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Teng YC, Gielen MC, de Gruijter NM, Ciurtin C, Rosser EC, Karu K. Phytosterols in human serum as measured using a liquid chromatography tandem mass spectrometry. J Steroid Biochem Mol Biol 2024; 241:106519. [PMID: 38614432 DOI: 10.1016/j.jsbmb.2024.106519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 04/05/2024] [Accepted: 04/09/2024] [Indexed: 04/15/2024]
Abstract
Phytosterols are lipophilic compounds found in plants with structural similarity to mammalian cholesterol. They cannot be endogenously produced by mammals and therefore always originate from diet. There has been increased interest in dietary phytosterols over the last few decades due to their association with a variety of beneficial health effects including low-density lipoprotein cholesterol lowering, anti-inflammatory and anti-cancerous effects. They are proposed as potential moderators for diseases associated with the central nervous system where cholesterol homeostasis is found to be imperative (multiple sclerosis, dementia, etc.) due to their ability to reach the brain. Here we utilised an enzyme-assisted derivatisation for sterol analysis (EADSA) in combination with a liquid chromatography tandem mass spectrometry (LC-MSn) to characterise phytosterol content in human serum. As little as 100 fg of plant sterol was injected on a reversed phase LC column. The method allows semi-quantitative measurements of phytosterols and their derivatives simultaneously with measurement of cholesterol metabolites. The identification of phytosterols in human serum was based on comparison of their LC retention times and MS2, MS3 spectra with a library of authentic standards. Free campesterol serum concentration was in the range from 0.30-4.10 µg/mL, β-sitosterol 0.16-3.37 µg/mL and fucosterol was at lowest concentration range from 0.05-0.38 µg/mL in ten individuals. This analytical methodology could be applied to the analysis of other biological fluids and tissues.
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Affiliation(s)
- Yu Chun Teng
- UCL Chemistry Mass Spectrometry Facility, 20 Gordon Street, University College London, London, United Kingdom
| | - Marie Claire Gielen
- UCL Chemistry Mass Spectrometry Facility, 20 Gordon Street, University College London, London, United Kingdom
| | - Nina M de Gruijter
- UCL Chemistry Mass Spectrometry Facility, 20 Gordon Street, University College London, London, United Kingdom; Centre for Adolescent Rheumatology Versus Arthritis at University College London, University College London Hospital and Great Ormond Street Hospital, London, United Kingdom; Centre for Rheumatology Research, Division of Medicine, University College London, London, United Kingdom
| | - Coziana Ciurtin
- Centre for Adolescent Rheumatology Versus Arthritis at University College London, University College London Hospital and Great Ormond Street Hospital, London, United Kingdom; Centre for Rheumatology Research, Division of Medicine, University College London, London, United Kingdom
| | - Elizabeth C Rosser
- Centre for Adolescent Rheumatology Versus Arthritis at University College London, University College London Hospital and Great Ormond Street Hospital, London, United Kingdom; Centre for Rheumatology Research, Division of Medicine, University College London, London, United Kingdom
| | - Kersti Karu
- UCL Chemistry Mass Spectrometry Facility, 20 Gordon Street, University College London, London, United Kingdom.
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2
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Peeples ES, Mirnics K, Korade Z. Chemical Inhibition of Sterol Biosynthesis. Biomolecules 2024; 14:410. [PMID: 38672427 PMCID: PMC11048061 DOI: 10.3390/biom14040410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 03/22/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
Cholesterol is an essential molecule of life, and its synthesis can be inhibited by both genetic and nongenetic mechanisms. Hundreds of chemicals that we are exposed to in our daily lives can alter sterol biosynthesis. These also encompass various classes of FDA-approved medications, including (but not limited to) commonly used antipsychotic, antidepressant, antifungal, and cardiovascular medications. These medications can interfere with various enzymes of the post-lanosterol biosynthetic pathway, giving rise to complex biochemical changes throughout the body. The consequences of these short- and long-term homeostatic disruptions are mostly unknown. We performed a comprehensive review of the literature and built a catalogue of chemical agents capable of inhibiting post-lanosterol biosynthesis. This process identified significant gaps in existing knowledge, which fall into two main areas: mechanisms by which sterol biosynthesis is altered and consequences that arise from the inhibitions of the different steps in the sterol biosynthesis pathway. The outcome of our review also reinforced that sterol inhibition is an often-overlooked mechanism that can result in adverse consequences and that there is a need to develop new safety guidelines for the use of (novel and already approved) medications with sterol biosynthesis inhibiting side effects, especially during pregnancy.
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Affiliation(s)
- Eric S. Peeples
- Department of Pediatrics, University of Nebraska Medical Center, Omaha, NE 68198, USA;
- Child Health Research Institute, Omaha, NE 68198, USA;
- Division of Neonatology, Children’s Nebraska, Omaha, NE 68114, USA
| | - Karoly Mirnics
- Child Health Research Institute, Omaha, NE 68198, USA;
- Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Pharmacology & Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Munroe-Meyer Institute, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Zeljka Korade
- Department of Pediatrics, University of Nebraska Medical Center, Omaha, NE 68198, USA;
- Child Health Research Institute, Omaha, NE 68198, USA;
- Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
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3
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De La Fuente DC, Tamburini C, Stonelake E, Andrews R, Hall J, Owen MJ, Linden DEJ, Pocklington A, Li M. Impaired oxysterol-liver X receptor signaling underlies aberrant cortical neurogenesis in a stem cell model of neurodevelopmental disorder. Cell Rep 2024; 43:113946. [PMID: 38483902 DOI: 10.1016/j.celrep.2024.113946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 12/22/2023] [Accepted: 02/26/2024] [Indexed: 04/02/2024] Open
Abstract
The mechanisms by which genomic risks contribute to the onset of neuropsychiatric conditions remain a key challenge and a prerequisite for successful development of effective therapies. 15q11.2 copy number variation (CNV) containing the CYFIP1 gene is associated with autism and schizophrenia. Using stem cell models, we show that 15q11.2 deletion (15q11.2del) and CYFIP1 loss of function (CYFIP1-LoF) lead to premature neuronal differentiation, while CYFIP1 gain of function (CYFIP1-GoF) favors neural progenitor maintenance. CYFIP1 dosage changes led to dysregulated cholesterol metabolism and altered levels of 24S,25-epoxycholesterol, which can mimic the 15q11.2del and CYFIP1-LoF phenotypes by promoting cortical neuronal differentiation and can restore the impaired neuronal differentiation of CYFIP1-GoF neural progenitors. Moreover, the neurogenic activity of 24S,25-epoxycholesterol is lost following genetic deletion of liver X receptor (LXRβ), while compound deletion of LXRβ in CYFIP1-/- background rescued their premature neurogenesis. This work delineates LXR-mediated oxysterol regulation of neurogenesis as a pathological mechanism in neural cells carrying 15q11.2 CNV and provides a potential target for therapeutic strategies for associated disorders.
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Affiliation(s)
| | - Claudia Tamburini
- Neuroscience and Mental Health Innovation Institute, Cardiff University, Cardiff, UK
| | | | - Robert Andrews
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - Jeremy Hall
- Neuroscience and Mental Health Innovation Institute, Cardiff University, Cardiff, UK; Division of Psychiatry and Clinical Neuroscience, Cardiff University, Cardiff, UK
| | - Michael J Owen
- Neuroscience and Mental Health Innovation Institute, Cardiff University, Cardiff, UK; Division of Psychiatry and Clinical Neuroscience, Cardiff University, Cardiff, UK
| | - David E J Linden
- Neuroscience and Mental Health Innovation Institute, Cardiff University, Cardiff, UK; Division of Psychiatry and Clinical Neuroscience, Cardiff University, Cardiff, UK; School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, the Netherlands
| | - Andrew Pocklington
- Division of Psychiatry and Clinical Neuroscience, Cardiff University, Cardiff, UK
| | - Meng Li
- Neuroscience and Mental Health Innovation Institute, Cardiff University, Cardiff, UK; Division of Psychiatry and Clinical Neuroscience, Cardiff University, Cardiff, UK; School of Bioscience, Cardiff University, Cardiff, UK.
