP-A-B and WRIP-A-B were found to be rich in RG-I and HG domains, respectively, and mainly contained type II arabinogalactan (AG-II) and α-L-1,5-arabinan side chains, but those in WRIP-A-B were more numerous and longer. Our results provide structural features and differences between these polysaccharides which will help to elucidate their functional differences.

A Systemic Review for Ethnopharmacological Studies on Isatis indigotica Fortune: Bioactive Compounds and their Therapeutic Insights

Isatis indigotica Fortune is a biennial Chinese woad of the Cruciferae family. It is primarily cultivated in China, where it was a staple in indigo dye manufacture till the end of the 17th century. Today, I. indigotica is used primarily as a therapeutic herb in traditional Chinese medicine (TCM). The medicinal use of the plant is separated into its leaves (Da-Qing-Ye) and roots (Ban-Lan-Gen), whereas its aerial components can be processed into a dried bluish-spruce powder (Qing-Dai), following dehydration for long-term preservation. Over the past several decades, I. indigotica has been generally utilized for its heat-clearing effects and bodily detoxification in TCM, attributed to the presence of several classes of bioactive compounds, including organic acids, alkaloids, terpenoids, and flavonoids, as well as lignans, anthraquinones, glucosides, glucosinolates, sphingolipids, tetrapyrroles, and polysaccharides. This paper aims to delineate I. indigotica from its closely-related species (Isatis tinctoria and Isatis glauca) while highlighting the ethnomedicinal uses of I. indigotica from the perspectives of modern and traditional medicine. A systematic search of PubMed, Embase, PMC, Web of Science, and Google Scholar databases was done for articles on all aspects of the plant, emphasizing those analyzing the bioactivity of constituents of the plant. The various key bioactive compounds of I. indigotica that have been found to exhibit anti-inflammatory, antimicrobial, anticancer, and anti-allergic properties, along with the protective effects against neuronal injury and bone fracture, will be discussed. Collectively, the review hopes to draw attention to the therapeutic potential of I. indigotica not only as a TCM, but also as a potential source of bioactive compounds for disease management and treatment.

Isatidis Radix and Isatidis Folium: A systematic review on ethnopharmacology, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Isatidis Radix (called Banlangen, BLG in Chinese) and Isatidis Folium (called Daqingye, DQY in Chinese) are common traditional edible-medicinal herbs in detoxifying for thousands of years, have been traditionally applied in traditional Chinese medicine for centuries. Both of them are bitter in taste, coolness in nature, acting on the heart and stomach channels. They are often used to treat influenza and other viral infectious diseases in clinic, as well as could treat fever, dizziness, and cough and sore throat caused by lung heat.

AIMS OF THE REVIEW

This review aimed at summarizing the latest and comprehensive information of BLG and DQY on the ethnopharmacology, phytochemistry, pharmacology, toxicity and clinical application to explore the therapeutic potential of them. In addition, outlooks and perspective for possible future researches that related are also discussed.

MATERIALS AND METHODS

Related information concerning BLG and DQY were gathered from the internet database of Google Scholar, PubMed, Baidu Scholar, GeenMedical, CNKI and Web of Science, as well as other relevant textbooks, reviews, and documents (e.g., Chinese Pharmacopoeia, 2020 edition, Chinese herbal classic books and PhD and MSc thesis, etc.). Among of them with the keywords including "Isatis indigotica" "Isatidis Radix", "Isatidis Folium", "phytochemistry", "pharmacology", "toxicology", "clinical application" etc. and their combinations.

RESULTS

To date, 39 Chinese patent medicines containing BLG and/or DQY have been developed on basis of the data of NMPA. Besides, 304 and 142 compounds have been found in BLG and DQY, respectively. The main chemical differences between BLG and DQY were concentrated on alkaloids and lignans, such as indican, indirubin, (R, S)-epigoitrin, 4(3H)-quinazolinone, clemastanin B and isatindigotindolines A-D. In 2020 Edition ChP, (R, S)-goitrin and indirubin are now used as the official marker to monitor the quality of BLG and DQY, respectively. Modern pharmacology has mainly studied some monomer components such as 4(3H)-quinazolinone, clemastanin B, erucic acid and adenosine, etc., all of which have shown good effects. These active compounds can resist various viruses, such as influenza virus, respiratory syncytial virus, herpes simplex virus, etc.. By regulating the level of immunity and a variety of inflammatory factors, inhibit the growth and reproduction of the virus. At the same time, it is worth noting that different components of BLG and DQY lead to BLG is more powerful in antiviral and immunomodulatory activity than DQY, while DQY possesses a higher intensity than BLG in anti-oxidant activity.

CONCLUSION

By collecting and collating a large number of literature and various data websites, we concluded that the common compounds are mainly alkaloids. Recent findings regarding the phytochemical and pharmacological properties of BLG and DQY have confirmed their traditional uses in antiviral, antibacterial and treatment immune diseases. Without doubt, their significant differences on ethnopharmacology, phytochemistry and pharmacology can be used as evidence of separate list of BLG and DQY. For shortcomings, some comprehensive studies should be well designed for further utilization of BLG and DQY.

The lncRNA CASC2 Modulates Hepatocellular Carcinoma Cell Sensitivity and Resistance to TRAIL Through Apoptotic and Non-Apoptotic Signaling

The immune cytokine tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been widely concerned as a tumor therapy because of its ability of selective triggering cancer cell apoptosis; nevertheless, hepatocellular carcinoma (HCC) exhibits acquired resistance to TRAIL-induced apoptosis. In the present study, tumor-suppressive lncRNA cancer susceptibility candidate 2 (CASC2) was downregulated in HCC tissues and cell lines; HCC patients with lower CASC2 expression predicted a shorter overall survival rate. In vitro, CASC2 overexpression dramatically repressed HCC cell proliferation and inhibited cell apoptosis; in vivo, CASC2 overexpression inhibited subcutaneous xenotransplant tumor growth. CASC2 affected the caspase cascades and NF-κB signaling in TRAIL-sensitive [Huh-7 (S) and HCCLM3 (S)] or TRAIL-resistant cell lines [Huh-7 (R) and HCCLM3 (R)] in different ways. In Huh-7 (S) and HCCLM3 (S) cells, CASC2 affected cell apoptosis through the miR-24/caspase-8 and miR-221/caspase-3 axes and the caspase cascades. miR-18a directly targeted CASC2 and RIPK1. In Huh-7 (R) and HCCLM3 (R) cells, CASC2 affected cell proliferation through the miR-18a/RIPK1 axis and the NF-κB signaling. RELA bound to CASC2 promoter region and inhibited CASC2 transcription. In conclusion, CASC2 affects cell growth mainly via the miR-24/caspase-8 and miR-221/caspase-3 axes in TRAIL-sensitive HCC cells; while in TRAIL-resistant HCC cells, CASC2 affects cell growth mainly via miR-18a/RIPK1 axis and the NF-κB signaling. These outcomes foreboded that CASC2 could be a novel therapeutic target for further study of HCC-related diseases.

