New flavonoid with antidiabetic and antioxidant potential from Tetrastigma angustifolia (Roxb. ) Deb leaves

Ethnomedicinal survey documents the traditional practices of Tetrastigma angustifolia leaves in the management of diabetes in the North-eastern region of India. The present study was aimed at isolation of possible antidiabetic principle(s) from T. angustifolia leaves and evaluation of antidiabetic efficacy of isolated compound(s) in experimental animal model. The methanolic extract of T. angustifolia leaves was obtained by Soxhlet extraction method and subjected to silica gel column chromatography (100-200 mesh). Fraction 18-176 chloroform:methanol (70:30) yielded a pale yellow colored compound. The structure of pure compound was elucidated with the help of UV, IR, NMR and Mass spectrometric/techniques. The antioxidant activity of the isolated compound was evaluated in vitro by various radical scavenfing assay methods.. Oral acute toxicity study was carried out according to OECD guideline 423 in Wistar rats. The antidiabetic efficacy of the isolated compound was evaluated in STZ-induced diabetic rats at the dose of 5 mg/kg b.w. for duration of 21 days. The present study reports a new flavocnoid compound isolated from the methanolic extract of T. angustifolia leaves and identified as 8-hydroxyapigenin 7-O-D-glucopyranoside. The flavonoid compound exhibited potent antidiabetic (hypoglicemic) activity in STZ-induced diabetic rats with promising antioxidant (radical scavenging activity) potential in vitro.

Estudo de biocompatibilidade in vivo e in vitro do extrato hidroalcoólico de Cissus sicyoides L. - Vitaceae em ratos / Study of in vivo and in vitro biocompatibility of Cissus sicyoides L. - Vitaceae hydroalcoholic extracts in rats

Biocompatibilidade é a capacidade de um material exercer funções específicas quando aplicado em contato com tecidos vivos de determinado hospedeiro, sem, contudo, causar danos ou prejuízo ao mesmo. Este trabalho objetivou determinar a biocompatibilidade in vivo e in vitro do extrato hidroalcoólico do Cissus sicyoides L - Vitaceae. Foram utilizados 30 ratos (Rattus novergicus albinus wistar), com idade entre 45 e 90 dias e pesando entre 170 e 260 g. Os animais foram divididos em 3 grupos (A1, A2 e A3) de 6 animais cada para o teste in vivo, os quais foram sacrificados com 2, 4 e 6 dias, respectivamente. Para o teste in vitro, foram utilizados 12 animais para obtenção do índice de aderência e da capacidade fagocítica dos macrófagos de ratos do grupo controle e do grupo experimental. Nos resultados encontrados no teste in vivo, conclui-se que o extrato apresentou-se biocompatível, visto que não provocou alterações significativas no tecido. Já no teste in vitro, o mesmo não se apresentou biocompatível, pois o extrato puro apresentou índice de aderência baixo (7,1) e taxa de fagocitose elevada (35,7), indicando diferença significante quando comparado ao controle. Porém, quando diluído, o extrato se mostrou inócuo, devido ao aumento dos valores do índice de aderência nas concentrações de 1/10 (61,4) e 1/100 (74,3) nos ensaios, as quais não apresentaram diferença significante quando comparadas ao controle. Após a análise dos dados, concluiu-se que a solução diluída do extrato hidroalcoólico do Cissus sicyoides L. não causa danos ou prejuízos. Entretanto, como nem todos os efeitos farmacológicos foram testados no presente trabalho, não se pode inferir automaticamente que ele é biocompatível em todos os casos.

Biocompatibility is the ability of a material to perform specifictasks when applied to living tissues without causing damage or injuries to it. Thus, this study aimed at determining the in vivo and in vitro biocompatibility of Cissus sicyoides L. - Vitaceae hydroalcoholic extracts. A total of 30 rats (Rattus norvegicus Albinus Wistar), with ages ranging from 45 to 90 days and weighing between 170 and 260g were used. The animals were divided into 3 groups (A1, A2 and A3) with 6 animals each, for the in vivo test, which were sacrificed after 2, 4 and 6 days, respectively. For in vitro test, 12 animals were used to obtain the index of adherence and phagocytic ability of macrophages of rats from the control and the experimental groups. In results found for the in vivo test, it was concluded that the extract was biocompatible, whereas no significant changes were observed in the tissue. As to the in vitro test, the extract was not biocompatible, since the pure extract showed a low rate of adherence (7.1) and a high rate of phagocytosis (35.7), indicating a significant difference when compared to the control group. However, when diluted, the extract was shown to be harmless, due to an increase in the values of the adherence index at the following concentrations : 1/10 (61.4) and 1/100 (74.3) in the tests, which showed no significant differences when compared to the control group. After analyzing the data, it was concluded that since the infusion of the plant is a kind of dilution, its use does not cause any harm to the body. A new study is necessary at the moment to possibily demonstrate its effects on the long term.

Requerimientos germinativos de enredaderas características del Chaco Serrano de Córdoba, Argentina / Germinating requirements of common vines from Chaco Serrano of Córdoba, Argentina

Vines are conspicuous elements of floras in different ecosystems. Patterns of distribution and ecology of this group has been studied at regional scales, mainly in tropical areas, but less is known about factors affecting their distribution at smaller scales. In this study, the germinating requirements of common vines from two plant communities (open shrubland and woodland) in xerophytic mountain forests (Chaco serrano) were studied. A total of 21 species were selected and classified as typical of woodland, shrubland, or indifferent. Experimental treatments were three temperature regimes (15-5ºC, 25-15ºC and 35-20ºC), in light (12-12h daily photoperiod) and in continuous darkness. Total germination percentage, the relative light germination (RLG) and germination rate (T50) were recorded. Among results we found that the temperature was the main factor triggering the germination process. No differences in the mean RLG and T50 between woodland and shrubland patches were found. The patterns observed in this work support the idea that, independently of patch type, germination is associated with temperature of the time of the year when most of the rainfall occurs. Germination of the studied species would be responding to macroclimate’s factors (seasonality of climate and rainfall), rather than to a microclimate. This indicates that differences in species composition between patches would not be due to the factors studied, rather than to characteristics of the later stages of the cycle life.

Las enredaderas son elementos conspicuos de la flora de diferentes ecosistemas. Numerosos estudios basados en patrones de distribución y ecología de este grupo de plantas se han realizado a escala regional, se conoce poco sobre los factores que afectan su distribución a nivel local. Se estudiaron los requerimientos germinativos de 21 enredaderas del Bosque chaqueño serrano de Córdoba, las cuales fueron clasificadas en típicas de bosques, matorrales e indiferentes. Se llevaron a cabo experimentos de germinación en tres regímenes de temperatura (15-5ºC, 25-15ºC y 35-20ºC), en luz (12-12hr luz-oscuridad) y oscuridad permanente. Se registró el porcentaje final de germinación, el índice de germinación relativa a la luz (GRL) y la velocidad de germinación (T50). La temperatura fue el principal factor regulador del proceso germinativo. El GRL y el T50 no registraron diferencias entre fisonomías. Los patrones observados apoyan la idea de que la germinación de este grupo de plantas estaría respondiendo a factores macroclimáticos (estacionalidad del clima y las precipitaciones), más que a un microclima (factores asociados a la fisonomía del sitio). La composición diferencial de enredaderas en los parches de bosques y arbustos no estaría explicada por los factores estudiados, sino por características de las etapas posteriores a la semilla.