Thứ Bảy, 17 tháng 8, 2013

Cytotoxic Components of Pereskia bleo (Kunth) DC. (Cactaceae) Leaves



Molecules 2009, 14, 1713-1724; doi:10.3390/molecules14051713
molecules
ISSN 1420-3049

www.mdpi.com/journal/molecules

 Article
Cytotoxic Components of Pereskia bleo (Kunth) DC. (Cactaceae) Leaves

Sri Nurestri Abdul Malek 1,*, Sim Kae Shin 1, Norhanom Abdul Wahab 2 and Hashim Yaacob 3
1 Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
2 Institute of Postgraduate Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia
3 International University College of Nursing, B-27-6, Block B, Jaya One, No 72A Jalan Universiti, 46000 Petaling Jaya, Selangor, Malaysia
* Author to whom correspondence should be addressed: E-mail: srimalek@um.edu.my; Tel.: +603-79677119; Fax: +603-79674178.
Received: 17 March 2009; in revised form: 7 April 2009 / Accepted: 4 May 2009 /
Published: 6 May 2009
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Abstract: Dihydroactinidiolide (1) and a mixture of sterols [campesterol (2), stigmasterol (3) and β-sitosterol (4)], together with the previously isolated individual compounds β-sitosterol (4), 2,4-di-tert-butylphenol (5), α-tocopherol (6), phytol (7) were isolated from the active ethyl acetate fraction of Pereskia bleo (Kunth) DC. (Cactaceae) leaves.
Cytotoxic activities of the above mentioned compounds against five human carcinoma cell lines, namely the human nasopharyngeal epidermoid carcinoma cell line (KB), human cervical carcinoma cell line (CasKi), human colon carcinoma cell line (HCT 116), human hormone-dependent breast carcinoma cell line (MCF7) and human lung carcinoma cell line (A549); and non-cancer human fibroblast cell line (MRC-5) were investigated. Compound 5 possessed very remarkable cytotoxic activity against KB cells, with an IC50 value of 0.81μg/mL. This is the first report on the cytotoxic activities of the compounds isolated from Pereskia bleo.
Keywords: Pereskia bleo; Cactaceae; cytotoxic activity; cell lines
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Introduction
The leaves of Pereskia bleo (Kunth) DC. (Cactaceae) are used traditionally in Malaysia for the treatment of cancer, high blood pressure, diabetes and diseases associated with heumatism and inflammation. They are also used as remedy for the relief of gastric pain, ulcers and for revitalizing the body [1]. The leaves are generally consumed by the locals either raw or taken as a concoction brewed from fresh leaves.
Chemical investigations on Pereskia bleo are rare in comparison to other Pereskia species, as there were only three phytochemical and biological studies reported for this plant. The earliest phytochemical study was by Doetsch et al. [4], who reported the isolation of four alkaloids, namely 3,4-dimethoxy-β-phenethylamine, mescaline, 3-methoxytyramine and tyramine. An investigation by Tan et al. [2] reported that the methanol extract of Pereskia bleo possessed cytotoxic effects against T-47D cells and the cell death was found to be apoptotic in nature, mainly via the activation of the caspase-3 and c-myc pathways. A more recent investigation by Er et al. [3] indicated the antiproliferative and mutagenic activities of aqueous and methanol extracts of Pereskia bleo leaves against mouse mammary cancer cells (4T1) or normal mouse fibroblast cells (NIH/3T3). In our previous cytotoxicity screenings on Pereskia bleo [5], the EtOAc fraction possessed notably high cytotoxic effects against selected human carcinoma cell lines, but exerted no damage to a non-cancer human fibroblast cell line (MRC-5). The active EtOAc fraction was found to contain β-sitosterol (4), 2,4-ditert- butylphenol (5), α-tocopherol (6) and phytol (7) [5]. As part of our ongoing research on Pereskia bleo, a pure compound and a mixture of sterols were also isolated from the leaves of Pereskia bleo.
In the present study, we report further progress in ongoing research on Pereskia bleo, which led to the isolation and identification of dihydroactinidiolide (1) and a mixture of sterols [campesterol (2), stigmasterol (3) and β-sitosterol (4)] and cytotoxic investigation on all isolated compounds against five human carcinoma cell lines, namely the human nasopharyngeal epidermoid carcinoma cell line (KB), human cervical carcinoma cell line (CasKi), human colon carcinoma cell line (HCT 116), hormonedependent breast carcinoma cell line (MCF7) and human lung carcinoma cell line (A549) and noncancer human fibroblast cell line (MRC-5).

Results and Discussion
Extraction and isolation of pure compounds and the sterol mixture
β-Sitosterol (4), 2,4-di-tert-butylphenol (5), α-tocopherol (6) and phytol (7) were obtained from Pereskia bleo as previously described by Sri Nurestri et al. [5]. On repeated chromatographic purification of the active EtOAc fraction, a red viscous oil and white colored needles were obtained and identified as dihydroactinidiolide and a mixture of sterols.
Dihydroactinidiolide (1), red viscous oil; EI-MS m/z (%): 180 [M] + (15), 137 (8), 111 (100), 109, 67. Compound 1 was identified by comparison of its mass spectral data with NIST mass-spectral library [21] and other reported spectroscopic data [6-8].
The mixture of sterols appeared as white colored needles that according to GC-MS analyses consisted of campesterol (2, 14.33%), stigmasterol (3, 4.95%) and β-sitosterol (4, 70.21%). Compound 2 (campesterol); EI-MS m/z (%): 400 (42, [M+]), 382 (34), 367 (20), 315 (30), 289 (30), 55 (100). The mass spectral data was also in agreement with reported data [9]. Stigmasterol (3) was identified by GC-MS analysis and by comparison of its mass spectral data [EI-MS m/z (%): 412 (16, [M+]), 394 (4), 369 (2), 351 (6), 271 (16), 255 (22), 229 (5), 55 (100)] with reported data [9]. Compound 4 (ß-sitosterol); EI-MS m/z (%): 414 (100, M+), 396 (57), 381 (43). ß-sitosterol (4) was identified by GC-MS analysis as well as comparison of its mass spectral data with reported data [10].

