Otília Deusdênia L. Pessoa

In-vitro and in-vivo antitumour activity of physalins B and D from Physalis angulata

We have evaluated the in‐vitro and in‐vivo antitumour activity of physalin B and physalin D isolated from the aerial parts of Physalis angulata. In‐vitro, both compounds displayed considerable cytotoxicity against several cancer cell lines, showing IC50 values in the range of 0.58 to 15.18 μg mL−1 for physalin B, and 0.28 to 2.43 μg mL−1 for physalin D. The antitumour activity of both compounds was confirmed in‐vivo using mice bearing sarcoma 180 tumour cells. The in‐vivo antitumour activity was related to the inhibition of tumour proliferation, as observed by the reduction of Ki67 staining in tumours of treated animals. Histopathological examination of the kidney and liver showed that both organs were affected by physalin treatment, but in a reversible manner. These compounds were probably responsible for the previously described antitumour activity of ethanol extracts of P. angulata, and their identification and characterization presented here could explain the ethnopharmacological use of this species in the treatment of cancer.

Topical anti-inflammatory potential of Physalin E from Physalis angulata on experimental dermatitis in mice

The anti-inflammatory effect of physalin E, a seco-steroid isolated from Physalis angulata L. was evaluated on acute and chronic models of dermatitis induced by 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and oxazolone, respectively, in mouse ear. The changes in ear edema/thickness, production of pro-inflammatory cytokines (TNF-alpha and IFN-gamma), myeloperoxidase (MPO) activity, and histological and immunohistochemical findings were analysed, as indicators of dermal inflammation. Similar to dexamethasone, topically applied Physalin E (0.125; 0.25 and 0.5 mg/ear) potently inhibited the TPA and oxazolone-induced dermatitis, leading to substantial reductions in ear edema/thickness, pro-inflammatory cytokines, and MPO activity. These effects were reversed by mifepristone, a steroid antagonist and confirmed by immunohistochemical and histopathological analysis. The data suggest that physalin E may be a potent and topically effective anti-inflammatory agent useful to treat the acute and chronic skin inflammatory conditions.

Antitumor Activity of the Essential Oil from the Leaves of Croton regelianus and Its Component Ascaridole

Croton regelianus Muell. Arg., popularly known as ‘velame‐de‐cheiro’, is a native plant from the Northeast of Brazil used in folk medicine to treat diseases of different kinds, including malignant tumors. In this study, the in vitro and in vivo antitumor effects of the essential oil from the leaves of C. regelianus and ascaridole, one of the main constituents, were investigated. In vitro, the essential oil and ascaridole displayed cytotoxicity, showing IC50 values in the range of 22.2 to 48.0 μg/ml in HL‐60 and SF‐295 cell lines for the essential oil, and 6.3 to 18.4 μg/ml in HL‐60 and HCT‐8 cells lines for ascaridole, respectively. The in vivo study, using sarcoma 180 as a tumor model, demonstrated inhibition rates of 28.1 and 31.8% for essential oil, at the 50 and 100 mg/kg, while ascaridole inhibition rates were 33.9% at 10 mg/kg and 33.3% at 20‐mg/kg doses. Histopathological examination showed that the organs were only weakly affected by the treatment. In conclusion, ascaridole has an interesting antitumor activity in sarcoma 180 murine model, probably related to the described cytotoxic activity, and, moreover, its presence in the essential oil from the leaves of C. regelianus could explain, at least in part, the ethnopharmacological use of this plant in the treatment of cancer.

Larvicidal and Nematicidal Activities of the Leaf Essential Oil of Croton regelianus

The chemical composition of the leaf essential oil of Croton regelianus collected from wild plants growing in two different sites at Ceará State (Brazil) was analyzed by GC/MS and GC‐FID. Twenty monoterpenoids, representing more than 96% of the chemical composition of the oils, were identified and quantified. The oils showed similar chemical composition but considerable variation in the levels of each constituent. Ascaridole (33.9–17.0%), p‐cymene (22.3–21.6%), and camphor (13.0–3.1%) were the predominant constituents. The monoterpene ascaridole was isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti and Artemia sp. larvae, and the root knot nematode Meloidogyne incognita. The bioassay results show that the essential oil of C. regelianus and ascaridole were moderately active against the M. incognita, but strongly effective against both A. aegypti and Artemia sp. larvae.

In vitro and in vivo antiproliferative activity of Calotropis procera stem extracts

The cytotoxic potential of stem organic extracts from Calotropis procera (Asclepiadaceae) was firstly evaluated against cancer cell lines by MTT assay. Subsequently, samples considered cytotoxic were tested for antimitotic activity on sea urchin egg development and for in vivo antiproliferative activity in mice bearing Sarcoma 180 tumor. Among the five extracts (hexane, dichloromethane, ethyl acetate, acetone and methanol), ethyl acetate and acetone extracts displayed higher cytotoxic potential against tumor cells, with IC50 ranging from 0.8 to 4.4 microg/mL, while methanolic extract was weakly cytotoxic. Cytotoxic extracts also exhibited cell division inhibition capacity by antimitotic assay, revealing IC50 values lower than 5 microg/mL. In the in vivo antitumor assessments, ethyl acetate- and acetone-treated animals showed tumor growth inhibition ratios of 64.3 and 53.1%, respectively, with reversible toxic effects on liver and kidneys. Further studies are in progress in order to identify C. procera cytotoxic compound(s) and to understand the mechanism of action responsible for this tumor-decreasing potential.

