Computational and experimental prediction of molecules involved in the anti-melanoma action of berberine

Characterization of GABAergic marker expression in prefrontal cortex in dexamethasone induced depression/anxiety model

Background

The pivotal responsibility of GABAergic interneurons is inhibitory neurotransmission; in this way, their significance lies in regulating the maintenance of excitation/inhibition (E/I) balance in cortical circuits. An abundance of glucocorticoids (GCs) exposure results in a disorder of GABAergic interneurons in the prefrontal cortex (PFC); the relationship between this status and an enhanced vulnerability to neuropsychiatric ailments, like depression and anxiety, has been identified, but this connection is still poorly understood because systematic and comprehensive research is lacking. Here, we aim to investigate the impact of dexamethasone (DEX, a GC receptor agonist) on GABAergic interneurons in the PFC of eight-week-old adult male mice.

Methods

A double-blind study was conducted where thirty-two mice were treated subcutaneously either saline or DEX (0.2 mg/10 ml per kg of body weight) dissolved in saline daily for 21 days. Weight measurements were taken at five-day intervals to assess the emotional changes in mice as well as the response to DEX treatment. Following the 21-day regimen of DEX injections, mice underwent examinations for depression/anxiety-like behaviours and GABAergic marker expression in PFC.

Results

In a depression/anxiety model generated by chronic DEX treatment, we found that our DEX procedure did trigger depression/anxiety-like behaviors in mice. Furthermore, DEX treatment reduced the expression levels of a GABA-synthesizing enzyme (GAD67), Reelin, calcium-binding proteins (parvalbumin and calretinin) and neuropeptides co-expressed in GABAergic neurons (somatostatin, neuropeptide Y and vasoactive intestinal peptide) in the PFC were reduced after 21 days of DEX treatment; these reductions were accompanied by decreases in brain size and cerebral cortex thickness.

Conclusion

Our results indicate that a reduction in the number of GABAergic interneurons may result in deficiencies in cortical inhibitory neurotransmission, potentially causing an E/I imbalance in the PFC; this insight suggests a potential breakthrough strategy for the treatment of depression and anxiety.

Berberine prevents NAFLD and HCC by modulating metabolic disorders

Non-alcoholic fatty liver disease (NAFLD) is a global metabolic disease with high prevalence in both adults and children. Importantly, NAFLD is becoming the main cause of hepatocellular carcinoma (HCC). Berberine (BBR), a naturally occurring plant component, has been demonstrated to have advantageous effects on a number of metabolic pathways as well as the ability to kill liver tumor cells by causing cell death and other routes. This permits us to speculate and make assumptions about the value of BBR in the prevention and defense against NAFLD and HCC by a global modulation of metabolic disorders. Herein, we briefly describe the etiology of NAFLD and NAFLD-related HCC, with a particular emphasis on analyzing the potential mechanisms of BBR in the treatment of NAFLD from aspects including increasing insulin sensitivity, controlling the intestinal milieu, and controlling lipid metabolism. We also elucidate the mechanism of BBR in the treatment of HCC. More significantly, we provided a list of clinical studies for BBR in NAFLD. Taking into account our conclusions and perspectives, we can make further progress in the treatment of BBR in NAFLD and NAFLD-related HCC.

Evaluation of calf thymus DNA binding of newly synthesize five 9 O Imidazolyl alkyl berberine derivative: A comparative multi-spectroscopic and calorimetric study

DNA binding with small molecule plays an important role in the designing of various anticancer drugs with greater efficacy. The five 9-O-imidazolyl alkyl berberine derivatives (BI) of different chain length has been synthesized and fully characterized. The binding study of calf thymus DNA with these newly synthesized berberine derivative was performed using various biophysical techniques. The binding affinity of BI to calf thymus DNA increased with increasing the chain length. The binding constant value obtained from UV-Vis spectral analysis was 1.84x105for BI1, 2.01x105for BI2, 1.51 × 106 for BI3, 3.66 × 106 for BI4, 6.68 × 106. Partial intercalative binding with strong stabilization of the DNA helix was revealed from circular dichroism spectral study and viscosity measurement. From the ITC experiment it was revealed that the bindings of BI1, BI2, BI3, BI4 and BI5 to calf thymus DNA were favoured by a large positive favourable entropy and negative enthalpy change and the highest spontaneity found for BI5. With the increase in chain length the binding was driven by a stronger entropy term with a higher binding constant indicates involvement of hydrophobic force for all these interaction. High binding affinities of calf thymus DNA with berberine-imidazole derivatives might be helpful for new drug design.

