Traditional Chinese herbs as chemical resource library for drug discovery of anti-infective and anti-inflammatory

Tetramethylpyrazine alleviates hypoxia-induced proliferation, migration, and inflammatory response of fibroblast-like synoviocytes via inhibiting the HIF-1α- circCDC42BPB pathway

OBJECTIVES

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease, which might trigger cartilage, bone damage, and disability. Recent studies have suggested that Tetramethylpyrazine (TMP), an alkaloid monomer isolated from the rhizome of the traditional herbal medicine Ligusticum wallichii Franch, exerts a broad spectrum of pharmacological properties, containing anti-inflammatory. This study aimed to analyze the role and underlying mechanism of TMP in RA.

METHODS

Under Hypoxia condition, RA-Fibroblast-like synoviocyte (FLS) were treated with TMP at different doses. Cell viability, proliferation, cell cycle progression, and migration were detected using Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, flow cytometry assay, wound healing assay, and transwell assay. Cyclin D1, Proliferating cell nuclear antigen (PCNA), Matrix metalloproteinase-2 (MMP2), MMP9, and hypoxia-inducible factor-1α (HIF-1α) protein levels were measured using western blot assay. Interleukin-6 (IL-6) and IL-8 were evaluated using ELISA. Circular RNA (circRNA) hsa_circ_0005178 (circCDC42BPB), CDC42BPB, and HIF-1α expression were determined using real-time quantitative polymerase chain reaction (RT-qPCR). Binding between HIF-1α and CDC42BPB promoter was predicted by JASPAR and verified using dual-luciferase reporter and Chromatin immunoprecipitation (ChIP) assays.

RESULTS

TMP might hinder FLS proliferation, cycle progression, migration, and inflammatory response under hypoxic conditions. CircCDC42BPB expression was increased in RA patients and RA-FLSs treated with hypoxia, while its level was obviously reduced in RA-FLSs treated with hypoxia and TMP. TMP might abolish hypoxia-induced circCDC42BPB expression. Upregulation of circCDC42BPB might partially overturn the repression of TMP on hypoxia-caused RA-FLS damage. TMP might regulate circCDC42BPB level via HIF-1α in RA-FLSs under hypoxic conditions.

CONCLUSION

TMP might block RA-FLS injury partly via regulating the HIF-1α- circCDC42BPB pathway, providing a promising therapeutic target for RA.

High-resolution neuraminidase inhibition profiling of Arnebia euchroma (Royle) I.M. Johnst. based on HR-MS and target isolation: An example study of anti-infectious constituents in traditional Chinese medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese Medicines (TCMs) are an important source to discover new anti-infectious drugs. Neuraminidases (NAs) not only play a key role on human health, but also are promising targets for anti-infectious drugs. Arnebia euchroma which is a widely used traditional Chinese medicine with the effect of cooling blood and detoxifying showed potential inhibitory activities on both bacterial NA and virus NA, suggesting that the material basis of A. euchroma deserves in-depth study.

AIM OF THE STUDY

To investigate the anti-infectious constituents of A. euchroma based on NA inhibition.

MATERIAL AND METHODS

A HPLC-DAD system incorporated an auto-sampler was used for micro-fractionation. A nanoliter liquid handler and a high sensitive multimode plate reader system were used for high throughput NA inhibition screening. Thus a high-resolution NA inhibition profiling platform was constructed. The structures of potential active components in A. euchroma obtained by the high-resolution bioassay profiling were identified by DAD and MS in parallel. Then, a target and rapid isolation of NAIs from A. euchroma was achieved under the guidance of the spectrum-effect relationship obtained above. Finally, the isolated compounds were elucidated by extensive spectroscopic methods and their bioactivities were validated by in vitro assay and molecular docking.

RESULTS

16 potential active ingredients in A. euchroma were isolated and identified, including a new mero-monoterpenoid. The in vitro bioassay results revealed that 12 out of the 16 isolated compounds showed potent inhibitory activities on bacterial NA (IC50s = 1-6 μM) and five of them exhibited potent anti-microbial activities on methicillin-resistant Staphylococccus aureus (MRSA) with MICs in the range of 0.5-4 μg/mL. Furthermore, some isolated compounds showed equal or even better inhibitory activities on oseltamivir resistant viral NA than oseltamivir sensitive NA. The mechanism study in silicon revealed that these natural compounds possessed absolutely different binding modes on the bacterial and viral NAs.

