2 resultados para SNAKE VENOM METALLOPROTEINASE
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
Antiophidic activity from decoct of Jatropha gossypiifolia L. leaves against Bothrops jararaca venom. Snakebites are a serious worldwide public health problem. In Latin America, about 90 % of accidents are attributed to snakes from Bothrops genus. Currently, the main available treatment is the antivenom serum therapy, which has some disadvantages such as inability to neutralize local effects, risk of immunological reactions, high cost and difficult access in some regions. In this context, the search for alternative therapies to treat snakebites is relevant. Jatropha gossypiifolia L., a medicinal plant popularly known in Brazil as “pinhão-roxo”, is very used in folk medicine as antiophidic. So, the aim of this study is to evaluate the antiophidic properties of this species against enzymatic and biological activities from Bothrops jararaca snake venom. The aqueous leaf extract of J. gossypiifolia was prepared by decoction. The inhibition studies were performed in vitro, by pre-incubation of a fixed amount of venom with different amounts of extract from J. gossypiifolia for 60 min at 37 °C, and in vivo, through oral or intraperitoneal treatment of animals, in different doses, 60 min before venom injection. The proteolytic activity upon azocasein was efficiently inhibited, indicating inhibitory action upon metalloproteinases (SVMPs) and/or serine proteases (SVSPs). The extract inhibited the fibrinogenolytic activity, which was also confirmed by zymography, where it was possible to observe that the extract preferentially inhibits fibrinogenolytic enzymes of 26 and 28 kDa. The coagulant activity upon fibrinogen and plasma were significantly inhibited, suggesting an inhibitory action upon thrombin-like enzymes (SVTLEs), as well as upon clotting factor activators toxins. The extract prolonged the activated partial thromboplastin time (aPTT), suggesting an inhibitory action toward not only to SVTLEs, but also against endogenous thrombin. The defibrinogenating activity in vivo was efficiently inhibited by the extract on oral route, confirming the previous results. The local hemorrhagic activity was also significantly inhibited by oral route, indicating an inhibitory action upon SVMPs. The phospholipase activity in vitro was not inhibited. Nevertheless, the edematogenic and myotoxic activities were efficiently inhibited, by oral and intraperitoneal route, which may indicate an inhibitory effect of the extract upon Lys49 phospholipase (PLA2) and/ or SVMPs, or also an anti-inflammatory action against endogenous chemical mediators. Regarding the possible action mechanism, was observed that the extract did not presented proteolytic activity, however, presented protein precipitating action. In addition, the extract showed significant antioxidant activity in different models, which could justify, at least partially, the antiophidic activity presented. The metal chelating action presented by extract could be correlated with SVMPs inhibition, once these enzymes are metal-dependent. The phytochemical analysis revealed the presence of sugars, alkaloids, flavonoids, tannins, terpenes and/or steroids and proteins, from which the flavonoids could be pointed as major compounds, based on chromatographic profile obtained by thin layer chromatography (TLC). In conclusion, the results demonstrate that the J. gossypiifolia leaves decoct present potential antiophidic activity, including action upon snakebite local effects, suggesting that this species may be used as a new source of bioactive molecules against bothropic venom.
Resumo:
OBJECTIVE: The aim of this study was to compare the immunohistochemical expression of nuclear factor κB (NF-κB), matrix metalloproteinase 9 (MMP-9), and CD105 in odontogenic keratocysts (OKCs), dentigerous cysts (DCs), and radicular cysts (RCs). STUDY DESIGN: Twenty cases of OKCs, 20 DCs, and 20 RCs were analyzed. A labeling index (LI), which expresses the percentage of NF-κB-stained nuclei, was calculated for the analysis of NF-κB expression. Expression of MMP-9 in the epithelium and in the capsule of each lesion was scored as 0 (<10% stained cells), 1 (10%-50% stained cells), or 2 (>50% stained cells). In addition, MMP-9 immunostaining was analyzed in endothelial cells of vessels with a conspicuous lumen. The angiogenic index was determined based on the number of anti-CD105 antibody-stained microvessels. RESULTS: In the epithelial component, the NF-κB LI was higher in OKCs than in DCs and RCs (P < .001). Analysis of MMP-9 expression in the epithelial component showed a predominance of score 2 in OKCs (90%), DCs (70%), and RCs (65%; P = .159). Evaluation of the NF-κB LI according to the expression of MMP-9 in the epithelial lining revealed no significant difference between lesions (P = .282). In the fibrous capsule, the highest percentage of MMP-9-stained cells (score 2) was observed in OKCs (P = .100). Analysis of the expression of MMP-9 in the vessels of odontogenic cysts showed a predominance of score 2 in OKCs (80%) and RCs (50%) and of score 1 in DCs (75%; P = .002). Mean microvessel count was high in RCs (16.9), followed by DCs (12.1) and OKCs (10.0; P = .163). No significant difference in microvessel count according to the expression of MMP-9 was observed between groups (P = .689). CONCLUSIONS: The results suggest that the more aggressive biologic behavior of OKCs is related to the higher expression of MMP-9 and NF-κB in those lesions. The differences in the biologic behavior of the lesions studied do not seem to be associated with the angiogenic index.