Defective cholesterol metabolism in amyotrophic lateral sclerosis

As neurons die, cholesterol is released in the central nervous system (CNS); hence, this sterol and its metabolites may represent a biomarker of neurodegeneration, including in amyotrophic lateral sclerosis (ALS), in which altered cholesterol levels have been linked to prognosis. More than 40 different sterols were quantified in serum and cerebrospinal fluid (CSF) from ALS patients and healthy controls. In CSF, the concentration of cholesterol was found to be elevated in ALS samples. When CSF metabolite levels were normalized to cholesterol, the cholesterol metabolite 3β,7α-dihydroxycholest-5-en-26-oic acid, along with its precursor 3β-hydroxycholest-5-en-26-oic acid and product 7α-hydroxy-3-oxocholest-4-en-26-oic acid, were reduced in concentration, whereas metabolites known to be imported from the circulation into the CNS were not found to differ in concentration between groups. Analysis of serum revealed that (25R)26-hydroxycholesterol, the immediate precursor of 3β-hydroxycholest-5-en-26-oic acid, was reduced in concentration in ALS patients compared with controls. We conclude that the acidic branch of bile acid biosynthesis, known to be operative in-part in the brain, is defective in ALS, leading to a failure of the CNS to remove excess cholesterol, which may be toxic to neuronal cells, compounded by a reduction in neuroprotective 3β,7α-dihydroxycholest-5-en-26-oic acid. As neurons die, cholesterol is released in the central nervous system (CNS); hence, this sterol and its metabolites may represent a biomarker of neurodegeneration, including in amyotrophic lateral sclerosis (ALS), in which altered cholesterol levels have been linked to prognosis. More than 40 different sterols were quantified in serum and cerebrospinal fluid (CSF) from ALS patients and healthy controls. In CSF, the concentration of cholesterol was found to be elevated in ALS samples. When CSF metabolite levels were normalized to cholesterol, the cholesterol metabolite 3β,7α-dihydroxycholest-5-en-26-oic acid, along with its precursor 3β-hydroxycholest-5-en-26-oic acid and product 7α-hydroxy-3-oxocholest-4-en-26-oic acid, were reduced in concentration, whereas metabolites known to be imported from the circulation into the CNS were not found to differ in concentration between groups. Analysis of serum revealed that (25R)26-hydroxycholesterol, the immediate precursor of 3β-hydroxycholest-5-en-26-oic acid, was reduced in concentration in ALS patients compared with controls. We conclude that the acidic branch of bile acid biosynthesis, known to be operative in-part in the brain, is defective in ALS, leading to a failure of the CNS to remove excess cholesterol, which may be toxic to neuronal cells, compounded by a reduction in neuroprotective 3β,7α-dihydroxycholest-5-en-26-oic acid. Amyotrophic lateral sclerosis (ALS) is a heterogeneous, progressive, and fatal neurodegenerative disease characterized by variable loss of upper and lower motor neurons (1Kiernan M.C. Vucic S. Cheah B.C. Turner M.R. Eisen A. Hardiman O. Burrell J.R. Zoing M.C. Amyotrophic lateral sclerosis.Lancet. 2011; 377: 942-955Abstract Full Text Full Text PDF PubMed Scopus (1797) Google Scholar). Biomarkers that are sensitive to the progression of disease have the potential to shorten therapeutic trials and provide new drug targets. Study of the metabolome offers the potential to identify disease-specific patterns for ALS, possibly providing such biomarkers and new insights into the deranged biochemical pathways associated with ALS. Metabolomic studies in blood and cerebrospinal fluid (CSF) have been performed utilizing proton nuclear magnetic resonance spectrometry (2Gray E. Larkin J.R. Claridge T.D. Talbot K. Sibson N.R. Turner M.R. The longitudinal cerebrospinal fluid metabolomic profile of amyotrophic lateral sclerosis.Amyotroph. Lateral Scler. Frontotemporal Degener. 