Analgesic and anti-inflammatory activities of a fraction rich in oncocalyxone A isolated from Auxemma oncocalyx.

In the present work we studied the antinociceptive and antiedematogenic effects of a quinone fraction (QF) isolated from the heartwood of Auxemma oncocalyx Taub. The major constituent of QF, which represented around 80% of this fraction, was a terpenoid quinone named oncocalyxone A (1). Results show that QF (10 and 30 mg/kg body wt., i.p.) significantly inhibited paw edema induced by carrageenan at the second, third, and fourth hours. The effect was dose-dependent and long lasting, and QF was less effective orally. An antiedematogenic effect was also demonstrated in the dextran-induced paw edema. In this model, however, QF was somewhat less potent. QF (1 and 5 mg/kg body wt., i.p.) inhibited acetic acid-induced abdominal contractions in mice in a dose-dependent manner. In addition, QF (5 and 10 mg/kg body wt., i.p.) inhibited only the second phase (inflammatory) in the formalin test, and showed no effect in the hot-plate test in mice. The antinociceptive activity of QF was predominantly peripheral and independent of the opioid system. The observed effects of QF are, at least in part, probably due to the presence of oncocalyxone A (1).

Chemical Composition and Larvicidal Activity of the Essential Oils of Cordia leucomalloides and Cordia curassavica from the Northeast of Brazil

Os oleos essenciais das folhas de Cordia leucomalloides e Cordia curassavica foram obtidos por hidrodestilacao e suas composicoes quimicas determinadas por uma combinacao de CG-EM e CG-DIC. Como resultado, vinte e tres componentes foram identificados em ambos os oleos, representando 98,6 e 91,2% da composicao volatil. O oleo essencial de C. leucomalloides foi caracterizado por uma alta percentagem de sesquiterpenos (90,6%), sendo d-cadineno (17,4%), (E)-cariofileno (15,7%), biciclogermacreno (12,5%) e germacreno D (11,2%) os majoritarios. Por outro lado, o oleo de C. curassavica mostrou proporcoes similares de monoterpenos (47,3%) e sesquitepenos (43,9%), entre os quais a-pineno (20,5%), b-pineno (13,1%), (E)-cariofileno (12,4%) e biciclogermacreno (13,8%) foram os compostos predominantes. O potencial larvicida dos dois oleos foi avaliado contra larvas no terceiro estagio do mosquito Aedes aegypti. Os resultados mostraram que ambos os oleos apresentaram atividade biologica significativa, particularmente o oleo essencial de C. leucomalloides, o qual foi capaz de matar 98,7% das larvas numa concentracao de 100 ppm.

Leaf essential oils of four Piper species from the State of Ceará - Northeast of Brazil

Os oleos essenciais obtidos por hidrodestilacao das folhas de quatro especies de Piper (P. arboreum, P. crassinervium, P. dilatatum and P. tuberculatum), coletadas no estado do Ceara, foram analisados por CG-EM. Os rendimentos dos oleos, calculados sobre o peso do material fresco, variaram entre 0,03 - 0,11% (p/p). Os oleos foram caracterizados pela presenca de mono- e sesquiterpenos, exceto o oleo de P. arboreum, no qual foram identificados apenas sesquiterpenos. b-Elemeno (0,58-3,03%), (E)-cariofileno (2,71-37,78%), germacreno D (3,43-11,81%), biciclogermacreno (2,83-25,07%) e d-cadineno (0,52-2,44%) foram detectados em todas as amostras analisadas. Os monoterpenos majoritarios identificados foram a-pineno (11,27%), b-pineno (20,01%), 1,8-cineol (10,81%) e linalol (28,61%) para P. crassinervium, e a-felandreno (22,53%) e D-3-careno (10,20%) para P. dilatatum. Biciclogermacreno (25,03 e 25,07%) para P. arboreum e P. dilatatum, (E)-nerolidol (11,12%) para P. arboreum, germacreno D (11,81%) para P. tuberculatum e (E)-cariofileno (10,26 e 37,78%) para P. dilatatum e P. tuberculatum, foram os principais sesquiterpenos. Este trabalho descreve, pela primeira vez, a composicao quimica dos oleos essenciais de P. crassinervium e P. tuberculatum.

Constituintes químicos de Lippia sidoides (Cham.) Verbenaceae

Thirteen compounds, 3-O-acetyloleanolic acid (1), methyl 3,4-dihydroxy benzoate (2), lapachenol (3), tecomaquinone (4), tectoquinone (5), tectol (6), acetilated tectol (7), quercetin (8), luteolin (9), glucoluteolin (10), lippisidoquinone (11), taxifolin (12) and isolariciresinol (13), were isolated from ethanol extract of Lippia sidoides. Their structures were assigned unambiguously by a combination of 1D and 2D NMR, IR and EIMS spectral data analysis and comparison with the published data for structurally related compounds. In brazilian traditional medicine the aerial parts of this specie are used as anti-infective agent, particularly as antiseptic.

Pyrrolizidine alkaloids from Heliotropium indicum

Helindicine (1), a new pyrrolizidine alkaloid with unusual structural features, together with the known lycopsamine (2), were isolated from the roots of Heliotropium indicum (Boraginaceae). The structures were established by a combination of 1D and 2D NMR methods (COSY, HMQC, HMBC, and NOESY) and HREIMS. This is the first report of a lactone pyrrolizidine alkaloid in the genus Heliotropium. Compounds 1 and 2 were assayed for antioxidant activity and showed moderate activity.