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.

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.

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.

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.

The Conditions for Se-Enzymes, NO, cGMP and LDL to be Formed and How They are Connected with Each Other

Transportation of energy and substances is fundamental for the conditions of life. The energy from metabolised food is yielded at the reduction of oxygen by the assistance of Se-enzymes. Activated Se-enzymes contain an electron conducting Se-link with elemental Se bounded to Se-cys （Se-cystein） that prevents electron transferring （autoxidable） agents, as arginine, from oxidations. NO is formed from e.g. arginine during the passive state of a Se-enzyme. With NO, instead of O2, bounded to a hem group, destroying oxidations are avoided. This is the role of NO. A nerve signal is activated by the GTP （guanosine triphosphate）-induced triggered transformation of cGMP （cyclic guanosine monophosphate） into GMP, closing the sodium channels. When GTP is consumed, the opposite reaction takes place. The direct influence of the GMP/cGMP quote on a nerve signal makes GMP/cGMP equal to EDHF （endothelium-derived hyperpolarizing factor）. Part of the energy from food is stored and transported in the form of acetyl groups, building up many important molecules of which LDL （low density lipoprotein） is one, containing cholesteryl esters. These are brought in to the cell, decomposed to acetyl groups generating hydrogen, H, making LDL to an essential substance. High levels are connected to impaired energy yielding reactions, perhaps related to low levels of some substances, especially to one or both forms of Se. The necessity of a Se-link and NO induced protection against oxidations by reducible oxygen can no longer be neglected.

Enhancement of human ACAT1 gene expression to promote the macrophage-derived foam cell formation by dexamethasone

In macrophages, the accumulation of cholesteryl esters synthesized by the activated acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT1) results in the foam cell formation, a hallmark of early atherosclerotic lesions. In this study, with the treatment of a glucocorticoid hormone dexamethasone (Dex), lipid staining results clearly showed the large accumulation of lipid droplets containing cholesteryl esters in THP-1-derived macrophages exposed to lower concentration of the oxidized low-density lipoprotein (ox-LDL). More notably, when treated together with specific anti-ACAT inhibitors, the abundant cholesteryl ester accumulation was markedly diminished in THP-1-derived macrophages, confirming that ACAT is the key enzyme responsible for intracellular cholesteryl ester synthesis. RT-PCR and Western blot results indicated that Dex caused up-regulation of human ACAT1 expression at both the mRNA and protein levels in THP-1 and THP-1-derived macrophages. The luciferase activity assay demonstrated that Dex could enhance the activity of human ACAT1 gene P1 promoter, a major factor leading to the ACAT1 activation, in a cell-specific manner. Further experimental evidences showed that a glucocorticoid response element (GRE) located within human ACAT1 gene P1 promoter to response to the elevation of human ACAT1 gene expression by Dex could be functionally bound with glucocorticoid receptor (GR) proteins. These data supported the hypothesis that the clinical treatment with Dex, which increased the incidence of atherosclerosis, may in part due to enhancing the ACAT1 expression to promote the accumulation of cholesteryl esters during the macrophage-derived foam cell formation, an early stage of atherosclerosis.

Genetic variants involved in gallstone formation and capsaicin metabolism,and the risk of gallbladder cancer in Chilean women

AIM:To determine the effects of genetic variants associated with gallstone formation and capsaicin (a pungent component of chili pepper) metabolism on the risk of gallbladder cancer (GBC).METHODS: A total of 57 patients with GBC, 119 patients with gallstones, and 70 controls were enrolled in this study. DNA was extracted from their blood or paraffi n block sample using standard commercial kits. The statuses of the genetic variants were assayed using Taqman SNP Genotyping Assays or Custom Taqman SNP Genotyping Assays.RESULTS:The non-ancestral T/T genotype of apolipoprotein B rs693 polymorphism was associated with a decreased risk of GBC (OR:0.14,95% CI:0.03-0.63). The T/T genotype of cholesteryl ester transfer protein (CETP) rs708272 polymorphism was associated with an increased risk of GBC (OR:5.04,95% CI:1.43-17.8).CONCLUSION: Genetic variants involved in gallstone formation such as the apolipoprotein B rs693 and CETP rs 708272 polymorphisms may be related to the risk of developing GBC in Chilean women.

