Cisbio Bioassays, Codolet, France (S.B., J.V., N.P., E.T., T.R.); and Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina (T.K.).
Cisbio Bioassays, Codolet, France (S.B., J.V., N.P., E.T., T.R.); and Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina (T.K.)
Mol Pharmacol. 2018 Sep;94(3):992-1006. doi: 10.1124/mol.118.112573. Epub 2018 Jun 28.
This paper discusses the process of determining the activity of candidate molecules targeting Gq-protein activation through G-protein-coupled receptors for possible therapeutic application with two functional assays; calcium release and inositol phosphate metabolism [inositol monophosphate (IP1)]. While both are suitable for detecting ligand activity (screening), differences are seen when these assays are used to quantitatively measure ligand parameters for therapeutic activity. Specifically, responses for Gq-related pathways present different and dissimulating patterns depending on the functional assay used to assess them. To investigate the impact of functional assays on the accuracy of compound pharmacological profiles, five exemplar molecules [partial agonist, antagonist, inverse agonist, positive allosteric modulator (PAM) agonist, and positive -PAM] targeting either muscarinic M1 or ghrelin receptors were tested using two functional assays (calcium release and IP1) and the results were compared with theoretical pharmacological models. The IP1 assay is an equilibrium assay that is able to determine the correct (i.e., internally consistent) pharmacological profiles of all tested compounds. In contrast, the nonequilibrium nature of calcium assays yields misleading classification of most of the tested compounds. Our study suggests that the use of an equilibrium assay, such as IP1, is mandatory for the optimal use of pharmacological models that can both identify mechanisms of action and also convert descriptive-to-predictive data for therapeutic systems. Such assays allow the identification of consistent and simple scales of activity that can guide medicinal chemistry in lead optimization of candidate molecules for therapeutic use.
本文讨论了通过 G 蛋白偶联受体确定靶向 Gq 蛋白激活的候选分子活性的过程，这些候选分子可能具有治疗应用价值，文中使用了两种功能测定法；钙释放和肌醇磷酸盐代谢[肌醇单磷酸 (IP1)]。虽然这两种方法都适用于检测配体活性（筛选），但当这些测定法用于定量测量治疗活性的配体参数时，就会发现差异。具体来说，与 Gq 相关的途径的反应根据用于评估它们的功能测定法而呈现出不同和不同的模式。为了研究功能测定法对化合物药理学特征准确性的影响，使用两种功能测定法（钙释放和 IP1）测试了针对毒蕈碱 M1 或胃饥饿素受体的五种典型分子[部分激动剂、拮抗剂、反向激动剂、正变构调节剂 (PAM) 激动剂和正-PAM]，并将结果与理论药理学模型进行了比较。IP1 测定法是一种平衡测定法，能够确定所有测试化合物的正确（即内部一致）的药理学特征。相比之下，钙测定法的非平衡性质会导致对大多数测试化合物的错误分类。我们的研究表明，使用平衡测定法（如 IP1）是优化能够识别作用机制并将描述性数据转换为治疗系统预测性数据的药理学模型的必要条件。此类测定法可用于确定一致且简单的活性标度，从而指导药物化学对候选分子进行治疗用途的先导优化。
