In vitro genotoxicity of the West African anti-malarial herbal Cryptolepis sanguinolenta and its major alkaloid cryptolepine

Cryptolepine (CLP), the major alkaloid of the West African anti-malarial herbal Cryptolepis sanguinolenta (Periplocaceae) is a DNA intercalator that exhibits potent toxicity to a variety of mammalian cells in vitro. We have hypothesized that the DNA intercalating properties of cryptolepine could trigger genetic damage in mammalian cells. The objective of the present study was therefore to assess the ability of both cryptolepine (CLP) and the traditional anti-malarial formulation, the aqueous extract from the roots (CSE) to induce mutation at the hprt locus and micronuclei (MN) formation in V79, a Chinese hamster fibroblast cell line commonly used in genetic toxicity studies. CSE at a high concentration (50 microg/ml) induced an apparent significant ten fold increase in mutant frequency compared to vehicle control (mean of 38 versus 4 mutant clones/10(6) surviving cells) but, this concentration of CSE was very toxic (<15% cell survival). CLP did not appear to be mutagenic in the dosage range used (up to 2.5 microM, equivalent to 1.1 microg/ml). However, after 24h treatment of V79 cells both CSE and CLP induced a dose-dependent increase in micronuclei of 4.15% and 6.43% (25 microg/ml CSE and 2.5 microM, equivalent to 1.1 microg/ml CLP, respectively) compared to 0.36% in vehicle control. These results show that treatment of mammalian cells with CSE and CLP can lead to DNA damage and we suggest that the routine use of CSE and the potential use of CLP derivatives in malaria chemotherapy could carry a genotoxic risk.     

Cigarette smoke extract inhibits expression of peroxiredoxin V and increases airway epithelial permeability

Inhaled cigarette smoke induces oxidative stress in the epithelium of airways. Peroxiredoxin V (PRXV) is a potent antioxidant protein, highly expressed in cells of the airway epithelium. The goal of our study was to determine whether cigarette smoke extract (CSE) influenced expression of this protein in airway epithelia in vivo and in vitro. In Sprague-Dawley rats, we determined effects of CSE on airway epithelial permeability, mRNA levels and expression of PRXV protein. Exposure of isolated tracheal segment in vitro to 20% CSE for 4 h resulted in development of increased permeability to albumin, significantly reduced mRNA levels for PRXV, and reduced amounts of PRXV protein in the epithelium. In cultures of the airway epithelial cell lines (Calu-3, JME), primary airway cell culture (cow), and alveolar epithelial cells A549, CSE also significantly decreased transepithelial electrical resistance and expression of PRXV protein, and induced glutathione and protein oxidation. To demonstrate functional importance of PRXV, we exposed clones of HeLa cells with siRNA-downregulated PRXV to hydrogen peroxide, which resulted in increased rate of cell death and protein oxidation. CSE directly downregulates expression of functionally important antioxidant enzyme PRXV in the epithelial cells of airways, which represents one pathophysiological mechanism of cigarette smoke toxicity.     

Antimalarial,antiplasmodial and analgesic activities of root extract of Alchornea laxiflora

Context: Alchornea laxiflora (Benth.) Pax. &; Hoffman (Euphorbiaceae) root decoctions are traditionally used in the treatment of malaria and pain in Nigeria.

Objective: To assess the antimalarial, antiplasmodial and analgesic potentials of root extract and fractions against malarial infections and chemically-induced pains.

Material and methods: The root extract and fractions of Alchornea laxiflora were investigated for antimalarial activity against Plasmodium berghei infection in mice, antiplasmodial activity against chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of Plasmodium falciparum using SYBR green assay method and analgesic activity against experimentally-induced pain models. Acute toxicity study of the extract, cytotoxic activity against HeLa cells and GCMS analysis of the active fraction were carried out.

