Verdugo Marcelo, Ruiz Encinar Jorge, Costa-Fernández José Manuel, Menendez-Miranda Mario, Bouzas-Ramos Diego, Bravo Manuel, Quiroz Waldo
Instituto de Química, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.
Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, Oviedo, Spain.
PLoS One. 2017 Feb 2;12(2):e0170869. doi: 10.1371/journal.pone.0170869. eCollection 2017.
Antimony is a metalloid that affects biological functions in humans due to a mechanism still not understood. There is no doubt that the toxicity and physicochemical properties of Sb are strongly related with its chemical state. In this paper, the interaction between Sb(III) and Sb(V) with bovine serum albumin (BSA) was investigated in vitro by fluorescence spectroscopy, and circular dichroism (CD) under simulated physiological conditions. Moreover, the coupling of the separation technique, asymmetric flow field-flow fractionation, with elemental mass spectrometry to understand the interaction of Sb(V) and Sb(III) with the BSA was also used. Our results showed a different behaviour of Sb(III) vs. Sb(V) regarding their effects on the interaction with the BSA. The effects in terms of protein aggregates and conformational changes were higher in the presence of Sb(III) compared to Sb(V) which may explain the differences in toxicity between both Sb species in vivo. Obtained results demonstrated the protective effect of GSH that modifies the degree of interaction between the Sb species with BSA. Interestingly, in our experiments it was possible to detect an interaction between BSA and Sb species, which may be related with the presence of labile complex between the Sb and a protein for the first time.
锑是一种类金属，其通过一种仍未被理解的机制影响人体的生物学功能。毫无疑问，锑的毒性和物理化学性质与其化学状态密切相关。本文在模拟生理条件下，通过荧光光谱法和圆二色光谱（CD）体外研究了Sb(III)和Sb(V)与牛血清白蛋白（BSA）之间的相互作用。此外，还采用了分离技术——不对称流场流分级分离与元素质谱联用，以了解Sb(V)和Sb(III)与BSA的相互作用。我们的结果表明，Sb(III)和Sb(V)在与BSA相互作用的影响方面表现出不同的行为。与Sb(V)相比，Sb(III)存在时蛋白质聚集和构象变化方面的影响更大，这可能解释了两种锑物种在体内毒性的差异。所得结果证明了谷胱甘肽（GSH）的保护作用，它改变了锑物种与BSA之间的相互作用程度。有趣的是，在我们的实验中首次检测到BSA与锑物种之间的相互作用，这可能与锑和蛋白质之间存在不稳定络合物有关。
