Fábio de Sousa Menezes

Isoquercitrin isolated from hyptis fasciculata reduces glioblastoma cell proliferation and changes β-catenin cellular localization

Isoquercitrin isolated from the aerial parts of Hyptis fasciculata was evaluated according to its capacity to interfere with glioblastoma (Gbm) cell growth. Gbm cells were incubated with isoquercitrin, quercetin, or rutin at concentrations of 25, 50, and 100 μmol/l for 24, 48, and 72 h. Quercetin and rutin affected Gbm cell proliferation after treatment times of longer than 24 h. However, increasing concentrations of isoquercitrin inhibited 50% of Gbm cell proliferation at 24 h and further reached nearly 90% inhibition at 72 h. This effect did not affect cell morphology, cell viability, or cleaved capase-3 levels, indicating that isoquercitrin did not induce Gbm cell death. A marked reduction in cyclin D1 levels and an increase in p27 levels were observed when 100 μmol/l of isoquercitrin was added to Gbm cells. Interestingly, nuclear &bgr;-catenin staining observed in a subpopulation of untreated Gbm cells was found in the cytoplasm after 100-μmol/l isoquercitrin treatment. Collectively, these data show that isoquercitrin reduces Gbm cell growth without inducing apoptosis, possibly by modulating the control of the cell cycle. Our data also suggest that &bgr;-catenin-mediated signaling may be involved on the antiproliferative activity of isoquercitrin.

Hypoglycemic activity of two Brazilian Bauhinia species: Bauhinia forficata L. and Bauhinia monandra Kurz.

The hypoglycemic activity of aqueous extracts from Bauhinia forficata L. and Bauhinia monandra Kurz leaves (10% w/v) was evaluated in normoglycemic mice. Both extracts have shown hypoglycemic activity using this methodology. It was also possible to isolate two flavonoids from B. forficata L., 3,7-di-O-a-rhamnopyranosylquercetin and 3,7-di-O-a-rhamnopyranosylkaempferol (kaempferitrin), whose structures were elucidated by usual NMR techniques. Only the quercetin derivative was identified in B. monandra aqueous extract by HPLC.

Platelet compatibility of PLGA, chitosan and PLGA-chitosan nanoparticles

AIM The increasing interest in biodegradable nanoparticles containing biomaterials such as poly(D,L-lactide-co-glycolide) (PLGA) and chitosan for drug delivery raises issues regarding the blood compatibility of these nanoparticles, since some nanoparticles, including carbon nanoparticles, can affect human platelet aggregation and cause vascular thrombosis. Therefore, the aim of this work was to investigate the effect of polymeric nanoparticles on human platelet function by measuring aggregation and receptor expression in vitro. MATERIALS & METHOD PLGA, chitosan-PLGA and a series of chitosan nanoparticles were prepared by the single emulsion technique and ionotropic gelation method. The effects of these nanoparticles (0.01-100 microg/ml) on resting platelets, as well as on platelet aggregation and expression of receptors (GPIIb/IIIa and P-selectin) induced by agonists in platelet-rich plasma were examined using light aggregometry and flow cytometry. RESULTS & CONCLUSION All tested nanoparticles at concentrations below 10 microg/ml did not modify platelet aggregation, showing that they may be used for the delivery of active molecules to the bloodstream.

Atividade antimicrobiana dos frutos de Syagrus oleracea e Mauritia vinifera

Palmae species are very interesting by the chemical and pharmacological points of view. Two species belonging to this family were chosen to initiate the chemical and pharmacological approach of their fruits: Syagrus oleracea (Martius) Beccari and Mauritia vinifera Martius, known in Brazil as Guariroba and Buriti, respectively. Those palm species can be found in several regions of Brazil, especially at the northeast and southeast of the country. They have been used in folk medicine to treat some diseases, however no toxicological and pharmacological studies have been done so far. For the two studied fruits, the antimicrobial activity tests were carried out by broth microdilution methodology. The objective of this work was to contribute for the pharmacological study of palm species, evaluating the antimicrobial activity of the extracts obtained from the fruits of S. oleracea and M. vinifera. The assays evaluated ethanol extracts of the epicarp/mesocarp of S. oleracea and epicarp/mesocarp of M. vinifera; hexane extract of the endosperm of S. oleracea; hexane and ethyl acetate fractions of the epicarp/mesocarp of S. oleracea, epicarp/mesocarp of M. vinifera and mesocarp/endocarp of M. vinifera. The lipophilic extracts of S. oleracea obtained the best results for the species. For M. vinifera, the lipophilic partitions have shown a high inhibitory percentage for S. aureus.

Chamaedrydiol, an ursane triterpene from Marsypianthes chamaedrys

A mixture containing a new triterpene, chamaedrydiol (urs-12-ene-2α,3β-diol), and three known triterpenes (lup-20(29)-ene-2α,3β-diol, castanopsol and epigermanidiol) was isolated from Marsypianthes chamaedrys. The components in the mixture were identified using spectroscopic methods. In addition, a mixture of four less polar known triterpenes consisting of α-amyrin, β-amyrin, lupeol and germanicol, was also isolated.

