Search

The present data showed that a natural compound isolated from the plant Physalis pubescens L. (Solanaceae), physapubescin B, exhibited antitumor activity against prostate cancer in vitro and in vivo. Treating prostate cancer cells with physapubescin B resulted in the accumulation of cells in the G2/M phase, which was associated with reduced Cdc25C levels and increased levels of CyclinB1, P21 as well as p-Cdk1 (Tyr15). Additionally, reactive oxygen species (ROS) generation was increased in physapubescin B-treated PC-3 cells. Furthermore, the physapubescin B-induced decrease of Cdc25C protein expression together with the G2/M phase cell cycle arrest were significantly abrogated by antioxidant NAC and GSH. Our data also demonstrated that physapubescin B exhibited strong in vivo antitumor efficacy in human prostate cancer PC3 xenograft. In conclusion, our results provide clear evidence that physapubescin B exhibits antitumor activity both in vitro and in vivo and deserves further development as an anticancer agent.

Ethnopharmacological Relevance: Dragon's blood has been used as a famous traditional medicine since ancient times by many cultures. It is a deep red resin, obtained from more than 20 different species of four distinct genera. Red resin of Dracaena cochinchinensis S.C. Chen, known as Chinese dragon's blood or Yunnan dragon's blood, has been shown to promote blood circulation, alleviate inflammation, and to treat stomach ulcers, diarrhea, diabetes, and bleeding. This study investigated an effective approach to identify natural therapeutic agents for neurodegeneration from herbal medicine. The dichloride extract and isolated effective constituents of Chinese dragon's blood showed quinone oxidoreductase 1 (NQO1) inducing activity and anti-inflammatory effect significantly, which are therapy targets of various neurodegenerative diseases., Materials and Methods: Multiple chromatography and spectra analysis were utilized to afford effective constituents. Then Hepa 1c1c7 and BV-2 cells were employed to assay their NQO1 inducing and anti-inflammatory activities, respectively., Results: Bioactivities guided isolation afforded 21 effective constituents, including two new polymers cochinchinenene E (1), cochinchinenene F (2) and a new steroid dracaenol C (16). The main constituent 3 (weight percent 0.2%), 5 (weight percent 0.017%), 4 (weight percent 0.009%), 9 (weight percent 0.094%), 10 (weight percent 0.017%) and 8 (weight percent 0.006%) are responsible for the anti-inflammatory activities of Chinese dragon's blood. While, new compounds 1, 2 and known compounds 5, 11 showed good NQO1 inducing activities. The brief feature of the activities and structures was discussed accordingly., Conclusion: Overviewing the bioactivities and phytochemical study result, 4'-hydroxy-2,4-dimethoxydihydrochalcone (3) and pterostilbene (5) as effective constituents of Chinese dragon's blood, were found to be potential candidate therapeutic agents for neurodegenerative diseases., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

In the present study, it was demonstrated that the dichloromethane extract of Physalis pubescens L. (DEPP) had weak potential quinone reductase (QR) inducing activity, but an UPLC-ESI-MS method with glutathione (GSH) as the substrate revealed that the DEPP had electrophiles (with an α,β-unsaturated ketone moiety). These electrophiles could induce quinone reductase (QR) activity, which might be attributed to the modification of the highly reactive cysteine residues in Keap1. Herein, four withanolides, including three new compounds physapubescin B (2), physapubescin C (3), physapubescin D (4), together with one known steroidal compound physapubescin (1) were isolated. Structures of these compounds were determined by spectroscopic analysis and that of physapubescin C (3) was confirmed by a combination of molecular modeling and quantum chemical DFT-GIAO calculations. Evaluation of the QR inducing activities of all withanolides indicated potent activities of compounds 1 and 2, which had a common α,β-unsaturated ketone moiety., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Affinity chromatography, applied to discover the enzyme inhibitors, needs special column with target protein and its carrier. Selection of stationary phase and mobile phase needs careful considerations due to the characteristics of proteins. In this study, a method immunoprecipitation (IP) coupled with HPLC-DAD-MS was developed to discover the aromatase ligands from Glycyrrhiza uralensis. An SB-C18 column was employed to separate target compounds without special consideration in mobile phase. Twenty-one compounds, including isolated compounds 4, 7, 8, 10, 11, 13, 15, 18-20, 23 and non-isolated compounds A-J, were found to have good affinity to aromatase by LC-MS. Seven of them (7, 15, 18, 19, 23, D, E) were detected to bind with aromatase in MCF-7 cells by IP coupled with HPLC-MS/MS. Bioassays disclosed aromatase inhibitory activities of the isolated compounds mentioned above, verifying the efficiency of IP coupled with HPLC-MS/MS as a method to screen aromatase ligands., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A new secoiridoid named chinensisol (1) along with twenty known compounds were isolated from the 95% ethanol extract of Cortex fraxini. Their structures were elucidated on the basis of NMR, MS, IR and UV spectral evidences. The quinone reductase (QR) inducing activities of the compounds were evaluated and the results showed that compounds 1, 9 and 14 had moderate QR inducing activities with CD values (concentration required to double the specific activity of QR) of 72.4 ± 7.7, 34.3 ± 3.3 and 42.0 ± 0.4 μM respectively., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Michael addition acceptors are considered as biologically active molecules, which regulate many signal pathways in cells. In the present study, it was demonstrated that the dichloromethane extract of Echinops grijisii had phase II detoxifying enzyme-inducing and nuclear factor-kappaB (NF-kappaB)-inhibiting activities, which might be attributed to the modification of key cysteine residues in Keap1 and NF-kappaB by Michael addition acceptors in it. To screen these Michael addition acceptors, glutathione (GSH) was employed, and a simple liquid chromatography-tandem mass spectrometry screening method was established to investigate the formation of GSH conjugates. Three thiophenes, 5-(penta-1,3-diynyl)-2-(3,4-diacetoxybut-1-ynyl)-thiophene (6), 2-(penta-1,3-diynyl)-5-(4-hydroxybut-1-ynyl)-thiophene (7), and 2-(penta-1,3-diynyl)-5-(3,4-dihydroxybut-1-ynyl)-thiophene (8) were demonstrated to react with GSH. Then NAD(P)H/quinone oxidoreductase1(NQO1) induction assay and an ultrafiltration mass spectrometric screening method were performed to investigate whether the above three compounds had NQO1-inducing and NF-kappaB (p65) alkylating activities. The result indicated that compounds 6-8, which had a common structural moiety, a penta-1,3-diynyl group, had strong NQO1-inducing activities, and compounds 7 and 8 could effectively alkylate the cysteine residues in NF-kappaB (p65).

