ABSTRACT Background: Diabetes mellitus treatment is based on oral hypoglycemic agents or insulin. Medicinal plants constitute an option, and the leaves of Prosopis ruscifolia (Pr) were shown to be effective in reducing glycemia in hyperglycemic animals. Objective: In this paper, we report the effect of P. rusciofolia (Pr) on insulin and incretin secretion in alloxan-induced hyperglycemic rats. Methodology: The effective dose was selected, and four groups (n=10) of Wistar rats were used. Two groups with normal glycemia received water or Pr (75 mg/Kg, per os, p.o.), and two groups with hyperglycemia induced by alloxan (intraperitoneal, ip), received water or Pr (75 mg/Kg, p.o.) for 2 weeks. Oral glucose tolerance test, and incretin and insulin levels were measured at the end of the experimental period. Results: The results showed that extract promotes better tolerance to oral glucose overload, in addition to a statistically significant (p<0.001) increase in blood levels of incretin and insulin, compared to the hyperglycemic rats. Conclusion: It is concluded that the ethanolic extract of P. ruscifolia leaves has a hypoglycemic effect in hyperglycemic animals by a mechanism that involves the incretin-insulin system.

RESUMEN Antecedentes: la diabetes mellitus es una enfermedad metabólica cuyo tratamiento se basa en el uso de agentes hipoglicemiantes orales o insulina. Una opción al tratamiento son las plantas medicinales y en ese sentido, estudios previos en animales con hojas de Prosopis ruscifolia (Pr) han demostrado efecto hipoglicemiante. Objetivo: en este trabajo se reporta el efecto de P. rusciofolia (Pr) en la secreción de insulina e incretina, en ratas hiperglicémicas por aloxano. Metodología: se emplearon cuatro grupos de ratas Wistar (n=10). Dos grupos con glicemia normal que fueron tratadas con agua Pr (75 mg/Kg, per os, p.o.) y dos grupos con hiperglicemia inducida por la inyección intraperitoneal de aloxano recibieron agua Pr (75 mg/Kg, per os, p.o.) durante dos semanas. Se midieron la tolerancia oral a la glucosa, y los niveles de incretina e insulina al final del periodo de experimentación. Resultados: se encontró que el extracto promueve una mayor tolerancia a la sobrecarga de glucosa, y además un incremento significativo (p<0.001) de los niveles de incretina e insulina en sangre, comparados al grupo de ratas hiperglicémicas. Conclusión: se concluye que e l estracto etanólico de las hojas de P. ruscifolia tienen efecto hipoglicemiante en animales hiperglicémicos por un mecanismo que incluye al sistema incretina-insulina.

La dislipidemia es un factor de riesgo para el desarrollo de enfermedades cardiovasculares, una de las principales causas de muertes a nivel mundial. En este trabajo se estudió el efecto del aguacate (Persea americana) sobre el metabolismo lipídico de ratones normo e hiperlipémicos inducidos con dieta hiperlipídica. Ratones machos, fueron distribuidos en 4 grupos DE (dieta estándar), DEa (dieta estándar y aguacate); DH (dieta hiperlipídica) y DHa (dieta hiperlipídica y aguacate) y observados por 28 días. Luego de este periodo se determinaron los niveles de Colesterol Total, Triglicéridos y col-HDL y se calcularon los valores de col-LDL, VLDL e índices de riesgo aterogénico y de riesgo coronario. El grupo DH mostró niveles de CT, TG, col-LDLy VLDL significativamente superiores (p<0,001) a los valores alcanzados en el grupo DE. En los grupos DHa y DEa se redujeron significativamente (p<0,001) las concentraciones de CT, TG, col-LDL y VLDL, en comparación al grupo DH. Los grupos DEa y DHa difieren significativamente (p<0,005) en el nivel de CT, éste último presenta valores más bajos, los otros parámetros cuantificados no mostraron diferencias significativas. No hubo diferencias significativas para los valores del col-HDL en ningún grupo de estudio. La inducción a la hiperlipemia con un modelo de dieta hiperlipídica, generó incrementos importantes en el CT, TG, col-LDL y VLDL, además de aumentar el riesgo aterogénico. El consumo de la pulpa de aguacate redujo los niveles de CT, TG, col-LDL, VLDL y el índice de riesgo aterogénico en el grupo de ratones hiperlipémicos.

