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Petrov AM. Oxysterols in Central and Peripheral Synaptic Communication. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1440:91-123. [PMID: 38036877 DOI: 10.1007/978-3-031-43883-7_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
Cholesterol is a key molecule for synaptic transmission, and both central and peripheral synapses are cholesterol rich. During intense neuronal activity, a substantial portion of synaptic cholesterol can be oxidized by either enzymatic or non-enzymatic pathways to form oxysterols, which in turn modulate the activities of neurotransmitter receptors (e.g., NMDA and adrenergic receptors), signaling molecules (nitric oxide synthases, protein kinase C, liver X receptors), and synaptic vesicle cycling involved in neurotransmitters release. 24-Hydroxycholesterol, produced by neurons in the brain, could directly affect neighboring synapses and change neurotransmission. 27-Hydroxycholesterol, which can cross the blood-brain barrier, can alter both synaptogenesis and synaptic plasticity. Increased generation of 25-hydroxycholesterol by activated microglia and macrophages could link inflammatory processes to learning and neuronal regulation. Amyloids and oxidative stress can lead to an increase in the levels of ring-oxidized sterols and some of these oxysterols (4-cholesten-3-one, 5α-cholestan-3-one, 7β-hydroxycholesterol, 7-ketocholesterol) have a high potency to disturb or modulate neurotransmission at both the presynaptic and postsynaptic levels. Overall, oxysterols could be used as "molecular prototypes" for therapeutic approaches. Analogs of 24-hydroxycholesterol (SGE-301, SGE-550, SAGE718) can be used for correction of NMDA receptor hypofunction-related states, whereas inhibitors of cholesterol 24-hydroxylase, cholestane-3β,5α,6β-triol, and cholest-4-en-3-one oxime (olesoxime) can be utilized as potential anti-epileptic drugs and (or) protectors from excitotoxicity.
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Affiliation(s)
- Alexey M Petrov
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", Kazan, RT, Russia.
- Kazan State Medial University, Kazan, RT, Russia.
- Kazan Federal University, Kazan, RT, Russia.
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Alavi MS, Karimi G, Ghanimi HA, Roohbakhsh A. The potential of CYP46A1 as a novel therapeutic target for neurological disorders: An updated review of mechanisms. Eur J Pharmacol 2023; 949:175726. [PMID: 37062503 DOI: 10.1016/j.ejphar.2023.175726] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 04/03/2023] [Accepted: 04/14/2023] [Indexed: 04/18/2023]
Abstract
Cholesterol is a key component of the cell membrane that impacts the permeability, fluidity, and functions of membrane-bound proteins. It also participates in synaptogenesis, synaptic function, axonal growth, dendrite outgrowth, and microtubule stability. Cholesterol biosynthesis and metabolism are in balance in the brain. Its metabolism in the brain is mediated mainly by CYP46A1 or cholesterol 24-hydroxylase. It is responsible for eliminating about 80% of the cholesterol excess from the human brain. CYP46A1 converts cholesterol to 24S-hydroxycholesterol (24HC) that readily crosses the blood-brain barrier and reaches the liver for the final elimination process. Studies show that cholesterol and 24HC levels change during neurological diseases and conditions. So, it was hypothesized that inhibition or activation of CYP46A1 would be an effective therapeutic strategy. Accordingly, preclinical studies, using genetic and pharmacological interventions, assessed the role of CYP46A1 in main neurodegenerative disorders such as Parkinson's disease, Huntington's disease, Alzheimer's disease, multiple sclerosis, spinocerebellar ataxias, and amyotrophic lateral sclerosis. In addition, its role in seizures and brain injury was evaluated. The recent development of soticlestat, as a selective and potent CYP46A1 inhibitor, with significant anti-seizure effects in preclinical and clinical studies, suggests the importance of this target for future drug developments. Previous studies have shown that both activation and inhibition of CYP46A1 are of therapeutic value. This article, using recent studies, highlights the role of CYP46A1 in various brain diseases and insults.
