Determination of the inhibition profiles of pyrazolyl–thiazole derivatives against aldose reductase and α-glycosidase and molecular docking studies

Aldose reductase (AR) is the first and rate-limiting enzyme of the polyol pathway, which converts glucose to sorbitol in an NADPH-dependent reaction. α-Glycosidase breaks down starch and disaccharides to glucose. Hence, inhibition of these enzymes can be regarded a considerable approach in the treatment of diabetic complications. AR was purified from sheep liver using simple chromatographic methods. The inhibitory effects of pyrazolyl–thiazoles ((3aR,4S,7R,7aS)-2-(4-{1-[4-(4-bromophenyl)thiazol-2-yl]-5-(aryl)-4,5-dihydro-1H-pyrazol-3-yl}phenyl)-3a,4,7,7a-tetrahydro-1H-4,7-methanoisoindole-1,3(2H)-dione derivatives; 3a – i ) on AR and α-glycosidase enzymes were investigated. All compounds showed a good inhibitory action against AR and α-glycosidase. Among these compounds, compound 3d exhibited the best inhibition profiles against AR, with a K_i value of 7.09 ± 0.19 µM, whereas compound 3e showed the lowest inhibition effects, with a K_i value of 21.89 ± 1.87 µM. Also, all compounds showed efficient inhibition profiles against α-glycosidase, with K_i values in the range of 0.43 ± 0.06 to 2.30 ± 0.48 µM, whereas the K_i value of acarbose was 12.60 ± 0.78 µM. Lastly, molecular modeling approaches were implemented to predict the binding affinities of compounds against AR and α-glycosidase. In addition, the ADME analysis of the molecules was performed.     

基于网络药理学和分子对接法探讨槲皮素治疗2型糖尿病的作用机制

目的 基于网络药理学和分子对接技术探讨槲皮素治疗2型糖尿病（T2DM）的作用机制。方法 通过TCMSP和PharmMapper数据库查询槲皮素的作用靶点,Genecards和CTD数据库收集T2DM的相关靶点,求出槲皮素-T2DM交集靶点并利用STRING和DAVID数据库对交集靶点进行通路分析,使用Cytoscape 3.6.1软件进行\"靶点-通路\"网络的构建,利用Auto Dock Vina进行分子对接预测槲皮素对T2DM作用靶点的结合能。结果 筛选出槲皮素的潜在靶点312个,与T2DM相关的靶点121个,核心靶点6个：NOS3、CYP1B1、NOS2、TGFB1、TTR和CDKN1A。KEGG信号通路30条,涉及toll样受体信号通路、MAPK信号通路、胰岛素信号通路等。分子对接结果显示,槲皮素与6个核心基因的分子对接亲和力均远小于-20 kJ/mol,结合活性较好。结论 槲皮素治疗T2DM具有多靶点、多通路的作用特点,可能是通过作用于NOS3、CYP1B1、NOS2等核心基因调控toll样受体信号通路、MAPK信号通路、胰岛素信号通路等发挥作用。     

结合生物信息学和分子对接技术探讨基于肝糖异生抑制策略治疗2型糖尿病的靶标蛋白标志物

目的 基于肝糖异生抑制策略筛选2型糖尿病(type 2 diabetes mellitus,T2DM)的标志性靶标蛋白。方法 从NCBI数据库下载人类肝组织基因芯片数据集,使用GEO2R在线分析工具筛选T2DM易感性基因;利用GeneCards和OMIM数据库检索糖异生相关靶点;整合数据获取T2DM-肝糖异生交互靶点,并构建蛋白质间相互作用网络筛选标志性靶标蛋白;使用Metascape数据库对靶点进行基因本体论和通路富集分析;借助分子对接预测T2DM治疗药物与标志性靶标蛋白之间的相互作用能力;最后联合二甲双胍对标志性靶标蛋白在自发性T2DM KKAy小鼠肝组织中的影响进行验证。结果 共识别出1 143个T2DM易感性基因和958个糖异生相关靶点,获得56个T2DM-肝糖异生交互靶点,并经网络分析筛选出2个标志性靶标蛋白PTPRC和VCAM1;交互靶点主要富集在葡萄糖分解代谢、典型糖酵解、葡萄糖-6-磷酸糖酵解等生物过程,通过糖酵解/糖异生、糖尿病并发症中的AGE-RAGE信号通路、内分泌抵抗等通路调节发挥作用;26个降糖药物均与标志性靶点同时具有较好的空间匹配、能量匹配以及不同程度的结合能力;T2DM模型组小鼠血糖较正常组显著增高,且在治疗后显著降低;T2DM模型组小鼠肝组织中PTPRC、VCAM1的蛋白表达水平均较正常对照组显著增高,并且均在二甲双胍治疗后显著降低。结论 本研究系统筛选并验证了肝组织中可能影响T2DM肝糖异生的2个标志性靶标蛋白,揭示了T2DM中肝糖异生调控通路,为深入研究肝糖异生防治机制,寻找新的降糖药物作用靶点提供依据。     