Atividade antioxidante de tinturas vegetais, vendidas em farmácias com manipulação e indicadas para diversos tipos de doenças pela metodologia do DPPH

This work describes the antioxidant evaluation through the DPPH free radical methodology of commercial available tinctures indicated for different diseases and purchased in commercial pharmacies. All of those diseases have always being caused by excess or accumulation of free radicals. It was noteworthy the coherence between the botany family in which the plant of each tincture is inserted as well as its chemical composition with the antioxidant activity observed. In the cases where this statement could not be shown, it was proved by chromatographic methods that the tinctures were not properly prepared or even it constituted a case of adulteration.

Crude ethanol extract from babassu (Orbignya speciosa): cytotoxicity on tumoral and non-tumoral cell lines

Plant-derived substances have been considered as important sources of drugs, including antineoplasic agents. Babassu mesocarp is popularly used in Brazil as a food additive, and in popular medicine against several conditions, such as inflammations, menstrual pains and leukaemia. From babassu Orbignya speciosa (Mart.) Barb. Rodr. [Arecaceae (Palmae)] epicarp/mesocarp, an ethanol extract was prepared and named OSEME, which was tested on the viability,morphology and metabolism of several cell lines, such as the leukaemic cell lines, HL-60, K562 and the latter multidrug resistant counterpart K562-Lucena 1, the human breast cancer cell line MCF-7, the mouse fibroblast cell line 3T3-L1 and fresh human lymphocytes. OSEME promoted a dose-dependent decrease on the viability of all cells. This effect was much more pronounced on the tumoral cell lines than on non-tumoral cells, a phenomenon revealed by the dose of OSEME which promotes half of maximal effect (ID50). The decrease on viability was followed by shrinkage of cells, alteration on their morphology, and a markedly nuclear condensation. Curiously, stimulation of 6-phosphofructokinase activity (6.6-times) was observed on HL-60 cells, treated with OSEME, when compared to control treated with ethanol (vehicle). These results support evidences to suggest OSEME as a promising source of novel antineoplasic agents.

Estudo da utilização de plantas medicinais pela população da Ilha Grande - RJ

Ethnopharmacology has been re-discovered by the end of the XX Century, and beginnings of the XXI Century. Ethnopharmacology has showed a new source for discovery and development of new drugs, if compared with other methods of search (random, chemicosystematic, philogenetics). The great challenge is also redeem the time and preserve popular knowledgement about medical plants1. We realize an ethnopharmacological approach in Ilha Grande, Rio de Janeiro, interviewing local population about their culture and uses of medical plants, and the transmission of this knowledgement for the next generation.

Effects of a nanocomposite containing Orbignya speciosa lipophilic extract on Benign Prostatic Hyperplasia

ETHNOPHARMACOLOGICAL RELEVANCE Lower urinary tract symptoms (LUTS) are a common complaint among aging men and are usually caused by Benign Prostatic Hyperplasia (BPH). A number of medical treatments for LUTS/BPH exist, such as α-blockers, 5α-reductase inhibitors, phytotherapeutical drugs and combination therapies. Babassu is the common name of a Brazilian native palm tree called Orbignya speciosa, whose kernels are commonly used (eaten entirely or as a grounded powder), in parts of Brazil for the treatment of urinary disorders. This study investigates the effects of Orbignya speciosa nanoparticle extract, a newly developed phytotherapic formulation derived from the kernels of babassu, in the treatment of BPH. MATERIALS AND METHODS Orbignya speciosa extract was obtained from the kernels, a nanoparticulate system was developed and acute toxicity test was performed. BPH primary stromal cell and tissue cultures were established and treated with 300μg/mL Orbignya speciosa nanoparticle (NanoOse) extract in order to evaluate its effects on apoptosis induction, cytotoxicity, cell morphology and proliferation. RESULTS Our results indicated that NanoOSE shows no toxicity in animals and acts incisively by promoting morphological cell changes, reducing cell proliferation as well as inducing necrosis/apoptosis on BPH cells and tissues. CONCLUSIONS This study provided the first report of the successful use of NanoOSE on BPH treatment which corroborates with the popular use of the kernels of this plant. The results also suggest the potential of NanoOSE as a candidate new phytotherapeutic agent on the management of BPH.

Enhancement of Insulin Release from the β-Cell Line INS-1 by an Ethanolic Extract of Bauhinia variegata and Its Major Constituent Roseoside

Plants of the genus Bauhinia are used in several countries worldwide for the treatment of diabetes, and several related species have been shown to have hypoglycaemic effects in vivo in both normoglycaemic and alloxan- and streptozotocin-treated animal models. In this study, the insulin-secreting cell line INS-1 was used to examine the effects of the crude ethanolic extract of leaves of B. variegata L. var. Candida Voidt and its major metabolite (6 S,7 E,9 R)-9-hydroxymegastigma-4,7-dien-3-one-9- beta-glycopyraroside (roseoside) on insulinotropic activity. The crude extracts and the major metabolite were shown to increase insulin secretion in a dose-dependant manner.