CONCLUSIONS

Our study gave a clear spectrum-effect relationship of A. euchroma, providing a scientific evidence for future study of the multi-components synergistic effect of TCMs.

An Updated Review on Developing Small Molecule Kinase Inhibitors Using Computer-Aided Drug Design Approaches

Small molecule kinase inhibitors (SMKIs) are of heightened interest in the field of drug research and development. There are 79 (as of July 2023) small molecule kinase inhibitors that have been approved by the FDA and hundreds of kinase inhibitor candidates in clinical trials that have shed light on the treatment of some major diseases. As an important strategy in drug design, computer-aided drug design (CADD) plays an indispensable role in the discovery of SMKIs. CADD methods such as docking, molecular dynamic, quantum mechanics/molecular mechanics, pharmacophore, virtual screening, and quantitative structure-activity relationship have been applied to the design and optimization of small molecule kinase inhibitors. In this review, we provide an overview of recent advances in CADD and SMKIs and the application of CADD in the discovery of SMKIs.

Triterpenoid and Coumarin Isolated from Astilbe grandis with Anti-Inflammatory Effects through Inhibiting the NF-κB Pathway in LPS-Induced RAW264.7 Cells

The roots of Astilbe grandis, known as "Ma sang gou bang", are used as a Miao traditional medicine with anti-inflammatory and analgesic properties. However, the active components and mechanism of action of this plant remain mostly uncharacterized. The aim of this study was to identify its active components and verify their pharmacological activity. The extract of A. grandis root was separated using various chromatographic methods. As a result, we obtained one novel triterpenoid, named astigranlactone (1), which has an unusual lactone moiety formed between C-7 and C-27. Additionally, a known coumarin compound, 11-O-galloyl bergenin (2) was isolated from this plant. The structures of these two compounds were elucidated by extensive NMR experiments in conjunction with HR-ESI-MS data. To the best of our knowledge, both compounds were isolated from this species for the first time. Moreover, we tested the anti-inflammation effect of the two compounds by establishing a cellular inflammation model induced by LPS in RAW264.7 cells. The effect of different concentrations of these compounds on the activity of RAW264.7 cells was assessed using a CCK8 assay. The levels of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) in the supernatant of each group were evaluated using the Griess method and an enzyme-linked immunosorbent assay (ELISA). Western blot and quantitative real-time PCR (qRT-RCR) were used to measure the levels of cyclooxygenase 2 (COX-2) and nitric oxide synthase (iNOS) gene expression. Our findings revealed that these two compounds inhibited the high levels of NO, TNF-α, IL-6, IL-1β, COX-2, and iNOS (induced by LPS). Mechanistic studies demonstrated that these two compounds reduced the activation of the nuclear transcription factor-B (NF-κB) signaling pathway by inhibiting the phosphorylation of p65. Therefore, our study indicates that compounds 1 and 2 can exert a definite anti-inflammatory effect by inhibiting the NF-κB signaling pathway.

β-Carboline alkaloids from Picrasma quassioides and their 3D-QSAR study on anti-inflammation in LPS-induced RAW 264.7 cells

Two new β-carboline alkaloids (1-2), 1-pyrrolidone propionyl-β-carboline (1) and 1-(3-hydroxy-2-oxopiperidine-1-ethyl)-4,8-dimethoxyl-β-carboline (2), named kumujantine W and J respectively, together with ten known compounds (3-12) were isolated from the stems of Picrasma quassioides (D. Don) Benn. Their structures were elucidated from spectral data including 1D and 2D NMR, UV, IR, HR-ESI-MS spectroscopic analysis and ECD calculations as well as by comparison to the reference databases or literature. The anti-inflammatory effects of these alkaloids (1-12) and six other β-carboline alkaloids (13-18) in LPS-induced RAW 264.7 cells were evaluated by measuring nitric oxide (NO) concentrations. Among them, compounds 1, 3, 6, 15, and 17 could inhibit the secretion of NO, displaying significant anti-inflammatory activity without affecting cell viability in vitro, and 3D-QSAR analysis further revealed the influence of groups on the activity in β-carboline alkaloids.

