Antioxidants and cardioprotective effects of ethyl acetate fraction of Canavalia rosea leaves in myocardial ischemia-reperfusion injury.

Different degrees in the biological activities of Canavalia rosea had been previously reported . In this study, our group assessed the cardioprotective effects of the ethyl acetate fraction (EAcF) of the Canavalia rosea leaves. Firstly, it was confirmed, by in vitro approach, that the EAcF has high antioxidant properties due to the presence of important secondary metabolites, as flavonoids. In order to explore their potential protector against cardiovascular disorders, hearts were previously perfused with EAcF (300 µg.mL-1) and submitted to the global ischemia followed by reperfusion in Langendorff system. The present findings have demonstrated that EAcF restored the left ventricular developed pressure and decreased the arrhythmias severity index. Furthermore, EAcF significantly increased the glutathiones peroxidase activity with decreased malondialdehyde and creatine kinase levels. EAcF was effective upon neither the superoxide dismutase, glutationes reductase nor the catalase activities. In addition, the Western blot analysis revealed that ischemia-reperfusion injury significantly upregulates caspase 3 protein expression, while EAcF abolishes this effect. These results provide evidence that the EAcF reestablishes the cardiac contractility and prevents arrhythmias; it is suggested that EAcF could be used to reduce injury caused by cardiac reperfusion. However more clinical studies should be performed, before applying it in the clinic.

Phytochemical screening and analgesic profile of the lyophilized aqueous extract obtained from Chrysobalanus icaco leaves in experimental protocols.

CONTEXT: Chrysobalanus icaco L. (Chrysobalanaceae) has been used for the treatment of abdominal pain and cramps. OBJECTIVE: Assess the chemical and pharmacological profile of the lyophilized aqueous extract from C. icaco leaves (AEC). MATERIALS AND METHODS: Chromatographic methods were used to assess compounds from AEC. Mice were treated with vehicle (control group) or AEC (100, 200 or 400 mg/kg, p.o.) (group with 7-8 mice) and the analgesic profile was assessed employing the acetic acid-induced writhing, formalin, hot plate tests and hyperalgesia induced by carrageenan (CG) or tumour necrosis factor-alpha. The animal motor performance was assessed using rota-rod and grip strength tests. RESULTS: The chromatographic profile of AEC demonstrated the presence of terpenoid compounds. The acute pretreatment with AEC, at all doses, produced a significant (p < 0.01) inhibition of painful bahaviour (11.4 ± 3.6; 10.3 ± 2.8; 11.3 ± 2.2) when compared to the control group (24.7 ± 4.7) in acetic acid-induced writhing test. In the formalin test, AEC were effective in the second phase (p < 0.01) (57.2 ± 10.3; 56.3 ± 9.2; 54.7 ± 8.9) when compared to control group (121.9 ± 18.5). No response was observed in the hot plate test. The higher dose of AEC produced a significant (p < 0.01 or p < 0.05) inhibitory effect on the mechanical hyperalgesia test. AEC did not affect the motor performance of the mice. DISCUSSION: The terpenoids from AEC are known for its analgesic and anti-inflammatory properties. So, these results corroborate the experiments using the AEC in inflammatory pain protocols. CONCLUSION: Our results suggest that AEC act against inflammatory pain.

Evaluation of the toxicity and molluscicidal and larvicidal activities of Schinopsis brasiliensis stem bark extract and its fractions

Dengue fever and schistosomiasis are major public health issues for which vector control using larvicide and molluscicide substances present in plants provides a promising strategy. This study evaluated the potential toxicity of the extract of hydroethanol Schinopsis brasiliensis Engl., Anacardiaceae, stem bark and its chloroform, hexane, ethyl acetate, and hydromethanol fractions against Artemia salina and Aedes Aegypti larvae and snails Biomphalaria glabrata. All of the assays were performed in triplicate and the mean mortality rates were used to determine the LC50 and LC90 values using the probit method. The hydroethanol hydromethanol extract and fraction were free of toxicity towards A. salina (LC50 > 1000 µg/ml), while chloroform fraction was moderately toxic (LC50 313 µg/ml); ethyl acetate and hexane fractions displayed low toxicity, with LC50 557 and 582 µg/ml, respectively. Chloroform, hexane, and ethyl acetate fractions showed larvicidal potential towards A. aegypti (LC50 values of 345, 527 and 583 µg/ml, respectively), while chloroform and ethyl acetate fractions were highly toxic to B. glabrata (LC90 values of 68 and 73 µg/ml, respectively). Based on these findings, ethyl acetate, chloroform, and hexane fractions should be further investigated for their potential use against the vectors of dengue and schistosomiasis.

Phytochemical study and antinociceptive effect of the hexanic extract of leaves from Combretum duarteanum and friedelin, a triterpene isolated from the hexanic extract, in orofacial nociceptive protocols

Combretum duarteanum Cambess, Combretaceae, is a plant widely distributed in Northeastern Brazil and, in folk medicine, stems and leaves are used for pain treatment. We investigated the antinociceptive effects of the hexanic extract of leaves from C. duarteanum and of friedelin, its main compound, in formalin-, glutamate- and capsaicin- induced orofacial nociception models. In order to isolate friedelin from the hexanic extract, flash chromatography technique was used. Male mice (n = 8/group) were pretreated with hexanic extract, friedelin, morphine or vehicle, before the injection of algogen agents into the right upper lip (perinasal area). The test of formalin-induced orofacial nociception showed that hexanic extract and friedelin significantly reduced nociception (p < 0.001) in both phases of testing. In the glutamate and capsaicin-induced orofacial nociception tests, pre-treatment with hexanic extract produced a significant reduction of orofacial nociception (p < 0.001) at all doses tested.The results suggest the hexanic extract and friedelin possess antinociceptive effects in models of orofacial nociception in rodents.