3-O-(E)-p-coumaroyl tormentic acid from Eriobotrya japonica leaves induces caspase-dependent apoptotic cell death in human leukemia cell line

Eleven triterpene acids, 1-11, isolated from the leaves of Eriobotrya japonica, were evaluated for inhibition of DNA topoisomerase (Topo) I and cytotoxicity against human leukemia (HL60) and melanoma cell lines (CRL1579). Among the compounds tested, four compounds, δ-oleanolic acid (4), ursolic acid (5), 3-O-(E)-p-coumaroyl tormentic acid (8), and betulinic acid (10), exhibited potent Topo I inhibitory activity (IC(50) 20.3-36.5 μM) and cytotoxicity against HL60 (EC(50) 5.0-8.1 μM). Upon assessing the apoptosis-inducing activity in HL60 cells, compound 8 exhibited induction of apoptosis detected by the observation of DNA fragmentation and membrane phospholipid exposure in flow cytometry. Western blot analysis showed that compound 8 markedly reduced the levels of procaspases-3 and 9, while being increased the levels of cleaved caspases-3 and 9. On the other hand, compound 8 exerted almost no influence on the expression of caspase-8. In addition, compound 8 increased significantly Bax/Bcl-2 ratio and activated caspase-2. These results suggested that compound 8 induced apoptotic cell death in HL60 via mainly mitochondrial pathway by, at least in part, Topo I inhibition. Therefore, compound 8 may be promising lead compound for developing an effective drug for treatment of leukemia.     

Dicarba-closo-dodecaboranes as a pharmacophore. Novel potent retinoidal agonists.

The synthesis and biological evaluation of the dicarba-closo-dodecaborane (carborane) derivatives of retinoids are described. Retinoidal activity was examined in terms of the differentiation-inducing ability toward human promyelocytic leukemia HL-60 cells. High retinoidal activity (agonist or antagonist for the retinoid receptor RAR) requires a carboxylic acid moiety and an appropriate hydrophobic group located at a suitable position on the molecule. 4-[4-(1,2-Dicarba-closo-dodecaboran-1-yl)phenylamino]b enzoic acids and 4-[3-(1,2-dicarba-closo-dodecaboran-1-yl)phenylamino]b enzoic acids showed potent agonistic activity at concentrations of 10(-8)-10(-9) M. The results indicate that carboranes are applicable as the hydrophobic moiety of biologically active molecules.     

Cytotoxic and anti-oxidant activities of lanostane-type triterpenes isolated from Poria cocos

A new lanostane-type triterpene, 29-hydroxypolyporenic acid C (8), was isolated from the dried sclerotia of Poria cocos together with eight other known compounds pachymic acid (1), dehydropachymic acid (2), 3-acetyloxy-16alpha-hydroxytrametenolic acid (3), polyporenic acid C (4), 3-epi-dehydropachymic acid (5), 3-epi-dehydrotumulosic acid (6), tumulosic acid (7), and dehydrotumulosic acid (9). The compounds were identified by spectral analysis and comparison with spectroscopic data reported in the literatures. Although none of the nine (1 to 9) compounds showed promising antioxidant activity, 1 through 6 and 8 showed good cytotoxicity against human lung cancer cell line A549 and human prostate cancer cell line DU145. Interestingly, all these compounds exhibited better cytotoxicity towards A549 than DU145 cells.     

Schiff bases of indoline-2,3-dione (isatin) with potential antiproliferative activity

ABSTRACT: BACKGROUND: Cancer is one of the most dreaded diseases and it is a leading cause of mankind death worldwide. Recent reports documented a remarkable antiproliferative activity of isatin nucleus against various cancer cell lines. The current work describes the antiproliferative activity of Schiff bases of combinatorial mixtures of the isatin derivatives M1-M22 as well as the individual compounds 1-11(A-K) of these combinatorial mixtures. RESULTS: The designed combinatorial library composed from eleven hydrazides A-K and eleven isatin derivatives 1-11 has been synthesized to formally generate 22 mixtures, M1-M22 of 121 Schiff bases, and their antiproliferative activity against K562 chronic myelogenous leukemia cells was evaluated. The indexed method of analysis of the prepared library was applied to elucidate the active components in the tested mixtures M1-M22. The predictions from the crossing procedure was validated through evaluation of the antiproliferative activity of individual compounds 1-11(A-K) of the library. Individual compounds 1-11(A-K) were also evaluated against the non-tumorigenic MCF-12A cell line to investigate their selectivity. A pharmacophore model was developed to further optimize the antiproliferative activity among this series of compounds. CONCLUSIONS: Variable antiproliferative activity was revealed with the investigated mixtures M1-M22 and the individual compounds 1-11(A-K). Most of the tested mixtures and several individual Schiff bases displayed high potency with IC50 values in the low micromolar range. A considerable selectivity of some individual compounds to the tumorigenic K562 cell line compared with the non-tumorigenic MCF-12A cell line was observed as indicated by their selectivity index (SI).     