2015; 16: 456-463Crossref PubMed Scopus (34) Google Scholar, 3Blasco H. Corcia P. Moreau C. Veau S. Fournier C. Vourc'h P. Emond P. Gordon P. Pradat P.F. Praline J. et al.1H-NMR-based metabolomic profiling of CSF in early amyotrophic lateral sclerosis.PLoS One. 2010; 5: e13223Crossref PubMed Scopus (95) Google Scholar, 4Kumar A. Bala L. Kalita J. Misra U.K. Singh R.L. Khetrapal C.L. Babu G.N. Metabolomic analysis of serum by (1) H NMR spectroscopy in amyotrophic lateral sclerosis.Clin. Chim. Acta. 2010; 411: 563-567Crossref PubMed Scopus (68) Google Scholar), GC/MS, and LC/MS (5Wuolikainen A. Moritz T. Marklund S.L. Antti H. Andersen P.M. Disease-related changes in the cerebrospinal fluid metabolome in amyotrophic lateral sclerosis detected by GC/TOFMS.PLoS One. 2011; 6: e17947Crossref PubMed Scopus (67) Google Scholar, 6Blasco H. Corcia P. Pradat P.F. Bocca C. Gordon P.H. Veyrat-Durebex C. Mavel S. Nadal-Desbarats L. Moreau C. Devos D. et al.Metabolomics in cerebrospinal fluid of patients with amyotrophic lateral sclerosis: an untargeted approach via high-resolution mass spectrometry.J. Proteome Res. 2013; 12: 3746-3754Crossref PubMed Scopus (67) Google Scholar). Significant differences between patients and controls have been observed, consistent with a range of pathogenic mechanisms that have been described in ALS, including mitochondrial dysfunction, oxidative stress, excitotoxicity, neuroinflammation, and hypermetabolism (7Turner M.R. Bowser R. Bruijn L. Dupuis L. Ludolph A. McGrath M. Manfredi G. Maragakis N. Miller R.G. Pullman S.L. et al.Mechanisms, models and biomarkers in amyotrophic lateral sclerosis.Amyotroph. Lateral Scler. Frontotemporal Degener. 2013; 14: 19-32Crossref PubMed Scopus (121) Google Scholar). Lipids, distinct from other components of the metabolome (8Sud M. Fahy E. Cotter D. Azam K. Vadivelu I. Burant C. Edison A. Fiehn O. Higashi R. Nair K.S. et al.Metabolomics Workbench: An international repository for metabolomics data and metadata, metabolite standards, protocols, tutorials and training, and analysis tools.Nucleic Acids Res. 2016; 44: D463-D470Crossref PubMed Scopus (344) Google Scholar), are nonpolar or amphipathic in nature and require separate analysis from more water-soluble metabolites. Cholesterol, both the nonesterified molecule and its esters with fatty acids, represents a major component of the total lipid content of cells in vertebrates. On a number of fronts, cholesterol and its metabolites represent potential biomarkers for ALS. High plasma levels of cholesterol have been suggested to be neuroprotective for ALS and to be associated with an increased survival time (9Dupuis L. Corcia P. Fergani A. Gonzalez De Aguilar J.L. Bonnefont-Rousselot D. Bittar R. Seilhean D. Hauw J.J. Lacomblez L. Loeffler J.P. et al.Dyslipidemia is a protective factor in amyotrophic lateral sclerosis.Neurology. 2008; 70: 1004-1009Crossref PubMed Scopus (392) Google Scholar, 10Sutedja N.A. van der Schouw Y.T. Fischer K. Sizoo E.M. Huisman M.H. Veldink J.H. Van den Berg L.H. Beneficial vascular risk profile is associated with amyotrophic lateral sclerosis.J. Neurol. Neurosurg. Psychiatry. 2011; 82: 638-642Crossref PubMed Scopus (107) Google Scholar, 11Dorst J. Kuhnlein P. Hendrich C. Kassubek J. Sperfeld A.D. Ludolph A.C. Patients with elevated triglyceride and cholesterol serum levels have a prolonged survival in amyotrophic lateral sclerosis.J. Neurol. 2011; 258: 613-617Crossref PubMed Scopus (180) Google Scholar), but other data suggest that accumulation of cholesterol esters and ceramides mediate oxidative stress in motor neurons in ALS (12Cutler R.G. Pedersen W.A. Camandola S. Rothstein J.D. Mattson M.P. Evidence that accumulation of ceramides and cholesterol esters mediates oxidative stress-induced death of motor neurons in amyotrophic lateral sclerosis.Ann. Neurol. 