In Silico Prediction and Bioactivity Evaluation of Chemical Ingredients Against Influenza A Virus From Isatis tinctoria L

Influenza A virus (IAV) is one of the major causes of seasonal endemic diseases and unpredictable periodic pandemics. Due to the high mutation rate and drug resistance, it poses a persistent threat and challenge to public health. Isatis tinctoria L. (Banlangen, BLG), a traditional herbal medicine widely used in Asian countries, has been reported to possess strong efficacy on respiratory viruses, including IAV. However, its effective anti-IAV components and the mechanism of actions (MOAs) are not yet fully elucidated. In this study, we first summarized the chemical components and corresponding contents in BLG according to current available chemical analysis literature. We then presented a network-based in silico framework for identifying potential drug candidates against IAV from BLG. A total of 269 components in BLG were initially screened by drug-likeness and ADME (absorption, distribution, metabolism, and excretion) evaluation. Thereafter, network predictive models were built via the integration of compound–target networks and influenza virus–host proteins. We highlighted 23 compounds that possessed high potential as anti-influenza virus agents. Through experimental evaluation, six compounds, namely, eupatorin, dinatin, linarin, tryptanthrin, indirubin, and acacetin, exhibited good inhibitory activity against wild-type H1N1 and H3N2. Particularly, they also exerted significant effects on drug-resistant strains. Finally, we explored the anti-IAV MOAs of BLG and showcased the potential biological pathways by systems pharmacology analysis. In conclusion, this work provides important information on BLG regarding its use in the development of anti-IAV drugs, and the network-based prediction framework proposed here also offers a powerfulful strategy for the in silico identification of novel drug candidates from complex components of herbal medicine.

Immunomodulatory effects of Radix isatidis polysaccharides in vitro and in vivo

Radix isatidis (R. isatidis) is a commonly used traditional Chinese herbal medicine, which has been used for thousands of years in China and is believed to have the pharmacological properties of heat-clearing and detoxification. Heat-clearing and detoxification are theories of traditional Chinese medicine meaning that R. isatidis could treat febrile disease by clearing heat and reducing swelling. Polysaccharides isolated from R. isatidis by water extraction and alcohol precipitation have exhibited numerous biological activities, including antiviral and immunomodulatory effects. The present study was performed to investigate the immunomodulatory effects of water-soluble R. isatidis polysaccharides (RIPs) on RAW264.7 macrophages and murine splenocytes, and attempt to preliminarily identify the mechanism of immunomodulation. In vitro, RIPs had a low cytotoxicity, as shown by CellTiter 96^® AQ_ueous One Solution Cell Proliferation Assay. RAW264.7 cells treated with different concentrations of RIP displayed different morphological changes, from a round shape and aggregation to polygonal shape and dispersion in a dose-dependent manner. In the 5 mg/ml RIP-treated group, the changes of morphology were as same as the lipopolysaccharide-treated group. RIP also significantly enhanced the release of nitric oxide as shown by Griess method, and the secretion of TNF-α and IL-6 in RAW264.7 cells was confirmed by ELISA assay. Western blotting revealed a significant increase of toll-like receptor-4 (TLR-4) in RIP-treated RAW264.7, suggesting that TLR-4 may be associated with the immunomodulatory mechanism of RIP. Animal experiments also demonstrated through ELISA assays a significant increase in IFN-γ and IL-10 levels after the splenocytes of RIP-immunized mice were stimulated by inactivated herpes simplex virus type 2. The immune function of RIP-immunized mice was improved. The present study suggested that RIP could be potentially used as a novel immunomodulator.

Progress in Traditional Chinese Medicine Against Respiratory Viruses: A Review

Respiratory viruses, such as severe acute respiratory syndrome coronavirus (SARS-CoV)-1, SARS-CoV-2, influenza A viruses, and respiratory syncytial virus, pose a serious threat to society. Based on the guiding principles of “holism” and “syndrome differentiation and treatment”, traditional Chinese medicine (TCM) has unique advantages in the treatment of respiratory virus diseases owing to the synergistic effect of multiple components and targets, which prevents drug resistance from arising. According to TCM theory, there are two main strategies in antiviral treatments, namely “dispelling evil” and “fu zheng”. Dispelling evil corresponds to the direct inhibition of virus growth and fu zheng corresponds to immune regulation, inflammation control, and tissue protection in the host. In this review, current progress in using TCMs against respiratory viruses is summarized according to modern biological theories. The prospects for developing TCMs against respiratory viruses is discussed to provide a reference for the research and development of innovative TCMs with multiple components, multiple targets, and low toxicity.

Network pharmacology study on the mechanism of the Chinese medicine Radix Isatidis (Banlangen) for COVID-19

Radix Isatidis (Banlangen) is a well-known traditional Chinese medicine for the treatment of different diseases and prevention of many body disorders. Besides, it also plays a pivotal role in novel coronavirus pneumonia, coronavirus disease 2019 (COVID-19). However, few researchers know its active ingredients and mechanism of action for COVID-19. To find whether Banlangen has a pharmacological effect on COVID-19. In this research, we systematically analyze Banlangen and COVID-19 through network pharmacology technology. A total of 33 active ingredients in Banlangen, 92 targets of the active ingredients, and 259 appropriate targets of COVID-19 were obtained, with 11 common targets. The analysis of the biological process of gene ontology and the enrichment of Kyoto Encyclopedia of Genes and Genomes signaling pathway suggests that Banlangen participated in the biological processes of protein phosphatase binding, tetrapyrrole binding, the apoptotic process involving cysteine-type endopeptidase activity, etc. The COVID-19 may be treated by regulating advanced glycation end products/a receptor for advanced glycation end products signaling pathway, interleukin-17 signaling pathway, tumor necrosis factor signaling pathway, sphingolipid signaling pathway, and p53 signaling pathway. Banlangen has a potential pharmacological effect on COVID-19, which has the value of further exploration in the following experiment and clinical application.