Aromatase represents an important target for the treatment of hormone-dependent breast cancer. In the present study, nine alkaloids from the dichloromethane extract of Corydalis yanhusuo were identified by liquid chromatography tandem mass spectrometry (LC-MS/MS) and tested for their aromatase binding activities using an ultrafiltration LC-MS method by investigating the differences of peak areas of compounds before and after incubations with aromatase. It was demonstrated that the quaternary protoberberine alkaloids and the tertiary protoberberine alkaloids exhibited potent aromatase binding activities. The quaternary ammonium group and the methyl group at C-13 position of tertiary protoberberine alkaloids might be necessary for the activity. The findings should provide guidance for the discovery of potential aromatase inhibitors from natural products.

Four compounds, including one new lignan cavaol H (1), one new coumarinolignoid 5'-hydroxycleomiscosin B (4) and two known lignans (2-3) were isolated from the 95% ethanol extract of the twigs of Eurycorymbus cavaleriei. Their structures were established on the basis of various spectroscopic analyses including 1D-(1H, 13C, and DEPT) and 2D-NMR (COSY, HMQC, and HMBC). The absolute stereochemistry of the two known lignans was firstly reported in this article by 1H NMR studies on Mosher's ester derivatives. In the present study, quinone reductase induction activities of compounds 1-4 were assayed, compound 4 showed moderate quinone reductase induction with concentration to double the enzyme activity (CD) of 10.5 +/- 0.8 microg/mL. Then we established LC-MS-MS analysis of glutathione (GSH) incubation with compound 4 to explain whether compound 4 induced quinone reductase through alkylating of the sulfhydryl groups of Keap1. Reconstructed selected ion chromatogram (SIC) of m/z 706 after compound 4 incubation with GSH was different from that with Tris-HCl buffer solution, which meant the quinone reductase induction activity of compound 4 attributed to alkylating the sulfhydryl groups of Keap1.

In the present study, we examined the potential chemopreventive activity of dichloromethane extract of Eurycorymbus cavaleriei by investigating the change of constitutions after incubation with glutathione (GSH). The major constitutions in the dichloromethane extract of E. cavaleriei were cumarin compounds and their cleavage pattern was examined by LC-MS-MS and the characteristic product ions at m/z 206 and 207 were helpful to determine the substitutions of coumarinolignoid compounds. The mechanism of conjugations of 5'-demethylaquillochin and its isomer with GSH was discussed and validated through analysis of the conjugations of reference compound 6-hydroxy-7-methoxycoumarin with GSH by LC-MS-MS and NMR spectrum. The relative ability to induce the detoxification enzyme, NAD(P)H:quinone oxidoreductase 1 (NQO1) of nine coumarin compounds was tested which also showed 5'-demethylaquillochin exhibited the most potential chemopreventive ability. These observations suggest that 5'-demethylaquillochin and its isomer from the dichloromethane extract of E. cavaleriei have potential as chemopreventive agents through induction of detoxification enzymes.

