Evaluación preclínica y estudio de estabilidad de extractos a partir del follaje de Momordica charantia Lin / Obtaining and characterizing the Momordica charantia Linn leaf extracts

El objetivo del presente trabajo fue la evaluación preclínica y el estudio de estabilidad de extractos a partir del follaje de Momordica charantia Lin. Se obtuvieron extractos acuoso e hidroalcohólico para los cuales se establecieron las especificaciones de calidad mediante la evaluación de tres lotes y se estudió su estabilidad por el método de vida de estante durante 12 meses. A los extractos se le evaluó el potencial genotóxico mediante ensayos de micronúcleos en médula ósea de ratón y aberraciones cromosómicas en linfocitos de sangre periférica. La actividad hipoglicemiante oral fue evaluada en animales con hiperglicemia temporal inducida por carga de glucosa. Como resultados se establecieron las especificaciones de calidad de los extractos acuoso e hidroalcohólico, los mismos mostraron estabilidad por 6 meses para el extracto acuoso y 12 meses para el extracto hidroalcohólico. No mostraron efecto genotóxico en los ensayos evaluados y mostraron efecto hipoglicemiante oral a la dosis de 450 mg/kg.

The objective of this investigation was the preclinical evaluation and the stability study of the Momordica charantia Linn hydroalcoholic and aqueous leaf extracts. The hydroalcoholic and aqueous extracts were obtained and the quality specifications were determined by evaluating three lots. The stability of the extracts was evaluated for 12 months. The genotoxic potential of the extracts was evaluated by mouse bone marrow micronucleus test and chromosome aberration test. The hypoglycemic effect was determined by oral glucose tolerance test. As results, the quality specifications were established and the aqueous extract was stable for 6 months and the hydroalcoholic extract for 12 months. A genotoxic effect was not observed in both extracts and the hypoglycemic effect was observed at the oral dose of 450 mg/kg of body weight.

Irritación gástrica producida por diclofenaco de sodio: estudiocomparativo de tabletas de liberación controlada en conejos / Gastric irritation of sodium diclofenac: comparative study of slow-release formulation in rabbits

El objetivo del presente trabajo fue evaluar el potencial irritante gástrico de una formulación nacional de diclofenaco de sodio de liberación controlada comparativamente con un producto de importación y con una formulación recubierta con Sucralfato, mediante un ensayo agudo y otro a dosis repetidas en conejos Nueva Zelanda tratados con una dosis de 59 mg/kg por vía oral. Las tabletas de diclofenaco formulación nacional produjeron irritación gástricaligera en el ensayo agudo, la cual fue similar a la producida condiclofenco importado y diclofenaco recubierto con sucralfato. La administración de diclofenaco formulación nacional durante 5 días en conejos produjo irritación gástrica, observándose erosión sobre la mucosa gástrica similar a la observada con la administración de diclofenaco importado. Los efectos sobre la mucosa gástrica y duodenal producidos por ambas formulaciones de diclofenaco fueron similares en el ensayo agudo y a dosis repetidas siendo factible el empleo de la formulación nacional en ensayos clínicos (AU)

The aims of the study was to evaluate the gastric irritation potential of a slow-release Cubanformulation of sodium diclofenac comparatively with the import product and with a formulation recovered with sucralfate, by means of an acute test and repeated dose test in New Zealand rabbits triedwith an oral dose of 59 mg/kg. National formulation of diclofenac produced slight gastric irritation in the acute test. This result wassimilar to the observed with the import product and sucralfate recovered diclofenac. The administration of national formulation of diclofenac for 5 days in rabbits produced gastric irritation. We observed gastric mucous erosion similar to the import diclofenac treated group. The effects causes by both formulations on the gastric and duodenal mucous were similar in the acute test and repeated dose test, being feasible the employment of the national slow-release formulation in clinical rehearsals (AU)

Comparative study of red blood cell method in rat and calves blood as alternatives of Draize eye irritation test.

INTRODUCTION: Red blood cell assay (RBC) is used to estimate potential irritation of tensioactive agents and detergents. Cell membrane lysis and cell protein denaturation are measured photometrically. This study was aimed to determine if rat blood cells can be used to predict eye potential irritation in the same way of calves blood cells in RBC assay. METHODS: We evaluated 20 cosmetic formulations using rat and calves blood according to INVITOX protocol No 37. Data of media hemolysis concentration, denaturation index and the ratio of both parameters were compared with in vivo data of eye irritancy. RESULTS: There was a significant difference (p<0.01) between H50 value when evaluated the standard SDS with red blood cell method in rat and calves blood. According to the exact probability of Fisher taking as approach the acceptance or rejection of the substance there are no significant differences between in vitro assay with calves blood and in vivo results. Not happening the same way for the RBC assay with rat blood where significant differences were obtained (p<0.01) among the classification of in vitro and in vivo test. DISCUSSION: The RBC assay using calves blood showed better results. Several test substances were false negatives with rat blood. This high false negative rate would be correctly identified by the animal test but it may also lead to increased animal consumption. For that RBC assay with calf blood cells is preferable to the employment of rat blood as screening method with a reduction and refinement strategy.

