Koenimbine

Assessment of anti-cancer effects of koenimbine on colon cancer cells.[Pubmed:32116245]

Hum Antibodies. 2020 Feb 14. pii: HAB200405.

BACKGROUND: Recent studies have highlighted the role of natural elements in reduction of cancer cell growth and apoptosis. Koenimbine, a natural product isolated from Murraya koenigii (L) Spreng is a substance with cytotoxic effects on cancer cells. AIM: The effects of Koenimbine on HT-29 and SW48 colon cancer cells were evaluated by MTT and Annexin V assays. Expression levels of Wnt/beta-catenin pathway genes were quantified by real time PCR. RESULTS: The IC50 values of Koenimbine in HT-29 and SW48 was calculated to be 50 mug/ml based on the results of MTT assay. This value was 75 mug/ml in IEC-18 cells which were used as normal control. Annexin V assays revealed induction of cell apoptosis and necrosis in HT-29 and SW48 cells but not IEG18 cells by Koenimbine. Koenimbin treatment resulted in significant down-regulation of CYCLD1 expression in SW48 cell line, but up-regulation of this gene in HT29 cell line. Expression of TBLR1, DKK1, GSK3B and beta-catenin was significantly decreased after koenimbin treatment in HT-19 cell line. Moreover, expression of DKK1 and GSK3B was significantly decreased after koenimbin treatment in SW-40 cell line. TCF4 expression was not detected in any of cell lines either before or after treatment with koenimbin. CONCLUSION: The current in vitro study showed the cytotoxic effects of koenimbin on two colon cancer cell lines and the effects of this substance on expression of selected genes from Wnt-beta catenin pathway. Future in vivo studies are needed before suggestion of this substance as an anti-cancer drug.

Influence of Geographical and Seasonal Variations on Carbazole Alkaloids Distribution in Murraya koenigii: Deciding Factor of Its In Vitro and In Vivo Efficacies against Cancer Cells.[Pubmed:32104704]

Biomed Res Int. 2020 Feb 11;2020:7821913.

Murraya koenigii is a well-known Indian medicinal herb, and a carbazole alkaloid (mahanine) from this plant causes apoptosis in cancer cells. Here, we investigated how seasonal and geographical variations influence carbazole alkaloids composition and medicinal property of this plant against cancer cells in vitro and in vivo. Leaflets were collected from various places in different seasons for three years. A mahanine-enriched fraction (MEF) was prepared in two steps using ethanol and water. The best plant was selected based on the highest percent of mahanine. MEF prepared from leaflets of nine different locations showed a different concentration of identified markers (mahanine, mahanimbine, and Koenimbine) which exhibited differential reduced metabolic activity against ovarian cancer, mahanine being the best. Our systematic study revealed that mahanine content was highest during September-December. Interestingly, MEF from southern part (tropical zone) exhibited 43 +/- 2.5% mahanine compared to 2.7 +/- 1.3% in northeastern part (subtropical zone) with five folds higher activity against PA1. Moreover, MEF reduced metabolic activity of sixteen cancer cell lines from nine different origins and significantly reduced tumor mass in lung and ovarian cancer xenograft models. Taken together, this is the first report demonstrating the marker's content in these leaflets is highly dependent on location/season. A positive correlation between biological activity and mahanine concentration was established in MEF. Such a comprehensive study suggests that the selection of location and suitable season for collection of any plant materials with biologically active stable markers in sufficient quantity play a decisive role in determining the fate of their medicinal property.

Pyranocarbazole derivatives as potent anti-cancer agents triggering tubulin polymerization stabilization induced activation of caspase-dependent apoptosis and downregulation of Akt/mTOR in breast cancer cells.[Pubmed:30772606]

Eur J Med Chem. 2019 Apr 1;167:226-244.

A series of new pyranocarbazole derivatives were synthesized via semi-synthetic modification of Koenimbine (1a) and koenidine (1b) isolated from the leaves of Murraya koenigii. Among all, compound 3bg displayed significant anti-cancer activity against MDA-MB-231, DU145 and PC3 cell lines with the IC50 values of 3.8, 7.6 and 5.8muM, respectively. It was also observed that the halogenated-benzyl substitution at N-9 position, C-3 Methyl and C-7 methoxy group on carbazole motif are favoured for anti-cancer activity. The detailed investigation was carried out with compound 3bg and its SEDDS (self-emulsifying drug delivery systems) formulation 3bgF. The in vivo drug release behavior study showed that the formulation enhanced slow release and better bioavailability at a tumor site. Compound 3bg and its formulation (3bgF) significantly inhibited cell proliferation and colony formation, induced G2/M arrest, reduced cellular ROS generation and induced caspase-dependent apoptosis in MDA-MB-231cells. 3bg also induced significant alteration of Bax/Bcl expression ratio suggesting involvement of mitochondrial apoptosis. Additionally, 3bg caused down-regulation of mTOR/Akt survival pathway. 3bg do not bind to DNA, but interacts with tubulin as observed with in silico molecular docking studies. This interaction results in stabilization of tubulin polymerization similar to paclitaxel as detected in cell-free assay. Oral administration of 3bgF for 30 days at dose rate of 10 and 20mg/kg body weight significantly reduced tumor growth in syngenic rat LA-7 mammary tumor model. These results indicated that the pyranocarbazole natural product based N-substituted analogues can act as potential anti-cancer lead.

