Autophagy machinery plays an essential role in traumatic brain injury-induced apoptosis and its related behavioral abnormalities in mice: focus on Boswellia Sacra gum resin

Traumatic brain injury (TBI) is described as a structural damage or physiological disturbance of brain function that occurs after trauma and causes disability or death in people of all ages. New treatment targets for TBI are being explored because current medicines are frequently ineffectual and poorly tolerated. There is increasing evidence that following TBI, there are widespread changes in autophagy-related proteins in both experimental and clinical settings. The current study investigated if Boswellia Sacra Gum Resin (BSR) treatment (500 mg/kg) could modulate post-TBI neuronal autophagy and protein expression, as well as whether BSR could markedly improve functional recovery in a mouse model of TBI. Taken together our results shows for the first time that BSR limits histological alteration, lipid peroxidation, antioxidant, cytokines release and autophagic flux alteration induced by TBI.

Molecular Modes of Action of an Aqueous Nerium oleander Extract in Cancer Cells In Vitro and In Vivo

Cancer drug resistance remains a major obstacle in clinical oncology. As most anticancer drugs are of natural origin, we investigated the anticancer potential of a standardized cold-water leaf extract from Nerium oleander L., termed Breastin. The phytochemical characterization by nuclear magnetic resonance spectroscopy (NMR) and low- and high-resolution mass spectrometry revealed several monoglycosidic cardenolides as major constituents (adynerin, neritaloside, odoroside A, odoroside H, oleandrin, and vanderoside). Breastin inhibited the growth of 14 cell lines from hematopoietic tumors and 5 of 6 carcinomas. Remarkably, the cellular responsiveness of odoroside H and neritaloside was not correlated with all other classical drug resistance mechanisms, i.e., ATP-binding cassette transporters (ABCB1, ABCB5, ABCC1, ABCG2), oncogenes (EGFR, RAS), tumor suppressors (TP53, WT1), and others (GSTP1, HSP90, proliferation rate), in 59 tumor cell lines of the National Cancer Institute (NCI, USA), indicating that Breastin may indeed bypass drug resistance. COMPARE analyses with 153 anticancer agents in 74 tumor cell lines of the Oncotest panel revealed frequent correlations of Breastin with mitosis-inhibiting drugs. Using tubulin-GFP-transfected U2OS cells and confocal microscopy, it was found that the microtubule-disturbing effect of Breastin was comparable to that of the tubulin-depolymerizing drug paclitaxel. This result was verified by a tubulin polymerization assay in vitro and molecular docking in silico. Proteome profiling of 3171 proteins in the NCI panel revealed protein subsets whose expression significantly correlated with cellular responsiveness to odoroside H and neritaloside, indicating that protein expression profiles can be identified to predict the sensitivity or resistance of tumor cells to Breastin constituents. Breastin moderately inhibited breast cancer xenograft tumors in vivo. Remarkably, in contrast to what was observed with paclitaxel monotherapy, the combination of paclitaxel and Breastin prevented tumor relapse, indicating Breastin's potential for drug combination regimens.

Comparative Investigation of Frankincense Nutraceuticals: Correlation of Boswellic and Lupeolic Acid Contents with Cytokine Release Inhibition and Toxicity against Triple-Negative Breast Cancer Cells

For centuries, frankincense extracts have been commonly used in traditional medicine, and more recently, in complementary medicine. Therefore, frankincense constituents such as boswellic and lupeolic acids are of considerable therapeutic interest. Sixteen frankincense nutraceuticals were characterized by high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS), revealing major differences in boswellic and lupeolic acid compositions and total contents, which varied from 0.4% to 35.7%. Frankincense nutraceuticals significantly inhibited the release of proinflammatory cytokines, such as TNF-α, IL-6, and IL-8, by LPS-stimulated peripheral blood mononuclear cells (PBMC) and whole blood. Moreover, boswellic and lupeolic acid contents correlated with TNF-α, IL-1β, IL-6, IL-8, and IL-10 inhibition. The nutraceuticals also exhibited toxicity against the human triple-negative breast cancer cell lines MDA-MB-231, MDA-MB-453, and CAL-51 in vitro. Nutraceuticals with total contents of boswellic and lupeolic acids >30% were the most active ones against MDA-MB-231 with a half maximal inhibitory concentration (IC₅₀) ≤ 7.0 µg/mL. Moreover, a frankincense nutraceutical inhibited tumor growth and induced apoptosis in vivo in breast cancer xenografts grown on the chick chorioallantoic membrane (CAM). Among eight different boswellic and lupeolic acids tested, β-ABA exhibited the highest cytotoxicity against MDA-MB-231 with an IC₅₀ = 5.9 µM, inhibited growth of cancer xenografts in vivo, and released proinflammatory cytokines. Its content in nutraceuticals correlated strongly with TNF-, IL-6, and IL-8 release inhibition.