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4
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da Costa LCO, Gardinassi LG, Veras FP, Milanezi C, Ramalho LNZ, Benevides L, Alves-Filho JC, da Silva JS, da Silva Souza C. Expression of B lymphocyte-induced maturation protein 1 (Blimp-1) in keratinocyte and cytokine signalling drives human Th17 response in psoriasis. Arch Dermatol Res 2023; 315:481-490. [PMID: 36042041 DOI: 10.1007/s00403-022-02379-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 06/30/2022] [Accepted: 08/01/2022] [Indexed: 11/02/2022]
Abstract
Transcriptional factor B lymphocyte-induced maturation protein 1 (Blimp-1) is pivotally implicated in T helper 17 (Th17) cell differentiation. This study investigated expression of the Blimp-1 protein, positive regulatory domain 1 (PRDM1), and cytokine genes in psoriasis (PsO). Affected (AS-PsO) and non-affected skin (nAS-PsO) samples were used to assess gene and protein expressions by reverse transcription-quantitative PCR (RT-qPCR), and immunostaining and confocal microscopy, respectively; the normalised public transcriptomic data permitted differential gene expression analyses. On RT-qPCR, PRDM1 and IL17A transcripts showed higher expression in AS-PsO than in nAS-PsO (n = 34) (p < 0.001; p < 0.0001, respectively). Confocal microscopy showed Blimp-1 protein expression in epidermal layer keratinocytes in AS-PsO, but not in nAS-PsO. Bioinformatic analysis of the transcriptomic dataset GSE13355 corroborated the increased PRDM1, signal transducer and activator of transcription 3 (STAT3), IL12B, TNF, IL17A, IL6, IL1B, IL22, and IL10 gene expression in AS-PsO, when compared to normal skin and nAS-PsO (p < 0.001). PRDM1 expression correlated positively (p < 0.0001) with that of IL17A (r = 0.7), IL1B (r = 0.67), IL12B (r = 0.6), IL6 (r = 0.59), IL22 (r = 0.53), IL23A (r = 0.47), IL21 (r = 0.47), IL27 (r = 0.34), IL23R (r = 0.32), S100 calcium binding protein A9 (r = 0.63), and lipocalin 2 (r = 0.50), and negatively with that of TGFB1 (r = - 0.28) and RORC (r = - 0.60). Blimp-1 may be critical in the pathogenesis of PsO dysregulation involving the Th17 inflammatory pathway. This knowledge may accelerate the development of new treatments.
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Affiliation(s)
- Lorena Carla Oliveira da Costa
- Dermatology Division, Department of Internal Medicine, Ribeirão Preto Medical School, Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, Monte Alegre, Ribeirão Preto, São Paulo, 14048-900, Brazil
| | - Luiz Gustavo Gardinassi
- Department of Biosciences and Technology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Flávio Protásio Veras
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Cristiane Milanezi
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | | | - Luciana Benevides
- Fiocruz-Bi-Institutional Translational Medicine Plataform, Ribeirão Preto, São Paulo, Brazil
| | - José Carlos Alves-Filho
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - João Santana da Silva
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
- Fiocruz-Bi-Institutional Translational Medicine Plataform, Ribeirão Preto, São Paulo, Brazil
| | - Cacilda da Silva Souza
- Dermatology Division, Department of Internal Medicine, Ribeirão Preto Medical School, Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, Monte Alegre, Ribeirão Preto, São Paulo, 14048-900, Brazil.
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5
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Wang Y, Yutuc E, Griffiths WJ. Cholesterol metabolism pathways - are the intermediates more important than the products? FEBS J 2021; 288:3727-3745. [PMID: 33506652 PMCID: PMC8653896 DOI: 10.1111/febs.15727] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/04/2021] [Accepted: 01/25/2021] [Indexed: 12/25/2022]
Abstract
Every cell in vertebrates possesses the machinery to synthesise cholesterol and to metabolise it. The major route of cholesterol metabolism is conversion to bile acids. Bile acids themselves are interesting molecules being ligands to nuclear and G protein‐coupled receptors, but perhaps the intermediates in the bile acid biosynthesis pathways are even more interesting and equally important. Here, we discuss the biological activity of the different intermediates generated in the various bile acid biosynthesis pathways. We put forward the hypothesis that the acidic pathway of bile acid biosynthesis has primary evolved to generate signalling molecules and its utilisation by hepatocytes provides an added bonus of producing bile acids to aid absorption of lipids in the intestine.
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Wang Y, Yutuc E, Griffiths WJ. Neuro-oxysterols and neuro-sterols as ligands to nuclear receptors, GPCRs, ligand-gated ion channels and other protein receptors. Br J Pharmacol 2020; 178:3176-3193. [PMID: 32621622 DOI: 10.1111/bph.15191] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/16/2020] [Accepted: 06/21/2020] [Indexed: 12/13/2022] Open
Abstract
The brain is the most cholesterol rich organ in the body containing about 25% of the body's free cholesterol. Cholesterol cannot pass the blood-brain barrier and be imported or exported; instead, it is synthesised in situ and metabolised to oxysterols, oxidised forms of cholesterol, which can pass the blood-brain barrier. 24S-Hydroxycholesterol is the dominant oxysterol in the brain after parturition, but during development, a myriad of other oxysterols are produced, which persist as minor oxysterols after birth. During both development and in later life, sterols and oxysterols interact with a variety of different receptors, including nuclear receptors, membrane bound GPCRs, the oxysterol/sterol sensing proteins INSIG and SCAP, and the ligand-gated ion channel NMDA receptors found in nerve cells. In this review, we summarise the different oxysterols and sterols found in the CNS whose biological activity is transmitted via these different classes of protein receptors. LINKED ARTICLES: This article is part of a themed issue on Oxysterols, Lifelong Health and Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.16/issuetoc.
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Affiliation(s)
- Yuqin Wang
- Swansea University Medical School, Swansea, UK
| | - Eylan Yutuc
- Swansea University Medical School, Swansea, UK
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7
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Jia M, Peng Z, Yang K, Su C, Wang Y, Yan C. A high-throughput targeted metabolomics method for the quantification of 104 non-polar metabolites in cholesterol, eicosanoid, and phospholipid metabolism: application in the study of a CCl4-induced liver injury mouse model. Analyst 2020; 145:3575-3591. [PMID: 32329491 DOI: 10.1039/d0an00385a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Experimental workflow of 104 non-polar metabolites in cholesterol, eicosanoid, and phospholipid metabolisms analysis using UPLC-QqQ-MS.
