Kratom alkaloids: in vitro and in vivo pharmacological mechanisms

卡痛生物碱：体外和体内药理机制

• 批准号: 10493516
• 负责人: Christopher R McCurdy
• 金额: $ 7.27万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-15 至 2024-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10493516
• 关键词: Adrenergic Receptor; Alkaloids; Animals; Applications Grants; Behavioral; Binding; Biological; Biological Assay; Brain; Chemicals; Complex; Computer Models; Dose; Drug Kinetics; Drug usage; Enzymes; Female; Gold; Heroin; In Vitro; Individual; Liver; Liver Microsomes; Mediating; Metabolism; Methods; Mitragyna; Natural Products Chemistry; Opioid; Opioid Receptor; Parents; Pathway interactions; Pharmaceutical Preparations; Pharmacodynamics; Pharmacology; Plant Leaves; Plants; Plasma; Rattus; Recombinants; Risk; Self Administration; Source; Stimulus; System; Testing; Toxic effect; Training; Translations; Trees; United States Food and Drug Administration; Urine; abuse liability; antagonist; base; capsule; drug discrimination; in vivo; inhibitor; male; non-opioid analgesic; opioid abuse; pharmacokinetics and pharmacodynamics; receptor; sex

ABTSRACT Mitragyna speciosa (kratom) has exploded onto the US market, with an estimated 55,000 kg entering the US between 2014 and 2016, corresponding to 12 million kratom doses and one million users. The FDA recently used computational modeling to predict that 22 kratom constituents bind to opioid receptors; however, these predictions await translation into whole animals. There is an urgent need for systematic, pharmacological testing of kratom alkaloids to help inform abuse risk. We feel it is important to assess the behavioral effects of not only individual alkaloids, but also alkaloid mixtures representative of plant material in commercially used products. We will extract, isolate, and purify alkaloids from two kratom sources: dried leaf material of Mitragyna speciosa trees and a US commercial product (i.e., OPMS Gold capsules). We will quantify up to ten kratom alkaloids simultaneously using our bioanalytical methods. In a pharmacokinetic-based Aim 1, we will quantify kratom alkaloids in multiple biological matrices (urine, plasma, brain, liver) after p.o. and i.v. administration in rats to obtain a comprehensive ADME profile. Liver microsomes, recombinant CYP450 enzymes, and specific chemical CYP450 inhibitors will be used to identify pathways of metabolism and biologically active metabolites. In our pharmacodynamic-based Aim 2, we will use drug discrimination to identify receptor mechanism(s) underlying abuse-related effects. Four separate groups of rats will be trained to discriminate one of the following: 1) alkaloid mixture in proportion to kratom dried leaf material, 2) alkaloid mixture in proportion to commercially available kratom product (both containing 32 mg/kg mitragynine, 3) 32 mg/kg mitragynine alone, or 4) 3.2 mg/kg 7- hydroxymitragynine alone. Moreover, we will use i.v. drug self-administration to assess abuse risk, and to assess how kratom alkaloids modify the reinforcing effects of abused opioids (i.e., heroin). Male and female rats will be used throughout to assess sex as a biological variable. The overarching hypothesis is that Mitragyna speciosa has a complex pharmacology resulting from multiple alkaloids differentially interacting with both opioid and non- opioid receptors. The following specific hypotheses will be tested: 1) alkaloids interact (i.e., exert synergistic and antagonist effects) with each other and with other abused opioids in drug discrimination and self-administration assays; 2) some of the interactions are due to PK; 3) behavioral effects of the parent alkaloid are due in part to both the parent compound and its behaviorally active metabolites; 4) no single alkaloid accounts for the discriminative stimulus and reinforcing effects of the mixtures; and 5) both opioid and adrenergic receptors mediate the effects of alkaloid mixtures representative of natural plant material. Subtraction and addition of individual alkaloids will help identify the alkaloids most responsible for kratom's integrated pharmacology. After 5 years, we expect to demonstrate that kratom alkaloids exert differential effects through multiple receptor systems, and we further expect to identify key pharmacological mechanisms responsible for the widespread use of kratom.

abtsract Mitragyna Speciosa（Kratom）已爆炸到美国市场，估计有55,000公斤进入美国 在2014年至2016年之间，对应于1200万kratom剂量和100万用户。 FDA最近 使用计算模型来预测22个KRATOM成分与阿片类药物受体结合；但是，这些 预测等待转化为全动物。迫切需要系统的药理测​​试 Kratom生物碱有助于告知滥用风险。我们认为评估不仅要评估行为影响很重要 单个生物碱，但也代表了商业使用产品中植物材料的生物碱混合物。 我们将从两个kratom来源提取，分离和纯化生物碱：Mitragyna Speciosa的干叶材料 树木和美国商业产品（即OPMS金胶囊）。我们将量化多达十个kratom生物碱 同时使用我们的生物分析方法。在基于药代动力学的目标1中，我们将量化kratom P.O的多种生物基质（尿液，血浆，脑，肝脏）中的生物碱。和i.v.大鼠的管理 获得全面的ADME概况。肝微粒体，重组CYP450酶和特定的化学物质 CYP450抑制剂将用于鉴定代谢和生物活性代谢产物的途径。在我们的 基于药效的AIM 2，我们将使用药物歧视来识别受体机制 与滥用有关的效果。将对四组大鼠进行训练以区分以下一组：1）生物碱 与Kratom干叶材料成比例的混合物，2）与市售成比例的生物碱混合物 Kratom产品（均包含32 mg/kg Mitragynine，3）单独使用32 mg/kg mitragynine，或4）3.2 mg/kg 7- 单独的羟基甲酸。此外，我们将使用i.v.药物自我管理以评估滥用风险，并评估 Kratom生物碱如何改变滥用阿片类药物的增强作用（即海洛因）。雄性和雌鼠将 用于评估性别作为生物学变量。总体假设是mitragyna speciosa 具有复杂的药理学，由多种生物碱与阿片类药物和非 - 阿片受体。将测试以下特定假设：1）生物碱相互作用（即发挥协同作用和 拮抗作用）彼此以及其他滥用的阿片类药物在药物歧视和自我管理方面 测定； 2）一些相互作用是由于PK造成的； 3）母体生物碱的行为影响部分是由于 母体化合物及其行为活跃的代谢产物均; 4）没有单一的生物碱说明 混合物的歧视性刺激和增强作用； 5）阿片类药物和肾上腺素能受体 介导代表天然植物材料的生物碱混合物的作用。减法和加法 单个生物碱将有助于确定KRATOM综合药理学最负责的生物碱。后 5年，我们预计将证明Kratom生物碱通过多种受体发挥差异作用 系统，我们进一步期望确定负责广泛使用的关键药理机制 kratom。