Therapeutic effect of arctiin and arctigenin in immunocompetent and immunocompromised mice infected with influenza A virus

Arctigenin from Forsythia viridissima Fruit Inhibits the Replication of Human Coronavirus

Coronavirus can cause various diseases, from mild symptoms to the recent severe COVID-19. The coronavirus RNA genome is frequently mutated due to its RNA nature, resulting in many pathogenic and drug-resistant variants. Therefore, many medicines should be prepared to respond to the various coronavirus variants. In this report, we demonstrated that Forsythia viridissima fruit ethanol extract (FVFE) effectively reduces coronavirus replication. We attempted to identify the active compounds and found that actigenin from FVFE effectively reduces human coronavirus replication. Arctigenin treatment can reduce coronavirus protein expression and coronavirus-induced cytotoxicity. These results collectively suggest that arctigenin is a potent natural compound that prevents coronavirus replication.

Anthriscus sylvestris-Noxious Weed or Sustainable Source of Bioactive Lignans?

Anthriscus sylvestris (L.) Hoffm. (Apiaceae), commonly known as wild chervil, has gained scientific interest owing to its diverse phytochemical profile and potential therapeutic applications. The plant, despite being categorized as a noxious weed, is traditionally used in treating various conditions like headaches, dressing wounds, and as a tonic, antitussive, antipyretic, analgesic, and diuretic. Its pharmacological importance stems from containing diverse bioactive lignans, especially aryltetralins and dibenzylbutyrolactones. One of the main compounds of A. sylvestris, deoxypodophyllotoxin, among its wide-ranging effects, including antitumor, antiproliferative, antiplatelet aggregation, antiviral, anti-inflammatory, and insecticidal properties, serves as a pivotal precursor to epipodophyllotoxin, crucial in the semisynthesis of cytostatic agents like etoposide and teniposide. The main starting compound for these anticancer medicines was podophyllotoxin, intensively isolated from Sinopodophyllum hexandrum, now listed as an endangered species due to overexploitation. Since new species are being investigated as potential sources, A. sylvestris emerges as a highly promising candidate owing to its abundant lignan content. This review summarizes the current knowledge on A. sylvestris, investigating its biological and morphological characteristics, and pharmacological properties. Emphasizing the biological activities and structure-activity relationship, this review underscores its therapeutic potential, thus encouraging further exploration and utilization of this valuable plant resource.

Protective effect of arctiin against Toxoplasma gondii HSP70-induced allergic acute liver injury by disrupting the TLR4-mediated activation of cytosolic phospholipase A2 and platelet-activating factor

Toxoplasma gondii (T. gondii)-derived heat shock protein 70 (T.g.HSP70) is a toxic protein that downregulates host defense responses against T. gondii infection. T.g.HSP70 was proven to induce fatal anaphylaxis in T. gondii infected mice through cytosolic phospholipase A2 (cPLA2) activated-platelet-activating factor (PAF) production via Toll-like receptor 4 (TLR4)-mediated signaling. In this study, we investigated the effect of arctiin (ARC; a major lignan compound of Fructus arctii) on allergic liver injury using T.g.HSP70-stimulated murine liver cell line (NCTC 1469) and a mouse model of T. gondii infection. Localized surface plasmon resonance, ELISA, western blotting, co-immunoprecipitation, and immunofluorescence were used to investigate the underlying mechanisms of action of ARC on T. gondii-induced allergic acute liver injury. The results showed that ARC suppressed the T.g.HSP70-induced allergic liver injury in a dose-dependent manner. ARC could directly bind to T.g.HSP70 or TLR4, interfering with the interaction between these two factors, and inhibiting activation of the TLR4/mitogen-activated protein kinase/nuclear factor-kappa B signaling, thereby inhibiting the overproduction of cPLA2, PAF, and interferon-γ. This result suggested that ARC ameliorates T.g.HSP70-induced allergic acute liver injury by disrupting the TLR4-mediated activation of inflammatory mediators, providing a theoretical basis for ARC therapy to improve T.g.HSP70-induced allergic liver injury.

Anthriscus sylvestris Deoxypodophyllotoxin Synthase Involved in the Podophyllotoxin Biosynthesis

Tetrahydrofuran ring formation from dibenzylbutyrolactone lignans is a key step in the biosynthesis of aryltetralin lignans including deoxypodophyllotoxin and podophyllotoxin. Previously, Fe(II)- and 2-oxoglutarate-dependent dioxygenase (2-ODD) from Podophyllum hexandrum (Himalayan mayapple, Berberidaceae) was found to catalyze the cyclization of a dibenzylbutyrolactone lignan, yatein, to give deoxypodophyllotoxin and designated as deoxypodophyllotoxin synthase (DPS). Recently, we reported that the biosynthesis of deoxypodophyllotoxin and podophyllotoxin evolved in a lineage-specific manner in phylogenetically unrelated plant species such as P. hexandrum and Anthriscus sylvestris (cow parsley, Apiaceae). Therefore, a comprehensive understanding of the characteristics of DPSs that catalyze the cyclization of yatein to deoxypodophyllotoxin in various plant species is important. However, for plant species other than P. hexandrum, the isolation of the DPS enzyme gene and the type of the enzyme, e.g. whether it is 2-ODD or another type of enzyme such as cytochrome P-450, have not been reported. In this study, we report the identification and characterization of A. sylvestris DPS (AsDPS). Phylogenetic analysis showed that AsDPS belonged to the 2-ODD superfamily and shared moderate amino acid sequence identity (40.8%) with P. hexandrum deoxypodophyllotoxin synthase (PhDPS). Recombinant protein assay indicated that AsDPS and PhDPS differ in terms of the selectivity of substrate enantiomers. Protein modeling using AlphaFold2 and site-directed mutagenesis indicated that the Tyr305 residue of AsDPS probably contributes to substrate recognition. This study advances our understanding of the podophyllotoxin biosynthetic pathway in A. sylvestris and provides new insight into 2-ODD involved in plant secondary (specialized) metabolism.

Promising Therapeutic Treatments for Cardiac Fibrosis: Herbal Plants and Their Extracts

Cardiac fibrosis is closely associated with multiple heart diseases, which are a prominent health issue in the global world. Neurohormones and cytokines play indispensable roles in cardiac fibrosis. Many signaling pathways participate in cardiac fibrosis as well. Cardiac fibrosis is due to impaired degradation of collagen and impaired fibroblast activation, and collagen accumulation results in increasing heart stiffness and inharmonious activity, leading to structure alterations and finally cardiac function decline. Herbal plants have been applied in traditional medicines for thousands of years. Because of their naturality, they have attracted much attention for use in resisting cardiac fibrosis in recent years. This review sheds light on several extracts from herbal plants, which are promising therapeutics for reversing cardiac fibrosis.

A systematic review on botany, ethnopharmacology, quality control, phytochemistry, pharmacology and toxicity of Arctium lappa L. fruit

ETHNOPHARMACOLOGICAL RELEVANCE

Arctium lappa L., is a biennial plant that grows around the Eurasia. Many parts of Arctium lappa L. (roots, leaves and fruits, etc.) are medically used in different countries. Arctium lappa L. fruit, also called Arctii Fructus, is traditionally applied to dispel wind-heat, ventilate lung to promote eruption, remove toxicity substance and relieve sore throat.

THE AIM OF THE REVIEW

The review aims to integrate the botany, ethnopharmacology, quality control, phytochemistry, pharmacology, derivatives and toxicity information of Arctii Fructus, so as to facilitate future research and explore the potential of Arctii Fructus as an agent for treating diseases.