Effects of immunomodulatory derivatives of thalidomide (IMiDs) and their analogs on cell-differentiation, cyclooxygenase activity and angiogenesis

Various analogs of known immunomodulatory derivatives of thalidomide (1) (IMiDs: 3, 5) were synthesized, focusing on cell-differentiation-inducing, cyclooxygenase-inhibitory and anti-angiogenesis activities. Among the prepared compounds, NIDO-33 (14) showed cell differentiation-inducing activity on HL-60 cells and anti-angiogenic activity on human umbilical vein endothelial cells (HUVEC). AIDO-00 (7) also showed anti-angiogenic activity. NIDO-11 (8) showed an enhancing effect on all-trans retinoic acid (ATRA)-induced HL-60 cell differentiation, and AIDO-30 (13) exhibited cyclooxygenase (COX)-inhibitory activity.     

Bioactivity-guided study of antiproliferative activities of Salvia extracts

The cytotoxic activities of the n-hexane, chloroform and aqueous methanolic fractions prepared from the methanolic extract of the leaves of 23 Salvia taxa were studied for their cell growth-inhibitory activity against human cervix adenocarcinoma (HeLa), skin carcinoma (A431) and breast adenocarcinoma (MCF7) cells using the MTT assay. The n-hexane fractions of six Salvia taxa (S. hispanica, S. nemorosa, S. nemorosa 1. albiflora, S. pratensis, S. recognita and S. ringens) and the chloroform fraction ofS. officinalis 1. albiflora produced over 50% growth inhibition of the skin carcinoma cell line. None of the tested extracts showed substantial (above 50%) antiproliferative effects against HeLa and MCF7 cells. S. ringens was the most powerful among the studied Salvia species with a 61.8% cell growth inhibitory activity on A431 cells. In the case of S. ringens, other plant parts were also tested for antiproliferative effect, and the highest activities were recorded for the root extract. This was subjected to bioactivity-guided fractionation, which yielded four abietane diterpenes (royleanone, horminone, 7-O-methyl-horminone and 7-acetyl-horminone), one triterpene (erythrodiol-3-acetate) and beta-sitosterol. Horminone, 7-acetyl-horminone and erythrodiol-3-acetate displayed marked concentration-dependent antiproliferative effects, while royleanone and 7-O-methyl-horminone produced weaker activities.     

Induction of differentiation of human leukemia cells by various combinations of cytokines and low-molecular-weight inducers

To explore agents for differentiation therapy of leukemias, various combinations of cytokines and low-molecular-weight inducers were examined for differentiation-inducing activity toward three kinds of human leukemia-derived cell lines. The strongest differentiation inducing activity on promyelocytic HL60 cells and histiocytic U937 cells was obtained by combining recombinant tumor necrosis factor (rTNF), interferon-gamma (IFN-gamma), retinoic acid (RA), and 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25(OH)2D3). For myeloblastic ML1 cells, the combination of rTNF, IFN-gamma, and RA had the strongest differentiation-inducing activity.     

Hypericin-induced photocytotoxicity is connected with G2/M arrest in HT-29 and S-phase arrest in U937 cells

