Daneshamouz Sana, Saadati Shaghayegh, Zhu Sishi, Kalugin Denis, Shoker Ahmed, Abdelrasoul Amira
Department of Chemical and Biological Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK, S7 N 5 A9, Canada.
Division of Biomedical Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK, S7 N 5 A9, Canada.
Appl Biochem Biotechnol. 2025 May 19. doi: 10.1007/s12010-025-05235-y.
The removal of protein-bound uremic toxins (PBUTs), such as indoxyl sulfate (IS) and indole-3-acetic acid (IAA), from hemodialysis (HD) patients remains a significant challenge due to their strong binding to serum proteins, such as albumin. This study aimed to evaluate the potential of using the enzyme laccase, derived from Trametes versicolor, for the decomposition and removal of IS and IAA during HD. Molecular docking was utilized to investigate the interactions between laccase and the toxins, identifying key functional groups involved. To assess the detoxification efficacy, liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) were employed, allowing for the identification of decomposition byproducts and their toxicity assessment. Additionally, in situ synchrotron radiation micro-computed tomography (SR-µCT) at the Canadian Light Source (CLS) was used to analyze the binding of human serum albumin (HSA) with IS and IAA before and after laccase treatment. Our findings revealed that laccase effectively decomposed IAA into five byproducts, including indole, as confirmed by GC-MS, while IS remained unaffected. The byproducts exhibited lower toxicity ratings than IAA and were more easily eliminated through HD. However, synchrotron-based μ-CT analysis showed reduced HSA-IAA adsorption on the HD membrane post-laccase treatment, with no impact on HSA-IS adsorption. Notably, the transformation of indole into IS in the liver suggests that laccase may not be suitable for IAA detoxification in HD. Despite the lack of expected outcomes, these results provide valuable insights into toxin-enzyme interactions and guide future research toward alternative strategies for PBUTs removal in HD.
从血液透析（HD）患者体内去除与蛋白质结合的尿毒症毒素（PBUTs），如硫酸吲哚酚（IS）和吲哚 - 3 - 乙酸（IAA），仍然是一项重大挑战，因为它们与血清蛋白（如白蛋白）紧密结合。本研究旨在评估源自云芝的漆酶在血液透析过程中分解和去除IS及IAA的潜力。利用分子对接研究漆酶与毒素之间的相互作用，确定其中涉及的关键官能团。为评估解毒效果，采用液相色谱 - 质谱联用（LC - MS）和气相色谱 - 质谱联用（GC - MS）技术，以鉴定分解副产物并评估其毒性。此外，利用加拿大光源（CLS）的原位同步辐射微计算机断层扫描（SR - μCT）分析漆酶处理前后人血清白蛋白（HSA）与IS和IAA的结合情况。我们的研究结果表明，漆酶可有效将IAA分解为五种副产物，包括吲哚，这已通过GC - MS得到证实，而IS则不受影响。这些副产物的毒性评级低于IAA，并且更易于通过血液透析清除。然而，基于同步辐射的μ - CT分析表明，漆酶处理后HD膜上HSA - IAA的吸附减少，而对HSA - IS的吸附没有影响。值得注意的是，吲哚在肝脏中转化为IS表明漆酶可能不适用于血液透析中IAA的解毒。尽管未得到预期结果，但这些结果为毒素 - 酶相互作用提供了有价值的见解，并为未来研究血液透析中去除PBUTs的替代策略提供了指导。