MATERIALS AND METHODS

Related knowledge about Arctii Fructus were acquired from Science Direct, GeenMedical, PubMed, China National Knowledge Infrastructure (CNKI), Web of Science, Pharmacopoeia of the People's Republic of China, Doctoral and Master's thesis, ancient books, etc. RESULTS: Arctii Fructus as an herb used for medicine and food was pervasively distributed and applicated around the world. It was traditionally used to treat anemopyretic cold, dyspnea and cough, sore throat, etc. To date, more than 200 compounds have been isolated and identified from Arctii Fructus. It contained lignans, phenolic acids and fatty acids, terpenoids, volatile oils and others. Lignans, especially arctigenin and arctiin, had the extensive pharmacological effects such as anti-cancer, antiviral, anti-inflammatory activities. The ester derivatives of arctigenin had the anti-cancer, anti-Alzheimer's disease and immunity enhancing effects. Although Arctii Fructus extract had no toxicity, arctigenin was toxic at a certain dose. The alleviating effects of Arctii Fructus on chronic inflammation and ageing have been demonstrated by clinical studies.

CONCLUSION

Arctii Fructus is regarded as a worthy herb with many chemical components and various pharmacological effects. Several traditional applications have been supported by modern pharmacological research. However, their action mechanisms need to be further studied. Although many chemical components were isolated from Arctii Fructus, the current research mainly focused on lignans, especially arctiin and arctigenin. Therefore, it is very important to deeply clarify the pharmacological activities and action mechanism of the compounds and make full medicinal use of the resources of Arctii Fructus.

Preclinical Evidence that Arctigenin Effectively and Selectively Targets Clear Cell Renal Cell Carcinoma Via Suppressing EGFR and RhoA

Clear cell renal cell carcinoma (ccRCC) has poor clinical outcomes and necessitates new treatment options. Epidermal growth factor receptor (EGFR) is a potential therapeutic target, due to the associations with various carcinomas' progression. Arctigenin, a natural compound of Arctium lappa, has been shown to display anticancer abilities in various carcinomas. Cellular assays and combination studies were conducted using arctigenin and anti-ccRCC drugs. In vivo efficacy of arctigenin was determined using ccRCC xenograft mouse model. Immunoblotting and biochemistry analysis were applied to investigate the signaling affected by arctigenin. Arctigenin inhibits growth, migration, and survival of ccRCC cells while sparing normal kidney cells. Arctigenin acts synergistically with 5-FU and sorafenib but not temsirolimus in inhibiting ccRCC cells. Synergism of arctigenin with 5-FU and sorafenib was further shown in ccRCC xenograft mouse model. The combination of arctigenin with clinical anti-RCC drugs completely inhibits tumor growth without tumor progression even for an extended time period. Mechanistically, arctigenin inhibits migration in a RhoA-dependent manner while inhibits growth via suppressing EGFR-mediated signaling pathways. Our findings suggest that arctigenin performs well to add to current treatment in ccRCC and confirm the value to target EGFR to improve therapy in RCC.

Arctiin-encapsulated DSPE-PEG bubble-like nanoparticles inhibit alveolar epithelial type 2 cell senescence to alleviate pulmonary fibrosis via the p38/p53/p21 pathway

Background: Idiopathic pulmonary fibrosis is a severe and deadly form of diffuse parenchymal lung disease and treatment options are few. Alveolar epithelial type 2 (AEC2) cell senescence is implicated in the pathogenies of IPF. A major bioactive compound from the traditional Chinese medicine Fructus arctii, arctiin (ARC) has robust anti-inflammatory, anti-senescence, and anti-fibrosis functions. However, the potential therapeutic effects of ARC on IPF and the underlying mechanisms involved are still unknown.

Methods: First of all, ARC was identified as an active ingredient by network pharmacology analysis and enrichment analysis of F. arctii in treating IPF. We developed ARC-encapsulated DSPE-PEG bubble-like nanoparticles (ARC@DPBNPs) to increase ARC hydrophilicity and achieve high pulmonary delivery efficiency. C57BL/6 mice were used to establish a bleomycin (BLM)-induced pulmonary fibrosis model for assessing the treatment effect of ARC@DPBNPs on lung fibrosis and the anti-senescence properties of AEC2. Meanwhile, p38/p53 signaling in AEC2 was detected in IPF lungs, BLM-induced mice, and an A549 senescence model. The effects of ARC@DPBNPs on p38/p53/p21 were assessed in vivo and in vitro.

Results: Pulmonary route of administration of ARC@DPBNPs protected mice against BLM-induced pulmonary fibrosis without causing significant damage to the heart, liver, spleen, or kidney. ARC@DPBNPs blocked BLM-induced AEC2 senescence in vivo and in vitro. The p38/p53/p21 signaling axis was significantly activated in the lung tissues of patients with IPF, senescent AEC2, and BLM-induced lung fibrosis. ARC@DPBNPs attenuated AEC2 senescence and pulmonary fibrosis by inhibiting the p38/p53/p21 pathway.

Conclusion: Our data suggest that the p38/p53/p21 signaling axis plays a pivotal role in AEC2 senescence in pulmonary fibrosis. The p38/p53/p21 signaling axis inhibition by ARC@DPBNPs provides an innovative approach to treating pulmonary fibrosis in clinical settings.

Specialized metabolites from plants as a source of new multi-target antiviral drugs: a systematic review

Viral infections have always been the main global health challenge, as several potentially lethal viruses, including the hepatitis virus, herpes virus, and influenza virus, have affected human health for decades. Unfortunately, most licensed antiviral drugs are characterized by many adverse reactions and, in the long-term therapy, also develop viral resistance; for these reasons, researchers have focused their attention on investigating potential antiviral molecules from plants. Natural resources indeed offer a variety of specialized therapeutic metabolites that have been demonstrated to inhibit viral entry into the host cells and replication through the regulation of viral absorption, cell receptor binding, and competition for the activation of intracellular signaling pathways. Many active phytochemicals, including flavonoids, lignans, terpenoids, coumarins, saponins, alkaloids, etc., have been identified as potential candidates for preventing and treating viral infections. Using a systematic approach, this review summarises the knowledge obtained to date on the in vivo antiviral activity of specialized metabolites extracted from plant matrices by focusing on their mechanism of action.

In vitro and in vivo evaluation of the antiviral activity of arctigenin, ribavirin, and ivermectin against viral hemorrhagic septicemia virus infection

Viral hemorrhagic septicemia virus (VHSV) causes a severe and often lethal infection in olive flounder (Paralichthys olivaceus) in Korea, resulting in mass mortality and substantial economic loss. As a potential prevention strategy for infectious viral diseases, this study aimed to evaluate the antiviral activity of three compounds (arctigenin [ARG], ribavirin [RBV], and ivermectin [IVM]) against VHSV infection in vitro and in vivo. In epithelioma papulosum cyprini cells, the expression of both VHSV glycoprotein (G) and nucleoprotein (N) genes were significantly suppressed by the three compounds in a dose-dependent manner (P < 0.05). Also, cell morphology and viability were maintained at the following concentrations: ARG 1.5 mg/L, RBV 2.5 mg/L, and IVM 10 mg/L. The fish that were treated with RBV (8.33 mg/kg) and IVM (0.25 mg/kg) before VHSV infection and those treated with IVM (0.25 mg/kg) after VHSV infection showed significant improvements in the survival rate, a reduction in the viral shedding rate, and downregulation of viral gene expression compared to those seen in fish with naïve VHSV infections. Furthermore, among the innate immune genes studied, persistent expression of Mx and upregulation of tumor necrosis factor-α gene expression in VHSV-infected fish treated with RBV and IVM revealed that these compounds might induce an immunostimulatory effect as one of their antiviral activities. Overall, this study supports the use of RBV and IVM as antiviral agents to control VHSV infections in olive flounder.

Arctigenin: pharmacology, total synthesis, and progress in structure modification

Arctium lappa L. is a prevalent medicinal herb and a health supplement that is commonly used in Asia. Over the last few decades, the bioactive component arctigenin has attracted the attention of researchers because of its anti-inflammatory, antioxidant, immunomodulatory, multiple sclerosis fighting, antitumor, and anti-leukemia properties. After summarising the research and literature on arctigenin, this study outlines the current status of research on pharmacological activity, total synthesis, and structural modification of arctigenin. The purpose of this study is to assist academics in obtaining a more comprehensive understanding of the research progress on arctigenin and to provide constructive suggestions for further investigation of this useful molecule.