基于系统药理学探讨草乌改善Ⅱ型糖尿病的分子机制

目的 基于系统药理学、生物信息学、分子对接及体内外实验探讨草乌影响 2 型糖尿病(diabetes mellitus type 2,T2DM)的潜力及对 T2DM 相关症状的潜在机制。方法 利用数据库检索草乌相关化学成分、预测潜在作用靶点以及干预相关疾病;GEO 数据库检索 T2DM 相对健康人的差异基因,与草乌作用靶点映射后置于 DAVIDavid 数据库进行生物功能富集,利用单因素方差分析、二元 Logistic 回归分析及 ROC 曲线分析目标基因对于 T2DM 的敏感性。借助分子对接技术分析草乌化学成分与靶蛋白的结合位置及相互作用力。通过体内外 T2DM 模型验证草乌及其化学成分对目标蛋白表达的影响。 结果 通过数据库检索与分析得到草乌干预靶点相关疾病 44 种(P value<0.05,FDR<0.05),选取度值最高的T2DM(Degree=22)进行分析。T2DM 相对健康人差异基因与草乌潜在作用靶点取交集得到 43 个目标基因,进行单因素方差分析得到有显著性差异的基因共 9 个,二元 Logistic 回归分析得到 5 个有意义基因,ROC 曲线下面积 AUC>0.5 的基因共 3 个。分子对接得到草乌化学成分(+)-Isoboldine 与蛋白 APEX1、CASP1、CBFB,Napelline 与蛋白 CBX1、EHMT2 结合通过氢键相互作用、疏水相互作用、可电离性和静电相互作用等不同作用力结合,从而增加配体靶向作用蛋白的能力。体内模型经草乌水提物治疗 2 周后,草乌可能通过改善周围神经病变进而缓解 T2DM 症状。并且草乌可以影响大鼠肝组织中 APEX1、CASP1、CBFB、CBX1、EHMT2 的蛋白表达,草乌中(+)-Isoboldine 和 Napelline 化学成分对体外模型的目标蛋白的影响与体内实验一致。结论 初步揭示草乌可作为改善 T2DM 周围神经病变的潜在治疗药物,为中蒙药研发以及挖掘治疗 T2DM 新靶标药物奠定理论基础。     

基于网络药理学和分子对接技术探讨三黄糖肾康治疗2型糖尿病的分子作用机制

目的 基于网络药理学和分子对接技术探讨三黄糖肾康治疗2型糖尿病（T2DM）的分子作用机制。方法 利用TCMSP、SymMap、TCMID和TCM Databases@Taiwan数据库采集三黄糖肾康的有效成分,通过检索文献来补充水蛭的有效成分,在上述数据库及Swiss Target Prediction数据平台获取对应的靶点。借助GeneCards、OMIM、TTD数据库获取T2DM相关靶点。将药物–疾病共同靶点利用String 11.5和Cytoscape 3.9.0构建蛋白互作网络（PPI）图,筛选出核心靶点,通过DAVID数据库进行基因本体（GO）和京都基因与基因组百科全书（KEGG）分析。利用Autodock tools 1.5.7将PPI网络图前3位靶点和对应的有效成分进行分子对接。结果 三黄糖肾康治疗T2DM的有效成分有63个,159个潜在靶点,通过筛选得到STAT3、INS、AKT1等54个核心靶点,槲皮素、小檗碱、木犀草素、大黄酸等58个关键成分。核心靶点主要涉及HIF-1信号通路、PI3K-Akt信号通路、TNF信号通路等115条通路。STAT3与大黄酸、AKT1与槲皮素和木犀草素、INS与小檗碱分子对接良好。结论 三黄糖肾康可通过多个靶点、多条通路对2型糖尿病发挥调控作用。     