Results: The root extract (75–225?mg/kg, p.o.) with LD₅₀ of 748.33?mg/kg exerted significant (p?P. berghei infection in suppressive, prophylactive and curative tests. The root extract and fractions also exerted moderate activity against chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of P. falciparum with the ethyl acetate fraction exerting the highest activity with IC₅₀ value of 38.44?±?0.89?μg/mL (Pf 3D7) and 40.17?±?0.78?μg/mL (Pf INDO). The crude extract was not cytotoxic to HeLa cells with LC₅₀ value >100?μg/mL. The crude extract and ethyl acetate fraction exerted significant (p?Discussion and conclusions: These results suggest that the root extract/fractions of A. laxiflora possess antimalarial, antiplasmodial and analgesic potentials and these justify its use in ethnomedicine to treat malaria and pain.     

A comparative study of electronic cigarette vapor extracts on airway-related cell lines in vitro

The use of electronic cigarettes (ECs) is rapidly increasing worldwide; however, scientific evidence regarding EC cytotoxicity is limited. The aim of this study was to evaluate the acute cytotoxicity of EC vapor extract (ECE) on airway-related cells in vitro. Cigarette smoke extract (CSE), vapor extract of fifteen brands/flavors of ECs and the extract from the E-vehicle (propylene glycol and glycerin) was collected. Extracts, in concentrations of 100–12.5%, were added to human bronchial epithelial (BEAS-2B, IB3-1 and C38), fibroblast (Wi-38) and macrophage (J774 and THP-1) cell lines. Viability was assessed after 24?h using a standard XTT assay. Viability of <70% of control (no extract) was considered cytotoxic according to UNI EN ISO 10993-5 standards. CSE displayed a concentration-dependent influence on cell viability across all four cell lines with 100% producing the most toxic effect, therefore validating the model and indicating higher cytotoxicity than in ECEs. ECEs did reduce viability although this was not correlated with nicotine content or the E-vehicle. However, several flavors proved cytotoxic, with variation between different brands and cell lines. These data indicate that not all ECs are the same and that use of a particular flavor or brand may have differing effects. The cell line used is also an important factor. More research is crucial to ascertain the health effects of different ECs before they can be accepted as a safe alternative to tobacco cigarettes.     

Toxicological profile of cereulide, the Bacillus cereus emetic toxin, in functional assays with human, animal and bacterial cells.

Some strains of the endospore-forming bacterium Bacillus cereus produce a heat-stable ionophoric peptide, cereulide, of high human toxicity. We assessed cell toxicity of cereulide by measuring the toxicities of crude extracts of cereulide producing and non-producing strains of B. cereus, and of pure cereulide, using cells of human, animal and bacterial origins. Hepatic cell lines and boar sperm, with cytotoxicity and sperm motility, respectively, as the end points, were inhibited by 1 nM of cereulide present as B. cereus extract. RNA synthesis and cell proliferation in HepG2 cells was inhibited by 2 nM of cereulide. These toxic effects were explainable by the action of cereulide as a high-affinity mobile K+ carrier. Exposure to cereulide containing extracts of B. cereus caused neither activation of CYP1A1 nor genotoxicity (comet assay, micronucleus test) at concentrations below those that were cytotoxic (0.6 nM cereulide). Salmonella typhimurium reverse mutation (Ames) test was negative. Exposure of Vibrio fischeri to extracts of B. cereus caused stimulated luminescence up to 600%, independent on the presence of cereulide, but purified cereulide inhibited the luminescence with an IC(50% (30 min)) of 170 nM. Thus the luminescence-stimulating B. cereus substance(s) masked the toxicity of cereulide in B. cereus extracts to V. fischeri.     