In vitro and in vivo inhibition of a novel arctigenin derivative on aquatic rhabdovirus

Spring viraemia of carp virus (SVCV) poses a serious threat to aquaculture industry due to the lack of approved antiviral treatments. Therefore, a novel arctigenin derivative, 4-(2-methylimidazole) octanoxy-arctigenin (MON), was synthesized to assess the antiviral activity against SVCV in vitro and in vivo. The results indicated MON decreased the SVCV glycoprotein (G) gene expression in vitro by a maximum inhibitory rate of > 99% at 3.5 μM. Furthermore, MON showed the protective effect on epithelioma papulosum cyprinid (EPC) cells and considerably decreased the cytopathic effect (CPE). More importantly, MON inhibited SVCV G gene expression levels in vitro at the half-maximal activity (IC₅₀) of 0.18 μM at 48 h. For in vivo studies, MON demonstrated anti-SVCV activity by enhancing the survival rate of zebrafish (Danio rerio) after infection via pelvic fin base injection. These results tended to be consistent with MON decreasing the SVCV titer of infected zebrafish. During this time, viral loads of the spleen and kidney have declined in SVSV-infected zebrafish. Based on the histopathological assay, MON exhibited the high protective effect in the spleen and kidney of SVCV-infected fish. Combined, MON is on track to become a novel agent to address SVCV infection in aquaculture.

Arctiin elevates osteogenic differentiation of MC3T3-E1 cells by modulating cyclin D1

Osteoporosis is a systemic disorder of bone metabolism. This study aimed to investigate the impacts and possible mechanisms of Arctiin, a lignin isolated from Arctium lappa on MC3T3-E1 osteoblast differentiation. In this study, after treatment with different concentrations of Arctiin, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting were used to estimate the expression of osteogenesis markers. Then, the activity of alkaline phosphatase (ALP) was detected by an ALP assay kit and calcium nodules staining was evaluated by alizarin red staining (ARS). Additionally, the regulatory effects of Arctiin on cyclin D1 (Ccnd1) was assessed by measurement of protein expression. Subsequently, the functions of Ccnd1 silencing on the osteogenic differentiation was examined in Arctiin-treated MC3T3-E1 cells. Results indicated that Arctiin dose-dependently upregulated the expression of runt-related transcription factor 2 (RUNX2), collagen type 1 (COL1A1), osteocalcin (OCN) and osteopontin (OPN). Elevated ALP activity and calcification degree was prominently observed in the Arctiin-treated groups. Moreover, Ccnd1 expression was notably enhanced after Arctiin intervention. Importantly, Ccnd1-knockdown abrogated the impacts of Arctiin on osteogenic differentiation of MC3T3-E1. To conclude, findings in this study suggested that Arctiin could regulate MC3T3-E1 osteoblast differentiation via up-regulating Ccnd1, supporting that Arctiin might be a therapeutic target for osteoporosis.

Characterization of chemical components and the potential anti-influenza mechanism of Fructus Arctii by a strategy integrating pharmacological evaluations, chemical profiling, serum pharmacochemistry, and network pharmacology

Chemical components in traditional Chinese medicine (TCM) were the functional basis for its therapy achievement, and the absorbed components under disease conditions were mainly contributing to the therapeutic effects. As...

Plant-derived lignans as potential antiviral agents: a systematic review

Medicinal plants are one of the most important sources of antiviral agents and lead compounds. Lignans are a large class of natural compounds comprising two phenyl propane units. Many of them have demonstrated biological activities, and some of them have even been developed as therapeutic drugs. In this review, 630 lignans, including those obtained from medicinal plants and their chemical derivatives, were systematically reviewed for their antiviral activity and mechanism of action. The compounds discussed herein were published in articles between 1998 and 2020. The articles were identified using both database searches (e.g., Web of Science, Pub Med and Scifinder) using key words such as: antiviral activity, antiviral effects, lignans, HBV, HCV, HIV, HPV, HSV, JEV, SARS-CoV, RSV and influenza A virus, and directed searches of scholarly publisher's websites including ACS, Elsevier, Springer, Thieme, and Wiley. The compounds were classified on their structural characteristics as 1) arylnaphthalene lignans, 2) aryltetralin lignans, 3) dibenzylbutyrolactone lignans, 4) dibenzylbutane lignans, 5) tetrahydrofuranoid and tetrahydrofurofuranoid lignans, 6) benzofuran lignans, 7) neolignans, 8) dibenzocyclooctadiene lignans and homolignans, and 9) norlignans and other lignoids. Details on isolation and antiviral activities of the most active compounds within each class of lignan are discussed in detail, as are studies of synthetic lignans that provide structure-activity relationship information.

Antidiarrheal and Cardio-Depressant Effects of Himalaiella heteromalla (D.Don) Raab-Straube: In Vitro, In Vivo, and In Silico Studies

Himalaiella heteromalla (D.Don) Raab-Straube is a commonly used remedy against various diseases. Crude extract and fractions of H. heteromalla were investigated for a gastrointestinal, bronchodilator, cardiovascular, and anti-inflammatory activities. H. heteromalla crude extract (Hh.Cr) relaxed spontaneous contractions and K+ (80 mM)-induced contraction in jejunum tissue dose-dependently. The relaxation of K+ (80 mM) indicates the presence of Ca++ channel blocking (CCB) effect, which was further confirmed by constructing calcium response curves (CRCs) as they caused rightward parallel shift of CRCs in a manner comparable to verapamil, so the spasmolytic effect of Hh.Cr was due to its CCB activity. Application of Hh.Cr on CCh (1 µM) and K+ (80 mM)-induced contraction in tracheal preparation resulted in complete relaxation, showing its bronchodilator effect mediated through Ca++ channels and cholinergic antagonist activity. Application of Hh.Cr on aortic preparations exhibited vasorelaxant activity through angiotensin and α-adrenergic receptors blockage. It also showed the cardio suppressant effect with negative chronotropic and inotropic response in paired atrium preparation. Similar effects were observed in in vivo models, i.e., decreased propulsive movement, wet feces, and inhibition of edema formation.

Anti-inflammatory activity of arctigenin against PCV2 infection in a mouse model

Arctigenin (ACT) is a novel anti-inflammatory lignan extracted from Arctium lappa L, a herb commonly used in traditional Chinese herbal medicine. In this study, we investigated the molecular mechanism whereby ACT inhibits PCV2 infection-induced proinflammatory cytokine production in vitro and in vivo. We observed that in PCV2 infection+ACT treated PK-15 cells, proinflammatory cytokine production was significantly reduced, compared to the PCV2-infected cells. The transfection and luciferase reporter assay confirmed that ACT suppressed NF-κB signalling pathway activation following PCV2 infection in PK-15 cells. Furthermore, western blotting demonstrated that ACT suppressed the NF-κB signal pathway in PCV2 infection-stimulated PK-15 cells by inhibiting the translocation of p65 from the cytoplasm to the nucleus and IκBα phosphorylation. BALB/c mice were used as a model to evaluate the anti-inflammatory effect of ACT in vivo. We found that the BALB/c mice inoculated with PCV2 infection + ACT treated showed a significant reduction of proinflammatory cytokine production in serum, lung and spleen tissue, compared to the PCV2-infected mice. Western blotting confirmed that ACT suppressed the NF-κB signal pathway in PCV2-infected mice by inhibiting the translocation of p65 from the cytoplasm to the nucleus and IκBα phosphorylation in lung tissue. Our studies first demonstrate that ACT inhibits PCV2 infection-induced proinflammatory cytokine production by suppressing the phosphorylation and nuclear translocation of NF-κB in vitro and in vivo. These results will help further develop ACT as a Traditional Chinese herbal medicine remedy in the treatment of porcine circovirus-associated diseases.

Arctiin suppresses H9N2 avian influenza virus-mediated inflammation via activation of Nrf2/HO-1 signaling

BACKGROUND

H9N2 avian influenza viruses (AIVs) infect avian and mammalian hosts and provide internal genes for new emerging highly pathogenic avian viruses that cause severe pneumonia with high mortality, for which few medications are available. Arctiin, a bioactive lignan glycoside, has been reported to possess multiple pharmacological properties. However, the effect of arctiin on H9N2 virus infection is unclear. In the current study, we analyzed the effect of arctiin on H9N2 virus infection and the underlying molecular mechanism in vitro.

