ATDC5来源外泌体包载小分子药物5Z-7-Oxozeaenol治疗骨关节炎

骨关节炎(osteoarthritis, OA)是一种常见的退行性关节疾病。研究表明,TAK1的抑制剂小分子药物5Z-7-Oxozeaenol(5Z-7),用于治疗OA时直接将药物进行频繁关节腔注射,药物的治疗效果有限。本研究选取小鼠胚胎瘤成软骨细胞系(ATDC5),是一种理想的成软骨细胞模型,其增殖速度和培养稳定性均优于间充质干细胞,用于提取外泌体作为药物的载体。本研究提取ATDC5来源的外泌体(ATDC5-Exos),包载药物5Z-7。在炎性细胞因子诱导大鼠软骨细胞模型中,载药外泌体可以促进合成代谢相关基因Col2a1、Sox9的表达,抑制分解代谢相关基因Adamts5、Mmp13的表达。本研究使用8周龄雄性小鼠,行前交叉韧带离断术(ACLT)诱导OA小鼠模型,关节腔注射外泌体或载药外泌体治疗,取膝关节石蜡切片进行组织学评估。结果显示,载药外泌体可缓解创伤后OA模型的病理表型。结合Micro-CT影像学结果显示,治疗能改善ACLT术后膝关节软骨下骨骨小梁的流失和骨赘减少,关节表面更为光滑。本研究证实,ATDC5-Exos包载药物5Z-7在体内和体外实验中均可缓解OA表型。外泌体包载...     

聚乙二醇修饰小分子药物的研究进展

以高聚物作为载体,携带各种活性化合物组成药物释放系统,在现代医疗中发挥了巨大的作用。高分子偶联物不仅可以改变药物的药动学特征,还可以通过偶联特异性的物质使药物具有主动靶向性。目前研究最广泛的高分子载体是聚乙二醇。聚乙二醇通过与肽链、抗体、酶等活性化合物偶联,可以提高药物溶解度,延长循环半衰期,减少非特异性摄取,增加靶向性。已有很多聚乙二醇修饰的药物上市,也有很多尚处于临床研究阶段。大部分聚乙二醇化药物的临床研究表明,聚乙二醇修饰的药物确实可以提高药效、降低毒副作用。但关于聚乙二醇修饰小分子药物的设计依然需要进一步研究和完善。我们主要讨论聚乙二醇修饰小分子药物的设计和应用。     

小分子药物靶标寻找方法研究进展

许多微生物的次生代谢物属于小分子活性化合物,在医疗及农业领域发挥着重要的作用。在基因组学、蛋白质组学与生物信息学等技术的推动下,一些新的小分子药物靶标寻找方法应运而生了,这些新的方法主要是基于细胞中基因或蛋白质的表达量、蛋白质的亲和性、稳定性等各种特性进行靶标寻找的。小分子药物靶标寻找方法的发展加快了阐明小分子药物作用机理的历程,也为发现新的靶标资源以便于进一步筛选活性更高的药物提供了技术保障。     

不同研发阶段的骨关节炎治疗药物开发进展

骨关节炎是常见的退行性关节疾病,在老年人群中发病率较高。尽管已有一些药物可用于缓解骨关节炎导致的疼痛,但现已上市的药物在骨关节炎治疗上的效果有限,且存在一定程度的不良反应,使骨关节炎在临床治疗上无法达到十分满意的效果。对此,国内外对用于骨关节炎的化学药、生物药、中药的治疗研发进行了诸多探索,这些研发为改善骨关节治疗的效果带来了新希望。本文对骨关节炎治疗用药的研发进展进行综述,尤其是对已进入临床研究阶段的骨关节炎治疗用化学药、生物药研究进展进行了比较分析,以期为相关研发人员提供启示。     