Inhibition of mutagenesis and transformation by root extracts of Panax ginseng in vitro

The root extract of Panax ginseng was investigated for its inhibitory effects on DNA synthesis, mutagenicity, and cellular transformation using V79 and NIH 3T3 cells. DNA synthesis measured by the [3H]thymidine incorporation into V79 Chinese hamster lung cells was significantly decreased by the addition of ginseng extract (0-1 microgram/ml) to the medium. However, ginseng extract was found to increase the rate of DNA excision repair synthesis in V79 cells in response to treatment with UV radiation or methyl methanesulfonate. The extract also showed decreased mutation frequency when mutagenicity was examined using V79 cells at the hypoxanthine-guanine phosphoribosyl transferase locus as resistance to 6-thioguanine after exposure to methyl methanesulfonate. We also found that the components of ginseng extract continue to exert an inhibitory effect on the transformation of NIH 3T3 cells initiated by 3-methylchloanthrene, methyl methanesulfonate, and 1-methyl-3-nitro-1-nitrosoguanidine.     

Cytotoxic evaluation and induction of mitochondria-mediated apoptosis in human leukaemia HL-60 cells by Carissa spinarum stem isolate

Objective To evaluate Carissa spinarum stem isolate for its anti‐cancer therapeutic potential. Methods The n‐butanol fraction of aqueous extract from Carissa spinarum stem was assessed for its cytotoxic and pro‐apoptotic activity. Key findings We report for the first time the anti‐cancer potential of C. spinarum stem aqueous extract (CSE) and its n‐butanol fraction (CSF). Both inhibited cell proliferation of various human cancer cell lines in which leukaemia HL‐60 cells treated with CSF showed maximum growth inhibition having an inhibitory concentration (IC₅₀) value of 34.58 ± 0.91 µg/ml. In addition, CSF induced concentration‐dependent apoptosis in HL‐60 cells as measured by various end‐points (e.g. Annexin V binding, DNA laddering, apoptotic body formation and an increase in hypodiploid subG0 DNA content). Moreover, persistent levels of reactive oxygen species caused translocation of Bax to mitochondria and Bcl‐2 degradation, which led to loss of mitochondrial membrane potential and release of cytochrome c to the cytosol. These events were associated with significant activation of caspase‐3, caspase‐6 and caspase‐9 leading to poly (ADP‐ribose) polymerase cleavage. Conclusion All the above parameters revealed that CSF induced apoptosis through the mitochondrial dependent pathway in HL‐60 cells.     

Mouse aldo-keto reductase AKR7A5 protects V79 cells against 4-hydroxynonenal-induced apoptosis

We have developed transgenic Chinese hamster V79 cell lines in order to examine the potential for a mouse aldo-keto reductase, AKR7A5, to protect against the toxicity of 4-hydroxynonenal (4-HNE) and related toxic aldehydes. Stable expression of mouse AKR7A5 in V79 cells conferred four-fold increased resistance to 4-HNE cytotoxicity using the MTT assay compared to empty vector-transfected V79 cells. Cells expressing AKR7A5 showed a decrease in mutation rate compared to control cells in the presence of 4-HNE as measured by HGPRT mutagenicity assay. Furthermore, the cells expressing AKR7A5 showed decreased 4-HNE-induced caspase-3 activity in both a time and dose-dependent manner compared to control cells. These results show that in V79 cells 4-HNE mediates apoptosis via caspase-3 activation and that the AKR7A5 enzyme is able to metabolize 4-HNE in cells, thereby attenuating 4-HNE-induced apoptosis. AKR7A isozymes may therefore be important in protecting against toxic aldehydes derived from lipid peroxidation in vivo.     

Evaluation of in vitro antioxidant,anticancer and in vivo antitumour activity of Termitomyces clypeatus MTCC 5091

Context: Termitomyces clypeatus (Lyophyllaceae) is a filamentous edible mushroom, having ethnomedicinal uses. However, information about the antioxidant, anticancer and antitumour properties of this mushroom remains to be elucidated.

Objective: The study examines the in vitro antioxidant, anticancer and in vivo antitumour activity of T. clypeatus.

Materials and methods: Antioxidant activity was evaluated with seven in vitro assays. Cytotoxicity of T. clypeatus was tested against a panel of cancer cells lines including U373MG, MDA-MB-468, HepG2, HL-60, A549, U937, OAW-42 and Y-79 using MTT assay. The antitumour activity of aqueous extract was evaluated against Ehrlich ascites carcinoma (EAC) tumour model in Swiss albino mice.