Natural history and management of liver dysfunction in lysosomal storage disorders

Lysosomal storage disorders(LSD)are a rare group of genetic disorders.The major LSDs that cause liver dysfunction are disorders of sphingolipid lipid storage[Gaucher disease(GD)and Niemann-Pick disease]and lysosomal acid lipase deficiency[cholesteryl ester storage disease and Wolman disease(WD)].These diseases can cause significant liver problems ranging from asymptomatic hepatomegaly to cirrhosis and portal hypertension.Abnormal storage cells initiate hepatic fibrosis in sphingolipid disorders.Dyslipidemia causes micronodular cirrhosis in lipid storage disorders.These disorders must be keenly differentiated from other chronic liver diseases and non-alcoholic steatohepatitis that affect children and young adults.GD,Niemann-Pick type C,and WD also cause neonatal cholestasis and infantile liver failure.Genotype and liver phenotype correlation is variable in these conditions.Patients with LSD may survive up to 4-5 decades except for those with neonatal onset disease.The diagnosis of all LSD is based on enzymatic activity,tissue histology,and genetic testing.Enzyme replacement is possible in GD and Niemann-Pick types A and B though there are major limitations in the outcome.Those that progress invariably require liver transplantation with variable outcomes.The prognosis of Niemann-Pick type C and WD is universally poor.Enzyme replacement therapy has a promising role in cholesteryl ester storage disease.This review attempts to outline the natural history of these disorders from a hepatologist’s perspective to increase awareness and facilitate better management of these rare disorders.

Prevention of fatal hepatic complication in schistosomiasis by inhibition of CETP

Schistosoma japonicum, once endemic all the East Asia, remains as a serious public health problem in certain regions. Ectopic egg embryonation in the liver causes granulomatosis and eventually fatal cirrhosis, so that prevention of this process is one of the keys to reduce its mortality. The embryonation requires cholesteryl ester from HDL of the host blood for egg yolk formation, and this reaction is impaired from the abnormal large HDL in genetic cholesteryl ester transfer protein （CETP） deficiency. When CETP was expressed in mice that otherwise lack this protein, granulomatosis of the liver was shown increased compared to the wild type upon infec- tion of Schistosoma japonicum. The CETP deficiencies accumulated exclusively in East Asia, from Indochina to Siberia, so that Shistosomiasis can be a screening factor for this accumulation. CD36 related protein （CD36RP） was identified as a protein for this reaction, cloned from the cDNA library of Schistosoma japonicum with 1880-bp encoding 506 amino acids. The antibody against the extracellular loop of CD36RP inhibited cholesteryl ester uptake from HDL and suppressed egg embryonation in culture. Therefore, inhibition of CETP is a potential approach to prevent liver granulomatosis and thereby fatal liver cirrhosis in the infection of Schistosoma japonicum.

The effects of fucoidans from Laminaria japonica on AAPH mediated oxidation of human low-density lipoprotein

Five fucoidan fractions from Laminaria japonica with different sulfate content and molecular weight were prepared by anion-exchange chromatography and mild acid hydrolysis. Their antioxidant effects on azo radicals 2-2＇-Azobis （2-amidinopropane） dihydrochloride （AAPH） induced oxidation of human low-density lipoprotein （LDL） were evaluated by monitoring cholesteryl ester hydroperoxides （CHL-OOH） formation kinetics through reverse-phase high performance liquid chromatography （RP-HPLC） analysis. Fucoidan F - C with a low molecular mass of 2 000 ～8 000 and a sulfate content of 24.3% had much stronger protective antioxidant effect than other four fucoidan fractions on the hydrophilic radical AAPH induced LDL oxidation. However, the highly sulfated fucoidan fraction L - B with a molecular mass of 20 000 was completely ineffective in protecting LDL from the AAPH induced oxidation. The results suggested that both molecular mass and sulfate content of fucoidan played very important roles in their effects on the AAPH induced LDL oxidation.

Novel LIPA mutations in Mexican siblings with lysosomal acid lipase deficiency

Lysosomal acid lipase(LAL) deficiency is an underrecognized lysosomal disease caused by deficient enzymatic activity of LAL.In this report we describe two affected female Mexican siblings with early hepatic complications.At two months of age,the first sibling presented with alternating episodes of diarrhea and constipation,and later with hepatomegaly,elevated transaminases,high levels of total and low-density lipoprotein cholesterol,and low levels of highdensity lipoprotein.Portal hypertension and grade 2 esophageal varices were detected at four years of age.The second sibling presented with hepatomegaly,elevated transaminases and mildly elevated lowdensity lipoprotein and low high-density lipoprotein at six months of age.LAL activity was deficient in both patients.Sequencing of LIPA revealed two previously unreported heterozygous mutations in exon 4:c.253C>A and c.294C>G.These cases highlight the clinical continuum between the so-called Wolman disease and cholesteryl ester storage disease,and underscore that LAL deficiency represents a single disease with a degree of clinical heterogeneity.

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.

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.

Fluorescence study on the coaggregating tendencies of the cholesterols --the culprits of arteriosclerosis

The coaggregating tendencies of the culprits of arteriosclerosis, the cholesteryl esters (CE-n's), have been investigated in the 40:60 V/V (Φ= 0.40) dioxane (DX)-H2O system, by using decyl pyrenyl ketone (Py-11) as the fluorescence probe. The fluorescence intensity of Py-11 decreases when coaggregation occurs between CE-n and Py-11, because of the low polarity of the microenviroment of the coaggregates. The order of the coaggregating tendencies obtained from the fluorescence data is in full agreement with that from the kinetic method, i.e., CE-ol, CE-in > CE-12 > CE-8 > CE-18 > CE-0.