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Affiliation(s)
- Mengqi Jia
- School of Pharmacy
- Shanghai Jiao Tong University
- Shanghai
- China
| | - Zhangxiao Peng
- Department of Molecular Oncology
- Eastern Hepatobiliary Surgical Hospital & National Centre for Liver Cancer
- Second Military Medical University
- Shanghai 200438
- China
| | - Kaige Yang
- School of Pharmacy
- Shanghai Jiao Tong University
- Shanghai
- China
| | - Changqing Su
- Department of Molecular Oncology
- Eastern Hepatobiliary Surgical Hospital & National Centre for Liver Cancer
- Second Military Medical University
- Shanghai 200438
- China
| | - Yan Wang
- School of Pharmacy
- Shanghai Jiao Tong University
- Shanghai
- China
| | - Chao Yan
- School of Pharmacy
- Shanghai Jiao Tong University
- Shanghai
- China
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8
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Griffiths WJ, Yutuc E, Abdel-Khalik J, Crick PJ, Hearn T, Dickson A, Bigger BW, Hoi-Yee Wu T, Goenka A, Ghosh A, Jones SA, Covey DF, Ory DS, Wang Y. Metabolism of Non-Enzymatically Derived Oxysterols: Clues from sterol metabolic disorders. Free Radic Biol Med 2019; 144:124-133. [PMID: 31009661 PMCID: PMC6863434 DOI: 10.1016/j.freeradbiomed.2019.04.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/12/2019] [Accepted: 04/16/2019] [Indexed: 12/18/2022]
Abstract
Cholestane-3β,5α,6β-triol (3β,5α,6β-triol) is formed from cholestan-5,6-epoxide (5,6-EC) in a reaction catalysed by cholesterol epoxide hydrolase, following formation of 5,6-EC through free radical oxidation of cholesterol. 7-Oxocholesterol (7-OC) and 7β-hydroxycholesterol (7β-HC) can also be formed by free radical oxidation of cholesterol. Here we investigate how 3β,5α,6β-triol, 7-OC and 7β-HC are metabolised to bile acids. We show, by monitoring oxysterol metabolites in plasma samples rich in 3β,5α,6β-triol, 7-OC and 7β-HC, that these three oxysterols fall into novel branches of the acidic pathway of bile acid biosynthesis becoming (25R)26-hydroxylated then carboxylated, 24-hydroxylated and side-chain shortened to give the final products 3β,5α,6β-trihydroxycholanoic, 3β-hydroxy-7-oxochol-5-enoic and 3β,7β-dihydroxychol-5-enoic acids, respectively. The intermediates in these pathways may be causative of some phenotypical features of, and/or have diagnostic value for, the lysosomal storage diseases, Niemann Pick types C and B and lysosomal acid lipase deficiency. Free radical derived oxysterols are metabolised in human to unusual bile acids via novel branches of the acidic pathway, intermediates in these pathways are observed in plasma.
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Affiliation(s)
- William J Griffiths
- Institute of Life Science, Swansea University Medical School, Singleton Park, Swansea, SA2 8PP, UK.
| | - Eylan Yutuc
- Institute of Life Science, Swansea University Medical School, Singleton Park, Swansea, SA2 8PP, UK
| | - Jonas Abdel-Khalik
- Institute of Life Science, Swansea University Medical School, Singleton Park, Swansea, SA2 8PP, UK
| | - Peter J Crick
- Institute of Life Science, Swansea University Medical School, Singleton Park, Swansea, SA2 8PP, UK
| | - Thomas Hearn
- Institute of Life Science, Swansea University Medical School, Singleton Park, Swansea, SA2 8PP, UK
| | - Alison Dickson
- Institute of Life Science, Swansea University Medical School, Singleton Park, Swansea, SA2 8PP, UK
| | - Brian W Bigger
- Stem Cell & Neurotherapies, Division of Cell Matrix Biology and Regenerative Medicine, Stopford Building, Oxford Road, University of Manchester, Manchester, M13 9PT, UK
| | - Teresa Hoi-Yee Wu
- Manchester Centre for Genomic Medicine, 6th Floor, St Mary's Hospital, Central Manchester Foundation Trust, University of Manchester, Oxford Road, Manchester, M13 9WL, UK
| | - Anu Goenka
- Manchester Centre for Genomic Medicine, 6th Floor, St Mary's Hospital, Central Manchester Foundation Trust, University of Manchester, Oxford Road, Manchester, M13 9WL, UK
| | - Arunabha Ghosh
- Manchester Centre for Genomic Medicine, 6th Floor, St Mary's Hospital, Central Manchester Foundation Trust, University of Manchester, Oxford Road, Manchester, M13 9WL, UK
| | - Simon A Jones
- Manchester Centre for Genomic Medicine, 6th Floor, St Mary's Hospital, Central Manchester Foundation Trust, University of Manchester, Oxford Road, Manchester, M13 9WL, UK
| | - Douglas F Covey
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - Daniel S Ory
- Diabetic Cardiovascular Disease Center, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Yuqin Wang
- Institute of Life Science, Swansea University Medical School, Singleton Park, Swansea, SA2 8PP, UK.
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9
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Theofilopoulos S, Abreu de Oliveira WA, Yang S, Yutuc E, Saeed A, Abdel-Khalik J, Ullgren A, Cedazo-Minguez A, Björkhem I, Wang Y, Griffiths WJ, Arenas E. 24( S),25-Epoxycholesterol and cholesterol 24S-hydroxylase ( CYP46A1) overexpression promote midbrain dopaminergic neurogenesis in vivo. J Biol Chem 2019; 294:4169-4176. [PMID: 30655290 PMCID: PMC6422085 DOI: 10.1074/jbc.ra118.005639] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 01/11/2019] [Indexed: 11/06/2022] Open
Abstract
The liver X receptors Lxrα/NR1H3 and Lxrβ/NR1H2 are ligand-dependent nuclear receptors critical for midbrain dopaminergic (mDA) neuron development. We found previously that 24(S),25-epoxycholesterol (24,25-EC), the most potent and abundant Lxr ligand in the developing mouse midbrain, promotes mDA neurogenesis in vitro In this study, we demonstrate that 24,25-EC promotes mDA neurogenesis in an Lxr-dependent manner in the developing mouse midbrain in vivo and also prevents toxicity induced by the Lxr inhibitor geranylgeranyl pyrophosphate. Furthermore, using MS, we show that overexpression of human cholesterol 24S-hydroxylase (CYP46A1) increases the levels of both 24(S)-hydroxycholesterol (24-HC) and 24,25-EC in the developing midbrain, resulting in a specific increase in mDA neurogenesis in vitro and in vivo, but has no effect on oculomotor or red nucleus neurogenesis. 24-HC, unlike 24,25-EC, did not affect in vitro neurogenesis, indicating that the neurogenic effect of 24,25-EC on mDA neurons is specific. Combined, our results indicate that increased levels of 24,25-EC in vivo, by intracerebroventricular delivery in WT mice or by overexpression of its biosynthetic enzyme CYP46A1, specifically promote mDA neurogenesis. We propose that increasing the levels of 24,25-EC in vivo may be a useful strategy to combat the loss of mDA neurons in Parkinson's disease.