A Network Pharmacology-Based Investigation to the Pharmacodynamic Material Basis and Mechanisms of the Anti-Inflammatory and Anti-Viral Effect of Isatis indigotica

Purpose

Isatis indigotica (Ii) is a cruciferous herb that is widely distributed in China, and its roots and leaves have been used in two renowned antipyretic detoxicate crude drugs in Chinese Pharmacopoeia, Radix (R) and Folium (F) Isatidis. However, the pharmacodynamic material basis and underlying mechanisms of the herbal efficacy remained to be elucidated.

Methods

Ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was adopted for the chemical profiling of R and F Isatidis. The active ingredients were screened out through the prediction of gastrointestinal absorption and druglikeness analysis using SwissADME. A herb-ingredient-target network was constructed through target prediction of the herbal active ingredients and anti-inflammation or anti-viral properties, followed by protein-protein interaction analysis. Then, the potential relevant signaling pathways were predicted by pathway enrichment. Finally, for verification, RAW 264.7 cell line was adopted to examine the anti-inflammatory and anti-viral activities of 6 representative ingredients in Ii.

Results

Seventy-three compounds have been identified from Ii through UPLC-Q-TOF-MS. A total of 17 potential active ingredients were screened through pharmacokinetics and drug-likeness evaluation using SwissADME. It was shown that key targets might include TNF, AKT1, SRC, IL2, CASP9, and CASP3 in our herb-ingredient-target network, and isovitexin, a flavonoid, tended to participate in the inflammatory response, indoles were more likely to affect the cell proliferation processes, and lignans might have a broader affinity to key targets than the other active ingredients, such as regulating immune system (targeting IL-2) and PI3K-Akt signaling pathway. In vitro, indigo and secoisolariciresinol diglucoside markedly reduced TNF-α expression in Poly (I: C)-incubated cells. Isovitexin significantly inhibited TNF-α expression, and isatin treatment markedly reduced IL-1β expression in LPS-incubated cells.

Conclusion

As the pharmacodynamics material basis of Ii, indoles, lignans, and flavonoids are believed to confer beneficial properties through various cellular aspects with multiple signaling pathways involved.

Development of Broad-Spectrum Antiviral Agents-Inspiration from Immunomodulatory Natural Products

Developing broad-spectrum antiviral drugs remains an important issue as viral infections continue to threaten public health. Host-directed therapy is a method that focuses on potential targets in host cells or the body, instead of viral proteins. Its antiviral effects are achieved by disturbing the life cycles of pathogens or modulating immunity. In this review, we focus on the development of broad-spectrum antiviral drugs that enhance the immune response. Some natural products present antiviral effects mediated by enhancing immunity, and their structures and mechanisms are summarized here. Natural products with immunomodulatory effects are also discussed, although their antiviral effects remain unknown. Given the power of immunity and the feasibility of host-directed therapy, we argue that both of these categories of natural products provide clues that may be beneficial for the discovery of broad-spectrum antiviral drugs.

Phytochemical Profiles and their Anti-inflammatory Responses Against Influenza from Traditional Chinese Medicine or Herbs

Traditional Chinese medicine (TCM) or herbs are widely used in the prevention and treatment of viral infectious diseases. However, the underlying mechanisms of TCMs remain largely obscure due to complicated material basis and multi-target therapeutics. TCMs have been reported to display anti-influenza activity associated with immunoregulatory mechanisms by enhancing host antiinfluenza immune responses. Previous studies have helped us understand the direct harm caused by the virus itself. In this review, we have tried to summarize recent progress in TCM-based anti-influenza research on the indirect harmful immune responses caused by influenza viruses. In particular, the phytochemicals from TCMs responsible for molecular mechanisms of action belonging to different classes, including phenolic compounds, flavonoids, alkaloids and polysaccharides, have been identified and demonstrated. In addition, this review focuses on the pharmacological mechanism, e.g., inflammatory responses and the interferon (IFN) signaling pathway, which can provide a theoretical basis and approaches for TCM based anti-influenza treatment.

The indole alkaloids from the roots of Isatidis Radix

The root of Isatis indigotica is used as a traditional Chinese medicine (termed Isatidis Radix) due to its antiviral effects. We examined compounds isolated from Isatidis Radix and elucidated the structures of three new natural alkaloids, and we examined the possible mechanisms or active targets of indole alkaloids occurring in blood of rats treated by gavage. Three new natural products were isolated from Radix Isatidis for the first time, including 1-methoxy-2-indoleacetonitrile, 1-hydroxy-3-indoleacetonitrile, 8-Methoxy-1, 2-dihydroquinoline, and 4 compounds isolated from this medicinal material for the first time. Their structures were elucidated using nuclear magnetic resonance. The components of Isatidis Radix were analysed using liquid chromatography tandem mass spectrometry, and 33 compounds were detected in plasma of treated rats; 24 of these compounds were indole alkaloids, and they included the newly identified compounds. Molecular docking and in vitro antithrombin activity tests showed HA inhibition activity of indoleacetonitriles.

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.

Antiviral Activities of a Medicinal Plant Extract Against Sacbrood Virus in Honeybees

Background

Sacbrood is an infectious disease of the honey bee caused by Scbrood virus (SBV) which belongs to the family Iflaviridae and is especially lethal for Asian honeybee Apis cerana. Chinese Sacbrood virus (CSBV) is a geographic strain of SBV. Currently, there is a lack of an effective antiviral agent for controlling CSBV infection in honey bees.

Methods

Here, we explored the antiviral effect of a Chinese medicinal herb Radix isatidis on CSBV infection in A. cerana by inoculating the 3rd instar larvae with purified CSBV and treating the infected bee larvae with R. isatidis extract at the same time. The growth, development, and survival of larvae between the control and treatment groups were compared. The CSBV copy number at the 4th instar, 5th instar, and 6th instar larvae was measured by the absolute quantification PCR method.

Results

Bioassays revealed that R. isatidis extract significantly inhibited the replication of CSBV, mitigated the impacts of CSBV on larval growth and development, reduced the mortality of CSBV-infected A. cerana larvae, and modulated the expression of immune transcripts in infected bees.

Conclusion

Although the mechanism underlying the inhibition of CSBV replication by the medicine plant will require further investigation, this study demonstrated the antiviral activity of R. isatidis extract and provides a potential strategy for controlling SBV infection in honey bees.

