Indirubin, a bisindole alkaloid from Isatis indigotica, reduces H1N1 susceptibility in stressed mice by regulating MAVS signaling

Indigo Naturalis in Inflammatory Bowel Disease: mechanisms of action and insights from clinical trials

This study investigates the therapeutic potential of Indigo Naturalis (IN) in treating a Inflammatory Bowel Disease (IBD). The objective is to comprehensively examine the effects and pharmacological mechanisms of IN on IBD, assessing its potential as an novel treatment for IBD. Analysis of 11 selected papers is conducted to understand the effects of IN, focusing on compounds like indirubin, isatin, indigo, and tryptanthrin. This study evaluates their impact on Disease Activity Index (DAI) score, colon length, mucosal damage, and macrophage infiltration in Dextran Sulfate Sodium (DSS)-induced colitis mice. Additionally, It investigate into the anti-inflammatory mechanisms, including Aryl hydrocarbon Receptor (AhR) pathway activation, Nuclear Factor kappa B (NF-κB)/nod-like receptor family pyrin domain containing 3 (NLRP3)/Interleukin 1 beta (IL-1β) inhibition, and modulation of Toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MYD88)/NF-κB and Mitogen Activated Protein Kinase (MAPK) pathways. Immunomodulatory effects on T helper 17 (Th17)/regulatory T cell (Treg cell) balance and Glycogen synthase kinase-3 beta (GSK3-β) expression are also explored. Furthermore, the study addresses the role of IN in restoring intestinal microbiota diversity, reducing pathogenic bacteria, and increasing beneficial bacteria. The findings reveal that IN, particularly indirubin and indigo, demonstrates significant improvements in DAI score, colon length, mucosal damage, and macrophage infiltration in DSS-induced colitis mice. The anti-inflammatory effects are attributed to the activation of the AhR pathway, inhibition of inflammatory pathways, and modulation of immune responses. These results exhibit the potential of IN in IBD treatment. Notably, the restoration of intestinal microbiota diversity and balance further supports its efficacy. IN emerges as a promising and effective treatment for IBD, demonstrating anti-inflammatory effects and positive outcomes in preclinical studies. However, potential side effects necessitate further investigation for safe therapeutic development. The study underscores the need for future research to explore a broader range of active ingredients in IN to enhance therapeutic efficacy and safety.

STK214947, a novel indole alkaloids, inhibits HeLa and SK-HEP-1 cells survival and EMT process by blocking the Notch3 and Akt signals

Apoptosis and epithelial-to-mesenchymal transition (EMT) are closely associated with tumor survival and metastasis. These are the basic events in tumor occurrence and progression. STK214947 is an indole alkaloid with a skeleton that is similar to that of indirubin. Indole alkaloids have attracted considerable attention because of their antitumor activity. However, the relationship between STK214947 and these basic events remains unknown. In this study, the effects of STK214947 on inducing apoptosis and reversing the EMT process in tumor cells were confirmed. Mild concentrations of STK214947 inhibited tumor cell migration by reversing EMT and significantly regulated the expression of EMT-related proteins, including Notch3, E-cadherin, N-cadherin and vimentin. In addition, STK214947 in high concentration could induce apoptosis by down-regulating Notch3, p-Akt/Akt, and NF-κB, and upregulating Caspase 3. These findings support the further development of STK214947 as a potential antitumor small molecule that targets Notch3 and Akt signal transduction in cancer.

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.

Indigo production goes green: a review on opportunities and challenges of fermentative production

Indigo is a widely used dye in various industries, such as textile, cosmetics, and food. However, traditional methods of indigo extraction and processing are associated with environmental and economic challenges. Fermentative production of indigo using microbial strains has emerged as a promising alternative that offers sustainability and cost-effectiveness. This review article provides a critical overview of microbial diversity, metabolic pathways, fermentation strategies, and genetic engineering approaches for fermentative indigo production. The advantages and limitations of different indigo production systems and a critique of the current understanding of indigo biosynthesis are discussed. Finally, the potential application of indigo in other sectors is also discussed. Overall, fermentative production of indigo offers a sustainable and bio-based alternative to synthetic methods and has the potential to contribute to the development of sustainable and circular biomanufacturing.

Identification of novel flavin-dependent monooxygenase from Strobilanthes Cusia reveals molecular basis of indoles' biosynthetic logic

BACKGROUND

Strobilanthes cusia (Nees) Kuntze is a traditional medical plant distributed widely in south China. The indole compounds that originated from the plant are responsible for its pharmacological activities. However, the reason why indole ingredients are accumulated in this herb and how it is biosynthesized has remained largely unknown.