METHODS

The antiviral effect against H9N2 virus was determined by plaque reduction assay (PRA) and progeny virus reduction assay. We employed MTT assay, qRT-PCR, ELISA, immunofluorescence and Western blotting to better understand the anti-inflammatory effect and corresponding mechanism of arctiin on H9N2 virus-infected cells.

RESULTS

The results showed that arctiin had antiviral activity against H9N2 virus. Arctiin treatment reduced H9N2 virus-triggered proinflammatory cytokines, such as IL-6, and TNF-α. Moreover, arctiin significantly suppressed H9N2 virus-mediated expression of COX-2 and PGE₂. Furthermore, we found that arctiin inhibited H9N2 virus-mediated activation of RIG-I/JNK MAPK signaling. Interestingly, arctiin treatment obviously reversed H9N2 virus-induced reduction of Nrf2, increased the nuclear translocation of Nrf2, and upregulated Nrf2 signaling target genes (HO-1 and SOD2). Zinc protoporphyrin (Znpp)-an HO-1 inhibitor-weakened the inhibitory effect of arctiin on H9N2 virus-induced RIG-I/JNK MAPK and proinflammatory mediators.

CONCLUSION

Taken together, these results suggested that the anti-inflammatory effects of arctiin on H9N2 virus infection may be due to the activation of Nrf2/HO-1 and blocked RIG-I/JNK MAPK signaling; thus, arctiin may be a promising agent for prevention and treatment of H9N2 virus infections.

Dietary Phytoestrogens and Their Metabolites as Epigenetic Modulators with Impact on Human Health

The impact of dietary phytoestrogens on human health has been a topic of continuous debate since their discovery. Nowadays, based on their presumptive beneficial effects, the amount of phytoestrogens consumed in the daily diet has increased considerably worldwide. Thus, there is a growing need for scientific data regarding their mode of action in the human body. Recently, new insights of phytoestrogens’ bioavailability and metabolism have demonstrated an inter-and intra-population heterogeneity of final metabolites’ production. In addition, the phytoestrogens may have the ability to modulate epigenetic mechanisms that control gene expression. This review highlights the complexity and particularity of the metabolism of each class of phytoestrogens, pointing out the diversity of their bioactive gut metabolites. Futhermore, it presents emerging scientific data which suggest that, among well-known genistein and resveratrol, other phytoestrogens and their gut metabolites can act as epigenetic modulators with a possible impact on human health. The interconnection of dietary phytoestrogens’ consumption with gut microbiota composition, epigenome and related preventive mechanisms is discussed. The current challenges and future perspectives in designing relevant research directions to explore the potential health benefits of dietary phytoestrogens are also explored.

Fructus arctii: an overview on its traditional uses, pharmacology and phytochemistry

OBJECTIVES

Fructus arctii (F. arctii) is the dried ripe fruit of Arctium lappa Willd (Asteraceae). It is being used as a traditional medicine in China, Japan, Iran, Europe, Afghanistan, India, etc. for cough, inflammation, clearing the heat, detoxification, cancer and diabetes. This review summarized the botanical description, distribution, ethnopharmacology, bioactive constituents and pharmacological actions of F. arctii including methods to assess its quality. In addition, this review also provides insights into future research directions on F. arctii to further explore its bioactive constituents, mechanism involved in pharmacological activity, and clinical use including the development of new analytical methods for assessing the quality.

KEY FINDINGS

The comprehensive analysis of the literature revealed that F. arctii contains lignans, volatile oil, flavonoids, sesquiterpenoids, triterpenes, phenolic acids, etc. Experimental studies on various extracts and drug formulations showed that it has antioxidant, antimicrobial, hypoglycaemic, lipid-lowering, anti-inflammatory, analgesic, antiviral, anti-tumour activity, etc.

SUMMARY

The pharmacological activity of a few major constituents in F. arctii have been identified. However, there are still need more studies and more new technologies to prove the pharmacological activity and the effective mechanism of the other constituents that undergoing uncertain. Except for the animal experiments, clinical studies should be carried out to provide the evidence for clinical application.

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.

Substantial effect of phytochemical constituents against the pandemic disease influenza-a review

Background

Influenza is an acute respiratory tract infection caused by the influenza virus. Vaccination and antiviral drugs are the two methods opted to control the disease. Besides their efficiency, they also cause adverse side effects. Hence, scientists turned their attention to powerful herbal medicines. This review put focus on various proven, scientifically validated anti-influenza compounds produced by the plants suggested for the production of newer drugs for the better treatment of influenza and its related antiviral diseases too.

Main body

In this review, fifty medicinal herb phytochemical constituents and their anti-influenza activities have been documented. Specifically, this review brings out the accurate and substantiates mechanisms of action of these constituents. This study categorizes the phytochemical constituents into primary and secondary metabolites which provide a source for synthesizing and developing new drugs.

Conclusion

This article provides a summary of the actions of the herbal constituents. Since the mechanisms of action of the components are elucidated, the pandemic situation arising due to influenza and similar antiviral diseases can be handled promisingly with greater efficiency. However, clinical trials are in great demand. The formulation of usage may be a single drug compound or multi-herbal combination. These, in turn, open up a new arena for the pharmaceutical industries to develop innovative drugs.

Optimisation of the Conversion and Extraction of Arctigenin From Fructus arctii Into Arctiin Using Fungi

Fructus arctii is commonly used in Chinese medicine, and arctiin and arctigenin are its main active ingredients. Arctiin has low bioavailability in the human body and needs to be converted into arctigenin by intestinal microbes before it can be absorbed into the blood. Arctigenin has antiviral, anti-inflammatory, and anti-tumour effects and its development has important value. In this study, we used external microbial fermentation with Aspergillus awamori and Trichoderma reesei to process and convert arctiin from F. arctii powder into arctigenin, hence increasing its bioavailability. We developed a fermentation process by optimising the carbon and nitrogen source/ratio, fermentation time, pH, liquid volume, inoculation volume, and substrate solid-liquid ratio. This allowed for an arctiin conversion rate of 99.84%, and the dissolution rate of the final product was 95.74%, with a loss rate as low as 4.26%. After the fermentation of F. arctii powder, the average yield of arctigenin is 19.51 mg/g. Crude fermented F. arctii extract was purified by silica gel column chromatography, and we observed an arctigenin purity of 99.33%. Our technique effectively converts arctiin and extracts arctigenin from F. arctii and provides a solid basis for further development and industrialisation.

Investigation of Anti-SARS, MERS, and COVID-19 Effect of Jinhua Qinggan Granules Based on a Network Pharmacology and Molecular Docking Approach

Objective

Jinhua Qinggan Granules (JQGs) have achieved certain results in the prevention and treatment of COVID-19 in China during this coronavirus storm. In this study, we aimed to analyze the common mechanisms of JQG in the treatment of coronavirus-induced diseases, such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and COVID-19 via network pharmacology and molecular docking.

Methods

The active compounds of JQG were collected through Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform. The common targets associated with these 3 diseases were screened from GeneCards database. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of JQG’s core targets were analyzed using The Database for Annotation, Visualization, and Integrated Discovery and KOBAS 3.0 system. Further, the protein-protein interaction network was built using STRING database. The compound-target- signaling pathway network was constructed using Cytoscape 3.7.2. The core components of JQG were docked with core targets, COVID-19 coronavirus 3 Cl hydrolase, and angiotensin-converting enzyme 2 (ACE2) via Discovery Studio 2016 software.

Results

A total of 139 active compounds, 50 core targets, and 122 signaling pathways were screened out. The results of molecular docking showed that arctiin and linarin had a higher docking score with 3 Cl, ACE2, and core targets of JQH for antiviral effect.

Conclusion

The potential mechanism of action of JHQ in the treatment of MERS, SARS, and COVID-19 may be associated with the regulation of genes co-expressed with ACE2 and immune- related signaling pathways.