发现靶向蛋白质间相互作用的小分子药物研究进展

蛋白质-蛋白质相互作用在多种细胞功能中具有重要的作用。靶向蛋白质-蛋白质相互作用已经成为新药发现的重要策略,但发现能阻断蛋白质-蛋白质相互作用的小分子药物是一个巨大的挑战。尽管如此,近年来人们还是发现了许多能调控蛋白质-蛋白质相互作用的小分子。该文主要总结了在病毒进入、细胞凋亡通路和神经退行性疾病等方面的蛋白质-蛋白质相互作用小分子抑制剂的研究进展。     

靶向多胺代谢调控网络的小分子药物及抗肿瘤应用

多胺代谢调控网络包括多胺的生物合成、分解代谢和膜转运,作为生物体重要而复杂的生化单元,广泛参与机体细胞的生长、增殖、凋亡和基因表达等活动。多胺代谢调控网络的失衡与多种疾病相关,例如肿瘤、炎症和心血管疾病等。2018年全球癌症统计数据预计,癌症将成为21世纪几乎每个国家或地区人口死亡的主要原因。因此,癌症的预防和治疗将越来越重要。鉴于多胺与肿瘤的发生发展密切相关,本文围绕多胺代谢调控网络,总结了该调控网络作为抗肿瘤治疗靶位的研究现状,同时列举几种代谢酶和转运蛋白质的小分子调节剂,并阐述其靶点作用方式和在肿瘤预防与治疗方面的应用,以期能为靶向多胺代谢调控网络的药物研发以及相关疾病的治疗提供参考。     

应用平衡透析法分析药物小分子与蛋白质相互作用

蛋白质的相关信息一直是生命科学研究的重点,其中药物小分子与蛋白质的相互作用成为近年来的研究热点。平衡透析法是研究药物小分子与蛋白质相互作用的经典方法,通过该方法可以定量的讨论药物小分子与蛋白质结合的结合数量、结合常数。就平衡透析法用于分析药物小分子与蛋白质的作用方式、作用模型及国内外研究进展进行综述。     

胆固醇代谢重编程在胰腺癌中的作用及靶向胆固醇代谢药物的应用

胰腺癌起病隐匿,缺乏有效的治疗方法,是预后最差的实体肿瘤之一,亟需探索新的治疗方向。代谢重编程是肿瘤的重要标志之一,处于恶劣肿瘤微环境中的胰腺癌细胞为了维持旺盛的代谢需求将胆固醇代谢全面上调,肿瘤相关成纤维细胞为癌细胞提供大量的脂质。胆固醇代谢重编程涉及胆固醇的合成、摄取、酯化、以及胆固醇相关代谢产物的一系列调整,与胰腺癌的增殖、侵袭、转移、耐药、免疫抑制等表型密切相关,抑制胆固醇代谢具有明显的抗肿瘤作用。本文从胰腺癌的高危因素、肿瘤相关成纤维细胞与癌细胞间的能量交互、细胞胆固醇代谢关键靶点的作用机制及其靶向药物,综述了胰腺癌胆固醇代谢的复杂性与重要性。胆固醇代谢具有严格的调控与反馈机制,单一靶点药物在临床应用中的效果并不明确,因此胆固醇代谢的多靶点疗法是胰腺癌治疗的新方向。     

微生物细胞色素P450与胆固醇的生物代谢

细胞色素P450(CYP450)是一类含亚铁血红素的单加氧酶,广泛存在于各类生物体内,参与多种外源物质的代谢和内源物质的转化,如甾类激素、胆汁酸、胆固醇等的代谢。胆固醇是一种环戊烷多氢菲的衍生物,也是人类重要的脂类物质和许多特殊生物活性物质的前体之一,当其过量时会导致高胆固醇血症、动脉粥样硬化、静脉血栓生成等,对机体产生不利的影响。微生物CYP450酶可催化胆固醇的生物代谢,特别是其中的CYP125酶是胆固醇分解代谢起始的关键酶,可用作调节胆固醇代谢的药物靶标。     

双刃剑:自噬与肿瘤发生发展的关系及相关靶点小分子药物研究进展

自噬是哺乳动物细胞内重要且复杂的生理活动,同样影响着肿瘤的发生与进展.随着抗肿瘤药物的广泛使用,肿瘤耐药问题日益突出,影响患者预后.多年研究显示,肿瘤自噬与耐药密切相关.目前,已有越来越多的自噬相关小分子药物被用来调节肿瘤自噬活动,以求其能被广泛运用于抗癌方案之中.该文将针对自噬在癌症发生发展过程中的分子机制及相关小分...     

