1
|
Zorrilla Veloz RI, McKenzie T, Palacios BE, Hu J. Nuclear hormone receptors in demyelinating diseases. J Neuroendocrinol 2022; 34:e13171. [PMID: 35734821 PMCID: PMC9339486 DOI: 10.1111/jne.13171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 04/20/2022] [Accepted: 05/27/2022] [Indexed: 11/28/2022]
Abstract
Demyelination results from the pathological loss of myelin and is a hallmark of many neurodegenerative diseases. Despite the prevalence of demyelinating diseases, there are no disease modifying therapies that prevent the loss of myelin or promote remyelination. This review aims to summarize studies in the field that highlight the importance of nuclear hormone receptors in the promotion and maintenance of myelination and the relevance of nuclear hormone receptors as potential therapeutic targets for demyelinating diseases. These nuclear hormone receptors include the estrogen receptor, progesterone receptor, androgen receptor, vitamin D receptor, thyroid hormone receptor, peroxisome proliferator-activated receptor, liver X receptor, and retinoid X receptor. Pre-clinical studies in well-established animal models of demyelination have shown a prominent role of these nuclear hormone receptors in myelination through their promotion of oligodendrocyte maturation and development. The activation of the nuclear hormone receptors by their ligands also promotes the synthesis of myelin proteins and lipids in mouse models of demyelination. There are limited clinical studies that focus on how the activation of these nuclear hormone receptors could alleviate demyelination in patients with diseases such as multiple sclerosis (MS). However, the completed clinical trials have reported improved clinical outcome in MS patients treated with the ligands of some of these nuclear hormone receptors. Together, the positive results from both clinical and pre-clinical studies point to nuclear hormone receptors as promising therapeutic targets to counter demyelination.
Collapse
Affiliation(s)
- Rocío I Zorrilla Veloz
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Cancer Biology Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Takese McKenzie
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Neuroscience Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Bridgitte E Palacios
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Cancer Biology Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
- Neuroscience Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Jian Hu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Cancer Biology Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
- Neuroscience Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| |
Collapse
|
2
|
Strosznajder AK, Wójtowicz S, Jeżyna MJ, Sun GY, Strosznajder JB. Recent Insights on the Role of PPAR-β/δ in Neuroinflammation and Neurodegeneration, and Its Potential Target for Therapy. Neuromolecular Med 2020; 23:86-98. [PMID: 33210212 PMCID: PMC7929960 DOI: 10.1007/s12017-020-08629-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/28/2020] [Indexed: 02/07/2023]
Abstract
Peroxisome proliferator-activated receptor (PPAR) β/δ belongs to the family of hormone and lipid-activated nuclear receptors, which are involved in metabolism of long-chain fatty acids, cholesterol, and sphingolipids. Similar to PPAR-α and PPAR-γ, PPAR-β/δ also acts as a transcription factor activated by dietary lipids and endogenous ligands, such as long-chain saturated and polyunsaturated fatty acids, and selected lipid metabolic products, such as eicosanoids, leukotrienes, lipoxins, and hydroxyeicosatetraenoic acids. Together with other PPARs, PPAR-β/δ displays transcriptional activity through interaction with retinoid X receptor (RXR). In general, PPARs have been shown to regulate cell differentiation, proliferation, and development and significantly modulate glucose, lipid metabolism, mitochondrial function, and biogenesis. PPAR-β/δ appears to play a special role in inflammatory processes and due to its proangiogenic and anti-/pro-carcinogenic properties, this receptor has been considered as a therapeutic target for treating metabolic syndrome, dyslipidemia, carcinogenesis, and diabetes. Until now, most studies were carried out in the peripheral organs, and despite of its presence in brain cells and in different brain regions, its role in neurodegeneration and neuroinflammation remains poorly understood. This review is intended to describe recent insights on the impact of PPAR-β/δ and its novel agonists on neuroinflammation and neurodegenerative disorders, including Alzheimer’s and Parkinson’s, Huntington’s diseases, multiple sclerosis, stroke, and traumatic injury. An important goal is to obtain new insights to better understand the dietary and pharmacological regulations of PPAR-β/δ and to find promising therapeutic strategies that could mitigate these neurological disorders.