Physical properties of lactic acid bacteria influence the level of protection against influenza infection in mice

We evaluated whether the water dispersibility of lactic acid bacteria (Enterococcus faecalis KH2) affects their efficacy. When cultured lactic acid bacteria are washed, heat-killed, and powdered, adhesion occurs between results in aggregation (non-treated lactic acid bacteria, n-LAB). However, dispersed lactic acid bacteria (d-LAB) with a lower number of aggregates can be prepared by treating them with a high-pressure homogenizer and adding an excipient during powdering. Mice were administered n-LAB or d-LAB Peyer’s patches in the small intestine were observed. Following n-LAB administration, a high amount of aggregated bacteria drifting in the intestinal mucosa was observed; meanwhile, d-LAB reached the Peyer’s patches and was absorbed into them. Evaluation in a mouse influenza virus infection model showed that d-LAB was more effective than n-LAB in the influenza yield of bronchoalveolar lavage fluids on day 3 post-infection and neutralizing antibody titers of sera and influenza virus-specific immunoglobulin A in the feces on day 14 post-infection. Therefore, the physical properties of lactic acid bacteria affect their efficacy; controlling their water dispersibility can improve their effectiveness.

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.

Medicinal Plants, Phytochemicals, and Herbs to Combat Viral Pathogens Including SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome corona virus-2 (SARS-CoV-2), is the most important health issue, internationally. With no specific and effective antiviral therapy for COVID-19, new or repurposed antiviral are urgently needed. Phytochemicals pose a ray of hope for human health during this pandemic, and a great deal of research is concentrated on it. Phytochemicals have been used as antiviral agents against several viruses since they could inhibit several viruses via different mechanisms of direct inhibition either at the viral entry point or the replication stages and via immunomodulation potentials. Recent evidence also suggests that some plants and its components have shown promising antiviral properties against SARS-CoV-2. This review summarizes certain phytochemical agents along with their mode of actions and potential antiviral activities against important viral pathogens. A special focus has been given on medicinal plants and their extracts as well as herbs which have shown promising results to combat SARS-CoV-2 infection and can be useful in treating patients with COVID-19 as alternatives for treatment under phytotherapy approaches during this devastating pandemic situation.

Amino acid-derived defense metabolites from plants: A potential source to facilitate novel antimicrobial development

For millennia, humanity has relied on plants for its medicines, and modern pharmacology continues to reexamine and mine plant metabolites for novel compounds and to guide improvements in biological activity, bioavailability, and chemical stability. The critical problem of antibiotic resistance and increasing exposure to viral and parasitic diseases has spurred renewed interest into drug treatments for infectious diseases. In this context, an urgent revival of natural product discovery is globally underway with special attention directed toward the numerous and chemically diverse plant defensive compounds such as phytoalexins and phytoanticipins that combat herbivores, microbial pathogens, or competing plants. Moreover, advancements in “omics,” chemistry, and heterologous expression systems have facilitated the purification and characterization of plant metabolites and the identification of possible therapeutic targets. In this review, we describe several important amino acid–derived classes of plant defensive compounds, including antimicrobial peptides (e.g., defensins, thionins, and knottins), alkaloids, nonproteogenic amino acids, and phenylpropanoids as potential drug leads, examining their mechanisms of action, therapeutic targets, and structure–function relationships. Given their potent antibacterial, antifungal, antiparasitic, and antiviral properties, which can be superior to existing drugs, phytoalexins and phytoanticipins are an excellent resource to facilitate the rational design and development of antimicrobial drugs.

Anti-Influenza virus effects of Enterococcus faecalis KH2 and Lactobacillus plantarum SNK12 RNA

Bacterial RNA has recently emerged as an immune-stimulating factor during viral infection. The immune response in an organism is directly related to the progression of virus infections. Lactic acid bacteria in particular have anticancer, bioprotective, and antiallergic effects by modulating immunity. Here, we aimed to demonstrate the effect of bacterial RNA on in vitro production of IL-12, a proinflammatory cytokine, and on in vivo activity against influenza A virus (IFV) infection. Oral administration of heat-killed Enterococcus faecalis KH2 (KH2) or Lactobacillus plantarum SNK12 (SNK) in IFV-infected mice suppressed viral replication and stimulated production of virus-specific antibodies. However, ribonuclease-treated KH2 or SNK abrogated the effect, reducing IL-12 production in vitro and anti-IFV effects in vivo. Taken together, KH2 or SNK showed antiviral effects in vivo when administered orally, and the RNAs of KH2 and SNK play a part in these effects, despite the phylogenetic differences between the bacteria.

Arctigenin attenuates CCl4-induced hepatotoxicity through suppressing matrix metalloproteinase-2 and oxidative stress

Background

In spite of the huge advances in recent medicine, there is no effective drug that completely protects the liver from toxic materials. This study was conducted to investigate the hepatoprotective effect of arctigenin from burdock (Arctium lappa) against carbon tetrachloride (CCl4)-induced liver injury.

Results

Arctigenin pre-administration reduced hepatotoxicity markers significantly as compared to CCl4 group. In addition, both silymarin and arctigenin declined matrix metalloproteinase-2 (MMP-2) in the serum (1177 ± 176), (978 ± 135) significantly as compared to CCl4 group (1734 ± 294). The hepatic antioxidant parameters (total glutathione, superoxide dismutase, and glutathione reductase) were significantly decreased after CCl4 injection, an effect that has been prevented by pre-administration of both silymarin and arctigenin. Histological examinations illustrated that arctigenin reduced CCl4 damage, where it decreased inflammation, congestion, and ballooning.

Conclusions

Arctigenin exerted a hepatoprotective effect against CCl4-induced liver damage in terms of suppressing MMP-2 and oxidative stress comparative to that of silymarin.

Antileishmanial Activity of Lignans, Neolignans, and Other Plant Phenols

Secondary metabolites (SM) from organisms have served medicinal chemists over the past two centuries as an almost inexhaustible pool of new drugs, drug-like skeletons, and chemical probes that have been used in the "hunt" for new biologically active molecules with a "beneficial effect on human mind and body." Several secondary metabolites, or their derivatives, have been found to be the answer in the quest to search for new approaches to treat or even eradicate many types of diseases that oppress humanity. A special place among SM is occupied by lignans and neolignans. These phenolic compounds are generated biosynthetically via radical coupling of two phenylpropanoid monomers, and are known for their multitarget activity and low toxicity. The disadvantage of the relatively low specificity of phenylpropanoid-based SM turns into an advantage when structural modifications of these skeletons are made. Indeed, phenylpropanoid-based SM previously have proven to offer great potential as a starting point in drug development. Compounds such as Warfarin^® (a coumarin-based anticoagulant) as well as etoposide and teniposide (podophyllotoxin-based anticancer drugs) are just a few examples. At the beginning of the third decade of the twenty-first century, the call for the treatment of more than a dozen rare or previously "neglected" diseases remains for various reasons unanswered. Leishmaniasis, a neglected disease that desperately needs new ways of treatment, is just one of these. This disease is caused by more than 20 leishmanial parasites that are pathogenic to humans and are spread by as many as 800 sandfly species across subtropical areas of the world. With continuing climate changes, the presence of Leishmania parasites and therefore leishmaniasis, the disease caused by these parasites, is spreading from previous locations to new areas. Thus, leishmaniasis is affecting each year a larger proportion of the world's population. The choice of appropriate leishmaniasis treatment depends on the severity of the disease and its form of manifestation. The success of current drug therapy is often limited, due in most cases to requiring long hospitalization periods (weeks to months) and the toxicity (side effects) of administered drugs, in addition to the increasing resistance of the parasites to treatment. It is thus important to develop new drugs and treatments that are less toxic, can overcome drug resistance, and require shorter periods of treatment. These aspects are especially important for the populations of developing countries. It was reported that several phenylpropanoid-based secondary metabolites manifest interesting antileishmanial activities and are used by various indigenous people to treat leishmaniasis. In this chapter, the authors shed some light on the various biological activities of phenylpropanoid natural products, with the main focus being on their possible applications in the context of antileishmanial treatment.