Discovery of pulmonary fibrosis inhibitor targeting TGF-β RI in Polygonum cuspidatum by high resolution mass spectrometry with in silico strategy

Pulmonary fibrosis (PF) is an irreversible lung disease that is characterized by excessive scar tissue with a poor median survival rate of 2-3 years. The inhibition of transforming growth factor-β receptor type-I (TGF-β RI) by an appropriate drug may provide a promising strategy for the treatment of this disease. Polygonum cuspidatum (PC) is a well-known traditional Chinese herbal medicine which has an anti-PF effect. Accordingly, a combination of high resolution mass spectrometry with an in silico strategy was developed as a new method to search for potential chemical ingredients of PC that target the TGF-β RI. Based on this strategy, a total of 24 ingredients were identified. Then, absorption, distribution, metabolism, and excretion (ADME)-related properties were subsequently predicted to exclude compounds with potentially undesirable pharmacokinetics behaviour. Molecular docking studies on TGF-β RI were adopted to discover new PF inhibitors. Eventually, a compound that exists in PC known as resveratrol was proven to have excellent biological activity on TGF-β RI, with an IC₅₀ of 2.211 μM in vitro. Furthermore, the complex formed through molecular docking was tested via molecular dynamics simulations, which revealed that resveratrol had strong interactions with residues of TGF-β RI. This study revealed that resveratrol has significant potential as a treatment for PF due to its ability to target TGF-β RI. In addition, this research demonstrated the exploration of natural products with excellent biological activities toward specific targets via high resolution mass spectrometry in combination with in silico technology is a promising strategy for the discovery of novel drugs.

Exploring therapeutic mechanisms of San-Huang-Tang in nonalcoholic fatty liver disease through network pharmacology and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

San-Huang-Tang (SHT), a traditional Chinese medicine (TCM) formula, has been clinically used to treat obesity and type 2 diabetes mellitus. Recently it has proved that SHT have a good effect on non-alcoholic fatty liver disease (NAFLD).

AIM OF THE STUDY

Our study was designed to investigate the therapeutic mechanisms of the SHT against NAFLD. The data of SHT were obtained through network pharmacology platform and validated experimentally in vivo and in vitro.

MATERIALS AND METHODS

The candidate targets of SHT were predicted by network pharmacological analysis and crucial targets were chosen by the protein-protein interaction (PPI) network. Furthermore, Gene Ontology (GO) and Kyoto encyclopedia of genes and Genomes (KEGG) were applied to analyze the NAFLD-related signaling pathways affected by SHT, and then the analysis results were verified with molecular biological experiments in vivo and in vitro.

RESULTS

Molecules were screened with network pharmacological analysis, and then the improvement of insulin resistance of NAFLD mice was measured by IPITTs and IPGTTs. Through series of molecular experiments, it is revealed that SHT could increase the transcription of insulin receptor (INSR) and insulin receptor substrate (IRS1), and enhance the phosphorylation of both threonine protein kinase (AKT) and forkhead box O1 (FoxO1).

CONCLUSIONS

Screened by bioinformatics and verified by experiments in vivo and in vitro, SHT could contribute to NAFLD by affecting insulin resistance via activating INSR/IRS1/AKT/FoxO1 pathway. Our research findings provide not only an experimental basis for the therapeutic effect of SHT but also a new target against NAFLD.

Scutellarin enhances anti-tumor immune responses by reducing TNFR2-expressing CD4+Foxp3+ regulatory T cells

One characteristic of tumor-associated CD4⁺Foxp3⁺ regulatory T cells (Tregs) is the high expression of tumor necrosis factor receptor type II (TNFR2), a receptor that mediates the decisive effect of tumor necrosis factor (TNF) in the activation and expansion of Tregs. There is increasing evidence that inhibition of TNFR2 can enhance anti-tumor immune responses. Therefore, we screened Chinese herbal extracts for their capacity to block TNF-TNFR2 interaction. The results showed that the treatment with a Chinese herb extract could inhibit TNFR2-induced biological responses in vitro, including the proliferation of TNFR2⁺ Tregs. Our subsequent study led to the identification of flavonoid compound scutellarin was responsible for the activity. Our results showed that scutellarin is able to disrupt the interaction of TNF-TNFR2 and inhibited the phosphorylation of p38 MAPK, a down-stream signaling component of TNFR2. Importantly, in vivo scutellarin treatment markedly enhanced the efficacy of tumor immunotherapy with CpG oligodeoxynucleotide in mouse CT26 colon cancer model. This effect of scutellarin was associated with the reduction of the number of tumor-infiltrating TNFR2-expressing Tregs and increased tumor infiltration of interferon-γ-producing CD8⁺ T cells. Our result also suggests that scutellarin or its analogs may be used as an adjuvant to enhance the anti-tumor effect of immunotherapeutic agent by eliminating TNFR2⁺ Treg activity.