The structures of compounds 1-7 are illustrated in Figure 1.

In vitro Neutral Red cytotoxicity assay
The in vitro cytotoxicity assay was carried out using a Neutral Red cytotoxicity assay as previously described by Borenfreund and Puerner [11] with some modifications; this test determines the accumulation of the Neutral Red dye in the lysosomes of viable and uninjured cells.
The results of cytotoxicity screening of the components are summarized in Table 1. It is generally known that ethnomedical data substantially increases the chances of finding active plants relative to a random approach [2]. The consequence is that, once having found activity in the plant from the ethopharmacological observation (e.g. raw or concoction brewed from the plant leaves shows effect for cancer treatment), there is a desire to determine the chemical structures of the compounds that are responsible for the activity, as not all the compounds in the extracts have the same activity.

However, the observed activity might be due to synergism between compounds present in the plant extract. The synergism among these compounds which contribute to the cytotoxic activity, is not only dependent on the concentration of the compounds, but also on the structure and interaction(s) between the compounds [27]. This can explain the differences in the cytotoxic effect between crude extracts and isolated compounds against the same cell lines, as shown in our earlier report [5]. For example, the cytotoxic effect of the crude methanol extract on the KB cell lines showed an IC50 of 6.5 μg/mL and such impressive activity was supported by some of the isolated compounds [dihydroactinidiolide (1), 2,4-di-tert-butylphenol (5), α-tocopherol (6) and phytol (7)]. In contrast, the cytotoxic effect of the crude methanol extract on the MCF7 cell line gave IC50 of 39.0 μg/mL (mild) whilst two isolated compounds 2,4-di-tert-butylphenol (5) and α-tocopherol (6), showed good inhibitory activities with IC50 values of 5.75 and 7.5 μg/mL, respectively.

2,4-Di-tert-butylphenol (5) displayed very remarkable cytotoxic activity against KB cells with an IC50 value of 0.81 μg/mL and strong cytotoxicity against MCF7 (IC50 5.75 μg/mL), A549 (IC50 6 μg/mL) and CasKi cells (IC50 4.5 μg/mL). This in vitro data of 2,4-di-tert-butylphenol (5) support the findings that phenolic antioxidants exert cytoctoxic activity against cancer cells [14, 15]. 2,4-Di-tertbutylphenol (5) is an antioxidant widely used in the plastics industries, and its presence in plants cannot readily be explained biogenetically. It is more probable that the plant accumulated this compound from the soil it grew in, that might have contained the compound. In our experience, this compound has also been detected in other plants like Termitomyces heimi, Pleurotus sajor-caju and Hericium erinaceus collected from different locations to where the Pereskia bleo leaves were obtained (unpublished data from our group of researchers working on Termitomyces heimi, Pleurotus sajor-caju and Hericium erinaceus). The observation of 2,4-di-tert-butylphenol (5) in our study is not an isolated case, as it has also been reported to exist in natural sources by other researchers [29-31]. To support our finding that 2,4-di-tert-butylphenol (5) is not an artifact, an extraction on Pereskia bleo was repeated using redistilled methanol and ethyl acetate. GC-MS analysis on the ethyl acetate extract still showed the presence of 2,4-di-tert-butylphenol (5) representing the major component of the total ethyl acetate extract. This shows that 2,4-di-tert-butylphenol (5) is present in the extract itself and not a solvent artifact.
Other constituents in the plant also contribute to its cytotoxic activity as shown by α-tocopherol (6), phytol (7) and dihydroactinidiolide (1). In the present study, α-tocopherol (6), which is a dietary antioxidant, displayed pronounced cytotoxicity against CasKi (IC50 6 μg/mL) and A549 (IC50 6 μg/mL). The result obtained here is consistent with other reports [37-40, 47-50] on cytotoxic activities in other cell lines. Lesser number of investigations described an opposite effect [44-46]. There was no report on the cell lines that were used in this study. According to Table 1, phytol (7) demonstrated strong activity against KB cells (IC50 7.1 μg/mL). The cytotoxicity data showed in this report thus supports our hypothesis in our previous report [5] that phytol might be responsible for the remarkable cytotoxic effect of the EtOAc fraction against the KB cancer cell lines. In this study, dihydroactinidiolide (1) demonstrated strong cytotoxic effect against HCT116 with IC50 5.0 μg/mL. Dihydroactinidiolide (1) is structurally similar to the C11-terpene lactones that arise from the biological or oxidative degradation of carotenoids and has been isolated from various plants and insect sources. It has also been identified as the flavor molecule in tea and tobacco [6-8].
Sterols are important constituents of all eukaryotes and play a vital role in plant cell membranes. In addition to their cholesterol lowering effect, plant sterols may possess anti-atherosclerosis [32-33], antibacterial [36], anti-inflammation [34] and anti-oxidation activities [35]. In the present study, β-sitosterol (4) and the mixture of sterols [campesterol (2), stigmasterol (3) and β-sitosterol (4)] did not display cytotoxic effects against the tested cell lines. The results obtained here were in agreement with published data [16-20]. There have been reports that plant sterols are able to stimulate estrogen dependent cancer cells in vitro (e.g. Ju et al. [42]). The MCF7 cell line used in this study was purchased from ATCC. It was reported that MCF7 cells from ATCC were unaffected by estrogen or antiestrogen [43]. Thus, the result showed that the sterols do inhibit the growth of MCF7 cells.
Doxorubicin which is clinically used for the treatment of a great variety of cancer disease [24-26] was used as the positive control in present study. Based on the result, it can be concluded that doxorubicin is not only cytotoxic against all the human cancer cell lines tested, but also the non-cancer human cell line. This result supports the statement that doxorubicin is a potent cytostatic drug which is applied for the treatment of cancer diseases but the routine use of this drug could bring major adverse effect [24]. Although the cytotoxicity of the isolated compounds and mixture of Pereskia bleo are not as effective as doxorubicin, they however have low toxicity against normal MRC5 cell line in comparison to doxorubicin. The use of the isolated compounds as single anticancer agents would not merit consideration. However, their use in combination with cytotoxic therapeutic drugs might reduce the adverse effects of some of these drugs. Support for this suggestion is provided by Amir et al. [41], who reported that in addition to having potent antitumor properties as single agents, natural products have also demonstrated potential synergy with established cytotoxic therapeutic drugs in pre-clinical studies. At this stage, it is not possible to justify the use of isolated compounds in comparison to doxorubicin in the treatment of cancer. A more comprehensive investigation is required.