RESULTS

In this study, metabolic and transcriptional profiling measurement experiments of different S. cusia organs were carried out to understand the underlying molecular basis of indoles' biosynthetic logic. A metabolic investigation demonstrated that the indoles are primarily accumulated mainly in aerial parts, particularly in leaves. RNA-seq was employed to reveal the organ specific accumulation of indoles in different S. cusia organs. Meanwhile, a flavin-dependent monooxygenase gene (ScFMO1) was found in S. cusia, and it has capacity to produce indoxyl from indole by the fermentation assay. Finally, we assessed the outcomes of transient expression experiment in tobacco and confirmed that ScFMO1 localizes in cytoplasm.

CONCLUSIONS

Our results suggest that ScFMO1 plays a key role in biosynthesis of indoles (Indigo, indirubin, indican, etc.), it will be useful for illuminating the molecular basis of the medicinal indoles' biosynthesis and developing strategies for improving their yields.

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.

Modulation of type I interferon signaling by natural products in the treatment of immune-related diseases

Type I interferon (IFN) is considered as a bridge between innate and adaptive immunity. Proper activation or inhibition of type I IFN signaling is essential for host defense against pathogen invasion, tumor cell proliferation, and overactive immune responses. Due to intricate and diverse chemical structures, natural products and their derivatives have become an invaluable source inspiring innovative drug discovery. In addition, some natural products have been applied in clinical practice for infection, cancer, and autoimmunity over thousands of years and their promising curative effects and safety have been well-accepted. However, whether these natural products are primarily targeting type I IFN signaling and specific molecular targets involved are not fully elucidated. In the current review, we thoroughly summarize recent advances in the pharmacology researches of natural products for their type I IFN activity, including both agonism/activation and antagonism/inhibition, and their potential application as therapies. Furthermore, the source and chemical nature of natural products with type I IFN activity are highlighted and their specific molecular targets in the type I IFN pathway and mode of action are classified. In conclusion, natural products possessing type I IFN activity represent promising therapeutic strategies and have a bright prospect in the treatment of infection, cancer, and autoimmune diseases.

Medicinal plants with anti-SARS-CoV activity repurposing for treatment of COVID-19 infection: A systematic review and meta-analysis

The novel SARS-CoV-2 (severe acute respiratory syndrome coronavirus) has emerged as a significant threat to public health with startling drawbacks in all sectors globally. This study investigates the practicality of some medicinal plants for SARS-CoV-2 therapy using a systematic review and meta-analysis of their reported SARS-CoV-1 inhibitory potencies. Relevant data were systematically gathered from three databases, viz., Web of Science, PubMed and Scopus. The information obtained included botanical information, extraction method and extracts concentrations, as well as the proposed mechanisms. Fourteen articles describing 30 different plants met our eligibility criteria. Random effects model and subgroup analysis were applied to investigate heterogeneity. According to subgroup analysis, the substantial heterogeneity of the estimated mean based on the IC ₅₀ values reporting the most potent anti-SARS-CoV 3C--like protease (3CLpro) inhibitors (10.07 %, p < 0.0001), was significantly higher compared to the most active anti-SARS-CoV papain-like protease (PLpro) inhibitors (6.12 %, p < 0.0001). More importantly, the literature analysis revealed that fruit extracts of Rheum palmatum L. and the compound cryptotanshinone isolated from the root of Salvia miltiorrhiza (IC ₅₀ = 0.8 ± 0.2 μmol L^-1) were excellent candidates for anti--SARS-CoV targeting PLpro. Meanwhile, iguesterin (IC ₅₀ = 2.6 ± 0.6 μmol L^-1) isolated from the bark of Tripterygium regelii emerged as the most excellent candidate for anti-SARS--CoV targeting 3CLpro. The present systematic review and meta-analysis provide valuable and comprehensive information about potential medicinal plants for SARS-CoV-2 inhibition. The chemotypes identified herein can be adopted as a starting point for developing new drugs to contain the novel virus.

Potential therapeutic effect of Shufeng Jiedu capsule and its major herbs on coronavirus disease 2019 (COVID-19): A review

The outbreak and rapid spread of coronavirus disease 2019 (COVID-19) poses a huge threat to human health and social stability. Shufeng Jiedu capsule (SFJDC), a patented herbal drug composed of eight medicinal plants, is used to treat different viral respiratory tract infectious diseases. Based on its antiviral, anti-inflammatory, and immunoregulatory activities in acute lung injury, SFJDC can be effectively used as a treatment for COVID-19 patients according to the diagnosis and treatment plan issued in China and existing clinical data. SFJDC has been recommended in 15 therapeutic regimens for COVID-19 in China. This review summarizes current data on the ingredients, chemical composition, pharmacological properties, clinical efficacy, and potential therapeutic effect of SFJDC on COVID-19, to provide a theoretical basis for its anti-viral mechanism and the clinical treatment of COVID-19.

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.