Results: HPLC analysis of aqueous extract revealed the presence of sugar entities. Termitomyces clypeatus showed excellent in vitro antioxidant activity. Termitomyces clypeatus was found cytotoxic against all cancer cells, among which it showed higher activity against U937 (IC₅₀ 25?±?1.02?μg/mL). Treatment of EAC-bearing mice with varied doses of aqueous extract significantly (p?<?0.01) reduced tumour volume, viable tumour cell count and improved haemoglobin content, RBC count, mean survival time, tumour inhibition and % increase life span. The enhanced antioxidant status in treated animals was evident from the decline in the levels of lipid peroxidation, increased levels of glutathione, catalase and superoxide dismutase.

Discussion: The analyzed data indicate that the aqueous extract of T. clypeatus exhibits significant antitumour activity, which might be due to the antioxidant effects on EAC bearing hosts.

Conclusion: Termitomyces clypeatus possesses anticancer activity, valuable for application in food and drug products.     

柞树提取液的遗传毒性

目的 探讨柞树提取液的遗传毒性.方法 采用微核实验、精子畸形实验、Ames实验和V79细胞基因突变实验考察柞树提取液的遗传毒性.Ames实验设柞树提取液6.25,12.5,25,50和100 mg组,直接计数培养基上各菌株的回变菌落数.V79细胞基因突变实验设柞树提取液2.5,5.0和10 g·L-1组,直接观察集落数...     

Artemisinin reduces human melanoma cell migration by down-regulating αVβ3 integrin and reducing metalloproteinase 2 production

Artemisinin and its derivatives are well known antimalarial drugs, particularly useful after resistance to traditional antimalarial pharmaceuticals has started to occur in Plasmodium falciparum. In recent years, anticancer activity of artemisinin has been reported both in vitro and in vivo. Artemisinin has inhibitory effects on cancer cell growth and anti-angiogenetic activity. In the present investigation, we analyzed the inhibitory effects of artemisinin on migratory ability of melanoma cell lines (A375P and A375M, low and medium metastatic properties, respectively). We demonstrate that artemisinin induces cell growth arrest in A375M, and affects A375P cells viability with cytotoxic and growth inhibitory effects, while it was not effective in contrasting proliferation of other tumor cell lines (MCF7 and MKN). In addition, artemisinin affected the migratory ability of A375M cells by reducing metalloproteinase 2 (MMP-2) production and down-regulating αvβ3 integrin expression. These findings introduce a potential of artemisinin as a chemotherapeutic agent in melanoma treatment.     

Comparative analysis of cytotoxic effect of aqueous cinnamon extract from Cinnamomum zeylanicum bark with commercial cinnamaldehyde on various cell lines

A thorough comparative analysis of cytotoxic effect of an aqueous cinnamon extract (ACE) from the bark of Cinnamomum zeylanicum L. (Lauraceae) with that of commercially available cinnamaldehyde was performed on various human as well as mouse cell lines and primary cells. The aqueous cinnamon extract (ACE) proved to be more cytotoxic to cancerous cells at concentrations just above 0.16?mg/mL (containing 1.28 μM cinnamaldehyde) around which the commercial cinnamaldehyde (1.6 μM) had no cytotoxic effect. At a critical concentration of 1.28?mg/mL (containing 10.24 μM cinnamaldehyde), ACE treatment resulted in 35-85% growth inhibition of the majority of the cancerous cells, whereas at a similar concentration (10 μM) commercial cinnamaldehyde treatment resulted in 30% growth inhibition of only SK-N-MC cells with no effect on other cell lines. These results suggest that ACE had a significant inhibitory effect on the majority of cancer cells and thus may prove to be a chemotherapeutic agent.     