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Affiliation(s)
- Spyridon Theofilopoulos
- From the Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden, .,the Regenerative Neurobiology Laboratory, Swansea University Medical School, Institute of Life Science 1, Singleton Park, Swansea SA2 8PP, United Kingdom
| | - Willy Antoni Abreu de Oliveira
- From the Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden
| | - Shanzheng Yang
- From the Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden
| | - Eylan Yutuc
- the Institute of Life Science, Swansea University Medical School, ILS1 Building, Singleton Park, Swansea SA2 8PP, United Kingdom
| | - Ahmed Saeed
- the Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital Huddinge, Stockholm 14157, Sweden, and
| | - Jonas Abdel-Khalik
- the Institute of Life Science, Swansea University Medical School, ILS1 Building, Singleton Park, Swansea SA2 8PP, United Kingdom
| | - Abbe Ullgren
- From the Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden.,the Center for Alzheimer Research, Department of Neurobiology Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Stockholm 14157, Sweden
| | - Angel Cedazo-Minguez
- the Center for Alzheimer Research, Department of Neurobiology Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Stockholm 14157, Sweden
| | - Ingemar Björkhem
- the Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital Huddinge, Stockholm 14157, Sweden, and
| | - Yuqin Wang
- the Institute of Life Science, Swansea University Medical School, ILS1 Building, Singleton Park, Swansea SA2 8PP, United Kingdom
| | - William J Griffiths
- the Institute of Life Science, Swansea University Medical School, ILS1 Building, Singleton Park, Swansea SA2 8PP, United Kingdom
| | - Ernest Arenas
- From the Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden,
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10
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Griffiths WJ, Gilmore I, Yutuc E, Abdel-Khalik J, Crick PJ, Hearn T, Dickson A, Bigger BW, Wu THY, Goenka A, Ghosh A, Jones SA, Wang Y. Identification of unusual oxysterols and bile acids with 7-oxo or 3β,5α,6β-trihydroxy functions in human plasma by charge-tagging mass spectrometry with multistage fragmentation. J Lipid Res 2018; 59:1058-1070. [PMID: 29626102 PMCID: PMC5983402 DOI: 10.1194/jlr.d083246] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 03/26/2018] [Indexed: 12/29/2022] Open
Abstract
7-Oxocholesterol (7-OC), 5,6-epoxycholesterol (5,6-EC), and its hydrolysis product cholestane-3β,5α,6β-triol (3β,5α,6β-triol) are normally minor oxysterols in human samples; however, in disease, their levels may be greatly elevated. This is the case in plasma from patients suffering from some lysosomal storage disorders, e.g., Niemann-Pick disease type C, or the inborn errors of sterol metabolism, e.g., Smith-Lemli-Opitz syndrome and cerebrotendinous xanthomatosis. A complication in the analysis of 7-OC and 5,6-EC is that they can also be formed ex vivo from cholesterol during sample handling in air, causing confusion with molecules formed in vivo. When formed endogenously, 7-OC, 5,6-EC, and 3β,5α,6β-triol can be converted to bile acids. Here, we describe methodology based on chemical derivatization and LC/MS with multistage fragmentation (MSn) to identify the necessary intermediates in the conversion of 7-OC to 3β-hydroxy-7-oxochol-5-enoic acid and 5,6-EC and 3β,5α,6β-triol to 3β,5α,6β-trihydroxycholanoic acid. Identification of intermediate metabolites is facilitated by their unusual MSn fragmentation patterns. Semiquantitative measurements are possible, but absolute values await the synthesis of isotope-labeled standards.
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Affiliation(s)
| | - Ian Gilmore
- Swansea University Medical School, Swansea SA2 8PP, Wales, United Kingdom
| | - Eylan Yutuc
- Swansea University Medical School, Swansea SA2 8PP, Wales, United Kingdom
| | - Jonas Abdel-Khalik
- Swansea University Medical School, Swansea SA2 8PP, Wales, United Kingdom
| | - Peter J Crick
- Swansea University Medical School, Swansea SA2 8PP, Wales, United Kingdom
| | - Thomas Hearn
- Swansea University Medical School, Swansea SA2 8PP, Wales, United Kingdom
| | - Alison Dickson
- Swansea University Medical School, Swansea SA2 8PP, Wales, United Kingdom
| | - Brian W Bigger
- Stem Cell and Neurotherapies, Division of Cell Matrix Biology and Regenerative Medicine, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Teresa Hoi-Yee Wu
- Manchester Centre for Genomic Medicine, St. Mary's Hospital, Central Manchester Foundation Trust, University of Manchester, Manchester M13 9WL, United Kingdom
| | - Anu Goenka
- Manchester Centre for Genomic Medicine, St. Mary's Hospital, Central Manchester Foundation Trust, University of Manchester, Manchester M13 9WL, United Kingdom
| | - Arunabha Ghosh
- Manchester Centre for Genomic Medicine, St. Mary's Hospital, Central Manchester Foundation Trust, University of Manchester, Manchester M13 9WL, United Kingdom
| | - Simon A Jones
- Manchester Centre for Genomic Medicine, St. Mary's Hospital, Central Manchester Foundation Trust, University of Manchester, Manchester M13 9WL, United Kingdom
| | - Yuqin Wang
- Swansea University Medical School, Swansea SA2 8PP, Wales, United Kingdom.
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11
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Griffiths WJ, Abdel-Khalik J, Crick PJ, Yutuc E, Wang Y. New methods for analysis of oxysterols and related compounds by LC-MS. J Steroid Biochem Mol Biol 2016; 162:4-26. [PMID: 26639636 DOI: 10.1016/j.jsbmb.2015.11.017] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Revised: 11/23/2015] [Accepted: 11/25/2015] [Indexed: 12/21/2022]
Abstract
Oxysterols are oxygenated forms of cholesterol or its precursors. They are formed enzymatically and via reactive oxygen species. Oxysterols are intermediates in bile acid and steroid hormone biosynthetic pathways and are also bioactive molecules in their own right, being ligands to nuclear receptors and also regulators of the processing of steroid regulatory element-binding proteins (SREBPs) to their active forms as transcription factors regulating cholesterol and fatty acid biosynthesis. Oxysterols are implicated in the pathogenesis of multiple disease states ranging from atherosclerosis and cancer to multiple sclerosis and other neurodegenerative diseases including Alzheimer's and Parkinson's disease. Analysis of oxysterols is challenging on account of their low abundance in biological systems in comparison to cholesterol, and due to the propensity of cholesterol to undergo oxidation in air to generate oxysterols with the same structures as those present endogenously. In this article we review the mass spectrometry-based methods for oxysterol analysis paying particular attention to analysis by liquid chromatography-mass spectrometry (LC-MS).
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Affiliation(s)
- William J Griffiths
- College of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
| | - Jonas Abdel-Khalik
- College of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK
| | - Peter J Crick
- College of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK
| | - Eylan Yutuc
- College of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK
| | - Yuqin Wang
- College of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
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12
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Higashi T, Ogawa S. Chemical derivatization for enhancing sensitivity during LC/ESI-MS/MS quantification of steroids in biological samples: a review. J Steroid Biochem Mol Biol 2016; 162:57-69. [PMID: 26454158 DOI: 10.1016/j.jsbmb.2015.10.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 09/29/2015] [Accepted: 10/02/2015] [Indexed: 01/22/2023]
Abstract
Sensitive and specific methods for the detection, characterization and quantification of endogenous steroids in body fluids or tissues are necessary for the diagnosis, pathological analysis and treatment of many diseases. Recently, liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) has been widely used for these purposes due to its specificity and versatility. However, the ESI efficiency and fragmentation behavior of some steroids are poor, which lead to a low sensitivity. Chemical derivatization is one of the most effective methods to improve the detection characteristics of steroids in ESI-MS/MS. Based on this background, this article reviews the recent advances in chemical derivatization for the trace quantification of steroids in biological samples by LC/ESI-MS/MS. The derivatization in ESI-MS/MS is based on tagging a proton-affinitive or permanently charged moiety on the target steroid. Introduction/formation of a fragmentable moiety suitable for the selected reaction monitoring by the derivatization also enhances the sensitivity. The stable isotope-coded derivatization procedures for the steroid analysis are also described.