Identification of key gene networks controlling vernalization development characteristics of Isatis indigotica by full-length transcriptomes and gene expression profiles

Isatis indigotica Fort., as a common Chinese medicinal raw material, will lose its medicinal value if it blooms early, so it is highly valuable to clarify the induction mechanism of the vernalization of I. indigotica at low temperature. In this study, the concentrations of soluble sugar, proline, glutathione and zeatin in two germplasms of I. indigotica with different degrees of low temperature tolerance (Y1 and Y2) were determined at 10 days, 20 days and 30 days of low-temperature treatment, and the full-length transcriptome of 24 samples was sequenced by Nanopore sequencing with Oxford Nanopore Technologies (ONT). After that, the data of transcripts involved in the vernalization of I. indigotica at low temperature were obtained, and these transcripts were identified using weighted gene co-expression network analysis (WGCNA). The results revealed the massive accumulation of soluble sugar and proline in Y1 and Y2 after low temperature induction. A total of 18,385 new transcripts, 6168 transcription factors and 470 lncRNAs were obtained. Differential expression analysis showed that gibberellin, flavonoids, fatty acids and some processes related to low temperature response were significantly enriched. Eight key transcripts were identified by WGCNA, among which ONT.14640.1, ONT.9119.1, ONT.13080.2 and ONT.16007.1 encodes a flavonoid transporter, 9-cis-epoxycarotenoid dioxygenase 3 (NCED3), growth factor gene and L-aspartate oxidase in plants, respectively. It indicated that secondary metabolites such as hormones and flavonoids play an important role in the vernalization of I. indigotica. qRT-PCR proved the reliability of transcriptome results. These results provide important insights on the low-temperature vernalization of I. indigotica, and provide a research basis for analyzing the vernalization mechanism of I. indigotica.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12298-021-01110-2.

Glucosinolates and Isothiocyantes in Processed Rapeseed Determined by HPLC-DAD-qTOF

Glucosinolates are well known as natural antimicrobials and anticarcinogenic agents. However, these compounds can lose their properties and transform into antinutrients, depending on processing conditions. In addition, the bitterness of some glucosinolate in rapeseed meal can affect the likability of the final product. Therefore, it is important to identify and determine each glucosinolate and its derived form, not just the total glucosinolate content, in order to evaluate the potential of the final rapeseed protein product. This study provides a comprehensive report of the types and quantities of glucosinolates and their derived forms (isothiocyanates) associated with different rapeseed processing conditions. Glucosinolates and isothiocyanates were determined by HPLC-DAD-qTOF. In our study, the enzymatic degradation of glucosinolates by myrosinase was the main factor affecting either glucosinolate or isothiocyanate content. Other factors such as pH seemed to influence the concentration and the presence of glucosinolates. In addition, process parameters, such as extraction time and separation technology, seemed to affect the amount and type of isothiocyanates in the final protein extracts. Overall, both determined intact glucosinolates and their derived forms of isothiocyanates can give different types of biological effects. More studies should be performed to evaluate the impact of glucosinolates and isothiocyanates on human health.

5-Hydroxymethylfurfural Enhances the Antiviral Immune Response in Macrophages through the Modulation of RIG-I-Mediated Interferon Production and the JAK/STAT Signaling Pathway

5-Hydroxymethylfurfural (5-HMF) exists in a wide range of sugar-rich foods and traditional Chinese medicines. The role of 5-HMF in antiviral innate immunity and its mechanism have not been reported previously. In this study, we reveal for the first time that 5-HMF upregulates the production of retinoic acid-inducible gene I (RIG-I)-mediated type I interferon (IFN) as a response to viral infection. IFN-β and IFN-stimulated chemokine gene expressions induced by the vesicular stomatitis virus (VSV) are upregulated in RAW264.7 cells and primary peritoneal macrophages after treatment with 5-HMF, a natural product that appears to inhibit the efficiency of viral replication. Meanwhile, 5-HMF-pretreated mice show enhanced innate antiviral immunity, increased serum levels of IFN-β, and reduced morbidity and viral loads upon infection with VSV. Thus, 5-HMF can be seen to have a positive effect on enhancing type I IFN production. Mechanistically, 5-HMF upregulates the expression of RIG-I in macrophages, resulting in an acceleration of the RIG-I signaling pathway activation. Additionally, STAT1 and STAT2 phosphorylations, along with the expression of IFN-stimulated chemokine genes induced by IFN-α/β, were also enhanced in macrophages cotreated with 5-HMF. In summary, these findings indicate that 5-HMF not only can induce type I IFN production but also can enhance IFN-JAK/STAT signaling, leading to a novel immunomodulatory mechanism against viral infection. In conclusion, our study reveals a previously unrecognized effect of 5-HMF in the antiviral innate immune response and suggests new potential of utilizing 5-HMF for controlling viral infection.

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.

