ABSTRACT
Psychedelic fungi have experienced a surge in interest in recent years. Most notably, the fungal secondary metabolite psilocybin has shown tremendous promise in the treatment of various psychiatric disorders. The mushroom species that produce this molecule are poorly understood. Here we sought to examine for the first time, the response of a psilocybin-producing species Psilocybe cubensis to casing (peat moss and vermiculite) and supplementation with gypsum (calcium sulfate dihydrate), two common practices in commercial mushroom cultivation. Mycelial samples of genetically authenticated P. cubensis were used to inoculate popcorn grain bags. The fully colonized bags of popcorn grain (0.15 kg) were transferred to bins of 0.85 kg pasteurized horse manure, with or without 1 cm thick layer of casing and/or 5 % gypsum. Our results indicate that the use of a casing layer significantly increases the biological efficiency (161.5 %), by approximately four fold, in comparison to control (40.5 %), albeit with a slight delay (â¼2 days) for obtaining fruiting bodies and a somewhat reduced total tryptamine content (0.85 %) as gauged by High Performance Liquid Chromatography measurements. Supplementation with both casing and gypsum, however, appears to promote maximal yields (896.6 g/kg of dried substrate), with a biological efficiency of 89.6 %, while also maintaining high total tryptamine expressions (0.95 %). These findings, revealing methods for maximizing yield of harvest and expressions of psychoactive tryptamines, may prove useful for both home growers and commercial cultivators of this species, and ultimately support the growth of a robust industry with high quality natural products.
Subject(s)
Agaricales , Psilocybe , Psilocybin , Humans , Animals , Horses , Psilocybin/analysis , Calcium Sulfate , Vocalization, Animal , Tryptamines , Agaricales/chemistryABSTRACT
INTRODUCTION: Neglected tropical diseases (NTDs) in developing countries like the Caribbean, negatively affect multiple income-generating sectors, including the tourism industry upon which island states are highly dependent. Insect-transmitted NTDs include, but are not limited to, malaria, dengue and lymphatic filariasis. Control measures for these disease, are often ignored because of the associated cost. Many of the developing country members are thus retained in a financially crippling cycle, balancing the cost of prophylactic measures with that of controlling an outbreak.The purpose of the paper is to bring awareness to NTDs transmitted by insects of importance to humans, and to assess factors affecting such control, in the English-speaking Caribbean. METHOD: Comprehensive literature review on reports pertaining to NTDs transmitted by insects in the Caribbean and Latin America was conducted. Data search was carried out on PubMed, and WHO and PAHO websites. RESULTS AND CONCLUSION: Potential risk factors for NTDs transmitted by arthropods in the English-speaking Caribbean are summarised. The mosquito appears to be the main insect-vector of human importance within the region of concern. Arthropod-vectors of diseases of veterinary importance are also relevant because they affect the livelihood of farmers, in highly agriculture based economies. Other NTDs may also be in circulation gauged by the presence of antibodies in Caribbean individuals. However, routine diagnostic tests for specific diseases are expensive and tests may not be conducted when diseases are not prevalent in the population. It appears that only a few English-speaking Caribbean countries have examined secondary reservoirs of pathogens or assessed the effectivity of their insect control methods. As such, disease risk assessment appears incomplete. Although continuous control is financially demanding, an integrated and multisectoral approach might help to deflect the cost. Such interventions are now being promoted by health agencies within the region and various countries are creating and exploring the use of novel tools to be incorporated in their insect-vector control programmes.
ABSTRACT
The toxicological manifestation of many pollutants relies upon their binding to the aryl hydrocarbon receptor (AHR), and it follows a cascade of reactions culminating in an elevated expression of cytochrome P450 (CYP) 1 enzymes. CYP1A1 and CYP1B1 are associated with enhanced carcinogenesis when chronically exposed to certain polyaromatic hydrocarbons, and their inhibition may lead to chemoprevention. We evaluated dibenzyl trisulfide (DTS), expressed in the ethnomedical plant, Petiveria alliacea, for such potential chemoprevention. Using recombinant human CYP1A1 and CYP1B1 bactosomes on a fluorogenic assay, we first demonstrated that DTS moderately inhibited both enzymes with half maximal inhibitory concentration (IC50) values of 1.3 ± 0.3 and 1.7 ± 0.3 µM, respectively. Against CYP1A1, DTS was a reversible, competitive inhibitor with an apparent inhibitory constant (Ki) of 4.55 ± 0.37 µM. In silico molecular modeling showed that DTS binds with an affinity of -39.8 kJ·mol-1, situated inside the binding pocket, approximately 4.3 Å away from the heme group, exhibiting interactions with phenylalanine residue 123 (Phe-123), Phe-224, and Phe-258. Lastly, zebrafish (Danio rerio) embryos were exposed to 0.08-0.8 µM DTS from 24 to 96 h post fertilization (hpf) with the in vivo ethoxyresorufin-O-deethylase (EROD) assay, and, at 96 hpf, DTS significantly suppressed EROD CYP1A activity in a dose-dependent manner, with up to 60% suppression in the highest 0.8 µM exposure group. DTS had no impact on gene transcription levels for cyp1a and aryl hydrocarbon receptor 2 (ahr2). In co-exposure experiments, DTS suppressed CYP1A activity induced by both B[a]P and PCB-126, although these reductions were not significant. Taken together, these results demonstrate that DTS is a direct, reversible, competitive inhibitor of the carcinogen-activating CYP1A enzyme, binding in the active site pocket close to the heme site, and shows potential in chemoprevention.
