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[PMID]:28365392
[Au] Autor:Mouritsen OG; Bagatolli LA; Duelund L; Garvik O; Ipsen JH; Simonsen AC
[Ad] Endereço:MEMPHYS - Center for Biomembrane Physics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark. Electronic address: ogm@memphys.sdu.dk.
[Ti] Título:Effects of seaweed sterols fucosterol and desmosterol on lipid membranes.
[So] Source:Chem Phys Lipids;205:1-10, 2017 Jun.
[Is] ISSN:1873-2941
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:Higher sterols are universally present in large amounts (20-30%) in the plasma membranes of all eukaryotes whereas they are universally absent in prokaryotes. It is remarkable that each kingdom of the eukaryotes has chosen, during the course of evolution, its preferred sterol: cholesterol in animals, ergosterol in fungi and yeast, phytosterols in higher plants, and e.g., fucosterol and desmosterol in algae. The question arises as to which specific properties do sterols impart to membranes and to which extent do these properties differ among the different sterols. Using a range of biophysical techniques, including calorimetry, fluorescence microscopy, vesicle-fluctuation analysis, and atomic force microscopy, we have found that fucosterol and desmosterol, found in red and brown macroalgae (seaweeds), similar to cholesterol support liquid-ordered membrane phases and induce coexistence between liquid-ordered and liquid-disordered domains in lipid bilayers. Fucosterol and desmosterol induce acyl-chain order in liquid membranes, but less effectively than cholesterol and ergosterol in the order: cholesterol>ergosterol>desmosterol>fucosterol, possibly reflecting the different molecular structure of the sterols at the hydrocarbon tail.
[Mh] Termos MeSH primário: Desmosterol/química
Bicamadas Lipídicas/química
Alga Marinha/química
Estigmasterol/análogos & derivados
[Mh] Termos MeSH secundário: Varredura Diferencial de Calorimetria
Membrana Celular
Fenômenos Mecânicos
Microscopia de Força Atômica
Microscopia de Fluorescência
Estrutura Molecular
Estigmasterol/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lipid Bilayers); 313-04-2 (Desmosterol); 504ZAM710C (fucosterol); 99WUK5D0Y8 (Stigmasterol)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170620
[Lr] Data última revisão:
170620
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170403
[St] Status:MEDLINE


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[PMID]:27639960
[Au] Autor:Kazkayasi I; Ismail MA; Parrado-Fernandez C; Björkhem I; Pekiner C; Uma S; Cedazo-Minguez A; Burul-Bozkurt N
[Ad] Endereço:Hacettepe University, Faculty of Pharmacy, Department of Pharmacology, 06100, Sihhiye, Ankara, Turkey. Electronic address: inci.kazkayasi@hacettepe.edu.tr.
[Ti] Título:Lack of insulin results in reduced seladin-1 expression in primary cultured neurons and in cerebral cortex of STZ-induced diabetic rats.
[So] Source:Neurosci Lett;633:174-181, 2016 10 28.
[Is] ISSN:1872-7972
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:Several studies demonstrated that Diabetes mellitus (DM) enhances the risk for Alzheimer's disease (AD). Although hyperglycemia and perturbed function of insulin signaling have been proposed to contribute to AD pathogenesis, the molecular mechanisms behind this association is not clear yet. Seladin-1 is an enzyme catalyzing the last step in cholesterol biosynthesis converting desmosterol to cholesterol. The neuroprotective function of seladin-1 has gained interest in AD research recently. Seladin-1 has anti-apoptotic properties and regulates the expression of ß-secretase (BACE-1). Here we measured seladin-1 mRNA and protein expressions in rat primary cultured neurons under diabetic conditions and also in the brains of rats with streptozotocine (STZ)-induced diabetes. We show that constant lack of insulin for 5days decreased seladin-1 levels in cultured rat primary neurons. Similarly, a decrease in seladin-1 was found in the brains of rats with STZ-induced diabetes. However, if the lack of insulin and/or high glucose treatment was intermittent, neuronal seladin-1 levels were not affected in vitro. On the other hand, treatment of neurons with metformin resulted in a significant increase in seladin-1. Constant lack of insulin for 5days, as well as high glucose treatment, increased the neuronal expression of BACE-1 in vitro, but not in the in vivo model. Our study defines insulin as a regulator of seladin-1 expression for the first time. The relevance of these findings for the association of DM with AD is discussed.
