1
|
Bouyakdan K, Manceau R, Robb JL, Rodaros D, Fulton S, Alquier T. Role of astroglial ACBP in energy metabolism flexibility and feeding responses to metabolic challenges in male mice. J Neuroendocrinol 2022; 34:e13218. [PMID: 36471907 DOI: 10.1111/jne.13218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/26/2022] [Accepted: 11/10/2022] [Indexed: 11/19/2022]
Abstract
Acyl-CoA binding protein (ACBP), also known as diazepam binding inhibitor (DBI), has recently emerged as a hypothalamic and brainstem gliopeptide regulating energy balance. Previous work has shown that the ACBP-derived octadecaneuropeptide exerts strong anorectic action via proopiomelanocortin (POMC) neuron activation and the melanocortin-4 receptor. Importantly, targeted ACBP loss-of-function in astrocytes promotes hyperphagia and diet-induced obesity while its overexpression in arcuate astrocytes reduces feeding and body weight. Despite this knowledge, the role of astroglial ACBP in adaptive feeding and metabolic responses to acute metabolic challenges has not been investigated. Using different paradigms, we found that ACBP deletion in glial fibrillary acidic protein (GFAP)-positive astrocytes does not affect weight loss when obese male mice are transitioned from a high fat diet to a chow diet, nor metabolic parameters in mice fed with a normal chow diet (e.g., energy expenditure, body temperature) during fasting, cold exposure and at thermoneutrality. In contrast, astroglial ACBP deletion impairs meal pattern and feeding responses during refeeding after a fast and during cold exposure, thereby showing that ACBP is required to stimulate feeding in states of increased energy demand. These findings challenge the general view that astroglial ACBP exerts anorectic effects and suggest that regulation of feeding by ACBP is dependent on metabolic status.
Collapse
Affiliation(s)
- Khalil Bouyakdan
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Romane Manceau
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Josephine L Robb
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Demetra Rodaros
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Stephanie Fulton
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Thierry Alquier
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| |
Collapse
|
2
|
Bouyakdan K, Taïb B, Budry L, Zhao S, Rodaros D, Neess D, Mandrup S, Faergeman NJ, Alquier T. A novel role for central ACBP/DBI as a regulator of long-chain fatty acid metabolism in astrocytes. J Neurochem 2015; 133:253-65. [PMID: 25598214 DOI: 10.1111/jnc.13035] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 12/15/2014] [Accepted: 01/08/2015] [Indexed: 12/29/2022]
Abstract
Acyl-CoA-binding protein (ACBP) is a ubiquitously expressed protein that binds intracellular acyl-CoA esters. Several studies have suggested that ACBP acts as an acyl-CoA pool former and regulates long-chain fatty acids (LCFA) metabolism in peripheral tissues. In the brain, ACBP is known as Diazepam-Binding Inhibitor, a secreted peptide acting as an allosteric modulator of the GABAA receptor. However, its role in central LCFA metabolism remains unknown. In the present study, we investigated ACBP cellular expression, ACBP regulation of LCFA intracellular metabolism, FA profile, and FA metabolism-related gene expression using ACBP-deficient and control mice. ACBP was mainly found in astrocytes with high expression levels in the mediobasal hypothalamus. We demonstrate that ACBP deficiency alters the central LCFA-CoA profile and impairs unsaturated (oleate, linolenate) but not saturated (palmitate, stearate) LCFA metabolic fluxes in hypothalamic slices and astrocyte cultures. In addition, lack of ACBP differently affects the expression of genes involved in FA metabolism in cortical versus hypothalamic astrocytes. Finally, ACBP deficiency increases FA content and impairs their release in response to palmitate in hypothalamic astrocytes. Collectively, these findings reveal for the first time that central ACBP acts as a regulator of LCFA intracellular metabolism in astrocytes. Acyl-CoA-binding protein (ACBP) or diazepam-binding inhibitor is a secreted peptide acting centrally as a GABAA allosteric modulator. Using brain slices, cortical, and hypothalamic astrocyte cultures from ACBP KO mice, we demonstrate that ACBP mainly localizes in astrocytes and regulates unsaturated but not saturated long-chain fatty acids (LCFA) metabolism. In addition, ACBP deficiency alters FA metabolism-related genes and results in intracellular FA accumulation while affecting their release. Our results support a novel role for ACBP in brain lipid metabolism. FA, fatty acids; KO, knockout; PL, phospholipids; TAG, triacylglycerol.
