RESUMO
Human African trypanosomiasis is a neglected tropical disease in sub Saharan Africa that is fatal if left untreated. In a search for new natural products with antitrypanosomal activity, we recently identified abruquinones B and I from Abrus precatorius as potent in vitro trypanocidal compounds with high selectivity indices. To obtain sufficient compound for in vivo efficacy tests in mice, a second batch of plant material was re-collected and extracted. However, the chemical profiles of the two batches differed, and additional abruquinones were isolated and identified by HR-ESI-MS, and 1D and 2D NMR ((1)H, (13)C, COSY, HMBC, HSQC, and NOESY) spectroscopy. Abruquinones J (1), K (2), and L (3) were new, while abruquinones A (4) and D (5) were known from the first batch of plant material. The absolute configuration of compounds 1 to 3 was determined by comparison of electronic circular dichroism (ECD) spectra with calculated ECD data. Compounds 2 to 5 showed high in vitro activity against T. b. rhodesiense (IC50 of 0.01, 0.02, 0.02 and 0.01 µM, respectively), and remarkable SIs of 508, 374, 1379, and 668, respectively.
Assuntos
Abrus/química , Tripanossomicidas/isolamento & purificação , Animais , Benzopiranos/isolamento & purificação , Benzopiranos/toxicidade , Benzoquinonas/isolamento & purificação , Benzoquinonas/toxicidade , Testes de Sensibilidade Microbiana , RatosRESUMO
Seeds of Abrus precatorius L., Fabaceae, are commonly used as purgative, emetic, aphrodisiac and in nervous disorder in traditional and folk medicines. In present study petroleum ether and ethanolic extracts of A. precatorius seeds are evaluated for reversal of androgen (testosterone by i.m route) induced alopecia in male albino wistar rats and compared to topical administration of standard antiandrogenic drug finasteride for 21 days. The results were reflected from visual observation and histological study of several skin sections via various parameters as anagen to telogen ratio and follicle density/mm area of skin surface. The animal of group 1 who were treated with only testosterone became alopecic on visual observation. Animals of Group 2, 3 and 4 who were treated with finasteride, petroleum ether and ethanolic extract of seed respectively topically along with testosterone (i.m) did not developed alopecia. To investigate the mechanism of observed activity, in vitro experiments were performed. Inhibition of 5α-reductase activity by extracts and finasteride suggest that they reversed androgen induced alopecia by inhibiting conversion of testosterone to dihydrotestosterone (potent androgen responsible for androgenic alopecia). So it may be concluded that petroleum ether and ethanolic extract of A. precatorius seed posses anti androgenic alopecia activity due to inhibition of 5α-reductase enzyme.
RESUMO
In developing countries, herbal medicines have continued to remain significant and readily patronized. Numerous plants have been used historically to reduce fertility and modern scientific research has confirmed antifertility effect in some of the herbs tested. To investigate the effects of Abrus precatorius (AP) on the histology of the ovary, oviduct and uterus of female Sprague-Dawley (S-D) rat. A total of 40, 68 week old 4-day cycling female S-D rats were used. They were divided into the treatment, control and reversibility groups. The treatment and reversibility groups were fed oral AP seed extract (50 mg/kg b.w) for 32 days. A fraction of the rats in reversibility group was treated with distilled water for another 32 days. The control group were used to compare events in the other groups. At the end of the experimental durations animals were sacrificed under light chloroform anesthesia. Their ovaries, uteri and oviducts harvested for microscopic studies. Comparing the control histological sections to the treated groups: the ovaries showed decreased size, large follicular distension and extensive stromal necrosis with compromised cellularity. The uterine tubes revealed appreciable mucosal reduction. The uteri exhibited reduction in the layer of endometrial thickness. On the other hand sections in reversal experimental rats were comparable to control. The rats treated with AP seed extract at dose 50 mg/kg b.w induced reversible alterations in ovaries, uterine and uteri in S-D.
En los países en desarrollo, las hierbas medicinales siguen siendo de gran importancia y de fácil utilización. Numerosas plantas se han utilizado históricamente para reducir la fertilidad y la investigación científica moderna ha confirmado el efecto anti-fertilidad en algunas de las hierbas estudiadas. Para investigar los efectos de Abrus precatorius (AP) sobre la histología del ovario, oviducto y útero de ratas Sprague-Dawley (SD), fueron utilizadas un total de 40 ratas SD hembras de 6-8 semanas de edad en el día 4 del ciclo. Se dividieron en grupos de tratamiento, control y reversibilidad. Los grupos de tratamiento y reversibilidad se alimentaron por vía oral con el extracto de semilla de AP (50 mg/kg de peso corporal) durante 32 días. Una fracción de las ratas del grupo de reversibilidad se trató con agua destilada durante otros 32 días. El grupo de control se utilizó para comparar los eventos en los otros grupos. Al finalizar el periodo experimental los animales fueron sacrificados bajo anestesia con cloroformo. Los ovarios, útero y los oviductos fueron procesados para los estudios microscópicos. Al comparar las secciones de control histológico con los grupos tratados, los ovarios mostraron disminución del tamaño, gran distensión folicular y necrosis estromal extensa con celularidad comprometida. Las tubas uterinas revelaron una reducción apreciable de la mucosa. El útero mostró una reducción de grosor en la capa endometrial. Por otra parte, las secciones del grupo de ratas experimentales con reversibilidad fueron comparables a los de control. Las ratas tratadas con extracto de semilla de AP en dosis de 50 mg/kg de peso corporal indujeron alteraciones reversibles en los ovarios, oviductos y úteros en ratas SD.