[Mh] Termos MeSH primário: Córtex Cerebral/metabolismo
Diabetes Mellitus Experimental/metabolismo
Insulina/deficiência
Proteínas do Tecido Nervoso/metabolismo
Neurônios/metabolismo
Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo
[Mh] Termos MeSH secundário: Secretases da Proteína Precursora do Amiloide/metabolismo
Animais
Ácido Aspártico Endopeptidases/metabolismo
Células Cultivadas
Desmosterol/metabolismo
Hiperglicemia/metabolismo
Cultura Primária de Células
Ratos
Estreptozocina
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Insulin); 0 (Nerve Tissue Proteins); 313-04-2 (Desmosterol); 5W494URQ81 (Streptozocin); EC 1.3.- (Oxidoreductases Acting on CH-CH Group Donors); EC 1.3.1.- (seladin-1 protein, rat); EC 3.4.- (Amyloid Precursor Protein Secretases); EC 3.4.23.- (Aspartic Acid Endopeptidases); EC 3.4.23.46 (Bace protein, rat)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171101
[Lr] Data última revisão:
171101
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160919
[St] Status:MEDLINE


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[PMID]:27128812
[Au] Autor:Villareal VA; Fu D; Costello DA; Xie XS; Yang PL
[Ad] Endereço:Department of Microbiology and Immunobiology, Harvard Medical School , 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States.
[Ti] Título:Hepatitis C Virus Selectively Alters the Intracellular Localization of Desmosterol.
[So] Source:ACS Chem Biol;11(7):1827-33, 2016 Jul 15.
[Is] ISSN:1554-8937
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Hepatitis C virus (HCV) increases intracellular desmosterol without affecting the steady-state abundance of other sterols, and the antiviral activity of inhibitors of desmosterol synthesis is suppressed by the addition of exogenous desmosterol. These observations suggest a model in which desmosterol has a specific function, direct or indirect, in HCV replication and that HCV alters desmosterol homeostasis to promote viral replication. Here, we use stimulated Raman scattering (SRS) microscopy in combination with isotopically labeled sterols to show that HCV causes desmosterol to accumulate in lipid droplets that are closely associated with the viral NS5A protein and that are visually distinct from the broad distribution of desmosterol in mock-infected cells and the more heterogeneous and disperse lipid droplets to which cholesterol traffics. Localization of desmosterol in NS5A-associated lipid droplets suggests that desmosterol may affect HCV replication via a direct mechanism. We anticipate that SRS microscopy and similar approaches can provide much needed tools to study the localization of specific lipid molecules in cellulo and in vivo.
[Mh] Termos MeSH primário: Desmosterol/metabolismo
Hepacivirus/fisiologia
[Mh] Termos MeSH secundário: Linhagem Celular Tumoral
Homeostase
Seres Humanos
Microscopia de Fluorescência
Replicação Viral
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
313-04-2 (Desmosterol)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170715
[Lr] Data última revisão:
170715
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160430
[St] Status:MEDLINE
[do] DOI:10.1021/acschembio.6b00324


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[PMID]:26968128
[Au] Autor:Zhao Q; Qian C; Chen XZ
[Ad] Endereço:College of Chemical and Biological Engineering, Zhejiang University; Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University, Hangzhou 310027, China.
[Ti] Título:A highly stereoselective synthesis of C-24 and C-25 oxysterols from desmosterol.
[So] Source:Steroids;109:16-21, 2016 May.
[Is] ISSN:1878-5867
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A new highly stereoselective construction of the side chain of the C-24 and C-25 oxysterols has been achieved by using desmosterol acetate as the starting material and an improved Sharpless catalytic asymmetric dihydroxylation with 100% d.e. (diastereomeric excess) as the key step. The result is much better than the usual asymmetric dihydroxylation procedure. t-Butyl nitrite/2,2,6,6-tetramethylpiperidine N-oxyl radical/FeCl3 catalyst system was developed to activate molecular oxygen for the aerobic oxidation of 24-hydroxycholesterol and the 24-ketocholesterol was obtained in 86.2% yield. The oxidation system has never been reported before. The mechanism for the catalytic aerobic oxidation was also proposed.
