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Novel withangulatin A (WA) derivatives were synthesized and evaluated for antiproliferative activity against four human cancer cell lines (U2OS, MDA-MB-231, HepG2, and A549). Among these derivatives, 10 exhibited the most potent antiproliferative activity, with an IC50 value of 74.0 nM against the human breast cancer cell line MDA-MB-231 and potency that was 70-fold that of WA (IC50 = 5.22 µM). Moreover, 10 caused G2-phase cell cycle arrest in a concentration-dependent manner and induced the apoptosis of MDA-MB-231 cells by increasing intracellular reactive oxygen species (ROS). Compound 10 showed a high selectivity index (SI = 267.03) for breast cancer MDA-MB-231 cells. These results suggest that 10 is a promising anticancer agent.

Eight new germacranolides, minusolides A-H (

The transcriptional repressor Snail trriggers epithelial-mesenchymal transition (EMT), the process allowing cancer cells with invasive and metastasis properties. In this study, we screened medicinal plants for the Snail inhibitory active components by high content screen (HCS) and found that the crude extract of Xylopia vielana leaves showed potential activity. Subsequently, bioassay-guided isolation of the extract of Xylopia vielana was performed to obtain twenty-four dimeric guaianes (1-24), including 16 new analogues (1-5, 8-11, 13-15, 17, 18, 21, and 22). Their structures were elucidated by the comprehensive application of multiple spectroscopic methods. Compounds 1, 11, 12, and 16 were initially identified as the active compounds. Wound healing assay, transwell migration assay and western blot experiments verified that compounds 1 and 12 inhibited the expression of Snail in a concentration-dependent manner, and compound 12 was verified as a potent tumor migration inhibitory agent. This work showed a practical strategy for the discovery of new Snail inhibitors from natural products and provided potential insights for dimeric guaianes as anticancer lead compounds specifically targeting Snail protein.

(±)-Patulignans A–C (1–3), three unique pairs of lignan enantiomers were isolated from the leaves of Melicope patulinervia. Patulignan A (1) possesses an unprecedented dimethyloxonane moiety in nature, meanwhile patulignans B (2) and C (3) are epimers carrying a novel dimethyl-1,6-dioxaspiro[4.5]decane skeleton. Their structures were established by spectroscopy methods and electronic circular dichroism (ECD) calculations. Compounds 1–3 showed significant inhibitory activity against α-glucosidase.

Taxodisones A and B, C30-terpenes with an unprecedented tetracyclo[12.4.0.0.2,709,14]octodecane core, were isolated from the seeds of Taxodium distichum. Their structures, including their configurations, were unambiguously determined. Their biomimetic synthesis suggests that they stem from diterpenes and monoterpenes, and not from squalene or oxidosqualene. In addition, their bioactivities were also evaluated.

(±)-Melipatulinones A-C (

Background Hepatic fibrosis is considered integral to the progression of chronic liver diseases, as it leads to the development of cirrhosis and hepatocellular carcinoma. The activation of hepatic stellate cells (HSCs) is the dominant event in hepatic fibrogenesis. The transforming growth factor-β1 (TGF-β1) and Yes-associated protein (YAP) pathways play a pivotal role in HSC activation, hepatic fibrosis and cirrhosis progression. Therefore, targeting the TGF-β/Smad and YAP signaling pathways is a promising strategy for antifibrotic therapy. Purpose The present study investigated the protective effects of Physalin D (PD), a withanolide isolated from Physalis species (Solanaceae), against liver fibrosis and further elucidated the mechanisms involved in vitro and in vivo. Study design/methods We conducted a series of experiments using carbon tetrachloride (CCl4)- and bile duct ligation (BDL)-induced fibrotic mice and cultured LX-2 cells. Serum markers of liver injury, and the morphology, histology and fibrosis of liver tissue were investigated. Western blot assays and quantitative real-time PCR were used to investigate the mechanisms underlying the antifibrotic effects of PD. Result PD decreased TGF-β1-induced COL1A1 promoter activity. PD inhibited TGF-β1-induced expression of Collagen I and α-smooth muscle actin (α-SMA) in human hepatic stellate LX-2 cells. PD significantly ameliorated hepatic injury, including transaminase activities, histology, collagen deposition and α-SMA, in CCl4- or BDL-induced mice. Moreover, PD markedly decreased the expression of phosphorylated Smad2/3 in vitro and in vivo. Furthermore, PD significantly decreased YAP protein levels, and YAP knockdown did not further enhance the effects of PD, namely α-SMA inhibition, Collagen I expression and YAP target gene expression in LX-2 cells. Conclusion These results clearly show that PD ameliorated experimental liver fibrosis by inhibiting the TGF-β/Smad and YAP signaling pathways, indicating that PD has the potential to effectively treat liver fibrosis.