Collapse
Affiliation(s)
- Anna K Strosznajder
- Faculty of Medicine, Medical University of Bialystok, 1 Kilinskiego st., 15-089, Białystok, Poland
| | - Sylwia Wójtowicz
- Department of Cellular Signaling, Mossakowski Medical Research Centre Polish Academy of Sciences, 5 Pawińskiego st., 02-106, Warsaw, Poland
| | - Mieszko J Jeżyna
- Faculty of Medicine, Medical University of Bialystok, 1 Kilinskiego st., 15-089, Białystok, Poland
| | - Grace Y Sun
- Biochemistry Department, University of Missouri, Columbia, MO, 65211, USA
| | - Joanna B Strosznajder
- Department of Cellular Signaling, Mossakowski Medical Research Centre Polish Academy of Sciences, 5 Pawińskiego st., 02-106, Warsaw, Poland.
| |
Collapse
|
3
|
Pease LI, Clegg PD, Proctor CJ, Shanley DJ, Cockell SJ, Peffers MJ. Cross platform analysis of transcriptomic data identifies ageing has distinct and opposite effects on tendon in males and females. Sci Rep 2017; 7:14443. [PMID: 29089527 PMCID: PMC5663855 DOI: 10.1038/s41598-017-14650-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 10/13/2017] [Indexed: 01/21/2023] Open
Abstract
The development of tendinopathy is influenced by a variety of factors including age, gender, sex hormones and diabetes status. Cross platform comparative analysis of transcriptomic data elucidated the connections between these entities in the context of ageing. Tissue-engineered tendons differentiated from bone marrow derived mesenchymal stem cells from young (20-24 years) and old (54-70 years) donors were assayed using ribonucleic acid sequencing (RNA-seq). Extension of the experiment to microarray and RNA-seq data from tendon identified gender specific gene expression changes highlighting disparity with existing literature and published pathways. Separation of RNA-seq data by sex revealed underlying negative binomial distributions which increased statistical power. Sex specific de novo transcriptome assemblies generated fewer larger transcripts that contained miRNAs, lincRNAs and snoRNAs. The results identify that in old males decreased expression of CRABP2 leads to cell proliferation, whereas in old females it leads to cellular senescence. In conjunction with existing literature the results explain gender disparity in the development and types of degenerative diseases as well as highlighting a wide range of considerations for the analysis of transcriptomic data. Wider implications are that degenerative diseases may need to be treated differently in males and females because alternative mechanisms may be involved.
Collapse
Affiliation(s)
- Louise I Pease
- MRC - Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Liverpool, UK
| | - Peter D Clegg
- MRC - Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Liverpool, UK
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, The University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK
| | - Carole J Proctor
- MRC - Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Liverpool, UK
- Institute of Cellular Medicine, Newcastle University, Newcastle, NE2 4HH, UK
| | - Daryl J Shanley
- MRC - Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Liverpool, UK
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle, NE1 7RU, UK
| | - Simon J Cockell
- Faculty of Medical Sciences, Bioinformatics Support Unit, Framlington Place, Newcastle University, Newcastle, NE2 4HH, UK
| | - Mandy J Peffers
- MRC - Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Liverpool, UK.
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, The University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK.
| |
Collapse
|
4
|
Picklo MJ, Johnson L, Idso J. PPAR mRNA Levels Are Modified by Dietary n-3 Fatty Acid Restriction and Energy Restriction in the Brain and Liver of Growing Rats. J Nutr 2017; 147:161-169. [PMID: 27927977 DOI: 10.3945/jn.116.237107] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 07/07/2016] [Accepted: 11/15/2016] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Without dietary sources of n-3 (ω-3) long-chain polyunsaturated fatty acids (LCPUFAs), α-linolenic acid (ALA; 18:3n-3) is the precursor for docosahexaenoic acid (DHA; 22:6n-3). It is not known how energy restriction (ER) affects ALA conversion to DHA. OBJECTIVE We tested the hypothesis that ER reduces n-3 LCPUFA concentrations in tissues of growing rats fed diets replete with and deficient in ALA. METHODS Male Sprague-Dawley rats (23 d old) were provided AIN93G diets (4 wk) made with soybean oil (SO; ALA sufficient) or corn oil (CO; ALA deficient) providing 16% of energy as fat. For each dietary oil, ER rats were individually pair-fed 75% of another rat's ad libitum (AL) intake. Fatty acid (FA) concentrations in brain regions, liver, and plasma were analyzed. Expression of peroxisome proliferator-activated receptors (PPARs), uncoupling proteins (UCPs), and mitochondrial DNA was analyzed in the brain and liver. RESULTS AL rats consuming CO had a 65% lower concentration of n-3 docosapentaenoic acid (22:5n-3) and a 10% lower DHA concentration in the cerebral cortex and cerebellum than did the SO-AL group. ER did not alter cerebral n-3 LCPUFA status. Liver n-3 LCPUFA concentrations were reduced in rats fed CO compared with SO. ER reduced hepatic linoleic acid (18:2n-6), ALA, and arachidonic acid (20:4n-6) regardless of oil. ER and n-3 FA deficiency had independent effects on the mRNA levels of Pparα, Pparβ/δ, and Pparγ in the liver, cerebral cortex, and cerebellum. ER reduced Ucp3 mRNA by nearly 50% in the cerebral cortex, cerebellum, and liver, and Ucp5 mRNA was 30% lower in the cerebellum of rats receiving the CO diet. CONCLUSIONS Small perturbations in PUFA concentration and ER modify the mRNA levels of Ppar and Ucp in the juvenile rat brain. More research is needed to identify the long-term physiologic and behavioral impacts of ER and PUFA restriction in the juvenile brain.