Collapse
Affiliation(s)
- Khalil Bouyakdan
- Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Universite de Montreal (CRCHUM), Montreal, Quebec, Canada; Department of Biochemistry, University of Montreal, Montreal, Quebec, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Gach K, Belkacemi O, Lefranc B, Perlikowski P, Masson J, Walet-Balieu ML, Do-Rego JC, Galas L, Schapman D, Lamtahri R, Tonon MC, Vaudry D, Chuquet J, Leprince J. Detection, characterization and biological activities of [bisphospho-thr3,9]ODN, an endogenous molecular form of ODN released by astrocytes. Neuroscience 2015; 290:472-84. [PMID: 25639232 DOI: 10.1016/j.neuroscience.2015.01.045] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Revised: 12/29/2014] [Accepted: 01/05/2015] [Indexed: 11/23/2022]
Abstract
Astrocytes synthesize and release endozepines, a family of regulatory neuropeptides, including diazepam-binding inhibitor (DBI) and its processing fragments such as the octadecaneuropeptide (ODN). At the molecular level, ODN interacts with two types of receptors, i.e. it acts as an inverse agonist of the central-type benzodiazepine receptor (CBR), and as an agonist of a G protein-coupled receptor (GPCR). ODN exerts a wide range of biological effects mediated through these two receptors and, in particular, it regulates astrocyte activity through an autocrine/paracrine mechanism involving the metabotropic receptor. More recently, it has been shown that Müller glial cells secrete phosphorylated DBI and that bisphosphorylated ODN ([bisphospho-Thr(3,9)]ODN, bpODN) has a stronger affinity for CBR than ODN. The aim of the present study was thus to investigate whether bpODN is released by mouse cortical astrocytes and to compare its potency to ODN. Using a radioimmunoassay and mass spectrometry analysis we have shown that bpODN as well as ODN were released in cultured astrocyte supernatants. Both bpODN and ODN increased astrocyte calcium event frequency but in a very different range of concentration. Indeed, ODN stimulatory effect decreased at concentrations over 10(-10)M whereas bpODN increased the calcium event frequency at similar doses. In vivo effects of bpODN and ODN were analyzed in two behavioral paradigms involving either the metabotropic receptor (anorexia) or the CBR (anxiety). As previously described, ODN (100ng, icv) induced a significant reduction of food intake. Similar effect was achieved with bpODN but at a 10 times higher dose (1000 ng, icv). Similarly, and contrasting with our hypothesis, bpODN was also 10 times less potent than ODN to induce anxiety-related behavior in the elevated zero maze test. Thus, the present data do not support that phosphorylation of ODN is involved in receptor selectivity but indicate that it rather weakens ODN activity.
Collapse
|
4
|
Do Rego JL, Seong JY, Burel D, Leprince J, Vaudry D, Luu-The V, Tonon MC, Tsutsui K, Pelletier G, Vaudry H. Regulation of neurosteroid biosynthesis by neurotransmitters and neuropeptides. Front Endocrinol (Lausanne) 2012; 3:4. [PMID: 22654849 PMCID: PMC3356045 DOI: 10.3389/fendo.2012.00004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Accepted: 01/05/2012] [Indexed: 12/30/2022] Open
Abstract
The enzymatic pathways leading to the synthesis of bioactive steroids in the brain are now almost completely elucidated in various groups of vertebrates and, during the last decade, the neuronal mechanisms involved in the regulation of neurosteroid production have received increasing attention. This report reviews the current knowledge concerning the effects of neurotransmitters, peptide hormones, and neuropeptides on the biosynthesis of neurosteroids. Anatomical studies have been carried out to visualize the neurotransmitter- or neuropeptide-containing fibers contacting steroid-synthesizing neurons as well as the neurotransmitter, peptide hormones, or neuropeptide receptors expressed in these neurons. Biochemical experiments have been conducted to investigate the effects of neurotransmitters, peptide hormones, or neuropeptides on neurosteroid biosynthesis, and to characterize the type of receptors involved. Thus, it has been found that glutamate, acting through kainate and/or AMPA receptors, rapidly inactivates P450arom, and that melatonin produced by the pineal gland and eye inhibits the biosynthesis of 7α-hydroxypregnenolone (7α-OH-Δ(5)P), while prolactin produced by the adenohypophysis enhances the formation of 7α-OH-Δ(5)P. It has also been demonstrated that the biosynthesis of neurosteroids is inhibited by GABA, acting through GABA(A) receptors, and neuropeptide Y, acting through Y1 receptors. In contrast, it has been shown that the octadecaneuropetide ODN, acting through central-type benzodiazepine receptors, the triakontatetraneuropeptide TTN, acting though peripheral-type benzodiazepine receptors, and vasotocin, acting through V1a-like receptors, stimulate the production of neurosteroids. Since neurosteroids are implicated in the control of various neurophysiological and behavioral processes, these data suggest that some of the neurophysiological effects exerted by neurotransmitters and neuropeptides may be mediated via the regulation of neurosteroid production.