Anticancer effects of herbal medicines in pancreatic ductal adenocarcinoma through modulation of steroid hormone response proteins

Many individual herbs and herbal formulae have been demonstrated to provide safe and effective treatment for pancreatic ductal adenocarcinoma (PDAC); however, the therapeutic mechanisms underlying their effects have not been fully elucidated. A total of 114 herbal formulae comprising 216 single herbal medicines used to treat PDAC were identified. Cluster analysis revealed a core prescription including four herbs [Glycyrrhizae Radix et Rhizome (Gan Cao), Codonopsis Radix (Dang Shen), Citri Reticulatae Pericarpium (Chen Pi), and Pinelliae Rhizoma (Ban Xia)] in combination to treat PDAC, and 295, 256, 141, and 365 potential targets were screened for each of these four herbs, respectively. PDAC-related proteins (n = 2940) were identified from the DisGeNET database. Finally, 44 overlapping targets of herbs and PDAC were obtained, representing potential targets of the herbal medicines for PDAC treatment. GO enrichment analysis indicated that targets common to herbs and PDAC primarily functioned in response to steroid hormones. KEGG pathway enrichment analysis indicated that the herbs may prevent PDAC by influencing apoptotic, p53, and PI3K/Akt signaling pathways. Further, molecular docking analysis indicated that of identified bioactive compounds, stigmasterol, phaseol, perlolyrine, shinpterocarpin, and licopyranocoumarin have good binding ability with proteins involved in responses to steroid hormones, while stigmasterol, phaseol, perlolyrine, and DIOP have good binding ability with PTGS2(also known as COX-2), ESR1, ESR2, AR, and PGR. The anti-PDAC activity of herbal medicines may be mediated via regulation of proteins with roles in responses to steroid hormones. This study provides further evidence supporting the potential for use of herbal medicines to treat PDAC.

A chemoinformatic analysis of atoms, scaffolds and functional groups in natural products

In the quest to know why natural products (NPs) have often been considered as privileged scaffolds for drug discovery purposes, many investigations into the differences between NPs and synthetic compounds have been carried out. Several attempts to answer this question have led to the investigation of the atomic composition, scaffolds and functional groups (FGs) of NPs, in comparison with synthetic drugs analysis. This chapter briefly describes an atomic enumeration method for chemical libraries that has been applied for the analysis of NP libraries, followed by a description of the main differences between NPs of marine and terrestrial origin in terms of their general physicochemical properties, most common scaffolds and “drug-likeness” properties. The last parts of the work describe an analysis of scaffolds and FGs common in NP libraries, focusing on huge NP databases, e.g. those in the Dictionary of Natural Products (DNP), NPs from cyanobacteria and the largest chemical class of NP – terpenoids.

Omics strategies decipher therapeutic discoveries of traditional Chinese medicine against different diseases at multiple layers molecular-level

Traditional Chinese medicine (TCM) has been broadly used for the personalized treatment of many diseases in China for thousands of years. In the past century, TCM was also introduced to other Asian countries and even the Western world. Increasing evidence has shown that TCM has the capacity to treat numerous complex diseases in the clinic, such as cardiovascular diseases (CVDs), infectious diseases, metabolic diseases, and neurodegenerative diseases. However, the earlier lack of analytical strategies to annotate the chemical complexity has severely impeded the modern study and translational application of TCM. This critical review aims to explore and exploit applications of systems biology-driven omics methods in TCM against a diversity of diseases, toward the specific use of TCM to treat patients with different diseases. Such effort shall enhance the applicability of systems biology-driven omics strategies in deciphering the mechanisms by which TCM treats different diseases and may lead to the discovery of new therapeutic directions. In addition, we proposed the possible strategies to innovate the applicable pattern of omics technologies in TCM niches, such as precision-modification metabolomics and chinmedomics methods, allowing to unveil the complexity of TCM, which must enable TCM to serve better for the population-health. Taken together, this review eventually shall highlight the core value of omics technologies in innovating TCM to combat the diseases in a new horizon.