Structural modifications of berberine and their binding effects towards polymorphic deoxyribonucleic acid structures: A review

Berberine (BBR) is a plant derived quaternary benzylisoquinoline alkaloid, which has been widely used in traditional medicines for a long term. It possesses broad pharmacological effects and is widely applied in clinical. In recent years, the anti-tumor effects of BBR have attracted more and more attention of the researchers. The canonical right-handed double-stranded helical deoxyribonucleic acid (B-DNA) and its polymorphs occur under various environmental conditions and are involved in a plethora of genetic instability-related diseases especially tumor. BBR showed differential binding effects towards various polymorphic DNA structures. But its poor lipophilicity and fast metabolism limited its clinical utility. Structural modification of BBR is an effective approach to improve its DNA binding activity and bioavailability in vivo. A large number of studies dedicated to improving the binding affinities of BBR towards different DNA structures have been carried out and achieved tremendous advancements. In this article, the main achievements of BBR derivatives in polymorphic DNA structures binding researches in recent 20 years were reviewed. The structural modification strategy of BBR, the DNA binding effects of its derivatives, and the structure activity relationship (SAR) analysis have also been discussed.

Vegetable-derived indole enhances the melanoma-treating efficacy of chemotherapeutics

Food-drug interaction is an important but overlooked issue. For example, little is known concerning whether or not the chemotherapy of cancers is affected by the well-defined dietary chemicals such as 2-(indol-3-ylmethyl)-3,3'-diindolylmethane (LTr1) derived from daily consumed cruciferous vegetables. This work, inspired by the described melanogenesis reduction by certain indoles, presents that LTr1 mitigates the melanogenesis and thus potentiates the in vitro and in vivo anti-melanoma effectiveness of different chemotherapeutic agents including dacarbazine, vemurafenib, and sorafenib. In B16 melanoma cells, LTr1 was shown to inhibit the melanogenesis by acting towards the regulatory (R) subunit of protein kinase A (PRKAR1a) associated with the phosphorylation of cAMP-response element binding protein (CREB). This allows LTr1 to reduce the expression of melanogenesis-related enzymes such as tyrosinase (TYR), tyrosinase-related protein 1 (TYRP1), and tyrosinase-related protein 2 (TYRP2). Furthermore, LTr1 was addressed to bind to the aryl hydrocarbon receptor (AhR) and up-regulate the expression of CYP1A1 encoding cytochrome P450 1A1, leading to the escalation of reactive oxygen species (ROS) level. The increased ROS generation promotes the cysteine-to-cystine transformation to inhibit the pheomelanogenesis in melanomas. Collectively, the work identifies LTr1 as a new melanogenesis inhibitor that modulates the PKA/CREB/MITF and AhR/CYP1A1/ROS pathways, thereby providing a new option for (re)sensitizing melanomas to chemotherapeutics.

Inhibition of the Akt/NF-κB pathway is involved in the anti-gastritis effects of an ethanolic extract of the rhizome of Atractylodes macrocephala

ETHNOPHARMACOLOGICAL RELEVANCE

Gastritis can lead to ulcers and the development of gastric cancer. The rhizome of Atractylodes macrocephala Koidz. (Asteraceae), a traditional Chinese medicinal herb, is prescribed for the treatment of gastric disorders, hepatitis and rheumatism. Its bio-active compounds are considered to be particularly effective in this regard. However, the molecular processes of the herb's anti-inflammatory activity remain obscure. This study elucidates a mechanism upon which an ethanolic extract of this herb (Am-EE) exerts anti-inflammation effects in RAW264.7 macrophage cells (RAW cells) stimulated by lipopolysaccharide (LPS) treatment and HCl Ethanol-stimulated gastritis rats.

AIM OF THE STUDY

To investigate the anti-gastritis activities of Am-EE and explore the mode of action.

MATERIALS AND METHODS

Ethanol (95%) was used to prepare Am-EE. The quality of the extract was monitored by HPLC analysis. The in vivo effects of this extract were examined in an HCl Ethanol-stimulated gastritis rat model, while LPS-stimulated RAW cells were used for in vitro assays. Cell viability and nitric oxide (NO) production were observed by MTT and Griess assays. Real-time PCR was used to examine mRNA expression. The PGE₂ ELISA kit was employed to detect prostaglandin E₂ (PGE₂). Enzyme activities and protein contents were examined by immunoblotting. Luciferase reporter gene assays (LRA) were employed to observe nuclear transcription factor (NF)-κB activity. The SPSS (SPSS Inc., Chicago, Illinois, United States) application was used for statistical examination.