Experimental
General
GCMS analysis was performed using a Agilent Technologies 6980N gas chromatography equipped with a 5979 Mass Selective Detector (70 eV direct inlet); a HP-5ms (5% phenylmethylsiloxane) capillary column (30.0 m x 250 μm x 0.25 μm) initially set at 60C for 10 minutes, then programmed to 230C at 3C min-1and held for 1 min at 230C using helium as the carrier gas at a flow rate of 1 mL min-1. The total ion chromatogram obtained was auto integrated by ChemStation and the components were identified by comparison with an accompanying mass spectral database [21]. Thin layer chromatography (TLC) analyses were carried out using precoated TLC plates 60 F254 (20.25 mm thickness) purchased from Merck and were visualized in UV light (254 and/or 343 nm) and/or iodine vapour.

Plant sample collection and identification
The fresh leaves of Pereskia bleo were collected from Petaling Jaya, Selangor, Malaysia in September 2006. They were identified by Professor Dr. Halijah Ibrahim of Institute of Biological Sciences, Faculty of Science, University of Malaya, Malaysia and a voucher specimen (SN01-06) was deposited at the herbarium of the Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.

Extraction and isolation of pure compound and mixture
β-Sitosterol (4), 2,4-Di-tert-butylphenol (5), α-tocopherol (6) and phytol (7) were isolated from Pereskia bleo as previously described by Sri Nurestri et al. [5]. Compound 1 and mixture of sterols were obtained according to the following procedure. Dried, ground leaves (1,050.56 g) of Pereskia bleo were extracted with MeOH (3x 1.5 L). The MeOH-containing extract obtained was initially treated with charcoal, then filtered over Celite® and the filtrate was evaporated under reduced pressure to give a crude MeOH extract (99.44 g). Treatment with charcoal was necessary to remove the high amounts of chlorophyll present in the extract, which interfered with chromatographic separation efforts. The crude MeOH extract was then further partitioned between EtOAc and H2O in a separating funnel. The EtOAc-soluble layer was concentrated in vacuo giving an 18.34 g EtOAc fraction, which was subjected to flash silica gel column chromatography (Si-gel CC) eluting with CHCl3 (10 L), and then with CHCl3-MeOH [9:1 (9 L)] and finally MeOH (7.6 L). The CHCl3 fraction was concentrated to give a dark brown residue (3.47 g). The brown residue was subjected to a Si-gel CC initially eluting with a gradient of hexane followed by hexane enriched with increasing percentages of CH2Cl2, monitoring with TLC. The volume of each fraction was 25 mL. The mixture of sterols (20.5 mg) was obtained from the fraction upon elution with CH2Cl2-hexane (3.5: 6.5). Further elution with CH2Cl2 yielded a mixture (206.7 mg) containing 1. Purification of 1 was obtained through preparative-TLC using CHCl3 as the developing solvent to yield pure compound 1 (5.4 mg).

Cell lines and culture medium 
Human nasopharyngeal epidermoid carcinoma cell line (KB), human cervical carcinoma cell line (CasKi), human colon carcinoma cell line (HCT 116), human hormone-dependent breast carcinoma cell line (MCF7), human lung carcinoma cell line (A549) and non-cancer human fibroblast cell line (MRC-5) were purchased from the American Tissue Culture Collection (ATCC, USA). KB cells were maintained in Medium 199 (Sigma), CasKi, A549 and MCF7 cells in RPMI 1640 medium (Sigma), HCT 116 in McCOY’S 5A Medium (Sigma) and MRC-5 cells in EMEM (Eagle Minimum Essential Medium) (Sigma), supplemented with 10% foetal bovine serum (FBS, PAA Lab, Austria), 100 μg/mL penicillin or streptomycin (PAA Lab, Austria) and 50 μg/mL of fungizone (PAA Lab, Austria). The cells were cultured in a 5% CO2 incubator (Shel Lab water-jacketed) kept at 37°C in a humidified atmosphere.