Re-Du-Ning inhalation solution exerts suppressive effect on the secretion of inflammatory mediators via inhibiting IKKα/β/IκBα/NF-κB, MAPKs/AP-1, and TBK1/IRF3 signaling pathways in lipopolysaccharide stimulated RAW 264.7 macrophages

Background: Re-Du-Ning inhalation solution (RIS) is a novel preparation derived from the Re-Du-Ning injection, which has been clinically used to treat respiratory diseases such as pneumonia for more than twenty years in China. However, scant reports have been issued on its anti-inflammatory mechanisms. Aim: we investigated the suppressive effect of RIS on inflammatory mediators and explored the underlying mechanism of action. Methods: RIS freeze dried powder was characterized by HPLC analysis. Lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage was selected as the cell model. The cell viability was determined by using the MTT assay. Moreover, the production of nitric oxide (NO) was measured by the Griess reaction. The protein secretions from inflammatory mediators were determined by the enzyme-linked immunosorbent assay (ELISA). The protein levels and enzyme activities were examined by Western blotting. The nuclear translocation of nuclear factor-kappa B (NF-κB), AP-1, and IRF3 was further explored by immunofluorescence assay. Results: the viability of the RAW 264.7 cells was not significantly changed after 24 h incubation with RIS concentration up to 400 μg mL⁻¹. The RIS remarkably reduced the production of NO and prostaglandin E₂ (PGE₂), and downregulated the expression of iNOS and COX-2. The concentrations of cytokines (IL-1β, IL-6, and TNF-α) and chemokines (MCP-1, CCL-5, and MIP-1α) in the culture medium were significantly decreased by the RIS treatment. Furthermore, the phosphorylation of IκB-α, IKKα/β, TBK1, ERK, p38, JNK, NF-κB, AP-1, and IRF3 was downregulated by the RIS treatment. The nuclear translocation of NF-κB, AP-1, and IRF3 was also inhibited after the RIS treatment. Conclusion: the suppressive effect of RIS is associated with the regulated NF-κB, AP-1, and IRF3 and their upstream proteins. This study provides a pharmacological basis for the application of RIS in the treatment of inflammatory disorders.

Re-Du-Ning inhalation solution suppresses the production of inflammatory mediators through TLR4 signaling pathway.

Evaluation of the protective effects of 13 traditional Chinese medicine compounds on ionizing radiation injury: bupleurum, shenmai, and breviscapine as candidate radioprotectors

Drugs are being sought that are effective as radioprotection for use in both planned and unplanned radiation exposure.

Vam3, a Compound Derived from Vitis amurensis Rupr., Attenuated Colitis-Related Tumorigenesis by Inhibiting NF-κB Signaling Pathway

Background: Chronic inflammation is one of the important mediators of colitis-related colon cancer (CRC). Abundant mast cells (MCs) were observed in the tumor microenvironment and mediators released upon MC activation play an important role in the process of chronic inflammation. Previously, we found that activation of intestine mucosal MCs recruited and modulated the inflammatory CD11b⁺Gr1⁺ cells to promote the CRC development. In the current study we investigated the effects of Vam3, a resveratrol dimer with potent anti-inflammatory effects, on CRC development.

Methods: RBL-2H3 cells, a basophilic leukemia cell line, were pretreated with 2.5 or 5 µM Vam3 and then stimulated with dinitrophenol-conjugated bovine serum albumin (DNP-BSA) plus lipopolysaccharide (LPS). The MC degranulation was determined by measuring β-hexosaminidase release. Generation of TNF-α and IL-6 in RBL-2H3 cells or in peritoneal macrophages was determined by ELISA and real-time qPCR. NF-κB p65 and phospho-NF-κB p65 expression was determined by Western blotting. NF-κB activity in RAW264.7 cells was determined by luciferase reporter assay. CRC was induced in C57BL/6 mice by intraperitoneal injection of azoxymethane (AOM), followed by oral exposure to dextran sodium sulfate (DSS). Vam3 at 50 mg/kg, or disodium cromoglycate (DSCG, MC stabilizer) at 100 mg/kg, or vehicle were administrated to the mice 4 weeks after DSS withdrawal. Levels of TNF-α, IL-6, and mouse MC protease-1 were determined by ELISA. Infiltration of CD11b⁺Gr1⁺ cells was determined by flow cytometry analysis. One-way ANOVA was used to compare difference between groups.