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Affiliation(s)
- Mohaddeseh Sadat Alavi
- Pharmacological Research Center of Medicinal Plants, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Gholamreza Karimi
- Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Ali Roohbakhsh
- Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
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Lu F, Fan S, Romo AR, Xu D, Ferriero DM, Jiang X. Serum 24S-hydroxycholesterol predicts long-term brain structural and functional outcomes after hypoxia-ischemia in neonatal mice. J Cereb Blood Flow Metab 2021; 41:312-323. [PMID: 32169014 PMCID: PMC8369995 DOI: 10.1177/0271678x20911910] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The major pathway of brain cholesterol turnover relies on its hydroxylation into 24S-hydroxycholesterol (24S-HC) using brain-specific cytochrome P450 46A1 (CYP46A1). 24S-HC produced exclusively in the brain normally traverses the blood-brain barrier to enter the circulation to the liver for excretion; therefore, the serum 24S-HC level is an indication of cholesterol metabolism in the brain. We recently reported an upregulation of CYP46A1 following hypoxia-ischemia (HI) in the neonatal mouse brain and a correlation between serum 24S-HC levels and acute brain damage. Here, we performed a longitudinal study to investigate whether the serum 24S-HC concentrations predict long-term brain structural and functional outcomes. In postnatal day 9 mice subjected to HI, the serum 24S-HC levels increased at 6 h and 24 h after HI and correlated with the infarct volumes measured histologically or by T2-weighted MRI. The 24 h levels were associated with white matter volume loss quantified by MBP immunostaining and luxol fast blue staining. The animals with higher serum 24S-HC at 6 h and 24 h corresponded to those with more severe motor and cognitive deficits at 35-40 days after HI. These data suggest that 24S-HC could be a novel and early blood biomarker for severity of neonatal HI brain damage and associated functional impairments.
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Affiliation(s)
- Fuxin Lu
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Shujuan Fan
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Andrea R Romo
- University of California Berkeley, Berkeley, CA, USA
| | - Duan Xu
- Department of Radiology, University of California San Francisco, San Francisco, CA, USA
| | - Donna M Ferriero
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA.,Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
| | - Xiangning Jiang
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
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4
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Pleiotropic effects of statins on brain cells. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183340. [PMID: 32387399 DOI: 10.1016/j.bbamem.2020.183340] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 05/01/2020] [Accepted: 05/01/2020] [Indexed: 01/06/2023]
Abstract
Starting with cholesterol homeostasis, the first part of the review addresses various aspects of cholesterol metabolism in neuronal and glial cells and the mutual crosstalk between the two cell types, particularly the transport of cholesterol from its site of synthesis to its target loci in neuronal cells, discussing the multiple mechanistic aspects and transporter systems involved. Statins are next analyzed from the point of view of their chemical structure and its impingement on their pharmacological properties and permeability through cell membranes and the blood-brain barrier in particular. The following section then discusses the transcriptional effects of statins and the changes they induce in brain cell genes associated with a variety of processes, including cell growth, signaling and trafficking, uptake and synthesis of cholesterol. We review the effects of statins at the cellular level, analyzing their impact on the cholesterol composition of the nerve and glial cell plasmalemma, neurotransmitter receptor mobilization, myelination, dendritic arborization of neurons, synaptic vesicle release, and cell viability. Finally, the role of statins in disease is exemplified by Alzheimer and Parkinson diseases and some forms of epilepsy, both in animal models and in the human form of these pathologies.