Background: Motherwort has been used as medicinal herb for many years in both China and Europe. In particular, Chinese motherwort has been commonly used to treat disorders of mammary gland in Chinese traditional medicine (TCM). Chinese motherwort aqueous extract (MAE)was previously reported to have anti-cancer activity in breast cancer cells with low potency (IC50s in a range of 8-40 mg/mL). However, treatment of motherwort ethanol extract in vivo markedly suppressed the development of uterine adenomyosis and mammary cancers in mice. Therefore, anti-cancer activity of Chinese motherwort, especially in a form of ethanol extract, needs to be confirmed further at cellular level., Materials and Methods: Aerial part of Chinese motherwort (Leonurus japonicus Houtt) dry powder is extracted with 70% ethanol and the chemical components were characterized with HPLC finger print as well as mass spectrometry. Cytotoxicity of the motherwort aqueous ethanol extract (MAEE) was analyzed with MTT assay on ER negative MDA-MB-231 and ER positive MCF-7 human breast cancer cell lines. Hoechst 33342 staining and flow cytometry were used to verify whether the cell death induced by MAEE is apoptosis in nature. Cell cycle status of MAEE treated cells were analyzed with flow cytometry., Results: Our results showed that MAEE caused cell death in a dose-dependent and time-dependent fashion in both ER positive and negative breast cancer cells. Morphology, Hoechst 33342 staining and flow cytometry evidence all indicated the cell death is not in an apoptotic nature. Furthermore, low concentrations of MAEE caused cell cycle arrest at G2/M phase., Conclusions: These data suggest that Chinese motherwort aqueous ethanol extract may effectively inhibit the proliferation of breast cancer cells through mechanisms of both cytotoxicity and cell cycle arrest. The cellular effects of MAEE are non-apoptotic and ER independent on breast cancer cells.

The dichloromethane fraction of the crude ethanol extract of Echinops grijissi Hance roots exhibited different cytotoxicity against a panel of four human tumor cell lines, HepG2, K562, HL60 and MCF-7. By a bioassay-guided fractionation, eight thiophenes were isolated from the dichloromethane fraction, one of them was isolated from the plant for the first time. And they were assayed for their toxicity against the cell lines in order to compare their relative anti-tumor activity and find candidates of potential anti-tumor drugs. The dichloromethane fraction and isolated thiophenes showed different activity against the cell lines, and the anti-tumor activity of the dichloromethane fraction was also studied in vivo in S180 implanted ICR mice, however, it exhibited no anti-tumor activity at dosage of 20 or 40 mg/kg/d. There were also deaths recorded and the animals showed signs of toxicity when the dosage is 200 mg/kg/d.

Abstract: Litchi (Litchi chinensis Sonn.) is widely accepted as a delicious fruit in China and its seeds have been commonly used in traditional Chinese medicine to relieve neuralgic pain. In the present study, chemical investigation of the 95% ethanol extract of Litchi chinensis seeds led to the isolation of four new compounds, 2α,3α-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4β-8-catechin) (5), 2β,3β-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4α-8-epicatechin) (7), litchiol A (9) and litchiol B (12), together with 11 known ones, 2,5-dihydroxy-hexanoic acid (1), soscopoletin (2), coumaric acid (3), protocatechuic acid (4), 2α,3α-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4β−8)-epicatechin (6), pterodontriol d-6-O-β-d-glucopyranoside (8), Narirutin (10), naringin (11), dihydrocharcone-4′-O-β-d-glucopyranoside (13), pinocembrin-7-rutinoside (14), pinocembrin-7-neohesperidoside (15). Their structures were mainly elucidated on the basis of NMR, MS, IR, CD and UV spectral evidences. Antioxidant activities of 14 compounds were determined by DPPH radical-scavenging assay and Trolox equivalent antioxidant capacity assay, and the results showed that four compounds, protocatechuic acid (4), 2α,3α-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4β-8-catechin (5), 2α,3α-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4β−8)-epicatechin (6), 2β,3β-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4α-8)-epicatechin (7), exhibited moderate antioxidant activities. [ABSTRACT FROM AUTHOR]

Abstract: A new prenylated chalcone xanthohumol M (1), a novel prenylated bichalcone humulusol (2) and six known chalcones (3–8) were found from Humulus lupulus. Their structures were determined by spectroscopic methods. All the chalcones' electrophilic abilities were assessed by GSH (glutathione) rapid screening, and their QR (quinone reductase) induction activities were evaluated using hepa 1c1c7 cells. The results of electrophilic assay and QR induction activity assay were quite well. New compounds 1 and 2, along with some known prenylated chalcones, displayed certain QR induction activity. [Copyright &y& Elsevier]