In vitro Neutral Red cytotoxicity assay
The Neutral Red cytotoxicity assay is based on the initial protocol described by Borenfreund and Puerner [11] with some modifications. Briefly, the cells (1x104/well) were seeded in 96-well microtiter plates (Nunc) and allowed to grow for 24 hours before treatment. After 24 hours of incubation, the cells were treated with six different concentrations (0.1-100 μg/mL) of test compounds, in three replicates. The plates were further incubated for 72 h at 37°C in a 5% CO2 incubator. A stock solution was initially obtained by dissolving the test compounds in DMSO. Further dilution to different tested concentrations were then carried out ensuring that the final concentration of DMSO in the test and control wells was not in excess of 1% (v/v). No effect due to the DMSO was observed. Doxorubicin was used as the positive control. The well containing untreated cells was the negative control. At the end of the incubation period, the media were replaced with medium containing 50 μg/mL of Neutral Red. The plates were incubated for another 3 hours to allow for uptake of the vital dye into the lysosomes of viable and injured cells. After the incubation period, the media were removed and cells were washed with the neutral red washing solution. The dye was eluted from the cells by adding 200 μL of Neutral Red resorb solution and incubated for 30 minutes at room temperature with rapid agitation on a microtiter plate shaker. Dye absorbance was measured at 540 nm using a spectrophotometer ELISA plate reader. The average data from triplicates were expressed in terms of killing percentage relative to negative control. The percentage of inhibition (%) of each of the test samples was calculated according to the following formula:
where OD control: Optical Density of negative control; OD sample: Optical Density of sample

Cytotoxicity of each sample is expressed as IC50 value. The IC50 value is the concentration of test compounds that cause 50 % inhibition or cell death, averaged from the three experiments, and was obtained by plotting the percentage inhibition versus concentration of test compounds. According to US NCI plant screening program, a plant extract is generally considered to have active cytotoxic effect if the IC50 value, following incubation between 48 to 72 hours, is 20 μg/mL or less, while it is 4 μg/mL or less for pure compounds [12, 13, 22, 23]. However, we recognized that whether an IC50 value corresponds to a significant or non-significant cytotoxicity depends on the sensitivity of the cell line.

Conclusions
In conclusion, and depending on the cell lines used, the cytotoxic activities observed for Pereskia bleo [5] are ascribable to the presence of the active compounds 1, 5, 6 and 7. Although the cytotoxicity of these compounds and mixture are not as effective as doxorubicin, in comparison to the latter they have low toxicity against normal MRC5 cell line. The cytotoxicity assay used in the present study could only provide important preliminary data to help select plant extracts or isolated compounds with potential antineoplastic properties for future work. A detailed investigation on the mechanism of cell death would provide more convincing evidence. An investigation into this phenomenon is now underway and will be reported in due course. The resulting information will certainly contribute to a better understanding of the anti-carcinogenic activity of the natural constituents in Pereskia bleo.
Pereskia bleo has been traditionally used for the treatment of cancer and the findings of the current study thus provide scientific validation on the use of the leaves of Pereskia bleo. In view of the increasing popular consumption of medicinal plants as alternative therapy, it is therefore necessary to conduct serious research to support the therapeutic claims and also to ensure that the plants are indeed safe for human consumption.

Acknowledgements
This work was supported by a research fund from the University of Malaya (Vote F PS056/2007C) and the Ministry of Science, Technology and Innovation (MOSTI) (E-sciencefund 1202032026). We are also grateful to Prof A. Hamid A Hadi for use of his laboratory space.