Subject(s)
Benzyl Compounds/pharmacology , Cytochrome P-450 CYP1A1/antagonists & inhibitors , Cytochrome P-450 CYP1B1/antagonists & inhibitors , Cytochrome P-450 Enzyme Inhibitors/pharmacology , Receptors, Aryl Hydrocarbon/metabolism , Sulfides/pharmacology , Zebrafish Proteins/metabolism , Activation, Metabolic , Animals , Benzo(a)pyrene/metabolism , Benzo(a)pyrene/toxicity , Benzyl Compounds/metabolism , Binding Sites , Binding, Competitive , Catalytic Domain , Cytochrome P-450 CYP1A1/genetics , Cytochrome P-450 CYP1A1/metabolism , Cytochrome P-450 CYP1B1/genetics , Cytochrome P-450 CYP1B1/metabolism , Cytochrome P-450 Enzyme Inhibitors/metabolism , Gene Expression Regulation , Humans , Polychlorinated Biphenyls/metabolism , Polychlorinated Biphenyls/toxicity , Protein Binding , Receptors, Aryl Hydrocarbon/genetics , Sulfides/metabolism , Zebrafish/embryology , Zebrafish/metabolism , Zebrafish Proteins/geneticsABSTRACT
BACKGROUND: Annona muricata L. was identified as a popular medicinal plant in treatment regimens among cancer patients in Jamaica by a previously conducted structured questionnaire. Ethnomedically used plant parts, were examined in this study against human prostate cancer cells for the first time and mechanisms of action elucidated for the most potent of them, along with the active phytochemical, annonacin. METHODS: Nine extracts of varying polarity from the leaves and bark of A. muricata were assessed initially for cytotoxicity using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on PC-3 prostate cancer cells and the ethyl acetate bark (EAB) extract was identified as the most potent. EAB extract was then standardized for annonacin content using High-performance Liquid Chromatography - Mass Spectrometry (HPLC-MS) and shown to be effective against a second prostate cancer cell line (DU-145) also. The mode of cell death in DU-145 cells were assessed via several apoptotic assays including induction of increased reactive oxygen species (ROS) production, reduction of mitochondrial membrane potential, activation of caspases and annexin V externalization combined with morphological observations using confocal microscopy. In addition, the potential to prevent metastasis was examined via inhibition of cell migration, vascular endothelial growth factor (VEGF) and angiogenesis using the chorioallantoic membrane assay (CAM). RESULTS: Annonacin and EAB extract displayed selective and potent cytotoxicity against the DU-145 prostate carcinoma cells with IC50 values of 0.1 ± 0.07 µM and 55.501 ± 0.55 µg/mL respectively, without impacting RWPE-1 normal prostate cells, in stark contrast to chemotherapeutic docetaxel which lacked such selectivity. Docetaxel's impact on the cancerous DU-145 was improved by 50% when used in combination with EAB extract. Insignificant levels of intracellular ROS content, depolarization of mitochondrial membrane, Caspase 3/7 activation, annexin V content, along with stained morphological evaluations, pointed to a non-apoptotic mode of cell death. The extract at 50 µg/mL deterred cell migration in the wound-healing assay, while inhibition of angiogenesis was displayed in the CAM and VEGF inhibition assays for both EAB (100 µg /mL) and annonacin (0.5 µM). CONCLUSIONS: Taken together, the standardized EAB extract and annonacin appear to induce selective and potent cell death via a necrotic pathway in DU-145 cells, while also preventing cell migration and angiogenesis, which warrant further examinations for mechanistic insights and validity in-vivo.
Subject(s)
Annona , Carcinoma/drug therapy , Furans/therapeutic use , Lactones/therapeutic use , Plant Extracts/therapeutic use , Prostatic Neoplasms/drug therapy , Antineoplastic Agents/analysis , Antineoplastic Agents/therapeutic use , Carcinoma/metabolism , Caspases/metabolism , Cell Line, Tumor , Cell Movement/drug effects , Docetaxel/analysis , Docetaxel/therapeutic use , Drug Screening Assays, Antitumor , Drug Therapy, Combination , Furans/pharmacology , Humans , Lactones/pharmacology , Male , Membrane Potential, Mitochondrial/drug effects , Phytotherapy , Plant Bark/chemistry , Plant Extracts/pharmacology , Plant Leaves/chemistry , Prostatic Neoplasms/metabolism , Reactive Oxygen Species/metabolismABSTRACT
Melicoccus bijugatus Jacq (Mb) has been reported to have cardiovascular modulatory effects. In this study, we evaluated the antihypertensive effects and mechanism of action of Mb on NG-Nitro-L-arginine Methyl Ester (L-NAME) and Deoxycorticosterone Acetate (DOCA) rat models. Aqueous extract of Mb fruit (100 mg/kg) was administered for 6 weeks to rats by gavage and blood pressure was recorded. Effects of the extract on vascular reactivity was evaluated using isolated organ baths, and tissues were collected for biochemical and histological analysis. The systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) were significantly (P < 0.05) reduced with extract (100 mg/kg) administration and treatment compared to the hypertensive models. Mb (100 µg/mL) reduced the vascular contractility induced by phenylephrine (PE), and caused a dose-dependent relaxation of PE-induced contraction of aortic vascular rings. The vasorelaxation properties seemed to be endothelium dependent, as well as nitric oxide (NO) and guanylyl cyclase, but not prostaglandin dependent. Histomicrograph of transverse sections of the ventricles from the Mb group did not show abnormalities. The extract significantly (P < 0.05) reduced an L-NAME induced elevation of cardiac output and Creatine Kinase Muscle-Brain (CKMB), but had no significant impact on the activities of arylamine N-acetyltransferase. In conclusion, Mb significantly decreased blood pressure in hypertensive models. The extract possesses the ability to induce endothelium dependent vasodilation, which is dependent on guanylyl cyclase but not prostaglandins.