It is significant to precisely isolate potential active compounds from medicinal herbs containing multiple compounds. Herein, a new strategy for precise separation of lysine-specific demethylase 1 (LSD1) inhibitors from the rhizome of Corydalis yanhusuo (RCY) using counter-current chromatography (CCC) guided by molecular docking and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) analysis was established. First, representative alkaloids from RCY were docked with LSD1 for screening active skeleton compounds. Simultaneously, the crude extract of RCY was preliminarily separated via pH-zone refining CCC. Subsequently, guided by LC-MS/MS analysis of the fragmentation pathways, three potential active fractions were obtained, followed by further online-storage and recycling CCC separation. Finally, three high-purity target quaternary alkaloids compound 3 (dehydrocorydaline), 7 (coptisine), and 8 (columbamine) were successfully isolated as a new class of potential natural LSD1 inhibitors by only one CCC instrument with multiple modes. Compound 3, with the highest LSD1 inhibition ratio of 2.44 μM, was tested for its ability to inhibit tumor invasion and metastasis in U2OS cells. Therefore, the CCC separation guided by virtual screening is a promising method for the targeted isolation of enzyme inhibitors from medicinal herbs.

Synephrine, a chiral adrenergic agonist, exists as R- (more active) and S-enantiomers (less active) that are difficult to separate because of their alkalinity and high polarity. Herein, we show that although this enantioseparation can hardly be achieved by high-performance liquid chromatography, acceptable preparative separation can be realized using high-speed counter-current chromatography (HSCCC) and pH-zone-refining counter-current chromatography (CCC) under optimal conditions. Specifically, 23.0 mg of S-synephrine and 25.0 mg of R-synephrine were isolated from 60.0 mg of racemic synephrine by conventional HSCCC, while 70.0 mg of S-synephrine and 69.0 mg of R-synephrine were obtained from 200.0 mg of racemic synephrine by pH-zone-refining CCC. The pH-zone-refining CCC was identified as the most efficient enantioseparation technique for synephrine and can be applied for the preparative enantioseparation of other β-amino alcohols.

Effective targeting of mitochondria has emerged as a beneficial strategy in cancer therapy. However, the development of mitochondria-targeting ligands is difficult because of the low permeability of the mitochondrial double membrane. We found that hypericin (HY), a natural product isolated from Hypericum perforatum L., is an effective mitochondria-targeting ligand. HY-functionalized graphene oxide (GO) loaded with doxorubicin (GO-PEG-SS-HY/DOX) increased the synergistic anticancer efficacy of phototherapy and chemotherapy in the absence of apparent adverse side effects. In vitro and in vivo assays suggested GO-PEG-SS-HY/DOX induced the expression of the key proteins of the mitochondria-mediated apoptosis pathway and caused apoptosis of breast carcinoma cells. In addition, GO vehicle exhibited low toxicity toward normal cells, indicating high safety of functionalized GO preparations in antitumor therapy. Therefore, HY-functionalized GO can be successfully used as a platform technology to target mitochondria in cancer cells and improve the therapeutic efficacy of chemotherapeutic drugs. Statement of Significance Induction of mitochondria-mediated apoptosis is a promising approach in cancer therapy. However, mitochondria are difficult to access and permeate because of their negative membrane potential and highly dense double membrane. Mitochondria-targeting ligands can be conjugated to nanoparticles or small-molecule drugs to enhance their antitumor effect. Here, we showed that the natural photosensitizer hypericin is a novel mitochondria-targeting ligand and that graphene oxide particles co-loaded with hypericin and the chemotherapeutic agent doxorubicin exhibited a synergistic antitumor effect mediated by the mitochondrial-mediated apoptosis. Treatment with such particles in combination with laser irradiation led to apoptosis of the tumor MDA-MB-231 and MCF-7 cells in vitro and in vivo. Furthermore, treatment with hypericin/doxorubicin-functionalized graphene oxide had low cellular toxicity.

γ-Glutamyltranspeptidase (GGT) plays critical roles in regulating various physiological/pathophysiological processes including the intracellular redox homeostasis. However, an effective fluorescent probe for dissecting the relationships between GGT and oxidative stress in vivo remains largely unexplored. Herein, we present a light-up fluorescent probe (DCDHF-Glu) with long wavelength emission (613 nm) for the highly sensitive and selective detection of GGT using dicyanomethylenedihydrofuran derivative as the fluorescent reporter and γ-glutamyl group as the enzyme-active trigger. DCDHF-Glu is competent to real-time image endogenous GGT in live cells and mice. In particular, DCDHF-Glu enables the direct real-time visualization of the upregulation of GGT under drug-induced oxidative stress in the HepG2 cells and the LO2 cells, as well as in vivo, vividly implying its excellent capacity in elucidation of GGT function in GGT-related biological events.

Peyronellones A and B (1 and 2), a pair of rare tetracyclic caged adducts of azaphilone with pyruvic acid, along with four new analogues (3–6), were isolated from solid cultures of the endophytic fungus Peyronellaea glomerata. Their structures were elucidated through spectroscopic analysis, and their absolute configurations were unambiguously determined by a combination of single-crystal X-ray crystallography, Rh2(OCOCF3)4-induced ECD experiments, ECD calculations, and modified Mosher methods. Compound 2 (5 μM) was found to have a significant hypoxia-protective effect that improved the survival rate of hypoxia/reoxygenation-treated human umbilical vein endothelial cells from 35% to 70%, which was equal to the potency of the positive control, verapamil. Flow cytometry analysis suggested 2 could inhibit H/R-induced late-stage apoptosis of this cell line.