Development and Effects of Influenza Antiviral Drugs

Influenza virus is a highly contagious zoonotic respiratory disease that causes seasonal outbreaks each year and unpredictable pandemics occasionally with high morbidity and mortality rates, posing a great threat to public health worldwide. Besides the limited effect of vaccines, the problem is exacerbated by the lack of drugs with strong antiviral activity against all flu strains. Currently, there are two classes of antiviral drugs available that are chemosynthetic and approved against influenza A virus for prophylactic and therapeutic treatment, but the appearance of drug-resistant virus strains is a serious issue that strikes at the core of influenza control. There is therefore an urgent need to develop new antiviral drugs. Many reports have shown that the development of novel bioactive plant extracts and microbial extracts has significant advantages in influenza treatment. This paper comprehensively reviews the development and effects of chemosynthetic drugs, plant extracts, and microbial extracts with influenza antiviral activity, hoping to provide some references for novel antiviral drug design and promising alternative candidates for further anti-influenza drug development.

Pharmacokinetic Characterization of ZT55, A Novel Indole Derivative Isolated from Radix Isatidis, using Liquid Chromatography/Tandem Mass and Q-TOF/Tandem Mass Spectrometry

Background:

ZT55 is a novel natural product isolated from Radix isatidis. It is a highlyselective tyrosine kinase inhibitor against myeloproliferative neoplasms. Although earlier research has described the pharmacodynamic properties of ZT55 in vivo and in vitro, the quantitative determination and pharmacokinetic profile in vivo have not been thoroughly studied.

Methods:

A novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of ZT55 in rat plasma. A Waters symmetry C18 column was used for chromatographic separation; 0.1% formic acid in acetonitrile and 0.1% formic aqueous solution was used as the mobile phase. Detection was performed by Multiple Reaction Monitoring (MRM) mode using electrospray ionization in the positive ion mode. UPLC-QTOF-MS was used for the identification of metabolites.

Results:

The method was linear (R2=0.9988) over the concentration range of 1-2500 ng/mL. The lower limit of quantification was 1 ng/mL. The intra-day and inter-day precision of ZT55 showed a relative standard deviation within 8.47%, whereas the accuracy (RE) ranged from -4.84% to 4.45%. The recoveries ranged from 92.89% to 97.21%. ZT55 reached the highest plasma concentration at 0.5h. The peak concentrations with three dosages were 103.59±10.11, 185.23±29.56, and 355.98±28.86 ng/mL. The AUC0-24 of three dosages were 874.70±72.33, 433.80±49.33, and 231.65±19.41 ng•h/ml respectively. Five metabolites of ZT55 from plasma were confirmed. The main pathways of ZT55 in vivo were hydrolysis, N-dealkylation, glycosylation, and sulfonation.

Conclusions:

LC-MS/MS method was successfully applied to the pharmacokinetic study of ZT55 after oral administration and intravenous. ZT55 exhibited rapid oral absorption, high elimination, and low absolute bioavailability. This study provides important pharmacokinetic and metabolism information for further pharmacological and toxicological research on ZT55.

Novel Fatty Acid in Cordyceps Suppresses Influenza A (H1N1) Virus-Induced Proinflammatory Response Through Regulating Innate Signaling Pathways

Influenza virus (IV) infections usually cause acute lung injury characterized by exaggerated proinflammatory responses. The paucity of therapeutic strategies that target host immune response to attenuate lung injury poses a substantial challenge in management of IV infections. In this study, we chemically synthesized a novel fatty acid (2Z,4E)-deca-2,4-dienoic acid (DDEA) identified from Chinese Cordyceps by using UHPLC-Q-TOF-MS techniques. The DDEA did not inhibit H1N1 virus replication but attenuated proinflammatory responses by reducing mRNA and protein levels of TNF-α, IFN-α, IFN-β, IL-6, CXCL-8/IL-8, CCL-2/MCP-1, CXCL-10/IP-10, CCL-3/MIP-1α, and CCL-4/MIP-1β in A549 cells and U937-derived macrophages. The anti-inflammatory effect occurred through downregulations of TLR-3-, RIG-I-, and type I IFN-activated innate immune signaling pathways. Altogether, our results indicate that DDEA may potentially be used as an anti-inflammatory therapy for the treatment of IV infections.

Application prospect of polysaccharides in the development of anti-novel coronavirus drugs and vaccines

Since the outbreak of the novel coronavirus disease COVID-19, caused by the SARS-CoV-2 virus, it has spread rapidly worldwide and poses a great threat to public health. This is the third serious coronavirus outbreak in <20 years, following SARS in 2002-2003 and MERS in 2012. So far, there are almost no specific clinically effective drugs and vaccines available for COVID-19. Polysaccharides with good safety, immune regulation and antiviral activity have broad application prospects in anti-virus, especially in anti-coronavirus applications. Here, we reviewed the antiviral mechanisms of some polysaccharides, such as glycosaminoglycans, marine polysaccharides, traditional Chinese medicine polysaccharides, and their application progress in anti-coronavirus. In particular, the application prospects of polysaccharide-based vaccine adjuvants, nanomaterials and drug delivery systems in the fight against novel coronavirus were also analyzed and summarized. Additionally, we speculate the possible mechanisms of polysaccharides anti-SARS-CoV-2, and propose the strategy of loading S or N protein from coronavirus onto polysaccharide capped gold nanoparticles vaccine for COVID-19 treatment. This review may provide a new approach for the development of COVID-19 therapeutic agents and vaccines.

Herbal medicine, a reliable support in COVID therapy

At present, specific therapies for COVID-19 are not well established, being certain only that the immune system plays a decisive role in the initiation and progression of the disease. Plants have given and continue to give compounds with great efficiency and low toxicity, some of them being a starting point for extremely effective synthetic substances. Although herbal remedies are used mainly for preventive purposes, there are also guidelines issued by some countries that indicate the use of traditional remedies for different stages of COVID-19 disease.Europe has a long and strong tradition of using medicinal plants for therapeutic purposes, but clinical trials for this type of approach are scarce, compared to Asia. In this regard, a bridge between tradition and science, would have a strong impact on the capacity for prevention and treatment of COVID-19. The paper reviews compounds of plant origin that have previously proven effective in counteracting some coronaviruses but also some of their major effects - direct action on virus replicative apparatus (viral entry or replication, action on the viral enzymatic system), collateral action of natural compounds on the immune system and also the contribution of herbal medicine as vaccine adjuvants are tackled.