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Petrov AM, Lam M, Mast N, Moon J, Li Y, Maxfield E, Pikuleva IA. CYP46A1 Activation by Efavirenz Leads to Behavioral Improvement without Significant Changes in Amyloid Plaque Load in the Brain of 5XFAD Mice. Neurotherapeutics 2019; 16:710-724. [PMID: 31062296 PMCID: PMC6694340 DOI: 10.1007/s13311-019-00737-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Efavirenz, the FDA-approved anti-retroviral medication, is evaluated in the clinical trial in patients with mild cognitive impairment or early dementia due to Alzheimer's disease. Efavirenz is assessed for activation of cytochrome P450 46A1 (CYP46A1), a CNS-specific enzyme that converts cholesterol to 24-hydroxycholesterol. Cholesterol 24-hydroxylation is the major pathway for brain cholesterol removal, and a mechanism that controls brain cholesterol turnover. The present study tested efavirenz on 5XFAD mice (an Alzheimer's model) at a very low daily dose of 0.1 mg/kg body weight. Efavirenz treatment started from three months of age, after amyloid plague appearance, and continued for 6 months. This treatment led to CYP46A1 activation in the brain, enhancement of brain cholesterol turnover, behavioral improvements, reduction in microglia activation but increased astrocyte reactivity. The levels of the soluble and insoluble amyloid 40 and 42 peptides were unchanged while the number and area of the dense core amyloid plaques were slightly decreased. The measurements of the brain levels of several pre- and post-synaptic proteins (Munc13-1, PSD-95, gephyrin, synaptophysin, synapsin-1, and calbindin-D28k) suggested efavirenz effect at the synaptic level. Efavirenz treatment in the present work seems to represent a model of behavioral and other improvements independent of the levels of the amyloid peptides and provides insight into potential outcomes of the future clinical trial.
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Affiliation(s)
- Alexey M Petrov
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Morrie Lam
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Natalia Mast
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Jean Moon
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Yong Li
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Erin Maxfield
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Irina A Pikuleva
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA.
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Petrov AM, Mast N, Li Y, Pikuleva IA. The key genes, phosphoproteins, processes, and pathways affected by efavirenz-activated CYP46A1 in the amyloid-decreasing paradigm of efavirenz treatment. FASEB J 2019; 33:8782-8798. [PMID: 31063705 DOI: 10.1096/fj.201900092r] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Efavirenz (EFV) is an anti-HIV drug, and cytochrome P450 46A1 (CYP46A1) is the major brain cholesterol hydroxylase. Previously, we discovered that EFV activates CYP46A1 and improves behavioral performance in 5XFAD mice, an Alzheimer's disease model. Herein, the unbiased omics and other approaches were used to study 5XFAD mice in the amyloid-decreasing paradigm of CYP46A1 activation by EFV. These approaches revealed increases in the brain levels of postsynaptic density protein 95, gephyrin, synaptophysin, synapsin, glial fibrillary acidic protein, and CYP46A1 and documented altered expression and phosphorylation of 66 genes and 77 proteins, respectively. The data obtained pointed to EFV effects at the synaptic level, plasmin-depended amyloid clearance, inflammation and microglia phenotype, oxidative stress and cellular hypoxia, autophagy and ubiquitin-proteasome systems as well as apoptosis. These effects could be realized in part via changes in the Ca2+-, small GTPase, and catenin signaling. A model is proposed, in which CYP46A1-dependent lipid raft rearrangement and subsequent decrease of protein phosphorylation are central in EFV effects and explain behavioral improvements in EFV-treated 5XFAD mice.-Petrov, A. M., Mast, N., Li, Y., Pikuleva, I. A. The key genes, phosphoproteins, processes, and pathways affected by efavirenz-activated CYP46A1 in the amyloid-decreasing paradigm of efavirenz treatment.
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Affiliation(s)
- Alexey M Petrov
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Natalia Mast
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Yong Li
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Irina A Pikuleva
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
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Zhu Z, Hu Y, Zhou Y, Zhang Y, Yu L, Tao L, Guo A, Fang Q. Macrophage Migration Inhibitory Factor Promotes Chemotaxis of Astrocytes through Regulation of Cholesterol 25-Hydroxylase Following Rat Spinal Cord Injury. Neuroscience 2019; 408:349-360. [PMID: 31026565 DOI: 10.1016/j.neuroscience.2019.04.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 03/29/2019] [Accepted: 04/08/2019] [Indexed: 11/25/2022]
Abstract
Oxysterol derived from cholesterol metabolism is involved in the inflammatory activation, and consequently in development of major chronic diseases. Multiple cytokines have been found to induce the expression of cholesterol metabolism-related enzymes. Several studies have shown that the protein level of cholesterol-25-hydroxylase (CH25H) is remarkably increased in response to injury of central nervous system (CNS), but little is known about the mechanisms of cytokine-induced expression of CH25H in specific cell types, and the resultant effects. In the present study, we demonstrated that ch25h expression was significantly upregulated in the astrocytes of rat injured spinal cord, in parallel with those of MIF. Administration of MIF inhibitor 4-IPP in the lesion sites attenuated injury-induced ch25h expression. MIF facilitated ch25h expression of astrocytes through interaction with CD74 membrane receptor, which in turn promoted production of chemokines, as identified by transcriptome profiles. MIF-induced release of oxysterol 25-hydroxycholesterol (25-HC) from astrocytes affects cell migration, but inhibited cell viability in dose-dependent manner, suggesting that MIF aggravates progressive neuropathology through regulation of cholesterol metabolism following CNS injury. These results have provided a novel mechanism and a potential therapeutic strategy for injured CNS.