The reactivity-based screening (RBS) was developed for directed discovery of cytotoxic withanolides. In this study, a thiol probe, 4-chlorobenzenethiol, was used to selectively attack cytotoxic withanolides containing potential pharmacophore, 2(3)-en-1-one in ring A (AEO) and 5β,6β-epoxy in ring B (BE), from the plant extract of Physalis angulata var. villosa. The screening was performed based on the potential mechanism of 4-chlorobenzenethiol nucleophilic addition to AEO, followed by detection of adducts using liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-Q-TOF-MS). Guided by RBS, eleven target withanolides, including five new compounds, physagulides R-V (10–14) and six known ones (2, 7–9, 15, 16) were discovered. All of them exhibited cytotoxicity against the both tested cell lines, especially, compounds 2, 7, 8 and 14 showed potent activities with IC50 values of 1.57–6.29 μM. The results suggested that RBS was efficient and accurate for rapid identification of cytotoxic withanolides and could guide isolation of target components from the complex medicinal plant extract.

Ten new highly oxidized monomeric (1–8) and dimeric guaianolides (9 and 10), along with two known guaianolide derivatives (11 and 12), were isolated from the aerial parts of Chrysanthemum indicum using a bioassay-guided fractionation procedure. The new compounds were characterized by the basic analysis of the spectroscopic data obtained, and the absolute configurations were determined by both empirical approaches and ECD calculations. Inhibitory effects of 1–12 on nitric oxide production were investigated in lipopolysaccaride (LPS)-mediated RAW 264.7 cells, and most of them (1–8 and 11) displayed IC50 values in the range 1.4–9.7 μM. Moreover, a mechanistic study revealed that the potential anti-inflammatory activity of compound 1 appears to be mediated via suppression of an LPS-induced NF-κB pathway and down-regulation of MAPK activation.

Biogenesis-inspired chemical research of the leaves of Taiwania cryptomerioides afforded four unprecedented dimeric diterpenes, featuring a tetracyclic [7. 75, 9. 4. 05, 10. 08, 9] octodecane core: taiwanoids A-D (1-4). The structures of these compounds were determined on the basis of comprehensive spectral analysis, chemical conversions and X-ray crystallography. A possible biosynthetic pathway for compounds 1-4 was proposed. Compounds 2 and 3 exerted a 5.37 and 6.26-fold potentiation effect on bortezmib (BTZ) susceptibility at a tested concentration of 20 μM, respectively.

Seven new phloroglucinol derivatives, uraliones L-R (1-7), were isolated from the whole plant of Hypericum urialum. The structures of new compounds were unambiguously elucidated by comprehensive spectroscopic analysis, and the absolute configurations of the vic-diol groups were determined by Mo2(OAc)4-induced electronic circular dichroism experiments. Their capability to reversal the multidrug resistance in doxorubicin-induced resistant MCF-7/DOX sublines showed that compounds 1, 5, 6, 7 exerted a potential effect of doxorubicin susceptibility.

// Xu-Wei Zhou 1, * , Yuan-Zheng Xia 1, * , Ya-Long Zhang 1 , Jian-Guang Luo 1 , Chao Han 1 , Hao Zhang 1 , Chao Zhang 1 , Lei Yang 1 and Ling-Yi Kong 1 1 Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China * These authors have contributed equally to this work Correspondence to: Lei Yang, email: dorothy19802003@gmail.com Ling-Yi Kong, email: cpu_lykong@126.com Keywords: tomentodione M; meroterpenoid; multidrug resistance; P-glycoprotein; p38 Received: July 02, 2017 Accepted: October 03, 2017 Published: October 19, 2017 ABSTRACT In this study, we investigated the mechanism by which tomentodione M (TTM), a novel natural syncarpic acid-conjugated monoterpene, reversed multi-drug resistance (MDR) in cancer cells. TTM increased the cytotoxicity of chemotherapeutic drugs such as docetaxel and doxorubicin in MCF-7/MDR and K562/MDR cells in a dose- and time-dependent manner. TTM reduced colony formation and enhanced apoptosis in docetaxel-treated MCF-7/MDR and K562/MDR cells, and it enhanced intracellular accumulation of doxorubicin and rhodamine 123 in MDR cancer cells by reducing drug efflux mediated by P-gp. TTM decreased expression of both P-gp mRNA and protein by inhibiting p38 MAPK signaling. Similarly, the p38 MAPK inhibitor SB203580 reversed MDR in cancer cells by decreasing P-gp expression. Conversely, p38 MAPK-overexpressing MCF-7 and K562 cells showed higher P-gp expression than controls. These observations indicate that TTM reverses MDR in cancer cells by decreasing P-gp expression via p38 MAPK inhibition.

Artemisians A-D (1-4), the first examples of [4 + 2] Diels-Alder type adducts presumably biosynthesized from a rare 1, 10-4, 5-diseco-guaianolide and a guaianolide diene, along with their possible precursor 5, were isolated from the traditional Chinese medicine Artemisia argyi. The structures of 1-4 were elucidated by extensive spectroscopic analyses and calculated electronic circular dichroism. Compound 2, with an IC50 value of 3.21 μM, exhibited significant antiproliferative activity via apoptosis induction and G2/M arrest in MDA-MB-468 cells.