Medicinal Plants to Strengthen Immunity during a Pandemic

The development of new effective anti-coronavirus drugs and therapies is important, but it requires significant human, financial and, most importantly, time expenditures. The current pandemic is neither the first nor the last. Humanity has already accumulated considerable survival experience. We cannot do without prevention and epidemiological protection measures. This study reviews medicinal plants that grow in Northeast Asia and whose antioxidant, antiviral, anti-inflammatory and immunomodulatory characteristics are already known, also in the framework of the prevention and treatment of pneumonia of various etiologies. The need for a comprehensive approach to maintaining immunodefences, including functional foods and positive emotions, is emphasized. In the period of pandemics, it is important to research various areas that allow to us accumulate a critical mass of information and cope with the next global disease.

Multigram Scale Synthesis and Anti-Influenza Activity of 3-Indoleacetonitrile Glucosides

Indole-3-acetonitrile-6- O-β-d-glucopyranoside 1 is a simple alkaloid with anti-influenza A virus activity extracted from Radix isatidis. Herein, a concise and practical total synthetic route of 1 was presented, starting from 6-benzyloxyindole on a multigram scale. The pivotal reaction sequence involved the Mannich reaction, the fluoride ion-induced elimination-addition reaction, and phase-transfer-catalyzed glycosylation reaction as key steps. In addition, compounds 1 and two modified derivatives 8 and 16 were tested for anti-influenza efficacy and cytotoxicity in vitro performed on Madin-Darby canine kidney cells. The results revealed that the compounds exerted antiviral activity against the influenza A virus to a certain extent and displayed no cytotoxicity. These findings could contribute to the development of traditional Chinese medicine R. isatidis for treating the influenza virus.

Total alkaloids from Alstonia scholaris inhibit influenza a virus replication and lung immunopathology by regulating the innate immune response

BACKGROUND

Alstonia scholaris is a folk medicine used to treat cough, asthma and chronic obstructive pulmonary disease in China. Total alkaloids (TA) from A. scholaris exhibit anti-inflammatory properties in acute respiratory disease, which suggests their possible anti-inflammatory effect on influenza virus infection.

PURPOSE

To assess the clinical use of TA by demonstrating their anti-influenza and anti-inflammatory effects and the possible mechanism underlying the effect of TA on influenza A virus (IAV) infection in vitro and to reveal the inhibitory effect of TA on lung immunopathology caused by IAV infection.

METHODS

Antiviral and anti-inflammatory activities were assessed in Madin-Darby canine kidney (MDCK) and A549 cells and U937-derived macrophages infected with influenza A/PR/8/34 (H1N1) virus. Proinflammatory cytokine levels were measured by real-time quantitative PCR and Bio-Plex assays. The activation of innate immune signaling induced by H1N1 virus in the absence or presence of TA was detected in A549 cells by Western blot. Furthermore, mice were infected intranasally with H1N1 virus and treated with TA (50, 25 and 12.5 mg/kg/d) or oseltamivir (60 mg/kg/d) for 5 days in vivo. The survival rates and body weight were recorded, and the viral titer, proinflammatory cytokine levels, innate immune cell populations and histopathological changes in the lungs were analyzed.

RESULTS

TA significantly inhibited viral replication in A549 cells and U937-derived macrophages and markedly reduced cytokine and chemokine production at the mRNA and protein levels. Furthermore, TA blocked the activation of pattern recognition receptor (PRR)- and IFN-activated signal transduction in A549 cells. Critically, TA also increased the survival rate, reduced the viral titer, suppressed proinflammatory cytokine production and innate immune cell infiltration and improved lung histopathology in a lethal PR8 mouse model.

CONCLUSION

TA exhibits anti-viral and anti-inflammatory effects against IAV infection by interfering with PRR- and IFN-activated signal transduction.

Traditional Herbal Medicine for the Prevention and Treatment of Cold and Flu in the Autumn of 2020, Overlapped With COVID-19

Many herbs and plants included in several traditional systems have promising bioactive compounds for modern drug therapy. The second round of COVID-19 cases will be accompanied by the spread of seasonal influenza in the fall. The combination of the influenza season and the second wave of COVID-19 may lead to more confusion and put more pressure on public health systems. A literature survey was accomplished using multiple databases including PubMed, Science Direct, ISI web of knowledge, and Google Scholar. The most important antiviral herbs for cold and flu are Thymus vulgaris, honeysuckle flowers, Andrographis, yarrow, peppermint leaf and oil, and Calendula. The most important expectorant herbs for flu and cold are tulsi, snake root, licorice root, clove, slippery elm root, marshmallow osha root, and sage leaf. Immunostimulant herbs for these 2 diseases are Echinacea root, Eucalyptus, garlic, ginseng, marshmallow, slippery elm, Isatisroot, Usnea lichen, myrrh resin, and ginger root. In this mini-review, we mention the key role of some of the most important herbal plants and prescriptions against influenza and cold on the basis of traditional Asian medicine.

Antiviral activity of a polysaccharide from Radix Isatidis (Isatis indigotica Fortune) against hepatitis B virus (HBV) in vitro via activation of JAK/STAT signal pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Hepatitis B virus (HBV) infection frequently results in both acute and chronic hepatitis and poses serious threats to human health worldwide. Despite the availability of effective HBV vaccine and anti-HBV drugs, apparently inevitable side effects and resistance have limited its efficiency, thus prompt the search for new anti-HBV agents. The traditional Chinese medicine Radix Isatidis has been used for thousands of years, mainly for the treatment of viral and bacterial infection diseases including hepatitis.

AIM OF THE STUDY

In this study, antiviral activities of a Radix Isatidis (Isatis indigotica Fortune) polysaccharide (RIP) were evaluated in vitro model using the HepG2.2.15 cell line and the underlying mechanism was elucidated with the aim of developing a novel anti-HBV therapeutic agent.

MATERIALS AND METHODS

Structure features of the purified polysaccharide RIP were investigated by a combination of chemical and instrumental analysis. Drug cytotoxicity was assessed using the MTT assay. The contents of HBsAg, HBeAg, intracellular and extracellular IFN-α level were measured using respective commercially available ELISA kit. The HBV DNA expression was evaluated by real-time quantitative polymerase chain reaction (PCR) and the relevant proteins involved in TFN/JAK/STAT signaling pathways were examined by western blot assay.

RESULTS

MTT assay showed that RIP had no toxicity on HepG2.2.15 cell line below the concentration 400 μg/ml at Day 3, 6 and 9. Furthermore, RIP at the concentration of 50, 100 and 200 μg/ml significantly reduced extracellular and intracellular level of HBsAg, HBeAg and HBV DNA in HepG2.2.15 cells in a time and dose-dependent manner. Moreover, RIP also enhanced the production of IFN-α in HepG2.2.15 cell via activation of JAK/STAT signal pathway and induction of antiviral proteins, as evidenced by the increased protein expression of p-STAT-1, p-STAT-2, p-JAK1, p-TYK2, OAS1, and Mx in HepG2.2.15 cells. In addition, the over expression of SOCS-1 and SOCS-3 was significantly abolished under same conditions.

