An ethnobotanical survey of medicinal plants in Trinidad.

BACKGROUND: An ethnobotanical survey was conducted on the Caribbean island of Trinidad to identify medicinal plants commonly used in traditional medicine to treat a variety of medical conditions. METHODS: A pilot survey was conducted to identify the top ten most common ailments where medicinal plants were used. The results of the foregoing study guided a wider national survey conducted between October 2007 and July 2008. A total of 450 households from 50 rural communities were interviewed using the TRAMIL (Traditional Medicine in the Islands) questionnaire for data collection. Details of plants, part(s) used, and remedy formulations were elicited from informants and voucher specimens collected for identification at the National Herbarium of Trinidad and Tobago. The TRAMIL methodology set a limit of a plant with 20 % or more citations for any particular ailment as having significant or popular use. RESULTS: At the end of the survey 917 single plant remedies were identified. The majority of species were from the following families; Asteraceae, Lamiaceae, Leguminosae, Verbenaceae and Poaceae. Applying the TRAMIL 20 % citation of a plant for popular use as significant, Leonotis nepetifolia (for cough/common cold), Gomphrena globosa (for "stoppage-of-water"), Curcuma longa and Senna occidentalis (for "afterbirth"), Cymbopogon citratus and Neurolaena lobata (for fever), and Citrus limon (for kidney stones) qualified in our study. Those not reaching the TRAMIL 20 % significant (popular) use were Stachytarpheta jamaicensis (L.) Vahl, Senna alata (L.) Roxb.and Momordica charantia L. which were widely used as "'cooling/cleanser'" in our survey. CONCLUSIONS: Our survey showed significant retention of traditional knowledge of medicinal plants in rural Trinidad. More interestingly, a large remnant of medico-cultural concepts such as "cooling/cleanser", "afterbirth", "stoppage-of-water" and "womb infection" persist in the rural population. Although the scientific literature show that some of the cited plants possessed antimicrobial, anti-inflammatory and related pharmacological activities in laboratory studies, these results must be taken with caution until clinical trials are conducted to establish safety and efficacy.

Drug prescribing for hypertension at primary healthcare facilities in Trinidad.

OBJECTIVE: To describe the drug prescribing pattern for hypertension at primary healthcare facilities throughout Trinidad. METHODS: A descriptive, cross-sectional survey was conducted at 22 primary healthcare facilities across Trinidad using a de novo, pilot-tested questionnaire during June to August 2006. RESULTS: A total of 547 hypertensive patients were recruited into the study. There was a high prevalence of diabetes mellitus (57.6%). Information on the current drug prescribed was available for 442 patients (80.0%) and 26 of these patients (6.1%) were managed without drug intervention. On average, patients were prescribed 1.47 antihypertensive drugs. Angiotensin converting enzyme (ACE) inhibitors, particularly enalapril, were the most commonly prescribed class of antihypertensive drugs in 63.6% of patients. beta-blockers, thiazide diuretics and calcium channel blockers were prescribed in 29.2%, 25.8% and 12.0% of patients respectively. CONCLUSIONS: There was significant use of ACE inhibitors, beta-blockers, thiazide diuretics and calcium channel blockers. Angiotensin converting enzyme inhibitors (as monotherapy or in combination with other drug classes) were more likely to be prescribed in diabetic hypertensive patients. Thiazide diuretics were not used as frequently as expected given the evidence which demonstrate similar efficacy with other classes of drugs and associated cost-saving. The observed prescribing pattern in the Trinidad public healthcare setting seems to point to an attempt to conform to recognized international and regional guidelines for the management of hypertension.

Cytotoxic activity of selected West Indian medicinal plants against a human leukaemia cell line.

OBJECTIVE: To assess the cytotoxic activities of crude extracts and solvent fractions of Spermacoce verticillata, Ficus pumila and Flemingia strobilifera against a MT-4 human leukaemia cancer cell line. METHODS: Crude extracts of dried leaves of S verticillata, F pumila and F strobilifera were made by exhaustive methanol extraction, fractions were obtained from sequential extraction of the crude extract using solvents of increasing polarity. Dose responses corresponding to cell survival following 72-hour exposure to the extracts were determined using a leukaemia cancer cell line (MT-4). Cell viability was assessed using the MTT[3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide] assay reading absorbances at 570 nm. Comparisons were made with controls and cell survival, in each sample well, was determined based on the ratio of the absorbance of the sample to the control. RESULTS: Crude extracts of S verticillata, F pumila and F strobilifera displayed cytotoxicity and the IC50 values were 89 microg/ml, 131 microg/ml and 81 microg/ml, respectively. The petroleum ether and chloroform fractions of the crude extracts of S verticillata and F strobilifera showed potent cytotoxic activity but the highest cytotoxic activity was found in the chloroform and butanol fractions of F pumila with IC50 values of 23 microg/ml and 26 microg/ml, respectively. CONCLUSION: The crude extracts of S verticillata, F pumila and F strobilifera were shown to be cytotoxic to the leukaemia cell line, MT-4 and IC50 values were determined. Fractionation of the crude extracts by solvent-solvent extraction enabled determination of the active fractions and their IC50 values. We propose that cytotoxic activity may be due to antioxidant compounds previously isolated from these plants.

