Advanced search
Start date
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Elevated plasma levels of hepatocyte growth factor in rats experimentally envenomated with Bothrops jararaca venom: Role of snake venom metalloproteases

Full text
Prezoto, B. C. [1] ; Kato, E. E. [2] ; Goncalves, L. R. C. [2] ; Sampaio, S. C. [2] ; Sano-Martins, I. S. [2]
Total Authors: 5
[1] Butantan Inst, Lab Pharmacol, Av Dr Vital Brazil 1500, BR-05503900 Sao Paulo - Brazil
[2] Butantan Inst, Lab Pathophysiol, Av Dr Vital Brazil 1500, BR-05503900 Sao Paulo - Brazil
Total Affiliations: 2
Document type: Journal article
Source: Toxicon; v. 162, p. 9-14, APR 15 2019.
Web of Science Citations: 0

The hepatocyte growth factor (HGF)/c-met pathway, which mainly consists of HGF activator (HGFA) and its substrate HGF, protects various types of cells via anti-apoptotic and anti-inflammatory signals. Thrombin is the main physiological activator of such plasmatic pathway, and increased plasma concentrations of HGF have been considered as a molecular marker for some pathological conditions, such as disseminated intravascular coagulation. Since thrombin generation is often linked to tissue injury, and these events are common during snake venom-induced consumption coagulopathies (VICC), our goals were to examine whether Bothrops jararaca venom (Bjv), which induces VICC in vivo: (i) activates the HGF/c-met pathway in vivo and (ii) cleaves zymogen forms of HGFA and HGF (proHGFA and proHGF, respectively) in vitro. Two experimental groups (n = 6, each) of male adult Wistar rats were subcutaneously injected with 500 mu L of 0.9% NaCl solution (control) or sub-lethal doses (1.6 mg/kg) of Bjv. Three hours after envenomation, whole blood samples were collected from the carotid arteries to evaluate relevant coagulation parameters using rotational thromboelastometry and fibrinogen level (colorimetric assay). Additionally, the plasma concentration of HGF was assayed (ELISA). Thromboelastometric assays showed that blood clotting and fibrin polymerization were severely impaired 3 h after Bjv injection. Total plasma HGF concentrations were almost 6-fold higher in the Bjv-injected group (410.0 +/- 91) compared with control values (68 +/- 18 pg/mL, p < 0.05). Western blotting assay showed that Bjv processed proHGFA and proHGF, generating bands resembling those generated by thrombin and kallikrein, respectively. In contrast to the serine protease inhibitor 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF), the metalloprotease inhibitor ethylenediaminetetraacetic acid disodium salt (Na-2-EDTA) strongly reduced the ability of Bjv to process proHGFA and generated one active band similar to that of thrombin. Since Bjv contains prothrombin and factor X activators, increased intravascular thrombin formation might partly explain the increased HGF levels after bothropic envenomation. In conclusion, these findings suggest that snake venom metalloproteases may be determinant for elevation of plasma levels of HGF in rats experimentally envenomated with Bjv. (AU)

FAPESP's process: 16/00211-0 - Participation of the hepatocyte growth fator pathway in the pathophysiology of experimental envenomation of rats by Bothrops jararaca and Crotalus durissus terrificus venoms
Grantee:Benedito Carlos Prezoto
Support type: Regular Research Grants