2002; 52: 448-457Crossref PubMed Scopus (214) Google Scholar), while the gene cytochrome P450 27A1 (CYP27A1), encoding cholesterol (25R)26-hydroxylase (also known as sterol 27-hydroxylase), the first enzyme in the extrahepatic part of the bile acid biosynthesis pathway, was recently identified as a susceptibility gene for sporadic ALS (13Diekstra F.P. Saris C.G. van Rheenen W. Franke L. Jansen R.C. van Es M.A. van Vught P.W. Blauw H.M. Groen E.J. Horvath S. et al.Mapping of gene expression reveals CYP27A1 as a susceptibility gene for sporadic ALS.PLoS One. 2012; 7: e35333Crossref PubMed Scopus (43) Google Scholar). In addition, statins, the cholesterol-lowering drugs that inhibit HMG-CoA reductase, have been suggested to accelerate functional decline in ALS patients (14Zheng Z. Sheng L. Shang H. Statins and amyotrophic lateral sclerosis: a systematic review and meta-analysis.Amyotroph. Lateral Scler. Frontotemporal Degener. 2013; 14: 241-245Crossref PubMed Scopus (28) Google Scholar). ALS is a neurodegenerative disease and as neurons die, cholesterol is released from cells. Cholesterol and its metabolites in the CNS are predominantly in a nonesterified form (15Dietschy J.M. Turley S.D. Thematic review series: brain Lipids. Cholesterol metabolism in the central nervous system during early development and in the mature animal.J. Lipid Res. 2004; 45: 1375-1397Abstract Full Text Full Text PDF PubMed Scopus (773) Google Scholar), and it the nonesterified molecules that are responsible for regulating cholesterol homeostasis (16Zhang Y. Lee K.M. Kinch L.N. Clark L. Grishin N.V. Rosenbaum D.M. Brown M.S. Goldstein J.L. Radhakrishnan A. Direct demonstration that Loop1 of Scap binds to Loop7: a CRUCIAL EVENT IN CHOLESTEROL HOMEOSTASIS.J. Biol. Chem. 2016; 291: 12888-12896Abstract Full Text Full Text PDF PubMed Scopus (13) Google Scholar, 17Radhakrishnan A. Ikeda Y. Kwon H.J. Brown M.S. Goldstein J.L. Sterol-regulated transport of SREBPs from endoplasmic reticulum to Golgi: oxysterols block transport by binding to Insig.Proc. Natl. Acad. Sci. USA. 2007; 104: 6511-6518Crossref PubMed Scopus (433) Google Scholar) and are the ligands to nuclear receptors (18Evans R.M. Mangelsdorf D.J. Nuclear Receptors, RXR, and the Big Bang.Cell. 2014; 157: 255-266Abstract Full Text Full Text PDF PubMed Scopus (753) Google Scholar, 19Gustafsson J.A. Control of gene expression by novel metabolic intermediates.J. Steroid Biochem. Mol. Biol. 2015; 153: 102-104Crossref PubMed Scopus (1) Google Scholar) and ligands to G-protein-coupled receptors (20Hannedouche S. Zhang J. Yi T. Shen W. Nguyen D. Pereira J.P. Guerini D. Baumgarten B.U. Roggo S. Wen B. et al.Oxysterols direct immune cell migration via EBI2.Nature. 2011; 475: 524-527Crossref PubMed Scopus (314) Google Scholar, 21Liu C. Yang X.V. Wu J. Kuei C. Mani N.S. Zhang L. Yu J. Sutton S.W. Qin N. Banie H. et al.Oxysterols direct B-cell migration through EBI2.Nature. 2011; 475: 519-523Crossref PubMed Scopus (251) Google Scholar). We aimed to characterize and quantify nonesterified cholesterol and the widest range of nonesterified metabolites in CSF and serum from ALS patients compared with a group of healthy controls (see Table 1for molecules analyzed). An LC/MS approach was adopted to exploit charge-tagging to ensure maximum sensitivity and to gain structural information allowing identification of unexpected sterols (supplemental Fig. S1); a hydrolysis step was not included in the sample preparation protocol (22Griffiths W.J. Crick P.J. Wang Y. Ogundare M. Tuschl K. Wang Y. for of ligands in Biol. 2013; PubMed Scopus Google Scholar, P.J. T. J. I. C. L. L. et for sterol and Chem. 2015; PubMed Scopus Google and in serum and of to or product of not and to to not and to to to to of and its product of and its product not and not and to to to not of The to product of not and The to The to of and its product of and its product to in a new not was from patients with ALS patients with lateral sclerosis and CSF was from ALS patients and controls and CSF were from ALS and patients and healthy and as part of The Study for Biomarkers in and the of ALS and to and the was by the B. CSF for development were from a performed of serum was to a of of of of of of of and of sterols from with in an of was to the a of the was for separate cholesterol from the more oxysterols and acids, the sample