Abstract 5572: Breastin a natural product from Nerium Oleander exhibits high activity in a panel of human tumor cell lines

Background: More than half of all registered anticancer agents were originally derived from natural sources. We isolated and screened >2.000 pure compounds, and purified extracts from microorganisms and plants in a panel of human tumor cell lines (Kelter et al. ENA 2008). Here we report on the activity of Breastin, a defined extract isolated from the plant Nerium Oleander in 63 human cell lines. The mode of action was elucidated by comparing the activity profile with that of known anticancer agents with defined mechanism.

Methods: Breastin was isolated as cold extract from the leaves of the plant Nerium Oleander. It contains defined amounts of glycosides, flavonoides and polysaccharides. In-vitro activity was determined in 63 human tumor cell lines in a monolayer assay. 4 to 10,000 cells were seeded in 96 well plates; one day later Breastin was added at 5 concentrations and incubated with the cells for 4 days. The read-out was propidium iodide-based fluorescence. Based on IC50 and IC70 values tumor selectivity was analyzed. In the Compare Analysis the IC50 and IC70 pattern of Breastin was compared with the corresponding patterns of 180 known substances using Spearman Correlations.

Results: Breastin showed a dose-dependent antitumor activity, the mean IC50 and IC70 were 1.1 and 2.7 μg/ml, respectively. It was the most potent and selective preparation out of a series of 36 extracts that were obtained with different extraction procedures. 31 / 63 cell lines investigated showed IC50 < 1.14 μg/ml. Breastin had a higher potency than several anticancer agents used in the clinic, e.g. Cisplatin, 5-Fluoruracil and Cyclophosphamide. The highest activity was seen in bladder, CNS, colon and NSC lung cancer cell lines as well as in pancreas and prostate models. In systematic combination studies Breastin increased the effect of the tubuline binders Paclitaxel, and Docetaxel in 4/6 cell lines, the alkylating agents Cyclophamide and Mitomycin, adriamycin and alimta.

The Compare Analyses showed no similarity with 180 known anticancer agents, the coefficients of correlation were < 0.6 in all cases. Therefore Breastin has probably a different mechanism of action. In previous studies components of Breastin acted as specific inhibitors of the membrane Na+/K+ ATPase. This type of compounds is not included in the reference data base. Analyses of predictive biomarkers and gene patterns are ongoing.

In former studies in-vivo activity was determined in murine models: B16 melanoma and Lewis-Lung-carcinoma were sensitive, leukemias L1210 and P388 were resistant.

Conclusion: The evaluation of 36 extracts from Nerium Oleander identified the cold extract called Breastin as most promising anticancer agent with selective in-vitro activity found in bladder, CNS, colon and NSC lung cancer cell lines as well as in pancreas and prostate models. Moreover, in combination studies Breastin showed synergism with severall cytotoxic drugs.

Citation Format: Heinz H. Fiebig, Gerhard Kelter, Armin Maier, Thomas Metz, Luay J. Rashan. Breastin a natural product from Nerium Oleander exhibits high activity in a panel of human tumor cell lines. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5572. doi:10.1158/1538-7445.AM2013-5572

Characterization of the anticancer properties of monoglycosidic cardenolides isolated from Nerium oleander and Streptocaulon tomentosum

AIM OF THE STUDY

For identification of the active constituents we investigated the anticancer activity of cardenolides from Streptocaulon tomentosum Wight & Arn. (Asclepiadaceae) and from Nerium oleander L. (Apocynaceae) which are both used against cancer in the traditional medicine in their region of origin.

MATERIAL, METHODS AND RESULTS

The antiproliferative activity of cardenolides isolated from roots of Streptocaulon tomentosum (IC(50)<1-15.3 μM after 2 days in MCF7) and of cardenolide containing fractions from the cold aqueous extract of Nerium oleander leaves ("Breastin", mean IC(50) 0.85 μg/ml in a panel of 36 human tumor cell lines), their influence on the cellular viability and on the cell cycle (block at the G2/M-phase or at the S-phase in tumor cells, respectively) were determined using different cell lines. The murine cell line L929 and normal non-tumor cells were not affected. Bioactivity guided fractionation of Breastin resulted in the isolation of the monoglycosidic cardenolides oleandrine, oleandrigeninsarmentoside, neritaloside, odoroside H, and odoroside A (IC(50)-values between 0.010 and 0.071 μg/ml).