References

1. Goh, K.L. Malaysian herbaceous plants (in Chinese); Advanco Press: Malaysia, 2000; p.142.
2. Tan, M.L.; Sulaiman, S.F.; Najimuddin, N.; Samian, M.R.; Tengku Muhammad, T.S. Methanolic extract of Pereskia bleo (Kunth) DC. (Cactaceae) induces apoptosis in breast carcinoma, T47-D cell line. J. Ethnopharmacol. 2005, 96, 287-294.
3. Er, H.M.; Cheng, E.; Radhakrishnan, A.K. Anti-proliferative and mutagenic activities of aqueous and methanol extracts of leaves from Pereskia bleo (Kunth) DC leaves. J. Ethnopharmacol. 2007, 113, 448-456.
4. Doetsch, P.W.; Cassady, J.M.; McLaughlin, J.L. Cactus alkaloids: XL. Identification of mescaline and other β-phenethylamines in Pereskia, Pereskiopsis and Islaya by use of fluorescamine conjugates. J. Chromatogr. A 1980, 189, 79-85.
5. Sri Nurestri, A.B.; Norhanom, A.W.; Hashim, Y.; Sim, K.S.; Hong, S.L.; Lee, G.S.; Syarifah, N.S.A.R. Cytotoxic activity of Pereskia bleo (Cactaceae) against selected human cell lines. Int. J. Cancer Res. 2008, 4, 20-27.
6. Eidman, K.F.; MacDougall, B.S. Synthesis of loliolide, actinidiolide, dihydroactinidiolide, and aeginetolide via cerium enolate chemistry. J. Org. Chem. 2006, 71, 9513-9516.
7. Borse, B.B.; Rao, L.J.M.; Nagalakshmi, S.; Krishnamurthy, N. Fingerprint of black teas from India: identification of the regio-specific characteristics. Food Chem. 2002, 79, 419-424.
8. Huang, L.F.; Zhong, K.J.; Sun, X.J.; Wu, M.J.; Huang, K.L.; Liang, Y.Z.; Guo, F.Q.; Li, Y.W. Comparative analysis of the volatile components in cut tobacco from different locations with gas chromatography-mass spectrometry (GC-MS) and combined chemometric methods. Analytica Chimica Acta 2006, 575, 236-245.
9. Gutierrez, R.M.P. Identification of triterpenoids in chloroform extract of Agarista Mexicana by MS and NMR. Nat. Prod. Res. 2006, 20, 181-185.
10. Nes, W.; David, N.; Robert, A.; Benson, M. Carbon-13 NMR studies on sitosterol biosynthesized from [13C] mevalonates. Phytochemistry 1992, 31, 805-811.
11. Borenfreund, E.; Puerner, J.A. A simple quantitative procedure using monolayer culture for toxicity assays. J. Tissue Cult. Meth. 1984, 9, 7-9.
12. Geran, R.I.; Greenberg, N.H.; McDonald, M.M.; Schumacher, A.M.; Abbott, B.J. Protocols for screening chemical agents and natural products against animal tumor and other biological systems. Cancer Chemother. Rep. 1972, 3, 17-19.
13. Swanson, S.M.; Pezzuto, J.M. Bioscreening technique for cytotoxicity potential and ability to inhibit macromolecule biosynthesis. In Drug bioscreening: drug evaluation techniques in pharmacology; Thompson, E.B., Ed.; VCH Publishers: New York, NY, USA, 1990; pp. 273-297.
14. Russo, A.; Cardile, V.; Ioannes, A.D.; Garbarino. Effect of litreol on the viability of human cancer cells. Chem. Biol. Interact. 2009, 179, 178-184.
15. Kozubek, A.; Tyman, J.H. Resorcinolic lipids, the natural non-isoprenoid phenolic amphiphiles and their biological activity. Chem. Rev. 1999, 99, 1-26.
16. Awad, A.B.; Downie, A.C.; Fink, C.S. Inhibition of growth and stimulation of apoptosis by β-sitosterol treatment of MDA-MB-231 human breast cancer cells in culture. Int. J. Mol. Med. 2000, 5, 541-545.
17. Block, S.; Baccelli, C.; Tinant, B.; Meervelt, L.V.; Rozenberg, R.; Jiwan, J.L.; Habib, L.; Gabriel, P.G.; De, M.C.; Joelle, Q.L. Diterpenes from the leaves of Croton zambesicus. Phytochemistry 2004, 65, 1165-1171.
18. Bennani, H.; Drissi, A.; Giton, F.; Kheuang, L.; Fiet, J.; Adlouni, A. Antiproliferative effect of polyphenols and sterols of virgin argan oil on human prostate cancer cell lines. Cancer Det. Prev. 2007, 31, 64-69.
19. Jackson, S.J.; Houghton, P.J.; Retsas, S.; Photiou, A. In vitro cytotoxicty of norviburtinal and isopinnatal from Kigelia pinnata against cancer cell lines. Planta Med. 2000, 66, 758.
20. Moghadasian, M.H. Pharmacological properties of plant sterols: in vivo and in vitro observations. Life Sci. 2000, 67, 605-615.
21. NIST 05 MS Library; Agilent Technologies: Palo Alto, CA, USA, 2002.
22. Lee, C.C.; Houghton, P. Cytotoxicity of plants from Malaysia and Thailand used traditionally to treat cancer. J. Ethnopharmacol. 2005, 100, 237-243.
23. Boik, J. Natural compounds in cancer therapy; Oregon Medical Press: Princeton, MN, USA, 2001; pp. 25.
24. Gille, L.; Kleiter, M.; Willmann, M.; Nohl, H. Paramagnetic species in the plasma of dogs with lymphoma prior to and after treatment with doxorubicin An ESR study. Biochem. Pharmacol. 2002, 64, 1737-1744.
25. Carter, S.K. Adriamycin: a review. J. Natl. Cancer Inst. 1975, 55, 1256-1274.
26. Khanna, C.; Lund, E.M.; Redic, K.A.; Hayden, D.W.; Bell, F.W.; Goulland, E.L.; Klausner, J.S. Randomized controlled trial of doxorubicin versus dactinomycin in multi agent protocol for treatment of dogs with malignant lymphoma. J. Am. Vet. Med. Assoc. 1998, 213, 985-990.
27. Houghton, P.J.; Raman, A. Laboratory Handbook for the Fractionation of Natural Extracts;Chapman & Hall: London, UK, 1998; pp. 1-13.