RESULTS

HPLC analysis indicates that Am-EE contains atractylenolide-1 (AT-1, 1.33%, w/w) and atractylenolide-2 (AT-2, 1.25%, w/w) (Additional Figure. A1). Gastric tissue damage (induced by HCl Ethanol) was significantly decreased in SD rats following intra-gastric application of 35 mg/kg Am-EE. Indistinguishable to the anti-inflammation effects of 35 mg/kg ranitidine (gastric medication). Am-EE treatment also reduced LPS-mediated nitric oxide (NO) and prostaglandin E₂ (PGE₂) production. The mRNA and protein synthesis of inducible cyclooxygenase (COX)-2 and NO synthase (iNOS) was down-regulated following treatment in RAW cells. Am-EE decreased NF-κB (p50) nuclear protein levels and inhibited NF-κB-stimulated LRA activity in RAW cells. Lastly, Am-EE decreased the up-regulated levels of phosphorylated IκBα and Akt proteins in rat stomach lysates and in LPS challenged RAW cell samples.

CONCLUSION

Our study illustrates that Am-EE suppresses the Akt/IκBα/NF-κB pathway and exerts an anti-inflammatory effect. These novel conclusions provide a pharmacological basis for the clinical use of the A. macrocephala rhizome in the treatment and prevention of gastritis and gastric cancer.

Berberine Protects against TNF-α-Induced Injury of Human Umbilical Vein Endothelial Cells via the AMPK/NF-κB/YY1 Signaling Pathway

Endothelial injury, characterized by an inflammatory response and increased permeability, is an initial stage of atherosclerosis (AS). Adenosine 5′-monophosphate (AMP), activated protein kinase (AMPK), and Nuclear Factor kappa B (NF-κB)/Yin Yang 1(YY1) signaling pathways play important roles in the process of endothelial injury. Berberine (BBR), a bioactive alkaloid isolated from several herbal substances, possesses multiple pharmacological effects, including anti-inflammatory, antimicrobial, antidiabetic, anticancer, and antioxidant activities. Previous studies showed a protective effect of berberine against endothelial injury. However, the underlying mechanism remains unclear. We explored the potential effect of BBR on TNF- (tumor necrosis factor-) α-induced injury of human umbilical endothelial cells (HUVECs) and studied its possible molecular mechanism. In the present study, HUVECs were divided into three groups. HUVEC viability was measured with Cell Counting Kit-8 assay. Extracellular lactic dehydrogenase (LDH) concentration was measured with LDH leakage assay. Endothelial microparticle (EMP) numbers were evaluated by flow cytometry analysis assay. The expression of proinflammatory cytokines was evaluated by Enzyme-Linked Immunosorbent Assay (ELISA). The mRNA expression of NF-κB and YY1 was detected by Real-Time PCR (RT-PCR). The protein expression of NF-κB, YY1, and AMPK was detected by immunofluorescence microscopy assay or western blot analysis. The results showed that LDH concentration, EMPs numbers, and the expression of proinflammatory cytokines (IL-6, IL-8, and IL-1β) increased in TNF-α-induced injured HUVECs, but ameliorated by BBR pretreatment. BBR pretreatment upregulated the expression of phosphorylated AMPK and downregulated the expressions of NF-κB and YY1 in injured HUVECs induced by TNF-α, which were offset by the AMPK inhibitor Compound C (CC). The results indicated that BBR protected against TNF-α-induced endothelial injury via the AMPK/NF-κB/YY1 signaling pathway.