CONCLUSIONS

The observed anticancer activities of extracts and isolated cardenolides are in agreement with the ethnomedicinal use of Streptocaulon tomentosum and Nerium oleander. The most active anticancer compounds from both species are monoglycosidic cardenolides possessing the 3β,14β-dihydroxy-5β-card-20(22)-enolide structure with or without an acetoxy group at C-16. The results indicate that the cytotoxic effects are induced by the inhibition of the plasma membrane bound Na(+)/K(+)-ATPase.

Synthesis, crystal structure and initial biological evaluation of the new enantiomerically pure chiral palladium(II) complex trans-bis[endo-(1R)-1,7,7-trimethylbicyclo[2.2.1]-heptan-2-amino]palladium(II)dichloride

The palladium(II) complex trans-bis[(R)-(+)-bornylamino]palladium(II) dichloride was synthesised and characterised. The solid state structure of the complex was determined by X-ray structure analysis. The compound crystallises in the monoclinic space group P2(1) with a=12.383(2), b=23.689(5), c=12.769(3) A, beta=93.25(3) degrees, and V=3739.6(13) A(3). The complex was tested for its cytotoxicity against L(929), K(562) and HeLa cell lines using the MTT assay technique. It is also tested for its anticomplementary activity using a test that detects complement proteins inhibition. These activities were compared with those of the reference standards, cisplatin, carboplatin and oxaliplatin. The significance of these results is given and discussed.

Cis- and trans-platinum and palladium complexes: a comparative study review as antitumour agents

A large body of novel platinum and palladium complexes, in both the cis- and trans-forms, with various donor ligands, e.g. beta-carboline alkaloids, pyrazoles, DMSO, ferrocenylphosphines,...... have been tested for their antitumour activity against number of fluid suspension (P388, L1210, K562, and Raji) and solid tumour (KB, T47D, SW948, HeLa, A549, L929, Hep-2, RD,...) cell lines. Remarkable cytotoxic effects against these cell lines were observed by some of these complexes. The preliminary results indicated that most of the trans-palladium complexes showed a better activity than the cis-platinum isomers and superior activity than that of the cis-palladium isomers. More importantly they showed activities equal to (or superior than) those of cisplatin, carboplatin and oxaliplatin (the anti-cancer drugs) in vitro. Although these results are preliminary, however, encouraging since they are in a disagreement with the previous studies that cis-isomers are more active than trans-ones; the complexes which have not received the required attention from the vast number of researchers in this field.

Cytotoxic activity against a series of tumour cell lines of dimethyltin dichloride complexes with various donor ligands

Several dimethyltin dichloride complexes of the general formula Me2SnCl2.L, where L = 8-hydroxy quinoline (L1), 8-hydroxy quinoline-N-oxide (L2),2,6-diaminopyridine (L3), 3-amino aniline (L4), cyclohexyl amine (L5), (1R, 2R)-1,2-cyclohexane diamine (L6), 3,5-dimethylpyrazole (L7), harmaline (L8) and harmine (L9), have been prepared and characterized physicochemically and spectroscopically. It was found that tin coordinated with the active site of these ligands to give complexes with penta-coordinated tin or, to some extent, hexa-coordinated tin. The cytotoxic activities of these complexes have been studied against Hep-2, HeLa, L20B and RD lines using the MTT-colorimetric assay. These activities were compared with those of the three reference standards, cisplatin, carboplatin and oxaliplatin. Some of these complexes exhibited a range of significant activities against the cell lines used, whereas no cytotoxic activities were exhibited by the rest of these complexes. The significance of these results is given and discussed.

Dimethyltin(IV) carboxylate compounds; synthesis, characterization and in vitro cytotoxic activity

Six dimethyltin(IV) carboxylate compounds of the general formula Me2SnX2, where X = 1/2 O2(CO)2 (oxalate), 1/2 O2(CO)2CH2 (malonate), 1/2 O2(CO)2CH = CH (maleate), 1/2 O2(CO)2C-CH2CH2CH2 (cyclobutyl dicarboxylate), O(CO)C6H11 (cyclohexane carboxylate) and O(CO)CMe3 (pivolate) have been prepared and characterized physicochemically and spectroscopically. The cytotoxic activities of these carboxylates have been studied against HeLa, Hep-2, RD, L20B and P388 cell lines using the MTT-colorimetric assay. These activities were compared with the cytotoxic activities of the three reference standards, cisplatin, carboplatin and oxaliplatin. The compounds were X = 1/2 malonate, 1/2 maleate, cyclohexane carboxylate and pivolate exhibited a range of significant activities against the cell lines used, whereas no cytotoxic activities were exhibited by the rest of the six compounds. The significance of these results is given and discussed.