Assuntos
Animais , Feminino , Ratos , Abrus/farmacologia , Extratos Vegetais/farmacologia , Ovário , Tubas Uterinas , Útero , Abrus/química , Ovário/ultraestrutura , Ratos Sprague-Dawley , Tubas Uterinas/ultraestrutura , Útero/ultraestruturaRESUMO
Five bovines immunized against the toxicity of the seeds of Abrus precatorius L. (jequiriti bean) did not get poisoned or only slightly so when the seeds of Ricinus communis L. (castor bean) were given in amounts that in bovines, which never before ingested the seeds of A. precatorius or R. communis, caused moderate to severe poisoning or even death. A sixth bovine, which was not well immunized against the toxic action of the seeds of A. precatorius, was severely poisoned when given a high dose of the seeds of R. communis. On the other side, from five bovines immunized against the toxic action of the seeds of R. communis four were severely poisoned and the fifth one moderately when the seeds of A. precatorius were given in doses that in bovines, which never before ingested seeds of R. communis or A. precatorius, caused slight to severe poisoning. It is concluded that bovines immunized against the toxic action of the seeds of A. precatorius are resistant to the toxic action of the seeds of R. communis, but that the contrary is not the case; this is, bovines immunized against the toxic action of the seeds of R. communis were not protected against the poisoning by A. precatorius. Earlier studies by other authors had shown that the toxalbumins of the seeds of A. precatorius and R. communis, respectively abrin and ricin, are different as to their antigenic properties. A possible explanation for the difference in results can be.that in the present study polygastric animals were used which received the seeds orally, but in the earlier studies monogastric animals received the seeds or toxins by parenteral route. The administration of the fresh leaves or the pericarp of the fruits R. communis to bovines, which had been immunized against the action of the seeds of the plant, had the same toxic effect as to not immunized animals, showing that the immunity due to ricin does not give protection against the action of ricinin, the toxic principle of the leaves and the pericarp.
Cinco bovinos imunizados contra a ação tóxica das sementes de Abrus precatorius L. ("tento", "jiquiriti") não adoeceram ou somente levemente pela administração das sementes de Ricinus communis L. ("mamona"), em doses que em bovinos que antes nunca ingeriram sementes de A. precatorius ou R. communis, causaram intoxicação de intensidade de grau moderado a acentuado ou até a morte. Um sexto bovino, que não ficou bem imunizado contra a ação tóxica das sementes de A. precatorius, adoeceu em grau acentuado pela administração de dose elevada das sementes de R. communis. Já dos cinco bovinos imunizados contra a ação tóxica das sementes de R. communis quatro adoeceram em grau acentuado, oquinto em grau moderado, pela administração das sementes de A. precatorias em doses que em bovinos que antes nunca ingeriram sementes de R. communis ou A. precatorius causaram intoxicação de intensidade leve a acentuada. Estes resultados permitem concluir que bovinos imunizados contra a ação tóxica das sementes de A. precatorius são resistentes à ação tóxica das sementes de R. communis, mas que o contrário não ocorre, isto é, bovinos imunizados contra a ação tóxica das sementes de R. communis, não se mostraram protegidos contra a intoxicação por A. precatorius. Estudos anteriores por outros autores mostraram que as toxalbuminas de A. precatorius e R. communis, respectivamente abrina e ricina, são diferentes do ponto de vista antigênico. Uma explicação para a divergência desses resultados com os nossos poderia estar no fato de que no presente estudo foram usados poligástricos que receberam as sementes por via oral, enquanto que nos estudos anteriores foram usados monogástricos em que as sementes ou as toxinas foram aplicadas por via parenteral. A administração de folhas frescas ou do pericarpo do fruto de R. communis a bovinos imunizados contra a ação das sementes desta planta tiveram o mesmo efeito tóxico que em animais não imunizados, demonstrando que a imunidade conferida pela ricina não inibe a ação da ricinina, o principio tóxico das folhas e do pericarpo.