Antifungal Activity of N-(4-Halobenzyl)amides against Candida spp. and Molecular Modeling Studies

Fungal infections remain a high-incidence worldwide health problem that is aggravated by limited therapeutic options and the emergence of drug-resistant strains. Cinnamic and benzoic acid amides have previously shown bioactivity against different species belonging to the Candida genus. Here, 20 cinnamic and benzoic acid amides were synthesized and tested for inhibition of C. krusei ATCC 14243 and C. parapsilosis ATCC 22019. Five compounds inhibited the Candida strains tested, with compound 16 (MIC = 7.8 µg/mL) producing stronger antifungal activity than fluconazole (MIC = 16 µg/mL) against C. krusei ATCC 14243. It was also tested against eight Candida strains, including five clinical strains resistant to fluconazole, and showed an inhibitory effect against all strains tested (MIC = 85.3–341.3 µg/mL). The MIC value against C. krusei ATCC 6258 was 85.3 mcg/mL, while against C. krusei ATCC 14243, it was 10.9 times smaller. This strain had greater sensitivity to the antifungal action of compound 16. The inhibition of C. krusei ATCC 14243 and C. parapsilosis ATCC 22019 was also achieved by compounds 2, 9, 12, 14 and 15. Computational experiments combining target fishing, molecular docking and molecular dynamics simulations were performed to study the potential mechanism of action of compound 16 against C. krusei. From these, a multi-target mechanism of action is proposed for this compound that involves proteins related to critical cellular processes such as the redox balance, kinases-mediated signaling, protein folding and cell wall synthesis. The modeling results might guide future experiments focusing on the wet-lab investigation of the mechanism of action of this series of compounds, as well as on the optimization of their inhibitory potency.

Glucocorticoid receptor-mediated alleviation of inflammation by berberine: in vitro, in silico and in vivo investigations

As a natural dietary ingredient, berberine possesses multiple biological activities including anti-inflammatory effects. In this work, glucocorticoid receptor (GR)-mediated alleviation of inflammation by berberine was investigated by a combination of in vitro, in silico, and in vivo approaches. The fluorescence polarization assay showed that berberine bound to GR with an IC₅₀ value of 9.14 ± 0.16 pM. Molecular docking and molecular dynamics simulation suggested that berberine bound stably to the active site of GR via hydrogen bonding and hydrophobic interactions. Berberine induced GR nuclear translocation but did not activate the glucocorticoid response element in HeLa cells. Furthermore, both gene and protein expressions of PEPCK were significantly attenuated by berberine in HepG2 cells. Interestingly, berberine downregulated CBG mRNA and protein levels without up-regulating TAT mRNA and protein levels in HepG2 cells, demonstrating its dissociated characteristics that could separate transrepression from transactivation. In addition, the in vitro and in vivo anti-inflammatory effects of berberine were confirmed in lipopolysaccharide-induced RAW 264.7 cells and in a mouse model of allergic contact dermatitis, respectively. In conclusion, berberine might serve as a potential selective GR modulator.

The anti-inflammatory effects of an ethanolic extract of the rhizome of Atractylodes lancea, involves Akt/NF-κB signaling pathway inhibition

ETHNOPHARMACOLOGICAL RELEVANCE

The dried rhizome of Atractylodes lancea (Thumb.) DC. (Compositae) has been prescribed in folk medicine for the management of various inflammatory conditions such as rheumatic diseases, gastritis and hepatitis. However, the molecular mechanisms underlying the beneficial properties of this herb remain elusive.

AIM OF THE STUDY

In this study, we investigated the anti-gastritis activities of Al-EE (an ethanolic extract of the herb) and explored the mechanism of action.

MATERIALS AND METHODS

An ethanolic extract of the Atractylodes lancea (Thumb.) DC. (Compositae) rhizome, Al-EE, was prepared with ethanol (95%) and quality controlled using HPLC analysis. To determine the in vivo effects of this extract, we utilised a HCl/EtOH-induced gastritis rat model. In vitro assays were carried out using a lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cell model. MTT assays were used to examine cell viability, while Griess assays were carried out to measure nitric oxide (NO) production. Messenger RNA expression was examined by real-time PCR. Prostaglandin E₂ (PGE₂) production was examined using ELISA assays. To examine protein expression and enzymatic activities, we employed western blot analysis. Nuclear transcription factor (NF)-κB activity was determined by Luciferase reporter assays.

RESULTS

The content of atractylenolide (AT)-1 and AT-2 in Al-EE was 0.45% and 5.07% (w/w), respectively (Supplementary Fig. 1). Al-EE treatment suppressed the production of NO and PGE₂, reduced the mRNA expression of inducible NO synthase (iNOS), cyclooxygenase (COX)-2 and tumor necrosis factor (TNF)-α, while also reducing the protein levels of iNOS and COX-2 in RAW264.7 macrophage cells. Furthermore, Al-EE inhibited the nuclear protein levels of NF-κB (p65) and NF-κB-driven luciferase reporter gene activity in RAW264.7 macrophage cells. Critically, intra-gastric injection of Al-EE (25 mg/kg) attenuated HCl/EtOH-induced gastric damage in SD rats, while the phosphorylation of Akt and IκBα was suppressed by Al-EE in vitro and in vivo.

