Pharmacological and Toxicological Study of a Traditional Mayan Herbal Preparation Used as Antihypertensive Agent

Aims: To evaluate preparation herbal mixed of Pouteria campechiana, Chrysophyllum cainito, Citrus limonum and Annona muricata (PCCA) on vasorelaxant and hypotensive effect on rat model and toxicological data after acute oral administration to give scientific support to the use ethnomedical and to explore their potential damaging on oral intake. Study Design: Experimental. Place and Duration of Study: Sample female and male Wistar rats. Pharmacology laboratory of Chemistry School and Department of Clinical and Epidemiological Research of Medicine School, Autonomous University of Yucatán. Between October 2014 and July 2016. Methodology: An ethanolic extract of PCCA was prepared at a ratio of 1:1:1:1 of each plant plus individual extracts were prepared. Vasorelaxant effect was assessed (3.03 to 100 μg/mL), hypotensive effect ((100, 200, 300 mg/Kg) and median lethal dose (LD50) by oral acute toxicity method (OECD 423 guide). Results: PCCA extract induced a significant vasorelaxation (medium effective concentration (EC50)=463.43 μg/mL) in a concentration-dependent manner in aorta’s endothelium-intact rings and this effect was partially endothelium-dependent. Acute oral administration of 200 and 300 mg/kg of PCCA exhibited significant decrease in systolic blood pressure in normotensive rats. PCCA did not show clinical toxicity of acute oral administration. Only 2000 mg/kg show histopathological inflammatory responses on gut and liver. Conclusion: PCCA induces a significant cardiovascular effect and was not toxic for rodents. The results support the popular use of some Mayan Medicinal plants as antihypertensive agents; however, clinical studies are necessary.

Antihyperglycemic effect and genotoxicity of Psittacanthus calyculatus extract in streptozotocin-induced diabetic rats / Efecto antihiperglicemico y genotoxico de extractos de Psittacanthus calyculatus en ratas diabeticas inducidas con streptozotocina

Psittacanthus calyculatus (DC.) G. Don (Lorantaceae) is known as “ingerto”. The aerial parts are used in the treatment of diabetes and hypertension. Methanolic extract was tested with streptozotocin-induced diabetic rats. Dose of 200 mg/Kg body weight for acute experiments, as well as 200 and 400 mg/Kg for semi-chronic bioassay were used. In both experiments extract produced significant hypoglycemic activity in streptozotocin-induced rats when compared with diabetic control (p 0.05). To study possible clastogenic effects of methanolic extract a mouse micronucleus test was performed (as part of the genetic toxicology trial). CD-1 white mice were administered with 200 and 400 mg/Kg of methanolic extract of P. calyculatus dissolved in water by intraperitoneal injection. The cytotoxic activity polychromatic erythrocytes/normochromatic erythrocytes (PCE/NCE) and the induction of micronuclei in peripheral blood erythrocytes (MNPCE) was recorded with sampling times of 24, 48 and 72, h after an exposure without killing of mice. The frequency of MNPCE in the circulating blood obtained from the tail of the mouse was statistically not significant compared with its negative control animals (time zero) and the PCE/NCE ratio showed evidences of light cytotoxic activity compared with its negative control animals (time zero). Thus, in this test, the methanolic extract of Psittacanthus calyculatus dissolved in water did not induce chromosomal damage resulting in micronucleus formation in peripheral blood erythrocytes and showed light cytotoxic activity.

En la zona del bajío mexicano la planta Psittacanthus calyculatus (DC.) G. Don (Lorantaceae) es conocida popularmente como “ingerto”. Las partes aéreas de este vegetal se utilizan para tratar enfermedades como la diabetes y la hipertensión. Se realizaron experimentos agudos y semi-crónicos en ratas diabéticas inducidas con estreptozotocina. El efecto hipoglucemiante del extracto metanólico se evaluó a dosis de 200 y 400 mg/Kg de peso. En ambos experimentos, el extracto redujo significativamente (p < 0.05) la glucemia en las ratas diabéticas. Para determinar los posibles efectos clastogénicos del extracto metanólico se administraron por vía intraperitoneal a ratones cepa CD-1 las dosis que mostraron actividad hipoglucemiante disueltas en agua y se llevó a cabo el bioensayo de micronúcleos en sangre periférica de ratón. La actividad citotóxica se determinó mediante el cálculo de la relación entre los eritrocitos policromáticos y los eritrocitos normocromáticos (PCE/NCE). La inducción de micronúcleos en eritrocitos de sangre periférica (MNPCE) fue el indicador de gentotoxicidad los cuales se midieron a las 24, 48 y 72 horas después de la administración del extracto. La frecuencia de micronúcleos en eritrocitos policromáticos no fue estadísticamente significativa con relación al control negativo (al tiempo 0) por lo tanto, el extracto no induce daño cromosómico. Asimismo la relación PCE/NCE mostró que el extracto metanólico fue ligeramente citotóxico a la dosis de 400 mg/Kg y a las 48 h posteriores a la administración.