[Mh] Termos MeSH primário: Desmosterol/química
Oxisteróis/química
Oxisteróis/síntese química
[Mh] Termos MeSH secundário: Catálise
Técnicas de Química Sintética
Estereoisomerismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Oxysterols); 313-04-2 (Desmosterol)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160313
[St] Status:MEDLINE


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[PMID]:26577223
[Au] Autor:Andrade I; Santos L; Ramos F
[Ad] Endereço:Instituto Politécnico de Coimbra, ESTESC-Coimbra Health School, Ciências Complementares, Rua 5 Outubro, S. Martinho do Bispo, Apartado 7006, 3046-854 Coimbra, Portugal; CEF-Center for Pharmaceutical Studies, Health Sciences Campus, Pharmacy Faculty, University of Coimbra, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal.
[Ti] Título:Cholesterol absorption and synthesis markers in Portuguese hypercholesterolemic adults: A cross-sectional study.
[So] Source:Eur J Intern Med;28:85-90, 2016 Mar.
[Is] ISSN:1879-0828
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: The dynamics of cholesterol homeostasis and the development of cardiovascular disease (CVD) are complex and multifactorial, to which adds individual variability in the proportion of cholesterol from exogenous versus endogenous sources. The aim of this study was to undertake the first characterization of cholesterol absorption and synthesis profiles in Portuguese hypercholesterolemic adults through the quantification of surrogate markers, and the analysis of the predictive value of age and sex on the cholesterol homeostasis biomarkers. METHODS: Serum samples for the measurement of lipid profiles and cholesterol homeostasis markers were obtained for 100 men and 112 women, aged 30-65, with TC ≥ 5.2 mmol/L (~200mg/dL) and/or LDL-C ≥ 2.6 mmol/L (~100mg/dL), none of whom were on any lipid-lowering therapy. RESULTS: Overall, sex-specific significant differences were observed in the cholesterol homeostasis markers and lipid profiles; women had lower cholesterol synthesis marker concentrations (P<0.01 for lathosterol) and lipid parameters (except for HDL-C concentrations). Age-related significant differences were also found, including higher concentrations of cholesterol absorption markers in association with increasing age. CONCLUSION: In our study, the predictors of higher levels of cholesterol absorption markers were higher age and female gender.
[Mh] Termos MeSH primário: HDL-Colesterol/sangue
LDL-Colesterol/sangue
Dieta
Hipercolesterolemia/sangue
[Mh] Termos MeSH secundário: Adulto
Fatores Etários
Idoso
Biomarcadores/sangue
Colestanol/sangue
Colesterol/análogos & derivados
Colesterol/sangue
Colesterol/metabolismo
Estudos Transversais
Desmosterol/sangue
Feminino
Homeostase
Seres Humanos
Masculino
Meia-Idade
Fitosteróis/sangue
Portugal
Fatores Sexuais
Sitosteroides/sangue
Triglicerídeos/sangue
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biomarkers); 0 (Cholesterol, HDL); 0 (Cholesterol, LDL); 0 (Phytosterols); 0 (Sitosterols); 0 (Triglycerides); 313-04-2 (Desmosterol); 5L5O665639 (campesterol); 5LI01C78DD (gamma-sitosterol); 80-99-9 (lathosterol); 8M308U816E (Cholestanol); 97C5T2UQ7J (Cholesterol)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151119
[St] Status:MEDLINE


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[PMID]:26368000
[Au] Autor:Benesch MG; Lewis RN; McElhaney RN
[Ad] Endereço:Department of Biochemistry, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
[Ti] Título:A calorimetric and spectroscopic comparison of the effects of cholesterol and its immediate biosynthetic precursors 7-dehydrocholesterol and desmosterol on the thermotropic phase behavior and organization of dipalmitoylphosphatidylcholine bilayer membranes.
[So] Source:Chem Phys Lipids;191:123-35, 2015 Oct.