Seven sucrose esters, physakengoses K-Q ( 1 – 7 ) were isolated from the aerial parts of Physalis alkekengi var. franchetii . Their structures were elucidated on the basis of extensive spectroscopic analyses and chemical methods. These new compounds were tested for their antimicrobial abilities against Staphylococcus aureus , Bacillus subtilis , Pseudomonas aeruginosa and Escherichia coli . Among the isolated sucrose esters, compounds 1 – 5 showed potent antibacterial activity with MIC values ranging from 2.16 to 12.76 μ g/mL.

Six novel calyxins, named calyxin T-W, ent-calyxin T and ent-calyxin U were isolated from the seeds of Alpinia katsumadai Hayata. Their relative configurations were elucidated by means of detailed UV, IR, NMR and MS spectroscopic data. Their absolute configurations were assigned by collaborative studies on single crystal X-ray diffraction analysis, Mosher's method, electronic circular dichroism (ECD), optical rotation and theoretical calculations. These compounds are Friedel-Cranft alkylation adducts composed of coexisted diarylheptanoids and flavanone from the seeds of Alpinia katsumadai. The antiproliferative activity of the six compounds against NCI-H460, HeLa, SMMC-7721 and HCT-116 cell lines was also reported, and most of them showed moderate to strong activities.

A pair of new tetranorlabdane diterpenoid epimers, named elettarins A (1) and B (2), together with five known labdane diterpenes (3–7), were isolated from Elettaria cardamomum Maton. The structures of elettarins A and B were established based on spectroscopic data (HRESIMS, 1D/2D NMR), and ECD experimentation. All isolates were evaluated for their inhibitory activities against nitric oxide (NO) production on BV-2 microglia cells.

Xylopiana A (1), a dimeric guaiane with an unprecedented pentacyclo[5.2.1.01,2.04,5′.05,4′]decane-3,2′-dione core, and three biosynthetically related intermediates, compounds 2–4, were isolated from the leaves of Xylopia vielana. Their structures and absolute configurations were determined by a combination of spectroscopic data, X-ray crystallography, electronic circular dichroism calculations, and chemical conversion. The structure of known vielanin A was revised to be compound 3. Compound 4 exerted a 3.7-fold potentiation effect on doxorubicin susceptibility at the tested concentration of 10 μM.

Application of NH2 silica gel column chromatography using CH2Cl2-MeOH was found to show a satisfactory resolution for separation of the crude resin glycosides of Pharbitis Semen (the seeds of Pharbitis nil), led to the isolation of seven new acylated glycosidic acid methyl esters, Pharesinosides A-G (1–7), along with four known ones (8–11). These compounds (1–11) were considered to be generated via methyl esterification of the carboxyl group in acylated glycosidic acids. Their structures including stereochemistry were elucidated on the basis of a combination of the spectroscopic and chemical methods. All isolates were evaluated for anti-tumor migration activities with human colon cancer cell line HCT-116, and compound 7 exhibited a potent migration inhibitory activity.

Seven azaphilones, montagnuphilones A–G (1–7), together with previously known azaphilones 8–11, were encountered in Montagnulaceae sp. DM0194, an endophytic fungus isolated from submerged roots of Persicaria amphibia. The structures of 1–7 were elucidated on the basis of their MS and NMR spectroscopic analysis. Compounds 1–8 were evaluated for their cytotoxicity and ability to inhibit nitric oxide (NO) production in lipopolysaccharide-activated RAW264.7 macrophage cells. Among these, none were found to be cytotoxic to RAW264.7 cells up to 100.0 μM, but 8, 5, and 2 showed NO inhibitory activity with IC50 values of 9.2 ± 0.9, 25.5 ± 1.1, and 39.6 ± 1.8 μM, respectively.

Tooniliatone A (1), a novel limonoid with an unprecedented 6/5/6/5 tetracarbocyclic skeleton was isolated from Toona ciliata Roem. var. yunnanensis. Its rearranged ring-seco backbone was proposed to biosynthetically originate from co-isolated known toonacilin (3) via a rare electron-deficient alkene electrophilic cyclization and 1,2-alkyl shift sequence. The acid-catalyzed biomimetic conversion of 3 not only successfully afforded 1 but also another novel 6/5/6/5 tetracarbocyclic skeleton, tooniliatone B (2). The priority of 2 in this biomimetic conversion, the existence of 1 and the absence of 2 in the crude extract suggested the biosynthetic selectivity of 1 from 3. The divergent biomimetic sequence, based on a carbocation from an epoxide moiety, provided an inspiration for constructing complex polycyclic carbon skeletons.