Results: Pretreatment with Vam3 significantly inhibited RBL-2H3 cell degranulation and inflammatory cytokine production from RBL-2H3 cells and from peritoneal macrophages. After Vam3 treatment, NF-κB activity in RAW264.7 cells, and expressions of phospho-NF-κB p65 in RBL-2H3 cells and in peritoneal macrophages were significantly down-regulated. In the AOM plus DSS-induced CRC murine model, the Vam3 and DSCG-treated mice had less tumor numbers than those treated with vehicle. Expression of phospho-NF-κB p65, production of inflammatory cytokines, and infiltration of MCs and CD11b⁺Gr1⁺ cells were attenuated in the Vam3-treated mice.

Conclusion: Vam3 treatment could attenuate the CRC development. This effect may be due to its inhibition on NF-κB signaling pathway in MCs and macrophages of the inflamed intestines.

Medicinal Bioprospecting of the Amazon Rainforest: A Modern Eldorado?

Ignorant of the New World, Europeans believed in El Dorado, a hidden city of immense wealth in gold. Many consider the Amazonian forest to be a medicinal treasure chest and potentially the largest drug dispensary in the world. Yet, the quest to obtain drugs from indigenous tropical plants remains elusive. Here, we assess the potential of new technologies to tap into the metabolic diversity of tropical plants. We also consider how regulations affect access to plant resources. We conclude that, although the road to this medicinal El Dorado may be long and arduous, many other smaller but still valuable finds are hidden along the way.

Drug discovery of neurodegenerative disease through network pharmacology approach in herbs

Neurodegenerative diseases, referring to as the progressive loss of structure and function of neurons, constitute one of the major challenges of modern medicine. Traditional Chinese herbs have been used as a major preventive and therapeutic strategy against disease for thousands years. The numerous species of medicinal herbs and Traditional Chinese Medicine (TCM) compound formulas in nervous system disease therapy make it a large chemical resource library for drug discovery. In this work, we collected 7362 kinds of herbs and 58,147 Traditional Chinese medicinal compounds (Tcmcs). The predicted active compounds in herbs have good oral bioavailability and central nervous system (CNS) permeability. The molecular docking and network analysis were employed to analyze the effects of herbs on neurodegenerative diseases. In order to evaluate the predicted efficacy of herbs, automated text mining was utilized to exhaustively search in PubMed by some related keywords. After that, receiver operator characteristic (ROC) curves was used to estimate the accuracy of predictions. Our study suggested that most herbs were distributed in family of Asteraceae, Fabaceae, Lamiaceae and Apocynaceae. The predictive model yielded good sensitivity and specificity with the AUC values above 0.800. At last, 504 kinds of herbs were obtained by using the optimal cutoff values in ROC curves. These 504 herbs would be the most potential herb resources for neurodegenerative diseases treatment. This study would give us an opportunity to use these herbs as a chemical resource library for drug discovery of anti-neurodegenerative disease.

Sonodynamic action of hypocrellin B on methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) commonly causes refractory infections and has recently become a serious public health concern. The present study was designed to investigate sonodynamic action of hypocrellin B on MRSA. A MRSA strain (ATCC BAA-43) was used in the present study. The dark toxicity of hypocrellin B on MRSA and its uptake in MRSA first were measured. And then bacteria were incubated with hypocrellin B and exposed to ultrasound. After sonodynamic treatment, colony forming unit assay and bacterial viability assay were conducted. Membrane permeability assay, DNA fragmentation assay, and DNA synthesis assay were also performed to examine the underlying mechanism. The results showed that hypocrellin B at concentrations of up to 500 μM had no toxicity to MRSA in the dark. After incubation for 50 min, hypocrellin B could be maximally absorbed by MRSA, and exhibited significant sonodynamic activity in a dose-dependent manner. The 5-log reduction in colony forming unit (CFU) was observed after hypocrellin B (40 μM) treatment at an intensity of 1.38 W/cm(2) ultrasound for 5 min. Compared to the control, hypocrellin B alone and ultrasound sonication alone group, more dead cells were found and bacterial membrane integrity was notably damaged after sonodynamic treatment of hypocrellin B. However, no remarkable DNA damage was found in MRSA after sonodynamic treatment of hypocrellin B. All the findings demonstrated that hypocrellin B could serve as a potential antibacterial sonosensitizer to significantly cause damage to the membrane integrity of MRSA and inhibit its growth under ultrasound sonication.

