PDF(Pubmed)
Abstract：
Cristina N. Horak and Yanina A. Assef (2017) P-glycoprotein (P-gp) mediated multixenobiotic resistance (MXR) is a mechanism analogous to multidrug resistance, which has been extensively characterized in mammalian tumours. The expression and function of the MXR mechanism has been demonstrated in numerous aquatic organisms and has been proposed as a biomarker for pollution assessment. A close relationship between thermal stress and MXR response has been reported in some aquatic organisms. Seasonal studies in freshwater organisms are scarce and conducted mainly in zebra mussel (Dreissena polymorpha), whose presence has not been reported in South America. The general purpose of the present study was to evaluate seasonal variation of a biomarker, the MXR mechanism, in the worldwide distributed freshwater snail P. acuta. We analyzed the in situ influence of temperature on the biomarker response over an 18-month field study. MXR defence system was evaluated by a combination of functional assays (RB accumulation) and molecular approaches to analyse P-gp expression. The results demonstrated a linear correlation between MXR response, at activity and expression level, and water temperature at sample site, in P. acuta snails. The characterization of the MXR system in worldwide distributed species, including the study of their seasonal fluctuations, could contribute to the increasing interest to incorporate this biomarker to provide an integrated assessment of mussel health status. This work supports the possible use of P. acuta snails with this purpose and also highlights that the occurrence of variations in MXR response related to water temperature has to be taken into account in the interpretation of in situ monitoring studies.
摘要：
CristinaN.Horak和YaninaA.Assef（2017）P-糖蛋白（P-gp）介导的多生物异源耐药（MXR）是一种类似于多药耐药的机制，在哺乳动物肿瘤中已被广泛表征。MXR机制的表达和功能已在许多水生生物中得到证实，并已被提议作为污染评估的生物标志物。在一些水生生物中，已经报道了热应激与MXR反应之间的密切关系。淡水生物的季节性研究很少，主要在斑马贻贝（Dreissenapolymorpha）中进行，在南美尚未报告其存在。本研究的一般目的是评估生物标志物的季节性变化，MXR机制，在全球分布的淡水蜗牛P.acuta。我们在18个月的现场研究中分析了温度对生物标志物反应的原位影响。通过功能分析(RB积累)和分析P-gp表达的分子方法的组合来评估MXR防御系统。结果表明MXR响应之间存在线性相关性，在活动和表达水平，和样品现场的水温，在P.acuta蜗牛。MXR系统在全球分布物种中的表征，包括研究它们的季节性波动，可能有助于越来越多的兴趣纳入这种生物标志物，以提供贻贝健康状况的综合评估。这项工作支持为此目的可能使用P.acuta蜗牛，并强调在解释原位监测研究时必须考虑与水温相关的MXR响应变化的发生。