A new peroxide of xanthone ( 1 ), together with five analogues ( 2 – 6 ), was obtained from horseradish peroxidase (HRP) catalysed biotransformation of α -mangostin. In order to increase the yield of compound 1 , the environmental pH was succinctly adjusted, and as a result, compound 1 was formed with considerable selectivity. The anticancer potential of compound 1 , a pentacyclic xanthone with a 1,2-dioxolane ring, was investigated due to its potent cytotoxic activity. The results showed that apoptosis induced by compound 1 in human hepatocellular carcinoma (HepG2) cell was associated with activation of caspase-dependent apoptotic pathway, the generation of reactive oxygen species (ROS) and the activation of c-Jun N-terminal kinases (JNK). In summary, compound 1 with a peroxide group was biosynthesized in considerable yield through pH-switched biotransformation catalysed by HRP, which could be further developed as a promising candidate in the treatment of liver cancer.

An off-on fluorescent probe (CuCIN), coumarin-naphthol linked by an imine group, for detecting Cu2+ in DMSO-HEPES buffer (1:99, v/v) solution was successfully developed. Mechanism studies suggested that CuCIN firstly formed a complex with Cu2+ in a 1:2 metal-to-ligand ratio, and then 60-fold fluorescence enhancement was observed when Cu2+ promoted the imine hydrolysis to release the fluorescence compound 7-diethylaminocoumarin-3-aldehyde. This probe displayed desired properties such as high selectivity toward other metal ions, low detection limit (12.7 nM) and low cytotoxicity. Bio-imaging study revealed that the new probe CuCIN could be applied for imaging living cells with good cell permeability. We hope to apply this probe in the biomedical research field for the imaging of disease-relevant Cu2+.

Six new obovatol trimeric neolignans, houpulignans A–F (1–6) were isolated from the leaves of Magnolia officinalis var. biloba. Their structures were determined on the basis of the interpretation of HRESIMS, NMR data, and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 are the first examples of neolignans derived from three units of obovatol bearing a rare 1,4-benzodioxepane moiety. Compound 3 possesses a benzodihydropyran ring, meanwhile three units of obovatol in 4–6 are connected by an alkyl chain. Compounds 1–3 inhibited NO production in LPS-stimulated RAW264.7 cells with IC50 values of 8.01, 20.21, and 4.05 µM, respectively.

Therapeutic failure and drug resistance are common and have important implications in the poor prognosis of advanced breast cancer. It is necessary to acquire a natural product to overcome the resistance of cancer and increase the sensitivity of drug-resistant cells to anticancer agents.To demonstrate whether the compound Vielanin K (VK) has the potential to increase the sensitivity of MCF-7 and MCF-7/MDR cells to anticancer agents.Cell viability and proliferative capacity were determined by MTT, colony formation and EdU assays. Apoptosis and CaIn MCF-7 and corresponding MDR cells, VK increased the fluorescence intensity of Rho123, but not CFDA. VK treatment did not affect the protein expression of P-gp, MRP1 or BCRP. VK treatment enhanced the DOX-induced apoptotic cascade, while VK combined with DOX increased JNK phosphorylation by activating the IRE1α-TRAF2 signaling pathway. In addition, CaVK combined with DOX increases the apoptosis of MCF-7 and corresponding MCF-7/MDR cells by activating ER stress and mitochondrial apoptosis via IRE1α-TRAF2-JNK signaling.

In terms of ligand fishing, the amount and the relative activity recovery of enzymes immobilized on magnetic particles and nanoparticles are not preeminent. Therefore, the metal-organic framework (MOF) UiO-66-NH2 was synthesized to immobilize the porcine pancreatic lipase (PPL) via precipitation-cross-linking, and the resulting novel biological matrices named PPL@MOF manifested high PPL loading capacity (98.31 mg/g) and relative activity recovery (104.4%). Moreover, the novel enzyme-MOF composite was applied to screen lipase inhibitors from Prunella vulgaris L. to enrich and improve the techniques of ligand fishing. As a result, 13 lipase ligands were obtained, and 12 compounds were determined by HPLC-Q-TOF-MS/MS. All of these ligands were further confirmed to be potential inhibitors through the verification of the activity assay and molecular docking. The proposed approach based on PPL@MOF was superior in terms of abundant protein loading capacity, high enzyme catalytic activity and easy preparation process. Taken together, our newly developed method provided a new platform for efficient discovering bioactive molecules from natural herbs.

Two uncommon C

A synthesis-inspired chemical investigation of the leaves of Melicope ptelefolia led to the isolation of evodialones A–D (1–4), four rearranged acetophenone stereoisomers possessing a prenylated acylcyclopentenone skeleton with three stereogenic carbons. Evodialones C and D (3 and 4) are new minor constituents. The chiral-phase HPLC resolution gave (+)-1–4 and (−)-1–4, eight enantiomers forming a complete stereoisomer library. Their absolute configurations were elucidated via extensive spectroscopic data and a modified Mosher’s method. The relationship between the chiral structures and their NMR and ECD data is discussed. Compounds (±)-1, -2, and -4 have significant protective effects on high-glucose-induced oxidative stress in human vein endothelial cells.