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Affiliation(s)
- Tatsuya Higashi
- Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510, Japan.
| | - Shoujiro Ogawa
- Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510, Japan
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13
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Wang Y, Jiang H, Huang H, Xie Y, Zhao Y, You X, Tang L, Wang Y, Yin W, Qiu P, Yan G, Hu H. Determination of neuroprotective oxysterols in Calculus bovis
, human gallstones, and traditional Chinese medicine preparations by liquid chromatography with mass spectrometry. J Sep Sci 2015; 38:796-803. [DOI: 10.1002/jssc.201400850] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 12/05/2014] [Accepted: 12/10/2014] [Indexed: 01/15/2023]
Affiliation(s)
- Yalong Wang
- Lab of Pharmaceutics; School of Pharmaceutical Sciences; Sun Yat-sen University; Guangzhou China
| | - Han Jiang
- Lab of Pharmaceutics; School of Pharmaceutical Sciences; Sun Yat-sen University; Guangzhou China
| | - Huizhi Huang
- Lab of Pharmaceutics; School of Pharmaceutical Sciences; Sun Yat-sen University; Guangzhou China
| | - Yanqi Xie
- Lab of Pharmaceutics; School of Pharmaceutical Sciences; Sun Yat-sen University; Guangzhou China
| | - Yunshi Zhao
- Lab of Pharmaceutics; School of Pharmaceutical Sciences; Sun Yat-sen University; Guangzhou China
| | - Xiuhua You
- Lab of Pharmaceutics; School of Pharmaceutical Sciences; Sun Yat-sen University; Guangzhou China
| | - Lipeng Tang
- Department of Pharmacology; Zhongshan School of Medicine; Sun Yat-sen University; Guangzhou China
| | - Youqiong Wang
- Department of Pharmacology; Zhongshan School of Medicine; Sun Yat-sen University; Guangzhou China
| | - Wei Yin
- Department of Pharmacology; Zhongshan School of Medicine; Sun Yat-sen University; Guangzhou China
| | - Pengxin Qiu
- Department of Pharmacology; Zhongshan School of Medicine; Sun Yat-sen University; Guangzhou China
| | - Guangmei Yan
- Department of Pharmacology; Zhongshan School of Medicine; Sun Yat-sen University; Guangzhou China
| | - Haiyan Hu
- Lab of Pharmaceutics; School of Pharmaceutical Sciences; Sun Yat-sen University; Guangzhou China
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14
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Greninger AL. Picornavirus–Host Interactions to Construct Viral Secretory Membranes. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 129:189-212. [DOI: 10.1016/bs.pmbts.2014.10.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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15
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Wang Y, Karu K, Meljon A, Turton J, Yau JL, Seckl JR, Wang Y, Griffiths WJ. 24S,25-Epoxycholesterol in mouse and rat brain. Biochem Biophys Res Commun 2014; 449:229-34. [PMID: 24832732 PMCID: PMC4053837 DOI: 10.1016/j.bbrc.2014.05.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Accepted: 05/05/2014] [Indexed: 11/17/2022]
Abstract
24S,25-Epoxycholesterol identified and quantified in rodent brain. Knock out of Cyp27a1 leads to a decrease in 24S,25-epoxycholesterol. Knock out of Cyp7b1 leads to an increase in 24S,25-epoxycholesterol. 24S,25-Epoxycholesterol is metabolised by Cyp7b1 but not Cyp27a1.
24S,25-Epoxycholesterol is formed in a shunt of the mevalonate pathway that produces cholesterol. It is one of the most potent known activators of the liver X receptors and can inhibit sterol regulatory element-binding protein processing. Until recently analysis of 24S,25-epoxycholesterol at high sensitivity has been precluded by its thermal lability and lack of a strong chromophore. Here we report on the analysis of 24S,25-epoxycholesterol in rodent brain where its level was determined to be of the order of 0.4–1.4 μg/g wet weight in both adult mouse and rat. For comparison the level of 24S-hydroxycholesterol in brain of both rodents was of the order of 20 μg/g, while that of cholesterol in mouse was 10–20 mg/g. By exploiting knockout mice for the enzyme oxysterol 7α-hydroxylase (Cyp7b1) we show that this enzymes is important for the subsequent metabolism of the 24S,25-epoxide.
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Affiliation(s)
- Yuchen Wang
- Clinical Laboratory, Jinan Infectious Disease Hospital, Shandong University, Jinan, Shandong, China.
| | - Kersti Karu
- UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Anna Meljon
- Institute of Mass Spectrometry, College of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK
| | - John Turton
- UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Joyce L Yau
- Endocrinology Unit, BHF Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - Jonathan R Seckl
- Endocrinology Unit, BHF Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - Yuqin Wang
- Institute of Mass Spectrometry, College of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK
| | - William J Griffiths
- Institute of Mass Spectrometry, College of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
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16
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Meljon A, Wang Y, Griffiths WJ. Oxysterols in the brain of the cholesterol 24-hydroxylase knockout mouse. Biochem Biophys Res Commun 2014; 446:768-74. [PMID: 24491562 PMCID: PMC4000437 DOI: 10.1016/j.bbrc.2014.01.153] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 01/24/2014] [Indexed: 12/03/2022]
Abstract
24S-Hydroxycholesterol is almost absent from brain of the Cyp46a1−/− mouse. It is not quantitatively replaced by another oxysterol. Minor amounts of 22R-, 24R-, 25- and (25R),26-hydroxycholesterols are present. Cholesterol biosynthesis is reduced in brain of the Cyp46a1−/− mouse. 24S,25-Epoxycholesterol synthesis is reduced in brain of the Cyp46a1−/− mouse.
Oxysterols are oxidised forms of cholesterol or its precursors. In this study we utilised the cholesterol 24-hydroxylase knockout mouse (Cyp46a1−/−) to study the sterol and oxysterol content of brain. Despite a great reduction in the abundance of 24S-hydroxycholesterol, the dominant metabolite of cholesterol in wild type brain, no other cholesterol metabolite was found to quantitatively replace this oxysterol in the Cyp46a1−/− mouse. Only minor amounts of other side-chain oxysterols including 22R-, 24R-, 25- and (25R),26-hydroxycholesterols were detected. In line with earlier studies, levels of cholesterol were similar in Cyp46a1−/− and wild type animals. However, the level of the cholesterol precursor, desomsterol, and its parallel metabolite formed via a shut of the mevalonate pathway, 24S,25-epoxycholesterol, were reduced in the Cyp46a1−/− mouse. The reduction in abundance of 24S,25-epoxycholesterol is interesting in light of a recent report indicating that this oxysterol promotes dopaminergic neurogenesis.
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Affiliation(s)
- Anna Meljon
- Institute of Mass Spectrometry, College of Medicine, Swansea University, Singleton Park, Swansea SA2 8PP, UK
| | - Yuqin Wang
- Institute of Mass Spectrometry, College of Medicine, Swansea University, Singleton Park, Swansea SA2 8PP, UK
| | - William J Griffiths
- Institute of Mass Spectrometry, College of Medicine, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
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17
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Griffiths WJ, Crick PJ, Wang Y, Ogundare M, Tuschl K, Morris AA, Bigger BW, Clayton PT, Wang Y. Analytical strategies for characterization of oxysterol lipidomes: liver X receptor ligands in plasma. Free Radic Biol Med 2013; 59:69-84. [PMID: 22846477 DOI: 10.1016/j.freeradbiomed.2012.07.027] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 07/18/2012] [Accepted: 07/20/2012] [Indexed: 01/12/2023]
Abstract
Bile acids, bile alcohols, and hormonal steroids represent the ultimate biologically active products of cholesterol metabolism in vertebrates. However, intermediates in their formation, including oxysterols and cholestenoic acids, also possess known, e.g., as ligands to nuclear and G-protein-coupled receptors, and unknown regulatory activities. The potential diversity of molecules originating from the cholesterol structure is very broad and their abundance in biological materials ranges over several orders of magnitude. Here we describe the application of enzyme-assisted derivatization for sterol analysis (EADSA) in combination with liquid chromatography-electrospray ionization-mass spectrometry to define the oxysterol and cholestenoic acid metabolomes of human plasma. Quantitative profiling of adult plasma using EADSA leads to the detection of over 30 metabolites derived from cholesterol, some of which are ligands to the nuclear receptors LXR, FXR, and pregnane X receptor or the G-protein-coupled receptor Epstein-Barr virus-induced gene 2. The potential of the EADSA technique in screening for inborn errors of cholesterol metabolism and biosynthesis is demonstrated by the unique plasma profile of patients suffering from cerebrotendinous xanthomatosis. The analytical methods described are easily adapted to the analysis of other biological fluids, including cerebrospinal fluid, and also tissues, e.g., brain, in which nuclear and G-protein-coupled receptors may have important regulatory roles.
