Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia, Brazil.
Departamento de Medicina, Universidade Federal de Rondônia, UNIR, Porto Velho-RO, Brazil.
Curr Top Med Chem. 2019;19(22):1952-1961. doi: 10.2174/1568026619666190725102812.
Several studies have aimed to identify molecules that inhibit the toxic actions of snake venom phospholipases A2 (PLA2s). Studies carried out with PLA2 inhibitors (PLIs) have been shown to be efficient in this assignment.
This work aimed to analyze the interaction of peptides derived from Bothrops atrox PLIγ (atPLIγ) with a PLA2 and to evaluate the ability of these peptides to reduce phospholipase and myotoxic activities.
Peptides were subjected to molecular docking with a homologous Lys49 PLA2 from B. atrox venom modeled by homology. Phospholipase activity neutralization assay was performed with BthTX-II and different ratios of the peptides. A catalytically active and an inactive PLA2 were purified from the B. atrox venom and used together in the in vitro myotoxic activity neutralization experiments with the peptides.
The peptides interacted with amino acids near the PLA2 hydrophobic channel and the loop that would be bound to calcium in Asp49 PLA2. They were able to reduce phospholipase activity and peptides DFCHNV and ATHEE reached the highest reduction levels, being these two peptides the best that also interacted in the in silico experiments. The peptides reduced the myotubes cell damage with a highlight for the DFCHNV peptide, which reduced by about 65%. It has been suggested that myotoxic activity reduction is related to the sites occupied in the PLA2 structure, which could corroborate the results observed in molecular docking.
This study should contribute to the investigation of the potential of PLIs to inhibit the toxic effects of PLA2s.
多项研究旨在寻找能抑制蛇毒磷脂酶 A2(PLA2)毒性的分子。研究表明,PLA2 抑制剂(PLIs)在这方面的效果显著。
本研究旨在分析来源于矛头蝮蛇 PLIγ(atPLIγ)的肽与 PLA2 的相互作用,并评估这些肽降低磷脂酶和肌毒性活性的能力。
采用同源建模的方法,将肽与来自矛头蝮蛇 venom 的同源 Lys49 PLA2 进行分子对接。采用 BthTX-II 及不同比例的肽进行磷脂酶活性中和试验。从矛头蝮蛇 venom 中纯化出有催化活性和无催化活性的 PLA2,并与肽一起进行体外肌毒性活性中和实验。
肽与 PLA2 疏水性通道附近及 Asp49 PLA2 中与钙结合的环上的氨基酸相互作用。它们能够降低磷脂酶活性,肽 DFCHNV 和 ATHEE 达到最高的降低水平,这两种肽在计算机模拟实验中也有相互作用。肽减少了肌管细胞的损伤,其中 DFCHNV 肽的减少程度约为 65%。有人认为肌毒性活性的降低与 PLA2 结构中占据的部位有关,这可以佐证分子对接中观察到的结果。
本研究应有助于研究 PLIs 抑制 PLA2 毒性作用的潜力。