Factors affecting the pharmacokinetics of herbal preparations and their impact on the outcome of clinical trials

This paper summarizes research on the pharmacokinetic characteristics of popular herbal medicines (such as Hypericum perforatum, Echinacea, Camellia sinensis, Tanacetum parthenium and Ginkgo biloba) in human studies, and in in vitro and in vivo systems. The effects of extract formulation, dosing frequency and biotransformation on the absorption and bioavailability of herbal drugs are briefly discussed.

A study design to evaluate folkloric medicinal plants in a mouse model for allergic asthma

Asthma is a chronic inflammatory respiratory disease with increasing incidence worldwide. Acute attacks account for 10 percent of admissions to the a Port-of-Spain General Hospital's A&E Department in Trinidad. In Barbados the incidence in children is between 12 and 16 percent. The Global Initiative for Asthma (GINA) guidelines recommend the use of inhaled corticosteroids and beta-blockers for disease management. We have found high levels of noncompliance (40 percent) at the major chest clinic in Trinidad due to unavailability of inhalers at the clinic's pharmacy and high cost at private pharmacies. A recent report in Trinidad showed a high prevalence of usage of medicinal herbs (86 percent) for chronic diseases in a surgical outpatient group. Such data support the imperative to determine the efficacy of these plants. Numerous medicinal plants have folkloric use in the treatment of asthma and wheezing. We have chosen a few local species including Eclipta alba (L.) Hassk, Cecropia peltata (L.), Eryngium foetidum (L.), Lippia alba (N.E. Brown) and Sambucus simpsonii (Rehder) to determine their pharmacological efficacy in reducing respiratory inflammation in a mouse model for allergic asthma

The need to monitor the usage of traditional herbal remedies

In the Caribbean, remedies made from Chenopodium ambrosioides are commonly used internally to treat many medical conditions such as: asthma, dysentry, fatigue and worms. The bioactive component found in the oil of this plant is ascaridole, which causes severe gastro-intestinal discomfort if used excessively. Other hazardous plants include Datura stramonium and Abrus precatorius. It is, therefore, imperative for awareness programs to be set up to educate the population about the use of herbal remedies. Assistance from the Chemistry, Food and Drugs Division of the Ministry of Health in Trinidad and Tobago is needed to formulate guidelines for the proper use of of herbal remedies by patients. A database of tropical poisonous herbs should be made available to hospitals and other health facilities around the country. It is imperative for physicians to ask about their use of herbal supplements and remedies as they are ideally situated to give good counseling and to even help in integrating herbal modalities into conventional care

Comparison of innovator and generic salbutamol inhalers: a double-blind randomized study of efficacy and tolerance.

Preliminary feedback from physicians and pharmacists in Trinidad suggests that generic pressurized metered dose inhalers (pMDIs) of salbutamol are not as effective as Ventolin and that they have poor patient acceptance. This study was designed to compare the clinical efficacy and tolerance of two generic inhalers available in Trinidad (Asthalin and Salomol) with Ventolin in stable asthmatics. Twenty-one physician-diagnosed stable asthmatics were administered the inhalers in a Latin-square randomized double-blind study with 80% power to identify differences in forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC) and peak expiratory flow rate (PEFR) before and 0.25, 0.5, 1, 2 and 3 h after inhalation. Pulse and blood pressure were recorded at similar time points. Seventeen patients completed the study. Within 15 min basal respiratory function significantly increased following inhalation from all three inhalers with a gradual decline over the observation period. Asthalin produced the highest changes in FEV1, PEFR and the longest duration of effect (p < 0.001). Respiratory function tests did not differ between Ventolin and Salomol. Pulse was not affected by treatments and mean arterial blood pressure fell after Asthalin. Ventolin was not superior to the generic pMDIs in improving pulmonary function. Fifteen patents reported cough sensation after Asthalin. Throat irritation and cough sensation after inhaling Asthalin may negate patient compliance. We suggest that optimizing particle size and cascade impact in the Asthalin inhaler may improve patient tolerance and acceptance with enhanced treatment outcome with cost-efficacy.

Hepatocellular response to chemical stress in CD-1 mice: induction of early genes and gamma-glutamylcysteine synthetase.

