State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.
State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.
Environ Int. 2020 Mar;136:105423. doi: 10.1016/j.envint.2019.105423. Epub 2020 Feb 5.
Triclosan (TCS), an antimicrobial agent widely used in personal care products and ubiquitously exists in environment, has drawn increasing concern due to its potential to exert multiple adverse effects, ranging from endocrine disruption to carcinogenesis. However, the mechanism of these adverse effects is still not fully elucidated. More and more studies have shown that chemical reactive metabolites (RMs) covalently binding to proteins is a possible reason for these adverse effects, but there is still a lack of appropriate methods to predict or evaluate these adverse effects due to the extremely low abundance of the modified proteins in complex biological samples. In this study, we attempted to address this problem and investigate the possible mechanism of TCS adverse effects by a shotgun proteomics approach based on three-dimensional-liquid chromatography-mass spectrometry (3D-LC-MS). First, the in vitro incubation with model amino acids and protein in microsomes showed that TCS could react with cysteine residue of proteins through 3 types of RMs. Then, a 3D-LC-MS approach was developed to sensitively determine the low abundant modified proteins, which resulted in the identification of 45 TCS-modified proteins, including albumin, haptoglobin and NR1I2, in rats. STRING analysis indicated that these modified proteins mainly were involved in reproductive and development system, endocrine and immune system, and carcinogenesis, which were in accord with the main reported TCS-induced adverse effects and suggested that the covalent modification of TCS RMs for proteins might affect their activities and functions, thus inducing serious adverse effects. This study provided a new insight into the mechanism of TCS adverse effects and may serve as a valuable method to predict or evaluate adverse effects of ubiquitous chemicals.
三氯生（TCS）作为一种广泛应用于个人护理产品的抗菌剂，普遍存在于环境中，由于其具有多种潜在的不良影响，包括内分泌干扰和致癌作用，因此引起了越来越多的关注。然而，这些不良影响的机制尚未完全阐明。越来越多的研究表明，与蛋白质共价结合的化学反应性代谢物（RMs）是这些不良影响的可能原因，但由于复杂生物样品中修饰蛋白的丰度极低，仍然缺乏适当的方法来预测或评估这些不良影响。在这项研究中，我们尝试通过基于三维液相色谱-质谱（3D-LC-MS）的 shotgun 蛋白质组学方法来解决这个问题，并研究 TCS 不良影响的可能机制。首先，通过在微粒体中与模型氨基酸和蛋白质进行体外孵育实验表明，TCS 可以通过 3 种 RMs 与蛋白质中的半胱氨酸残基反应。然后，开发了一种 3D-LC-MS 方法来灵敏地检测低丰度的修饰蛋白，从而在大鼠中鉴定出 45 种 TCS 修饰蛋白，包括白蛋白、触珠蛋白和 NR1I2。STRING 分析表明，这些修饰蛋白主要涉及生殖和发育系统、内分泌和免疫系统以及致癌作用，这与 TCS 诱导的主要不良影响报告一致，并表明 TCS RMs 与蛋白质的共价修饰可能会影响它们的活性和功能，从而导致严重的不良影响。本研究为 TCS 不良影响的机制提供了新的见解，并可能成为预测或评估普遍存在的化学物质不良影响的一种有价值的方法。