in of was a with of and of The through the was a of by the by a The was with a of to in which and was by with a of cholesterol and sterols of was with of a in of was lipid more than cholesterol was into and and to that a hydrolysis step was not included in the sample preparation and by cholesterol from its metabolites in the first step of sample with is was in of sample was of was of cholesterol from in The was for which the was with of were to but in the of cholesterol of acid was to and and of P.J. T. J. I. C. L. L. et for sterol and Chem. 2015; PubMed Scopus Google Scholar), was to of was to to for LC/MS (supplemental Fig. the was to in the remove excess a was with of of and of the were The sample was with of and the was to the of was to the and the of was with of to of was to the by a of the with of The of was with of to a of the to the the by which and were by the whereas to of was to the and acids, and more nonpolar sterols were from the with and of and in the first from the Cholesterol and sterols of of and acid analysis by an of from and was in cholesterol analysis of from and were In both the in was with to a concentration of the of the during Analysis was performed a with an and a system as described (22Griffiths W.J. Crick P.J. Wang Y. Ogundare M. Tuschl K. Wang Y. for of ligands in Biol. 2013; PubMed Scopus Google Scholar, P.J. T. J. I. C. L. L. et for sterol and Chem. 2015; PubMed Scopus Google Scholar). to were high-resolution maximum in the in with to in the was performed by or by structural of CSF was to of of of of of of and of with in an of was and the was for by for The CSF sample in of was a as in the serum the was with a of of to in which and The of the sample preparation including was to that for with the that the from were and in to sample the An was for were performed the in the are for sterol analysis (22Griffiths W.J. Crick P.J. Wang Y. Ogundare M. Tuschl K. Wang Y. for of ligands in Biol. 2013; PubMed Scopus Google Scholar) in with LC/MS with serum from patients with ALS and patients with the upper motor of ALS, were compared with the of nonesterified cholesterol, of its and metabolites were (see Table for and and Table for that a hydrolysis step was not are for nonesterified We to in the sample and included both in the was in the of cholesterol or its or between ALS, or samples. the concentration of as the of and its which are The is an product of W.J. J. Crick P.J. Ogundare M. Tuschl K. A. et and oxysterols in plasma from Steroid Biochem. Mol. Biol. 2016; of 2016; Scholar). was in the concentration of the metabolite in serum of the ALS patients compared with controls The first of cholesterol metabolism to known as pathway, in to by metabolism to and Fig. was elevated in ALS serum and are the first of the of bile acid biosynthesis The and of bile acid Biochem. PubMed Scopus Google a in concentration between ALS, or and or and be via of cholesterol, and metabolites have been suggested as of stress L. S. S. M. W. L. of oxysterols and in plasma and as of stress Biochem. PubMed Scopus Google of cholesterol metabolism by the and in sterols concentration in CSF and serum are by and The of to the of the the are are as bile or enzyme sterol were performed the the first of the extrahepatic part of the acidic of bile acid biosynthesis, was in ALS and serum compared with controls as was 3β-hydroxycholest-5-en-26-oic acid in ALS serum CYP27A1 is the enzyme responsible for of cholesterol and to the acid. that the systematic E. S. Brown R.C. Y. W. et system for Lipid Res. Full Text Full Text PDF PubMed Scopus Google Scholar), of the of the cholesterol in it On the and of 2012; PubMed Scopus Google Scholar). is The for in the of the of its is of in the circulation are to cholesterol, with cholesterol levels associated with levels of A. S. B. N. J. K. M. I. Patients with may have increased levels of and J. PubMed Scopus (34) Google Scholar). We to for sample the of and other metabolites to cholesterol to the differences were When normalized to cholesterol (supplemental