Protective effect of extract of the Camellia japonica L. on cerebral ischemia-reperfusion injury in rats / Efeito protetor do extrato da Camellia japonica L. na lesão de reperfusão isquêmica cerebral em ratos

ABSTRACT Objective: We investigated the protective effect of the extract of the Camellia japonica L. flower on cerebral ischemia-reperfusion injury in rats. Methods: The rat ischemia-reperfusion injury was induced by middle cerebral artery occlusion for 90 minutes and reperfusion for 48 hours. The animals received an intravenous injection once a day of 20, 40, 80 mg/kg extract of C. japonica for three consecutive days before the ischemia reperfusion. The learning and memory function, the infarct volume, serum malondialdehyde (MDA) level and lactate dehydrogenase activity, and extravasation of immunoglobulin G (IgG) into cerebral parenchyma were assessed as the cell damage index. Results: Pretreatment with extract of C. japonica markedly reduced the infarct volume, serum malondialdehyde level and lactate dehydrogenase activity, and markedly inhibited the extravasation of IgG. Moreover, pretreatment with extract of C. japonica may also inhibit the learning and memory deficits induced by an ischemia-reperfusion injury. Conclusion: It was concluded that pretreatment with extract of C. japonica has a protective effect on cerebral ischemia-reperfusion injury in rats.

RESUMO Objetivo: Investigamos o efeito protetor do extrato da flor de Camellia japonica L. (ECJ) na lesão de reperfusão isquêmica cerebral (I/R) em ratos. Métodos: A lesão de I/R de rato foi induzida por uma oclusão da artéria cerebral média por 90 minutos e reperfusão por 48 horas. Os animais receberam uma injeção intravenosa uma vez ao dia de 20, 40, 80 mg/kg de ECJ por três dias consecutivos antes da I/R. A função de aprendizagem e memória, o volume do infarto, o nível sérico de malondialdeído (MDA), a atividade da desidrogenase láctica e o extravasamento de imunoglobulina (IgG) no parênquima cerebral foram avaliados como índices de dano celular. Resultados: O pré-tratamento com ECJ reduziu acentuadamente o volume do infarto, o nível sérico de MDA e a atividade da desidrogenase láctica, e inibiu marcadamente o extravasamento de IgG. Além disso, o pré-tratamento com ECJ também poderia inibir os déficits de aprendizado e memória induzidos pela lesão de I/R. Conclusão: O pré-tratamento com ECJ tem um efeito protetor contra lesão cerebral de I/R em ratos.

Hypolipidemic effect of a novel biflavonoid from shells of Camellia oleifera (Abel.).

Camellia oleifera Abel. [C. oleosa (Lour.) Rehd.], an evergreen plant, is used for healthful oil production, but the shells are always discarded and need to be utilized. The present study was undertaken to explore the effect of extracts from the shells of C. oleifera on adjusting cardiovascular system. A flavonoid was obtained by reflux extraction of the shells in 70% methanol, hydrolysis in 2 M hydrochloric acid, and crystallization in acetone. Its structure was identified as a novel biflavonoid. Mice model of hyperlipidemia was setup by high fat diet for 30 d to evaluate the hypolipidemic effect of the biflavonoid at dose of 50, 100 and 200 mg/kg/d (ig). Antioxidative activity was determined by levels of malondialdehyde (MDA), superoxidase dismutase (SOD) and glutathione peroxidase (GSH-Px) in mice serum. The biflavonoid significantly controlled mice weight and liver coefficient, decreased the content of total cholesterol and triglyceride, promoted the level of high density lipoprotein in a dose dependent manner. The significant decrease of MDA content and increase of SOD and GSH-Px activity indicated it enhanced antioxidative capacity in vivo and was ascribed to hypolipidemic effect. The biflavonoid is useful in the prevention of high fat diet induced hyperlipidemia.

Histopathological Changes in Tissues of Bithynia siamensis goniomphalos Incubated in Crude Extracts of Camellia Seed and Mangosteen Pericarp

The present study was performed to observe histopathological changes in tissues of Bithynia siamensis goniomphalos (Gastropoda, Bithyniidae) incubated in crude extract solutions of camellia (Camellia oleifera) seed and mangosteen (Garcinia mangostana) pericarp, and furthermore to estimate the molluscicidal effects of 2 plant substances. Substantial numbers of bithyniid snails were incubated in various concentrations of 2 plant solution for 24 hr. As the positive control, snails incubated in various concentrations of niclosamide, a chemical molluscicide, were used. The histopathological findings were observed in sectioned snail specimens of each experimental and control groups. The results showed that both camellia and mangosteen extracts had molluscicidal effects at 24 hr with 50% lethal concentration (LC50) at concentrations of 0.003 and 0.002 g/ml, respectively, while niclosamide had LC50 at concentrations 0.599 ppm. B. siamensis goniomphalos snail tissues (foot, gill, and digestive system) showed disruption of columnar muscle fibers of the foot, reduction of the length and number of gill cilia, numerous mucous vacuoles, and irregularly shaped of epithelial cells. Irregular apical and calciferous cells, dilatation of the digestive gland tubule, and large hemolymphatic spaces, and irregular apical surfaces, detachment of cilia, and enlargement of lysosomal vacuoles of epidermis were also shown in all groups. By the present study, it is confirmed that 2 plants, camellia and mangosteen, are keeping some substance having molluscicidal effects, and histopathological findings obtained in this study will provide some clues in further studies on their action mechanisms to use them as natural molluscicides.