CONCLUSION

In summary, Al-EE has significant anti-gastritis effects in vivo and in vitro, which can be associated with the inhibition of the Akt/IκBα/NF-κB signalling pathway. This mechanistic finding provides a pharmacological basis for the use of the A. lancea rhizome in the clinical treatment of various inflammatory conditions.

Integrated Transcriptomics and Reverse Pharmacophore Mapping-based Network Pharmacology to Explore the Mechanisms of Natural Compounds against Doxorubicin-induced Cardiotoxicity

BACKGROUND

Doxorubicin-induced cardiotoxicity (DIC) has greatly limited the clinical benefits of this frontline drug in oncotherapy. Drug combination with natural compounds (NCs) that possess potency against DIC is considered as a promising intervention strategy. However, the mechanisms of action (MoAs) underlying such drug interactions remain poorly understood. The aim of this study was to systematically pursuit of the molecular mechanisms of NCs against DIC.

METHODS

First, the gene expression signatures of DIC were characterized from transcriptomics datasets with doxorubicin-treated and untreated cardiomyocytes using differentially expressed gene identification, functional enrichment analysis, and protein-protein interaction network analysis. Secondly, reverse pharmacophore mapping-based network pharmacology was employed to illustrate the MoAs of 82 publicly reported NCs with anti-DIC potency. Cluster analysis based on their enriched pathways was performed to gain systematic insights into the anti-DIC mechanisms of the NCs. Finally, the typical compounds were validated using gene set enrichment analysis (GSEA) of the relevant gene expression profiles from a public gene expression database.

RESULTS

Based on their anti-DIC MoAs, the 82 NCs could be divided into four groups, which corresponded to ten MoA clusters. GSEA and literature evidence on these compounds were provided to validate the MoAs identified through this bioinformatics analysis. The results suggested that NCs exerted potency against DIC through both common and different MoAs.

CONCLUSION

This strategy integrating different types of bioinformatics approaches is expected to create new insights for elucidating the MoAs of NCs against DIC.

The Research on the Treatment of Metastatic Skin Cutaneous Melanoma by Huanglian Jiedu Decoction Based on the Analysis of Immune Infiltration Analysis

Objective

To explore the potential mechanism of Huanglian Jiedu Decoction (HJD) treatment and prevention of metastatic Cutaneous Melanoma (CM) occurrence and metastasis based on network pharmacological methods and immune infiltration analysis.

Methods

The GEO database was used to obtain metastatic CM disease targets, the TCMSP database and the HERB database were used to obtain HJD action targets, core genes were screened by protein interaction network, and the potential mechanism of HJD in the treatment of metastatic CM was explored by enrichment analysis, prognostic analysis and immune infiltration analysis.

Results

HJD treatment of metastatic CM involved 60 targets, enrichment analysis showed that HJD treatment of metastatic CM involved Chemokine signaling pathway, NF-kappa B signaling pathway, and Fluid shear stress and atherosclerosis, etc. Prognostic analysis revealed that HJD had a certain ability to improve the prognosis of metastatic CM patients. Immune infiltration analysis showed that HJD could inhibit the immune cell infiltration of metastatic CM patients by acting on related targets.

Conclusions

Our study identified the potential mechanism of HJD in the treatment of metastatic CM through network pharmacology, and revealed the mechanism of HJD in the prevention of Skin Cutaneous Melanoma metastasis through immune infiltration analysis and prognostic analysis.

Dauricine inhibits proliferation and promotes death of melanoma cells via inhibition of Src/STAT3 signaling

Melanoma is the most common type of skin cancer. Signal transducer and activator of transcription 3 (STAT3) signaling has been demonstrated to be a therapeutic target for melanoma. Dauricine (Dau), an alkaloid compound isolated from the root of Menispermum dauricum DC., has shown tumor-suppressing effects in multiple human cancers, but its potential in melanoma remains unexplored. In this study, we demonstrated that Dau significantly inhibited the viability and proliferation of A375 and A2058 melanoma cells. Death of melanoma cells was also markedly promoted by Dau. Moreover, Dau inhibited phosphorylation-mediated activation of STAT3 and Src in a dose-dependent manner. Notably, constitutive activation of Src partially abolished the antiproliferative and cytotoxic activities of Dau on melanoma cells. Molecular docking showed that Dau could dock on the kinase domain of Src with a binding energy of -10.42 kcal/mol. Molecular dynamics simulations showed that Src-Dau binding was stable. Surface plasmon resonance imaging analysis also showed that Dau has a strong binding affinity to Src. In addition, Dau suppressed the growth of melanoma cells and downregulated the activation of Src/STAT3 in a xenograft model in vivo. These data demonstrated that Dau inhibits proliferation and promotes cell death in melanoma cells by inhibiting the Src/STAT3 pathways.