Susceptibility of the HT-29 human colon adenocarcinoma cell line and human myeloid leukemia cell line U937 to hypericin-mediated photocytotoxicity was investigated and compared in this study. Cellular parameters as viability, cell number, metabolic activity and total protein amount were monitored in screening experiments with subsequent cell-cycle analysis and apoptosis detection to determine the cellular response of the different tumor types to various concentrations of photoactivated hypericin. The results show concentration dependence of the photosensitizer's cytotoxicity on the studied cell lines, with higher sensitivity of U937 cells. Whereas the two extreme hypericin concentrations (1 x 10(-9) M and 1 x 10(-6) M) resulted in similar changes in all tested cellular parameters on the two studied cell lines, 1 x 10(-8) M and 1 x 10(-7) M hypericin treatment resulted in different responses of the cell lines in all monitored parameters except for viability. Although leukemic cells proved sensitive to both 1 x 10(-8) M and 1 x 10(-7) M hypericin, significant changes on HT-29 cells were detected only after the 1 x 10(-7) M hypericin concentration. Cell-cycle arrest was related to simultaneously occurring apoptosis in colon cancer. Remarkable is the difference in cell-cycle profile where G2/M arrest in colon cancer cells versus accumulation of leukemic cells in the S phase appears. This suggests that hypericin treatment affecting the cell-cycle machinery of different cancer cells is not universal in effect.     

Chemical constituents of two sages with free radical scavenging activity

From the aerial parts of Salvia trichoclada Bentham and S. verticillata L. one new and two known phenolic acids, 3-(3',4'-dihydroxyphenyl)-2-hydroxymethyl propionic acid (1), 3-(3',4'-dihydroxyphenyl) lactic acid (2), and rosmarinic acid (3); two flavonoids, apigenin 4'-methyl ether 7-O-glucuronide (4), and luteolin 7-O-beta glucuronide (5); two lupan type triterpene aglycones, lupeol (6), and 30-hydroxylup-20 (29)-en-3-on (7); an oleanane-type triterpene acid, oleanolic acid (8); and an ursan-type triterpene acid, ursolic acid (9) were isolated. The structures of the compounds were elucidated by spectroscopic analysis. Different extracts of the plants were examined for their free radical scavenging activities by DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay. Some of the polar extracts showed high free radical scavenging activity.     

Cytotoxic triterpenes from Salvia buchananii roots

A pentacyclic triterpene, named salvibuchanic acid (1), together with five known compounds, were isolated from the roots of Salvia buchananii Hedge (Lamiaceae). The structural characterisation of all compounds was performed by spectroscopic analyses, including 1D and 2D NMR and HRESIMS experiments. The lupane triterpene (1) and hyptadienic acid (2) were investigated for their potential cytotoxic activity on Jurkat, HeLa and MCF7 cell lines. Both compounds showed an interesting antiproliferative activity with similar potency in all cell lines. By means of flow cytometric studies, hyptadienic acid (2) induced in HeLa cells a S cell cycle block, while 1 elicited both cytostatic and cytotoxic responses.     

Dicarba-closo-dodecaboranes as a pharmacophore. Retinoidal antagonists and potential agonists

Synthesis and biological evaluation of the first dicarba-closo-dodecaborane (carborane) derivatives of retinoids are described. Their retinoidal activity were examined in terms of the differentiation-inducing ability toward human promyelocytic leukemia HL-60 cells. High retinoidal activity (agonist or antagonist for retinoic acid receptor (RAR) requires a carboxylic acid moiety and an appropriate hydrophobic group located at a suitable position on the molecule. The 4-carboranyl-substituted compounds (7, 11) showed antagonistic activity but no agonistic activity even in the presence of the potent synergist HX630. On the other hand, the 3-carboranyl-substituted compounds (8, 12) showed potential agonistic activity, but no antagonistic activity. The results indicates that carboranes are applicable as the hydrophobic moiety of biologically active molecules.     

Antioxidant and cytotoxic properties of some new dipeptide-indole conjugates

In this study, 10 new indole-dipeptide conjugates were synthesized, and their anticancer activity was determined against on A2780 (ovarian cancer cell line) and MCF-7 (breast cancer cell line) cells. Among compounds, 5 and 10 showed better activity against A2780 cell lines than the standard drug docatexel at 0.1 and 1 μM concentrations, while only compound 5 showed better activity than docatexel, the MCF-7 cell line at 0.1 and 1 μM concentrations. The antioxidant potencies of the compounds were low in both the DPPH and iron reducing power methods tested when compared to standard antioxidants used in this work.     