[Is] ISSN:1873-2941
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:We performed differential scanning calorimetric (DSC) and Fourier transform infrared (FTIR) spectroscopic studies of the effects of cholesterol (CHOL), 7-dehydrocholeterol (7DHC) and desmosterol (DES) on the thermotropic phase behavior and organization of dipalmitoylphosphatidylcholine (DPPC) bilayer membranes. 7DHC and DES are the immediate biosynthetic precursors of CHOL in the Kandutch-Russell and Bloch pathways and 7DHC and DES differ in structure from CHOL only by the presence of an additional double bond at C7 of ring B or C24 of the alkyl side chain, respectively. Our DSC results indicate that the incorporation of all three sterols produces comparable decreases in the temperature of the pretransition of DPPC, but CHOL decreases its cooperativity and enthalpy more strongly than 7DHC and especially DES. These findings indicate that all three sterols decrease the thermal stability of gel phase DPPC bilayers but that 7DHC and especially DES are less miscible in them. However, the incorporation of CHOL and DES produce comparable increases in the temperature of the broad component of the main phase transition of DPPC while 7DHC decreases it, but again CHOL produces greater decreases in its cooperativity and enthalpy then 7DHC and especially DES. These results indicate that CHOL and DES stabilize the sterol-rich domains of fluid DPPC bilayers, but that 7DHC and especially DES are less miscible in them. Our FTIR spectroscopic results indicate that CHOL increases the rotational conformational order of fluid DPPC bilayers to a somewhat and markedly greater degree than DES and 7DHC, respectively, consistent with our DSC findings. Our spectroscopic results also indicate that although all three sterols produce comparable degrees of H-bonding (hydration) of the DPPC ester carbonyl groups in fluid bilayers, CHOL is again found to be fully soluble in gel state DPPC bilayers at low temperatures, whereas 7DHC and especially DES are not. In general, we find that 7DHC and DES incorporation produce considerably different effects on DPPC bilayer membranes. In particular, the presence of an additional double bond at C7 or C24 produces a marked reduction in the ability of 7DHC to order fluid DPPC bilayers and in the miscibility of DES in such bilayers, respectively. These different effects may be the biophysical basis for the reduction of these double bonds in the last steps of CHOL biosynthesis, and for the deleterious biological effects of the accumulation of these sterols in vivo.
[Mh] Termos MeSH primário: Colesterol/química
Desidrocolesteróis/química
Desmosterol/química
Bicamadas Lipídicas/química
[Mh] Termos MeSH secundário: 1,2-Dipalmitoilfosfatidilcolina/química
Varredura Diferencial de Calorimetria
Bicamadas Lipídicas/metabolismo
Transição de Fase
Espectroscopia de Infravermelho com Transformada de Fourier
Termodinâmica
Temperatura de Transição
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Dehydrocholesterols); 0 (Lipid Bilayers); 2644-64-6 (1,2-Dipalmitoylphosphatidylcholine); 313-04-2 (Desmosterol); 97C5T2UQ7J (Cholesterol); BK1IU07GKF (7-dehydrocholesterol)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:151104
[Lr] Data última revisão:
151104
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150915
[St] Status:MEDLINE


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[PMID]:25960185
[Au] Autor:Hac-Wydro K; Weder K; Mach M; Flasinski M; Wydro P
[Ad] Endereço:Department of Environmental Chemistry, Faculty of Chemistry, Jagiellonian University, Gronostajowa 3, 30-387 Kraków, Poland. Electronic address: hac@chemia.uj.edu.pl.
[Ti] Título:The influence of cholesterol precursor--desmosterol--on artificial lipid membranes.
[So] Source:Biochim Biophys Acta;1848(8):1639-45, 2015 Aug.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The disorders in cholesterol biosynthesis pathway and various diseases manifest in the accumulation of cholesterol precursors in the human tissues and cellular membranes. In this paper the effect of desmosterol--one of cholesterol precursors--on model lipid membranes was studied. The investigations were performed for binary SM/desmo and POPC/desmo and ternary SM/POPC/desmo monolayers. Moreover, the experiments based on the gradual substitution of cholesterol by desmosterol in SM/POPC/chol=1:1:1 system were done. The obtained results allowed one to conclude that desmosterol is of lower domains promoting and stabilizing properties and packs less tightly with the lipids in monolayers. Moreover, desmosterol probably could replace cholesterol in model membranes, but only at its low proportion in the system (2%), however, at a higher degree of cholesterol substitution a significant decrease of the monolayer stability and packing and alterations in the film morphology were detected. The results collected in this work together with those from previous experiments allowed one to analyze the effect of a double bond in the sterol side chain as well as its position in the ring system on membrane activity of the molecule and to verify Bloch hypothesis.