Palmatine induces G2/M phase arrest and mitochondrial-associated pathway apoptosis in colon cancer cells by targeting AURKA

Studies have shown that palmatine (PAL) has anti-cancer effects. However, the activity and potential mechanisms of PAL against colorectal cancer remain elusive. The results showed that PAL significantly inhibited the proliferation of colon cancer cells in vitro and in vivo without significant effect on non-tumorigenic colon cells. Target prediction and clinical sample database analysis suggested that PAL may contribute to colon cancer cells phase arrest and apoptosis by targeting aurora kinase A (AURKA). Inhibition and overexpression of AURKA proved that PAL induces G2/M phase arrest and apoptosis in colon cancer cells by targeting AURKA. Moreover, PAL promoted intracellular Reactive oxygen species (ROS) production and decreased mitochondrial membrane potential (ΔΨm). PAL reduced the levels of AURKA, Bcl-xl and Bcl2 proteins, and promoted the expression of pro-apoptotic proteins P53, P73, Caspase3 and Caspase9, as well as the increase of cytochrome c (cyt. c) in cell lysates in vitro and in vivo. Together, our study confirmed that PAL induced G2/M phase arrest and mitochondrial-associated pathway apoptosis in colon cancer cells by targeting AURKA. PAL may provide a novel solution for the treatment of colon cancer by serving as a new AURKA inhibitor.

MDM2 inhibition-mediated autophagy contributes to the pro-apoptotic effect of berberine in p53-null leukemic cells

AIMS

Berberine (BBR) is reported to induce apoptosis and inhibit migration of leukemic cells, but the underlying pharmacological mechanisms have not been fully revealed. This study aims to investigate the possible mechanisms from the perspective of autophagy.

MAIN METHODS

P-53-null leukemic cell lines Jurkat and U937 were used for the in vitro study. MDC staining was used for observation of autophagy in leukemic cells, and Western blot analysis was for determination of the expression levels of autophagy-associated proteins. Apoptosis of the leukemic cells was detected by flow cytometry. Cellular location of MDM2 was observed with immunofluorescence staining. Ubiquitination of MDM2 was assessed by immunoprecipitation. Male 6-8-week-old NOD/SCID mice were used for evaluating the effect of BBR on chemotherapy sensitivity in vivo.

KEY FINDINGS

BBR induced autophagy in p53-null leukemic cells, which was inhibited by autophagy inhibitors 3-methyladenine. 3-methyladenine also inhibited BBR-induced apoptosis in leukemic cells. In addition, BBR not only decreased MDM2 mRNA expression, but also enhanced MDM2 self-ubiquitination in leukemic cells. Forced overexpression of MDM2 reversed the effect of BBR on autophagy and apoptosis. Furthermore, BBR promoted doxorubicin-induced autophagy and cell death in the leukemic cells and overexpression of MDM2 suppressed these effects. In vivo, BBR combined with doxorubicin achieved better therapeutic effect than doxorubicin alone.

SIGNIFICANCE

MDM2 inhibits autophagy and apoptosis in leukemic cells in a p53-independent manner. BBR induces autophagy in p53-null leukemic cells through downregulating MDM2 expression at both transcriptional and post-transcriptional levels, which may contribute to the anti-cancer effect of BBR in leukemia.

Coptidis Rhizoma: a comprehensive review of its traditional uses, botany, phytochemistry, pharmacology and toxicology

CONTEXT

Coptidis rhizome (CR), also known as Huanglian in Chinese, is the rhizome of Coptis chinensis Franch., C. deltoidea C.Y. Cheng et Hsiao, or C. teeta Wall (Ranunculaceae). It has been widely used to treat bacillary dysentery, diabetes, pertussis, sore throat, aphtha, and eczema in China.