Collapse
Affiliation(s)
- Matthew J Picklo
- USDA Agricultural Research Service Grand Forks Human Nutrition Research Center, Grand Forks, ND
| | - LuAnn Johnson
- USDA Agricultural Research Service Grand Forks Human Nutrition Research Center, Grand Forks, ND
| | - Joseph Idso
- USDA Agricultural Research Service Grand Forks Human Nutrition Research Center, Grand Forks, ND
| |
Collapse
|
5
|
Lee SJ, Wang S, Borschel W, Heyman S, Gyore J, Nichols CG. Secondary anionic phospholipid binding site and gating mechanism in Kir2.1 inward rectifier channels. Nat Commun 2013; 4:2786. [PMID: 24270915 PMCID: PMC3868208 DOI: 10.1038/ncomms3786] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 10/16/2013] [Indexed: 12/03/2022] Open
Abstract
Inwardly rectifying potassium (Kir) channels regulate multiple tissues. All Kir channels require interaction of phosphatidyl-4,5-bisphosphate (PIP2) at a crystallographically identified binding site, but an additional nonspecific secondary anionic phospholipid (PL(-)) is required to generate high PIP2 sensitivity of Kir2 channel gating. The PL(-)-binding site and mechanism are yet to be elucidated. Here we report docking simulations that identify a putative PL(-)-binding site, adjacent to the PIP2-binding site, generated by two lysine residues from neighbouring subunits. When either lysine is mutated to cysteine (K64C and K219C), channel activity is significantly decreased in cells and in reconstituted liposomes. Directly tethering K64C to the membrane by modification with decyl-MTS generates high PIP2 sensitivity in liposomes, even in the complete absence of PL(-)s. The results provide a coherent molecular mechanism whereby PL(-) interaction with a discrete binding site results in a conformational change that stabilizes the high-affinity PIP2 activatory site.
Collapse
Affiliation(s)
- Sun-Joo Lee
- Department of Cell Biology and Physiology and the Center for Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Shizhen Wang
- Department of Cell Biology and Physiology and the Center for Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - William Borschel
- Department of Cell Biology and Physiology and the Center for Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Sarah Heyman
- Department of Cell Biology and Physiology and the Center for Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Jacob Gyore
- Department of Cell Biology and Physiology and the Center for Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Colin G. Nichols
- Department of Cell Biology and Physiology and the Center for Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| |
Collapse
|
6
|
Kitson AP, Stroud CK, Stark KD. Elevated production of docosahexaenoic acid in females: potential molecular mechanisms. Lipids 2010; 45:209-24. [PMID: 20151220 DOI: 10.1007/s11745-010-3391-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Accepted: 01/15/2010] [Indexed: 01/25/2023]
Abstract
Observational evidence suggests that in populations consuming low levels of n-3 highly unsaturated fatty acids, women have higher blood levels of docosahexaenoic acid (DHA; 22:3n-6) as compared with men. Increased conversion of alpha-linolenic acid (ALA; 18:3n-3) to DHA by females has been confirmed in fatty acid stable isotope studies. This difference in conversion appears to be associated with estrogen and some evidence indicates that the expression of enzymes involved in synthesis of DHA from ALA, including desaturases and elongases, is elevated in females. An estrogen-associated effect may be mediated by peroxisome proliferator activated receptor-alpha (PPARalpha), as activation of this nuclear receptor increases the expression of these enzymes. However, because estrogens are weak ligands for PPARalpha, estrogen-mediated increases in PPARalpha activity likely occur through an indirect mechanism involving membrane-bound estrogen receptors and estrogen-sensitive G-proteins. The protein kinases activated by these receptors phosphorylate and increase the activity of PPARalpha, as well as phospholipase A(2) and cyclooxygenase 2 that increase the intracellular concentration of PPARalpha ligands. This review will outline current knowledge regarding elevated DHA production in females, as well as highlight interactions between estrogen signaling and PPARalpha activity that may mediate this effect.