Indole-3-carboxaldehyde regulates RSV-induced inflammatory response in RAW264.7 cells by moderate inhibition of the TLR7 signaling pathway

Human respiratory syncytial virus (RSV) is highly contagious and the leading cause of severe respiratory tract illness in infants, elderly, and immunocompromised individuals. Toll-like receptor 7 (TLR7), a pattern recognition receptor recognising the ssRNA of RSV, activates proinflammatory pathways and triggers secretion of interferons (IFNs). On the one hand, the inflammatory responses help clear out virus. On the other hand, they lead to severe lung damage. Banlangen is a traditional Chinese herbal medicine commonly prescribed for respiratory virus infection treatment, but the mechanisms of action and active components remain largely unknown. In the present study, we investigated the effects of the main active components of total alkaloids from banlangen (epigoitrin, indole-3-carboxaldehyde, indole-3-acetonitrile and 4-methoxyindole-3-acetonitrile) on the RSV-induced inflammatory responses in mouse macrophage cells (RAW264.7). Our results demonstrated that RSV-induced IFN-α excessive secretion was moderately inhibited by indole-3-carboxaldehyde through downregulation of mRNA expression in a dose-dependent manner, in comparison, the inhibitory effects of ribavirin were too strong. Furthermore, we revealed that indole-3-carboxaldehyde suppressed transcription of IFN-α by inhibiting RSV-induced TLR7 expression in RAW264.7 cells. Additionally, indole-3-carboxaldehyde inhibited RSV-induced NF-κB signalling activation in a TLR7-MyD88-dependent manner. Together, our findings suggest that indole-3-carboxaldehyde inhibited RSV-induced inflammatory injury by moderate regulation of TLR7 signaling pathway and did not significantly affect the viral clearance competence of the innate immune system.

Strobilanthes cusia (Nees) Kuntze, a multifunctional traditional Chinese medicinal plant, and its herbal medicines: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Strobilanthes cusia (Nees) Kuntze (SCK, Malan), a traditional Chinese medicinal plant, has long applied to detoxification, defervescence, detumescence and antiphlogosis. "Southern Banlangen" (Rhizoma et Radix Baphicacanthis Cusiae, RRBC), root and rhizome of SCK, is widely used for treatment of many epidemic diseases. Malanye (Southern Daqingye), stem and leaf of SCK, is an antipyretic-alexipharmic drug frequently-used in southern China. Qingdai (Indigo Naturalis, IN), a processed product of SCK, is always applied to dermatoses in the folk.

AIM OF THE REVIEW

In order to elucidate the historical uses, recent advances and pharmaceutical prospects of SCK, we summarized roundly in aspects of history, processing method, chemical constitution, quality control, pharmacological activity and toxicity. Some deficiencies in current studies and research directions in the future are also discussed. This is the first comprehensive review of SCK and its herbal medicines, which may be of some help for further research.

METHODOLOGY

Comprehensive analysis was conducted on the basis of academic papers, pharmaceutical monographs, ancient medicinal works, and drug standards of China. All available information on SCK and its herbal medicines was collected by using the keywords such as "Strobilanthes cusia", "Southern Banlangen", "indirubin", "tryptanthrin" through different electronic databases including NCBI Pubmed, Google Scholar, Chinese National Knowledge Infrastructure and so on. Pharmacopoeia of China and some ancient works were obtained from National Digital Library of China.

RESULT

Medicinal uses of SCK were already described by famous ancient researchers. Because of vague description, plant species in some works cannot be confirmed. Literature demonstrated that multiple components including total 36 alkaloids and 35 glycosides, the main bioactive components of SCK, were found in SCK and its herbal medicines. Modern studies indicated that SCK and some of its components had multiple pharmacological effects including resistance to cancer, remission of inflammation, suppression of microorganisms, relief of dermatoses, and so on. However, studies on pharmacology, pharmacokinetics, and quality control are still not enough.

CONCLUSION

A number of reports suggested that SCK and its processed medicines could be promising drug candidates for multiple diseases especially promyelocytic leukemia, ulcerative colitis (UC) and psoriasis. However, bioactive activities of most components, especially glycosides should still be explored further. It is crucial to elucidate the in-depth molecular mechanisms, and pharmacokinetic characteristics of main components in those herbal medicines. Moreover, to ensure the effectiveness of clinical medication, future studies should undoubtedly give the priority to clarifying the effective compositions of SCK, and then a measurement standard of those indicators should be protocolled to establish a comprehensive quality evaluation mode.