28. Masatoshi, S.; Toshiko, A.; Kazue, S.; Mariko, I.; Ikuko, I.; Hiroshi, S.; Ichiro, Y.; Seiichiro, F. Radical production and cytotoxic activity of tert-butyl-substituted phenols. Vitro Mol. Toxicol. 2001, 14, 53-63.
29. Yoon, M.-A.; Jeong, T.-S.; Park, D.-S.; Xu, M.-Z.; Oh, H.-W.; Song, K.-B.; Lee, W.S.; Park, H.- Y. Antioxidant effects of quinoline alkaloids and 2,4-di-tert-butylphenol isolated from Scolopendra subspinipes. Biol. Pharm. Bull. 2006, 29, 735-739.
30. Nogueira, P.C. de L.; Bittrich, V.; Shepherd, G.J.; Lopes, A.V.; Marsaiolia, A.J. The ecological and taxonomic importance of flower volatiles of Clusia species (Guttiferae). Phytochemistry 2001, 56, 443-452.
31. Rana, V.S.; Blazquez, M. A. Chemical constituents of Gynura cusimbua aerial parts. J. Essent. Oil Res. 2007, 19, 21-22.
32. Moghadasian, M.H.; McManus, B.M.; Pritchard, P.H.; Frohlich, J.J. “Tall oil”- derived phytosterols reduce atherosclerosis in ApoE-deficient mice. Arterioscler. Thromb. Vasc. Biol.
1997, 17, 119-126.
33. Moghadasian, M.H.; McManus, B.M.; Godin, D.V.; Rodrigues, B.; Frohlich, J.J. Proatherogenic and antiatherogenic effects of probucol and phytosterols in apolipoprotein E-deficient mice: possible mechanisms of action. Circulation 1999, 99, 11733-1739.
34. Bouic, P.J. The role of phytosterols and phytosterolins in immune modulation: a review of the past 10 years. Curr. Opin. Clin. Nutr. Metab. Care 2001, 4, 471-475.
35. Rensburg, S.J.; Daniels, W.M.; Zyl, J.M.; Taljaard, J.J. A comparative study of the effects of cholesterol, beta-sitosterol, beta- sitosterol glucoside, dehydroepiandrosterone sulphate and
melatonin on in vitro lipid peroxidation. Metab. Brain Dis. 2000, 15, 257-265.
36. Yasukawa K.; Takido, M.; Matsumoto, T.; Takeuchi, M.; Nakagawa, S. sterol and triterpene derivatives from plants inhibit the effects of tumour promoter and sitosterol and betulinic acid inhibit tumour formation in mouse skin two-stage carcinogenesis. Oncology 1991, 41, 72-76.
37. Hao, J.; Zhang, B.; Liu, B.; Lee, M.; Hao, X.; Reuhl, K.R.; Chen, X.; Yang, C.S. Effect of α-tocopherol, N-acetylcysteine and omeprazole on esophageal adenocarcinoma formation in a rat surgical model. Int. J. Cancer 2009, 124, 1270-1275.
38. Bermudez, Y.; Ahmadi, S.; Lowell, N.E.; Kruk, P.A. Vitamin E suppreses telomerase activity in ovarian cancer cells. Cancer Det. Prev. 2007, 31, 119-128.
39. Lamson, D.W.; Brignall, M.S. Antioxidants in cancer therapy: their actions and interactions with oncologic therapies. Altern. Med. Rev. 1999, 4, 30-329.
40. Drisko, J.A.; Chapman, J.; Hunter, V.J. The use of antioxidant therapies during chemotherapy. Gynecol. Oncol. 2003, 88, 434-439.
41. Amir, D.; Sunil, K.; Gautam, S.; Bharat, B. A. Back to basics: how natural products can provide the basis for new therapeutics. Expert Opin. Investig. Drugs 2007, 16, 1753-1773.
42. Ju, Y.H.; Clausen, L.M.; Allred, K.F.; Almada, A.L.; Helferich, W.G. ß-Sitosterol, ß-sitosterol glucoside, and a mixture of ß-sitosterol and ß-sitosterol glucoside modulate the growth of estrogen-responsive breast cancer cells in vitro and in ovariectomized athymic mice. J. Nutr.2004, 134, 1145-1151.
43. Osborne, C.K.; Hobbs, K.; Trent, J.M. Biological differences among MCF-7 human breast cancer cell lines from different laboratories. Breast Cancer Res. Treat. 1987, 9, 111-121.
44. Bolt, M.W.; Racz, W.J.; Brien, J.F.; Massey, T.E. Effects of vitamin E on cytotoxicity of
amiodarone and N-desethylamiodarone in isolated hamster lung cells. Toxicology 2001, 166, 109-118.
45. Przybyszewski, W.M.; Kopec-Szlezak, J.; Malec, J. Protection of L5178Y cells by vitamin E against acute hydroxyurea-induced cytotoxic events. Cancer Lett. 1987, 34, 337-344.
46. Xie, R.-N.; Shen, X.-N.; Zhong, W.-J.; Zhou, X.-F.; Ying, X.-P. Effect of lycopene alone or with Vitamin E on BALB/c-3T3 cell transformation induced by benzo (a) pyrene. Huanjing Yu Zhiye Yixue (in Chinese) 2004, 21, 124-126.
47. Al-Sherbini, E-S. A.M.; El Noury, A.H.; El Rouby, M.N. Vitamin E (α-tocopherol) enhances the PDT action of hematoporphyrin derivatives on cervical cancer cells. Med. Laser Appl. 2009, 24, 65-73.
48. Kogure, K.; Manabe, S.; Suzuki, I.; Tokumura, A.; Fukuzawa, K. Cytotoxicity of α-tocopheryl succinate, malonate and oxalate in normal and cancer cells in vitro and their anti-cancer effects on mouse melanoma in vivo. J. Nutr. Sci. Vitaminol. 2005, 51, 392-397.
49. Campbell, S.E.; Stone, W.L.; Lee, S.; Whaley, S.; Yang, H.; Qiu, M.; Goforth, P.; Sherman, D.; McHaffie, D.; Krishnan, K. Comparative effects of RRR-alpha- and RRR-gamma-tocopherol on proliferation and apoptosis in human colon cancer cell lines. BMC Cancer 2006, 6, 13.
50. Wu, X.-X.; Kakehi, Y.; Jin, X.-H.; Inui, M.; Sugimoto, M. Induction of apoptosis in human renal cell carcinoma cells by vitamin E succinate in caspase-independent manner. Urology 2009, 73, 193-199.