Cytotoxicity of bioactive polymeric fractions from grape cell culture on human hepatocellular carcinoma, murine leukemia and non-cancerous PK15 kidney cells.

Previously, we isolated two fractions (TP-4 and TP-6) from grape cell culture that were potent catalytic inhibitors in a human DNA topoisomerase II assay for cancer chemoprevention. The objectives of this study were to further assess cytotoxicity of these fractions on cancerous and non-cancerous cells, and to subfractionate and characterize the composition of TP-6, a fraction that was selectively cytotoxic to carcinoma cell lines. Both TP-4 and TP-6 provided significant cytotoxicity to L1210 mouse leukemia cells. Only TP-6, a procyanidin-rich fraction, significantly reduced viability in HepG2 human liver cancer cells, yet unlike resveratrol, caused no cytotoxicity to non-cancerous PK15 pig kidney cells. After further subfractionation of TP-6 (maximal toxicity = 67.2%; ED(50) = 50.5 microM), the cytotoxicity of subfractions on HepG2 cells was TP-6-5 (maximal toxicity=71.8%; ED(50) = 14.1 microM), TP-6-6 (maximal toxicity=64.3%; ED(50) = 67.0 microM), and TP-6-4 (maximal toxicity = 27.6%; ED(50) = 118.0 microM) in descending order. LC-ESI/MS data suggested that cytotoxicity of these procyanidin mixtures to HepG2 cells was proportional to the degree of polymerization. Because TP-6 and its subfractions were selectively cytotoxic to cancerous cell lines tested, they warrant further investigation as potential natural anticancer agents.     

Cytotoxic effect of the red beetroot (Beta vulgaris L.) extract compared to doxorubicin (Adriamycin) in the human prostate (PC-3) and breast (MCF-7) cancer cell lines

Previous cancer chemoprevention studies from our laboratories and by other investigators have demonstrated that the extract of red beetroot (Beta vulgaris L.), the FDA approved red food color E162, can be effective in suppressing the development of multi-organ tumors in experimental animals. To further explore this finding, we have compared the cytotoxic effect of the red beetroot extract with anticancer drug, doxorubicin (adriamycin) in the androgen-independent human prostate cancer cells (PC-3) and in the well-established estrogen receptor-positive human breast cancer cells (MCF-7). This red colored anticancer antibiotic was selected for comparative cytotoxic study because its chemical structure with a planar configuration of an aromatic chromophore attached to a sugar molecule is remarkably similar to that of betanin, the beetroot extract constituent primarily responsible for its red color. Both doxorubicin and the beetroot extract exhibited a dose-dependent cytotoxic effect in the two cancer cell lines tested. Although the cytotoxicity of the beetroot extract was significantly lower when compared to doxorubicin, it continued to decrease the growth rate of the PC-3 cells (3.7% in 3 days vs. 12.5% in 7 days) when tested at the concentration of 29 μg/ml. In contrast, doxorubicin, at the same concentration level, completely inhibited the growth of the PC-3 cells in three days. Similarly, comparative studies in the normal human skin FC and liver HC cell lines showed that the beetroot extract had significantly lower cytotoxic effect than doxorubicin (8.6% vs. 100%, respectively, at 29 μg/ml concentration of each, three-day test period). The results suggest that betanin, the major betacyanin constituent, may play an important role in the cytotoxicity exhibited by the red beetroot extract. Further studies are needed to evaluate the chemopreventive potentials of the beetroot extract when used alone or in combination with doxorubicin to mitigate the toxic side-effects of the latter.     

Cytotoxicity of trans-dehydrocrotonin from Croton cajucara on V79 cells and rat hepatocytes.