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Affiliation(s)
- William J Griffiths
- Institute of Mass Spectrometry, College of Medicine, Swansea University, Swansea SA2 8PP, UK.
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18
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A comprehensive machine-readable view of the mammalian cholesterol biosynthesis pathway. Biochem Pharmacol 2013; 86:56-66. [PMID: 23583456 PMCID: PMC3912678 DOI: 10.1016/j.bcp.2013.03.021] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 03/22/2013] [Accepted: 03/26/2013] [Indexed: 01/17/2023]
Abstract
Cholesterol biosynthesis serves as a central metabolic hub for numerous biological processes in health and disease. A detailed, integrative single-view description of how the cholesterol pathway is structured and how it interacts with other pathway systems is lacking in the existing literature. Here we provide a systematic review of the existing literature and present a detailed pathway diagram that describes the cholesterol biosynthesis pathway (the mevalonate, the Kandutch-Russell and the Bloch pathway) and shunt pathway that leads to 24(S),25-epoxycholesterol synthesis. The diagram has been produced using the Systems Biology Graphical Notation (SBGN) and is available in the SBGN-ML format, a human readable and machine semantically parsable open community file format.
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19
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Meljon A, Watson GL, Wang Y, Shackleton CHL, Griffiths WJ. Analysis by liquid chromatography-mass spectrometry of sterols and oxysterols in brain of the newborn Dhcr7(Δ3-5/T93M) mouse: a model of Smith-Lemli-Opitz syndrome. Biochem Pharmacol 2013; 86:43-55. [PMID: 23500538 DOI: 10.1016/j.bcp.2013.03.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2013] [Revised: 02/28/2013] [Accepted: 03/01/2013] [Indexed: 10/27/2022]
Abstract
In this study the sterol and oxysterol profile of newborn brain from the Dhcr7(Δ3-5/T93M) mouse model of Smith-Lemli-Opitz syndrome (SLOS) has been investigated. This is a viable mouse model which is compound heterozygous containing one null allele and one T93M mutation on Dhcr7. We find the SLOS mouse has reduced levels of cholesterol and desmosterol and increased levels of 7- and 8-dehydrocholesterol and of 7- and 8-dehydrodesmosterol in brain compared to the wild type. The profile of enzymatically formed oxysterols in the SLOS mouse resembles that in the wild type but the level of 24S-hydroxycholesterol, the dominating cholesterol metabolite, is reduced in a similar proportion to that of cholesterol. A number of oxysterols abundant in the SLOS mouse are probably derived from 7-dehydrocholesterol, however, the mechanism of their formation is unclear.
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Affiliation(s)
- Anna Meljon
- Institute of Mass Spectrometry, College of Medicine, Swansea University, Singleton Park, Swansea SA2 8PP, UK
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20
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Lavrynenko O, Nedielkov R, Möller HM, Shevchenko A. Girard derivatization for LC-MS/MS profiling of endogenous ecdysteroids in Drosophila. J Lipid Res 2013; 54:2265-2272. [PMID: 23843360 DOI: 10.1194/jlr.d035949] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Ecdysteroids are potent developmental regulators that control molting, reproduction, and stress response in arthropods. In developing larvae, picogram quantities of individual ecdysteroids and their conjugated forms are present along with milligrams of structural and energy storage lipids. To enhance the specificity and sensitivity of ecdysteroid detection, we targeted the 6-ketone group, which is common to all ecdysteroids, with Girard reagents. Unlike other ketosteroids, during the reaction, Girard hydrazones of ecdysteroids eliminated the C14-hydroxyl group, creating an additional C14-C15 double bond. Dehydrated hydrazones of endogenous ecdysteroids were detected by LC-MS/MS in the multiple reaction monitoring (MRM) mode using two mass transitions: one relied upon neutral loss of a quaternary amine from the Girard T moiety; another complementary transition followed neutral loss of the hydrocarbon chain upon C20-C27 cleavage. We further demonstrated that a combination of Girard derivatization and LC-MS/MS enabled unequivocal detection of three major endogenous hormones at the picogram level in an extract from a single Drosophila pupa.
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Affiliation(s)
- Oksana Lavrynenko
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany; and
| | - Ruslan Nedielkov
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Heiko M Möller
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Andrej Shevchenko
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany; and.
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21
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Methods for oxysterol analysis: past, present and future. Biochem Pharmacol 2013; 86:3-14. [PMID: 23395696 DOI: 10.1016/j.bcp.2013.01.027] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 01/28/2013] [Indexed: 12/20/2022]
Abstract
Oxysterols are oxidised forms of cholesterol or its precursors. In this article we will concentrate specifically on those formed in mammalian systems. Oxidation may be catalysed by endogenous enzymes or through reactive oxygen species forming a myriad of potential products. A number of these products are biologically active, and oxysterols may have roles in cholesterol homeostasis, neurogenesis, protein prenylation and in the immune system. Oxysterols are also implicated in aetiology of disease states including atherosclerosis, neurodegenerative and inflammatory diseases. Reports indicating the levels of oxysterols in plasma, cerebrospinal fluid and various tissues are in many cases unrealistic owing to a lack of attention to the possibility of autoxidation, a process by which oxysterols are formed from cholesterol by oxygen in air. This article comprises a critical assessment of the technical difficulties of oxysterol analysis, highlights methodologies utilising best practise and discusses newer procedures.
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22
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Brain endogenous liver X receptor ligands selectively promote midbrain neurogenesis. Nat Chem Biol 2012; 9:126-33. [PMID: 23292650 DOI: 10.1038/nchembio.1156] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Accepted: 11/21/2012] [Indexed: 01/05/2023]
Abstract
Liver X receptors (Lxrα and Lxrβ) are ligand-dependent nuclear receptors critical for ventral midbrain neurogenesis in vivo. However, no endogenous midbrain Lxr ligand has so far been identified. Here we used LC/MS and functional assays to identify cholic acid as a new Lxr ligand. Moreover, 24(S),25-epoxycholesterol (24,25-EC) was found to be the most potent and abundant Lxr ligand in the developing mouse midbrain. Both Lxr ligands promoted neural development in an Lxr-dependent manner in zebrafish in vivo. Notably, each ligand selectively regulated the development of distinct midbrain neuronal populations. Whereas cholic acid increased survival and neurogenesis of Brn3a-positive red nucleus neurons, 24,25-EC promoted dopaminergic neurogenesis. These results identify an entirely new class of highly selective and cell type-specific regulators of neurogenesis and neuronal survival. Moreover, 24,25-EC promoted dopaminergic differentiation of embryonic stem cells, suggesting that Lxr ligands may thus contribute to the development of cell replacement and regenerative therapies for Parkinson's disease.
