Pharmacological study of Stachytarpheta cayennensis Vahl in rodents.

Freeze-dried aqueous extracts (AEs, 0.1-1g/kg body wt., p.o.) obtained from entire or selected parts of Stachytarpheta cayennensis were tested for their effects on gastric secretion, gastric motility, inflammation and pain in rodents, with the purpose of validating the plant's ethnomedical uses. The AE-Total, AE-Flowers and AE-Leaves but not AE-Stems inhibited the gastric acid secretion in pylorus-ligated rats with varying potency. Purification of AEs yielded the semipurifed fractions EtFs rich in iridoids. All the EtFs with exception of EtF-Stems inhibited gastric acid secretion of pylorus ligated mice. While AE-Total stimulated the intestinal transit of mice by 43%, AE-Leaves delayed it by 38%. These effects on intestinal transit were not observed when the EtFs were tested. Only AE-Leaves and AE-Flowers altered the gastric emptying of semisolids, increasing it by 45% and 69%, respectively. These results indicate that the compounds related to inhibition of gastric acid secretion and gastrointestinal motility are different. The AE-Total reduced abdominal writhing induced by acetic acid potently (ED50 value = 700 mg/kg, p. o.) without altering the writhes induced by acetylcholine. Attempts to identify the mechanism of analgesia were unsuccessful since the AE-Total did not show analgesic effects when tested in different models of pain such as formalin and capsaicin or the tail-flick test. Pretreatment of animals with AE-Total did not show antiinflammatory activity in any of the acute (paw edema induced by carrageenin, dextran or histamine, pleurisy induced by carrageenin and capsaicin-induced mouse ear edema) or chronic (air pouch) models used. No toxic signs were observed after administration of the different extracts up to 2 g/kg body wt., p.o. Collectively, the results confirmed folk information indicating presence of analgesic, mild laxative and potent inhibition of gastric secretion activities in the aqueous extracts of S. cayennensis. The results do not, however confirm the folk use of the plant as an antiinflammatory medicine.

Solanum paniculatum L. (Jurubeba): potent inhibitor of gastric acid secretion in mice.

Solanum paniculatum L. is used commonly in Brazilian folk medicine for the treatment of liver and gastrointestinal disorders. The freeze-dried aqueous extracts (WEs) obtained from distinct parts of the plant (flowers, fruits, leaves, stems and roots) were tested to determine their antiulcer and antisecretory gastric acid activities using mice. The aqueous extracts of roots, stems and flowers inhibited gastric acid secretion in pylorus-ligated mice with ED50 values of 418, 777 and 820 mg/kg body wt. (i.d.), respectively. Extracts of leaves (0.5-2 g/kg body wt., i.d.) did not affect gastric secretion, whereas fruit extracts (0.5-2 g/kg body wt., i.d.) stimulated gastric acid secretion. The stimulatory effect of the fruit extract was inhibited by pretreatment with atropine (5 mg/kg body wt., i.m.) but not with ranitidine (80 mg/kg body wt., i.p.) suggesting that the fruit extract activates the muscarinic pathway of gastric acid secretion. In contrast, administration of the root extract into the duodenal lumen inhibited histamine- and bethanechol-induced gastric secretion in pylorus-ligated mice. In addition, the aqueous extract of roots (ED50 value, 1.2 g/kg body wt., p.o.) protected the animals against production of gastric lesions subsequent to the hypersecretion induced in mice by stress following cold restraint. This effect was not reproduced when the lesions were induced by blockade of prostaglandins synthesis via subcutaneous injection of indomethacin. Thus, antiulcer activity of the plant extracts appears to be related directly to a potent anti-secretory activity. No toxic signs were observed following administration of different extracts up to 2 g/kg body wt., p.o. Collectively, the results validate folk use of Solanum paniculatum L. plant to treat gastric disorders.

Obesity, diabetes, hypertension, and tobacco consumption in an urban adult Mexican population.

BACKGROUND: The aim of this study was to describe the prevalence of some of the main coronary risk factors in an open Mexican adult population. METHODS: This is a cross-sectional study that includes individuals from eight different cities. Except for Mexico City, all centers were located in medium-sized cities ranging from 1 to 5 million inhabitants. Eligible subjects were adults 20 years of age or older. Exclusion criteria included subjects seeking medical attention due to an acute illness or individuals unable to provide the requested information or written consent to participate in the study. Men (n = 567) and women (n = 1,018) were included. A previously validated interview was conducted. A questionnaire assessed demographic and lifestyle factors. Capillary glucose concentration and blood pressure were obtained. Remarkably, 40% of the population had a body mass index (BMI) between 25 and 29.9 kg/m(2); an additional 28% had a BMI >30 kg/m(2). A large proportion of the individuals had abdominal fat distribution (62% of men and 81% of women). At the time of the evaluation, 30% of men and 18% of women were regular smokers. RESULTS: Blood pressure >140/90 mmHg was found in 29.4% of the population. Less than one half of the subjects had a previous measurement of plasma cholesterol (47%) or triglycerides (42%). The prevalence of diabetes was 9.02%. A significant percentage of these subjects were <40 years of age (18.8% of the diabetic population). CONCLUSIONS: The prevalence of obesity, diabetes, and hypertension in the population reported here is among the highest reported in Mexican populations.