Table in concentration of was in ALS, as was a in the concentration of in an et A. J. A. P. Andersen P.M. I. Cholesterol, and homeostasis in ALS. Evidence the that elevated is a pathogenic One. 2014; PubMed Scopus (34) Google Scholar) found that in ALS patients was In suggest reduced or of cholesterol (25R)26-hydroxylase in ALS. As with levels of cholesterol, and were in CSF from ALS patients and controls The of both and cholesterol were found to be elevated in CSF from ALS patients Table ALS is a neurodegenerative cholesterol is released by neurons as die, it be by to and by CYP27A1 to of the acidic of bile acid biosynthesis and The and of bile acid Biochem. PubMed Scopus Google Scholar). normalized to cholesterol, concentration was found to be reduced in CSF, as were of the acidic of bile acid biosynthesis (supplemental Table of and which from the of the bile acid biosynthesis and the CSF from the not differ between ALS patients and controls be is not in the The and of bile acid Biochem. PubMed Scopus Google Scholar). The of was not lower in CSF from ALS patients compared with controls but its metabolites 3β,7α-dihydroxycholest-5-en-26-oic acid and 7α-hydroxy-3-oxocholest-4-en-26-oic acid were reduced in concentration in ALS CSF by CYP27A1 in the by the and of the group by in the endoplasmic metabolism to bile in the S. S. the of Lipid Res. Full Text Full Text PDF PubMed Scopus Google Scholar). metabolites found in CSF acid acid which is as the and the product acid the of the of the were or in CSF from ALS of and metabolites in and of and in CSF from ALS patients and healthy controls and are as described in the Fig. for other sterols be found in Table were performed the of acidic metabolites in and of and in CSF from ALS patients and healthy controls and are as described in the Fig. for other sterols be found in Table were performed the The major for cholesterol metabolism in the CNS is to via the enzyme D.M. R. T. Cholesterol an enzyme of cholesterol in the Biochem. PubMed Scopus Google Scholar, I. of 2007; PubMed Scopus Google Scholar), for of cholesterol metabolism in brain, and elevated levels of total have been found in CSF of patients with neurodegenerative disease T. B. J. I. of and Chem. 2004; PubMed Scopus Google Scholar, I. with 2013; PubMed Scopus Google Scholar). The total the of both and nonesterified In of total cholesterol or of total are sterols with fatty are and the total sterol is it is the nonesterified sterols that are the of to nonesterified sterol in plasma is S. O. E. of cholesterol in plasma by Biochem. PubMed Scopus Google Scholar). levels of total are in blood plasma of patients with as a of a reduced number of neurons L. A. D. L. M. J. C.G. I. levels of in patients with PubMed Scopus Google Scholar). In a et found total plasma levels to be increased in ALS but not in whereas total was reduced in ALS but not A. J. A. P. Andersen P.M. I. Cholesterol, and homeostasis in ALS. Evidence the that elevated is a pathogenic One. 2014; PubMed Scopus (34) Google Scholar). and and acids, are ligands to receptors the in brain, motor S. N. M. J.A. of to motor in Natl. Acad. Sci. USA. PubMed Scopus Google Scholar, H.J. C. K. P. M. J.A. a between and amyotrophic lateral Natl. Acad. Sci. USA. 2008; PubMed Scopus Google Scholar). is in of and cholesterol and increased cholesterol levels in and motor loss and disease P. A. L. G. S. S. E. P. T. et and biochemical changes during disease progression in a of Neurol. 