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Affiliation(s)
- Zhenjie Zhu
- Department of Neurology, The First Affiliated Hospital of Soochow University, Suzhou 215006, PR China; Department of Rehabilitation Medicine, Affiliated Hospital of Nantong University, Nantong 226001, PR China
| | - Yuming Hu
- Department of Rehabilitation Medicine, Affiliated Hospital of Nantong University, Nantong 226001, PR China
| | - Yue Zhou
- Department of Rehabilitation Medicine, Affiliated Hospital of Nantong University, Nantong 226001, PR China
| | - Yuxin Zhang
- Department of Rehabilitation Medicine, Affiliated Hospital of Nantong University, Nantong 226001, PR China
| | - Liqiang Yu
- Department of Neurology, The First Affiliated Hospital of Soochow University, Suzhou 215006, PR China.
| | - Lihong Tao
- Department of Neurology, The Affiliated Hospital of Yangzhou University, Yangzhou 225012, PR China
| | - Aisong Guo
- Department of Rehabilitation Medicine, Affiliated Hospital of Nantong University, Nantong 226001, PR China
| | - Qi Fang
- Department of Neurology, The First Affiliated Hospital of Soochow University, Suzhou 215006, PR China.
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Lu F, Zhu J, Guo S, Wong BJ, Chehab FF, Ferriero DM, Jiang X. Upregulation of cholesterol 24-hydroxylase following hypoxia-ischemia in neonatal mouse brain. Pediatr Res 2018; 83:1218-1227. [PMID: 29718007 PMCID: PMC6019156 DOI: 10.1038/pr.2018.49] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 03/02/2018] [Indexed: 01/07/2023]
Abstract
BackgroundMaintenance of cholesterol homeostasis is crucial for brain development. Brain cholesterol relies on de novo synthesis and is cleared primarily by conversion to 24S-hydroxycholesterol (24S-HC) with brain-specific cholesterol 24-hydroxylase (CYP46A1). We aimed to investigate the impact of hypoxia-ischemia (HI) on brain cholesterol metabolism in the neonatal mice.MethodsPostnatal day 9 C57BL/6 pups were subjected to HI using the Vannucci model. CYP46A1 expression was assessed with western blotting and its cellular localization was determined using immunofluorescence staining. The amount of brain cholesterol, 24S-HC in the cortex and in the serum, was measured with enzyme-linked immunosorbent assay (ELISA).ResultsThere was a transient cholesterol loss at 6 h after HI. CYP46A1 was significantly upregulated at 6 and 24 h following HI with a concomitant increase of 24S-HC in the ipsilateral cortex and in the serum. The serum levels of 24S-HC correlated with those in the brain, as well as with necrotic and apoptotic cell death evaluated by the expression of spectrin breakdown products and cleaved caspase-3 at 6 and 24 h after HI.ConclusionEnhanced cholesterol turnover by activation of CYP46A1 represents disrupted brain cholesterol homeostasis early after neonatal HI. 24S-HC might be a novel blood biomarker for severity of hypoxic-ischemic encephalopathy with potential clinical application.