Sample Availability: Samples are available from the authors.

© 2009 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.
This article is an open-access article distributed under the terms and conditions of the Creative
Commons Attribution license (http://creativecommons.org/licenses/by/3.0).

Thứ Năm, 15 tháng 8, 2013

PERESKIA SAECNAROSA/PERESKIA BLEO – THIÊN Ý




PERESKIA SAECNAROSA – PERESKIA BLEO – THIÊN Ý
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Cây thuộc họ xương rồng và là loài cây xương rồng với . Là một chi nguyên thủy trong họ xương rồng.
Pereskia có nguồn gốc từ Hàn Quốc nhưng có thể dễ dàng tìm thấy ở Malaysia, Thái Lan và Indonesia. Cây có thể sống gần như bất kỳ loại điều kiện ngoại trừ khu vực lạnh, dưới ánh mặt trời sinh trưởng tốt hơn và phát triển nhanh ở khí hậu nhiệt đới. 15-20 loài Pereskia có thể được tìm thấy tại Nam Phi, Trung Mỹ và Tây Ấn Độ.
Pereskia được sử dụng để chữa bệnh ung thư đặc biệt là ung thư ruột kết, ung thư mi và một số bệnh ung thư khác.
ba cách để chế biến sử dụng loại thảo mộc này, đầu tiên bạn có thể lấy 2 lá Pereskia ngâm với nước ấm, để trong 2 phút uống như trà. Thứ hai, bạn có thể ăn sống hoặc cách thứ ba là xay nhuyễn nhiều lá  làm thành nước uống.Hương vị có thể là đăng đắng, nhưng hiệu quả trong việc chữa bệnh ung thư, huyết áp cao bệnh tiểu đường.
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This plant is from a cactus family which probably one of cactus species with leaf. It was a primitive genus in cactus family. Pereskia is originated from Korea but can be easily found in Malaysia, Thailand and Indonesia. This plant can live almost any type of condition except cold area. This plant is better kept under the sun and fast grow in Tropical tempereture. There is 15-20 species of Pereskia which can be located in South Africa,Middle of America and West India.
Pereskia is use to cure cancer especially Colon cancer, Nose cancer and several others deceases. There is three way to prepare the herbs, first you can take 2 slices of Pereskia Leafs and mix it with warm water, let it for 2 minutes and drink it as a tea. Secondly you can eat it raw or the third way is make a jus from it by blended several leafs of Pereskia. The taste might be bitter, but its capable to cure cancer, high blood and diabetes.


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Hoạt động gây độc tế bào của Pereskia Bleo đối với những dòng tế bào chọn lọc

GIỚI THIỆU
Pereskia bleo , thường được gọi là Jarum Tujuh Bilah (trong tiếng Mã Lai) và Cak Sing Cam (ở Trung Quốc) tên tiếng địa phương, thuộc họ Cactaceae. Pereskia bleo là một loại cây bụi gai có hoa màu đỏ da cam và đã được sử dụng như phương thuốc tự nhiên trong các bệnh liên quan đến ung thư, hoặc ăn sống hoặc pha biến trộn thành một hỗn hợp từ lá cây tươi. Lá cũng được sử dụng như một loại rau. Pereskia bleo được cho là có tác dụng chống ung thư, chống thấp khớp, chống loét và chống viêm nhiễm. Nó cũng được sử dụng như biện pháp khắc phục để làm giảm các cơn đau dạ dày và phục hồi cơ thể (Goh, 2000).
Chỉ có hai báo cáo về nghiên cứu sinh học và hóa lý cho loại cây này. Nghiên cứu hóa lý sớm nhất là bởi Doetsch et al. (1980) đã báo cáo sự cô lập bốn alkaloid, cụ thể là 3,4-dimetoxy-β-phenethylamine, mescaline, 3 methoxytyramine và tyramine từ Pereskia bleo. Nghiên cứu gần đây của Tan và  cộng sự. (2005) báo cáo chiết xuất methanol của Pereskia bleo cho hiệu ứng gây độc tế bào chống lại các tế bào T-47D và tế bào chết được tìm thấy khiến chúng tự hủy trong tự nhiên chủ yếu thông qua con đường kích hoạt của caspase-3 và c-myc.
Theo quan điểm của việc sử dụng truyền thống của Pereskia bleo trong các bệnh liên quan ung thư và điều tra của Tan và  cộng sự. (2005) đề nghị việc sử dụng tiềm năng của Pereskia bleo trong điều trị ung thư vú , cũng như từ đó cần thiết để tiếp tục mở rộng phạm vi nghiên cứu này đến các dòng tế bào ung thư khác. Một cuộc điều tra về tác động gây độc tế bào của methanol và chiết xuất phân đoạn của Pereskia bleo chống lại dòng tế bào ung thư chọn lựa có tên là: Human Nasopharyngeal Epidermoid Carcinoma Cell Line (KB), Human Cervical Carcinoma Cell Line (CasKi), Human Colon Carcinoma Cell Line (HCT 116), Hormone-Dependent Breast Carcinoma Cell Line (MCF7 và non-cancer Human Fibroblast Cell Line (MRC-5) sử dụng xét nghiệm in vitro trung tính màu đỏ gây độc tế bào được theo đuổi và kết quả được báo cáo trong sự tiếp cận thông tin này. Ngoài ra, xác định chiết tách các hợp chất ly trích hiện diện trong phần hoạt động cũng được thực hiện.
KẾT LUẬN:
Pereskia bleo, được chọn để nghiên cứu này dựa trên việc nó được sử dụng như một loại thuốc cổ truyền, cho thấy hoạt động ức chế đáng kể đối với các tế bào KB chiết bằng Acetate ethyl cho thấy hoạt động gây độc tế bào rất tốt đối với tế bào KB ung thư biểu mô biểu bì mũi họng, tuy nhiên, một nghiên cứu về cơ chế truyền tín hiệu như chu kỳ tế bào và tế bào chết sẽ cung cấp một bằng chứng thuyết phục hơn. Một cuộc điều tra hiện tượng này đang được tiến hành. Ngoài ra cũng cho thấy không có hiện tượng gây độc tế bào đối với các dòng tế bào bình thường, việc sử dụng cây này bởi người dân địa phương để điều trị ung thư sẽ có sự hỗ trợ của khoa học. Do đó, Pereskia bleo được tiếp tục phát triển để sử dụng trong điều trị các ung thư biểu bì mũi họng. Nghiên cứu về ảnh hưởng của các thành phần được ly trích (bằng tác nhân acetate ethyl) trên các tế bào KB đang tiến hành. Các thông tin này chắc chắn sẽ đóng góp cho một sự hiểu biết tốt hơn về các hoạt động chống ung thư của các thành phần tự nhiên trong Pereskia bleo.
XÁC NHẬN
Nghiên cứu này được hỗ trợ bởi một quỹ nghiên cứu từ Đại học Malaya (Vote F F0155/2005D) và Bộ Khoa học, Công nghệ và Đổi mới (MOSTI) (e-sciencefund 1202032026). Chúng tôi cũng xin cảm ơn Giáo sư A. Hamid A Hadi cho sử dụng không gian trong phòng thí nghiệm của mình.