Natural products isolated from Mexican medicinal plants: novel inhibitors of sulfotransferases, SULT1A1 and SULT2A1.

Calophyllum brasiliense, Lonchocarpus oaxacensis, and Lonchocarpus guatemalensis are used in Latin American folk medicine. Four natural xanthones, an acetylated derivative, and two coumarins were obtained from C. brasiliense. Two flavanones were extracted from L. oaxacensis and one chalcone from L guatemalensis. These compounds were tested as substrates and inhibitors for two recombinant sulfotransferases (SULTs) involved in the metabolism of many endogenous compounds and foreign chemicals. Assays were performed using recombinant phenolsulfotransferase (SULT1A1) and hydroxysteroidsulfotransferase (SULT2A1). Three of the five xanthones, one of the flavonoids and the coumarins tested were substrates for SULT1A1. None of the xanthones or the flavonoids were sulfonated by SULT2A1, whereas the coumarin mammea A/BA was a substrate for this enzyme. The natural xanthones reversibly inhibited SULT1A1 with IC50 values ranging from 1.6 to 7 microM whereas much higher amounts of these compounds were required to inhibit SULT2A1 (IC50 values of 26-204 microM). The flavonoids inhibited SULT1A1 with IC50 values ranging from 9.5 to 101 microM, which compared with amounts needed to inhibit SULT2A1 (IC50 values of 11 to 101 microM). Both coumarins inhibited SULT1A1 with IC50 values of 47 and 185 pM, and SULT2A1 with IC50 values of 16 and 31 microM. The acetylated xanthone did not inhibit either SULT1AI or SULT2A1 activity. Rotenone from a commercial source had potency comparable to that of the flavonoids isolated from Lonchocarpus for inhibiting both SULTs. The potency of this inhibition depends on the position and number of hydroxyls. The results indicate that SULT1A1, but not SULT2A1, is highly sensitive to inhibition by xanthones. Conversely, SULT2A1 is 3-6 times more sensitive to coumarins than SULT1A1. The flavonoids are non-specific inhibitors of the two SULTs. Collectively, the results suggest that these types of natural products have the potential for important pharmacological and toxicological interactions at the level of phase-II metabolism via sulfotransferases.

Inhibition of gastric acid secretion by the aqueous extract and purified extracts of Stachytarpheta cayennensis.

Stachytarpheta cayennensis Schauer (Verbenaceae) is used in folk medicine to treat gastric and intestinal disturbances. The freeze-dried aqueous extract of the whole plant tested to rodents up to the dose of 2 g kg-1, p.o., did not produce signs of toxicity. The extract (0.5-2 g kg-1, p.o.) increased the intestinal motility and protected mice against ulcers induced by restraintin-cold, ethanol or indomethacin. Injected into the duodenal lumen the extract inhibited the basal acid secretion as well as that induced by histamine and bethanecol in pylorus-ligated mice. Partition of the aqueous extract in organic solvents yielded semipurified fractions whose antiacid activity guided further chemical purification. All the fractions were chromatographically characterized, the main substances in the active extract being flavonoids and amines; some substances were revealed only under UV light. The most purified active fraction obtained presented a specific activity 5-10 times higher than that detected in the original extract. Data from pharmacological studies indicate that the antiulcer activity of S. cayennensis is related to a specific inhibition of gastric acid secretion. Cholinergic and histaminergic stimulation of acid secretion were similarly reduced by the extracts suggesting inhibition of common steps in both pathways, possibly at the level of histamine release/H2 receptor interaction, or at the proton pump. Whatever the mechanisms involved, the present data confirm the plant effectiveness as antiacid/antiulcer and laxative.

Regímenes antibióticos en la prevención de sepsis de herida postapendicectomía / Antibiotic regimens in sepsis prevention of post-appendectomy wound

Se llevó a cabo un estudio prospectivo al azar de 318 casos consecutivos con apendicitis para dilucidar la eficacia y eficiencia de los regímenes profilácticos Gentamicina/Clindamicina (G/C), Penicilina/Cloranfenicol (PC) y Gentamicina/Metronidazol (G/M), en prevenir la sepsis de herida postapendicectomía. Hubo 3% de sepsis de herida en toda la muestra. 47 casos con heridas limpias contaminadas por apendicitis catarral recibieron sólo una dosis preoperatória y no hubo ningún caso de sepsis de herida. 173 casos, con heridas contaminadas por apendicitis supurada recibieron 24 horas de profilaxis y la sepsis de herida ocurrió en el 4% en cada uno de los grupos G/C y P/C. 98 pacientes con heridas sucias apendicitis gangrenada o perforada recibieron profilaxis por 72 horas y la sepsis de la herida ocurrió en el 5%, 6% y 5% en los grupos G/C, P/C y G/M respectivamente. Los antimicrobianos se administraron endovenosamente excepto el Metronidazol que se usó por vía oral y rectal. Concluimos que los regímenes C/G, P/C y G/M, son eficaces en la prevención de sepsis de herida postapendicectomía sin diferencias significativas (P > 0.40) y que el régimen Gentamicina/Metronidazol es el más eficiente