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Affiliation(s)
- Fuxin Lu
- Department of Pediatrics, University of California San Francisco, San Francisco, CA
| | - Jun Zhu
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA
| | - Selena Guo
- Dougherty Valley High School, San Ramon, CA
| | | | - Farid F. Chehab
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA
| | - Donna M. Ferriero
- Department of Pediatrics, University of California San Francisco, San Francisco, CA,Department of Neurology, University of California San Francisco, San Francisco, CA
| | - Xiangning Jiang
- Department of Pediatrics, University of California San Francisco, San Francisco, CA,Corresponding author: Xiangning Jiang, Department of Pediatrics, University of California, San Francisco 675 Nelson Rising Lane Room 494, San Francisco, CA 94158 Phone: 415-502-7278 Fax: 415-502-7325
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Expression profiles of cholesterol metabolism-related genes are altered during development of experimental autoimmune encephalomyelitis in the rat spinal cord. Sci Rep 2017; 7:2702. [PMID: 28578430 PMCID: PMC5457442 DOI: 10.1038/s41598-017-02638-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 04/12/2017] [Indexed: 12/04/2022] Open
Abstract
Increased evidence suggests that dysregulation of cholesterol metabolism may be a key event contributing to progression of multiple sclerosis (MS). Using an experimental autoimmune encephalomyelitis (EAE) model of MS we revealed specific changes in the mRNA and protein expression of key molecules involved in the maintaining of cholesterol homeostasis in the rat spinal cord: 3-hydroxy-3-methylglutaryl-coenzyme-A reductase (HMGCR), apolipoprotein E (ApoE) and cholesterol 24-hydroxylase (CYP46A1) during the course of disease. The presence of myelin lipid debris was seen only at the peak of EAE in demyelination loci being efficiently removed during the recovery period. Since CYP46A1 is responsible for removal of cholesterol excess, we performed a detailed profiling of CYP46A1 expression and revealed regional and temporal specificities in its distribution. Double immunofluorescence staining demonstrated CYP46A1 localization with neurons, infiltrated macrophages, microglia and astrocytes in the areas of demyelination, suggesting that these cells play a role in cholesterol turnover in EAE. We propose that alterations in the regulation of cholesterol metabolism at the onset and peak of EAE may add to the progression of disease, while during the recovery period may have beneficial effects contributing to the regeneration of myelin sheath and restoration of neuronal function.
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Moutinho M, Nunes MJ, Rodrigues E. Cholesterol 24-hydroxylase: Brain cholesterol metabolism and beyond. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1911-1920. [PMID: 27663182 DOI: 10.1016/j.bbalip.2016.09.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/05/2016] [Accepted: 09/16/2016] [Indexed: 01/19/2023]
Abstract
Dysfunctions in brain cholesterol homeostasis have been extensively related to brain disorders. The major elimination pathway of brain cholesterol is its hydroxylation into 24 (S)-hydroxycholesterol by the cholesterol 24-hydroxylase (CYP46A1). Interestingly, there seems to be an association between CYP46A1 and high-order brain functions, in a sense that increased expression of this hydroxylase improves cognition, while a reduction leads to a poor cognitive performance. Moreover, increasing amount of epidemiological, biochemical and molecular evidence, suggests that CYP46A1 has a role in the pathogenesis or progression of neurodegenerative disorders, in which up-regulation of this enzyme is clearly beneficial. However, the mechanisms underlying these effects are poorly understood, which highlights the importance of studies that further explore the role of CYP46A1 in the central nervous system. In this review we summarize the major findings regarding CYP46A1, and highlight the several recently described pathways modulated by this enzyme from a physiological and pathological perspective, which might account for novel therapeutic strategies for neurodegenerative disorders.
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Affiliation(s)
- Miguel Moutinho
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Portugal, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Maria João Nunes
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Portugal, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Elsa Rodrigues
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Portugal, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal.