The Role of Oxidative Stress in Koenimbine-Induced DNA Damage and Heat Shock Protein Modulation in HepG2 Cells.[Pubmed:27879375]

Integr Cancer Ther. 2017 Dec;16(4):563-571.

BACKGROUND: Murraya koenigii (L.) Spreng, is a significant herb of traditional Ayurvedic system of medicine. Koenimbine, a carbazole alkaloid isolated from this plant holds antiproliferative and apoptotic effects. The aim of this study was to assess Koenimbine-induced DNA damage and to clarify the role of free radicals in cell death mechanisms, using HepG2 cells. METHODS: The level of cytotoxicity was assayed by MTT assay. To elucidate the role of glutathione (GSH), the intracellular GSH level was analyzed. The effect of Koenimbine in the cell mitochondria was evaluated using mitochondrial membrane potential (MMP) changes. Single cell gel electrophoresis assay was used to examine the level of DNA damage. Heat shock proteins, Hsp 70 and Hsp 90 expressions were checked at mRNA and protein level. Ascorbic acid and catalase were used as control antioxidants. RESULTS: It was observed that Koenimbine considerably increased DNA damage in HepG2 cells at subcytotoxic concentrations. Koenimbine induced the increased levels of reactive oxygen species (ROS) and reduction of GSH level in HepG2 cells, together with time-dependent loss of MMP. In addition, results clearly showed that Koenimbine encouraged cells to express Hsp 70 and Hsp 90 in a concentration-dependent manner up to a concentration of 100 microM and a time-dependent manner at 24-hour incubation both at transcriptional and translational levels. The antioxidant capacity of ascorbic acid was found to be not as prominent as to catalase throughout the study. CONCLUSION: Based on these data it can be concluded that Koenimbine causes DNA strand breaks in HepG2 cells, probably through oxidative stress. Moreover, the oxidative stress induced was closely associated with MMP reduction and GSH depletion associated with HSP modulation at subcytotoxic concentration.

Four new carbazole alkaloids from Murraya koenigii that display anti-inflammatory and anti-microbial activities.[Pubmed:26947457]

Org Biomol Chem. 2016 Mar 28;14(12):3322-32.

In our present study, four new, designated as murrayakonine A-D (), along with 18 known carbazole alkaloids were isolated from CHCl3 : MeOH (1 : 1) crude extracts of the stems and leaves of Murraya koenigii (Linn.) Spreng. The structures of the all isolated compounds were characterized by analysis of HR-ESI-MS and NMR (1D and 2D spectroscopy) results, and comparison of their data with the literature data. For the first time, all the isolates were evaluated for their anti-inflammatory activities, using both in vitro and in vivo experiments, against the key inflammatory mediators TNF-alpha and IL-6. The new compound murrayakonine A (), O-methylmurrayamine A () and murrayanine () were proven to be the most active, efficiently inhibiting TNF-alpha and IL-6 release in a dose-dependent manner and showing decreased LPS induced TNF-alpha and IL-6 production in human PBMCs [corrected]. Furthermore, all the isolates were screened for their antimicrobial potential, and the compounds girinimbine () (IC50 3.4 muM) and 1-hydroxy-7-methoxy-8-(3-methylbut-2-en-1-yl)-9H-carbazole-3-carbaldehyde () (IC50 10.9 muM) displayed potent inhibitory effects against Bacillus cereus. Furthermore, compounds murrayamine J () (IC50 11.7 muM) and Koenimbine () (IC50 17.0 muM) were active against Staphylococcus aureus. However, none of the compounds were found to be active against Escherichia coli or Candida albicans.

Quantitative analysis of bioactive carbazole alkaloids in Murraya koenigii.[Pubmed:25920265]

Nat Prod Commun. 2015 Feb;10(2):293-5.