受体相互作用蛋白质激酶3通过上调整合素β3促进骨关节炎相关病变

骨关节炎（osteoarthritis,OA）是最常见的慢性致残性关节疾患,目前尚无针对病因的有效治疗手段。程序性坏死在多种疾病中扮演关键角色,受体相互作用蛋白质激酶3（receptor-interacting protein kinase 3, RIP3）是程序性坏死进程的关键调控因子。有研究显示,RIP3在人与鼠骨关节炎退变软骨组织中表达水平显著上调,提示程序性坏死的发生,但RIP3在软骨中的具体病生理角色仍不明确。本研究拟对过表达RIP3前后的软骨细胞转录物组进行测序分析,探索RIP3在骨关节炎进程中发挥作用的具体机制。RNA测序结果显示,RIP3的过表达诱发软骨细胞中244个基因表达上调,277个表达下调。通过进一步构建基因间共表达作用网络,筛选出16个候选靶基因在mRNA水平进行验证,证实RIP3对磷脂酰肌醇3激酶调节亚单位5（phosphoinositide-3-kinase, regulatory subunit 5,Pik3r5）、整合素β3（integrin subunit beta 3,Itgb3）及成髓细胞瘤转录因子第2亚型（MYB proto-oncogene like 2,Mybl2）的表达上调作用最为显著。CCK-8以及乳酸脱氢酶活性检测结果表明,利用siRNA沉默Itgb3的表达可显著抑制RIP3诱发的软骨细胞活力下降及程序性坏死,同时也抑制了RIP3对软骨细胞中分解代谢相关基因Mmp1、Mmp13与Il6的表达上调作用,以及其对合成代谢相关基因Acan、Col2a1与Sox9的下调作用。本研究证实,RIP3通过上调软骨细胞中Itgb3的表达诱发软骨细胞坏死与软骨基质代谢紊乱,并最终导致软骨退变,为骨关节炎的临床治疗提供了新靶点,同时进一步明确了程序性坏死的病理生理学意义。     

植物小分子肽的研究进展

植物信号肽的研究主要集中在小分子肽.小分子肽作为胞间通讯的关键成分,主要参与信号干扰、反应途径、显示抗菌活性,并以配体的形式与细胞膜表面的受体激酶相互作用,从而实现细胞之间的信号交流.小分子肽是重要的胞间信号感应分子,在植物的不同器官组织、发育阶段主要参与调节植物的生长发育过程和应答生物和非生物胁迫的应激反应,以协调和...     

野生型p53基因对内皮细胞细胞间粘附分子-1表达的影响

细胞间粘附分子－１（ＩＣＡＭ－１）是介导白细胞与内皮细胞粘附的重要粘附分子．为研究野生型ｐ５３基因对内皮细胞ＩＣＡＭ－１表达的影响,分别采用流式细胞术和ＲＴ－ＰＣＲ／ＨＰＬＣ方法测定ＩＣＡＭ－１蛋白及ｍＲＮＡ水平．静息状态的内皮细胞表面结构性地表达有少量的ＩＣＡＭ－１,在肿瘤坏死因子α（ＴＮＦα,１０～１０００Ｕ／ｍｌ）诱导下,其表达呈剂量依赖性增加．将ｐ５３基因导入内皮细胞,则显著抑制ＴＮＦα诱导的内皮细胞表面ＩＣＡＭ－１的表达．ｐ５３基因的导入对静息状态内皮细胞表面结构性表达的ＩＣＡＭ－１影响较小．ｐ５３基因主要通过降低ＩＣＡＭ－１的ｍＲＮＡ水平而抑制内皮细胞表面ＩＣＡＭ－１的表达,但对蛋白的抑制程度小于对ｍＲＮＡ的抑制程度．提示：ｐ５３基因对内皮细胞ＩＣＡＭ－１表达的影响除转录水平控制外,还存在转录后水平的调控     