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The impairment of cholesterol metabolism in Huntington disease. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:1095-105. [DOI: 10.1016/j.bbalip.2014.12.018] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 12/19/2014] [Accepted: 12/21/2014] [Indexed: 02/02/2023]
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Filomenko R, Fourgeux C, Bretillon L, Gambert-Nicot S. Oxysterols: Influence on plasma membrane rafts microdomains and development of ocular diseases. Steroids 2015; 99:259-65. [PMID: 25683893 DOI: 10.1016/j.steroids.2015.02.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 01/26/2015] [Accepted: 02/02/2015] [Indexed: 01/27/2023]
Abstract
Oxidation of cholesterol into oxysterols is a major way of elimination of cholesterol from the liver and extrahepatic tissues, including the brain and the retina. Oxysterols are involved in various cellular processes. Numerous links have been established between oxysterols and several disorders such as neurodegenerative pathologies, retinopathies and atherosclerosis. Different components of the lipid layer such as sphingolipids, sterols and proteins participate to membrane fluidity and forme lipid rafts microdomains. Few data are available on the links between lipids rafts and oxysterols. The purpose of this review is to suggest the potential role of lipid rafts microdomains in the development of retinopathies with special emphasis and opening perspectives of their interactions with oxysterols. Actually cholesterol oxidation mechanism may have deleterious effect on its ability to support rafts formation .This review suggest that the effect of oxysterols of lipid rafts would probably depend on the oxysterol molecule and cell type.
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Affiliation(s)
- Rodolphe Filomenko
- INRA, UMR1324 Centre des Sciences du Goût et de l'Alimentation, Equipe Œil, Nutrition et Signalisation Cellulaire, F-21000 Dijon, France; CNRS, UMR6265 Centre des Sciences du Goût et de l'Alimentation, F-21000 Dijon, France; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation, F-21000 Dijon, France
| | - Cynthia Fourgeux
- INRA, UMR1324 Centre des Sciences du Goût et de l'Alimentation, Equipe Œil, Nutrition et Signalisation Cellulaire, F-21000 Dijon, France; CNRS, UMR6265 Centre des Sciences du Goût et de l'Alimentation, F-21000 Dijon, France; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation, F-21000 Dijon, France
| | - Lionel Bretillon
- INRA, UMR1324 Centre des Sciences du Goût et de l'Alimentation, Equipe Œil, Nutrition et Signalisation Cellulaire, F-21000 Dijon, France; CNRS, UMR6265 Centre des Sciences du Goût et de l'Alimentation, F-21000 Dijon, France; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation, F-21000 Dijon, France.
| | - Ségolène Gambert-Nicot
- INRA, UMR1324 Centre des Sciences du Goût et de l'Alimentation, Equipe Œil, Nutrition et Signalisation Cellulaire, F-21000 Dijon, France; CNRS, UMR6265 Centre des Sciences du Goût et de l'Alimentation, F-21000 Dijon, France; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation, F-21000 Dijon, France; CHU Dijon, Service de Biochimie Clinique, F-21000 Dijon, France
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Inhibiting ACAT1/SOAT1 in microglia stimulates autophagy-mediated lysosomal proteolysis and increases Aβ1-42 clearance. J Neurosci 2015; 34:14484-501. [PMID: 25339759 DOI: 10.1523/jneurosci.2567-14.2014] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Acyl-CoA:cholesterol acyltransferase 1 (ACAT1) is a resident endoplasmic reticulum enzyme that prevents the buildup of cholesterol in membranes by converting it to cholesterol esters. Blocking ACAT1 pharmacologically or by Acat1 gene knock-out (KO) decreases amyloidopathy in mouse models for Alzheimer's disease. However, the beneficial actions of ACAT1 blockage to treat Alzheimer's disease remained not well understood. Microglia play essential roles in the proteolytic clearance of amyloid β (Aβ) peptides. Here we show that Acat1 gene KO in mouse increases phagocytic uptake of oligomeric Aβ1-42 and stimulates lysosomal Aβ1-42 degradation in cultured microglia and in vivo. Additional results show that Acat1 gene KO or a specific ACAT1 inhibitor K604 stimulates autophagosome formation and transcription factor EB-mediated lysosomal proteolysis. Surprisingly, the effect of ACAT1 blockage does not alter mTOR signaling or endoplasmic reticulum stress response but can be modulated by agents that disrupt cholesterol biosynthesis. To our knowledge, our current study provides the first example that a small molecule (K604) can promote autophagy in an mTOR-independent manner to activate the coordinated lysosomal expression and regulation network. Autophagy is needed to degrade misfolded proteins/peptides. Our results implicate that blocking ACAT1 may provide a new way to benefit multiple neurodegenerative diseases.