High-Quality Genome of the Medicinal Plant Strobilanthes cusia Provides Insights Into the Biosynthesis of Indole Alkaloids

Strobilanthes cusia (Nees) Kuntze is an important plant used to process the traditional Chinese herbal medicines "Qingdai" and "Nanbanlangen". The key active ingredients are indole alkaloids (IAs) that exert antibacterial, antiviral, and antitumor pharmacological activities and serve as natural dyes. We assembled the S. cusia genome at the chromosome level through combined PacBio circular consensus sequencing (CCS) and Hi-C sequencing data. Hi-C data revealed a draft genome size of 913.74 Mb, with 904.18 Mb contigs anchored into 16 pseudo-chromosomes. Contig N50 and scaffold N50 were 35.59 and 68.44 Mb, respectively. Of the 32,974 predicted protein-coding genes, 96.52% were functionally annotated in public databases. We predicted 675.66 Mb repetitive sequences, 47.08% of sequences were long terminal repeat (LTR) retrotransposons. Moreover, 983 Strobilanthes-specific genes (SSGs) were identified for the first time, accounting for ~2.98% of all protein-coding genes. Further, 245 putative centromeric and 29 putative telomeric fragments were identified. The transcriptome analysis identified 2,975 differentially expressed genes (DEGs) enriched in phenylpropanoid, flavonoid, and triterpenoid biosynthesis. This systematic characterization of key enzyme-coding genes associated with the IA pathway and basic helix-loop-helix (bHLH) transcription factor family formed a network from the shikimate pathway to the indole alkaloid synthesis pathway in S. cusia. The high-quality S. cusia genome presented herein is an essential resource for the traditional Chinese medicine genomics studies and understanding the genetic underpinning of IA biosynthesis.

From natural dye to herbal medicine: a systematic review of chemical constituents, pharmacological effects and clinical applications of indigo naturalis

Background

Indigo naturalis is a blue dye in ancient, as well as an extensive used traditional Chinese medicine. It has a wide spectrum of pharmacological properties and can be used to treat numerous ailments such as leukemia, psoriasis, and ulcerative colitis. This article aims to expand our understanding of indigo naturalis in terms of its chemical constituents, pharmacological action and clinical applications.

Methods

We searched PubMed, web of science, CNKI, Google academic, Elsevier and other databases with the key words of “Indigo naturalis”, and reviewed and sorted out the modern research of indigo naturalis based on our research results.

Results

We outlined the traditional manufacturing process, chemical composition and quality control of indigo naturalis, systematically reviewed traditional applictions, pharmacological activities and mechanism of indigo naturalis, and summarized its clinical trials about treatment of psoriasis, leukemia and ulcerative colitis.

Conclusions

Indigo naturalis has a variety of pharmacological activities, such as anti-inflammatory, antioxidant, antibacterial, antiviral, immunomodulatory and so on. It has very good clinical effect on psoriasis, leukemia and ulcerative colitis. However, it should be noted that long-term use of indigo naturalis may produce some reversible adverse reactions. In summarize, indigo naturalis is an extremely important drug with great value and potential.

Stereoselective pharmacokinetic study of epiprogoitrin and progoitrin in rats with UHPLC-MS/MS method

An accurate and precise liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method was developed and validated for the pharmacokinetic study of epiprogoitrin and progoitrin, a pair of epimers that can be deglycosylated to epigoitrin and goitrin, respectively. These analytes were administered intravenously or intragastrically to male Sprague-Dawley rats, and the influence of 3(R/S)-configuration on the pharmacokinetics of both epimers in rat plasma was elucidated. The analytes and an internal standard (i.e., sinigrin) were resolved by LC-MS/MS on a reverse-phase ACQUITY UPLC™ HSS T3 column equilibrated and eluted with acetonitrile and water (0.1 % formic acid) at a flow rate of 0.3 mL/min. Quantitation was achieved by applying the multiple reaction monitoring mode, in the negative ion mode, at transitions of m/z 388 → 97 and m/z 358 → 97 for the epimers and sinigrin, respectively. The method demonstrated good linearity over the concentration range of 2-5000 ng/mL (r > 0.996). The lower limit of quantification for epiprogoitrin and progoitrin was 2 ng/mL. The interday and intraday accuracy and precision were within ±15 %. The extraction recovery, stability, and matrix effect were demonstrated to be within acceptable limits. The validated method was thus successfully applied for the pharmacokinetic study of both the epimers. After the rats received the same oral dose of the epimers, the pharmacokinetic profiles were similar. The maximum plasma concentration (C_max) and AUC values of epiprogoitrin were a bit higher than those of progoitrin, whereas the pharmacokinetic behaviours of the epimers were obviously different upon intravenous administration. The C_max and AUC values of epiprogoitrin were approximately three-fold higher than those of progoitrin, and the half-life of progoitrin was much shorter than that of epiprogoitrin. The oral bioavailability of progoitrin was 20.1 %-34.1 %, which is three times higher than that of epiprogoitrin.

Autophagic degradation of PML promotes susceptibility to HSV-1 by stress-induced corticosterone

Rationale: Herpes simplex virus type 1 (HSV-1) is a neurotropic virus that can cause a variety of clinical syndromes including mucocutaneous disease and HSV-1 encephalitis (HSE). Here, we characterize the molecular mechanisms underlying the susceptibility to HSV-1 under stressful conditions.