雌激素受体α36亚型配体结合区的结构模建、优化及验证

目的雌激素受体（estrogenreceptor,ER）参与多种重要的体内生理过程,是一个重要的受体家族。新近发现的雌激素受体036亚型（ER—a36）通过新的作用机制调节体内功能,对其进行开拓性的研究具有重要意义。方法利用已知的ER—α36序列以及两个典型的ER—α66配体结合区的晶体结构,通过同源模建的方法构建了ER—α36配体结合区的结构模型,并采用分子动力学模拟与分子对接等方法对其合理性进行了初步验证。结果与结论ER-α36配体结合区与传统的ER—α66相比具有显著差异,蛋白整体结构缺失四段“螺旋,口袋开放性增加且柔性提高。这些特征导致配体结合特征发生变化。雌二醇、4-羟基-他莫昔芬、genistein和G-1等已知调控分子与ER—α36的对接分析,进一步验证和解释了已报道的生物实验数据。本研究所建立的ER-a36的同源模建模型具有较好的可靠性与准确性,为进一步发现和研究新的选择性ER-α36调控分子和药物奠定了基础。     

Design,Synthesis and Evaluation of Rhodanine Derivatives as Aldose Reductase Inhibitors

Aldose reductase (ALR) enzyme plays a significant role in conversion of excess amount of glucose into sorbitol in diabetic condition, inhibitors of which decrease the secondary complication of diabetes mellitus. To understand the structural interaction of inhibitors with ALR enzyme and develop more effective ALR inhibitors, a series of substituted 5-phenylbenzoate containing N-substituted rhodanine derivatives were synthesized and evaluated for their in vitro ALR inhibitory activity. Docking studies of these compounds were carried out, which revealed that the 5-phenylbenzoate moiety deeply influenced the key π-π stacking while 4-oxo-2-thioxothiazolidines contributed in hydrogen bond interactions. The phenyl ring of benzylidene system occupied in specific pocket constituted from Phe115, Phe122, Leu300 and Cys303 while the rhodanine ring forms a tight net of hydrogen bond with Val47 at anionic binding site of the enzyme. The structural insights obtained from the docking study gave better understanding of rhodanine and macromolecular interaction and will help us in further designing and improving of ALR inhibitory activity of rhodanine analogs.     

Synthesis,Evaluation and Molecular Docking of Thiazolopyrimidine Derivatives as Dipeptidyl Peptidase IV Inhibitors

A series of thiazolopyrimidine derivatives was designed, synthesized and screened for in‐vitro inhibition of Dipeptidyl Peptidase IV (DPP IV). The SAR study indicated the influence of substituted chemical modifications on thiazolopyrimidine scaffold. Compound 9 (IC₅₀ = 0.489 μm ) and 10 (IC₅₀ = 0.329 μm ) having heterocyclic‐substituted piperazine with acetamide linker resulted as most potent DPP IV inhibitors among all the compounds screened. Single dose (10 mg/kg) of both the compounds 9 and 10 significantly reduced glucose excursion during oral glucose tolerance test in streptozotocin induced diabetic rat model. Molecular docking studies illustrated the probable binding mode and interactions of thiazolopyrimidine nucleus and its derivatives at binding site of receptor. The binding site for DPP IV is composed of active site region (catalytic triad of Ser630, Asp708 and His740) including S1 and S2 sub‐pocket. The aryl moiety of compounds 9 , 10 and 11 were observed to occupy S2 binding pocket and interacted with aromatic ring of Tyr662 and Tyr666 acquired through π‐π interaction. Thus, it is indicated that occupancy of the highly hydrophobic S2 pocket is more important for DPP IV inhibitory activity. The present study on substituted thiazolopyrimidine derivatives shows good to moderate inhibitory potential of DPP IV enzyme.     

传统中药中抗动脉粥样硬化PPARα激动剂的虚拟筛选

目的基于传统中药寻找抗动脉粥样硬化的先导药物分子。方法过氧化物酶体增殖物激活受体α(PPARα)是抗动脉粥样硬化的研究热点之一,以该受体为靶标,采用计算机辅助药物分子设计方法中的药效团筛选、分子对接和相互作用模式分析对传统中药数据库进行虚拟筛选。结果从含有37 170个化合物的传统中药数据库中优选出20个活性较好的化合物,通过进一步的氢键作用分析确认3个先导化合物。结论该研究为新型抗动脉粥样硬化PPARα激动剂的发现提供了新的方法和理论依据。     

