Preclinical studies of hydroalcoholic extract of Calea uniflora Less / Estudios preclínicos de extracto hidroalcohólico de Calea uniflora Less

Calea uniflora Less known popularly as Arnica in Brazil, is a native plant from Brazil, popular used by coastal populations from south of Santa Catarina. The purpose of this study was to verify the safety profile in of hydroalcoholic extract of C. uniflora in florescences.The hydroalcoholic extract of C. uniflora in florescences was evaluated for its acute and sub-acute toxicity. Acute topical toxicity was performed using the methodology of guideline 402 from OECD. Acute oral toxicity was performed using the methodology of guideline 423 from OECD and sub-acute toxicity was performed using the methodology adapted of guideline 407 from OECD. The single dose for oral or topical administration of C. uniflora showed DL50> 5000 mg/kg b.w. The sub-acute treatment induced animal death in groups, which was administered extract in the doses 100, 250, 500 and 1000 mg/kg. The main signs of toxicity observed were respiratory difficulty, increase in lung weigh, lung damage and muscular relation. The topical or oral administration of C. uniflora extract in short period did not caused toxicological effects in animals, however, when administered for a longer period and in concentrations of 250, 500 and 1000 mg/kg (oral.) caused lung damage and even the death of the animal.

Calea uniflora Less conocida popularmente como Arnica en Brasil, es una planta nativa de Brasil, popularmente utilizada por poblaciones costeras del sur de Santa Catarina. El objetivo de este estudio fue verificar el perfil de seguridad del extracto hidroalcoólico de inflorescencias de C. uniflora. El extracto hidroalcoólico de inflorescencias de C. uniflora fue evaluado en cuanto a su toxicidad aguda y subaguda. La toxicidad tópica aguda se realizó utilizando la metodología de la directriz 402 de la OECD. La toxicidad oral aguda fue realizada usando la metodología de la directriz 423 de la OECD y la toxicidad subaguda fue realizada usando la metodología adaptada de la directriz 407 de la OECD. La dosis única para administración oral o tópica de C. uniflora mostro DL50> 5000 mg/kg. El tratamiento subagudo indujo la muerte de animales en grupos a los que se administró extracto en las dosis de 100, 250, 500 y 1000 mg/kg. Los principales signos de toxicidad observados fueron dificultad respiratoria, aumento del peso del pulmón, daño pulmonar y relación muscular. La administración tópica oral del extracto de C. uniflora a corto plazo no causó efectos toxicológicos en los animales, mientras que, cuando se administró por un período mayor y en las concentraciones de 250, 500 y 1000 mg/kg (oral) causaron danos en los pulmones y hasta la muerte del animal.

Caracteres anatômicos de folha e caule de Calea uniflora Less., Asteraceae / Anatomical characters of the leaf and stem of Calea uniflora Less., Asteraceae

Diversas espécies de Calea são utilizadas como medicinais e vários estudos químicos têm sido conduzidos para identificar compostos relevantes no gênero, no entanto, poucos enfocam aspectos morfoanatômicos. Este trabalho tem por objetivo caracterizar morfologicamente a folha e o caule de Calea uniflora Less., a fim de fornecer subsídios para a identificação da espécie. O material foi submetido às microtécnicas fotônica e eletrônica de varredura usuais. A lâmina foliar possui epiderme uniestratificada revestida por cutícula delgada e estriada. Em ambas as faces, ocorrem estômatos anomocíticos e anisocíticos, além de tricomas glandulares e tectores. Estes são pluricelulares e unisseriados, com ápice agudo. Os glandulares podem ser pluricelulares e plurisseriados ou capitados e inseridos em depressão na epiderme. O mesofilo é isobilateral e a nervura central é biconvexa, sendo percorrida por um feixe vascular colateral. O caule mostra secção circular e epiderme unisseriada, com tricomas similares aos da folha. Colênquima angular e clorênquima alternam-se no córtex, fibras perivasculares apõem-se ao floema, o arranjo vascular é colateral e a medula compõe-se de células parenquimáticas. Dutos secretores acompanham o sistema vascular na folha e no caule.

Various species of Calea are considered medicinal and several investigations have been carried out to identify relevant chemical substances in the genus, however, few studies have dealt with morpho-anatomical aspects. This work aimed to analyse the morphological characters of the leaf and stem of Calea uniflora Less., in order to contribute for the species identification. The plant material was prepared according to usual light and scanning microtechniques. The blade has uniseriate epidermis coated with thin and striate cuticle. Anomocytic and anisocytic stomata are seen on both surfaces, as well as glandular and non-glandular trichomes. The latter is pluricellular and uniseriate, with acute apex. The glandular trichomes are pluricellular and multiseriate or capitate and located in epidermal depression. The mesophyll is isobilateral, and the midrib is biconvex and traversed by a collateral vascular bundle. The stem shows circular transection and uniseriate epidermis, with trichomes similar to the leaf. Angular collenchyma and chlorenchyma alternate in the cortex, perivascular fibres adjoin the phloem, the vascular arrangement is collateral and the pith consists of parenchymatic cells. Secretory ducts are associated with the vascular system of the leaf and stem.