Abstract：
In contrast to small molecules, middle molecules present a promising therapeutic modality owing to their elevated specificity, minimal adverse effects, capacity to target protein-protein interactions, and, unlike antibody-based drugs, their suitability for oral administration and intracellular target engagement. Post-oral administration, the paramount considerations encompass solubility and membrane permeability during the initial phase until the drug attains systemic circulation. Furthermore, penetration of the cell membrane is essential to accessing intracellular targets. We evaluated the solubility and membrane permeability of 965 compounds sourced from middle molecule libraries affiliated with Hokkaido University, Kitasato University, and the University of Tokyo. To gauge membrane permeability, we employed both the parallel artificial membrane permeability assay (PAMPA) and Caco-2 cell monolayers. Notably, while membrane permeability in Caco-2 cells exhibited an approximate threefold increase in comparison to PAMPA measurements, certain compounds demonstrated permeability levels less than one-third of those observed in Caco-2 cells. Recognizing the potential involvement of efflux transporters expressed in Caco-2 cells in these variations, we conducted additional assessments involving directional transport in the presence of a transporter inhibitor. Our findings suggest that nearly 80% of these compounds serve as substrates for efflux transporters. Considering the relevance of intracellular targets, we shifted our focus from membrane permeation to intracellular uptake, conducting simulations tailored to assess cellular uptake.
摘要：
与小分子相比，中间分子由于其特异性的提高，呈现出一种有希望的治疗方式，最小的副作用，靶向蛋白质-蛋白质相互作用的能力，and,与基于抗体的药物不同，它们适合口服给药和细胞内靶标接合。口服后给药，最重要的考虑因素包括在药物达到全身循环之前的初始阶段的溶解度和膜渗透性。此外，细胞膜的穿透对于进入细胞内靶标至关重要。我们评估了来自北海道大学附属中间分子库的965种化合物的溶解度和膜通透性，KitasatoUniversity,和东京大学。要测量膜渗透率，我们采用了平行的人工膜通透性测定（PAMPA）和Caco-2细胞单层。值得注意的是,虽然与PAMPA测量相比，Caco-2细胞的膜通透性显示出大约三倍的增加，某些化合物的通透性水平低于Caco-2细胞中观察到的水平的三分之一。认识到Caco-2细胞中表达的外排转运蛋白在这些变异中的潜在参与，我们进行了额外的评估,涉及转运体抑制剂存在下的定向转运.我们的发现表明，这些化合物中的近80％用作外排转运蛋白的底物。考虑到细胞内靶标的相关性，我们把重点从膜渗透转移到细胞内摄取，进行量身定制的模拟以评估细胞摄取。