OBJECTIVES

The present paper reviews the latest advances of CR, focusing on the botany, phytochemistry, traditional usages, pharmacokinetics, pharmacology and toxicology of CR and its future perspectives.

METHODS

Studies from 1985 to 2018 were reviewed from books; PhD. and MSc. dissertations; the state and local drug standards; PubMed; CNKI; Scopus; the Web of Science; and Google Scholar using the keywords Coptis, Coptidis Rhizoma, Huanglian, and goldthread.

RESULTS

Currently, 128 chemical constituents have been isolated and identified from CR. Alkaloids are the characteristic components, together with organic acids, coumarins, phenylpropanoids and quinones. The extracts/compounds isolated from CR cover a wide pharmacological spectrum, including antibacterial, antivirus, antifungal, antidiabetic, anticancer and cardioprotective effects. Berberine is the most important active constituent and the primary toxic component of CR.

CONCLUSIONS

As an important herbal medicine in Chinese medicine, CR has the potential to treat various diseases. However, further research should be undertaken to investigate the clinical effects, toxic constituents, target organs and pharmacokinetics, and to establish criteria for quality control, for CR and its related medications. In addition, the active constituents, other than alkaloids, in both raw and processed products of CR should be investigated.

All-Trans-Retinoic Acid Suppresses Neointimal Hyperplasia and Inhibits Vascular Smooth Muscle Cell Proliferation and Migration via Activation of AMPK Signaling Pathway

The proliferation and migration of vascular smooth muscle cells (VSMC) is extensively involved in pathogenesis of neointimal hyperplasia. All-trans-retinoic acid (ATRA) is a natural metabolite of vitamin A. Here, we investigated the involvement of AMP-activated protein kinase (AMPK) in the anti-neointimal hyperplasia effects of ATRA. We found that treatment with ATRA significantly reduced neointimal hyperplasia in the left common carotid artery ligation mouse model. ATRA reduced the proliferation and migration of VSMC, A7r5 and HASMC cell lines. Our results also demonstrated that ATRA altered the expression of proliferation-related proteins, including CyclinD1, CyclinD3, CyclinA2, CDK2, CDK4, and CDK6 in VSMC. ATRA dose-dependently enhanced the phosphorylation level of AMPKα (Thr172) in the left common carotid artery of experimental mice. Also, the phosphorylation level of AMPKα in A7r5 and HASMC was significantly increased. In addition, ATRA dose-dependently reduced the phosphorylation levels of mTOR and mTOR target proteins p70 S6 kinase (p70S6K) and 4E-binding protein 1 (4EBP1) in A7r5 and HASMC. Notably, the inhibition of AMPKα by AMPK inhibitor (compound C) negated the protective effect of ATRA on VSMC proliferation in A7r5. Also, knockdown of AMPKα by siRNA partly abolished the anti-proliferative and anti-migratory effects of ATRA in HASMC. Molecular docking analysis showed that ATRA could dock to the agonist binding site of AMPK, and the binding energy between AMPK and ATRA was -7.91 kcal/mol. Molecular dynamics simulations showed that the binding of AMPK-ATRA was stable. These data demonstrated that ATRA might inhibit neointimal hyperplasia and suppress VSMC proliferation and migration by direct activation of AMPK and inhibition of mTOR signaling.

An ethanol extract of the rhizome of Atractylodes chinensis exerts anti-gastritis activities and inhibits Akt/NF-κB signaling

ETHNOPHARMACOLOGICAL RELEVANCE

The rhizome of Atractylodes chinensis (DC.) kodiz (Compositae) has traditionally been used to treat inflammatory disorders such as arthritis and stomach ache, but scanted report has been issued on its anti-inflammatory mechanisms.

AIM OF THE STUDY

Here, we investigated the anti-gastritis activities and explored the mechanism of action of an ethanolic extract of the herb (Ac-EE).

MATERIALS AND METHODS

Ac-EE was prepared with 95% ethanol. To determine its in vivo effects, we employed an HCl/EtOH-induced gastritis rat model. We used a lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage model for in vitro assays. Griess and MTT assays were used to measure nitric oxide (NO) production and cell viability, respectively. We used real-time PCR to determine mRNA levels. To measure prostaglandin E₂ (PGE₂) production we used a PGE₂ EIA kit. To estimate protein levels and enzyme activities, we employed immunoblotting. Luciferase assays were used to examine nuclear transcription factor (NF)-κB activities.