Carbazole alkaloids induce apoptosis in HL-60 cells through activation of the caspase-9/caspase-3 pathway and they are targeted as potential anticancer agents. Thus, the naturally occurring carbazole alkaloids become important as precursors for lead optimization in drug development. A method based on ultra performance liquid chromatography coupled with photodiode-array detection was developed using reverse phase isocratic elution with 85:15 acetonitrile and ammonium acetate buffer (5 mM). Seven samples of Murrya koenigii (L.) Spreng. from north-central India (Uttar Pradesh) were analyzed. All three targeted analytes, koenimbidine (mk1), Koenimbine (mk2) and mahanimbine (mk3), were well separated within 4.0 min with linearity of the calibration curves (r2 > 0.999). The limits of detection and quantification of mk1, mk2 and mk3 were 0.7, 0.4, 0.04 mug/mL and 2.14, 1.21, 0.12 mug/mL, respectively. The natural abundance of mk1, mk2 and mk3 was 0.06-0.20, 0.04-0.69 and 0.13-0.42%, w/w, respectively, in the dried powdered leaves, whereas, the tissue specific distribution of carbazole alkaloids was observed in the order of predominance, mk1 leaf>root>fruit>stem, mk2 fruit>leaf >stem>root, and mk3 fruit>leaf>root>stem. The developed method was validated for limits of detection and quantification, repeatability, accuracy, precision and stability. This is the first report on the natural abundance of the major carbazole alkaloids in M. koenigii and the method developed can be used in HPLC/UPLC systems.

A new carbazole alkaloid from the leaves of Malayan Murraya koenigii.[Pubmed:21972815]

J Asian Nat Prod Res. 2011 Oct;13(10):972-5.

New carbazole alkaloid, 7-hydroxymurrayazolinine (1), was isolated from the ethanol extract of the leaves of Malayan Murraya koenigii, together with five known carbazole alkaloids, mahanimbine (2), bicyclomahanimbine (3), girinimbine (4), Koenimbine (5), and murrayamine-D (6). Their structures were elucidated on the basis of spectroscopic analysis.

8-Meth-oxy-3,3,5-trimethyl-3,11-dihydro-pyrano[3,2-a]carbazole.[Pubmed:21587821]

Acta Crystallogr Sect E Struct Rep Online. 2010 Jun 5;66(Pt 7):o1581.

In the title compound, C(19)H(19)NO(2), commonly called Koenimbine, the pyran ring adopts a sofa conformation. The carbazole ring system is planar [r.m.s. deviation = 0.063 (1) A]. A C(10) zigzag chain running along the b axis is formed through inter-molecular C-Hcdots, three dots, centeredO hydrogen bonds. The chains are linked via weak C-Hcdots, three dots, centeredpi and N-Hcdots, three dots, centeredpi inter-actions.

Antidiarrhoeal activity of carbazole alkaloids from Murraya koenigii Spreng (Rutaceae) seeds.[Pubmed:19695314]

Fitoterapia. 2010 Jan;81(1):72-4.

The bioassay guided fractionation of the n-hexane extract of the seeds of Murraya koenigii Spreng (Rutaceae) resulted in the isolation of three bioactive carbazole alkaloids, kurryam (I), Koenimbine (II) and koenine (III). The structures of the compounds were confirmed from their (1)H-, (13)C-, and 2D-NMR spectral data. Of the three compounds (I) and (II) exhibited significant inhibitory activity against castor oil-induced diarrhoea and PGE(2)-induced enteropooling in rats. The compounds also produced a significant reduction in gastrointestinal motility in the charcoal meal test in Wistar rats.

Murrayakoeninol--a new carbazole alkaloid from Murraya koenigii (Linn) Spreng.[Pubmed:19413112]

Nat Prod Commun. 2009 Mar;4(3):355-8.

A new carbazole alkaloid, designated as murrayakoeninol, was isolated from the leaves of Murraya koenigii (Linn) Spreng, along with four known carbazole alkaloids, viz. mahanimbine, Koenimbine, O-methylmurrayamine-A and murrayazolinine and one from the bark viz. girinimbine. The structure of the new alkaloid 1 was elucidated on the basis of 2D NMR spectral analysis and chemical reactions.

Comparison of antioxidative properties of carbazole alkaloids from Murraya koenigii leaves.[Pubmed:14558763]

J Agric Food Chem. 2003 Oct 22;51(22):6461-7.

A new dimeric carbazole alkaloid, 8,10'-[3,3',11,11'-tetrahydro-9,9'-dihydroxy-3,3',5,8'-tetramethyl-3,3'-bis(4-met hyl-3-pentenyl)]bipyrano[3,2-a]carbazole (12), was isolated from the CH(2)Cl(2) extract of Murraya koenigii together with six known carbazole alkaloids, Koenimbine (6), O-methylmurrayamine A (7), O-methylmahanine (8), isomahanine (9), bismahanine (10), and bispyrayafoline (11). Their structures were determined on the basis of (1)H and (13)C NMR spectroscopic and mass spectrometric (MS) data. The antioxidative properties of 12 carbazole alkaloids isolated from leaves of M. koenigii were evaluated on the basis of the oil stability index together with their radical scavenging ability against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. On the basis of the lag time to reach a steady state, the 12 carbazoles were classified into three groups. It is suggested that an aryl hydroxyl substituent on the carbazole rings plays a role in stabilizing the thermal oxidation and rate of reaction against DPPH radical.