Abstract: In the present study, it was demonstrated that the petroleum extract of Andrographis paniculata (AP) had quinone reductase (QR) inducing activity, which might be attributed to the modification of key cysteine residues in Keap1 by Michael addition acceptors (MAAs) in it. To screen MAAs in AP, glutathione (GSH) was employed, and a LC/MS/MS method was implied. Three compounds, andrographoside, andrographolide, 14-deoxy-14,15-dehydroandrographolide were revealed could well conjugated with GSH. Then, andrographolide along with 4 new and 14 known compounds were isolated to conduct QR induction evaluation, and the CD (the concentration required to double the activity of QR) value of andrographolide is 1.43μM. The QR induce activity of andrographolide might be attributed to its targeting multiple cysteine residues in Keap1, therefore, the alkylation of Keap1 by andrographolide was further studied and the result showed that four cysteine residues: Cys77, Cys151, Cys273 and Cys368 were alkylated, which indicated that Keap1 is a potential target for the QR induce activity of andrographolide. [Copyright &y& Elsevier]

Abstract: Michael reaction acceptors (MRAs) are a class of active molecules that are directly or indirectly involved in various cellular processes, including the regulation of many signaling pathways. In this study, the inducible nitric oxide synthase (iNOS) assay was used to demonstrate that the dichloromethane extract of Physalis alkekengi var. franchetii (DCEP) possesses anti-inflammatory activity that might be attributed to the modification of key cysteine residues in IKKβ by the MRAs in DCEP. To isolate these MRAs, glutathione (GSH) was employed, and a simple ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) screening method was developed to investigate the GSH conjugates with potential MRAs. Five physalins, including one new compound isophysalin A (2), together with four known steroidal compounds, physalin A (1), physalin O (3), physalin L (4) and physalin G (5), were isolated to evaluate the GSH conjugating abilities, and it was indicated that compounds 1, 2 and 3, which had a common α,β-unsaturated ketone moiety, exhibited conjugating abilities with GSH and also showed significant nitric oxide (NO) production inhibiting activities. The anti-inflammatory activities of compounds 1, 2 and 3 might be attributed to their targeting multiple cysteine residues on IKKβ; therefore, the alkylation of IKKβ by compound 1 was further studied by micrOTOF-MS. The result showed that six cysteine residues (C59, C179, C299, C370, C412, and C618) were alkylated, which indicated that IKKβ is a potential target for the anti-inflammatory activity of physalin A. [Copyright &y& Elsevier]

Abstract: A LC–MS method, which GSH was used as substrate, was employed to reveal the compounds with NQO1 induction activity from Angelica keiskei. Some compounds, proposed as isobavachalcone, xanthoangelol and 4-hydroxyderricin, have NQO1 induction activity. To make the actual structures and bioactivities of these compounds clear, 23 compounds, including above mentioned compounds and two new compounds 4-hydroxy-3,5,5-trimethyl-4-(1,2,3-trihydroxybutyl)cyclohex-2-enone (18) and (Z)-2-(3-hydroxypent-1-ynyl)-3-(non-1-enyl)oxiran-2-ol (23), were isolated from the 95% ethanol extract of A. keiskei. The bioassay results suggested the compounds had notable NQO1 induction activity. The radical scavenging and α-glucosidase inhibition activities of the isolated compounds were also tested. Compounds (E)-1-(2,4-dihydroxy-3-(3-methylbut-2-enyl)phenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one (1), (E)-1-(3-((E)-3,7-dimethylocta-2,6-dienyl)-2,4-dihydroxyphenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one (2), 1-(3-hydroxy-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[α]phenanthren-17-yl)ethanone (17), 4-hydroxy-3,5,5-trimethyl-4-(1,2,3-trihydroxybutyl)cyclohex-2-enone (18) could scavenge DPPH radical by more than 20%. Compounds (E)-1-(2,4-dihydroxy-3-(3-methylbut-2-enyl)phenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one (1), (E)-1-(3-((E)-3,7-dimethylocta-2,6-dienyl)-2,4-dihydroxyphenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one (2), (E)-1-(2-hydroxy-4-methoxy-3-(3-methylbut-2-enyl)phenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one (3), 7-hydroxy-6-(3-methylbut-2-enyl)-2H-chromen-2-one (5), 10-hydroxy-8,8-dimethyl-2-oxo-9,10-dihydropyrano[6,5-H]chromen-9-yl)-3-methylbut-2-enoate (9), 2-(4-hydroxyphenyl)-7-methoxy-8-(3-methylbut-2-enyl)-2,3-dihydrochromen-4-one (16), (10S,15R,Z)-10,15-dihydroxyheptadeca-8,16-dien-11,13-diynyl acetate (20), (3R,8S,Z)-heptadeca-1,9-dien-4,6-diyne-3,8-diol (21) exhibited excellent α-glucosidase inhibition activity. [Copyright &y& Elsevier]