Identification of Small Molecule Inhibitors of Jumonji AT-rich Interactive Domain 1B (JARID1B) Histone Demethylase by a Sensitive High Throughput Screen

JARID1B (also known as KDM5B or PLU1) is a member of the JARID1 family of histone lysine demethylases responsible for the demethylation of trimethylated lysine 27 in histone H3 (H3K4me3), a mark for actively transcribed genes. JARID1B is overexpressed in several cancers, including breast cancer, prostate cancer, and lung cancer. In addition, JARID1B is required for mammary tumor formation in syngeneic or xenograft mouse models. JARID1B-expressing melanoma cells are associated with increased self-renewal character. Therefore, JARID1B represents an attractive target for cancer therapy. Here we characterized JARID1B using a homogeneous luminescence-based demethylase assay. We then conducted a high throughput screen of over 15,000 small molecules to identify inhibitors of JARID1B. From this screen, we identified several known JmjC histone demethylase inhibitors, including 2,4-pyridinedicarboxylic acid and catechols. More importantly, we identified several novel inhibitors, including 2-4(4-methylphenyl)-1,2-benzisothiazol-3(2H)-one (PBIT), which inhibits JARID1B with an IC₅₀ of about 3 μm in vitro. Consistent with this, PBIT treatment inhibited removal of H3K4me3 by JARID1B in cells. Furthermore, this compound inhibited proliferation of cells expressing higher levels of JARID1B. These results suggest that this novel small molecule inhibitor is a lead compound that can be further optimized for cancer therapy.     

The Oxidative Inactivation of Tissue Inhibitor of Metalloproteinase-1 (TIMP-1) by Hypochlorous Acid (HOCl) is Suppressed by Anti-Rheumatic Drugs

Tissue inhibitors of metalloproteinases (TIMPs) prevent uncontrolled connective tissue destruction by limiting the activity of matrix metalloproteinases (MMPs). That TIMPs should be susceptible to oxidative inactivation is suggested by their complex tertiary structure which is dependent upon 6 disulphide bonds. We examined the oxidative inactivation of human recombinant TIMP-1 (hr TIMP-1) by HOCl and the inhibition of this process by anti-rheumatic agents.

TIMP-1 was exposed to HOCl in the presence of a variety of disease modifying anti-rheumatic drugs. TIMP-1 activity was measured by its ability to inhibit BC1 collagenase activity as measured by a fluorimetric assay using the synthetic pEptide substrate (DNP-Pro-Leu-Ala-Leu-Trp-Ala-Arg), best cleaved by MMP-1.

The neutrophil derived oxidant HOCl, but not the derived oxidant N-chlorotaurine, can inactivate TIMP-1 at concentrations achieved at sites of inflammation. Anti-rheumatic drugs have the ability to protect hrTIMP-1 from inactivation by HOCl. For D-penicil-lamine, this effect occurs at plasma levels achieved with patients taking the drug but for other anti-rheumatic drugs tested this occurs at relatively high concentrations that are unlikely to be achieved in vivo, except possibly in a microenvironment. These results are in keeping with the concept that biologically derived oxidants can potentiate tissue damage by inactivating key but susceptible protein inhibitors such as TIMP-1 which form the major local defence against MMP induced tissue breakdown.     