[Mh] Termos MeSH primário: Desmosterol/química
Bicamadas Lipídicas
Membranas Artificiais
[Mh] Termos MeSH secundário: Colesterol/química
Desmosterol/metabolismo
Estrutura Molecular
Fosfatidilcolinas/química
Esfingomielinas/química
Relação Estrutura-Atividade
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Lipid Bilayers); 0 (Membranes, Artificial); 0 (Phosphatidylcholines); 0 (Sphingomyelins); 313-04-2 (Desmosterol); 97C5T2UQ7J (Cholesterol); PU2755PT4O (zymosterol); TE895536Y5 (1-palmitoyl-2-oleoylphosphatidylcholine)
[Em] Mês de entrada:1509
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150512
[St] Status:MEDLINE


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[PMID]:25847673
[Au] Autor:Altunayar C; Sahin I; Kazanci N
[Ad] Endereço:Department of Physics, Faculty of Science, Ege University, 35100 Bornova, Izmir, Turkey. Electronic address: cisemaltunayar@gmail.com.
[Ti] Título:A comparative study of the effects of cholesterol and desmosterol on zwitterionic DPPC model membranes.
[So] Source:Chem Phys Lipids;188:37-45, 2015 May.
[Is] ISSN:1873-2941
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:Desmosterol is a direct biosynthetic precursor of cholesterol in Bloch biochemical pathway of cholesterol biosynthesis and differs with cholesterol only by a double bond in carbon 24. In this study, we aimed to research for the first time comparative effects of cholesterol and its precursor desmosterol on dipalmitoyl phosphatidylcholine (DPPC) multilamellar vesicles (MLVs) by utilizing Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). Our DSC studies reveal that with the addition of increasing desmosterol and cholesterol concentrations into pure DPPC MLVs, the pretransition disappears, the main phase transition shifts to lower temperatures and then disappears. While the main phase transition is abolished at 25 mol% concentration of desmosterol, this disappearance of the main phase transition occurs at cholesterol concentration above 30 mol%. Our FTIR studies show that both desmosterol and cholesterol decrease the order in the gel phase, whereas they increase it in the liquid crystalline phase. Importantly, we found that the effect of desmosterol on membrane order is weaker than that of cholesterol in both phases. Moreover, desmosterol and cholesterol increase the dynamics of DPPC membranes in the gel phase, while they decrease it in the liquid crystalline phase. Both sterols also induce a decrease in the wavenumber values of the C=O stretching and PO2(-) antisymmetric double stretching bands of DPPC both in the gel and liquid crystalline phases, which points out hydrogen bonding in between the hydroxyl group of both sterols and the carbonyl and phosphate groups of DPPC membranes.
[Mh] Termos MeSH primário: 1,2-Dipalmitoilfosfatidilcolina/química
Colesterol/química
Desmosterol/química
Bicamadas Lipídicas/química
[Mh] Termos MeSH secundário: Modelos Moleculares
Estrutura Molecular
Transição de Fase
Espectroscopia de Infravermelho com Transformada de Fourier
Temperatura Ambiente
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Lipid Bilayers); 2644-64-6 (1,2-Dipalmitoylphosphatidylcholine); 313-04-2 (Desmosterol); 97C5T2UQ7J (Cholesterol)
[Em] Mês de entrada:1602
[Cu] Atualização por classe:150604
[Lr] Data última revisão:
150604
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150408
[St] Status:MEDLINE


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[PMID]:25558972
[Au] Autor:Hu X; Wang Y; Hao LY; Liu X; Lesch CA; Sanchez BM; Wendling JM; Morgan RW; Aicher TD; Carter LL; Toogood PL; Glick GD
[Ad] Endereço:Lycera Corp, Ann Arbor, Michigan, USA.
[Ti] Título:Sterol metabolism controls T(H)17 differentiation by generating endogenous RORγ agonists.
[So] Source:Nat Chem Biol;11(2):141-7, 2015 Feb.