The cytotoxicity of trans-dehydrocrotonin (DHC), an antiulcerogenic diterpene from Croton cajucara (Euphorbiaceae), was assessed on a V79 fibroblast cell line and on rat hepatocytes. Three independent endpoints for cytotoxicity were evaluated: DNA content, MTT reduction and neutral red uptake (NRU). For the V79 cells IC50 values of 253 and 360 microM were obtained for the NRU and MTT tests. The cytotoxic effect of DHC was time exposure dependent and no ability to recover after treatment was observed. For the rat hepatocytes IC50 values of 8, 300 and 400 microM for the MTT, DNA and NRU assays were obtained. The greater toxicity observed for the MTT test was inhibited when the experiment was performed using non-fresh hepatocytes in an age-dependent fashion. The treatment of V79 cells with the conditioned medium resulting after hepatocyte incubation with DHC showed an enhancement of MTT reduction without any evident toxic effects on fibroblasts. These results suggest that DHC has basal cytotoxic effects as observed on V79 fibroblasts and expresses a selective cytotoxicity after its metabolization by the hepatocytes. The bioactivation of DHC is mediated by cytochrome P450 and could generate metabolites that have no toxicity for V79 fibroblasts.     

Cytotoxicity of Vinca minor

Vinca minor L. (Apocynaceae) is a medicinal plant that has long been used to treat cerebral and memory disorders in European folk medicine. Furthermore, it contains more than 50 alkaloids, some of them having bisindole structure such as the antineoplastic alkaloids present in Catharanthus roseus (L.) G. Don (Apocynaceae). In this study, the plant’s alkaloid extract was divided into three fractions and the cytotoxic effects on cell proliferation of HT-29, Caco-2, T47D, and NIH/3T3 cell lines were examined. All alkaloid fractions showed a dose-dependent cytotoxic effect on the cell lines. IC₅₀ values confirmed that the growth and proliferation of NIH/3T3 cells were less affected in comparison to other cell lines.     

CYP2D6 increases toxicity of the designer drug 4-methylthioamphetamine (4-MTA)

4-Methylthioamphetamine (4-MTA) belongs to a group of new amphetamine derivatives that is usually sold as "ecstasy" or "flatliners" on the illicit drug market. Large interindividual differences in 4-MTA mediated toxicity have been reported in humans. Therefore, we tested whether CYP2D6 or its variant alleles as well as CYP3A4 influence the susceptibility to 4-MTA. For this purpose, we used the colony formation assay with Chinese hamster lung fibroblast V79 cells expressing human wild-type CYP2D6 (CYP2D6*1), the low activity alleles CYP2D6*2, CYP2D6*9, as well as human CYP3A4. The obtained results showed that the expression of wild type CYP2D6*1 clearly enhanced the susceptibility to the cytotoxic effects of 4-MTA compared with the parental cells devoid of CYP-dependent enzymatic activity. Toxicity in V79 CYP2D6*1 was also higher compared to the V79 cell lines expressing the low activity alleles CYP2D6*2 and CYP2D6*9. In contrast to CYP2D6, the CYP3A4 isoenzyme did not enhance 4-MTA toxicity. In conclusion, our results suggest that CYP2D6 rapid metabolizers may be more susceptible to 4-MTA toxicity than CYP2D6 poor metabolizers.     

Effects of antioxidants on oxidative stress and inflammatory responses of human bronchial epithelial cells exposed to particulate matter and cigarette smoke extract

Particulate matter (PM) is a type of air pollutant that induces adverse health effects, including acute exacerbation of chronic obstructive pulmonary disease (COPD). However, the effects of co-exposure to PM and cigarette smoke extract (CSE) on bronchial epithelial cells remain unknown. This study investigated the cytotoxic and pro-inflammatory effects of combined exposure to PM and CSE on bronchial epithelial cells, and assessed the potential of antioxidants to inhibit CSE/PM-induced oxidative stress and inflammation. Exposure of epithelial cells to PM or CSE induced cytotoxicity, inflammation, and oxidative stress, all of which were dramatically increased when cells were exposed to the combination of CSE and PM. Importantly, the adverse effects of CSE/PM exposure were suppressed when cells were treated with sulforaphane (SFN) or sulforaphane N-acetylcysteine (SFNAC). Furthermore, SFN and SFNAC suppressed the CSE/PM-induced pro-inflammatory cytokine production and expression of inflammatory genes. Combined PM and CSE exposure further activated the MAPK and Nrf2 signaling pathways. SFN and SFNAC attenuated CSE/PM-induced epithelial toxicity through the ERK/JNK signaling pathway-dependent inhibition of inflammation. Moreover, SFN and SFNAC suppressed ROS generation by activating antioxidant enzymes and Nrf2 signaling. Therefore, SFN and SFNAC could be a promising approach to prevent or mitigate the exacerbation of pulmonary diseases caused by PM and other air pollutants.     