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Lavrnja I, Trifunovic S, Ajdzanovic V, Pekovic S, Bjelobaba I, Stojiljkovic M, Milosevic V. Sensorimotor cortex ablation induces time-dependent response of ACTH cells in adult rats: behavioral, immunohistomorphometric and hormonal study. Physiol Behav 2013; 125:30-7. [PMID: 24291385 DOI: 10.1016/j.physbeh.2013.11.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 04/04/2013] [Accepted: 11/19/2013] [Indexed: 11/20/2022]
Abstract
Traumatic brain injury (TBI) represents a serious event with far reaching complications, including pituitary dysfunction. Pars distalis corticotropes (ACTH cells), that represent the active module of hypothalamo-pituitary-adrenocortical axis, seem to be affected as well. Since pituitary failure after TBI has been associated with neurobehavioral impairments the aim of this study was to evaluate the effects of TBI on recovery of motor functions, morphology and secretory activity of ACTH cells in the pituitary of adult rats. Wistar male rats, initially exposed to sensorimotor cortex ablation (SCA), were sacrificed at the 2nd, 7th, 14th and 30th days post-surgery (dps). A beam walking test was used to evaluate the recovery of motor functions. Pituitary glands and blood were collected for morphological and hormonal analyses. During the first two weeks post-injury increased recovery of locomotor function was detected, reaching almost the control value at day 30. SCA induces significant increase of pituitary weights compared to their time-matched controls. The volume of ACTH-immunopositive cells was reduced at the 7th dps, while at the 14th dps their volume was enlarged, in comparison to corresponding sham controls. Volume density of ACTH cells was increased only at 14th dps, while at day 30 this increase was insignificant. The plasma level of ACTH transiently increased after the injury. The most pronounced changes were observed at the 7th and 14th dps, and were followed by decrease toward control levels at the 30th dps. Thus, temporal changes in the hypothalamic-pituitary-adrenal axis after traumatic brain injury appear to correlate with the recovery process.
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Affiliation(s)
- Irena Lavrnja
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia.
| | - Svetlana Trifunovic
- Department of Cytology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Vladimir Ajdzanovic
- Department of Cytology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Sanja Pekovic
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Ivana Bjelobaba
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Mirjana Stojiljkovic
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Verica Milosevic
- Department of Cytology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
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15
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Cacciatore S, Tenori L. Brain cholesterol homeostasis in Wilson disease. Med Hypotheses 2013; 81:1127-9. [PMID: 24176139 DOI: 10.1016/j.mehy.2013.10.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 10/02/2013] [Accepted: 10/11/2013] [Indexed: 01/10/2023]
Abstract
Wilson disease (WD) is an autosomal recessive inherited disorder of copper (Cu) metabolism, resulting in pathological accumulation of Cu in many organs and tissues, predominantly in the liver and brain. There clearly is a close and complex relationship between Cu and the cholesterol's metabolic pathway; therefore any theory about the cholesterol metabolism in the brain of patients with WD must take it into account. The hypothesis presented in this paper is that the imbalance in cerebral copper homeostasis caused by WD may plays a key role in the derangement of the cholesterol homeostasis in the brain, and thus promoting the observed WD related neurological disorders.
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Affiliation(s)
- Stefano Cacciatore
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, 02115 Boston, MA, USA; Metabolomics Platform, Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders, Rovira i Virgili University, 43007 Tarragona, Spain.