In silico prediction of prostaglandin D2 synthase inhibitors from herbal constituents for the treatment of hair loss

ETHNOPHARMACOLOGICAL RELEVANCE

Many herbal topical formulations have been marketed worldwide to prevent hair loss or promote hair growth. Certain in vivo studies have shown promising results among them; however, the effectiveness of their bioactive constituents remains unknown.

AIM OF THE STUDY

Recently, prostaglandin D2 (PGD2) inhibition has been discovered as a pharmacological mechanism for treating androgenic alopecia (AGA). This present study was aimed to identify prostaglandin D2 synthase (PTGDS) inhibitors in traditional Chinese medicines (TCMs) for treating AGA.

MATERIALS AND METHODS

In this study, 389 constituents of 12 selected herbs were docked into 6 different crystal structures of PTGDS. The accuracy of the docking methods was successfully validated with experimental data from the ZINC In Man (Zim) database using receiver operating characteristic (ROC) studies. Seven essential drug properties were predicted for topical formulation: skin permeability, sensitisation, irritation, corrosion, mutagenicity, tumorigenicity and reproductive effects.

RESULTS

Many constituents of the twelve herbs were found to have more advanced binding energies than the experimentally proved PTGDS inhibitors, but many of them were indicative of at least one type of skin adverse reactions, and exhibited poor skin permeability.

CONCLUSIONS

Overall, ricinoleic acid, acteoside, amentoflavone, quercetin-3-O-rutinoside and hinokiflavone were predicted to be PTGDS inhibitors with good pharmacokinetic properties and minimal adverse skin reactions. These compounds have the highest potential for further in vitro and in vivo investigation with the aim of developing safe and high-efficacy hair loss treatment.

Synthesis of a Functionalized Benzofuran as a Synthon for Salvianolic Acid C Analogues as Potential LDL Antioxidants

A palladium mediated synthesis of a common synthon for the syntheses of antioxidant analogues of naturally occurring salvianolic acids is presented. The synthetic route may be used to obtain analogues with a balanced lipophilicity/hydrophilicity which may result in potentially interesting LDL antioxidants for the prevention of cardiovascular diseases.

Effects of Mentha suaveolens essential oil on Chlamydia trachomatis

Chlamydia trachomatis, the most common cause of sexually transmitted bacterial infection worldwide, has a unique biphasic developmental cycle alternating between the infectious elementary body and the replicative reticulate body. C. trachomatis is responsible for severe reproductive complications including pelvic inflammatory disease, ectopic pregnancy, and obstructive infertility. The aim of our study was to evaluate whether Mentha suaveolens essential oil (EOMS) can be considered as a promising candidate for preventing C. trachomatis infection. Specifically, we investigated the in vitro effects of EOMS towards C. trachomatis analysing the different phases of chlamydial developmental cycle. Our results demonstrated that EOMS was effective towards C. trachomatis, whereby it not only inactivated infectious elementary bodies but also inhibited chlamydial replication. Our study also revealed the effectiveness of EOMS, in combination with erythromycin, towards C. trachomatis with a substantial reduction in the minimum effect dose of antibiotic. In conclusion, EOMS treatment may represent a preventative strategy since it may reduce C. trachomatis transmission in the population and, thereby, reduce the number of new chlamydial infections and risk of developing of severe sequelae.

Anti-inflammatory effects of Dendrobium nobile derived phenanthrenes in LPS-stimulated murine macrophages

Dendrobium nobile belongs to the Orchidaceae family and is one of the medicinal herbs used in traditional Chinese medicine as a therapeutic agent for gastrointestinal and cardiovascular diseases. In this study, we separated three phenanthrenes (ephemeranthol A (EA), 1,5,7-trimethoxyphenanthren-2-ol (TP), dehydroorchinol (DO)) from D. nobile, and compared their anti-inflammatory activities. TP is a new phenanthrene compound and its structure was determined from (1)H, (13)C NMR and HR-ESI-MS data. To analyze the anti-inflammatory activities of the phenanthrenes, Raw 264.7 cells were used, since they are immature-macrophages and easily matured by LPS stimulation. EA and DO showed anti-inflammatory activities in the activated Raw 264.7 cells. That is, we showed that EA is a potent inhibitor of the production of nitric oxide and pro-inflammatory cytokines. The inhibitory activities of phenanthrenes were found to be caused by blockage of NF-κB activation and the phosphorylation of MAP kinases in the macrophages. These results are expected to serve as a guide for future studies on the ability of phenanthrenes to inhibit acute and chronic inflammatory diseases.