Evaluation of cytotoxic and mutagenic effects of Coriolus versicolor and Funalia trogii extracts on mammalian cells

This study examined the in vitro cytotoxic activities of standardized aqueous bioactive extracts prepared from Coriolus versicolor and Funalia trogiiATCC 200800 on HeLa and fibroblast cell lines using a MTT (3-[4,5-dimetiltiazol-2-]-2-5-difeniltetrazolium bromide) cytotoxicity assay. F. trogii and C. versicolor extracts were cytotoxic to both cell lines. At 10 microL treatment level, F. trogii and C. versicolor extracts inhibited proliferation of HeLa cancer cells by 71.5% and 45%, respectively, compared with controls. Toxicity was lower toward normal fibroblasts. In the latter case, treatment at 10 microL level with F. trogii and C. versicolor extracts reduced cell proliferation by 51.3% and 38.7%, respectively. In separate experiments, the mitotic index (MI) obtained with 3 microL treatment level of unheated extracts of the two fungi was comparable to the MI value obtained by treatment with 4 microg/mL MMC (anticancer agent mitomycin-C). A significant induction of sister chromatid exchange (SCE) was observed in normal cultured lymphocytes treated with MMC (4 microg/mL). MMC treatment reduced replication index compared with treatment with unheated F. trogii extract and negative controls (p < 0.001). In contrast to MMC, F. trogii extracts did not affect the proliferation of human lymphocytes compared with controls (p > 0.05). Laccase and peroxidase enzyme activities in F. trogii extract were implicated in their inhibitory effect on cancer cells. F. trogii extract was concluded to have antitumor activity.     

Effects of bioactive compounds from carrots (Daucus carota L.), polyacetylenes, beta-carotene and lutein on human lymphoid leukaemia cells

New therapies for leukaemia are urgently needed. Carrots have been suggested as a potential treatment for leukaemia in traditional medicine and have previously been studied in other contexts as potential sources of anticancer agents. Indicating that carrots may contain bioactive compounds, which may show potential in leukaemia therapies. This study investigated the effects of five fractions from carrot juice extract (CJE) on human lymphoid leukaemia cell lines, together with five purified bioactive compounds found in Daucus carota L, including: three polyacetylenes (falcarinol, falcarindiol and falcarindiol-3-acetate) and two carotenoids (beta-carotene and lutein). Their effects on induction of apoptosis using Annexin V/PI and Caspase 3 activity assays analysed via flow cytometry and inhibition of cellular proliferation using Cell Titer Glo assay and cell cycle analysis were investigated. Treatment of all three lymphoid leukaemia cell lines with the fraction from carrot extracts which contained polyacetylenes and carotenoids was significantly more cytotoxic than the 4 other fractions. Treatments with purified polyacetylenes also induced apoptosis in a dose and time responsive manner. Moreover, falcarinol and falcarindiol-3-acetate isolated from Daucus carota L were more cytotoxic than falcarindiol. In contrast, the carotenoids showed no significant effect on either apoptosis or cell proliferation in any of the cells investigated. This suggests that polyacetylenes rather than beta-carotene or lutein are the bioactive components found in Daucus carota L and could be useful in the development of new leukemic therapies. Here, for the first time, the cytotoxic effects of polyacetylenes have been shown to be exerted via induction of apoptosis and arrest of cell cycle.