Methods: Restraint stress and corticosterone (CORT, a primary stress hormone) were respectively used to establish HSV-1 susceptible model in vivo and in vitro. Viral titers were determined by plaque assay. Western blotting, immunofluorescence, transmission electron microscopy (TEM), qRT-PCR, H&E staining, IHC staining and flow cytometry were employed to evaluate virus-related protein expressions and detect the activation of autophagy. Loss- and gain-function assays, co-immunoprecipitation (co-IP) technique and autophagy agonist/antagonist treatments were applied in mechanistic experiments.

Results: Restraint stress increased the susceptibility of mouse brain to HSV-1. Similarly, CORT treatment enhanced the susceptibility of neural cells to HSV-1. Furthermore, PML protein level in HSV-1 infected brain tissues and neural cells was remarkably decreased by stress treatment in vivo or CORT treatment in vitro, while its transcriptional level was not affected. Notably, a striking decline in protein expressions of ICP27 and gB was observed in PML-overexpressing cells, which was reversed by CORT treatment. By contrast, protein expression of gB was increased by knockdown with si-PML in virus-infected SH-SY5Y cells. We further discovered that CORT-driven PML degradation was dependent on the activation of autophagy in a ULK1-independent manner, rather than proteasome pathway. Bafilomycin A1 (BaF1) attenuated the augmentation effect of CORT on HSV-1 infection. The expressions of viral proteins were reduced in LC3-depleted cells, and the degradation of PML by CORT-induced autophagy was prevented in cells with LC3 knockdown by RNAi. Interestingly, PML was revealed to interact with the autophagic cargo receptor P62 and the autophagic effector protein LC3. Additionally, CORT failed to increase gB protein level when PML was silenced, providing direct evidence linking autophagic degradation of PML and CORT-induced virus susceptibility.

Conclusion: Our results revealed that restraint stress/CORT increased HSV-1 susceptibility by delivering PML into autolysosomes for degradation. The results obtained from in vitro and in vivo models not only demonstrated the adverse effects of stress on HSV-1 infection, but also systematically investigated the underlying molecular mechanisms. These discoveries broaden our understanding of the interplay between host and viruses, and a comprehensive understanding of the role of autophagy in viral infection will provide information for future development of innovative drugs against viral infection.

The antiviral and coronavirus-host protein pathways inhibiting properties of herbs and natural compounds - Additional weapons in the fight against the COVID-19 pandemic?

Introduction

As of March 11th, 2020, the World Health Organization declared the COVID-19 outbreak a pandemic. Articles published after the SARS-CoV-1 (2002) epidemic suggest that the use of an herbal-drug integrative medical approach could have contributed to a lower fatality rate and a more rapid response in controlling the outbreak.

Methods

Pubmed was searched for articles that investigated the antiviral properties and mechanisms of action of herbs or natural compounds against the SARS-coronavirus (CoV).

Results

Forty-three (43) relevant papers were located. A general count rendered 450+ herbs and natural compounds with antiviral properties against the SARS-CoV and related viruses. From the 43 articles, thirty-one (31) uncovered the mechanisms of action of the natural substances able to oppose the coronavirus.

Discussion

A series of herbs and natural compounds demonstrated moderate to strong antiviral activity. Research on many herbs-natural compounds also showed potent and significant inhibition of CoV-host protein pathways responsible for different phases of viral replication specifically targeting 3CL^PRO, PL^PRO, RdRp, helicase protein, S protein, N protein, 3a protein, Cathepsin L, Nsp1, Nsp3c, and ORF7a, and the S protein/ACE-2 interaction.

Conclusion

The herbs-natural compounds with antiviral activity and that caused inhibition/blockade of the CoV-host protein pathways are potential therapeutic candidates. The homology between the SARS-CoV-1 and SARS-CoV-2 is around 80%. Thus, effective herbs-compounds for the former would likely be beneficial for the latter also depending on target protein similarities between the viruses. Here we provide the mechanistic bases supporting an integrative approach that includes natural compounds to fight coronavirus infections.

Disturbed Yin-Yang balance: stress increases the susceptibility to primary and recurrent infections of herpes simplex virus type 1

Herpes simplex virus type 1 (HSV-1), a neurotropic herpes virus, is able to establish a lifelong latent infection in the human host. Following primary replication in mucosal epithelial cells, the virus can enter sensory neurons innervating peripheral tissues via nerve termini. The viral genome is then transported to the nucleus where it can be maintained without producing infectious progeny, and thus latency is established in the cell. Yin–Yang balance is an essential concept in traditional Chinese medicine (TCM) theory. Yin represents stable and inhibitory factors, and Yang represents the active and aggressive factors. When the organism is exposed to stress, especially psychological stress caused by emotional stimulation, the Yin–Yang balance is disturbed and the virus can re-engage in productive replication, resulting in recurrent diseases. Therefore, a better understanding of the stress-induced susceptibility to HSV-1 primary infection and reactivation is needed and will provide helpful insights into the effective control and treatment of HSV-1. Here we reviewed the recent advances in the studies of HSV-1 susceptibility, latency and reactivation. We included mechanisms involved in primary infection and the regulation of latency and described how stress-induced changes increase the susceptibility to primary and recurrent infections.