Collapse
Affiliation(s)
- Jean Luc Do Rego
- INSERMMont-Saint-Aignan France
- European Institute for Peptide Research, IFRMP 23, Regional Platform for Cell Imaging, PRIMACEN, University of RouenMont-Saint-Aignan, France
- International Associated Laboratory Samuel de ChamplainMont-Saint-Aignan, France
| | - Jae Young Seong
- Laboratory of G Protein-Coupled Receptors, Graduate School of Medicine, Korea University College of MedicineSeoul, Korea
| | - Delphine Burel
- INSERMMont-Saint-Aignan France
- European Institute for Peptide Research, IFRMP 23, Regional Platform for Cell Imaging, PRIMACEN, University of RouenMont-Saint-Aignan, France
- International Associated Laboratory Samuel de ChamplainMont-Saint-Aignan, France
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, INSERM U982, University of RouenMont-Saint-Aignan, France
| | - Jerôme Leprince
- INSERMMont-Saint-Aignan France
- European Institute for Peptide Research, IFRMP 23, Regional Platform for Cell Imaging, PRIMACEN, University of RouenMont-Saint-Aignan, France
- International Associated Laboratory Samuel de ChamplainMont-Saint-Aignan, France
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, INSERM U982, University of RouenMont-Saint-Aignan, France
| | - David Vaudry
- INSERMMont-Saint-Aignan France
- European Institute for Peptide Research, IFRMP 23, Regional Platform for Cell Imaging, PRIMACEN, University of RouenMont-Saint-Aignan, France
- International Associated Laboratory Samuel de ChamplainMont-Saint-Aignan, France
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, INSERM U982, University of RouenMont-Saint-Aignan, France
| | - Van Luu-The
- Research Center in Molecular Endocrinology, Oncology and Genetics, Laval University Hospital CenterQuébec, QC, Canada
| | - Marie-Christine Tonon
- INSERMMont-Saint-Aignan France
- European Institute for Peptide Research, IFRMP 23, Regional Platform for Cell Imaging, PRIMACEN, University of RouenMont-Saint-Aignan, France
- International Associated Laboratory Samuel de ChamplainMont-Saint-Aignan, France
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, INSERM U982, University of RouenMont-Saint-Aignan, France
| | - Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology, Waseda UniversityTokyo, Japan
- Center for Medical Life Science of Waseda UniversityTokyo, Japan
| | - Georges Pelletier
- Research Center in Molecular Endocrinology, Oncology and Genetics, Laval University Hospital CenterQuébec, QC, Canada
| | - Hubert Vaudry
- INSERMMont-Saint-Aignan France
- European Institute for Peptide Research, IFRMP 23, Regional Platform for Cell Imaging, PRIMACEN, University of RouenMont-Saint-Aignan, France
- International Associated Laboratory Samuel de ChamplainMont-Saint-Aignan, France
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, INSERM U982, University of RouenMont-Saint-Aignan, France
- *Correspondence: Hubert Vaudry, INSERM U982, European Institute for Peptide Research, IFRMP 23, University of Rouen, 76821 Mont-Saint-Aignan, France. e-mail:
| |
Collapse
|