Cytotoxic activity of diorganotin(IV) complexes of some xanthate derivatives

The cytotoxic activities of diorganotin(IV) complexes of some xanthate derivatives; R2Sn(SSCOR'), where R = Me, Bu(n), Ph and R' = C6H11 - (CyX), CH3NHCHCH2 - (MAEX), (CH3)2NCH2CH2 - (DMAEX), (CH3)2NCH2CH(CH3) - (DMAIX) and (C2H5)2NCH2CH2 - (DEAEX), have been studied against Hep-2, Hela, RD, L20B and BGM cell lines using the MTT-colorimetric assay. The present results indicated that moderate activities were demonstrated by the xanthate complexes of Bu(n)2Sn(IV) against four cell lines, whereas no cytotoxic activities were exhibited by both Me2Sn(IV) and Ph2Sn(IV) complexes of the xanthates. These activities were compared with the cytotoxic activities of two reference standards; the cisplatin and paraplatin complexes. The significance of these results is discussed.

Antibacterial evaluation of some xanthate derivatives and their diorganotin (IV) complexes

The antibacterial activity of some xanthate derivatives K(SSCOR), where R = C6H5-(CyX), CH3NHCH2CH2-(MAEX), (CH3)2NCH2CH2-(DMAX), (CH3)2NCH2CH(CH3)-(DMAIX) and (C2H5)2NCH2CH2-(DEAEX) together with their diorganotin (IV) complexes R2Sn(SSCOR)2, where R' = Me, Bu(n), Ph, has been studied against eight species of bacteria in vitro. A significant activity against S. typhimurium was displayed by the xanthate derivative CyX and its complex Ph2Sn(CyX)2 at concentrations ranging from 1-10 micrograms/ml, and a remarkable activity was exhibited by the complexes Ph2Sn(CyX)2, Ph2Sn(MAEX)2 and Ph2Sn(DMAX)2 against P. aeruginosa at concentrations ranging from 0.1-10 micrograms/ml. By contrast, no such activity was demonstrated by the antibiotics used in this study (amoxicillin and chloramphenicol) against the same bacterial species.

Antibacterial and antiproliferative activities of vulpinic acids in vitro

The antimicrobial and antiproliferative activities of vulpinic acids (1 a, b, c) have been assayed in vitro. Activity was demonstrated by vulpinic acids on Gram-positive bacteria only. The MIC values of these compounds were found to be ranging from 3.8-31.5 micrograms/ml. The significance of these results is discussed.

Synthesis and biological evaluation of N-salicyloyl-N-benzyl thiourea and 2,2-dimethyl-4-oxo-6-methoxy benzo-1,3-dioxin

The synthesis of N-salicyloyl-N-benzyl-thiourea and 2,2-dimethyl-4-oxo-6-methoxy-benzo-1,3-dioxin are described. They were studied for their antiviral, antiproliferative and antimicrobial activities in vitro. N-salicyloyl-N-benzyl-thiourea exhibited significant activity against Gram-positive bacteria and against influenza viruses types A/Philippine/H3N2, A/Chilli/H1N1 and B/Paraha, as well as against K562 cell proliferation. By contrast, no such activity was demonstrated by 2,2-dimethyl-4-oxo-6-methoxy-benzo-1,3-dioxin.

Synthesis and characterization of novel biologically active platinum(II) and palladium(II) complexes of some beta-carboline alkaloids

The preparation of novel biologically active platinum(II) and palladium(II) complexes of some beta-carboline alkaloids (harmaline, harmalol, harmine, and harmane) is described. These complexes, characterized on the basis of their CHN elemental analysis, infrared, Raman and 1H and 13C nuclear resonance spectral data, were shown to have the empirical formula [M(alkaloid)Cl2], M = Pt, Pd. The antitumor and antiviral activities of some of these complexes have been demonstrated.

Synthesis and antiviral evaluation of 6-p-ethylphenyl-5H-pyrrolo [3,4-b]pyridine-5,7-dione

The synthesis of 6-(p-ethylphenyl)-5H-pyrrolo [3,4-b]pyridine-5,7-dione is described. The compound has been studied for its in vitro activity on RNA-containing influenza viruses types A and B. The preliminary results indicate that the compound has a significant antiviral activity against influenza viruses types A and B at concentrations at which no cytotoxic effects on MRC-5 cells in tissue culture are present.