2010; PubMed Scopus Google Scholar). In the a loss of may from reduced CNS levels of and acid leading to motor cholesterol the and be imported or the brain, and other cholesterol metabolites the I. with 2013; PubMed Scopus Google Scholar, G. T. D. M. N. Crick P. Wang Y. W. et of a cholesterol homeostasis in the Biol. Chem. 2014; Full Text Full Text PDF PubMed Scopus Google Scholar). et M. S. D. J. I. the of into the Lipid Res. Full Text Full Text PDF PubMed Scopus Google Scholar) have that is imported to the brain, whereas et S. M. L. M. I. J. W. et for of brain oxysterols the into Lipid Res. 2007; Full Text Full Text PDF PubMed Scopus Google Scholar) have that its acidic metabolite is from the brain to studies by et L. Crick P.J. C. L. J. M. Wang Y. W.J. Cholesterol metabolites from 2015; PubMed Scopus Google Scholar) have that a precursor of this acid, is from the brain to as is its In Ogundare et M. S. A. E. J. Wang Y. W.J. fluid are bile in Biol. Chem. 2010; Full Text Full Text PDF PubMed Scopus Google Scholar) have that of the acidic of bile acid biosynthesis are in the of the was the in concentration of nonesterified cholesterol in the CSF of ALS patients was associated with a in the concentration of oxysterols and acids, but not of cholesterol metabolites imported from the circulation and for increased cholesterol levels in CSF of ALS patients is that cholesterol is released from as neurons die, and metabolic pathways are and to remove this excess in ALS patients An is that is transport of sterols between neurons and in cholesterol metabolism in the CNS of ALS patients as a of is by studies the which not motor but increased cholesterol accumulation of cholesterol in and motor loss and disease P. A. L. G. S. S. E. P. T. et and biochemical changes during disease progression in a of Neurol. 2010; PubMed Scopus Google Scholar). motor loss is not but is known to the N. P. receptors as of metabolic and PubMed Scopus Google Scholar), and is an pathogenic factor in ALS M.C. Y. Sibson N. Turner M.R. and changes in amyotrophic lateral 2013; PubMed Scopus Google Scholar). In and were increased in that a in the CNS by levels of and development of P. A. L. G. S. S. E. P. T. et and biochemical changes during disease progression in a of Neurol. 2010; PubMed Scopus Google Scholar). the and the and found to be reduced in CSF from ALS are ligands S. W.J. Crick P.J. Yang S. A. Ogundare M. A. Tuschl K. et motor survival via 2014; PubMed Scopus Google Scholar). in ALS may be associated with a reduction in CNS ligands In been a neuroprotective motor neurons through the the other to be S. W.J. Crick P.J. Yang S. A. Ogundare M. A. Tuschl K. et motor survival via 2014; PubMed Scopus Google Scholar). for reduced levels of ligands in the CSF of ALS patients is as neurons in ALS, of the endoplasmic reticulum enzyme is to cholesterol to for its reduced concentration in the ligands found in the CSF, including and are from cholesterol in J. Y. M. J. of and in cells and J. PubMed Scopus (68) Google Scholar). The first enzyme in from cholesterol is mitochondrial CYP27A1 CYP27A1 been identified as a susceptibility gene for sporadic ALS (13Diekstra F.P. Saris C.G. van Rheenen W. Franke L. Jansen R.C. van Es M.A. van Vught P.W. Blauw H.M. Groen E.J. Horvath S. et al.Mapping of gene expression reveals CYP27A1 as a susceptibility gene for sporadic ALS.PLoS One. 2012; 7: e35333Crossref PubMed Scopus (43) Google Scholar). in CYP27A1 leading to a defective CYP27A1 enzyme are the of the neurodegenerative of bile acid 2011; PubMed Scopus Google Scholar). for a for oxysterols in from the by et cholesterol molecules to of and by the sterol cholesterol biosynthesis A. G. of 2014; PubMed Scopus Google Scholar). it been that inhibit cholesterol biosynthesis Y. S. J. W.J. The of cholesterol homeostasis in changes to the Proteome Res. 2008; 7: PubMed Scopus Google Scholar), reduced levels of in the as in ALS, in cholesterol biosynthesis and and In have identified elevated cholesterol in the CSF of ALS When normalized to cholesterol, of acidic metabolites are but cholesterol metabolites imported from the circulation are data to of the CYP27A1 enzyme leading to a failure of the CNS to remove excess cholesterol, which may be toxic to neuronal cells, compounded by a reduction in neuroprotective and other ligands The of the for for with amyotrophic lateral sclerosis cerebrospinal fluid cytochrome P450 lateral sclerosis 3β-hydroxycholest-5-en-26-oic acid 3β,7α-dihydroxycholest-5-en-26-oic acid acid 7α-hydroxy-3-oxocholest-4-en-26-oic acid

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