ABSTRACT Leishmaniasis is a disease that affects millions of people and it is an important public health problem. The drugs currently used for the treatment of leishmaniasis present undesirable side effects and low efficacy. In this study, we evaluated the in vitro activity of Melampodium divaricatum (MD-EO) and Casearia sylvestris (CS-EO) essential oils (EO) against promastigote and amastigote forms of Leishmania amazonensis. Sesquiterpenes E-caryophyllene (56.0%), germacrene D (12.7%) and bicyclogermacrene (9.2%) were identified as the main components of MD-EO, whereas E-caryophyllene (22.2%), germacrene D (19.6%) and bicyclogermacrene (12.2%) were the main constituents of CS-EO. CS-EO and E-caryophyllene were active against promastigote forms of L. amazonensis (IC50 24.2, 29.8 and 49.9 µg/mL, respectively). However, MD-EO, CS-EO and E-caryophyllene were more active against amastigote forms, with IC50 values of 10.7, 14.0, and 10.7 µg/mL, respectively. E-caryophyllene presented lower cytotoxicity against macrophages J774-A1 (CC50 of 62.1 µg/mL) than the EO. The EOs and E-caryophyllene should be further studied for the development of new antileishmanial drugs.

ABSTRACT Considering the reported activity of carvone in the literature, this study aimed to evaluate the antimicrobial, cytotoxic and chemopreventive activities of (+)- and (-)-carvone, (+)- and (-)- hydroxydihydrocarvone and α,β-epoxycarvone. (+)-Hydroxydihydrocarvone (HC+), (-)-hydroxydihydrocarvone (HC-) and α,β-epoxycarvone (EP) were obtained by synthesis using (+)-carvone (C+) or (-)-carvone (C-) as precursors. The antifungal activity (MIC and MFC) were evaluated against Candida parapsilosis, C. tropicalis, C. krusei and C. albicans and the antibacterial activity (MIC and MBC) against Escherichia coli and Staphylococcus aureus. The cytotoxicity assays were performed with human cancer cell lines HepG-2 and SiHa and the normal strain MRC-5 through sulphorrodamine B assay. Chemoprevention was evaluated through quinone reductase assay. Our results showed no cytotoxicity on tumor and normal cell lines and no induction of the quinone reductase enzyme. C- and HC- presented activity against E. coli. All compounds presented weak antifungal activity against C. tropicalis and C. parapsilosis. EP and C+ showed moderate activity against C. krusei. Results suggest the potential use of carvones and its derivatives as antifungal agents against Candida yeasts. The absence of cytotoxicity in cell lines indicates safety in the use of these compounds.

ABSTRACT This study was to develop, characterize, and evaluate the physical-chemical stability, in vitro antioxidant activity and in vitro safety profile of liquid crystalline systems (LCS) and microemulsions (MEs) with and without organic cocoa (OC) extract. LCS stabilized by surfactant polyoxyethylene 20 cetyl ether, containing water and oleic acid were studied. LCS and MEs were characterized using polarized light microscopy, small angle X-ray scattering, rheology and in vitro bioadhesion, and were evaluated for a period of 30 days by visual aspects, centrifuge test, pH value and relative density. PLM and SAXS assays showed the presence of domains of MEs, cubic and hexagonal mesophasephases, varying the proportions of the components of the formulations; where in the addition of the extract did not change rheological behavior of the formulations. All of the formulations were stable in the period analyzed and presented higher bioadhesive strength. In vitro antioxidant activity suggests that LCS and MEs presented a high capacity to maintain the antioxidant activity of OC extract. The results showed that the incorporation of OC in LCS improved the safety profile, according to cytotoxicity assays of systems may be a promising platform to OC extract for topical application for the potential treatment of skin disorders.

RESUMOCasearia sylvestris Swartz é uma planta medicinal amplamente distribuída no Brasil. Ela possui atividade anti-inflamatória, antiulcerogênica e antitumoral e é popularmente utilizada para tratar envenenamentos ofídicos, ferimentos, diarreia, gripes e resfriados. Suas folhas são ricas em diterpenos clerodânicos tricíclicos oxigenados, particularmente casearinas. Aqui, nós avaliamos as atividades antioxidantes de um fração com casearinas (FC) isolada de C. sylvestrise as alterações histológicas no sistema nervoso central e fígados de camundongos Mus musculus. Primeiramente, estudos in vitro(0,9, 1,8, 3,6, 5,4 e 7,2 μg/mL) revelaram valores de CE50 de 3,7, 6,4 e 0,16 µg/mL para nitrito, radical hidroxila e níveis de TBARS, respectivamente. Em seguida, a FC (2,5, 5, 10 e 25 mg/kg/dia) foi administrada intraperitonealmente por 7 dias consecutivos em camundongos Swiss. Os níveis de nitrito no hipocampo (26,2, 27,3, 30,2 e 26,6 µM) e no corpo estriado (26,3, 25,4, 34,3 e 27,5 µM) aumentaram em todos os animais tratados com a FC (P < 0.05). As menores doses reduziram os níveis de glutationa reduzida, de catalase e de TBARS no hipocampo e no corpo estriado. Com exceção da redução na formação de TBARS, a FC demonstrou atividade antioxidante apenas in vitro. Os animais exibiram alterações histológicas que sugerem neurotoxicidade e hepatotoxicidade, indicando a necessidade de cuidados em relação ao consumo de preparações medicinais à base de Casearia sylvestris.

