Ethyl-2-cyanoacrylate as a sealant after partial cecum resection in rattus norvegicus albinus.

OBJECTIVE: To evaluate the use of ethyl-2-cyanoacrylate in the treatment of an injury caused in a partially excluded segment of the mouse gut: the cecum. METHODS: We used 45 male Wistar rats, divided into three equal groups; in all there was performed a partial resection of the cecum. The groups were designated as Group 1: the lesion was treated with application of ethyl-2-cyanoacrylate, Group 2: suture and application of ethyl-2-cyanoacrylate, Group 3: purse-string suture. The animals were monitored postoperatively and half of each group was necropsied 14 days after the procedure, the remaining on the 28th. They were subjected to macroscopic evaluation, had cecal samples collected for histological examination and the findings were submitted to statistical analysis. RESULTS: Weight gain after the experiment was different among groups (p=0.028). The presence of microabscesses was higher at 28 days postoperatively in group 2 when compared to group 3 (p=0.003). The collagen deposition on the 28th postoperative day was greater in group 1 (p=0.036) and intensity of inflammation at the 14th postoperative day was greater in group 1 (p=0.045). In the other parameters there was no statistical difference. CONCLUSION: The use of ethyl-2-cyanoacrylate was effective in the treatment of cecal stump exclusion of rats as for macroscopic and microscopic findings and postoperative outcome.

Insights of local tissue damage and regeneration induced by BnSP-7, a myotoxin isolated from Bothrops (neuwiedi) pauloensis snake venom.

Envenomations caused by Bothrops snake venoms are characterized by prominent local tissue damage due to myonecrosis, hemorrhage, edema and acute muscle damage which is widely correlated with phospholipases A2 (PLA2). In the present study, the progression of local tissue damage and inflammation induced by BnSP-7, a myotoxin isolated from Bothrops (neuwiedi) pauloensis snake venom, was evaluated. Local tissue damages characterized by edema, necrosis and inflammation were evaluated until 24 h after inoculation of BnSP-7. The regeneration of myofibers, analyzed by light microscopy, was observed from 72 h to 2 weeks post-inoculation of toxin. MMP-2 was expressed in gastrocnemius muscle at all time points tested, while the expression of MMP-9 increased expressively at the same time interval of regenerating muscle, suggesting the involvement of MMP-9 in the regeneration process. The production of pro-inflammatory cytokines was also increased, whereas IL-1 beta showed the highest level. Modification of BnSP-7 with BPB decreased the release of IL-8, IL-6 and IL-1 beta when compared to native BnSP-7. These data suggest that BnSP-7 acts as pro-inflammatory incentives (mediators), inducing MMP and cytokine production from the inflammatory and satellite cells, and thus it may play an important role in inflammatory process and, consequently, in the evolution of local tissue damage and regeneration.

Characterization of inflammatory reaction induced by neuwiedase, a P-I metalloproteinase isolated from Bothrops neuwiedi venom.

The Snake Venom Metalloproteinases (SVMPs) play a relevant role in the multifactorial inflammatory response induced by Bothrops envenomations. Neuwiedase, an SVMP isolated from Bothrops neuwiedi venom, is devoid of hemorrhagic activity on skin tests, but is able to induce myonecrosis and degrade fibrinogen, fibrin, type I collagen, fibronectin and laminin. In this study, we analyzed the inflammatory reaction induced by neuwiedase in gastrocnemius muscle, with special focus on cytokines release. Our results showed clear evidence of inflammatory infiltrate in the gastrocnemius muscle and an increase of MMP-9, and the cytokines KC, IL-1 beta and IL-6 in the early periods after toxin injection. The cytokine release was also evaluated in inflammatory and muscular cell culture. Both murine peritoneal adherent cells (MPACs) and muscle cells (C2C12) released pro-inflammatory cytokines after stimulus with neuwiedase. MPACs showed increased production of KC, IL-1 beta and IL-6 in the cell culture supernatant while in C2C12, the predominant chemokine expressed was KC. These data reinforce the importance of SVMPs in the inflammatory response caused by envenomation and point out the role of muscle cells in this event by releasing pro-inflammatory mediators able to attract leukocytes to the muscle, thus starting and amplifying the setting of the inflammatory reaction.