CONCLUSIONS

These results suggested that the HBV inhibitory effect of RIP was possibly due to the activation of IFN-α-dependent JAK/STAT signal pathway and induction of the anti-HBV protein expression.

Principles and treatment strategies for the use of Chinese herbal medicine in patients at different stages of coronavirus infection

Coronavirus disease 2019 (COVID-19) is a novel, human-infecting β-coronavirus enveloped, positive-sense single-stranded RNA viruses, similar to the severe acute respiratory syndrome (SARS) infection that emerged in November 2002. In traditional Chinese medicine (TCM), the epidemic disease concepts of "febrile epidemics" (wenyi) or "warm diseases" (wenbing) are based on geographic and cultural aspects, and Chinese herbal medicine (CHM) played an important role in the treatment of epidemic diseases. CHM was widely used to treat patients suffered with SARS almost two decades ago during outbreak of SARS, with proven safety and potential benefits. TCM has also been widely used to treat cancer patients for a long history and much of them associate with immunomodulatory activity and are used to treat coronavirus-related diseases. We propose the use of CHM treatment principles for clinical practice, based on four main stages of COVID-19 infection: early, intermediate, severe, and convalescence. We suggest corresponding decoctions that exhibit antiviral activity and anti-inflammatory effects in the early stage of infection; preventing the disease from progressing from an intermediate to severe stage of infection; restoring normal lung function and improving consciousness in the severe stage; and ameliorating pulmonary and vascular injury in the convalescent stage. We summarize the pharmaceutical mechanisms of CHM for treating coronavirus via antiviral, anti-inflammatory and immunomodulatory effects.

Sophorasubprosrate polysaccharide suppress the inflammatory reaction of RAW264.7 cells infected with PCV2 via regulation NF-κB/MAPKs/c-Jun signal pathway and histone acetylation modification

The purpose of this study was to investigate the regulation of Sophorasubprosrate polysaccharide (SSP) on inflammatory response and histone acetylation modification of RAW264.7 cells (mouse mononuclear macrophage cell line) infected with porcine circovirus type 2 (PCV2). We further explored the role of inflammatory response and histone acetylation modification on the basis of the original study. The results showed that SSP decreased the secretion levels of TNF-α and IL-6 and the intracellular iNOS, COX-2 enzyme activities and their mRNA expression levels in PCV2 infected RAW264.7 cells, but increased the level of IL-10 secretion and its mRNA expression. SSP inhibited the phosphorylation levels of proteins of p65, ERK1/2, p38 and c-Jun in RAW264.7 cells infected with PCV2. The activities of HAT and HDAC enzymes and the mRNA expression levels of HAT1 and HDAC1 were increased when the PCV2-infected RAW264.7 cells were treated by SSP. Meanwhile, the expression of acetylation modification of histones both H3 and H4 was obviously inhibited. In conclusion, SSP may reduce the acetylation levels of both H3 and H4 and activate NF-κB/MAPKs/c-Jun signaling pathway by increasing the activity of HADC enzyme and the expression of HDAC mRNA, further inhibiting inflammatory response by regulating the gene expression levels of inflammatory factors. The findings indicated that the molecular mechanism of how traditional Chinese medicine polysaccharide regulates inflammatory signal pathways and inflammatory factors by regulating histone acetylation.

Anti-influenza A virus mechanism of three representative compounds from Flos Trollii via TLRs signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Flos Trollii is the dried flowers of Trollius chinensis. It has been used as a traditional herbal medicine for the treatment of upper respiratory tract infection, tonsillitis and pharyngitis in China for a long history. Veratric acid, vitexin, and trolline are the representative compounds of phenolic acids, flavonoids and alkaloids in this herbal medicine. All of these three compounds show antiviral activity which is related to the efficacy of Flos Trollii.

AIM OF THE STUDY

To investigate the anti-influenza A virus mechanism of the three representative compounds from the perspective of regulating TLRs signaling pathways, so as to understand the relevant efficacy of Flos Trollii.

MATERIALS AND METHODS

Influenza A virus A/FM/1/47 (H1N1) and mouse peritoneal macrophages (RAW264.7) were used in the whole process of investigation. MTT assay was conducted to select the appropriate experimental concentrations of the three compounds on RAW264.7 cells. Western blot, RT-PCR, and ELISA assays were performed to determine the protein and mRNA expression of key factors and related inflammatory factors of TLRs signaling pathways. Griess method was employed to detect the production of NO.

RESULTS

The three representative compounds reduced the inflammatory factors including NO, IL-6, and TNF-α and enhanced the production of IFN-β through dynamically regulating the TLRs 3, 4 and 7 pathways. Veratric acid significantly down-regulated the protein expression of TLR3 and IRF3 as well as the mRNA expression of TBK1 and TRIF. Vitexin significantly down-regulated the protein expression of TBK1 and IRF3 as well as the mRNA expression of TLR3, TBK1, TRIF and IRF3 while up-regulated the protein expression of TLR4 and IKKα. Trolline significantly down-regulated the protein expression of TLR7 whereas significantly up-regulated the protein expression of TLR4, IKKα and TAK1.

CONCLUSIONS

The three representative compounds from Flos Trollii play their parts in anti-H1N1 viral effect through partially down-regulating TLRs 3 and 7 pathways and up-regulating TLR4 pathway. They counteract the inflammatory injury caused by excessive production of NO, IL-1, IL-6, and TNF-α induced by virus infection and enhance the production of IFN-β so as to eliminate the virus.

Antiviral activity of Isatidis Radix derived glucosinolate isomers and their breakdown products against influenza A in vitro/ovo and mechanism of action

ETHNOPHARMACOLOGICAL RELEVANCE

Isatidis Radix, the sun-dried roots of Isatis indigotica Fortune ex Lindl., is one of the most usually used traditional Chinese medicines. For centuries, the herb has been employed in clinical practice for treatment of virus infection and inflammation. However, its active ingredients remain unclear.

AIM OF THE STUDY

In the present study, the anti-influenza virus activity of epiprogoitrin, progoitrin, epigoitrin and goitrin, the Isatidis Radix derived glucosinolate isomers and their breakdown products, was firstly evaluated in vitro and in ovo and their mechanism of action was investigated.

