Antitumoral and Anticholinesterasic Activities of the Seven Species from Rubiaceae.

BACKGROUND: The genus Psychotria and Palicourea are reported as a source of alkaloids and iridoids, which exhibit biological activities. This study aimed to evaluate antiproliferative and anticholinesterase activities and quantification of the alkaloids of seven species among the genus found in Mato Grosso do Sul region in Brazil. METHODS: Concentrations of alkaloids were measured spectrophotometrically. The extracts were submitted to antiproliferative activity against ten cell lines. The anticholinesterase activity of the extracts was developed using brain structures of male Wistar rats: cerebral cortex, hippocampus, hypothalamus and striatum by the Ellman method. RESULTS: Alkaloids from Psychotria and Palicourea species were quantified which showed values of 47.6 to 21.9 µg/g. Regarding the antiproliferative potential, Palicourea crocea demonstrated selectivity against the 786-0 cell line (GI50: 22.87 µg/mL). Psychotria leiocarpa inhibited cell growth against OVCAR-3 (GI50: 3.28 µg/mL), K-562 (GI50: 5.26 µg/mL), HaCaT (GI50: 27.20 µg/mL), PC-3 (GI50: 34.92 µg/mL), MCF-7 (GI50: 35.80 µg/mL) and P. capillacea showed activity against OVCAR-3 (GI50: 2.33 µg/ml) and U251 (GI50: 16.66 µg/ml). The effect of acetylcholinesterase inhibition was more effective in the hippocampus, demonstrating inhibition for Paliourea crocea, Psychotria deflexa, P. brachybotrya and P. leiocarpa of 70%, 57%, 50% and 40%, respectively, followed by P. poeppigiana and P. capillacea, inhibiting 21%, compared to the control. CONCLUSION: Herein, the present work showed for the first time, anticholinesterasic and antiproliferative activities of extracts of Palicourea and Psychotria seem to be mainly associated with the levels of alkaloids in the leaves of these species.

Anti-inflammatory, Antioxidant and Antiproliferative Activities from Trichilia silvatica (C.DC).

BACKGROUND: Trichilia silvatica, popularly known as "catiguá-branco", is distributed in Brazil (Mato Grosso do Sul), and members of this genus are commonly used for the treatment of rheumatism (arthritis). The aim of this research was to investigate the anti-inflammatory, antioxidant and antiproliferative activities of the methanolic extract of the leaves (MEL-TS) and bark (MEB-TS) of T. silvatica. We also evaluated the concentration of phenolic compounds, flavonoids, flavonol, and condensed tannins by liquid chromatography - photodiode array (LC/PDA) analysis. METHODS: The MEL-TS and MEB-TS revealed the presence of caffeic acid in both extracts by LC/PDA. The samples were evaluated for antioxidant activity using free-radical scavenging and lipoperoxidation assays. The anti-inflammatory effects were studied in carrageenan-induced paw edema, pleurisy and zymosan-induced arthritis. RESULTS: The MEL-TS and MEB-TS showed the total phenolic concentration (270.8 ± 17.10 mg gallic acid equivalents GAE/g extract and 278.8 ± 25.13 mg GAE/ g extract, respectively), and flavonoids in MEL-TS (209.30 ± 2.91 mg quercetin equivalents QE/ g extract). In the lipoperoxidation assay, exhibited moderate antioxidant activity with IC50 values ≤ 35.32 µg/mL. Both extracts inhibited oedema induced by carrageenan at 2 h and 4 h, inhibited leukocyte migration at 6 h post administration, and did not impact zymosan-induced arthritis. Finally, MEL-TS was particularly effective against prostate cell line (GI50 ≤ 0.22 µg/mL). CONCLUSION: Overall, the results indicated that T. silvatica reduce migration leukocytes activity, edema formation in these models of experimental arthritis could explain the popular use for treatment of inflammatory processes (rheumatism).

Floral biology of Tropaeolum majus L. (Tropaeolaceae) and its relation with Astylus variegatus activity (Germar 1824) (Coleoptera: Melyridae)

Tropaeolum majus L. (nasturtium) is a culture popularly known by its medicinal, ornamental and culinary utility. This work aimed to evaluate the interaction between Astylus variegatus (Germar 1824) (Coleoptera: Melyridae) and the nasturtium flowers associated to the weeks of flourishing, in order to conceive the floral mechanims used by the species to attract A. variegatus. The insects collection was achieved with an entomologic net by the sweeping method, during the weekly flowering, at two hours, from 7am to 5pm. The studies of floral biology were carried out in twenty flowers by the analysis of measures and the arrangement of the floral parts. The nasturtium flower offers pollen and nectar to the insect as a compensation. However, it was observed that A. variegatus only collects pollen as a nutritious resource. Tropaeolum majus presents several flowers for each individual and, during the visits, A. variegatus walked throughout the interior of the flower, among the stamens and contacting the ventral region of its body, and while passing through the stigma it lodged the pollen. Sometimes, it uses the internal cavity for sheltering and mating. The visits occurred preferably on the second and fifth weeks of flourishing, with a populational fluctuation between 9am and 11am.

Tropaeolum majus L. (capuchinha) é uma cultura muito conhecida pelo seu valor medicinal, ornamental e culinário. O objetivo do trabalho foi avaliar a interação entre Astylus variegatus (Germar 1824) (Melyridae) com as flores de capuchinha, associado às semanas de florescimento, visando entender os mecanismos florais utilizados pela espécie na atração de A. variegatus. A coleta dos insetos foi realizada com rede entomológica pelo método varredura durante a floração, semanalmente, a cada duas horas, no período de 7 às 17 horas. Os estudos da biologia floral foram realizados em vinte flores, analisando as medidas e disposição das peças florais. A flor de capuchinha oferece ao inseto pólen e néctar como recompensa, contudo, foi observado que A. variegatus coleta apenas pólen como recurso alimentar. Tropaeolum majus apresenta várias flores por indivíduo sendo que durante as visitas A. variegatus caminhava por todo o interior da flor, entre os estames contatando a região ventral de seu corpo e, ao passarem pelo estigma, depositava o pólen. Em alguns momentos, utiliza a cavidade interna para abrigo e acasalamento. As visitas ocorreram preferencialmente na segunda e quinta semanas de florescimento com pico populacional entre as 9 e 11:00h.

Floral biology of Tropaeolum majus L. and its relation with Astylus variegatus activity (Germar 1824).

Tropaeolum majus L. (nasturtium) is a culture popularly known by its medicinal, ornamental and culinary utility. This work aimed to evaluate the interaction between Astylus variegatus (Germar 1824) (Coleoptera: Melyridae) and the nasturtium flowers associated to the weeks of flourishing, in order to conceive the floral mechanims used by the species to attract A. variegatus. The insects collection was achieved with an entomologic net by the sweeping method, during the weekly flowering, at two hours, from 7am to 5pm. The studies of floral biology were carried out in twenty flowers by the analysis of measures and the arrangement of the floral parts. The nasturtium flower offers pollen and nectar to the insect as a compensation. However, it was observed that A. variegatus only collects pollen as a nutritious resource. Tropaeolum majus presents several flowers for each individual and, during the visits, A. variegatus walked throughout the interior of the flower, among the stamens and contacting the ventral region of its body, and while passing through the stigma it lodged the pollen. Sometimes, it uses the internal cavity for sheltering and mating. The visits occurred preferably on the second and fifth weeks of flourishing, with a populational fluctuation between 9am and 11am.