Pathogenic contribution of cholesteryl ester accumulation in the brain to neurodegenerative disorders

Cholesteryl esters(CEs) have been increasingly implicated in neurodegenerative disorders such as Alzheimer's disease(AD).Alois Alzheimer noted three prominent neuropathologic features in his original analysis of the AD brain:senile plaques,neurofibrillary tangles,and lipid granule accumulation.Senile plaques,which are aggregates of amyloid-beta(Aβ),and neurofibrillary tangles,which are aggregates of phosphorylated tau,have been regarded as more consistent characteristics of the AD brain compared with lipid granule accumulation and thus have been studied more intensively(Foley,2010).

Synthesis of Amphiphilic Hepatocyte Targeting Cholesterylated Thiogalactosides

Six amphiphilic cholesterylated thiogalactosides la-f with high affinity for the asialoglycoprotein receptor have been synthesized by coupling 2,3,4,6-tetra -O-acetyl-l-thio-β-D-galactopyranose 8 with prepared cholesterol derivatives 7a-f, then by deacetylating. Preliminary results show liposomes containing those galactosides derivatives exhibited higher affinity and transfection activity in hepatoma cells HepG2 and SMMC-7721.

Effect of Tumor Necrosis Factor-α on Acyl Coenzyme A: Cholesteryl Acyltransferase Activity and ACAT1 Gene Expression in THP-1 Macrophages

In order to explore the effect and mechanisms of tumor necrosis factor-α （TNF-α） on the activity of the acyl coenzyme A： cholesteryl acyltransferase （ACAT）, THP-I monocytes were cul- tured and induced to differentiate into macrophages with phorbol ester. TNF-α （60 ng/mL） was added at different time points into the macrophage-containing medium and the ACAT enzyme activity was measured by quantifying the incorporation of [1-^14C] oleoyl CoA into cholesteryl esters. The expression of ACAT-1 protein and mRNA was respectively detected by Western blotting and RT-PCR in THP-1 macrophages 24 h after treatment with TNF-α （60 ng/mL）. The results indicated that ACAT activity in THP-I macrophages treated with TNF-α was increased in a time-dependent manner. The expression levels of ACAT-1 protein and mRNA were significantly increased in THP-I macrophages after treatment with TNF-α （P〈0.05）. It was suggested that TNF-α could increase the activity of ACAT in THP-1 macrophages by up-regulating the expression of ACAT-1 gene.

High level of serum cholesteryl ester transfer protein inactive hepatitis C virus infection

AIM: To determine the significance of cholesteryl ester transfer protein(CETP) in lipoprotein abnormalities in chronic hepatitis C virus(HCV) infection.METHODS: We evaluated the significance of the serum concentration of CETP in 110 Japanese patients with chronic HCV infection. Fifty-five patients had active HCV infection, and HCV eradication had been achieved in 55. The role of CETP in serum lipoprotein abnormalities, specifically, in triglyceride(TG) concentrations in the four major classes of lipoproteins, was investigated using Pearson correlations in conjunction with multiple regression analysis and compared them between those with active HCV infection and those in whom eradication had been achieved. RESULTS: The serum CETP levels of patients with active HCV infection were significantly higher than those of patients in whom HCV eradication was achieved(mean ± SD, 2.84 ± 0.69 μg/m L vs 2.40 ± 1.00 μg/m L, P = 0.008). In multiple regression analysis, HCV infection status(active or eradicated) was an independent factor significantly associated with the serum CETP level. TG concentrations in low-density lipoprotein(mean ± SD, 36.25 ± 15.28 μg/m L vs 28.14 ± 9.94 μg/m L, P = 0.001) and high-density lipoprotein(HDL)(mean ± SD, 25.9 ± 7.34 μg/m L vs 17.17 ± 4.82 μg/m L, P < 0.001) were significantly higher in patientswith active HCV infection than in those in whom HCV eradication was achieved. The CETP level was strongly correlated with HDL-TG in patients with active HCV infection(R = 0.557, P < 0.001), whereas CETP was not correlated with HDL-TG in patients in whom HCV eradication was achieved(R =-0.079, P = 0.56). CONCLUSION: Our results indicate that CETP plays a role in abnormalities of lipoprotein metabolism in patients with chronic HCV infection.

Synthesis of Novel Lipids Bearing Cholesteryl Group as Gene Vectors

Some cationic and neutral lipids bearing cholesteryl group were synthesized as gene vectors, and the structures of the compounds were characterized by IR, (HNMR)-H-1, MS and elemental analysis.