RESULTS

Intragastric administration of Ac-EE (30 mg/kg) ameliorated HCl/EtOH-induced stomach tissue damages in SD rats. Ac-EE inhibited the levels of NO and PGE_2, down regulated mRNA and protein levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2. Ac-EE suppressed the nuclear level of NF-κB (p50), and inhibited NF-κB luciferase activity. The Phosphorylation of Akt and IκBα was also inhibited by Ac-EE both in vivo and in vitro.

CONCLUSION

Ac-EE treatment exerts an anti-gastritis effect in rats. Inhibition of the Akt/IκBα/NF-κB signaling pathway is associated with this effect, providing a pharmacological basis for the clinical application of the rhizome of A. chinensis in the treatment of inflammatory diseases.

The role of ginsenoside Rb1, a potential natural glutathione reductase agonist, in preventing oxidative stress-induced apoptosis of H9C2 cells

Background

Oxidative stress-induced cardiomyocytes apoptosis is a key pathological process in ischemic heart disease. Glutathione reductase (GR) reduces glutathione disulfide to glutathione (GSH) to alleviate oxidative stress. Ginsenoside Rb1 (GRb1) prevents the apoptosis of cardiomyocytes; however, the role of GR in this process is unclear. Therefore, the effects of GRb1 on GR were investigated in this study.

Methods

The antiapoptotic effects of GRb1 were evaluated in H9C2 cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, annexin V/propidium iodide staining, and Western blotting. The antioxidative effects were measured by a reactive oxygen species assay, and GSH levels and GR activity were examined in the presence and absence of the GR inhibitor 1,3-bis-(2-chloroethyl)-1-nitrosourea. Molecular docking and molecular dynamics simulations were used to investigate the binding of GRb1 to GR. The direct influence of GRb1 on GR was confirmed by recombinant human GR protein.

Results

GRb1 pretreatment caused dose-dependent inhibition of tert-butyl hydroperoxide-induced cell apoptosis, at a level comparable to that of the positive control N-acetyl-L-cysteine. The binding energy between GRb1 and GR was positive (−6.426 kcal/mol), and the binding was stable. GRb1 significantly reduced reactive oxygen species production and increased GSH level and GR activity without altering GR protein expression in H9C2 cells. Moreover, GRb1 enhanced the recombinant human GR protein activity in vitro, with a half-maximal effective concentration of ≈2.317 μM. Conversely, 1,3-bis-(2-chloroethyl)-1-nitrosourea co-treatment significantly abolished the GRb1's apoptotic and antioxidative effects of GRb1 in H9C2 cells.

Conclusion

GRb1 is a potential natural GR agonist that protects against oxidative stress–induced apoptosis of H9C2 cells.

Reverse Screening Methods to Search for the Protein Targets of Chemopreventive Compounds

This article is a systematic review of reverse screening methods used to search for the protein targets of chemopreventive compounds or drugs. Typical chemopreventive compounds include components of traditional Chinese medicine, natural compounds and Food and Drug Administration (FDA)-approved drugs. Such compounds are somewhat selective but are predisposed to bind multiple protein targets distributed throughout diverse signaling pathways in human cells. In contrast to conventional virtual screening, which identifies the ligands of a targeted protein from a compound database, reverse screening is used to identify the potential targets or unintended targets of a given compound from a large number of receptors by examining their known ligands or crystal structures. This method, also known as in silico or computational target fishing, is highly valuable for discovering the target receptors of query molecules from terrestrial or marine natural products, exploring the molecular mechanisms of chemopreventive compounds, finding alternative indications of existing drugs by drug repositioning, and detecting adverse drug reactions and drug toxicity. Reverse screening can be divided into three major groups: shape screening, pharmacophore screening and reverse docking. Several large software packages, such as Schrödinger and Discovery Studio; typical software/network services such as ChemMapper, PharmMapper, idTarget, and INVDOCK; and practical databases of known target ligands and receptor crystal structures, such as ChEMBL, BindingDB, and the Protein Data Bank (PDB), are available for use in these computational methods. Different programs, online services and databases have different applications and constraints. Here, we conducted a systematic analysis and multilevel classification of the computational programs, online services and compound libraries available for shape screening, pharmacophore screening and reverse docking to enable non-specialist users to quickly learn and grasp the types of calculations used in protein target fishing. In addition, we review the main features of these methods, programs and databases and provide a variety of examples illustrating the application of one or a combination of reverse screening methods for accurate target prediction.