"Shanghuo" increases disease susceptibility: Modern significance of an old TCM theory

ETHNOPHARMACOLOGICAL RELEVANCE

"Shanghuo", a concept based on Traditional Chinese Medicine (TCM) theory, describes a status of Yin-Yang imbalance when Yang overwhelms Yin. The imbalance of Yin-Yang resembles the breaking of homeostasis and manifests by the impaired physiological functions, which leads to the onset, recurrence, and progression of diseases. Since ancient times, Chinese Materia Medica (CMM), such as herbal tea, has been applied as a treatment for "Shanghuo".

AIM OF THE STUDY

This review is aimed to describe the origin of "Shanghuo" from the Yin-Yang theory in TCM, as well as explore the relevance and correlations between "Shanghuo" and diseases susceptibility from the perspective of modern medicine. We also propose several strategies from CMM to improve the status of "Shanghuo" for the purpose of treating diseases.

METHODS

Systematic research of articles with keywords including Shanghuo, Yin-Yang, emotional stress and disease susceptibility was done by using the literature databases (Web of Science, Google Scholar, PubMed, CNKI). Related books, PhD and master's dissertations were also researched. Full scientific plant names were validated by "The Plant List" (www.theplantlist.org).

RESULTS

To date, a large number of publications have reported research on sub-health status, but studies about the theory or intervention of "Shanghuo" are rarely found. The articles we reviewed indicate that accumulated emotional stress is critical for the cause of "Shanghuo". As a status similar to sub-health, "Shanghuo" is also manifested by impaired physiological functions and decreased nonspecific resistance, which increase susceptibility to various diseases. What's more, some studies highlight the importance of TCM treatment towards "Shanghuo" in maintaining normal physiological functions, such as immunity, lipid metabolism and ROS clearance.

CONCLUSIONS

Researches on "Shanghuo" and its mechanism are every rare currently and are in need of investigation in the future. Studies on disease susceptibility recently are mostly about susceptible genes that relate to a few parts of people, however, for most of the people, accumulated emotional stress or other stressors is accountable for the susceptibility of diseases. Given that emotional stress plays an important factor in the causation of "Shanghuo", we reviewed the articles about this relevance and discussed the connection of "Shanghuo" with disease susceptibility in a novel perspective. In addition, we have reviewed the disease susceptibility model of restraint stress from its biochemical manifestation to application in CMM assessment. Although it would be a breakthrough in evaluating CMM efficacy of attenuating disease-susceptibility, understanding the comprehensive theory and establishing more models of "Shanghuo" would be required in further investigation.

Untargeted liquid chromatography coupled with mass spectrometry reveals metabolic changes in nitrogen-deficient Isatis indigotica Fortune

Isatis indigotica Fortune is a popular herb in traditional Chinese medicine, and various types of metabolites are the basis for its pharmacological efficacy. The biosynthesis and accumulation of these metabolites are closely linked to nitrogen availability; the benefits of low nitrogen application on the environment and herb quality are increasingly prominent. To analyze metabolic changes in the leaves and roots of I.indigotica in nitrogen deficiency conditions, and to identify the pathways and metabolites induced by low nitrogen availability, we used untargeted liquid chromatography coupled with mass spectrometry (UHPLC-TripleTOF) to obtain metabolomics profiling of I.indigotica under two N-deficiency treatments (0 kg/hm²; 337.5 kg/hm²) and normal nitrogen treatment (675 kg/hm²). A total of 447 metabolites were annotated. Principal component analysis separated the three nitrogen treatments. A greater diversity of metabolites was observed in roots than in leaves under N-deficiency treatments, suggesting that roots have a more important function in low N tolerance. Differential metabolites were mainly enriched in purine metabolism, phenylpropanoid biosynthesis, the shikimate pathway, tryptophan metabolism, and flavonoid biosynthesis that notably induced only in leaves in low nitrogen stress. Moderate N-deficiency benefits carbohydrate accumulation, whereas accumulation of most amino acids decreases. Uniquely, L-tryptophan was maintained at a high concentration in N-deficiency conditions. Low nitrogen stress induced the accumulation of some specialized metabolites (matairesinol, dictamnine, 5-hydroxyindoleacetate (serotonin) in roots and vitexin, xanthohumol, sinapyl alcohol in leaves). N-deficiency also increased the accumulation of adenosine and quality indicators of I.indigotica (indirubin-indigo, epigoitrin and anthranilic acid) in a certain degree. Our findings showed that nitrogen deficiency modified roots and leaves conditions of I.indigotica, affecting both the primary and secondary metabolism. Moderate nitrogen reduction was beneficial to the accumulation of active ingredients. Our methods and analysis are expected to provide an insight regarding the diversity of metabolites and regulation of their synthesis in low nitrogen application, and better investigate the nitrogen deficiency effect on I.indigotica.

