BjussuMP-II, a venom metalloproteinase, induces the release and cleavage of pro-inflammatory cytokines and disrupts human umbilical vein endothelial cells.

ABSTRACT

Snake venom metalloproteases (SVMPs) are hydrolytic enzymes dependent on metal binding, primarily zinc (Zn2+), at their catalytic site. They are classified into three classes (P-I to P-III). BjussuMP-II, a P-I SVMP isolated from Bothrops jararacussu snake venom, has a molecular mass of 24 kDa. It exhibits inhibitory activity on platelet aggregation and hydrolyzes fibrinogen. TNF-α upregulates the expression of adhesion molecules on endothelial cell surfaces, promoting leukocyte adhesion and migration during inflammation. Literature indicates that SVMPs may cleave the TNF-α precursor, possibly due to significant homology between metalloproteases from mammalian extracellular matrix and SVMPs. This study aimed to investigate BjussuMP-II's effects on human umbilical vein endothelial cells (HUVEC), focusing on viability, detachment, adhesion, release, and cleavage of TNF-α, IL-1ß, IL-6, IL-8, and IL-10. HUVEC were incubated with BjussuMP-II (1.5-50 µg/mL) for 3-24 h. Viability was determined using LDH release, MTT metabolization, and 7AAD for membrane integrity. Adhesion and detachment were assessed by incubating cells with BjussuMP-II and staining with Giemsa. Cytokines were quantified in HUVEC supernatants using EIA. TNF-α cleavage was evaluated using supernatants from PMA-stimulated cells or recombinant TNF-α. Results demonstrated BjussuMP-II's proteolytic activity on casein. It was not toxic to HUVEC at any concentration or duration studied but interfered with adhesion and promoted detachment. PMA induced TNF-α release by HUVEC, but this effect was not observed with BjussuMP-II, which cleaved TNF-α. Additionally, BjussuMP-II cleaved IL-1ß, IL-6, and IL-10. These findings suggest that the zinc metalloprotease BjussuMP-II could be a valuable biotechnological tool for treating inflammatory disorders involving cytokine deregulation.