[Is] ISSN:1552-4469
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Retinoic acid receptor-related orphan receptor γ (RORγt) controls the differentiation of naive CD4(+) T cells into the TH17 lineage, which are critical cells in the pathogenesis of autoimmune diseases. Here we report that during TH17 differentiation, cholesterol biosynthesis and uptake programs are induced, whereas their metabolism and efflux programs are suppressed. These changes result in the accumulation of the cholesterol precursor, desmosterol, which functions as a potent endogenous RORγ agonist. Generation of cholesterol precursors is essential for TH17 differentiation as blocking cholesterol synthesis with chemical inhibitors at steps before the formation of active precursors reduces differentiation. Upon activation, metabolic changes also lead to production of specific sterol-sulfate conjugates that favor activation of RORγ over the TH17-inhibiting sterol receptor LXR. Thus, TH17 differentiation is orchestrated by coordinated sterol synthesis, mobilization and metabolism to selectively activate RORγ.
[Mh] Termos MeSH primário: Diferenciação Celular/fisiologia
Colesterol/metabolismo
Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas
Células Th17/citologia
[Mh] Termos MeSH secundário: Animais
Linfócitos T CD4-Positivos/citologia
Linhagem da Célula
Colesterol/biossíntese
Colesterol/química
Desmosterol/análogos & derivados
Desmosterol/química
Desmosterol/metabolismo
Interleucina-17/biossíntese
Camundongos Endogâmicos BALB C
Camundongos Endogâmicos C57BL
Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética
Células Sf9
Spodoptera
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Interleukin-17); 0 (Nuclear Receptor Subfamily 1, Group F, Member 3); 313-04-2 (Desmosterol); 97C5T2UQ7J (Cholesterol)
[Em] Mês de entrada:1504
[Cu] Atualização por classe:170603
[Lr] Data última revisão:
170603
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150107
[St] Status:MEDLINE
[do] DOI:10.1038/nchembio.1714


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[PMID]:25476366
[Au] Autor:Mendiara I; Bentayeb K; Nerín C; Domeño C
[Ad] Endereço:Department of Analytical Chemistry, EINA-University of Zaragoza, María de Luna St. 3, E-50018 Zaragoza, Spain. Electronic address: isabelmn@unizar.es.
[Ti] Título:Online solid-phase extraction-liquid chromatography-mass spectrometry to determine free sterols in human serum.
[So] Source:Talanta;132:690-7, 2015 Jan.
[Is] ISSN:1873-3573
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:An automated method for analyzing free non-cholesterol sterols in human serum using online solid phase extraction-liquid chromatography-mass spectrometry is proposed herein. The method allows the determination of three phytosterols (sitosterol, stigmasterol and campesterol) and two cholesterol precursors (desmosterol and lanosterol). The analysis of sterols in human serum is critical in the study of cholesterol-related disorders, such as inherited familial hypercholesterolemias. Special effort was made to isolate the analytes from the serum lipoproteins, their natural conveyance through the bloodstream. The sample treatment consisted of a Bligh-Dyer extraction followed by dilution of the extract. This treatment allowed the sample to be injected into the online system and ensured the correct detection of the analytes, while avoiding the matrix effects commonly related to serum samples. The analytical performance showed linear ranges that covered two orders of magnitude, with correlation coefficients above 0.99. Limits of detection and quantification ranged from 0.2 ng/mL to 13 ng/mL and from 1.0 ng/mL to 43 ng/mL, respectively. Recovery when spiking serum with a half or a tenth of the average concentration reported in human serum ranged from 99% to 111% and from 102% to 120%, respectively. Intra-day precision and inter-day precision were below 20%.
[Mh] Termos MeSH primário: Colesterol/análogos & derivados
Desmosterol/sangue
Lanosterol/sangue
Fitosteróis/sangue
Sitosteroides/sangue
Estigmasterol/sangue
[Mh] Termos MeSH secundário: Colesterol/sangue
Colesterol/isolamento & purificação
Cromatografia Líquida
Desmosterol/isolamento & purificação
Seres Humanos
Lanosterol/isolamento & purificação
Limite de Detecção
Espectrometria de Massas
Fitosteróis/isolamento & purificação
Sitosteroides/isolamento & purificação
Extração em Fase Sólida/métodos
Estigmasterol/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Phytosterols); 0 (Sitosterols); 1J05Z83K3M (Lanosterol); 313-04-2 (Desmosterol); 5L5O665639 (campesterol); 5LI01C78DD (gamma-sitosterol); 97C5T2UQ7J (Cholesterol); 99WUK5D0Y8 (Stigmasterol)
[Em] Mês de entrada:1508
[Cu] Atualização por classe:141205
[Lr] Data última revisão:
141205
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141206
[St] Status:MEDLINE



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