Metabolic Activation and Covalent Protein Binding of Berberrubine: Insight into the Underlying Mechanism Related to Its Hepatotoxicity.
Metabolic Activation and Covalent Protein Binding of Berberrubine: Insight into the Underlying Mechanism Related to Its Hepatotoxicity.
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小檗红素的代谢激活和共价蛋白结合：深入了解与其肝毒性相关的潜在机制
DOI：
10.2147/dddt.s274627
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Qiu F
中科院分区：
文献类型：
--
作者：
Wang K;Rao J;Zhang T;Gao Q;Zhang J;Guang C;Ding L;Qiu F
小檗碱（Berberrubine， BRB）是一种异喹啉类生物碱，是药用植物黄连（Coptis chinensis Franch）或黄柏（Phellodendron chinense Schneid）的主要成分。BRB具有多种药理活性，而暴露于BRB可能对实验动物造成毒性。在本研究中，我们深入研究了BRB对小鼠和大鼠的肝损伤。为了探索其潜在的机制，我们对BRB的代谢激活进行了研究。此外，通过穷尽蛋白水解消化方法，在暴露于BRB后的动物肝脏匀浆样品中观察到蛋白质半胱氨酸残基的共价修饰。基于ALT和AST的生化指标表明，BRB诱导的肝毒性具有时间和剂量依赖性，H&E染色组织病理学检查显示，单剂量100 mg/kg BRB腹腔注射后小鼠肝脏出现明显水肿。在灌胃6周后，给予相同剂量的BRB也观察到轻微的肝毒性。结果，在用GSH作为诱捕剂强化BRB的微粒体孵育过程中，检测到来自BRB反应性代谢物的四种GSH加合物。此外，在肝脏中发现了四种由BBR的亲电代谢物与蛋白质反应产生的cys基加合物。这些结果表明，BRB代谢激活产生的蛋白质加合物的形成可能是BRB诱导毒性机制的关键因素。
Berberrubine (BRB), an isoquinoline alkaloid, is a major constituent of medicinal plants Coptis chinensis Franch or Phellodendron chinense Schneid. BRB exhibits various pharmacological activities, whereas exposure to BRB may cause toxicity in experimental animals. In this study, we thoroughly investigated the liver injury induced by BRB in mice and rats. To explore the underlying mechanism, a study of the metabolic activation of BRB was conducted. Furthermore, covalent modifications of cysteine residues of proteins were observed in liver homogenate samples of animals after exposure to BRB, by application of an exhaustive proteolytic digestion method. It was demonstrated that BRB-induced hepatotoxicities in a time- and dose-dependent manner, based on the biochemical parameters ALT and AST. H&E stained histopathological examination showed the occurrence of obvious edema in liver of mice after intraperitoneal (i.p.) administration of BRB at a single dose of 100 mg/kg. Slight hepatotoxicity was also observed in rats given the same doses of BRB after six weeks of gavage. As a result, four GSH adducts derived from reactive metabolites of BRB were detected in microsomal incubations with BRB fortified with GSH as a trapping agent. Moreover, four cys-based adducts derived from reaction of electrophilic metabolites of BBR with proteins were found in livers. These results suggested that the formation of protein adducts originating from metabolic activation of BRB could be a crucial factor of the mechanism of BRB-induced toxicities.