Indirubin derivatives are potent and selective anti-Trypanosoma cruzi agents

Current treatment for combatting Chagas disease, a life-threatening illness caused by the kinetoplastid protozoan parasite Trypanosoma cruzi is inadequate, and thus the discovery of new antiparasitic compounds is of prime importance. Previous studies identified the indirubins, a class of ATP kinase inhibitors, as potent growth inhibitors of the related kinetoplastid Leishmania. Herein, we evaluated the inhibitory activity of a series of 69 indirubin analogues screened against T. cruzi trypomastigotes and intracellular amastigotes. Seven indirubins were identified as potent T. cruzi inhibitors (low μΜ, nM range). Cell death analysis of specific compounds [3'oxime-6-bromoindirubin(6-BIO) analogues 10, 11 and 17, bearing a bulky extension on the oxime moiety and one 7 substituted analogue 32], as evaluated by electron microscopy and flow cytometry, showed a different mode of action between compound 32 compared to the three 6-BIO oxime- substituted indirubins, suggesting that indirubins may kill the parasite by different mechanisms dependent on their substitution. Moreover, the efficacy of four compounds that show the most potent anti-parasitic effect in both trypomastigotes and intracellular amastigotes (10, 11, 17, 32), was evaluated in a mouse model of T. cruzi infection. Compound 11 (3ʹpiperazine-6-BIO) displayed the best in vivo efficacy (1/6 mortality, 94.5% blood parasitaemia reduction, 12 dpi) at a dose five times reduced over the reference drug benznidazole (20 mg/kg vs100 mg/kg). We propose 3ʹpiperazine-6-BIO as a potential lead for the development of new treatments of Chagas disease.

Traditional Chinese Medicine as a Potential Source for HSV-1 Therapy by Acting on Virus or the Susceptibility of Host

Herpes simplex virus type 1 (HSV-1) is the most common virus, with an estimated infection rate of 60–95% among the adult population. Once infected, HSV-1 can remain latent in the host for a lifetime and be reactivated in patients with a compromised immune system. Reactivation of latent HSV-1 can also be achieved by other stimuli. Though acyclovir (ACV) is a classic drug for HSV-1 infection, ACV-resistant strains have been found in immune-compromised patients and drug toxicity has also been commonly reported. Therefore, there is an urge to search for new anti-HSV-1 agents. Natural products with potential anti-HSV-1 activity have the advantages of minimal side effects, reduced toxicity, and they exert their effect by various mechanisms. This paper will not only provide a reference for the safe dose of these agents if they are to be used in humans, referring to the interrelated data obtained from in vitro experiments, but also introduce the main pharmacodynamic mechanisms of traditional Chinese medicine (TCM) against HSV-1. Taken together, TCM functions as a potential source for HSV-1 therapy by direct (blocking viral attachment/absorption/penetration/replication) or indirect (reducing the susceptibility to HSV-1 or regulating autophagy) antiviral activities. The potential of these active components in the development of anti-HSV-1 drugs will also be described.

Indirubin suppresses ovarian cancer cell viabilities through the STAT3 signaling pathway

Background

Indirubin is the active component of Danggui Longhui Wan, a traditional Chinese medicine formulation. Due to its anti-inflammation and anti-tumor effects, indirubin has been widely used for the treatment of inflammation, cancer, and other chronic disease. Herein, we aimed to investigate the role and mechanism of indirubin in human ovarian cancer cell proliferation.

Materials and methods

The cell viability was determined by Cell Counting Kit-8 and colony formation assays by treatment with different dosages of indirubin over 72 hours. Apoptosis was examined by flow cytometry with fluorescein isothiocyanate Annexin V Apoptosis Detection Kit. Western blot assay was finally applied to analyze the expression of cancer-related STAT3 pathway and its downstream proteins.

Results

Indirubin was found to significantly inhibit cell viability and induce apoptosis in 2 human ovarian cancer cell lines. Mechanistic studies revealed that indirubin treatment led to reduced levels of phosphorylated-STAT3, thus repressing the downstream pro-survival proteins and elevating pro-apoptosis ones.

Conclusion

Our study provided the evidence for anti-survival activity of indirubin by inhibiting cell viability and inducing apoptosis in human ovarian cancer cells, which involved impaired STAT3 signaling pathway. Our findings further support indirubin as a potential drug candidate against human ovarian cancer.