Aqueous extract of Arctium lappa L. root (burdock) enhances chondrogenesis in human bone marrow-derived mesenchymal stem cells

BACKGROUND

Arctium lappa L. root (burdock root) has long been recommended for the treatment of different diseases in traditional Chinese medicine. Burdock root possesses anti-oxidative, anti-inflammatory, anti-cancer, and anti-microbial activities. The aim of the study was to elucidate whether aqueous extract of burdock root regulates mesenchymal stem cell proliferation and differentiation.

METHODS

Human bone marrow-derived mesenchymal stem cells in 2D high density culture and in 3D micromass pellets were treated with chondrogenic induction medium and chondral basal medium in the absence or presence of aqueous extract of burdock root. The chondrogenic differentiation was accessed by staining glucosaminoglycans, immunostaining SOX9 and type II collagen and immuonblotting of SOX9, aggrecan and type II collagen.

RESULTS

Treatment of aqueous extract of burdock root increased the cell proliferation of hMSCs. It did not have significant effect on osteogenic and adipogenic differentiation, but significantly enhanced chondrogenic induction medium-induced chondrogenesis. The increment was dose dependent, as examined by staining glucosaminoglycans, SOX9, and type II collagen and immunobloting of SOX9, aggrecan and type II collagen in 2D and 3D cultures. In the presence of supplemental materials, burdock root aqueous extract showed equivalent chondrogenic induction capability to that of TGF-β.

CONCLUSIONS

The results demonstrate that aqueous extract of Arctium lappa L. root promotes chondrogenic medium-induced chondrogenic differentiation. The aqueous extract of burdock root can even be used alone to stimulate chondrogenic differentiation. The study suggests that the aqueous extract of burdock root can be used as an alternative strategy for treatment purposes.

Role of Traditional Chinese Medicine in the Management of Viral Pneumonia

Viral pneumonia is one kind of acute respiratory tract infection caused by the virus. There have been many outbreaks of viral pneumonia with high contagiousness and mortality both in China and abroad, such as the great influenza in 1918, the severe acute respiratory syndrome (SARS) coronavirus in 2003, the Influenza A (H1N1) virus in 2009, and the Middle East Respiratory Syndrome coronavirus (MERS-CoV) in 2012 and the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019. These outbreaks and/or pandemic have significant impact on human life, social behaviors, and economic development. Moreover, no specific drug has been developed for these viruses. Traditional Chinese medicine (TCM) plays an important role in the treatment of viral pneumonia during these outbreaks especially in SARS and SARS-CoV-2 because studies suggest that TCM formulations may target several aspects of the disease and may have lesser side effects than manufactured pharmaceuticals. In recent years, a lot of clinicians and researchers have made a series of in-depth explorations and investigations on the treatment of viral pneumonia with TCM, which have understood TCM therapeutic mechanisms more specifically and clearly. But critical analysis of this research in addition to further studies are needed to assess the potential of TCM in the treatment of viral pneumonia.

Antidepressive Effect of Arctiin by Attenuating Neuroinflammation via HMGB1/TLR4- and TNF-α/TNFR1-Mediated NF-κB Activation

Inflammation is a potential factor in the pathophysiology of depression. A traditional Chinese herbal medicine, arctiin, and its aglycone, arctigenin, are the major bioactive components in Fructus arctii and exhibit neuroprotective and anti-inflammatory activities. Arctigenin has been reported to have antidepressant-like effects. However, the antidepressant-like effects of arctiin, its precursor, remain unknown. In this study, we investigated the antidepressant-like effects of arctiin and its underlying mechanisms by in vivo and in vitro experiments in mice. Our results showed that arctiin significantly attenuated sucrose consumption and increased the immobility time in tail suspension and forced swimming tests. Arctiin decreased neuronal damage in the prefrontal cortex (PFC) of the brain. Arctiin also attenuated the levels of three inflammatory mediators, indoleamine 2,3-dioxygenase, 5-hydroxytryptamine, and dopamine, that were elevated in the PFC or serum of chronic unpredictable mild stress (CUMS)-exposed mice. Arctiin reduced excessive activation of microglia and neuroinflammation by reducing high mobility group box 1 (HMGB1)/toll-like receptor 4 (TLR4)- and tumor necrosis factor-α (TNF-α)/TNF receptor 1 (TNFR1)-mediated nuclear factor-kappa B (NF-κB) activation in the PFC of CUMS-exposed mice and HMGB1- or TNF-α-stimulated primary cultured microglia. These findings demonstrate that arctiin ameliorates depression by inhibiting the activation of microglia and inflammation via the HMGB1/TLR4 and TNF-α/TNFR1 signaling pathways.

An integrated strategy for revealing the pharmacological changes based on metabolites profiling and network pharmacology: Arctiin as an example

Traditional Chinese medicine was widely used in China since its definite effects and therapy. The components of TCM were absorbed into the circle system as the format of prototypes or metabolites, which contributed to the therapy or side effects. Declaring the functional changes in this process was of great importance to the clinical applications. In this work, an integrated strategy based on metabolites' profiling and network pharmacology was proposed for exploring the pharmacological changes of compounds in vivo. Arctiin, the main component in Fructus Arctii with various kinds of bioactivities, was used as an example. An ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry and metabolynx™software was applied to characterize the metabolites of arctiin in rats at a dosage of 100 mg/kg; network pharmacology was applied to characterize the functional changes. As a result, fifty-three metabolites (32 in plasma, 40 in urine, 19 in bile, 20 in feces, 1 in brain, 12 in liver and 4 in lungs) were screened out and characterized, and 3 of them were unambitiously identified by comparison with standard substances. Among them, 38 metabolites were reported for the first time. It was found the major metabolic pathways of arctiin in rats were demethylation, lactone-opening and phase II conjugations with sulfate and glucuronide.It also confirmed that M14, M15, M18, M23, M22, M43 and M45 were the major circulating forms of arctiin in rats following oral administration. In addition to the above metabolic reactions, phase I reactions of hydrolysis, demethylation, dehydroxylation were also observed, and dehydrogenation were first revealed metabolic patterns of arctiin in rats. Meanwhile, in addition to the main targets of arctiin (MTOR, EGFR and MAPK14), its metabolites targeted additional 392 targets with additional functions of anti-hepatitis B or viral carcinogenesis (SRC, CAPS3, PIK3CA, CDK4, ESR1, MMP9 and ERBB2). The above results provided very important information for understanding the metabolism and functional changes of arctiinin vivo, and supporting data for further pharmacological evaluation. Our work also provided a newsight for elucidation of functional changes of TCMs in vivo.

Arctigenin inhibits proliferation of ER-positive breast cancer cells through cell cycle arrest mediated by GSK3-dependent cyclin D1 degradation

Estrogen receptor (ER) positive accounts for a large proportion of breast cancer. Although there are many targeted therapeutic drugs, the emergence of drug resistance urgently requires the development of new drugs. Arctigenin (Arc), a lignan found in certain plants of the Asteraceae, has the effect on inhibiting breast cancer, but its molecular mechanism has not been clear.

AIMS

To this end, the current study focuses on understanding the mechanism of Arc on ER-positive breast cancer cells.

MAIN METHODS

Colony formation experiments and sulforhodamine B methods were used to determine the growth-inhibitory effect of Arc. The cell cycle and apoptosis were analyzed by flow cytometry. Alterations of signaling proteins were measured by Western blotting. Protein degradation was determined by comparing protein half-lives and inhibiting proteasome.

KEY FINDINGS

The experimental results show that Arc did not induce apoptosis in ER-positive breast cancer cell, rather caused G1 cycle arrest by decreasing cyclin D1 levels without effect on altering CDK4/6 levels. Moreover, we have demonstrated that Arc decreases cyclin D1 levels through prompting Akt/GSK3β-mediated degradation.

SIGNIFICANCE

These findings warrant the potential of Arc as a candidate treatment for ER-positive breast cancer.