MATERIALS AND METHODS

Epiprogoitrin, progoitrin, epigoitrin and goitrin were isolated from Isatidis Radix by chiral separation. In vitro and in ovo evaluations were performed on Madin-Darby canine kidney (MDCK) cells and embryonated eggs respectively, both using protocols including prevention, treatment and virus neutralization. Hemagglutination (HA) and neuraminidase (NA) inhibition assays were performed for further understanding of the antiviral mechanism.

RESULTS

Isatidis Radix derived glucosinolate isomers and their breakdown products all exhibited dose-dependent inhibition effect against influenza A virus (H1N1) without toxicity. The antiviral potency of the components was in the order of progoitrin > goitrin > epigoitrin > epiprogoitrin. The attachment of the constituents to the viral envelope conduced to the mechanism of their antiviral action without disturbing viral adsorption or budding.

CONCLUSION

Taken together, these results are promising for further development of Isatidis Radix and may contribute an adjunct to pharmacotherapy for influenza virus infection.

Lianhuaqingwen exerts anti-viral and anti-inflammatory activity against novel coronavirus (SARS-CoV-2)

PURPOSE

Lianhuaqingwen (LH) as traditional Chinese medicine (TCM) formula has been used to treat influenza and exerted broad-spectrum antiviral effects on a series of influenza viruses and immune regulatory effects Ding et al. (2017). The goal of this study is to demonstrate the antiviral activity of LH against the novel SARS-CoV-2 virus and its potential effect in regulating host immune response.

METHODS

The antiviral activity of LH against SARS-CoV-2 was assessed in Vero E6 cells using CPE and plaque reduction assay. The effect of LH on virion morphology was visualized under transmission electron microscope. Pro-inflammatory cytokine expression levels upon SARS-CoV-2 infection in Huh-7 cells were measured by real-time quantitative PCR assays.

RESULTS

LH significantly inhibited SARS-CoV-2 replication in Vero E6 cells and markedly reduced pro-inflammatory cytokines (TNF-α, IL-6, CCL-2/MCP-1 and CXCL-10/IP-10) production at the mRNA levels. Furthermore, LH treatment resulted in abnormal particle morphology of virion in cells.

CONCLUSIONS

LH significantly inhibits the SARS-COV-2 replication, affects virus morphology and exerts anti-inflammatory activity in vitro. These findings indicate that LH protects against the virus attack, making its use a novel strategy for controlling the COVID-19 disease.

Isatis tinctoria L. (Woad): A Review of its Botany, Ethnobotanical Uses, Phytochemistry, Biological Activities, and Biotechnological Studies

Isatis tinctoria L. (Brassicaceae), which is commonly known as woad, is a species with an ancient and well-documented history as an indigo dye and medicinal plant. Currently, I. tinctoria is utilized more often as medicinal remedy and also as a cosmetic ingredient. In 2011, I. tinctoria root was accepted in the official European phytotherapy by introducing its monograph in the European Pharmacopoeia. The biological properties of raw material have been known from Traditional Chinese Medicine (TCM). Over recent decades, I. tinctoria has been investigated both from a phytochemical and a biological point of view. The modern in vitro and in vivo scientific studies proved anti-inflammatory, anti-tumour, antimicrobial, antiviral, analgesic, and antioxidant activities. The phytochemical composition of I. tinctoria has been thoroughly investigated and the plant was proven to contain many valuable biologically active compounds, including several alkaloids, among which tryptanthrin, indirubin, indolinone, phenolic compounds, and polysaccharides as well as glucosinolates, carotenoids, volatile constituents, and fatty acids. This article provides a general botanical and ethnobotanical overview that summarizes the up-to-date knowledge on the phytochemistry and biological properties of this valuable plant in order to support its therapeutic potential. Moreover, the biotechnological studies on I. tinctoria, which mainly focused on hairy root cultures for the enhanced production of flavonoids and alkaloids as well as on the establishment of shoot cultures and micropropagation protocols, were reviewed. They provide input for future research prospects.

Yansuanmalingua inhibits replication of type 2 porcine reproductive and respiratory syndrome virus via activating the caspase-8 apoptosis pathway

Porcine reproductive and respiratory syndrome virus (PRRSV) causes significant economic losses to the pork industry. The present study showed that Yansuanmalingua (YASML) can inhibit type 2 PRRSV replication using plaque assay, quantitative reverse transcriptase-polymerase chain reaction, and immunofluorescence assay. Furthermore, inhibition of PRRSV replication was shown to be related to Toll-like receptor 3 (TLR3)-dependent apoptosis-induction by YASML in the PRRSV-infected MARC-145, and TLR3-dependent apoptosis-induction by YASML was found to suppress PRRSV replication via the activation of caspase-8 and caspase-3 pathways, respectively. Meanwhile, activation of the caspase-3 pathway seemed to be related to the downregulation of myeloid cell leukemia 1 (Mcl-1) expression. Our results showed that YASML-induced TLR3-dependent apoptosis could be blocked by a pan-caspase inhibitor and small interfering RNA against TLR3. In conclusion, the present study demonstrates that YASML exerts its anti-PRRSV effect by activating the caspase-8/caspase-3 signaling pathway and by negatively regulating Mcl-1 expression. These findings not only provide new insights into the molecular mechanism of YASML inhibition of PRRSV replication via the TLR3-dependent apoptosis pathway but also suggest potential, new antiviral drugs by expressing caspase-3 or down expressing Mcl-1.

Antiviral activities of Radix isatidis polysaccharide against pseudorabies virus in swine testicle cells

Background

Radix isatidis has been used in China and other Asian countries for its antiviral and anti-inflammatory effects for thousands of years. However, the antiviral effect of Radix isatidis polysaccharide against pseudorabies virus (PRV) is still unknown.

Methods

The polysaccharide were isolated from extract of the roots of Radix isatidis. MTT assays were used to determine the preventive effect, inhibitory effect and antiviral effect of Radix isatidis polysaccharide on PRV in vitro.

Results

This study found that different concentrations of polysaccharides from this plant can inhibit PRV replication by 14.674–30.840%, prevent infection at rates of 6.668–14.923%, and kill this virus at rates of 32.214–67.422%.

Conclusion

These results broaden the understanding of this traditional Chinese herb and provide a theoretical basis for further research. Moreover, Radix isatidis polysaccharide could be used for antiviral therapy.

