Antinociceptive and anti-inflammatory effects of octacosanol from the leaves of Sabicea grisea var. grisea in mice.

Sabicea species are used in the Amazon for treatment of fever and malaria, which suggests that its chemical constituents may have some effect on pain and inflammation. Phytochemical analysis of the hexane fraction obtained from the crude ethanol extract from Sabicea grisea var. grisea Cham. & Schltdl (Rubiaceae), an endemic plant in Brazil, resulted in the isolation of octacosanol. This study investigated the antinociceptive and anti-inflammatory effects of the octacosanol in different experimental models. The crude ethanolic extract and hexane fraction obtained from the leaves of S. grisea produced an inhibition of acetic acid-induced pain. Moreover, octacosanol isolated from the hexane fraction produced a significant inhibition of pain response elicited by acetic acid. Pre-treatment with yohimbine, an alpha 2-adrenergic receptor antagonist, notably reversed the antinociceptive activity induced by octacosanol in the abdominal constriction test. Furthermore, mice treated with octacosanol did not exhibit any behavioral alteration during the hot plate and rota-rod tests, indicating non-participation of the supraspinal components in the modulation of pain by octacosanol with no motor abnormality. In the formalin test, octacosanol did not inhibit the licking time in first phase (neurogenic pain), but significantly inhibited the licking time in second phase (inflammatory pain) of mice. The anti-inflammatory effect of octacosanol was evaluated using carrageenan-induced pleurisy. The octacosanol significantly reduced the total leukocyte count and neutrophils influx, as well as TNF-α levels in the carrageenan-induced pleurisy. This study revealed that the mechanism responsible for the antinociceptive and anti-inflammatory effects of the octacosanol appears to be partly associated with an inhibition of alpha 2-adrenergic transmission and an inhibition of pathways dependent on pro-inflammatory cytokines. Finally, these results demonstrated that the octacosanol from the leaves of S. grisea possesses antinociceptive and anti-inflammatory activities, which could be of relevance for the pharmacological control of pain and inflammatory processes.

The anti-allergic activity of the acetate fraction of Schinus terebinthifolius leaves in IgE induced mice paw edema and pleurisy.

Schinus is a genus of the Anacardiaceae family and contains Schinus terebinthifolius, the Brazilian pepper tree that is widely used in folk medicine. We investigate the anti-allergic activity of the ethyl acetate fraction of S. terebinthifolius Raddi (ST fraction). HPLC analysis reveled that gallic acid, methyl gallate and 1,2,3,4,6-pentagalloylglucose are the major aromatic components of the fraction. Oral pre-treatment with the ST fraction (100 mg/kg) significantly inhibited paw edema induced by compound 48/80 (100 ng/paw) and to a lesser extent, the allergic paw edema (OVA, 3 microg/paw). The ST fraction (100 and 200 mg/kg) also inhibited the edema induced by histamine (100 microg/paw), preventing mast cell degranulation and, consequently, histamine release in Wistar rat peritoneal mast cells induced by C 48/80 (5 microg/mL). This histamine inhibition was also observed after mast cell pre-treatment with both methyl gallate and 1,2,3,4,6-pentagalloylglucose (100 microg/mL), the isolated compounds from the ethyl acetate fraction. Pre-treatment with the ST fraction (100 mg/kg) significantly inhibited total leukocyte and eosinophil accumulation in pleural cavities 24 h after the intrathoracic injection of OVA (12.5 microg/cavity). This effect was related to the inhibition of CCL11/eotaxin and CCL5/RANTES in pleural lavage fluid. Pre-treatment with this fraction (100 mg/kg) failed to reduce the cell influx that was observed after LPS-injection into pleural cavity (250 ng/cavity). These findings demonstrate the anti-allergic effect of the ST fraction, which includes the inhibition of edema formation and histamine release caused by mast cell degranulation and eosinophil influx into the pleural cavity probably reflected by the decreased levels of chemokines in recovered pleural lavage fluid.

Avaliação da atividade antialérgica de Syzygium cumini (L. ) Skeels / Evaluation of the antiallergic activity of Syzygium cumini (L. ) Skeels

Espécies vegetais são reconhecidas fontes de substâncias com atividade terapêutica. Plantas da família Myrtaceae são amplamente usadas na medicina popular e os gêneros Eugenia e Syzygium estão entre os mais importantes. Porém, existem poucos trabalhos que abordem a atvidade antiinflamatória e/ou antialérgica de extratos e frações obtidos de espécies da família Myrtaceae. Neste estudo, nós demonstramos que o extrato aquoso bruto das folhas da espécie de Syzygium cumini (L.) Skeels (S-C), inibe importantes parâmetros da alergia. Nós demonstramos que a administração oral de S-C inibe o edema de pata induzido por diferentes estímulos como, composto 48/80 (C48/80), ovoalbumina (Ova) em camundongos previamente sensibilizados, histamina, serotonina, mas falhou em inibir o edema induzido por PAF. Foi demonstrado ainda, que o pré-tratamento com o extrato S-C inibe a liberação de histamina por mastócitos estimulados pelo C48/80 e a eosinofilia alérgica em camundongos, este último dado que pode estar relacionado à inibição dos níveis de CCL11/eotaxina e de IL-5. A partir da análise por cromatografia líquida de alta performance (HPLC), nós demonstramos que os componentes majoritários no extrato bruto de S-C são substâncias fenólicas, dentre eles os taninos hidrolisáveis e os flavonóides. Identificamos neste estudo que o período entre os meses de novembro a janeiro, representa a época sazonal que o conteúdo fenólico apresenta melhor efeito biológico. Com o objetivo de tentar esclarecer os mecanismos celulares e/ou moleculares pelos quais esta substância de origem vegetal e seus derivados atuam na reação inflamatória de origem alérgica. Nós investigamos o potencial efeito antialérgico e/ou imunomodulador do tratamento com a fração acetato de etila obtida do extrato aquoso bruto de S-C, sobre diferentes parâmetros da resposta alérgica in vivo, como a formação de edema induzido por diferentes estímulos, o recrutamento e o perfil de diferentes tipos celulares no...