Subject(s)
Antihypertensive Agents/pharmacology , Hypotension/chemically induced , Plant Extracts/pharmacology , Sapindaceae/chemistry , Animals , Desoxycorticosterone Acetate/administration & dosage , Disease Models, Animal , Endothelium, Vascular/drug effects , Heart Rate/drug effects , Male , NG-Nitroarginine Methyl Ester/administration & dosage , Rats , Vasodilation/drug effectsABSTRACT
Cleome rutidosperma DC, commonly known in Jamaica as 'consumption-weed' is a plant traditionally used in folklore for treating tuberculosis and other infectious and chronic ailments. We evaluate for the first time the chemical composition and biological activities of the essential oil components of the complete aerial parts of this plant. The essential oil obtained by steam distillation (0.02%) was analyzed by a combination of gas chromatography-flame ionization detector (GC-FID), gas chromatography-mass spectroscopy (GC-MS) and retention index (RI). The volatile oil of C. rutidosperma was dominated by oxygenated diterpenes (67.6%); with (Z)-phytol (65.1%) being the single most abundant constituent. C. rutidosperma aerial essential oil exhibited moderate inhibition against the activity of recombinant arylamine N-acetyltransferase (NAT) from Mycobacterium marinum (IC50 22.20⯱â¯1.80⯵g/µL), while, racemic phytol had an inhibition with an IC50 of 22.33⯵g/µL⯱â¯0.50⯵g/µL, thus accounting for the NAT inhibition imparted by the crude oil. Inhibition of NAT, a key enzyme in mycobacterial growth may be the pathway in which phytol, shown in this study to interact with the active site using in-silico methods, renders its previously demonstrated anti-tubercular properties. The phytol rich essential oil also demonstrated antimicrobial activity against all nine human pathogenic bacteria and the fungus strain assayed, with the most significant inhibitory activity against Bacillus cereus and justifies the need for further evaluation and development of the essential oils from this plant.
Subject(s)
Cleome/chemistry , Oils, Volatile/chemistry , Plant Oils/chemistry , Bacteria/drug effects , Fungi/drug effects , Gas Chromatography-Mass Spectrometry , Jamaica , Microbial Sensitivity Tests , Molecular Docking Simulation , Oils, Volatile/pharmacology , Plant Oils/pharmacologyABSTRACT
Understanding the potential for adverse drug reactions (ADRs), from herb-drug interactions, is a key aspect of medicinal plant safety, with particular relevance for public health in countries where medicinal plant use is highly prevalent. We undertook an in-depth assessment of extracts of Hyptis verticillata Jacq., via its impact on activities of key cytochrome P450 (CYP) enzymes (CYPs 1A1, 1A2, 1B1, 3A4 and 2D6), its antioxidant properties (determined by DPPH assays) and chemical characterisation (using LC-MS). The dried plant aqueous extract demonstrated potent inhibition of the activities of CYPs 1A1 (7.6 µg/mL), 1A2 (1.9 µg/mL), 1B1 (9.4 µg/mL) and 3A4 (6.8 µg/mL). Further analysis of other crude extracts demonstrated potent inhibition of CYP1A2 activity for a dried plant ethanol extract (1.5 µg/mL), fresh plant ethanol extract (3.9 µg/mL), and moderate activity for a fresh plant aqueous extract (27.8 µg/mL). All four extracts demonstrated strong antioxidant activity, compared to the positive control (ascorbic acid, 1.3 µg/mL), with the dried plant ethanol extract being the most potent (1.6 µg/mL). Analysis of the dried plant aqueous extract confirmed the identity of seven phytochemicals, five lignans and two triterpenes. Individual screening of these phytochemicals against the activity of CYP1A2 identified yatein as a moderate inhibitor (71.9 µM), likely to contribute to the plant extract's potent bioactivity. Further analysis on the impact of this plant on key drug metabolizing enzymes in vivo appears warranted for likely ADRs, as well as furthering development as a potential chemopreventive agent.