Triterpene Saponins from <i>Pleurospermum kamtschaticum</i> and Their Biological Activity

Eleven new triterpene saponins (1-11), together with fourteen known triterpene and triterpene saponins (12-25) were isolated from a MeOH extract of Pleurospermum kamtschaticum HOFFMANN (Umbelliferae). The chemical structures of the new compounds (1-11) were determined by means of MS, ¹H-NMR, ¹³C-NMR, correlated spectroscopy (COSY), heteronuclear multiple bond correlation (HMBC), total correlated spectroscopy (TOCSY) and nuclear Overhauser effect spectroscopy (NOESY) to be pleurosaponin A (1)-K (11). The isolated compounds were tested for their cytotoxicity against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, HCT15) in vitro using the sulforhodamine B bioassay (SRB) assay. All compounds showed little cytotoxicity against tested cell lines (IC50 >30?μM).     

Synthetic studies of vitamin D analogues. IX. Synthesis and differentiation-inducing activity of 1 alpha,25-dihydroxy-23-oxa-, thia-, and azavitamin D3.

Three vitamin D3 analogues, 1 alpha,25-dihydroxy-23-oxavitamin D3 (3), 1 alpha,25-dihydroxy-23-thiavitamin D3 (4) and 1 alpha,25-dihydroxy-23-azavitamin D3 (5) were synthesized. In the differentiation-inducing activity of human myeloid leukemia cells into macrophages in vitro, the 23-aza analogue (5) showed the least activity, while no remarkable differences were observed between the 23-oxa analogue (3) and the 23-thia analogue (4), which were less active than 1 alpha,25-dihydroxyvitamin D3 (1).     

Design, Synthesis and Anticancer Activities of Diaryl Urea Derivatives Bearing <i>N</i>-Acylhydrazone Moiety

A new series of diaryl urea derivatives bearing N-acylhydrazone moiety were designed and synthesized. All the target compounds were evaluated for their cytotoxic activities in vitro against human lung adenocarcinoma epithelial cell line (A549), human breast cancer cell line (MDA-MB-231) and human leukemia cell line (HL-60) by standard 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Several compounds (1a, 1f and 1h) were further evaluated against human embryonic fibroblast, lung-derived cell line (WI38). The pharmacological results indicated that some compounds exhibited promising anticancer activities. In particular, compound 1f showed the most potent cytotoxicity against the tested three cell lines with IC50 values of 0.41?μM, 0.24?μM and 0.23?μM, respectively.     

Antioxidant-prooxidant properties of a new organoselenium compound library

The present study describes the biological evaluation of a library of 59 organo-selenium compounds as superoxide (O??) generators and cytotoxic agents in human prostate cancer cells (PC-3) and in breast adenocarcinoma (MCF-7). In order to corroborate that the biological activity for selenium compounds depends on the chemical form, a broad structural variety is presented. These structures include selenocyanates, diselenides, selenoalkyl functional moieties and eight newly synthesized symmetrically substituted dithioselenites and selenylureas. Eleven of the derivatives tested showed high levels of superoxide generation in vitro via oxidation of reduced glutathione (GSH) and nine of them were more catalytic than the reference compound, diselenodipropionic acid. Eighteen of the library compounds inhibited cell growth more than or similar to reference chemotherapeutic drugs in PC-3 and eleven were more potent cytotoxic agents than etoposide in the MCF-7 cell line. Considering both parameters (superoxide generation and cell cytotoxicity) compounds B1, C6 and C9 displayed the best therapeutic profiles. Considering that many diselenide compounds can generate superoxide (O??) in vitro via oxidation of GSH and other thiols, the analogue B1, that contains a diselenide moiety, was selected for a preliminary mechanistic investigation, which revealed that B1 has apoptogenic effects similar to camptothecin mediated by reactive oxygen species (ROS) in lymphocytic leukemia cells (CCRF-CEM) and affected the MCF-7 cell-cycle in G?/M and S-phases.     

Chemical investigation of Finlaysonia obovata: part I--a rare triterpene acid showing antibacterial activity against fish pathogens

The antibacterial screening of extracts of the leaves of Finlaysonia obovata with hexane, chloroform and alcohol was carried out against fresh water fish pathogenic bacteria viz., Micrococcus Sp. (multidrug resistant strain), Aeromonas hydrophila, Pseudomonas aeruginosa, Vibrio alginolyticus, Staphylococcus aureus, Escherichia Coli, Edwardsiella tarda by disc-assay method. The hexane and chloroform extracts were found active against four and five pathogens, respectively. The highly active chloroform extract was taken up for fractionations, further screening and isolation of secondary metabolites by chromatographic techniques. The triterpene acid Urs-3beta-hydroxy-12-en-27-oic acid (3), which is very rarely found from plant sources is isolated first time from this plant along with known compounds; Lupeol acetate (1) and beta-Sitosterol (2). This article presents for the first time all the spectral data for Urs-3beta-hydroxy-12-en-27-oic acid (3), which showed moderate activity against four pathogens. This is the first report of antibacterial activity of a triterpene against fish pathogens.     

