二氢乳清酸脱氢酶在恶性肿瘤进展中的作用机制研究进展

二氢乳清酸脱氢酶(DHODH)是一种黄素依赖性的代谢酶,在嘧啶代谢从头合成途径中将二氢乳清酸氧化成乳清酸。同时它位于线粒体上,与细胞氧化磷酸化存在紧密联系。此外,DHODH也是铁死亡途径的一个重要抑制因子。本文主要阐述DHODH影响恶性肿瘤进展的内在作用机制,包括其在嘧啶从头合成、氧化磷酸化及铁死亡等方面的重要作用,为DHODH作为恶性肿瘤临床治疗的潜在靶点提供依据。

COX-2/DHODH双重抑制剂存在可行性的初步对接虚拟筛选研究

首次开展了探索环氧合酶-2(COX-2)和二氢乳清酸脱氢酶(DHODH)双重抑制剂存在的可行性研究工作。通过自建COX-2抑制剂数据库,采用虚拟筛选方法,以DHODH的晶体结构为靶标,对自建的COX-2抑制剂数据库进行对接虚拟筛选,筛选出多个对DHODH可能有抑制作用并且具有COX-2抑制活性的分子。研究表明,现有数据库中的25000系列、7000系列、26000系列以及33000系列的抑制剂最有可能成为DHODH和COX-2的双抑制剂,特别是其中的25002、7004和7006这三个抑制剂,具有进一步实验研究的价值。

Novel and potent inhibitors targeting DHODH are broad-spectrum antivirals against RNA viruses including newly-emerged coronavirus SARS-CoV-2

Emerging and re-emerging RNA viruses occasionally cause epidemics and pandemics worldwide,such as the on-going outbreak of the novel coronavirus SARS-CoV-2.Herein,we identified two potent inhibitors of human DHODH,S312 and S416,with favorable drug-likeness and pharmacokinetic profiles,which all showed broad-spectrum antiviral effects against various RNA viruses,including influenza A virus,Zika virus,Ebola virus,and particularly against SARS-CoV-2.Notably,S416 is reported to be the most potent inhibitor so far with an EC5o of 17 nmol/L and an SI value of 10,505.88 in infec-ted cells.Our results are the first to validate that DHODH is an attractive host target through high antiviral efficacy in vivo and low virus replication in DHODH knock-out cells.This work demonstrates that both S312/S416 and old drugs(Leflunomide/Teriflunomide)with dual actions of antiviral and immuno-regulation may have clinical potentials to cure SARS-CoV-2 or other RNA viruses circulating worldwide,no matter such viruses are mutated or not.

老年急性髓系白血病靶向药物的研究进展

急性髓系白血病(AML)是一种损害正常造血的髓系细胞恶性克隆性疾病。年龄、病史、核型和突变特征为急性髓细胞白血病的治疗决策提供了重要的预后信息。AML可以发生于任何年龄段,但以老年人群发病为高峰,65岁以上患者可占总发病人群的50%左右。然而,老年AML患者年龄大、合并症多、耐受性差、ECOG评分高,在选择治疗上存在许多顾虑。在过去的几年里,新药物的出现使癌症治疗发生了革命性变化,有望在AML治疗上取得突破性进展。本文将对二氢乳酸脱氢酶抑制剂、FMS样酪氨酸激酶3抑制剂、B细胞淋巴瘤-2基因抑制剂、异柠檬酸脱氢酶抑制剂和DNA甲基转移酶抑制剂等治疗老年AML的研究进展进行综述。

Design, synthesis, molecular modeling, and biological evaluation of acrylamide derivatives as potent inhibitors of human dihydroorotate dehydrogenase for the treatment of rheumatoid arthritis

Human dihydroorotate dehydrogenase(DHODH) is a viable target for the development of therapeutics to treat cancer and immunological diseases, such as rheumatoid arthritis(RA), psoriasis and multiple sclerosis(MS). Herein, a series of acrylamide-based novel DHODH inhibitors as potential RA treatment agents were designed and synthesized. 2-Acrylamidobenzoic acid analog 11 was identified as the lead compound for structureeactivity relationship(SAR) studies. The replacement of the phenyl group with naphthyl moieties improved inhibitory activity significantly to double-digit nanomolar range.Further structure optimization revealed that an acrylamide with small hydrophobic groups(Me, Cl or Br)at the 2-position was preferred. Moreover, adding a fluoro atom at the 5-position of the benzoic acid enhanced the potency. The optimization efforts led to potent compounds 42 and 53-55 with IC50 values of 41, 44, 32, and 42 nmol/L, respectively. The most potent compound 54 also displayed favorable pharmacokinetic(PK) profiles and encouraging in vivo anti-arthritic effects in a dose-dependent manner.