5-对甲苯磺酰氨基酞酰亚胺衍生物的设计合成及α-糖苷酶抑制活性

目的寻找具有新型结构的OL-糖苷酶抑制剂类降血糖药物。方法N-取代-5-对甲苯磺酰氨基酞酰亚胺类目标化合物（I1～I8）以邻苯二甲酰亚胺为起始物,经硝化后,通过烃化反应在亚胺氮上引入含芳基的不同取代结构,再经还原及磺酰化反应合成;N-取代结构的苯环上含有酚羟基的目标化合物（Ⅱ1～Ⅱ3）采用乙酰化保护后再进行还原及磺酰化、去保护基等步骤制得;目标化合物Ⅱ。和Ⅱ。的合成是以5一硝基酞酰亚胺为原料,先与甲醛反应,在亚胺氮上引入羟甲基,再与酚性结构进行偶联反应引入相应取代基,最后经还原及磺酰化制得。采用4-硝基苯-“-D-吡喃葡萄糖苷反应体系对目标化合物的a一糖苷酶抑制活性进行评价;采用计算机辅助药物设计软件进行分子Docking分析。结果合成了13个未见报道的新化合物,其结构经MS及1H—NMR谱确证。所有目标化合物对酵母a-糖苷酶均表现出明显的抑制活性,其IC50值小于阳性药物阿卡波糖（Acar）;Docking分析显示,5-对甲苯磺酰氨基酞酰亚胺与酶活性催化位点的氨基酸残基能形成多个氢键,N-取代结构以疏水作用或氢键与酶分子产生相互作用而影响酶活性。结论5-对甲苯磺酰氨基酞酰亚胺结构是产生α-糖苷酶抑制活性的有利结构,亚胺氮原子上取代结构对抑酶活性有重要影响,此结果得到分子对接分析的支持。     

Xanthones as potential α-glucosidase non-competition inhibitors: Synthesis,inhibitory activities,and in silico studies

α-glucosidase inhibitors (AGIs) were commonly used in clinical for the treatment of type 2 diabetes. Xanthones were naturally occurring antioxidants, and they may also be potential AGIs. In this study, eleven 1,6- and 1,3-substituted xanthone compounds were designed and synthesized, of which four were new compounds. Their α-glucosidase inhibitory activities in vitro and in silico were evaluated. Five xanthone compounds with higher activity than acarbose were screened out, and the xanthones substituted at the 1,6-positions were more likely to be potential α-glucosidase non-competitive inhibitors. The binding mode of xanthones with α-glucosidase was further studied by molecular docking method, and the results showed that the inhibitory effect of non-competitive inhibitors on site 1 of α-glucosidase may be related to the hydrogen bonds formed by the compounds with amino acid residues ASN165, HIS209, TRY207, ASP243, and SER104. This study provided a theoretical basis of the rapid discovery and structural modification of non-competitive xanthone inhibitors of α-glucosidase.     

Synthesis,characterization, molecular docking,and biological activities of coumarin–1,2,3-triazole-acetamide hybrid derivatives

Coumarins and their derivatives are receiving increasing attention due to numerous biochemical and pharmacological applications. In this study, a series of novel coumarin–1,2,3-triazole-acetamide hybrids was tested against some metabolic enzymes including α-glycosidase (α-Gly), α-amylase (α-Amy), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), human carbonic anhydrase I (hCA I), and hCA II. The new coumarin–1,2,3-triazole-acetamide hybrids showed K_i values in the range of 483.50–1,243.04 nM against hCA I, 508.55–1,284.36 nM against hCA II, 24.85–132.85 nM against AChE, 27.17–1,104.36 nM against BChE, 590.42–1,104.36 nM against α-Gly, and 55.38–128.63 nM against α-Amy. The novel coumarin–1,2,3-triazole-acetamide hybrids had effective inhibition profiles against all tested metabolic enzymes. Also, due to the enzyme inhibitory effects of the new hybrids, they are potential drug candidates to treat diseases such as epilepsy, glaucoma, type-2 diabetes mellitus (T2DM), Alzheimer's disease (AD), and leukemia. Additionally, these inhibition effects were compared with standard enzyme inhibitors like acetazolamide (for hCA I and II), tacrine (for AChE and BChE), and acarbose (for α-Gly and α-Amy). Also, those coumarin–1,2,3-triazole-acetamide hybrids with the best inhibition score were docked into the active site of the indicated metabolic enzymes.     