ABSTRACTCasearia sylvestris Swartz is a medicinal plant widely distributed in Brazil. It has anti-inflammatory, antiulcer and antitumor activities and is popularly used to treat snakebites, wounds, diarrhea, flu and chest colds. Its leaves are rich in oxygenated tricyclic cis-clerodane diterpenes, particulary casearins. Herein, we evaluated the antioxidant activities of a fraction with casearins (FC) isolated from C. sylvestrisand histological changes on the central nervous system and livers of Mus musculus mice. Firstly, in vitro studies (0.9, 1.8, 3.6, 5.4 and 7.2 μg/mL) revealed EC50 values of 3.7, 6.4 and 0.16 µg/mL for nitrite, hydroxyl radical and TBARS levels, respectively. Secondly, FC (2.5, 5, 10 and 25 mg/kg/day) was intraperitoneally administered to Swiss mice for 7 consecutive days. Nitrite levels in the hippocampus (26.2, 27.3, 30.2 and 26.6 µM) and striatum (26.3, 25.4, 34.3 and 27.5 µM) increased in all treated animals (P < 0.05). Lower doses dropped reduced glutathione, catalase and TBARS levels in the hippocampus and striatum. With the exception of this reduction in TBARS formation, FC displayed only in vitro antioxidant activity. Animals exhibited histological alterations suggestive of neurotoxicity and hepatotoxicity, indicating the need for precaution regarding the consumption of medicinal formulations based on Casearia sylvestris.

Considerando o uso popular de Casearia sylvestris Sw., Salicaceae, para o tratamento de problemas gástricos e resultados pré-clínicos que mostraram potencial atividade anti-ulcerogênica, foi realizado um screening farmacológico para avaliar a atividade biológica de outras espécies de Salicaceae. Para isso, foi utilizado um ensaio de inibição de proteases como um modelo farmacológico molecular para screening de extratos com atividade anti-ulcerogênica. Os extratos etanólico e aquoso dos galhos e folhas de C. gossypiosperma, C. decandra e C. rupestris mostraram inibição da atividade da pepsina em aproximadamente 50% com a concentração de 1 μg/mL. Curiosamente, C. obliquoa e Flacourtia ramontchi não apresentaram atividade sobre a pepsina, mas seus extratos mais apolares mostraram atividade inibitória sobre a subtilisina. A fração enriquecida de diterpenos clerodânicos mostrou atividade inibitória (42,75%) sobre a pepsina com a concentração de 1 μg/mL, mas não sobre a subtilisina (23,76%). Os resultados obtidos com os extratos e folhas das espécies testadas mostraram um padrão de atividade diferente sobre os dois tipos de proteases, a pepsina e a subtilisina, as quais estão relacionadas com diferentes tipos de atividades biológicas. Ainda mais, os resultados com a fração enriquecida de diterpenos clerodânicos sugerem que estas substâncias podem estar relacionadas com a atividade do extrato bruto de C. sylvestris.

Considering the traditional use of Casearia sylvestris Sw., Salicaceae, to threat gastric injuries and the pre-clinical studies showing its efficacy we aimed to screen other species to explore the biological activity of some species of this family. For this, we used a protease inhibition assay as a model for searching gastric anti-ulcer plant extracts. The ethanolic and aqueous extracts from branches and leafs of C. gossypiosperma, C. decandra and C. rupestris showed high percentage inhibition of pepsin, approximately 50%, with 1 μg/mL concentration. Curiously, C. obliquoa and Flacourtia ramontchi did not inhibit pepsin, but its most apolar extract showed inhibitory activity in the subtilisin assay. The enriched fraction of clerodane diterpenes inhibited the activity (42.75%) of pepsin with 1 ug/mL, but it did not inhibit subtilisin (23.76%). The results obtained with apolar and polar extracts from branches and leaves of some species of Salicaceae showed a different pattern of inhibition of two proteases, the aspartic pepsin and the serinic subtilisin, related with different biological activities. The results with the enriched fraction of clerodane diterpenes suggests that the activity observed with the C. sylvestris may be related with the presence of these substances in the crude extract.