Abstract
Inflammation and haemorrhage are the main characteristics of tissue injury in botropic envenomation. Although some studies have shown that anti-venom prevents systemic reactions, it is not efficient in preventing tissue injury at the site of the bite. Therefore, this work was undertaken to investigate the anti-inflammatory effects of the methanolic extract and fractions from D. elliptica and to evaluate the role of matrix metalloproteinases (MMPs) in this process. Effects of the extract and fractions from D. elliptica were evaluated using a carrageenan-induced paw oedema model in rats, and leukocyte rolling was visualized by intravital. The quantification of MMPs activities (MMP-2 and MMP-9) extracted from the dermis of mice treated with extract and fractions alone or incubated with venom was determined by zymographic analyses. Our results show that intraperitoneal (i.p.) injection of fractions significantly reduced paw oedema after the carrageenan challenge. Treatment with the tannins fraction also resulted in considerable inhibition of the rolling of leukocytes and this fraction was able to decrease the activation of MMP-9. These results confirmed the anti-inflammatory activity of the methanolic extract and tannins fraction of D. elliptica and showed that the dermonecrosis properties of B. jararaca venom might be mediated through the inhibition of MMP-9 activity.
Highlights
Inflammatory reaction and haemorrhage are the main characteristics of tissue injury in botropic envenomation [1]
Our previous study showed that the methanolic extract of Davilla elliptica (125, 250 or 500 mg/kg) given via the oral route failed to reduce paw oedema after the carrageenan test [15]
Polymeric proanthocyanidins are known to have depressing effects on protein digestibility due to their ability to bind and precipitate proteins [16,17]. These factors probably affected the anti-oedematogenic evaluation of this extract administered via the oral route; as shown in Table 1, when we administered the extract of Davilla elliptica via the intraperitoneal route (15.62 and 31.25 mg/kg), oedema was considerably reduced in the first, second, third and fourth hour after the carrageenan administration (p < 0.01), and no significant differences were observed between these doses, the lower dose of this extract (7.81 mg/kg) only inhibited paw oedema at the third hour after administration
Summary
Inflammatory reaction and haemorrhage are the main characteristics of tissue injury in botropic envenomation [1]. Haemorrhage and oedema are consequences of proteolytic action promoted by venom that abolishes the vascular integrity, induces necrosis, promotes the activation of fibroblasts, and stimulates cell recruitment of mononuclear phagocytes and granulocytes to the site of the bite [2] All of these reactions are triggered by venom proteins belonging to a Zn2+-dependent enzyme family known as snake venom metalloproteinases (SVMP) [3]. The aims of the present study were to evaluate the anti-inflammatory action of the methanolic extract and the enriched fractions containing flavonoids and tannins from D. elliptica, as well as to characterize the effect of these fractions on MMP activities against Bothrops jararaca venom inoculation
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