In vitro quantitative determination of ophthalmic irritancy by the chorioallantoic membrane test with trypan blue staining as alternative to eye irritation test.

The damage provoked by some substances on the chicken egg's chorioallantoic membrane (CAM) is used as an alternative assay to determine ocular irritation. There is good prediction of the eye irritation when compared to the in vivo Draize method. Nevertheless, this assay has some limitations, such as subjectivity. Hagino et al. developed an objective evaluation technique using the amount of trypan blue absorbed at the site of treatment as an indicator of injury to the CAM. The present work was aimed at the determination of ocular irritation of 21 substances (chemicals and cosmetics). We used the spectrophotometric quantification by trypan blue staining of the damage produced on CAM, of fertile chicken eggs. Results were compared with the values obtained by the traditional Draize assay. We observed a good correlation (r=0.835; p<0.0001) between the amount of dye absorbed by the CAM and the Draize eye irritation test score. The r values were 0.688; p<0.05 for cosmetics and 0.925; p<0.0001 for chemicals. Three chemicals turned as false positive and one cosmetic substance as false negative. The CAM-TBS assay is inexpensive, simple and provides an in vitro alternative method to predict the damage that chemical substances or cosmetics can cause to the ocular structures.

Toxicidad aguda oral y subcrónica en ratas de un extracto acuoso liofilizado de Ocimum tenuiflorum L / Acute and subchronic oral toxicity in rats of a lyophilized aqueous extract of Ocimum tenuiflorum L

El potencial tóxico de un extracto acuoso liofilizado fue evaluado mediante el ensayo de toxicidad aguda oral y subcrónica a 90 días en ratas Wistar de ambos sexos. Los métodos empleados fueron los descritos por las normas OECD. En el ensayo agudo se administró por vía oral la dosis de 2000 mg/kg y en el ensayo subcrónico 250, 500 y 1000 mg/kg/día durante 13 semanas. Se evaluaron los signos tóxicos y peso corporal en ambos ensayos. En el estudio subcrónico además se evaluó el consumo de alimentos, indicadores hematológicos (hemoglobina, hematocrito, recuento diferencial de leucocitos, recuento total de leucocitos y recuento total de eritrocitos) y bioquímica clínica (glucosa, alanino amino transferasa, aspartato amino transferasa, colesterol, urea, bilirrubina y creatinina). También se realizó necropsia y examen histopatológico de órganos y tejidos (corazón, riñón, hígado, bazo, cerebro, pulmón, estómago, intestino, timo, glándulas suprarrenales, tiroides, paratiroides, páncreas, glándulas salivales, ganglio cervical, testículos, vesículas seminales, próstata y ovarios) y se determinó el peso relativo de órganos (corazón, riñón, hígado, bazo, cerebro, pulmón, timo, glándulas suprarrenales, próstata, testículos y ovarios). No se apreciaron signos tóxicos ni mortalidad como consecuencia de la administración del liofilizado de Ocimum tenuiflorum L. en ninguno de los ensayos. Los parámetros analizados de peso corporal, consumo de alimentos, hematología, bioquímica, peso relativo de órganos y análisis histopatológico de órganos y tejidos no evidenciaron toxicidad significativa atribuible a la sustancia de prueba

The toxic potential of a lyophilized aqueous extract was evaluated by oral acute and 90 days subchronic toxicity in Wistar rats of both sexes. The methods used were those described by OECD guidelines. In an oral acute toxicity test, a dose of 2000 mg/kg and for subchronic toxicity test, doses of 250, 500 and 1000 mg/kg/day for 13 weeks were administered. The toxic signs and corporal weight were evaluated for both assays. In addition, in subchronic toxicity test, the food consumption, haematology (haemoglobin, haematocrit, erythrocyte count, total and differential leucocyte count) and clinical biochemistry determination (glucose, alanine aminotransferase, aspartate aminotransferase, cholesterol, urea nitrogen, total bilirubin and creatinine) were evaluated. Gross necropsy and histopathological examination of organs and tissues (heart, kidney, liver, spleen, brain, lung, stomach, intestine, thymus, adrenals, thyroid/parathyroid, pancreas, salivary glands, cervical ganglion, testicles, seminal vesicles, prostate and ovaries) were carried out and relative weight of each organ was determined (heart, kidney, liver, spleen, brain, lung, thymus, adrenals, prostate, testicles and ovaries). Oral acute and subchronic toxicity tests showed no significant toxic effects attributable to the test substance, with absence of toxic symptoms or mortality and normal weight increment, food consumption, haematology, biochemistry, organs relative weight and histopathological examination of organs and tissues