Arctigenin Enhances the Cytotoxic Effect of Doxorubicin in MDA-MB-231 Breast Cancer Cells

Several reports have described the anti-cancer activity of arctigenin, a lignan extracted from Arctium lappa L. Here, we investigated the effect of arctigenin (ATG) on doxorubicin (DOX)-induced cell death using MDA-MB-231 human breast cancer cells. The results showed that DOX-induced cell death was enhanced by ATG/DOX co-treatment in a concentration-dependent manner and that this was associated with increased DOX uptake and the suppression of multidrug resistance-associated protein 1 (MRP1) gene expression in MDA-MB-231 cells. ATG enhanced DOX-induced DNA damage and decreased the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and the expressions of RAD51 and survivin. Cell death caused by ATG/DOX co-treatment was mediated by the nuclear translocation of apoptosis inducing factor (AIF), reductions in cellular and mitochondrial Bcl-2 and Bcl-xL, and increases in mitochondrial BAX levels. However, caspase-3 and -7 did not participate in DOX/ATG-induced cell death. We also found that DOX/ATG-induced cell death was linked with activation of the p38 signaling pathway and suppressions of the phosphorylations and expressions of Akt and c-Jun N-terminal kinase. Taken together, these results show that ATG enhances the cytotoxic activity of DOX in MDA-MB-231 human breast cancer cells by inducing prolonged p21 expression and p38-mediated AIF-dependent cell death. In conclusion, our findings suggest that ATG might alleviate the side effects and improve the therapeutic efficacy of DOX.

Anti‑metastatic effects of arctigenin are regulated by MAPK/AP‑1 signaling in 4T‑1 mouse breast cancer cells

Arctigenin is a natural lignan that is found in burdock with anti‑viral, ‑oxidative, ‑inflammatory and anti‑tumor activities. In the current study, the effect of arctigenin on metastatic potential was examined in 4T‑1 mouse triple‑negative breast cancer cells. The results indicated that arctigenin inhibited cell motility and invasiveness, which was determined using wound healing and transwell invasion assays. Arctigenin suppressed matrix metalloprotease‑9 (MMP‑9) activity via gelatin zymography, and protein expression of cyclooxygenase‑2 (COX‑2) and MMP‑3. Furthermore, arctigenin attenuated the mRNA expression of metastatic factors, including MMP‑9, MMP‑3 and COX‑2. Based on these results, the effect of arctigenin on the mitogen‑activated protein kinase (MAPK)/activating protein‑1 (AP‑1) signaling pathway was assessed in an attempt to identify the regulatory mechanism responsible for its anti‑metastatic effects. Arctigenin was demonstrated to inhibit the phosphorylation of extracellular signal‑regulated protein kinase (ERK) and c‑Jun N‑terminal kinase (JNK), and the nuclear translocations of the AP‑1 subunits, c‑Jun and c‑Fos. In summary, the present study demonstrated that in 4T‑1 mouse triple‑negative breast cancer cells the anti‑metastatic effect of arctigenin is mediated by the inhibition of MMP‑9 activity and by the inhibition of the metastasis‑enhancing factors MMP‑9, MMP‑3 and COX‑2, due to the suppression of the MAPK/AP‑1 signaling pathway. The results of the current study demonstrated that arctigenin exhibits a potential for preventing cell migration and invasion in triple negative breast cancer.

Lignans and Their Derivatives from Plants as Antivirals

Lignans are widely produced by various plant species; they are a class of natural products that share structural similarity. They usually contain a core scaffold that is formed by two or more phenylpropanoid units. Lignans possess diverse pharmacological properties, including their antiviral activities that have been reported in recent years. This review discusses the distribution of lignans in nature according to their structural classification, and it provides a comprehensive summary of their antiviral activities. Among them, two types of antiviral lignans—podophyllotoxin and bicyclol, which are used to treat venereal warts and chronic hepatitis B (CHB) in clinical, serve as examples of using lignans for antivirals—are discussed in some detail. Prospects of lignans in antiviral drug discovery are also discussed.

Evaluation of potential herb-drug interactions between oseltamivir and commonly used anti-influenza Chinese medicinal herbs

ETHNOPHARMACOLOGICAL RELEVANCE

According to Traditional Chinese Medicine theory, influenza is categorized as a warm disease or Wen Bing. The Wen Bing formulas, such as Yin-Qiao-San and Sang-Ju-Yin, are still first-line herbal therapies in combating variant influenza virus. To continue our study on the pharmacokinetic and pharmacodynamic interactions between Wen Bing formulas and oseltamivir (OS), the first-line western drug for the treatment of influenza, further interactions between OS and the eight single herbs and their relevant marker components from Wen Bing formulas were investigated in the current study.

AIM OF STUDY

To establish an in-vitro screening platform for investigation of the potential anti-influenza herbs/herbal components that may have pharmacokinetic and pharmacodynamic interactions with OS.

MATERIALS AND METHODS

To screen potential inhibition on OS hydrolysis, 1 μg/mL of OS is incubated with herbs/herbal components in diluted rat plasma, microsomes and human recombinant carboxylesterase 1(hCE1) under optimized conditions. MDCK-WT and MDCK-MDR1 cell lines are utilized to identify potential modification on P-gp mediated transport of OS by herbs/herbal components. Caco-2 cells with and without Gly-Sar inhibition are performed to study the uptake of OS via PEPT1 transporters. Modification on OAT3 mediated transport is verified by the uptake of OS on HEK293-MOCK/HEK293-OAT3 cells. Anti-virus effects were evaluated using plaque reduction assay on H1N1 and H3N2 viruses. Potential pharmacokinetic and pharmacodynamic interaction between OS (30 mg/kg) and the selected herb, Radix Scutellariae (RS), at 300-600 mg/kg were carried out on rats. All samples are analyzed by an LC/MS/MS method for the contents of OS and OSA. A mechanistic PK model was developed to interpret the HDI between OS and RS in rats.

RESULTS

Our developed platform was successfully applied to screen the eight herbal extracts and their ten marker components on metabolic inhibition of OS and modification of OS transport mediated by P-gp, OAT3 and PEPT1. Results from six in-vitro experiments were analyzed after converting raw data from each experiment to corresponding fold-change (FC) values, based on which Radix Scutellariae (RS) were selected to have the most HDI potential with OS. By analyzing the plasma and urine pharmacokinetic data after co-administration of OS with a standardized RS extract in rats using an integrated population pharmacokinetics model, it is suggested that RS could inhibit OS hydrolysis during absorption and increase the absorbed fraction of OS, which leads to the increased ratio of OS concentration versus that of OSA in both rat plasma and urine. Never the less, the anti-virus effects of 2.5 h post-dose rat plasma were not influenced by co-administration of OS with RS.

CONCLUSION

A six-dimension in-vitro screening platform has been developed and successfully applied to find RS as a potential herb that would influence the co-administrated OS in rats. Although co-administered RS could inhibit OS hydrolysis during absorption and increase the absorbed fraction of OS, which lead to the increased ratio of OS concentration versus that of OSA in both rat plasma and urine, the anti-virus effect of OS was not influenced by co-administered RS.

Activation of reactive oxygen species-mediated mitogen-activated protein kinases pathway regulates both extrinsic and intrinsic apoptosis induced by arctigenin in Hep G2

OBJECTIVES

Arctigenin (ARG) has been proved to inhibit the viability of hepatocellular carcinoma (HCC) via inducing apoptosis. However, the precise mechanism remains unknown. The present study was aimed to further investigate the mechanism of ARG against HCC in vitro and in vivo.

METHODS

Arctigenin was applied in vitro and in vivo. Western blotting, immunohistochemistry, etc., were used to investigate the mechanisms.