Erucic acid from Isatis indigotica Fort. suppresses influenza A virus replication and inflammation in vitro and in vivo through modulation of NF-κB and p38 MAPK pathway

Isatis indigotica Fort. (Ban-Lan-Gen) is an herbal medicine prescribed for influenza treatment. However, its active components and mode of action remain mostly unknown. In the present study, erucic acid was isolated from Isatis indigotica Fort., and subsequently its underlying mechanism against influenza A virus (IAV) infection was investigated in vitro and in vivo. Our results demonstrated that erucic acid exhibited broad-spectrum antiviral activity against IAV resulting from reduction of viral polymerase transcription activity. Erucic acid was found to exert inhibitory effects on IAV or viral (v) RNA-induced pro-inflammatory mediators as well as interferons (IFNs). The molecular mechanism by which erucic acid with antiviral and anti-inflammatory properties was attributed to inactivation of NF-κB and p38 MAPK signaling. Furthermore, the NF-κB and p38 MAPK inhibitory effect of erucic acid led to diminishing the transcriptional activity of interferon-stimulated gene factor 3 (ISGF-3), and thereby reducing IAV-triggered pro-inflammatory response amplification in IFN-β-sensitized cells. Additionally, IAV- or vRNA-triggered apoptosis of alveolar epithelial A549 cells was prevented by erucic acid. In vivo, erucic acid administration consistently displayed decreased lung viral load and viral antigens expression. Meanwhile, erucic acid markedly reduced CD8⁺ cytotoxic T lymphocyte (CTL) recruitment, pro-apoptotic signaling, hyperactivity of multiple signaling pathways, and exacerbated immune inflammation in the lung, which resulted in decreased lung injury and mortality in mice with a mouse-adapted A/FM/1/47-MA(H1N1) strain infection. Our findings provided a mechanistic basis for the action of erucic acid against IAV-mediated inflammation and injury, suggesting that erucic acid may have a therapeutic potential in the treatment of influenza.

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Erucic acid from Isatis indigotica Fort. exhibited broad-spectrum anti-influenza virus activity.

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Erucic acid reduced IAV polymerase transcription activity.

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Erucic acid suppressed IAV-triggered inflammation as well as pro-inflammatory amplification effects in IFN-sensitized cells.

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Erucic acid protected mice from lethal IAV infection.

Effect of Radix isatidis polysaccharide on alleviating insulin resistance in type 2 diabetes mellitus cells and rats

OBJECTIVES

The objective of this paper was to explore the effects of Radix isatidis polysaccharide (RIP) extracted from Radix isatis on alleviating insulin resistance.

METHODS

The insulin resistance models of 3T3-L1 preadipocytes and type 2 diabetic rats were established to evaluate the insulin resistance activity of RIP.

KEY FINDINGS

Radix isatidis polysaccharide within the concentration range of 25-100 μg/ml could reduce cell supernatant glucose and TNF-α levels (P < 0.01) and increase the expression of PI-3K P85, Glut4, IRS-1 and Akt protein in symptoms of IR 3T3-L1 preadipocytes. In the meantime, RIP contributed to relieve the weight loss of diabetic rats whose liver weight and liver index were decreased due to the effects of RIP. Experiments in rats also showed that RIP had capacity in reduced serum TC, TG, LDL-C, FFA, FBG, FINS, MDA, ALT, AST activities and increased serum HDL-C, SOD, ISI (P < 0.05 or 0.01). In addition, the oral glucose tolerance in rats was improved (P < 0.05) and liver damage was restored due to RIP.

CONCLUSIONS

Radix isatidis polysaccharide significantly alleviates insulin resistance in 3T3-L1 preadipocytes and type 2 diabetic rats. These beneficial effects of RIP may associate with their roles in improving the glucose metabolism, lipid metabolism and oxidative stress.

Complexes of Oligoribonucleotides with d-Mannitol Modulate the Innate Immune Response to Influenza A Virus H1N1 (A/FM/1/47) In Vivo

Rapid replication of the influenza A virus and lung tissue damage caused by exaggerated pro-inflammatory host immune responses lead to numerous deaths. Therefore, novel therapeutic agents that have anti-influenza activities and attenuate excessive pro-inflammatory responses that are induced by an influenza virus infection are needed. Oligoribonucleotides-d-mannitol (ORNs-d-M) complexes possess both antiviral and anti-inflammatory activities. The current research was aimed at studying the ORNs-d-M effects on expression of innate immune genes in mice lungs during an influenza virus infection. Expression of genes was determined by RT-qPCR and Western blot assays. In the present studies, we found that the ORNs-d-M reduced the influenza-induced up-expression of Toll-like receptors (TLRs) (tlr3, tlr7, tlr8), nuclear factor NF-kB (nfkbia, nfnb1), cytokines (ifnε, ifnk, ifna2, ifnb1, ifnγ, il6, il1b, il12a, tnf), chemokines (ccl3, ccl4, сcl5, cxcl9, cxcl10, cxcl11), interferon-stimulated genes (ISGs) (oas1a, oas2, oas3, mx1), and pro-oxidation (nos2, xdh) genes. The ORNs-d-M inhibited the mRNA overexpression of tlr3, tlr7, and tlr8 induced by the influenza virus, which suggests that they impair the upregulation of NF-kB, cytokines, chemokines, ISGs, and pro-oxidation genes induced by the influenza virus by inhibiting activation of the TLR-3, TLR-7, and TLR-8 signaling pathways. By impairing activation of the TLR-3, TLR-7, and TLR-8 signaling pathways, the ORNs-d-M can modulate the innate immune response to an influenza virus infection.

Advancements in Host-Based Interventions for Influenza Treatment

Influenza is a major acute respiratory infection that causes mortality and morbidity worldwide. Two classes of conventional antivirals, M2 ion channel blockers and neuraminidase inhibitors, are mainstays in managing influenza disease to lessen symptoms while minimizing hospitalization and death in patients with severe influenza. However, the development of viral resistance to both drug classes has become a major public health concern. Vaccines are prophylaxis mainstays but are limited in efficacy due to the difficulty in matching predicted dominant viral strains to circulating strains. As such, other potential interventions are being explored. Since viruses rely on host cellular functions to replicate, recent therapeutic developments focus on targeting host factors involved in virus replication. Besides controlling virus replication, potential targets for drug development include controlling virus-induced host immune responses such as the recently suggested involvement of innate lymphoid cells and NADPH oxidases in influenza virus pathogenesis and immune cell metabolism. In this review, we will discuss the advancements in novel host-based interventions for treating influenza disease.