The ability to separate bioactive compounds from herbal medicines, which contain abundant components, is crucial for drug discovery. Conventional Countercurrent chromatography (CCC) methods for separating bioactive compounds are labor intensive and show low efficiency. Here, we present a novel integrative CCC method for separating lysine-specific demethylase 1 (LSD1) inhibitors from the roots of Salvia miltiorrhiza (RSM). The methanol extracts of RSM were separated into hydrosoluble and liposoluble fractions, which were online stored in coils. Subsequently, the targeting LSD1 constituents were isolated using isocratic, gradient, or recycling elution mode. All separation processes could be accomplished using one CCC apparatus. Using our separation strategy, two phenylpropanoids and four tanshinones were isolated, which were determined to be new classes of natural LSD1 inhibitors. Salvianolic acid B, which showed the most potent inhibitory activity with an IC50 of 0.11 μM, exhibiting a considerable potential as an anticancer agent. Promisingly, the integrative CCC could be a crucial tool for the target separation of enzyme inhibitors from herbal medicines.

Nine new spirocyclic acylphloroglucinol derivatives, hyperpatulols A-I (1-9), were characterized from the flowers of Hypericum patulum. Their structures were elucidated by the basic analysis of the obtained spectroscopic data, and their absolute configurations were assigned by both the electronic circular dichroism (ECD) exciton chirality method and ECD calculation. The evaluation of their anti-migration effects on U2-OS human osteosarcoma cells showed that compound 4 exhibited moderate inhibitory activity in a dose-dependent manner. Further pharmacological studies revealed that 4 could regulate the expression of the proteins Vimentin and E-cadherin.

Pharbitidis Semen has worldwide recognition in traditional medicine for the treatment of several illnesses apart from its purgative properties, and it is also reported to show anticancer effect. However, limited pharmacological studies are available on the extract or resin glycosides fraction of Pharbitidis Semen. The purpose of this study was to determine the mechanism of the colon cancer cell cytotoxic effect of a purified resin glycoside fraction from Pharbitidis Semen (RFP). Our results showed that the RFP-induced cell death was mediated by the caspase-independent and autophagy-protective paraptosis, a type of cell death that is characterized by the accumulation of cytoplasmic vacuoles and mitochondria swelling. RFP significantly stimulated endoplasmic reticulum stress, inhibited proteasome-dependent degradation, and activated the MAPK signaling pathway in human colon cancer cell lines. Furthermore, we found that RFP activated chloride intracellular channel-1 (CLIC1) and increased the intracellular Cl− concentration. Blockage of CLIC1 by DIDS (disodium 4,4′-diisothiocyanato-2,2′-stilbenedisulfonate hydrate) attenuated cell death, cytoplasmic vacuolization, and endoplasmic reticulum stress, suggesting that CLIC1 acts as a critical early signal in RFP-induced paraptosis. In conclusion, results obtained indicated that the cytotoxic effect of RFP in colon cancer cells was the outcome of paraptosis mediated by activation of CLIC1.

Heat shock protein 90 (HSP90) is a chaperone protein that has been shown to regulate cancer progression. As a result, HSP90 has emerged as an attractive target for cancer therapy. Tubocapsenolide A (TA) is an anti-tumor component isolated from Tubocapsicum anomalum. Although the anti-tumor activity of TA was considered to be related to HSP90, the binding site and deep anti-tumor mechanisms still need to be elucidated. In this study, we found that TA is a covalent inhibitor of HSP90, which inhibits HSP90 ATPase activity without blocking ATP binding. Further studies indicated that TA targets the C-terminal Cys521 site, which led to HSP90 partial oligomerization and hindered its anti-aggregation and refolding activity. The damage of the chaperone activity disrupted the interaction between HSP90 and its cochaperone CDC37 as well as its client proteins, thereby inducing cell cycle arrest and apoptosis. Moreover, TA was found to have therapeutic effects on the xenograft tumor model by inducing the degradation of HSP90 client proteins. Together, our results identified HSP90 as the direct target of TA for mediating the anti-tumor activity. TA could serve as a lead compound for developing novel HSP90 C-terminal covalent inhibitors with binding site different from the ATP-binding domain.

Taxodinoid A (1), an unprecedented bis-diterpenic anhydride featuring a 6/6/7/6/6/6 heptacyclic core skeletons, and three novel pyrane-fused abietane-type diterpene dimers (2–4), were obtained from the seeds of Taxodium distichum. Their structures were elucidated by spectroscopic data, X-ray crystallograph and electronic circular dichroism calculation. A biosynthetic pathway and suppressing migration activity against U2 OS cells were also discussed.

To develop novel GLS1 inhibitors as effective therapeutic agents for triple-negative breast cancer (TNBC), 25 derivatives were synthesized from the natural inhibitor withangulatin A (IC50 = 18.2 μM). Bioassay optimization identified a novel and selective GLS1 inhibitor 7 (IC50 = 1.08 μM). In MDA-MB-231 cells, 7 diminished cellular glutamate levels by blocking glutaminolysis pathway, further triggering the generation of reactive oxygen species to induce caspase-dependent apoptosis. Molecular docking indicated that 7 interacted with a new reacting site of allosteric binding pocket by forming various interactions in GLS1. The intraperitoneal administration of 7 at a dose of 50 mg/kg exhibited remarkable therapeutic effects and no apparent toxicity in the MDA-MB-231 xenograft model, indicating its potential as a novel GLS1 inhibitor for treatment of TNBC.