Tag single nucleotide polymorphism rs1532624 located in cholesteryl ester transfer protein gene is associated with atherosclerosis cerebral ischemia

Objective: To investigate the relationship between polymorphisms of rs1532624 and rs289741 loci in cholesteryl ester transfer protein(CETP) genes and atherosclerotic cerebral infarction(ACI). Methods: The CETP gene rs1532624 and rs289741 in 95 patients with ACI and 177 healthy subjects were genotyped by Mass ARRAY mass spectrometry. Each locus genotype and allele frequency distributions were compared. Results: The difference of allele frequency distribution between the rs1532624(χ~2=1.723, P=0.189) and rs289741(χ~2=2.466, P=0.116) were not statistically significant. The frequency distribution of rs1532624 genotype between the cerebral infarction group and healthy control group was statistically significant(χ~2=7.096, P=0.029), while rs289741 genotype frequency distribution between the two groups was not statistically significant(χ~2=2.906, P=0.234). Conclusion: ACI have a positive correlation with rs1532624 polymorphism, and AA genotype may be susceptible factors of ACI.

Qualitative Distribution of Endogenous Cholesteryl Esters in Plasma of Humans and Three Rodent Species Using Stepwise UPLC-Q-Exactive-MS

Objective:Cholesteryl esters(CEs)are composed of various fatty acyl chains attached to the hydroxyl groups of cholesterol,and abnormalities in their metabolism are related to many diseases.This study aimed to develop an ultrahigh-performance liquid chromatography-quadrupole exactive mass spectrometry(UPLC-Q-Exactive MS)method to identify the CEs in plasma.Methods:First,the MS fragmentation patterns were investigated using seven commercial CE standards.Then,the CEs in plasma were characterized through the accurate mass data of precursor ions and characteristic product ions.A strategy of step-by-step m/z scans in a narrow range was proposed to identify more trace CEs by the full-scan data-dependent MS/MS(ddMS2)mode.Results:A total of 50 CE species consisting of 55 regioisomers were identified in human plasma.Among them,two species were reported for the first time.Conclusion:This study is the most comprehensive identification of CE species in human plasma to date.These results will contribute to the in-depth profiling of CEs in human plasma and provide guidance for animal model selection when studying lipid-related diseases.

SPECTROSCOPIC DETERMINATION OF THE AVERAGE NUMBER OF COAGGREGATES (Nco) OF CHOLESTERYL ESTERS AND THE FLUORESCENCE PROBE

Average aggregate number of coaggregates(N_co)of CE-n or BL-n and the fluoresc- ence probe(Np-16)have been determined by using time-resolved fluorescence spectroscopy. Chain-length,hydroxy-group and chain-foldability effects on the N_co have been discussed.

Synthesis and Characterization of Mesomorphic Behaviour of New Mesogenic Compounds Incorporating Cholesteryl Ester Moiety Connected to 1,3,4-Oxadiazole

The synthesis and characterization of new series of liquid crystals containing cholesteryl moiety connected via an ester linkage to 1,3,4-oxadiazole are reported. The molecular structures of the intermediates and target compounds were confirmed by elemental analyses and FT-IR, ^1H NMR and mass spectrometry. The mesomorphic behaviors were investigated by polarizing optical microscopy （POM） attached with hot stage and differential scanning calorimetry （DSC）. Enantiotropic smectic 1, smectic A, blue phase and cholesteric mesophases are exhibited by the newly synthesized compounds.

Pharmacophore-based design,synthesis,and biological evaluation of novel 3-((3,4-dichlorophenyl)(4-substituted benzyl)amino)propanamides as cholesteryl ester transfer protein(CETP)inhibitors

Cholesteryl ester transfer protein （CETP） is a plasma glycoprotein that plays an important role in decreasing high-density lipoprotein cholesterol （HDL-C） levels and increasing low-density lipoprotein cholesterol （LDL-C） levels. Inhibition of CETP may be a new therapy for treating atherosclerosis. Herein, we report the development of a ligand-based pharmacophore model and pharmacophore-based virtual screening of the ZINC/big-n-greasy database, leading to the identification of compound H-10 as a potential CETP inhibitor in vitro. Based on H-10, a series of 3-（（3,4-dichlorophenyl）（4-substituted benzyl）amino） propanamides were designed, synthesized, and evaluated against CETP. Compound 41 was found to have the best activity, resulting in 85.0% inhibition of CETP at l0 μmol/L.

Association between TaqIB polymorphism of cholesteryl ester transfer protein and coronary artery disease in the Chinese population

Objective: To assess whether the TaqIB polymorphism of cholesteryl ester transfer protein (CETP) is associated with coronary artery disease (CAD) in Chinese population, we performed a meta-analysis in this paper. Methods: We searched PubMed, Embase, the Science Citation Index (SCI), the China Biological Medicine database (CBM), the China National Knowledge Infrastructure (CNKI), and the Wanfang database for relevant articles. Data were extracted, and pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Results: The lit- erature search yielded 448 studies, in which 10 case-control studies including 1 694 cases and 1 456 controls matched the selection criteria. The combined B1 and B2 allele frequencies were 0.587 and 0.413, respectively. The pooled OR was 1.10 (95% CI, 0.89-1.34) for comparing the B1B1 or B1B2 carriers with B2B2 carriers, and was 1.27 (95% CI, 1.09-1.49) in the B1B1 carriers versus B2B2 or B1B2 carriers. Conclusions: In the present study, the TaqIB poly- morphism of CETP was found to be associated with CAD in the Chinese population.

