Organic Synthesis Department (M.S., N.N.), Daiichi Sankyo RD Novare, Co, Ltd, Tokyo, Japan.
Biological Research Laboratories (M.D., H.T., S.H., S.M., K.Y., N.T.), Daiichi Sankyo, Co, Ltd, Tokyo, Japan.
Arterioscler Thromb Vasc Biol. 2021 Jan;41(1):360-376. doi: 10.1161/ATVBAHA.120.314516. Epub 2020 Oct 22.
Enhancement of LCAT (lecithin:cholesterol acyltransferase) activity has possibility to be beneficial for atherosclerosis. To evaluate this concept, we characterized our novel, orally administered, small-molecule LCAT activator DS-8190a, which was created from high-throughput screening and subsequent derivatization. We also focused on its mechanism of LCAT activation and the therapeutic activity with improvement of HDL (high-density lipoprotein) functionality. Approach and Results: DS-8190a activated human and cynomolgus monkey but not mouse LCAT enzymes in vitro. DS-8190a was orally administered to cynomolgus monkeys and dose dependently increased LCAT activity (2.0-fold in 3 mg/kg group on day 7), resulting in HDL cholesterol elevation without drastic changes of non-HDL cholesterol. Atheroprotective effects were then evaluated using × mice fed a Western diet for 8 weeks. DS-8190a treatment achieved significant reduction of atherosclerotic lesion area (48.3% reduction in 10 mg/kg treatment group). Furthermore, we conducted reverse cholesterol transport study using × mice intraperitoneally injected with J774A.1 cells loaded with [H]-cholesterol and confirmed significant increases of [H] count in plasma (1.4-fold) and feces (1.4-fold on day 2 and 1.5-fold on day3) in the DS-8190a-treated group. With regard to the molecular mechanism involved, direct binding of DS-8190a to human LCAT protein was confirmed by 2 different approaches: affinity purification by DS-8190a-immobilized beads and thermal shift assay. In addition, the candidate binding site of DS-8190a in human LCAT protein was identified by photoaffinity labeling.
This study demonstrates the potential of DS-8190a as a novel therapeutic for atherosclerosis. In addition, this compound proves that a small-molecule direct LCAT activator can achieve HDL-C elevation in monkey and reduction of atherosclerotic lesion area with enhanced HDL function in rodent.
增强 LCAT（卵磷脂：胆固醇酰基转移酶）活性有可能对动脉粥样硬化有益。为了评估这一概念，我们对我们新开发的、经口服给予的小分子 LCAT 激活剂 DS-8190a 进行了表征，该化合物是通过高通量筛选和后续衍生化获得的。我们还重点研究了其激活 LCAT 的机制以及改善 HDL（高密度脂蛋白）功能的治疗活性。
DS-8190a 在体外可激活人源和食蟹猴源但不能激活鼠源 LCAT 酶。DS-8190a 经口给予食蟹猴，剂量依赖性地增加 LCAT 活性（第 7 天 3mg/kg 组增加 2.0 倍），导致 HDL 胆固醇升高，而非 HDL 胆固醇无明显变化。然后使用饲喂 8 周西方饮食的 × 小鼠评估了抗动脉粥样硬化作用。DS-8190a 治疗可显著减少动脉粥样硬化病变面积（10mg/kg 治疗组减少 48.3%）。此外，我们使用经腹腔注射 J774A.1 细胞负载 [H]-胆固醇的 × 小鼠进行了胆固醇逆向转运研究，并证实 DS-8190a 治疗组血浆 [H]计数显著增加（第 2 天增加 1.4 倍，第 3 天增加 1.5 倍）和粪便 [H]计数增加（第 2 天增加 1.4 倍，第 3 天增加 1.5 倍）。关于涉及的分子机制，通过 2 种不同方法证实了 DS-8190a 与人 LCAT 蛋白的直接结合：DS-8190a 固定珠的亲和纯化和热位移测定。此外，通过光亲和标记鉴定了 DS-8190a 在人 LCAT 蛋白中的候选结合位点。
本研究证明了 DS-8190a 作为一种新型动脉粥样硬化治疗药物的潜力。此外，该化合物证明了小分子直接 LCAT 激活剂可在猴子中升高 HDL-C，并降低载脂蛋白 E 基因敲除小鼠的动脉粥样硬化病变面积，同时增强 HDL 功能。