Four new lignans, patulinones A−D (1–4) and three new acetophenone derivatives, patulinones E−G (5–7) were isolated from the leaves of Melicope patulinervia. Their structures were elucidated on the basis of the interpretation of HR-ESIMS, NMR, CD data. All the isolated compounds were evaluated for α-glucosidase inhibitory activity. Of the isolates, compound 4 was found to exhibit the strongest inhibition against α-glucosidase with IC50 value of 6.02 ± 0.46 μM.

Tow new arylalkenyl α,β-unsaturated δ-lactones named cryptoconcatones K (1) and L (2) were obtained from the leaves and twigs of Cryptocarya concinna. Their structures were established on the basis of spectroscopic data (MS, 1D and 2D NMR). Compounds 1 and 2 showed cytotoxic activities with IC50 values of 4.5 and 3.9 μM against Huh7 cancer cell line, respectively.

Cu(II) complexed amino acid ionic liquid, Cu(II)-[1-butyl-3-methylimidazolium][L-Pro] (Cu(II)-[BMIm][L-Pro]), was successfully adopted as chiral ligand to improve the enantioseparation efficiency in high speed counter-current chromatography (HSCCC). For the enantioseparation of intractable naringenin (NRG) racemic mixtures, Cu(II)-[BMIm][L-Pro] coupled with hydroxypropyl-β-cyclodextrin (HP-β-CD) was successfully applied as dual chiral selectors in HSCCC. The influence of important parameters, including the concentration of the chiral selectors, the pH value, and the temperature were investigated. Under optimal conditions, 4.5mg of (+)-NRG and 4.1mg of (-)-NRG were successfully separated from 10mg NRG racemic mixtures with the purity of 98%. The chiral recognition mechanism of dual chiral selectors was illuminated by the UV-vis and NMR spectra, suggesting that the enantioseparation was upon the difference of the thermodynamic stability of the quaternary complexes of Cu(II), [BMIm][L-Pro], HP-β-CD, and NRG. The results illustrated that the developed HSCCC system, based on the synergistic mechanism of Cu(II)-[BMIm][L-Pro] and HP-β-CD, exhibited better performance on enantioseparation and had great application potential in preparative chiral separation of natural products.

Seven new cadinane-type sesquiterpenoids (1–7) were isolated from the rhizomes of Stahlianthus involucratus. The planar structures of 1–7 were elucidated on the basis of extensive spectroscopic and HRMS data. The absolute configuration of 1 was determined by the single-crystal X-ray diffraction, whereas those of C-9 in 3, C-9 in 4, C-6 in 6, and the 1,2-diol in 7 were deduced via the CD data of the in situ formed [Rh2(OCOCF3)4] complex, and Mo2(OAc)4-induced CD analysis, respectively.

Ten new (1-10) and seventeen known (11-27) neo-clerodane diterpenoids substituted with nicotinoyloxyl were isolated from the plant Scutellaria barbata and their structures were established by extensive spectroscopic analysis. Chemoreversal effects of these neo-clerodane diterpenoids on multidrug resistance were evaluated in breast cancer multidrug-resistant MCF-7/ADR cells that overexpress P-glycoprotein. Four compounds (11, 14, 16, and 18) exhibited better chemoreversal abilities than the classical P-gp inhibitor verapamil and the most potent compound 11 reduced IC50 value of adriamycin in MCF-7/ADR cells from 58.8 μM to 1.3 μM. Mechanistic investigations showed that compound 11 reversed multidrug resistance through suppressing the activity of P-gp and restraining the expression of P-glycoprotein. In the present study, the structure-activity relationships of neo-clerodane diterpenoids were also discussed.

Ten new sucrose esters, physakengoses A-J (1-10), were isolated from the aerial parts of Physalis alkekengi var. franchetii under the guidance of 1H NMR spectroscopy. Their structures were determined by spectroscopic analyses (HRESIMS, 1D and 2D NMR, and ESIMS) and chemical methods. These new compounds were tested for antibacterial activities against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa and Escherichia coli. Among them, compounds 2 and 5-8 showed potent inhibitory effects against test strains with MIC values ranging from 3.5 to 14.9μg/mL. These findings may indicate that the P. alkekengi var. franchetii has potential application as an ingredient in pharmaceuticals.

Rhodomyrtials A and B (1 and 2), two unprecedented triketone-sesquiterpene-triketone adducts, along with five biogenetically related intermediates, rhodomentone A (3) and tomentodiones A-D (4-7), were isolated from the leaves of Rhodomyrtus tomentosa. Their structures and absolute configurations were determined by a combination of NMR spectroscopy, chemical conversion, and X-ray diffraction analysis. Compounds 1 and 2 were biomimetically synthesized via 5 and 4, respectively, rather than 3, revealing their key ordering of biosynthetic events and confirming their structural assignments. Compound 7 exhibited potent metastatic inhibitory activity against DLD-1 cells by suppressing the activation of matrix metalloproteinase (MMP)-2 and MMP-9.