Exposure of cells to toxic chemical species can result in reduced glutathione (GSH) depletion, generation of free radicals, and/or binding to critical cell determinants. Chemical stress is usually followed by a concerted cellular response aimed at restoring homeostasis, although the precise initial stimulus for the response is unclear. We have focused on one component of this stress response, the up-regulation of gamma-glutamylcysteine synthetase (gamma-GCS) and the preceding molecular events involved in its regulation in an in vivo mouse model. Male CD-1 mice received buthionine sulphoximine (BSO; 7.2 mmol/kg), diethyl maleate (DEM; 4.2 mmol/kg), paracetamol (APAP; 3.5 and 1.0 mmol/kg), or carbon tetrachloride (CCl(4); 1.0 and 0.2 mmol/kg). Biochemical (serum transaminase and hepatic GSH levels) and molecular (c-jun and c-fos messenger RNA [mRNA] levels and activator protein 1 [AP-1] DNA binding activity) parameters were measured, as well as the consequent effects on gamma-GCS levels and activity. All compounds produced GSH depletion, but only the higher doses of APAP and CCl(4) caused liver damage. DEM, APAP, and CCl(4) increased c-jun and c-fos mRNA levels, together with an increase in AP-1 binding; BSO failed to induce AP-1 despite an increase in c-fos. Interestingly, the effects on gamma-GCS varied markedly according to the compound: BSO and DEM increased gamma-GCS enzyme activity, although only DEM, but not BSO, resulted in an increase in gamma-GCS(h) mRNA and protein. In contrast, APAP and CCl(4) both increased gamma-GCS(h) mRNA and protein; however, there was a marked dose-dependent decrease in gamma-GCS activity. These data indicate that the effect of chemical stress on the liver is compound specific and is not merely dependent on depletion of GSH.

Silent cholinesterase gene in an Asian Indian family in Trinidad.

Cholinesterase activity was estimated in the serum of a Trinidadian female of Asian Indian descent. Her serum cholinesterase was pathologically low (0.17 U/ml) compared to the average reported for the population (10.59 ± 2.77 U/ml), and her dibucaine number could not be estimated. In a pedigree study her sister displayed similar enzyme activity and cholinesterase was 0.09 U/ml. Cholinesterase could not be detected in the sera of both sisters using electrophoresis. Among three generations of the family studied, the silent variant of the cholinesterase gene could be segregated in offspring of the maternal uncle (normal cholinesterase phenotype) whose spouse's serum displayed an intermediate dibucaine number. The possible inheritance of the silent gene in the pedigree is discussed.

A study design to evaluate folkloric medicinal plants in a mouse model for allergic asthma

Asthma is a chronic inflammatory respiratory disease with increasing incidence worldwide. Acute attacks account for 10 percent of admissions to the a Port-of-Spain General Hospital's A&E Department in Trinidad. In Barbados the incidence in children is between 12 and 16 percent. The Global Initiative for Asthma (GINA) guidelines recommend the use of inhaled corticosteroids and beta-blockers for disease management. We have found high levels of noncompliance (40 percent) at the major chest clinic in Trinidad due to unavailability of inhalers at the clinic's pharmacy and high cost at private pharmacies. A recent report in Trinidad showed a high prevalence of usage of medicinal herbs (86 percent) for chronic diseases in a surgical outpatient group. Such data support the imperative to determine the efficacy of these plants. Numerous medicinal plants have folkloric use in the treatment of asthma and wheezing. We have chosen a few local species including Eclipta alba (L.) Hassk, Cecropia peltata (L.), Eryngium foetidum (L.), Lippia alba (N.E. Brown) and Sambucus simpsonii (Rehder) to determine their pharmacological efficacy in reducing respiratory inflammation in a mouse model for allergic asthma (AU)

The need to monitor the usage of traditional herbal remedies

In the Caribbean, remedies made from Chenopodium ambrosioides are commonly used internally to treat many medical conditions such as: asthma, dysentry, fatigue and worms. The bioactive component found in the oil of this plant is ascaridole, which causes severe gastro-intestinal discomfort if used excessively. Other hazardous plants include Datura stramonium and Abrus precatorius. It is, therefore, imperative for awareness programs to be set up to educate the population about the use of herbal remedies. Assistance from the Chemistry, Food and Drugs Division of the Ministry of Health in Trinidad and Tobago is needed to formulate guidelines for the proper use of of herbal remedies by patients. A database of tropical poisonous herbs should be made available to hospitals and other health facilities around the country. It is imperative for physicians to ask about their use of herbal supplements and remedies as they are ideally situated to give good counseling and to even help in integrating herbal modalities into conventional care (AU)