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16
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Fourgeux C, Martine L, Pasquis B, Maire MA, Acar N, Creuzot-Garcher C, Bron A, Bretillon L. Steady-state levels of retinal 24S-hydroxycholesterol are maintained by glial cells intervention after elevation of intraocular pressure in the rat. Acta Ophthalmol 2012; 90:e560-7. [PMID: 22998629 DOI: 10.1111/j.1755-3768.2012.02490.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE Our previous studies suggested that CYP46A1 and 24S-hydroxycholesterol (24SOH) may be associated with glaucoma. Loss of CYP46A1-expressing retinal ganglion cells is involved in the activation of glia, and therefore possibly in the disbalance of cholesterol. In this context, the purpose of our present work was to emphasize the glial and longitudinal CYP46A1 expression after an interventional glaucoma-related stress triggered by elevated intraocular pressure (IOP). METHODS Sprague-Dawley rats were submitted to laser photocoagulation of the trabecular meshwork, limbus and episcleral veins in one eye to induce elevated IOP. Rats were euthanized at days 3, 14, 30 and 60 (n = 10 per time-point), and 24SOH was measured in plasma and retina by gas chromatography-mass spectrometry. CYP46A1 was quantified by Western blotting. Glial activation was assessed by glial fibrillary acidic protein immunoreactivity in Western blots and retinal cryosections. RESULTS Sustained high IOP was observed in experimental eyes from day 1 to day 21. Plasma MCP-1 and ICAM-1, quantified using multiplex assay kits, were increased at day 3. Glial activation was observed bilaterally at all time-points, at lower levels in contralateral eyes than in experimental eyes. In experimental retinas, CYP46A1 expression showed a transient increase at day 3 and then returned to baseline. Plasma and retinal 24SOH peaked at day 14 and 30, respectively. CONCLUSIONS These data show that CYP46A1 expression was induced early in response to retinal stress but remained constant at late time-points, reinforcing the constitutive role of CYP46A1 in maintaining cholesterol balance in neuronal tissues.
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Affiliation(s)
- Cynthia Fourgeux
- INRA, UMR1324 CSGA, Eye and Nutrition Research Group, Dijon, France
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Leoni V, Caccia C. 24S-hydroxycholesterol in plasma: a marker of cholesterol turnover in neurodegenerative diseases. Biochimie 2012; 95:595-612. [PMID: 23041502 DOI: 10.1016/j.biochi.2012.09.025] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 09/20/2012] [Indexed: 01/09/2023]
Abstract
Brain cholesterol is mainly involved in the cell membrane structure, in signal transduction, neurotransmitter release, synaptogenesis and membrane trafficking. Impairment of brain cholesterol metabolism was described in neurodegenerative diseases, such as Multiple Sclerosis, Alzheimer and Huntington Diseases. Since the blood-brain barrier efficiently prevents cholesterol uptake from the circulation into the brain, de novo synthesis is responsible for almost all cholesterol present there. Cholesterol is converted into 24S-hydroxycholesterol (24OHC) by cholesterol 24-hydroxylase (CYP46A1) expressed in neural cells. Plasma concentration of 24OHC depends upon the balance between cerebral production and hepatic elimination and is related to the number of metabolically active neurons in the brain. Factors affecting brain cholesterol turnover and liver elimination of oxysterols, together with the metabolism of plasma lipoproteins, genetic background, nutrition and lifestyle habits were found to significantly affect its plasma levels. Either increased or decreased plasma 24OHC concentrations were described in patients with neurodegenerative diseases. A group of evidence suggests that reduced levels of 24OHC are related to the loss of metabolically active cells and the degree of brain atrophy. Inflammation, dysfunction of BBB, increased cholesterol turnover might counteract this tendency resulting in increased levels or, in some cases, in unsignificant changes. The study of plasma 24OHC is likely to offer an insight about brain cholesterol turnover with a limited diagnostic power.
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Affiliation(s)
- Valerio Leoni
- Laboratory of Clinical Pathology and Medical Genetics, Foundation IRCCS Institute of Neurology Carlo Besta, Milan, Italy.
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Hübner S, Efthymiadis A. Histochemistry and cell biology: the annual review 2010. Histochem Cell Biol 2011; 135:111-40. [PMID: 21279376 DOI: 10.1007/s00418-011-0781-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2011] [Indexed: 10/18/2022]
Abstract
This review summarizes recent advances in histochemistry and cell biology which complement and extend our knowledge regarding various aspects of protein functions, cell and tissue biology, employing appropriate in vivo model systems in conjunction with established and novel approaches. In this context several non-expected results and discoveries were obtained which paved the way of research into new directions. Once the reader embarks on reading this review, it quickly becomes quite obvious that the studies contribute not only to a better understanding of fundamental biological processes but also provide use-oriented aspects that can be derived therefrom.
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Affiliation(s)
- Stefan Hübner
- Institute of Anatomy and Cell Biology, University of Würzburg, Koellikerstrasse 6, 97070 Würzburg, Germany.
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