A biphasic chiral recognition system based on chiral ligand exchange with Cu(II)-N-n-dodecyl-L-proline and hydroxypropyl-β-cyclodextrin as an additive was developed to enantioseparate aromatic β-amino acids by high-speed counter-current chromatography. The biphasic chiral recognition system was established with an n-butanol/water (1:1, v/v) solvent system by adding N-n-dodecyl-L-proline and Cu(II) ions to the organic phase and hydroxypropyl-β-cyclodextrin to the aqueous phase. Several separation parameters, such as temperature, pH value, and chiral selector concentration, were systematically investigated by enantioselective liquid-liquid extraction. Under the optimal separation conditions, 54.5 mg of (R,S)-β-phenylalanine and 74.3 mg of (R,S)-β-3,4-dimethoxyphenylalanine were baseline enantioseparated. More importantly, the synergistic enantiorecognition mechanism, based on the Cu(II)-N-n-dodecyl-L-proline and hydroxypropyl-β-cyclodextrin, was discussed for the first time.

Lycodine-type alkaloids have gained significant interest owing to their unique skeletal characteristics and acetylcholinesterase activity. This study established a rapid and reliable method using ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-Q/TOF-MS/MS) for comprehensive characterization of lycodine-type alkaloids for the first time. The lycodine-type alkaloids were detected successfully from Lycopodiastrum casuarinoides, Huperzia serrata and Phlegmarirus carinatus in seven plants of the Lycopodiaceae and Huperziaceae families, based on the established characteristic MS fragmentation of five known alkaloids. Furthermore, a total of 13 lycodine-type alkaloids were identified, of which three pairs of isomers were structurally characterized and differentiated. This study further improves mass analysis of lycodine-type alkaloids and demonstrates the superiority of UPLC with a high-resolution mass spectrometer for the rapid and sensitive structural elucidation of other trace active compounds. Copyright © 2016 John Wiley & Sons, Ltd.

// Chao Zhang 1 , Lei Yang 1 , Ya-di Geng 1 , Fa-liang An 1 , Yuan-zheng Xia 1 , Chao Guo 1 , Jian-guang Luo 1 , Lu-yong Zhang 1 , Qing-long Guo 1 , Ling-yi Kong 1 1 State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, China Correspondence to: Ling-yi Kong, e-mail: cpu_lykong@126.com Keywords: Icariside II, aberrant energy homeostasis, glycolysis, mRNA translation, mTORC1-4E-BP1 axis Received: July 20, 2015 Accepted: March 23, 2016 Published: April 1, 2016 ABSTRACT The aberrant energy homeostasis that characterized by high rate of energy production (glycolysis) and energy consumption (mRNA translation) is associated with the development of cancer. As mammalian target of rapamycin (mTOR) is a critical regulator of aberrant energy homeostasis, it is an attractive target for anti-tumor intervention. The flavonoid compound Icariside II (IS) is a natural mTOR inhibitor derived from Epimedium. Koreanum . Herein, we evaluate the effect of IS on aberrant energy homeostasis. The reduction of glycolysis and mRNA translation in U2OS (osteosarcoma), S180 (fibrosarcoma) and SW1535 (chondrosarcoma) cells observed in our study, indicate that, IS inhibits aberrant energy homeostasis. This inhibition is found to be due to suppression of mammalian target of rapamycin complex 1 (mTORC1)-eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) axis through blocking the assembly of mTORC1. Furthermore, IS inhibits the cap-dependent translation of c-myc through mTORC1-4E-BP1 axis which links the relationship between mRNA translation and glycolysis. Inhibition of aberrant energy homeostasis by IS, contributes to its in vitro and in vivo anti-proliferation activity. These data indicate that IS disrupts aberrant energy homeostasis of sarcoma cells through suppression of mTORC1-4E-BP1 axis, providing a novel mechanism of IS to inhibit cell proliferation in sarcoma cells.

Bidens pilosa is used as a functional food and a traditional Chinese medicine to treat hypertensive disease. In this study, based on a bioactivity-guided fractionation of renin- and angiotensin I-converting enzyme (ACE)-inhibitory activities, a method of liquid chromatography–mass spectrometry (LC–MS)-based chemometrics analysis was used to identify bioactive compounds from the ethanol extract of B. pilosa . Polyphenol-containing fraction exhibited the highest dual inhibitions towards renin and ACE activities. A total 18 marker metabolites were positively or tentatively identified by LC–MS/MS, five of which contributed most to distinguishing between active and inactive portions and were confirmed to possess in vitro dual inhibitory activities against renin and ACE. This is the first study to demonstrate the active constituents of B. pilosa for dually regulating the renin–angiotensin system (RAS) in vitro . This established method represents a rapid and effective method for the identification of bioactive compounds from functional foods and nutraceuticals.

Two new polycyclic polyprenylated acylphloroglucinols, attenuatumione G (1) and attenuatumione H (2), together with five known compounds (3–7) have been isolated from the whole plant of Hypericum attenuatum. Their structures were elucidated by spectroscopic data including HRESIMS, 1D- and 2D-NMR. In biological assays, compound 2 showed moderate cytotoxic activities against Hep-G2 (IC50 9.11 μM) and MCF-7 (IC50 16.24 μM), compound 4 exhibited significant cytotoxic activity with IC50 value of 5.32 μM against Hep-G2, and both compounds 5 and 6 revealed significant nitric oxide production inhibitory activity with IC50 values of 5.52 and 8.46 μM, respectively.