Methyl Jasmonate Effect on Betulinic Acid Content and Biological Properties of Extract from Senna obtusifolia Transgenic Hairy Roots

It is known that Senna obtusifolia has been used in medicine since ancient times due to the content of many valuable compounds with a pro-health effect. One of them is betulinic acid, which is a pentacyclic triterpene with antimalarial, antiviral, anti-inflammatory and anticancer properties. In this work, a continuation of our previous research, an attempt was made to increase the level of betulinic acid accumulation by the cultivation of transgenic hairy roots that overexpress the squalene synthase gene in a 10 L sprinkle bioreactor with methyl jasmonate elicitation. We present that the applied strategy allowed us to increase the content of betulinic acid in hairy root cultures to the level of 48 mg/g dry weight. The obtained plant extracts showed a stronger cytotoxic effect on the U87MG glioblastoma cell line than the roots grown without elicitors. Additionally, the induction of apoptosis, reduction of mitochondrial membrane potential, chromosomal DNA fragmentation and activation of caspase cascades are demonstrated. Moreover, the tested extract showed inhibition of topoisomerase I activity.     

Anti-tumour activities and a high-performance liquid chromatography mass spectrometric method for analysis of the constituents of Lomatogonium carinthiacum

In the present study, extracts of CHCl(3), n-BuOH and water of Lomatogonium carinthiacum were tested for their possible anticancer effects on human lung adenocarcinoma A549 cell line, human erythroleukaemia K562 cell line and human cervical carcinoma HeLa cell line. The inhibitory effect of the extracts on cell proliferation was assessed by MTT colourimetric assay in vitro. A high-performance liquid chromatography-electrospray-mass spectrometric (HPLC-EIS-MS/MS) method was developed for the determination of the constituents of the extracts. According to HPLC-EIS-MS/MS data, the chemical structures of 21 constituents of L. carinthiacum were identified on-line without time-consuming isolation. The L. carinthiacum extracts showed inhibitory effects on the abovementioned cell lines. Extracts of CHCl(3) were found to be the most inhibitory, with IC(50) values of 0.13, 0.75 and 0.60 μg mL(-1) on A549, K562 and HeLa, respectively. According to the IC(50) values, the order of sensitivity of the cell lines was A549 > HeLa > K562 and the inhibitory effects to the cell lines of these extracts were in the order CHCl(3) extract > water extract > n-BuOH, as xanthones > iridoids and secoiridoids > flavonols. The present study showed inhibitory activity of L. carinthiacum extracts on tumour cells.     

Clerodendrumol,A New Triterpenoid from Clerodendrum yaundense Gürke (Lamiaceae)

A new lupane‐type triterpene named clerodendrumol ( 1 ), i.e., (16α)‐lupa‐12,20(29)‐dien‐16‐ol, together with five known compounds, octacosa‐(5Z,9Z)‐dienoic acid ( 3 ), tetracosanoic acid ( 4 ), genkwanin ( 5 ), (12S)‐hydroxyoctadeca‐(9Z,13E,15E)‐trienoic acid ( 6 ), and (9S)‐hydroxyoctadeca‐(10E,12E)‐dienoic acid ( 7 ), were isolated from the twigs of Clerodendrum yaundense. O‐Acetylclerodendrumol ( 2 ), a derivative of 1 , was prepared by a standard acetylation procedure applied to compound 1 . The structure of the new compound was elucidated using spectroscopic analysis (NMR and MS) data, and chemical conversions (acetylation and deacetylation). The human breast cancer cell line (MDA‐MB‐231) was sensitive to all test samples, and clerodendrumol ( 1 ) as well as its derivative 2 had good activity (IC₅₀ values 7.5 and 13.2 μM ). Genkwanin ( 5 ) exhibited strong activity on HeLa cell line with IC₅₀ 7.8 μM .