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23
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Meljon A, Theofilopoulos S, Shackleton CHL, Watson GL, Javitt NB, Knölker HJ, Saini R, Arenas E, Wang Y, Griffiths WJ. Analysis of bioactive oxysterols in newborn mouse brain by LC/MS. J Lipid Res 2012; 53:2469-83. [PMID: 22891291 DOI: 10.1194/jlr.d028233] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Unesterified cholesterol is a major component of plasma membranes. In the brain of the adult, it is mostly found in myelin sheaths, where it plays a major architectural role. In the newborn mouse, little myelination of neurons has occurred, and much of this sterol comprises a metabolically active pool. In the current study, we have accessed this metabolically active pool and, using LC/MS, have identified cholesterol precursors and metabolites. Although desmosterol and 24S-hydroxycholesterol represent the major precursor and metabolite, respectively, other steroids, including the oxysterols 22-oxocholesterol, 22R-hydroxycholesterol, 20R,22R-dihydroxycholesterol, and the C(21)-neurosteroid progesterone, were identified. 24S,25-epoxycholesterol formed in parallel to cholesterol was also found to be a major sterol in newborn brain. Like 24S- and 22R-hydroxycholesterols, and also desmosterol, 24S,25-epoxycholesterol is a ligand to the liver X receptors, which are expressed in brain. The desmosterol metabolites (24Z),26-, (24E),26-, and 7α-hydroxydesmosterol were identified in brain for the first time.
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Affiliation(s)
- Anna Meljon
- Institute of Mass Spectrometry, College of Medicine, Swansea, UK
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24
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Fakheri RJ, Javitt NB. 27-Hydroxycholesterol, does it exist? On the nomenclature and stereochemistry of 26-hydroxylated sterols. Steroids 2012; 77:575-7. [PMID: 22366074 DOI: 10.1016/j.steroids.2012.02.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 02/05/2012] [Accepted: 02/06/2012] [Indexed: 11/15/2022]
Abstract
Significant ambiguity exists in the scientific community with regard to the nomenclature of 26-hydroxylated oxysterols. Oxysterols constitute an important class of compounds that have biological roles in the regulation of cholesterol synthesis and as endogenous selective estrogen receptor modulators (SERMs). The ambiguity is attributable to deviations from clearly stated IUPAC rules and is likely to increase as more biologically active oxysterols are identified. This review provides a uniform approach to the naming of 26-hydroxylated sterols for those of current interest and for those on the horizon such as oxysterols of lanosterol that retain the unsaturation at C-24 and C-25 such as (E)-26-hydroxylanosterol. Using this molecule as a starting point, this review hopes to establish a common language to keep all investigators on the same page.
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25
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Karu K, Turton J, Wang Y, Griffiths WJ. Nano-liquid chromatography-tandem mass spectrometry analysis of oxysterols in brain: monitoring of cholesterol autoxidation. Chem Phys Lipids 2011; 164:411-24. [PMID: 21575613 DOI: 10.1016/j.chemphyslip.2011.04.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2011] [Revised: 04/25/2011] [Accepted: 04/28/2011] [Indexed: 02/03/2023]
Abstract
Oxysterols are present in mammalian brain at ng/g-μg/g levels while cholesterol is present at the mg/g level. This makes oxysterol analysis of brain challenging. In an effort to meet this challenge we have developed, and validated, an isolation method based on solid phase extraction and an analytical protocol involving oxidation/derivatisation (i.e., charge-tagging) followed by nano-flow liquid chromatography (nano-LC) combined with tandem mass spectrometry utilising multi-stage fragmentation (MS(n)). The oxidation/derivatisation method employed improves detection limits by two orders of magnitude, while nano-LC-MS(n) provides separation of isomers and allows oxysterol quantification. Using this method 13 different oxysterols have been identified in rat brain including 24S-hydroxycholesterol, 24S,25-epoxycholesterol and 7α,26-dihydroxycholest-4-en-3-one. The level of 24S-hydroxycholesterol in rat brain was determined to be 20.3±3.4 μg/g and quantitative estimates were made for the other oxysterols identified. The presence of a large excess of cholesterol over oxysterol in brain raises the problem of autoxidation during sterol isolation and sample preparation. Thus, in parallel to identification studies, the degree of cholesterol autoxidation occurring during sterol isolation and analysis has been evaluated with the aid of [(2)H(7)]-labelled cholesterol and cholesterol autoxidation products identified.
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Affiliation(s)
- Kersti Karu
- The School of Pharmacy, University of London, London, UK
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26
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Griffiths WJ, Wang Y. Analysis of oxysterol metabolomes. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1811:784-99. [PMID: 21718802 DOI: 10.1016/j.bbalip.2011.05.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 05/19/2011] [Accepted: 05/23/2011] [Indexed: 10/18/2022]
Abstract
Oxysterols are oxygenated forms of cholesterol. This definition can, however, be expanded to include oxygenated derivatives of plant sterols and also of cholesterol precursors. Oxysterols are formed in the first steps of cholesterol metabolism and also from cholesterol by reactive oxygen species. Oxysterols were once thought of as simple intermediates, or side-products, in the conversion of cholesterol to hormonal steroids and bile acids, however, they have subsequently been shown to be biologically active molecules in their own right. In this article we will discuss methods of oxysterol analysis including "classical" gas chromatography-mass spectrometry (GC-MS) methods and more recent liquid chromatography (LC)-MS methods. Our main focus, however, will be on analytical methods based on "charge-tagging" and LC-tandem mass spectrometry (MS/MS or MS(n)) which we have developed over the last decade in our laboratory. Examples will be given of oxysterol analysis in brain, cerebrospinal fluid (CSF) and blood. The advantages and disadvantages of the various methods of oxysterol analysis will be discussed.
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27
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Griffiths WJ, Ogundare M, Williams CM, Wang Y. On the future of "omics": lipidomics. J Inherit Metab Dis 2011; 34:583-92. [PMID: 21318352 DOI: 10.1007/s10545-010-9274-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 12/19/2010] [Accepted: 12/23/2010] [Indexed: 12/13/2022]
Abstract
Following in the wake of the genomic and proteomic revolutions new fields of "omics" research are emerging. The metabolome provides the natural complement to the genome and proteome, however, the extreme physicochemical diversity of the metabolome leads to a subdivision of metabolites into compounds soluble in aqueous solutions or those soluble in organic solvents. A complete molecular and quantitative investigation of the latter when isolated from tissue, fluid or cells constitutes lipidomics. Like proteomics, lipidomics is a subject which is both technology driven and technology driving, with the primary technologies being mass spectrometry, with or without on-line chromatography and computer-assisted data analysis. In this paper we will examine the underlying fundamentals of different lipidomic experimental approaches including the "shotgun" and "top-down" global approaches, and the more targeted liquid chromatography - or gas chromatography - mass spectrometry approaches. Application of these approaches to the identification of in-born errors of metabolism will be discussed.
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Affiliation(s)
- William J Griffiths
- Institute of Mass Spectrometry, School of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
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28
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Shui G, Cheong WF, Jappar IA, Hoi A, Xue Y, Fernandis AZ, Tan BKH, Wenk MR. Derivatization-independent cholesterol analysis in crude lipid extracts by liquid chromatography/mass spectrometry: applications to a rabbit model for atherosclerosis. J Chromatogr A 2011; 1218:4357-65. [PMID: 21621788 DOI: 10.1016/j.chroma.2011.05.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2010] [Revised: 02/22/2011] [Accepted: 05/08/2011] [Indexed: 10/18/2022]
Abstract
Direct measurement of various sterols in crude lipid extracts in a single experiment from limited biological samples is challenging. Current mass spectrometry (MS) based approaches usually require chemical derivatization before subjecting to MS analysis. Here, we present a derivatization-independent method for analyzing various sterols, including cholesterol and its congeners, using liquid chromatography and atmospheric pressure chemical ionization mass spectrometry. Based on the specific tandem mass spectrometry pattern of cholesterol, multiple reaction monitoring (MRM) transitions were used to quantify free cholesterol and its fatty acyl esters. Several cholesterol oxidation products could also be measured using the upfront liquid chromatography separation and specific MRM transitions. The method was validated alongside established enzymatic assays in measuring total cholesterol. As a proof of concept, we analyzed plasma sterols in rabbits administrated with a high cholesterol diet (HCD) which is a classical atherosclerotic model. Free cholesterol, cholesterol esters, 7-hydroxycholesterol, and 7-ketocholesterol were elevated in plasma of rabbits on HCD. This method could also serve as an excellent tool for quantitative analysis of other sterols such as ergosterol and sitosterol in other organisms beside mammalian. In Saccharomyces cerevisiae, our results indicated dramatic increases of the ratio of ergosterol esters to free ergosterol in both yeh2Δ and tgl1Δ cells, which are consistent with the function of the respective enzymes.