A New Initiator Cholesteryl Chloroformate for Cupper-Based Atom Transfer Radical Polymerization of Methyl Methacrylate

The polymerization of metyl methacrylate (MMA) was studied in detail by use of CuCl/L as a catalyst and cho-lesteryl chloroformate (CC) as an initiator. It was found that the atom transfer radical polymerization of MMA could proceed when L equals to a multidentate aliphatic amine ligand, N,N,N',N'',N″-penta(methyl acry-late)diethylenetriamine (MA5-DETA), and no polymerization was occurred while L=2,2'-bipyridine and 1,10- phenanthroline. The linear proportionality of the molecular weights to the conversions and straight lines observed in ln[M]0/[M] versus time plots indicated that the present polymerization system had the typical controlled polymeri-zation characteristics.

Low and Wide Phase Transition Temperature Dimesogenic Compounds Consisting of a Cholesteryl and 4-（trans-4-n-Alkylcyclohexyl）phenoxy Mesogens

Unsymmetrical dimesogenic compounds with cholesteryl and 4-（trans-4-n-alkylcyclohexyl）phenoxy parts were synthesized by condensation of cholester-3-yl 6-bromohexanoate with appropriate 4-（trans-4-n-alkylcyclohexyl）- phenols. Structures and thermal phase behaviour of these dimesogenic compounds have been confirmed by IR, IH NMR, elemental analysis, DSC, polarity microscopy and XRD measurements. Their thermal phase behaviour was significantly different with that of other cholesterol-based dimesogens while they exhibited low and wide phase transition temperature.

Self-assembly behaviors of the cholesteryl trimeric-phenylene vinylene derivative in the H_2 O/THF system

Cholesteryl trimeric phenylene vinylene （ChoI-TPV） has been synthesized and characterized. The self- assembly behaviors of ChoI-TPV in THF/H20 system at different water content （water content： 40% and 80%） and different solute concentration （solute concentration： 1.0 ×10^-5 mol/L and saturated concentration） were studied using UV-vis spectrophotometry, photoluminescence spectrophotometry, and circular dichroism spectroscopy. Based on an analysis of the UV-vis and photoluminescence spectra, Chol-TPV shows the typical H-type aggregation at saturated concentration in 80% aqueous THF. However, ChoI-TPV shows the non-typical H-type aggregation under other conditions. The circular dichroism signal suggests that the Chol-TPV exists in the right handed helical architectures with high water content at a concentration of 1.0 × 10^-5 mol/L, and a helix inversion was found at saturated concentration.

Taq1B polymorphism and plasma activity of cholesteryl ester transfer protein and restenosis after coronary stent placement

Cholesteryl ester transfer protein （CETP）, an important regulatory factor in reverse cholesterol transport, has been investigated in relation to plasma HDL cholesterol, which is associated with restenosis after percutaneous transluminal coronary angioplasty （PTCA） and stent implantation. We examined the effect of plasma CETP activity and the Taq1B polymorphism on restenosis in Chinese HaM population. Methods and Results Our study included 228 patients with symptomatic coronary artery disease （CAD）. The genotype of the subjects for Taq1B polymorphism of CETP was analyzed by using polymerase chain reaction-restriction fragment length poly- morphism （PCR-RFLP）. In-stent restenosis （ISR） was observed in 93 patients （40.8 %）. Baseline clinical, angiographic,and procedural characteristics data were not significantly different in patients with and without restenosis,except previous history of myocardial infarction （MI）, left ventricular ejection fraction （LVEF）, statin medication, and stent type. Taq1B polymorphism and plasma activity of CETP were not associated with the incidence of ISR （P = 0.68, P = 0.30, respectively）. Linear regression analysis revealed that the risk of ISR was statistically significant correlation with stent type, LVEF, statin medication, and lesion length （P 〈 0.05）. Conclusions Useful markers for risk of ISR were stent type, LVEF, statin medication and lesion length but not the Taq1B polymorphism and plasma activity of CETP.

