Interplay between metabolism and FXR activation in scoparone signaling

scoparone 信号传导中代谢与 FXR 激活之间的相互作用

基本信息

批准号：
8574018
负责人：
Bingfang Yan
金额：
$ 43.75万
依托单位：
UNIVERSITY OF RHODE ISLAND
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-09-01 至 2018-01-15
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8574018
关键词：
Acceleration American Anti-Inflammatory Agents Anti-inflammatory Artemisia Attention Bile Acids Bile fluid Biliary Bilirubin Catalysis Cause of Death Cells Chemosensitization Chenodeoxycholic Acid Chin Chinese Herbs Cholestasis Cholesterol Clinic Coumarins Cytochrome P-450 CYP1A2 Disease Drug Metabolic Detoxication Drug Targeting Enzymes Faculty General Population Genes Genetic Glucuronosyltransferase Health Hepatic Hepatocyte Hepatotoxicity Herb Human Hyperbilirubinemia In Vitro Individual Kidney Diseases Life Liver Liver Dysfunction Liver diseases Marketing Mediating Mentors Metabolic Metabolic Pathway Metabolism Monitor Multi-Drug Resistance Mus North America Organ Pathway interactions Pharmaceutical Preparations Phosphorylation Phosphorylation Inhibition Plasma Play Preparation Proteins Pump Receptor Activation Receptor Signaling Role Sampling Scoparia Signal Transduction Students Testing Therapeutic Toxic effect Training Transgenic Organisms Uridine Diphosphate Uridine Diphosphate Glucuronic Acid Yin alpha benzopyrone bile salts constitutive androstane receptor design drug metabolism experience farnesoid X-activated receptor in vivo liver function mutant promoter receptor response wasting

项目摘要

Scoparone is a coumarin derivative and structurally belongs to the superfamily of polyphenolic compounds. This compound is abundant in Yin Chin (artemisiae scopariae), a Chinese herb that has been used for thousands of years to treat liver and kidney diseases. Yin Chin preparations have received much attention worldwide lately and are marketed as health supplements in North America. Scoparone is recognized as a major hepatic protective compound and has been shown to induce mouse uridine diphosphate-5¿-glucuronosyltransferase-1A1 (UGT1A1), a bilirubin detoxification enzyme. We recently made an effort to test whether scoparone also induces human UGT1A1. Human primary hepatocytes were treated with scoparone or along with chenodeoxycholic acid (CDCA), an activator of the farnesoid X receptor (FXR). To our surprise, scoparone did not induce human UGT1A1, but instead significantly potentiated CDCA in inducing the bile salt export pump (BSEP). This biliary transporter is a target of CDCA-FXR signaling and plays an essential role in the secretion of bile acids. Consistent with the potentiation of BSEP induction, scoparone enhanced CDCA in activating FXR and the enhancement was much reduced with FXR phosphorylation-deficient mutants. In contrast, the enhancement was significantly increased in cells transfected with cytochrome P450 1A2 (CYP1A2), a drug-metabolizing enzyme. The central hypothesis of this project is that scoparone metabolites confer potent hepatic protection against cholestasis by efficaciously modulating FXR phosphorylation. The specific aims are: (1) to determine the potentiation of BSEP induction as a function of scoparone metabolism; (2) to characterize the phosphorylation of FXR by scoparone; and (3) to define the role of the FXR and scoparone metabolism interplay in anti-cholestasis. To determine the metabolism of scoparone in general population, a large number of individual liver samples will be tested for the metabolism of scoparone. The major metabolites will be structurally determined and tested for the potentiation of BSEP induction. To test whether scoparone is a modulator of the phosphorylation of FXR, hepatocytes will be treated with scoparone alone or plus CDCA, and the phosphorylation status of FXR will be analyzed. To ascertain the anti-cholestatic potential of scoparone, mice will be subjected to inducing cholestasis with or without scoparone, and cholestatic markers and the metabolism of scoparone will be monitored. Overall, the proposed studies will establish the metabolic pathway of scoparone and the significance of the metabolism in bile acid elimination. Cholestasis is the most common form of hepatotoxicity, and the scoparone-rich herb Yin Chin has long been used to normalize liver functions. These studies will provide important information on how the hepatic protective activity is achieved. In addition, FXR is recognized as an important metabolic regulator and has anti-inflammatory effect. Interestingly, scoparone has been found to exert these very activities. Thus, a confirmation on the functional connection between FXR and scoparone will have broad mechanistic and therapeutic implications.

茵陈酮是一种香豆素衍生物，在结构上属于多酚化合物超家族，这种化合物在茵陈（蒿）中含量丰富，茵陈是一种中草药，已有数千年的历史，用于治疗肝肾疾病。最近受到全世界的广泛关注，并在北美作为保健补充剂上市，它被认为是一种主要的肝脏保护化合物，并已被证明可以诱导小鼠尿苷二磷酸-5。 -葡萄糖醛酸基转移酶-1A1 (UGT1A1)，一种胆红素解毒酶，我们最近尝试测试 scoparone 是否也诱导人 UGT1A1。用 scoparone 或与法呢醇 X 受体激活剂鹅去氧胆酸 (CDCA) 一起处理人原代肝细胞。 (FXR) 令我们惊讶的是，scoparone 没有诱导人类。 UGT1A1，但相反显着增强了 CDCA 诱导胆汁盐输出泵 (BSEP) 的能力，这种胆汁转运蛋白是 CDCA-FXR 信号传导的目标，并且在胆汁酸的分泌中发挥重要作用，这与 scoparone 的增强作用一致。 CDCA 激活 FXR 的能力增强，并且 FXR 磷酸化缺陷突变体的增强作用大大降低，相反，在转染的细胞中增强作用显着增加。细胞色素 P450 1A2 (CYP1A2)，一种药物代谢酶该项目的中心假设是，scoparone 代谢物通过有效调节 FXR 磷酸化来提供有效的肝脏保护，防止胆汁淤积。具体目标是：(1) 确定 BSEP 的增强作用。诱导作为scoparone代谢的函数；(2)通过以下方式表征FXR的磷酸化： (3) 确定 FXR 和 scoparone 代谢相互作用在抗胆汁淤积中的作用为了确定 scoparone 在一般人群中的代谢，将测试大量个体肝脏样本的 scoparone 代谢。将确定代谢物的结构并测试 BSEP 诱导的增强作用，以测试 scoparone 是否是 FXR、肝细胞磷酸化的调节剂。将单独用scoparone或加CDCA治疗，并且将分析FXR的磷酸化状态，以确定scoparone的抗胆汁淤积潜力，将用或不用scoparone诱导小鼠胆汁淤积，并分析胆汁淤积标记物和scoparone的代谢。总体而言，拟议的研究将确定斯科帕隆的代谢途径以及代谢在胆汁酸消除中的重要性。是最常见的肝毒性形式，富含樟脑酮的草药尹钦长期以来一直被用来使肝功能正常化。此外，FXR 被认为是一种重要的代谢药物。已发现 scoparone 具有这些活性，因此，确认 FXR 和 scoparone 之间的功能联系将具有广泛的机制和治疗意义。