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Affiliation(s)
- Guanghou Shui
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
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29
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Korade Z, Xu L, Shelton R, Porter NA. Biological activities of 7-dehydrocholesterol-derived oxysterols: implications for Smith-Lemli-Opitz syndrome. J Lipid Res 2010; 51:3259-69. [PMID: 20702862 DOI: 10.1194/jlr.m009365] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Smith-Lemli-Opitz syndrome (SLOS) is a metabolic and developmental disorder caused by mutations in the gene encoding the enzyme 7-dehydrocholesterol reductase (Dhcr7). This reductase catalyzes the last step in cholesterol biosynthesis, and levels of 7-dehydrocholesterol (7-DHC), the substrate for this enzyme, are elevated in SLOS patients as a result of this defect. Our group has previously shown that 7-DHC is extremely prone to free radical autoxidation, and we identified about a dozen different oxysterols formed from oxidation of 7-DHC. We report here that 7-DHC-derived oxysterols reduce cell viability in a dose- and time-dependent manner, some of the compounds showing activity at sub-micromolar concentrations. The reduction of cell survival is caused by a combination of reduced proliferation and induced differentiation of the Neuro2a cells. The complex 7-DHC oxysterol mixture added to control Neuro2a cells also triggers the gene expression changes that were previously identified in Dhcr7-deficient Neuro2a cells. Based on the identification of overlapping gene expression changes in Dhcr7-deficient and 7-DHC oxysterol-treated Neuro2a cells, we hypothesize that some of the pathophysiological findings in the mouse SLOS model and SLOS patients might be due to accumulated 7-DHC oxysterols.
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Affiliation(s)
- Zeljka Korade
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37235, USA
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30
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Abstract
Although lipids are biomolecules with seemingly simple chemical structures, the molecular composition of the cellular lipidome is complex and, currently, poorly understood. The exact mechanisms of how compositional complexity affects cell homeostasis and its regulation also remain unclear. This emerging field is developing sensitive mass spectrometry technologies for the quantitative characterization of the lipidome. Here, we argue that lipidomics will become an essential tool kit in cell and developmental biology, molecular medicine and nutrition.
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31
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Analytical strategies for characterization of bile acid and oxysterol metabolomes. Biochem Biophys Res Commun 2010; 396:80-4. [PMID: 20494115 DOI: 10.1016/j.bbrc.2010.02.149] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2010] [Accepted: 02/23/2010] [Indexed: 01/26/2023]
Abstract
Cholesterol is the precursor of many compounds with functions in the physiology and metabolism of the organism. Methods for the multicomponent analysis of these compounds and their metabolites (metabolomics) are needed to improve our understanding of their roles in different species, organs, cells and metabolic situations and to clarify structure/activity relationships. This review discusses methods based on combinations of ion exchange and reversed-phase separations for sample preparation with derivatization and "charge-tagging" for chromatography-mass spectrometry in qualitative and quantitative characterizations of oxysterol, bile alcohol, bile acid, and steroid hormone metabolomes. Advantages, disadvantages and potential improvements for high-throughput applications are briefly discussed.
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32
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Ogundare M, Theofilopoulos S, Lockhart A, Hall LJ, Arenas E, Sjövall J, Brenton AG, Wang Y, Griffiths WJ. Cerebrospinal fluid steroidomics: are bioactive bile acids present in brain? J Biol Chem 2009; 285:4666-79. [PMID: 19996111 DOI: 10.1074/jbc.m109.086678] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In this study we have profiled the free sterol content of cerebrospinal fluid by a combination of charge tagging and liquid chromatography-tandem mass spectrometry. Surprisingly, the most abundant cholesterol metabolites were found to be C(27) and C(24) intermediates of the bile acid biosynthetic pathways with structures corresponding to 7alpha-hydroxy-3-oxocholest-4-en-26-oic acid (7.170 +/- 2.826 ng/ml, mean +/- S.D., six subjects), 3beta-hydroxycholest-5-en-26-oic acid (0.416 +/- 0.193 ng/ml), 7alpha,x-dihydroxy-3-oxocholest-4-en-26-oic acid (1.330 +/- 0.543 ng/ml), and 7alpha-hydroxy-3-oxochol-4-en-24-oic acid (0.172 +/- 0.085 ng/ml), and the C(26) sterol 7alpha-hydroxy-26-norcholest-4-ene-3,x-dione (0.204 +/- 0.083 ng/ml), where x is an oxygen atom either on the CD rings or more likely on the C-17 side chain. The ability of intermediates of the bile acid biosynthetic pathways to activate the liver X receptors (LXRs) and the farnesoid X receptor was also evaluated. The acidic cholesterol metabolites 3beta-hydroxycholest-5-en-26-oic acid and 3beta,7alpha-dihydroxycholest-5-en-26-oic acid were found to activate LXR in a luciferase assay, but the major metabolite identified in this study, i.e. 7alpha-hydroxy-3-oxocholest-4-en-26-oic acid, was not an LXR ligand. 7Alpha-hydroxy-3-oxocholest-4-en-26-oic acid is formed from 3beta,7alpha-dihydroxycholest-5-en-26-oic acid in a reaction catalyzed by 3beta-hydroxy-Delta(5)-C(27)-steroid dehydrogenase (HSD3B7), which may thus represent a deactivation pathway of LXR ligands in brain. Significantly, LXR activation has been found to reduce the symptoms of Alzheimer disease (Fan, J., Donkin, J., and Wellington C. (2009) Biofactors 35, 239-248); thus, cholesterol metabolites may play an important role in the etiology of Alzheimer disease.
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Affiliation(s)
- Michael Ogundare
- Institute of Mass Spectrometry, School of Medicine, Grove Building, Swansea University, Singleton Park, Swansea SA2 8PP, United Kingdom
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33
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Griffiths WJ, Wang Y. Analysis of neurosterols by GC-MS and LC-MS/MS. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:2778-805. [PMID: 19560986 DOI: 10.1016/j.jchromb.2009.05.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Revised: 05/07/2009] [Accepted: 05/09/2009] [Indexed: 10/20/2022]
Abstract
The term neurosteroid was coined by Baulieu and colleagues in Paris towards the end of the last century to describe steroids which are synthesised in the central or peripheral nervous system [E.E. Baulieu, Psychoneuroendocrinology 23 (1998) 963-87]. This definition was restricted to side-chain "shortened" steroids with 21 carbon atoms or less, and excluded sterols and their carboxylic acids with an intact side-chain. By analogy, we now use the term neurosterol to describe C(27) sterols synthesised in the nervous system. In this review we discuss the biological importance of neurosterols, and how they are extracted, isolated, and analysed by GC-MS and LC-MS/MS, from brain and relevant body fluids. We present applications of methodology employed for analysis of specific sterols and comment on the relative merits of the methods employed. Finally, the importance of future in-depth "sterolomic" investigations of brain is highlighted.
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Affiliation(s)
- William J Griffiths
- Institute of Mass Spectrometry, School of Medicine, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
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