母乳中胆固醇及胆固醇酯分布规律研究

该研究利用超高效液相色谱-高分辨质谱技术对母乳中胆固醇和胆固醇酯进行系统性定性定量分析,分析不同泌乳阶段(初乳1~7 d、过渡乳8~15 d、成熟乳16 d以后)胆固醇及胆固醇酯组成及含量差异。结果表明,除胆固醇外,初乳、过渡乳和成熟乳中分别存在13、11、7种微量胆固醇酯,整个泌乳期中二十四酸胆固醇酯(C24∶0)和棕榈酸胆固醇酯(C16∶0)含量最高。母乳中胆固醇及胆固醇酯含量存在较大的个体差异,但总体上呈现出初乳中胆固醇及胆固醇酯的含量均为最高。其中不同的胆固醇酯之间表现出一定相关性,尤其是二十二碳烯酸胆固醇酯(C22∶1)与硬脂酸胆固醇酯(C18∶0)具有极强的相关性(皮尔逊相关系数为0.88)。研究结果可为婴配食品的生产研发提供借鉴和参考。

基于电场调控的胆固醇基液晶薄膜对成纤维细胞生长分化的影响

通过外加电场对胆固醇-g-聚乳酸低聚物(Cholesteryl-oligo(L-lactic acid),CLA)薄膜的液晶有序性进行调节,并评价其对成纤维细胞黏附、增殖和分化的影响。采用差示扫描量热仪检测CLA聚合物液晶性;以外加直流电场调控薄膜液晶有序性,X射线衍射仪和偏光显微镜检测电场调控下CLA薄膜液晶有序性的改变;Cell Counting Kit-8试剂盒检测成纤维细胞在CLA薄膜上的黏附与增殖行为,免疫荧光染色法和蛋白免疫印迹法检测成纤维细胞表型转化特征蛋白α-平滑肌肌动蛋白(α-Smooth muscle actin, α-SMA)表达水平。结果表明,CLA聚合物具有液晶性,外加电场可通过诱导CLA液晶分子的有序排列调控CLA薄膜液晶性,CLA薄膜液晶性增强有利于成纤维细胞的增殖与α-SMA蛋白表达。说明电场调控可在不改变CLA聚合物薄膜基质材料组成的前提下,通过增加薄膜的液晶有序性,促进成纤维细胞向肌成纤维细胞表型转化。

胆固醇酯对非酒精性脂肪肝药物治疗的影响

胆固醇酯(cholesteryl ester,CE)是胆固醇过量时的储存产物。研究表明CE在多种代谢类疾病的诊疗中都扮演着重要角色,然而膳食摄入CE对非酒精性脂肪肝(non-alcoholic fatty liver disease,NAFLD)药物治疗的影响仍不清晰。作者以非诺贝特(fenofibrate,Feno)治疗的NAFLD小鼠为模型,通过膳食补充CE研究其对非诺贝特治疗效果的影响。结果表明,非诺贝特可有效缓解NAFLD的症状,而膳食补充CE后削弱了非诺贝特对NAFLD的治疗效果。此外,转录组学以及RT-QPCR分析表明,膳食补充CE可逆转非诺贝特调控的脂肪酸代谢以及胆固醇酯化相关基因Soat1和Soat2 mRNA的表达。以上结果表明,膳食添加CE可显著影响NAFLD的药物治疗效果,推测当饮食中CE质量分数较高时,非诺贝特的治疗效果将被降低。该研究为非酒精性脂肪肝患者接受药物治疗期间的合理膳食提供了理论依据。

胆固醇修饰的氨基酸类有机凝胶因子去除水中亚甲基蓝的研究

设计合成了胆固醇修饰的氨基酸类有机凝胶因子CH-1和CH-2,并对其去除水中的亚甲基蓝进行了系统地研究.结果表明,CH-2粉末能够去除水中的亚甲基蓝,CH-1与低毒的苯甲醇形成的凝胶也可以快速去除水中的亚甲基蓝.

基于UPLC-MS/MS的人血浆胆固醇酯分子检测方法及其在冠心病患者中的应用

目的使用高通量超高效液相色谱-串联质谱(ultra-performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)建立人血浆中各胆固醇酯分子的测量方法,并对患者血浆样本实现定量分析。方法使用UPLC-MS/MS,以基质效应、检测限、回收率、精确度、准确度等方法学评价指标对13种胆固醇酯标准品进行方法学验证,同时收集来自首都医科大学附属北京安贞医院的稳定型冠心病患者、急性心肌梗死患者与体检中心对照人群血样各50例,检测血浆中13种胆固醇酯的分子水平,比较各组结果差异。结果通过对胆固醇酯标准品的方法学验证,本检测方案达到定量检测方法学验证要求。对人血样检测结果显示,胆固醇酯CE 22∶0、CE 22∶5、CE 20∶5、CE 18∶0、CE 18∶3等分子与冠心病的发生发展相关。结论基于UPLC-MS/MS高通量、高灵敏度和高特异性的检测特性,本文建立的胆固醇酯分子检测方法能够对血浆中多种胆固醇酯分子实现良好的分离和检测,为精准测量不同胆固醇酯分子提供了方法学参考。