Influence of avocado (Persea americana) pulp consumption on lipid metabolism in normolipidemic and diet induced hyperlipidemic mice . Dyslipidemia is a risk factor for developing cardiovascular disease, a major cause of deaths worldwide. The aim of this work is to study the effect of avocado (Persea americana), on lipid metabolism on normolipidemic and hyperlipidemic mice induced with high fat diet. Four groups of animals receiving standard diet (DE), standard and avocado diet (DEa), high fat diet (DH) and high fat and avocado diet (DHA) were used. All animals were observed for a period of 28 days. Blood sample was obtained at the end of experimentation period by cardiac puncture on anesthetized animals, and the levels of Cholesterol, triglycerides and col-HDL were de- termined and c-LDL, VLDL and atherogenic and coronary risk factors were calculated. DH group showed levels of TC, TG, c-LDL and VLDL significantly higher (p<0,001) than the values achieved in DHa group. DHa and DEa plasmatic values of TC, TG, c-LDL and VLDL were significantly reduced (p <0.001) compared to DH group. DEa and DHA groups differed significantly (p <0.005) in the level of CT, the latter has lower values, the other quantified parameters showed no significant differences. There were no significant differences for c-HDL values in any group. Hyperlipidemia induction with a model of high fat diet produced significantly increasing values of TC, TG, c-LDL and VLDL, besides of increasing the atherogenic risk. The benefit of avocado pulp consists in reduction of TC, TG, c-LDL, VLDL and the index of atherogenic risk.

Kyllinga brevifolia Rottb., Cyperaceae, rhizomes have been widely used in the Paraguayan folk medicine as digestive, diuretic, sedative, tonic, antispasmodic and sudorific. The purpose of this study is to characterize the putative sedative, anxiolytic effects of the crude hydro-ethanolic extract (CEKb) and fractions of the rhizome of K. brevifolia, in male mice. The behaviour of mice was assessed in the open field, hole board, rota-rod and elevated plus-maze (EPM) test. Oral treatment with single doses of 10, 100 and 1000 mg/kg of CEKb and 10 mg/kg of ethyl acetate fraction (KbF-ethyl-ac) increased the duration of the sleeping time induced by pentobarbital. Oral administration of 1, 10 and 100 mg/kg of CEKb and 0.1, 1 and 10 mg/kg of KbF-ethyl-ac also significantly increased the time-spent and arm entries into open arms of the elevated plus maze (EPM) versus control group. These findings indicate that K. brevifolia exerts a weak sedative and an interesting anxiolytic-like effect in mice and suggest its potential usefulness for the treatment of anxiety in humans.

Aeonium species are plants rich in phenols and terpenoids and have been widely used in the Canary folk medicine. Following our project concerning bioactive compounds from Macaronesian region, a phytochemical study was carried out to investigate the constituents of the stems of Aeonium lindleyi Webb & Berthel.,Crassulaceae. Air dried and chopped stems of this plant were extracted with ethanol in a Soxhlet apparatus and the total extract was chromatographed on silica gel to afford sixteen known compounds including, one sterol, four lupane triterpenes and eleven phenolic compounds. Their structures were elucidated by means of ¹H- and 13C-NMR spectroscopic studies and comparison of their spectral data with values in the literature. Both group of isolated metabolites are known by their diverse biological activities and they have been described as antioxidant, cytotoxic, anti-inflammatory. Our results contribute to the knowledge of A. lindleyi as a potential source of bioactive compounds.