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Cytotoxic Activity of Pereskia bleo (Cactaceae) Against Selected Human Cell Lines
INTRODUCTION
Pereskia bleo, commonly known as Jarum Tujuh Bilah (in Malay) and Cak Sing Cam (in Chinese) by the locals, belongs to the family Cactaceae. Pereskia bleo is a spiny shrub with distinct orange-red flowers and has been used as natural remedy in cancer-related diseases, either eaten raw or taken as a concoction brewed from fresh plant. The leaves were also consumed as vegetables by some people. Pereskia bleo is believed to have anti-cancer, anti-tumor, anti-rheumatic, anti-ulcer and anti-inflammatory properties. They are also used as remedy for the relief of gastric pain and for revitalising the body (Goh, 2000).
There were only two phytochemical and biological studies reported for this plant. The earliest phytochemical study was by Doetsch et al. (1980) who reported the isolation of four alkaloids, namely 3,4-dimethoxy-β-phenethylamine, mescaline, 3-methoxytyramine and tyramine from Pereskia bleo. A more recent investigation by Tan et al. (2005) reported that the methanol extract of Pereskia bleo possesed cytotoxic effect against T-47D cells and cell death was found to be apoptotic in nature mainly via the activation of caspase-3 and c-myc pathways.
In view of the traditional use of Pereskia bleo in cancer-related diseases and the initial investigation by Tan et al. (2005) which suggested the potential use of Pereskia bleo in the treatment of breast cancer, it was thus necessary to further expand this area of research to other cancer cell lines. An investigation on the cytotoxic effects of the methanol and fractionated extracts of Pereskia bleo against selected human cancer cell lines, namely the Human Nasopharyngeal Epidermoid Carcinoma Cell Line (KB), Human Cervical Carcinoma Cell Line (CasKi), Human Colon Carcinoma Cell Line (HCT 116), Hormone-Dependent Breast Carcinoma Cell Line (MCF7) and non-cancer Human Fibroblast Cell Line (MRC-5) using an in vitro neutral red cytotoxicity assay was thus pursued and the findings is reported in this communication. In addition, identification of isolated compounds present in the active fraction was also performed.
CONCLUSIONS
Pereskia bleo, which was selected for the present study based on its traditional medicinal use, showed remarkable inhibitory activity against KB cells. The ethyl acetate fraction showed very good cytotoxic activity against the nasopharyngeal epidermoid carcinoma KB cells but however, a study on the mechanism of signal transduction such as cell cycle and cell death would provide a more convincing evidence. An investigation into this phenomena is now underway. In addition this fraction also showed no cytotoxicity against the normal cell line; if this also occurs in vivo, the use of this plant by locals for cancer treatment would have scientific support. Thus, Pereskia bleo could be further developed for use in the treatment of the nasopharyngeal epidermoid carcinoma. Studies on the effect of the isolated components (present in the ethyl acetate fraction) on KB cells are now underway. The resulting information will certainly contribute to a better understanding of the anti-carcinogenic activity of the natural constituents in Pereskia bleo.
ACKNOWLEDGMENT
This study was supported by a research fund from the University of Malaya (Vote F F0155/2005D) and the Ministry of Science, Technology and Innovation (MOSTI) (e-sciencefund 1202032026). We are also grateful to Prof A. Hamid A Hadi for use of his laboratory space