KEY FINDINGS

The time-dependent enhancement of Bax/Bcl-2 ratio, cytochrome c release, Fas and FasL levels, caspase cascade activation and the loss in the mitochondrial out membrane potential indicated that both intrinsic and extrinsic apoptotic pathways were triggered by ARG. Moreover, Jun NH2-terminal kinase (JNK) and p38 phosphorylated time-dependently. And inhibition of the phosphorylation of either p38 or JNK led to a significant reduction in HepG2 apoptosis, owing to the crucial roles of p38 and JNK played in regulating the apoptosis pathways. In addition, ARG increased the generation of reactive oxygen species (ROS) in HepG2 cells, while the antioxidant N-acetyl cysteine almost reversed ARG-induced JNK and p38 activation, and dramatically decreased cell apoptosis. In vivo, ARG increased the cell apoptosis in tumour tissues, and p-p38, p-JNK and Bax were significantly upregulated.

CONCLUSIONS

Our findings demonstrated that ARG induced apoptosis in HCC via ROS-mediated mitogen-activated protein kinases apoptosis pathway.

Synthesis and antiviral activity of a new arctigenin derivative against IHNV in vitro and in vivo

Viral diseases in aquaculture were challenging because there are few preventative measures and/or treatments. Our previous study indicated that imidazole arctigenin derivatives possessed antiviral activities against infectious hematopoietic necrosis virus (IHNV). Based on the structure-activity relationship in that study, a new imidazole arctigenin derivative, 4-(8-(2-ethylimidazole)octyloxy)-arctigenin (EOA), was designed, synthesized and its anti-IHNV activity was evaluated. By comparing inhibitory concentration at half-maximal activity (IC₅₀), we found that EOA (IC₅₀ = 0.56 mg/L) possessed a higher antiviral activity than those imidazole arctigenin derivatives in our previous study. Besides, EOA could significantly decrease cytopathic effect (CPE) and viral titer induced by IHNV in epithelioma papulosum cyprinid (EPC) cells. In addition, EOA significantly inhibited apoptosis induced by IHNV in EPC cells. Further data verified that EOA inhibited IHNV replication in rainbow trout, with reducing 32.0% mortality of IHNV-infected fish. The results suggested that EOA was more stable with a prolonged inhibitory half-life in the early stage of virus infection (1-4 days). Consistent with above results, EOA repressed IHNV glycoprotein gene expression in virus sensitive tissues (kidney and spleen) in the early stage of virus infection. Moreover, histopathological evaluation showed that tissues from the spleen and kidney of fish infected with IHNV exhibited pathological changes. But there were no lesions in any of the tissues from the control group and EOA-treaten group. In accordance with the histopathological assay, EOA could elicited anti-inflammation response in non-viral infected rainbow trout by down-regulating the expression of cytokine genes (IL-8, IL-12p40, and TNF-α). Altogether, EOA was expected to be a therapeutic agent against IHNV infection in the field of aquaculture.

3'-Desmethylarctigenin induces G2/M cell cycle arrest and apoptosis through reactive oxygen species generation in hepatocarcinoma cells

Previous studies have shown that arctigenin is a promising chemopreventive or therapeutic agent against various cancers. However, less is known about anticancer activity of 3'-desmethylarctigenin (3'-DMAG), which is a biotransformed product from arctigenin or arctin. In this study, we compared the anticancer activity of 3'-DMAG with its parent compound arctigenin and demonstrated that 3'-DMAG exerted a more potent inhibitory effect on HepG2 cells than arctigenin. Mechanistically, reactive oxygen species generation played an apical role in 3'-DMAG-induced G2/M cell cycle arrest and apoptosis in HepG2 cells. Furthermore, the Chk2-Cdc25c-Cdc2-cyclin B1 cascade was found to contribute to the cell cycle arrest, whereas the activation of mitochondrial pathway was involved in the cell apoptosis by 3'-DMAG. Additionally, a mouse xenograft hepatocellular carcinoma model was used to evaluate the antitumor effect of 3'-DMAG in vivo, and the results indicated that 3'-DMAG treatment significantly inhibited tumor growth without apparent toxicity. Taken together, 3'-DMAG is highly effective against liver cancer both in vitro and in vivo. The findings of the present study suggest that this compound deserves to be further investigated for its potential anticancer activity.

Arctigenin induces apoptosis in human hepatoblastoma cells

PURPOSE

Arctigenin has been shown to have anti-tumor effects in various types of cancers. This study was conducted to verify these effects in the human-derived hepatoblastoma cell line, HUH-6 clone 5 (hereinafter, HUH-6).

METHODS

Arctigenin was added to cultured HUH-6 cells, and cellular activity was evaluated by MTS assay. To determine the relationship between reduced cellular activity and apoptosis, we measured the activities of caspase 3/7, 8, and 9 and conducted flow cytometry with Annexin V/PI staining.

RESULTS

The MTS assay revealed that cellular activity decreased after arctigenin treatment in a concentration-dependent manner (IC₅₀ = 4 µM). To investigate apoptosis induction, activity assays of caspase 3/7, 8, and 9 were performed. While caspase 3/7 and 8 exhibited high activity, caspase 9 showed no activity. Thus, apoptosis induction may have involved the action of tumor necrosis factor receptor 1 (TNFR1). Flow cytometry conducted with Annexin V/PI staining revealed the occurrence of early apoptosis.

CONCLUSION

We found that arctigenin has anti-tumor effects in HUH-6 cells in a concentration-dependent manner. Arctigenin may have exerted its anti-tumor effect by inducing apoptosis via TNFR1, which recruits Complex IIa to activate caspase 8 and 3/7. These results may be useful for developing therapeutic agents for hepatoblastoma.

Lignans and Neolignans: Plant secondary metabolites as a reservoir of biologically active substances

Lignans and neolignans are plant secondary metabolites derived from the oxidative coupling of phenylpropanoids. Biological activity of these phenolic compounds ranges from antioxidant, antitumor (terminaloside P, IC₅₀ = 10 nM), anti-inflammatory, anti-neurodegenerative (schibitubin B, IC₅₀ = 3.2 nM) and antiviral (patentiflorin A, IC₅₀ = 14-23 nM) to antimicrobial. In addition, it was observed that several members of this group, namely enterolactone and its biochemical precursors also known as phytoestrogens, possess important protective properties. Most of these lignans and neolignans are presented in reasonable amounts in one's diet and thus the protection they provide against the colon and breast cancer, to name a few, is even more important to note. Similarly, neuroprotective properties were observed (schisanwilsonin G, IC₅₀ = 3.2 nM) These structural motives also serve as an important starting point in the development of anticancer drugs. Presumably the most famous members of this family, etoposide and teniposide, synthetic derivatives of podophyllotoxin, are used in the clinical treatment of lymphocytic leukemia, certain brain tumors, and lung tumors already for nearly 20 years. This review describes 413 lignans and neolignans which have been isolated between 2016 and mid-2018 being reported in more than 300 peer-reviewed articles. It covers their source, structure elucidation, and bioactivity. Within the review, the structure-based overview of compounds as well as the bioactivity-based overview of compounds are described.

Synthesis and Characterization of a Silica-Based Drug Delivery System for Spinal Cord Injury Therapy

Acute inflammation is a central component in the progression of spinal cord injury (SCI). Anti-inflammatory drugs used in the clinic are often administered systemically at high doses, which can paradoxically increase inflammation and result in drug toxicity. A cluster-like mesoporous silica/arctigenin/CAQK composite (MSN-FC@ARC-G) drug delivery system was designed to avoid systemic side effects of high-dose therapy by enabling site-specific drug delivery to the spinal cord. In this nanosystem, mesoporous silica was modified with the FITC fluorescent molecule and CAQK peptides that target brain injury and SCI sites. The size of the nanocarrier was kept at approximately 100 nm to enable penetration of the blood-brain barrier. Arctigenin, a Chinese herbal medicine, was loaded into the nanosystem to reduce inflammation. The in vivo results showed that MSN-FC@ARC-G could attenuate inflammation at the injury site. Behavior and morphology experiments suggested that MSN-FC@ARC-G could diminish local microenvironment damage, especially reducing the expression of interleukin-17 (IL-17) and IL-17-related inflammatory factors, inhibiting the activation of astrocytes, thus protecting neurons and accelerating the recovery of SCI. Our study demonstrated that this novel, silica-based drug delivery system has promising potential for clinical application in SCI therapy.