Flavonoids: Promising Natural Products for Treatment of Skin Cancer (Melanoma)

Melanoma, which is the most malignant skin cancer type, has got one of the fastest increasing incidence rates of all cancer types in the world. When belatedly diagnosed, melanoma is extremely invasive and metastatic. Although there are effective drugs used to treat melanoma, some cell lines have proven resistant to chemotherapy. In this context, several research groups on natural products have investigated the anticancer effect of new natural molecules in the treatment of melanoma. Flavonoids have shown to play an important role in chemoprevention and inhibition of the proliferation, migration, and invasion of melanoma cells. In this chapter, we present a systematic review performed through a literature search over a period of 20 years, using specialized databases. Analysis of all selected manuscripts demonstrated that at least 97 flavonoids have already been investigated for the treatment of melanoma using in vitro or in vivo models. Most of the bioactive flavonoids belong to the classes of flavones (38.0%), flavonols (17.5%), or isoflavonoids (17.5%). Apigenin, diosmin, fisetin, luteolin, and quercetin were considered as the most studied flavonoids for melanoma treatment. In general, flavonoids have shown to be a promising source of molecules with great potential for the treatment of melanoma

Amburana cearensis: uma revisão química e farmacológica

Amburana cearensis, conhecida popularmente como “umburana-de-cheiro” ou “cumaru”, é uma planta arbórea amplamente distribuída no Nordeste brasileiro, sua madeira é utilizada na movelaria e tem apreciáveis propriedades terapêuticas na medicina popular. Vários compostos já foram isolados e identificados da A. cearensis, incluindo: ácido protocatecuico, cumarinas, flavonóides (isocampferídeo, campferol, afrormosina, 4’-metoxi-fisetina e quercetina) e glicosídeos fenólicos (amburosídeo A e B), entre outros. Apresenta atividade antiinflamatória, analgésica, antiespasmódica e broncodilatadora. Apesar de sua importância econômica e farmacológica, poucos estudos são encontrados na literatura especializada. Portanto, o presente trabalho buscou fazer uma revisão da química e farmacologia dessa espécie vegetalAmburana cearensis, popularly known as "umburana-de-cheiro" or "cumaru" is a tree widely distributed in northeastern of Brazil, its wood is used in furniture making and has considerable therapeutic properties in folk medicine. Several compounds have been isolated and identified from A. cearensis, including protocatechuic acid, coumarins, flavonoids (isokaempferide, kaempferol, afrormosin and 4’-methoxyfisetin) and the phenol glucosides (amburosides A and B) among others. This species has antiinflammatory, analgesic, antispasmodic and bronchodilator. Despite its economic and pharmacology importance few studies are found in the literature about that species. Therefore, this study attempts to review the chemistry and pharmacology of this plant specie

Volatile constituents and behavioral change induced by Cymbopogon winterianus leaf essential oil in rodents

Cymbopogon winterianus Jowitt (‘Java citronella’) is an important essential oil yielding aromatic grass cultivated in India and Brazil and its volatile essential oils extracted from its leaves are used in perfumery, cosmetics, pharmaceuticals and flavoring industries. However, there is no report on any psychopharmacological study of C. winterianus leaf essential oil (LEO) available to date. In this study, the pharmacological effects of the LEO were investigated in animal models and its phytochemical analyses. GC-MS analysis showed a mixture of monoterpenes, as citronellal (36.19%), geraniol (32.82%) and citronellol (11.37%). LEO exhibited an inhibitory effect on the locomotor activity of mice, an antinociceptive effect by increasing the reaction time in the writhing and capsaicin tests. All doses induced a significant increase in the sleeping time of animals not having modified however, the latency. The LEO did not alter the remaining time of the animals on the rota-rod apparatus. These results suggest a possible central effec

Anti-inflammatory and toxicity studies of atranorin extracted from Cladina kalbii Ahti in rodents

Atranorin (ATR) is the main compound from the lichen Cladina kalbii Ahti, which grows in the arid regions of northeastern Brazil. This study was conducted to evaluate the anti-inflammatory and toxicological properties of ATR. To evaluate anti-inflammatory properties, paw edema was induced by injecting 0.1 mL of carrageenan into the subplantar region of the right hind paw of rats, and leukocyte migration was induced by injection of 500 µL of carrageenan into the peritoneal cavity of mice. In addition, we determined ATR cytotoxicity in L929 cells by MTT assay and acute (5 g/kg-single dose) and subchronic (50 mg/kg-30 days) toxicity tests in Wistar rats. The results showed that ATR (100 mg/kg and 200 mg/kg) exhibited significant anti-inflammatory activity (paw edema and leukocyte migration). In the acute toxicity test, the animals showed hypoactivity and lethargy during the initial period (first 6 hours) and increase in total protein, total and indirect bilirubin, and alkaline phosphatase after 14 days in ATR-treated male rats. The subchronic toxicity test revealed increases in total protein, globulin, gamma-glutamyl transferase, alkaline phosphatase, and total and direct bilirubin in ATR-treated female rats. Histological analysis revealed no changes in the architecture and morphology of the organs. These results suggest that ATR has significant anti-inflammatory activity, with no significant acute and subchronic toxicity or cytotoxicity._________________________________________________________________________________________ RESUMO: Atranorina (ATR) é o principal composto do líquen Cladina kalbii Ahti, que cresce em terras áridas do nordeste brasileiro. Este estudo foi realizado para avaliar as propriedades antiinflamatórias e toxicológicas da ATR. Para avaliar as propriedades antiinflamatórias, o edema de pata foi induzido, administrando-se 0,1 mL de carragenina na região subplantar da pata traseira direita e a migração leucocitária foi induzida pela injeção de 500 µL de carragenina no peritônio. Além disso, determinou-se a citotoxicidade da ATR, utilizando-se a linhagem celular L929, através do teste de MTT e dos testes de toxicidade aguda (5 g/kg - dose única) e subcrônica (50 mg/kg-30 dias) em ratos Wistar. Os resultados mostraram que nas doses de (100 mg/kg e 200 mg/kg) a ATR exibiu atividade antiinflamatória significativa nos ensaios de edema de pata e migração leucocitária. Nos testes de toxicidade aguda, os animais apresentaram hipoatividade e letargia no período inicial (primeiras 6 horas) e aumento das proteínas totais, bilirrubinas total e indireta e fosfatase alcalina depois de 14 dias nos machos tratados. Para o ensaio subcrônico, houve aumento das proteínas totais, gama-glutamil-transferase, fosfatase alcalina e bilirrubina total e direta nas fêmeas tratadas com ATR. Não foram encontradas alterações na arquitetura e morfologia das lâminas histológicas observadas. Esses resultados sugerem que a ATR apresenta atividade antiinflamatória significativa, sem apresentar significativa toxicidade aguda, subcrônica e citotoxicidade