Subject(s)
Cytochrome P-450 Enzyme Inhibitors/chemistry , Hyptis/chemistry , Plant Extracts/chemistry , Cytochrome P-450 CYP1A2/drug effects , Cytochrome P-450 Enzyme Inhibitors/pharmacology , Herb-Drug Interactions , Humans , Plant Extracts/pharmacologyABSTRACT
[This corrects the article DOI: 10.1371/journal.pone.0179673.].
ABSTRACT
PURPOSE: Patients' perspective of their treatment regime plays a vital role in its success. Recognizing the high prevalence of medicinal plant usage among Jamaicans at large, we investigated the engagement of such remedies by cancer patients, with the aim of uncovering self-medicating habits, perceptions and details of utilized plants. METHODS: A structured, interviewer-based questionnaire was administered to 100 patients attending the oncology and urology clinics at the University Hospital of the West Indies in Kingston, Jamaica. A method of convenience sampling was employed and the data were analyzed using summary statistics and statistical significance tests. RESULTS: A large proportion (n = 80, 80%) of interviewed patients, engaged medicinal plants in their treatment regimes. Such habits were independent of person's education, economic status and were higher among the 55-74 age groups (p < 0.05) compared with younger patients. The use of herbs was hinged on the patient's strong sense of tradition and positive perspective of herbal efficacy (88%), fueled by anecdotal accounts from fellow patients. Majority of such users (74.7%) were under concomitant treatment with a prescription medicine, and worryingly, only 15% of patients made their oncologists aware. Annona muricata L. and Petiveria alliacea L. were the most commonly used plants for treating breast and prostate cancers, respectively. CONCLUSION: A large proportion of Jamaican cancer patients use medicinal plants in self-medicating practices and their perceptions and habits need to be considered by physicians, in the design of safe and effective care regimes.
Subject(s)
Neoplasms/drug therapy , Phytotherapy , Plants, Medicinal , Adolescent , Adult , Aged , Female , Humans , Jamaica , Male , Middle Aged , Surveys and Questionnaires , Young AdultABSTRACT
The emergence of novel diseases spread by the Aedes aegypti mosquito in Jamaica and the Caribbean, has prompted studies on insecticide resistance towards effective management of the vector. Though Jamaica has been using the organophosphate insecticide malathion in its vector control program for more than 30 years, resistance to the pesticide has not been tested in over a decade. We analyzed resistance to malathion and the pyrethroid insecticide, permethrin on mosquitoes collected across St. Andrew, Jamaica, and analyzed the molecular basis of resistance. The Center for Disease Control (CDC) bioassay revealed that Ae. aegypti mosquitoes from St. Andrew, Jamaica were resistant to permethrin (15 µg/bottle) with mortalities at 0-8% at 30 minute exposure time, while contact with malathion (50 µg/bottle) revealed ≤ 50% mortality at 15 minutes, which increased to 100% at 45 minutes. The standard susceptible New Orleans (NO) strain exhibited 100% mortality within15 minutes. The activities of multifunction oxidases and p-nitro phenyl-acetate esterases were significantly greater in most Jamaican populations in comparison to the NO strain, while activities of glutathione-S-transferase, acetylcholinesterase, α-esterase and ß-esterase activity were relatively equal, or lower than that of the control strain. The frequency of knockdown resistance mutations in the voltage dependent sodium channel gene were measured. All collections were fixed for Cys1,534 while 56% of mosquitoes were Ile1,016/Val1,016 heterozygotes, and 33% were Ile1,016 homozygotes. Aedes aegypti from St. Andrew Jamaica are resistant to permethrin with variations in the mode of mechanism, and possibly developing resistance to malathion. Continued monitoring of resistance is critically important to manage the spread of the vector in the country.
Subject(s)
Aedes/drug effects , Insecticide Resistance/genetics , Insecticides/pharmacology , Malathion/pharmacology , Mosquito Control/methods , Permethrin/pharmacology , Animals , Jamaica , Mutation , Voltage-Gated Sodium Channels/geneticsABSTRACT
The chemical investigation of the organic extract of Canistrocarpus cervicornis, collected at Drunken Man's Cay at Port Royal, Jamaica, has led to the isolation of two new dolastane diterpenes 4R-acetoxy-8S,9S-epoxy-14S-hydroxy-7-oxodolastane (1) and 4R-hydroxy-8S,9S-epoxy-14S-hydroxy-7-oxodolastane (2) and the previously isolated dolastane (4R,9S,14S)-4,9,14-trihydroxydolast-1(15),7-diene (3) as a major diterpene constituent. The structures of the new compounds were elucidated by extensive spectroscopic analyses. Compounds 1-3 were evaluated for their cytotoxicity against human tumor cell lines PC3 and HT29. The results revealed that the dolastane diterpenes (1-3) displayed moderate, concentration dependent, cytotoxicity.