二氢乳清酸脱氢酶抑制剂抗病毒机制的研究进展

各种病毒的持续暴发提示我们必须准备好广谱抗病毒药物。病毒复制必须通过宿主细胞提供原料,因此靶向宿主抗病毒(Host-targeting antiviral, HTA)药物具有广谱性、前瞻性和低耐药性,其前景广阔。研究发现,宿主二氢乳清酸脱氢酶(Dihydroorotate dehydrogenase, DHODH)是许多急性感染性病毒复制所必需的普遍宿主因子之一。DHODH是一种限速酶,催化嘧啶从头合成途径的第四步反应。因此,它也被开发为许多依赖细胞嘧啶资源疾病的治疗靶点,如自身免疫性疾病、病毒或细菌感染。值得注意的是,DHODH抑制剂(Dihydroorotate dehydrogenase inhibitor, DHODHi)对新型冠状病毒(Severe acute respiratory syndrome coronavirus 2, SARS-CoV-2)也有抑制作用。本文综述了DHODHi抗病毒的原理和抗病毒机制,期待能为DHODHi的开发提供帮助,早日研发出更多广谱抗病毒新药。

A Small-Scale Medication of Leflunomide as a Treatment of COVID-19 in an Open-Label Blank-Controlled Clinical Trial

We recently reported that inhibitors against human dihydroorotate dehydrogenase(DHODH)have broad-spectrum antiviral activities including their inhibitory efficacies on SARS-CoV-2 replication in infected cells.However,there are limited data from clinical studies to prove the application of DHODH inhibitors in Coronavirus disease 2019(COVID-19)patients.In the present study,we evaluated Leflunomide,an approved DHODH inhibitor widely used as a modest immune regulator to treat autoimmune diseases,in treating COVID-19 disease with a small-scale of patients.Cases of 10 laboratory-confirmed COVID-19 patients of moderate type with obvious opacity in the lung were included.Five of the patients were treated with Leflunomide,and another five were treated as blank controls without a placebo.All the patients accepted standard supportive treatment for COVID-19.The patients given Leflunomide had a shorter viral shedding time(median of5 days)than the controls(median of 11 days,P=0.046).The patients given Leflunomide also showed a significant reduction in C-reactive protein levels,indicating that immunopathological inflammation was well controlled.No obvious adverse effects were observed in Leflunomide-treated patients,and they all discharged from the hospital faster than controls.This preliminary study on a small-scale compassionate use of Leflunomide provides clues for further understanding of Leflunomide as a potential antiviral drug against COVID-19.

一类来氟米特类似物二氢乳清酸脱氢酶抑制剂作用模式的理论研究

目的:来氟米特是当今临床上类风湿关节炎疾病治疗中最具有显著病情缓解作用的抗风湿药物之一。本文分析二氢乳清酸脱氢酶(DHODH)与其抑制剂的相互作用模式,以指导新型抗风湿药物的开发。方法:从1D3H晶体结构出发,采用基于配体-受体复合物相互作用的药效团研究方法,建立来氟米特活性代谢物A771726的药效团模型;以晶体中来氟米特活性代谢物A771726为模版,构建42个来氟米特类似物DHODH抑制剂的结构,经结构叠合,采用自组织分子力场分析方法(SOMFA),建立来氟米特活性代谢类似物DHODH抑制剂三维定量构效关系模型;并探讨DHODH与其抑制剂的相互作用模式。结果与结论:建立了合理的来氟米特活性代谢物药效团模型和DHODH抑制剂三维定量构效关系,并且2种方法所得的模型吻合。确定的DHODH与抑制剂的作用模式,可以指导抑制剂的设计,用于开发新型抗风湿药物。

二氢乳清酸脱氢酶作为抗肿瘤靶点的研究进展

二氢乳清酸脱氢酶(dihydroorotate dehydrogenase,DHODH)是存在于线粒体内膜的一种含铁的黄素依赖酶,这种酶催化嘧啶核苷酸从头合成途径的第4步反应。而嘧啶核苷酸可用于DNA、RNA、糖蛋白和磷脂生物合成,对于细胞代谢和细胞增殖至关重要。近年来的研究表明,DHODH与多种肿瘤的发生、发展密切相关,抑制或下调DHODH可以降低肿瘤细胞增殖,诱导其凋亡或者增加其他靶点药物的抗肿瘤效果。该文结合所在实验室目前的研究成果及进展,就DHODH作为治疗恶性肿瘤靶点的相关机制及当前DHODH抑制剂的研究进展作一综述。