Procollagen C-endopeptidase Enhancer Protein 2 (PCPE2) Reduces Atherosclerosis in Mice by Enhancing Scavenger Receptor Class B1 (SR-BI)-mediated High-density Lipoprotein (HDL)-Cholesteryl Ester Uptake

Studies in human populations have shown a significant correlation between procollagen C-endopeptidase enhancer protein 2 (PCPE2) single nucleotide polymorphisms and plasma HDL cholesterol concentrations. PCPE2, a 52-kDa glycoprotein located in the extracellular matrix, enhances the cleavage of C-terminal procollagen by bone morphogenetic protein 1 (BMP1). Our studies here focused on investigating the basis for the elevated concentration of enlarged plasma HDL in PCPE2-deficient mice to determine whether they protected against diet-induced atherosclerosis. PCPE2-deficient mice were crossed with LDL receptor-deficient mice to obtain LDLr^−/−, PCPE2^−/− mice, which had elevated HDL levels compared with LDLr^−/− mice with similar LDL concentrations. We found that LDLr^−/−, PCPE2^−/− mice had significantly more neutral lipid and CD68+ infiltration in the aortic root than LDLr^−/− mice. Surprisingly, in light of their elevated HDL levels, the extent of aortic lipid deposition in LDLr^−/−, PCPE2^−/− mice was similar to that reported for LDLr^−/−, apoA-I^−/− mice, which lack any apoA-I/HDL. Furthermore, LDLr^−/−, PCPE2^−/− mice had reduced HDL apoA-I fractional clearance and macrophage to fecal reverse cholesterol transport rates compared with LDLr^−/− mice, despite a 2-fold increase in liver SR-BI expression. PCPE2 was shown to enhance SR-BI function by increasing the rate of HDL-associated cholesteryl ester uptake, possibly by optimizing SR-BI localization and/or conformation. We conclude that PCPE2 is atheroprotective and an important component of the reverse cholesterol transport HDL system.     

microRNA-206 is required for osteoarthritis development through its effect on apoptosis and autophagy of articular chondrocytes via modulating the phosphoinositide 3-kinase/protein kinase B-mTOR pathway by targeting insulin-like growth factor-1

microRNA (miR) has been shown to be involved in the treatment of diseases such as osteoarthritis (OA). This study aims to investigate the role of miR-206 in regulating insulin-like growth factor-1 (IGF-1) in chondrocyte autophagy and apoptosis in an OA rat model via the phosphoinositide 3-kinase (P13K)/protein kinase B (AKT)-mechanistic target of rapamycin (mTOR) signaling pathway. Wistar rats were used to establish the OA rat model, followed by the observation of histopathological changes, Mankin score, and the detection of IGF-1-positive expression and tissue apoptosis. The underlying regulatory mechanisms of miR-206 were analyzed in concert with treatment by an miR-206 mimic, an miR-206 inhibitor, or small interfering RNA against IGF-1 in chondrocytes isolated from OA rats. Then, the expression of miR-206, IGF-1, and related factors in the signaling pathway, cell cycle, and apoptosis, as well as inflammatory factors, were determined. Subsequently, chondrocyte proliferation, cell cycle distribution, apoptosis, autophagy, and autolysosome were measured. OA articular cartilage tissue exhibited a higher Mankin score, promoted cell apoptotic rate, increased expression of IGF-1, Beclin1, light chain 3 (LC3), Unc-51-like autophagy activating kinase 1 (ULK1), autophagy-related 5 (Atg5), caspase-3, and Bax, yet exhibited decreased expression of miR-206, P13K, AKT, mTOR, and Bcl-2. Besides, miR-206 downregulated the expression of IGF-1 and activated the P13K/AKT signaling pathway. Moreover, miR-206 overexpression and IGF-1 silencing inhibited the interleukins levels (IL-6, IL-17, and IL-18), cell apoptotic rate, the formation of autolysosome, and cell autophagy while promoting the expression of IL-1β and cell proliferation. The findings from our study provide a basis for the efficient treatment of OA by investigating the inhibitory effects of miR-206 on autophagy and apoptosis of articular cartilage in OA via activating the IGF-1-mediated PI3K/AKT-mTOR signaling pathway.