Synthesis,Evaluation and Molecular Docking of Prolyl‐Fluoropyrrolidine Derivatives as Dipeptidyl Peptidase IV Inhibitors

A series of prolyl‐fluoropyrrolidine derivatives were designed, synthesized and screened for in vitro inhibition of dipeptidyl peptidase IV. The SAR study revealed the influence of substituted chemical modifications on dipeptidyl peptidase IV inhibitory activity. Among all the compounds screened, compound 9 (IC₅₀ = 0.83 μm ) and 10 (IC₅₀ = 0.43 μm ) possessing aryl substituted piperazine with acetamide linker resulted as most potent dipeptidyl peptidase IV inhibitors. Both the compounds 9 and 10 resulted significant reduction in glucose excursion during oral glucose tolerance test in streptozotocin‐induced diabetic rat model at single dose of 10 mg/kg. Molecular docking studies were performed to illustrate the probable binding mode and interactions of prolyl‐fluoropyrrolidine nucleus and its derivatives at binding site of receptor. The fluoropyrrolidine moiety of prolyl‐fluoropyrrolidine derivatives occupied S1 pocket as observed in the crystal structure (PDB id: 2FJP). The compounds 9 and 10 were observed to occupy S2 binding pocket and were observed to have interaction with Arg125, Tyr547 and Ser630 acquired through hydrogen bond. The aryl moiety at piperazine ring was found to extend into the cavity and interacted with Arg358. The observed interactions signalled that occupancy of the highly hydrophobic S2 pocket is very crucial for dipeptidyl peptidase IV inhibitory activity.     

Anti-endotoxin effects of terpenoids fraction from Hygrophila auriculata in lipopolysaccharide-induced septic shock in rats

Context: Hygrophila auriculata (K. Schum) Heine (Acanthaceae) has been traditionally used for the treatment of various ailments such as inflammation, rheumatism, jaundice and malaria.

Objective: The present study aims to separate terpenoid fraction (TF) from alcohol (70%) extract of the whole plant of Hygrophila auriculata and assess its anti-inflammatory activity.

Materials and methods: HPTLC analysis of TF was performed for the estimation of lupeol. Edema was induced in Wistar albino rats by subplanter injection of 0.1?ml of 1% (w/v) carrageenan into the right hind paw after 1?h of TF administration (100 and 200?mg/kg oral). Septic shock was induced by intraperitoneal administration of LPS (100?μg/kg) in rats and interleukins (IL-1β and IL-6), tumor necrosis factor (TNF-α), superoxide dismutase (SOD), lipid peroxidation (LPO), and nitric oxide (NO) were measured in serum. AutoDock 4.2 was used for molecular docking.

Results: Administration of TF significantly (p?<?0.005) restored the serum levels of cytokines, LPO (7.77?±?0.034 versus 4.59?±?0.059?nmole of TBARS), NO (9.72?±?0.18 versus 4.15?±?0.23?µmol nitrite/mg of wet tissue), and SOD (4.89?±?0.036 versus 7.83?±?0.033?Unit/mg protein) compared with the LPS-challenged rats. Analysis of in silico results revealed that TNF-α is the most appropriate target in eliciting anti-inflammatory activity.

Conclusion: The present findings suggest that TF of Hygrophila auriculata possesses great promise as an anti-inflammatory agent which may be due to its antioxidant effect. Molecular docking results could be exploited for lead optimization and development of suitable treatment of inflammatory disorders.     

基于计算机分子模拟技术从天然产物中筛选PPARγ激动剂

目的:采用分子对接技术从天然产物中筛选PPARγ激动剂。方法:研究时间为2021年1月至9月。基于过氧化物酶体增殖物激活受体γ（PPARγ）的PDB晶型结构（PDB Code：6md4）,构建虚拟靶标模型,以天然产物数据库中的1 680个化合物为配体筛选对象,以6md4原配体分子为对照。首先采用SYBYL软件对天然小分...     

α-芋螺毒素特异性结合受体-神经型烟碱乙酰胆碱受体的同源模建及功能预测

目的探讨神经型烟碱乙酰胆碱受体能被其竞争性拮抗剂α-芋螺毒素选择性阻断的机理。方法采用同源模建的方法构建神经型烟碱乙酰胆碱受体α-7亚型的三维空间结构,并利用分子对接的方法与已知空间构像的α-芋螺毒素对接。结果已构建的神经型烟碱乙酰胆碱受体α-7亚型结构合理,并与已知空间构像的α-芋螺毒素对接成功。结论传统的烟碱型乙酰胆碱受体拮抗剂缺乏专一性,而靶向神经元神经型烟碱乙酰胆碱受体的α-芋螺毒素种类多,特异性强,与不同亚单位组成的受体亲和力不同,应用潜力很大。