Subject(s)
Diterpenes/chemistry , Phaeophyceae/chemistry , Seaweed/chemistry , Cell Line, Tumor , HT29 Cells , HumansABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Artocarpus altilis (Parkinson ex F.A.Zorn, Fosberg) (Moraceae) are used in the management of hypertension; this study assessed the cardio-protective effects of the leaf extract on isoproterenol (ISO) induced myocardial damage in rats. MATERIAL AND METHODS: Twenty (20) adult male Sprague-Dawley rats (175-230g) were divided into 5 groups. Group 1 (Control), 2 (AA) received 50mg/Kg Artocarpus altilis (AA) only; 3 (ISO) received 85mg/Kg ISO only; 4 (ISO+AA/50) and 5 (ISO+AA/100) received 50 and 100mg/Kg AA respectively for 6 days, after induced with ISO twice (85mg/Kg) at a 24-h period. Blood pressure readings were taken before and after the administering of ISO using the tail cuff method. ECG was performed on anaesthetized rats. Cardiac contractility was measured in isolated right atrial muscles. Assessment of myocardial infarct (MI) size, heart/body weight ratio, biochemical, hematological and histo-morphological parameters were conducted at the end of seven days. An aqueous extract from leaves of A. altilis was analyzed for organic compounds using UHPLC mass spectrometry. RESULTS: ISO induced myocardial damage through an elevation of the heart rate (HR), infarct size and ECG distortions. Treatment with AA significantly (pË0.05) reduced heart/body weight ratio (49%), MI (96%), HR (27%), sympathovagal imbalance (36%) and serum cardiac biomarkers (AST, LDH, HDL, triglycerides and CCK) caused by ISO. AA decreased the beat frequency of isolated right atrium (11%) cause by ISO, an action similar to propranolol (beta-adrenergic antagonist; 20%), but showed no significant changes in the QTc intervals of the ECG (suggesting no cardio-toxic drug-herb interactions), Thirty nine compounds were detected using high resolution LC-MS analysis (HPLC-Orbitrap-APCI-MS) in the extract. Pure compounds, as gallic acid and rutin, presented a higher negative chronotropic effect, similar to propranolol. CONCLUSION: Oral administration of aqueous extract of Artocarpus artilis has cardio-protective functions in myocardial injury, in part, by decreasing the HR, reduced contractility and infarct size. These findings may explain the cardio-protective use of A. altilis in traditional medicine.
Subject(s)
Artocarpus/chemistry , Cardiotonic Agents/pharmacology , Myocardial Infarction/prevention & control , Plant Extracts/pharmacology , Animals , Cardiotonic Agents/administration & dosage , Cardiotonic Agents/isolation & purification , Dose-Response Relationship, Drug , Herb-Drug Interactions , Isoproterenol/toxicity , Male , Myocardial Contraction/drug effects , Myocardium/pathology , Plant Extracts/administration & dosage , Plant Leaves , Rats , Rats, Sprague-DawleyABSTRACT
Quassinoids often exhibit antioxidant and antiproliferative activity. Emerging evidence suggests that these natural metabolites also display chemopreventive actions. In this study, we investigated the potential for the quassinoid glaucarubulone glucoside (Gg), isolated from the endemic Jamaican plant Castela macrophylla (Simaroubaceae), to display potent cytotoxicity and inhibit human cytochrome P450s (CYPs), particularly CYP1A enzymes, known to convert polyaromatic hydrocarbons into carcinogenic metabolites. Gg reduced the viability of MCF-7 breast adenocarcinoma cells (IC50 = 121 nm) to a greater extent than standard of care anticancer agents 5-fluorouracil, tamoxifen (IC50 >10 µm) and the tamoxifen metabolite 4-hydroxytamoxifen (IC50 = 2.6 µm), yet was not cytotoxic to non-tumorigenic MCF-10A breast epithelial cells. Additionally, Gg induced MCF-7 breast cancer cell death. Gg blocked increases in reactive oxygen species in MCF-10A cells mediated by the polyaromatic hydrocarbon benzo[a]pyrene (B[a]P) metabolite B[a]P 1,6-quinone, yet downregulated the expression of genes that promote antioxidant activity in MCF-7 cells. This implies that Gg exhibits antioxidant and cytoprotective actions in non-tumorigenic breast epithelial cells and pro-oxidant, cytotoxic actions in breast cancer cells. Furthermore, Gg inhibited the activities of human CYP1A according to non-competitive kinetics and attenuated the ability of B[a]P to induce CYP1A gene expression in MCF-7 cells. These data indicate that Gg selectively suppresses MCF-7 breast cancer cell growth without impacting non-tumorigenic breast epithelial cells and blocks B[a]P-mediated CYP1A induction. Taken together, our data provide a rationale for further investigations of Gg and similar plant isolates as potential agents to treat and prevent breast cancer. Copyright © 2017 John Wiley & Sons, Ltd.
Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Cytotoxins/therapeutic use , Glaucarubin/analogs & derivatives , Plant Extracts/therapeutic use , Simaroubaceae/chemistry , Antioxidants/therapeutic use , Cell Line, Tumor/drug effects , Cell Proliferation/drug effects , Cytochrome P-450 Enzyme System/drug effects , Female , Gene Expression/drug effects , Glaucarubin/therapeutic use , Humans , Jamaica , MCF-7 Cells/drug effects , Quassins/therapeutic useABSTRACT
The effect of apocynin on the activity of arylamine N-acetyltransferases (NATs) in excised liver samples was examined using eighteen Sprague-Dawley rats. Three groups of six animals each were fed a normal diet alone or a treatment of 50 or 100 mg/kg/day of apocynin via gavages for eight (8) weeks. Chronic in vivo administration of apocynin led to significant (p < 0.001) reduction of in vitro liver NAT activity up to 93% as compared with untreated rats (18.80 ± 2.10 µmols p-anisidine/min/µg liver protein). In vitro exposure of untreated liver homogenates to apocynin led to a dose-dependent inhibition of NAT activity with IC50 = 0.69 ± 0.02 mM. In silico modelling of apocynin tautomers and radical species into human NAT crystal structures supported the hypothesis that thiol functionalities in NAT enzymes may be crucial in apocynin binding. The involvement of human NAT enzymes in different pathological conditions, such as cancer, has encouraged the research for selective NAT inhibitors in both humans and animal models with possible chemopreventive properties.
Subject(s)
Acetophenones/chemistry , Antineoplastic Agents/chemistry , Arylamine N-Acetyltransferase/antagonists & inhibitors , Enzyme Inhibitors/chemistry , Acetophenones/metabolism , Administration, Oral , Amino Acid Sequence , Animals , Antineoplastic Agents/metabolism , Arylamine N-Acetyltransferase/chemistry , Arylamine N-Acetyltransferase/metabolism , Catalytic Domain , Complex Mixtures/chemistry , Enzyme Inhibitors/metabolism , Humans , Isoenzymes/antagonists & inhibitors , Isoenzymes/chemistry , Isoenzymes/metabolism , Kinetics , Liver/chemistry , Liver/drug effects , Liver/enzymology , Male , Mice , Molecular Docking Simulation , Protein Binding , Protein Interaction Domains and Motifs , Protein Structure, Secondary , Rats , Rats, Sprague-Dawley , Sequence Alignment , Sequence Homology, Amino AcidABSTRACT
INTRODUCTION: CYP, a ubiquitous superfamily of enzymes expressed in major organs in humans, plays a key role in biosynthesis of steroids and metabolism of xenobiotics. Inhibitors of these vital enzymes provide, as tools, the opportunity to gain an insight to their role in a myriad of bioactivity and to intervene as therapeutics in disease. AREAS COVERED: This article reviews granted patents for human CYP inhibitors from the US and European territories within the past decade. EXPERT OPINION: Granted patents, albeit mostly embodying evidence from in vitro and limited preclinical trials, demonstrate good potential for use in industry and the clinic following future human trials. Indeed, only a handful is on the market or under clinical evaluation. Diagnostic monoclonal antibodies (mAbs) show high specificity for CYP families 1, 2, and 3, while potent inhibitors of CYPs 17, 19, 24, 26, 3A4 activities, in use with or without other drugs, display potential in treating prostate and breast cancers, dermatology, and improved retroviral therapy, although some may have challenges in delivery to target tissues. The involvement of this superfamily of enzymes in cellular functions, a multitude of disease states, and pharmacogenetics make them ideal candidates to better understand contemporary human health issues and identification of targeted, specific, and potent inhibitors is a useful strategy to employ, toward achieving that wider goal.
Subject(s)
Cytochrome P-450 Enzyme Inhibitors/pharmacology , Drug Discovery , Patents as Topic , Cytochrome P-450 Enzyme Inhibitors/therapeutic use , HumansABSTRACT
The chemical investigation of specimens of the Jamaican brown alga Stypopodium zonale led to the isolation of a cytotoxic compound, zonaquinone acetate (1), along with known compounds flabellinone, not previously identified in S. zonale, stypoldione, 5',7'-dihydroxy-2'-pentadecylchromone and sargaol. The structures of the metabolites were established by analysis of the spectral data including 1D and 2D NMR experiments while the stereochemistry of 1 was assessed by VCD measurements. Cytotoxic activity was reported in vitro for 1 against breast cancer and colon cancer cell lines at IC(50) values of 19.22-21.62 µM and 17.11-18.35 µM respectively, comparing favorably with standard treatments tamoxifen (17.22-17.32 µM) and fluorouracil (27.03-31.48 µM). When tested with liver cancer cells (Hep G2), no activity was observed. Weak antioxidant activity was observed with 1 but sargaol exhibited high activity.
Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Phaeophyceae/chemistry , Cell Line, Tumor , Diterpenes/chemistry , Diterpenes/pharmacology , Humans , Terpenes/chemistry , Terpenes/pharmacologyABSTRACT
CONTEXT AND OBJECTIVES: Artocarpus altilis (Parkinson) Fosberg (Moraceae) (breadfruit) leaves are used as an antihypertensive remedy. We investigated the possible mechanisms of action of its aqueous extract and its effect on cytochromes P450 (CYP) enzyme activities. MATERIALS AND METHODS: Intravenous administration of an aqueous leaf extract (20.88-146.18 mg/kg) of A. altilis on mean arterial pressure and heart rate were recorded via cannulation of the carotid artery on anaesthetized normotensive Sprague-Dawley rats. Recordings of the contractile activity of the aortic rings to the extract (0.71-4.26 mg/mL) were studied using standard organ bath techniques. Inhibitions of human CYP3A4 and CYP2D6 enzyme activities were evaluated by means of a fluorometric assay in 96 well plates using heterologously expressed microsomes. RESULTS: A. altilis caused significant (p < 0.05) hypotensive and bradycardiac responses unaffected by atropine (2 mg/kg) and mepyramine (5 mg/kg), but attenuated by propranolol (1 mg/kg) and N(G)-nitro-L-arginine methyl ester (5 mg/kg). The extract (0.71-4.26 mg/mL) significantly (p < 0.05) relaxed phenylephrine (10â»9-10â»4 M) and 80 mM KCl-induced contractions in endothelium intact and denuded aortic rings; and caused a significant (p < 0.05) rightward shift of the Ca²âº dose-response curves in Ca²âº-free Kreb's solution. Moderate inhibitions of cytochrome P450s (CYP3A4 and CYP2D6) enzyme activities with IC50 values of 0.695 ± 0.187 and 0.512 ± 0.131 mg/mL, respectively, were produced. CONCLUSION: A. altilis exhibits negative chronotropic and hypotensive effects through α-adrenoceptor and Ca²âº channel antagonism. Drug adversity effects are unlikely if the aqueous leaf extract is consumed with other medications reliant on CYP3A4 and CYP2D6 metabolism. This study thus provides scientific evidence for the use of the breadfruit in the treatment of hypertension.
Subject(s)
Adrenergic alpha-Antagonists/pharmacology , Antihypertensive Agents/pharmacology , Artocarpus/chemistry , Calcium Channel Blockers/pharmacology , Muscle, Smooth, Vascular/drug effects , Plant Extracts/pharmacology , Plant Leaves/chemistry , Adrenergic alpha-Antagonists/administration & dosage , Animals , Antihypertensive Agents/administration & dosage , Aorta, Thoracic/drug effects , Aorta, Thoracic/metabolism , Aryl Hydrocarbon Hydroxylases/antagonists & inhibitors , Aryl Hydrocarbon Hydroxylases/genetics , Aryl Hydrocarbon Hydroxylases/metabolism , Calcium Channel Blockers/administration & dosage , Cytochrome P-450 CYP2D6/genetics , Cytochrome P-450 CYP2D6/metabolism , Cytochrome P-450 CYP2D6 Inhibitors , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/pharmacology , Ethnopharmacology , Humans , In Vitro Techniques , Jamaica , Male , Muscle, Smooth, Vascular/metabolism , Plant Extracts/administration & dosage , Rats , Rats, Sprague-Dawley , Recombinant Proteins/antagonists & inhibitors , Recombinant Proteins/metabolism , Vasodilator Agents/administration & dosage , Vasodilator Agents/pharmacologyABSTRACT
BACKGROUND: Extracts from the marine algae Cymopolia barbata have previously shown promising pharmacological activity including antifungal, antitumor, antimicrobial, and antimutagenic properties. Even though extracts have demonstrated such bioactivity, isolated ingredients responsible for such bioactivity remain unspecified. In this study, we describe chemical characterization and evaluations of biological activity of prenylated bromohydroquinones (PBQ) isolated from the marine algae C. barbata for their cytotoxic and chemopreventive potential. METHODS: The impact of PBQs on the viability of cell lines (MCF-7, HT29, HepG, and CCD18 Co) was evaluated using the MTS assay. In addition, their inhibitory impact on the activities of heterologously expressed cytochrome P450 (CYP) enzymes (CYP1A1, CYP1A2, CYP1B1, CYP2C19, CYP2D6, and CYP3A4) was evaluated using a fluorescent assay. RESULTS: 7-Hydroxycymopochromanone (PBQ1) and 7-hydroxycymopolone (PBQ2) were isolated using liquid and column chromatography, identified using 1 H and 13 C NMR spectra and compared with the spectra of previously isolated PBQs. PBQ2 selectively impacted the viability of HT29, colon cancer cells with similar potency to the known chemotherapeutic drug, fluorouracil (IC50, 19.82 ± 0.46 µM compared to 23.50 ± 1.12 µM, respectively) with impact toward normal colon cells also being comparable (55.65 ± 3.28 compared to 55.51 ± 3.71 µM, respectively), while PBQ1 had no impact on these cells. Both PBQs had potent inhibition against the activities of CYP1A1 and CYP1B1, the latter which is known to be a universal marker for cancer and a target for drug discovery. Inhibitors of CYP1 enzymes by virtue of the prevention of activation of carcinogens such as benzo-a-pyrene have drawn attention as potential chemopreventors. PBQ2 potently inhibited the activity of CYP1B1 (IC50 0.14 ± 0.04 µM), while both PBQ1 and PBQ2 potently inhibited the activity of CYP1A1 (IC50s of 0.39 ± 0.05 µM and 0.93 ± 0.26 µM, respectively). Further characterizations showed partial noncompetitive enzyme kinetics for PBQ2 with CYP1B1 with a Ki of 4.7 × 10-3 ± 5.1 × 10-4 µM and uncompetitive kinetics with CYP1A1 (Ki = 0.84 ± 0.07 µM); while PBQ1 displayed partial non competitive enzyme kinetics with CYP1A1 (Ki of 3.07 ± 0.69 µM), noncompetitive kinetics with CYP1A2 (Ki = 9.16 ± 4.68 µM) and uncompetitive kinetics with CYP1B1 (Ki = 0.26 ± 0.03 µM) . CONCLUSIONS: We report for the first time, two isolated ingredients from C. barbata, PBQ1 and PBQ2, that show potential as valuable chemotherapeutic compounds. A hydroxyl moiety resident in PBQ2 appears to be critical for selectivity and potency against the cancer colon cells, HT29, in comparison to the three other malignant cell lines studied. PBQs also show potency against the activities of CYP1 enzyme which may be a lead in chemoprevention. This study, the first on isolates from these marine algae, exemplifies the value of searching within nature for unique structural motifs that can display multiple biological activities.
ABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: The work described in this paper aimed to study the prevalence of herbal medicine use in treating illness and concomitant use with pharmaceutical medicines in Jamaica. MATERIALS AND METHODS: A survey using a structured questionnaire was administered by a trained interviewer to randomly selected adults in systematically selected households within randomly selected urban and rural clusters. Categorical data analysis was performed using Stata version 10 software. RESULTS: 91.4%(372/407) of selected people agreed to participate. 72.6%(270/372) self-medicated with herbs within the previous year. Commonly treated were illnesses of the respiratory system (RS, 77.8%(210/270)), gastro-intestinal tract (GIT, 53.3%(144/270)) and health maintenance using tonics (29.6%(80/270)). 26.7%(72/270) of respondents used pharmaceuticals concomitantly with medicinal plants. Commonly treated were illnesses of the RS (20.4%(55/270)), GIT (13.7%(37/270)) and hypertension (10.0%(27/270)). 19.4% (14/72) of physicians knew of such practices. There was significant association of herb use with/without drugs with age (p<0.001), employment status (p<0.001), religion (p=0.004), gender (p=0.02) and educational level (p=0.031). Thus prevalence of herb use alone was greatest amongst people aged 35-44 and 45-54 years; those employed; Rastafarians; those without health insurance; males and people who had completed secondary education. Whilst prevalence of concomitant herb-drug use was greater amongst people aged 65 years and older; those retired; those of religions other than Rastafarians and Christians, females and people who had attained primary education and below. CONCLUSIONS: Self-medication with herbs in Jamaica is highly prevalent and highest for self-limiting conditions of the RS, GIT and health maintenance with tonics. Concomitant herb and drug use is highest for self-limiting conditions of the RS, GIT and hypertension, and the use of combined therapy highlights the need for investigations on potential drug-herb interactions. Physicians have limited awareness and knowledge of such concomitant usage, further highlighting the need for increased dialogue with patients, knowledge of medicinal plants and their uses and a heightened pharmacovigilance to avoid adversities that may arise from potential drug-herb interactions.
Subject(s)
Health Behavior , Health Knowledge, Attitudes, Practice , Medicine, Traditional/statistics & numerical data , Pharmaceutical Preparations , Plant Preparations/therapeutic use , Adolescent , Adult , Age Factors , Aged , Awareness , Communication , Cultural Characteristics , Drug-Related Side Effects and Adverse Reactions , Educational Status , Employment , Female , Health Behavior/ethnology , Health Care Surveys , Health Knowledge, Attitudes, Practice/ethnology , Herb-Drug Interactions , Humans , Jamaica , Male , Middle Aged , Physician-Patient Relations , Plant Preparations/adverse effects , Plants, Medicinal , Religion and Medicine , Self Medication , Surveys and Questionnaires , Young AdultABSTRACT
UNLABELLED: Due to the global rise in the popularity of herbal medicines, adversities resulting from concomitant use of both prescription drugs and herbs are becoming an increasingly important public health issue. OBJECTIVES: To estimate the prevalence of the use of herbal medicines among persons on prescription medicines in Jamaica. Findings are thought to aid in estimates of the risk of adversities from drug-herb interactions through laboratory investigations and to provide awareness among policy makers responsible for the design of appropriate pharmacovigilance systems in the country. METHODS: A survey was conducted in eighteen pharmacies throughout Jamaica and patients or parents/carers of children who were on at least one prescription medicine were administered a structured questionnaire by trained interviewers. RESULTS: Of 399 persons invited to participate in the study 365 (91.5% response rate) agreed to do so and were included in the study. This study population consisted of 306 adults and 60 children and of that 243 adults (80.6%) and 45 children (75.6%) engaged in the concomitant use of herbs and drugs. Patients with a variety of disease conditions, in both rural and urban environs engaged in concomitant herb-drug use. Persons with higher salary (P<0.1) and those with health insurance (P<0.02) tended to have a lower prevalence of herb-drug concomitant use. Among persons indicating such practices the most commonly cited reason for concurrent use of prescription medicine and herbal preparations was the belief that there was no harm in taking both (269, 94.0%) followed by the belief that the prescription medicine alone was not adequate cure (211, 71%). Only 55 (18%) respondents who practised such co-medication indicated that their doctors knew of their use of herbal preparations. CONCLUSION: There is a high prevalence of herb-drug concomitant use in Jamaica, and an awareness within the medical community and those monitoring adversities would serve well to mitigate risks from potential drug-herb interactions.