Collapse
Affiliation(s)
- Alex P Kitson
- Laboratory of Nutritional and Nutraceutical Research, Department of Kinesiology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | | | | |
Collapse
|
7
|
Regulation of oligodendrocyte progenitor cell maturation by PPARδ: effects on bone morphogenetic proteins. ASN Neuro 2010; 2:e00025. [PMID: 20001953 PMCID: PMC2807733 DOI: 10.1042/an20090033] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Revised: 12/07/2009] [Accepted: 12/09/2009] [Indexed: 12/22/2022] Open
Abstract
In EAE (experimental autoimmune encephalomyelitis), agonists of PPARs (peroxisome proliferator-activated receptors) provide clinical benefit and reduce damage. In contrast with PPARγ, agonists of PPARδ are more effective when given at later stages of EAE and increase myelin gene expression, suggesting effects on OL (oligodendrocyte) maturation. In the present study we examined effects of the PPARδ agonist GW0742 on OPCs (OL progenitor cells), and tested whether the effects involve modulation of BMPs (bone morphogenetic proteins). We show that effects of GW0742 are mediated through PPARδ since no amelioration of EAE clinical scores was observed in PPARδ-null mice. In OPCs derived from E13 mice (where E is embryonic day), GW0742, but not the PPARγ agonist pioglitazone, increased the number of myelin-producing OLs. This was due to activation of PPARδ since process formation was reduced in PPARδ-null compared with wild-type OPCs. In both OPCs and enriched astrocyte cultures, GW0742 increased noggin protein expression; however, noggin mRNA was only increased in astrocytes. In contrast, GW0742 reduced BMP2 and BMP4 mRNA levels in OPCs, with lesser effects in astrocytes. These findings demonstrate that PPARδ plays a role in OPC maturation, mediated, in part, by regulation of BMP and BMP antagonists.
Collapse
|
8
|
Atshaves BP, McIntosh AL, Storey SM, Landrock KK, Kier AB, Schroeder F. High dietary fat exacerbates weight gain and obesity in female liver fatty acid binding protein gene-ablated mice. Lipids 2009; 45:97-110. [PMID: 20035485 DOI: 10.1007/s11745-009-3379-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Accepted: 11/24/2009] [Indexed: 01/01/2023]
Abstract
Since liver fatty acid binding protein (L-FABP) facilitates uptake/oxidation of long-chain fatty acids in cultured transfected cells and primary hepatocytes, loss of L-FABP was expected to exacerbate weight gain and/or obesity in response to high dietary fat. Male and female wild-type (WT) and L-FABP gene-ablated mice, pair-fed a defined isocaloric control or high fat diet for 12 weeks, consumed equal amounts of food by weight and kcal. Male WT mice gained weight faster than their female WT counterparts regardless of diet. L-FABP gene ablation enhanced weight gain more in female than male mice-an effect exacerbated by high fat diet. Dual emission X-ray absorptiometry revealed high-fat fed male and female WT mice gained mostly fat tissue mass (FTM). L-FABP gene ablation increased FTM in female, but not male, mice-an effect also exacerbated by high fat diet. Concomitantly, L-FABP gene ablation decreased serum beta-hydroxybutyrate in male and female mice fed the control diet and, even more so, on the high-fat diet. Thus, L-FABP gene ablation decreased fat oxidation and sensitized all mice to weight gain as whole body FTM and LTM-with the most gain observed in FTM of control vs high-fat fed female L-FABP null mice. Taken together, these results indicate loss of L-FABP exacerbates weight gain and/or obesity in response to high dietary fat.
Collapse
Affiliation(s)
- Barbara P Atshaves
- Department of Physiology and Pharmacology, Texas A&M University, TVMC, College Station, TX, 77843-4466, USA
| | | | | | | | | | | |
Collapse
|
9
|
Peroxisome Proliferator-Activated Receptor beta/delta in the Brain: Facts and Hypothesis. PPAR Res 2008; 2008:780452. [PMID: 19009042 PMCID: PMC2581793 DOI: 10.1155/2008/780452] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Accepted: 09/08/2008] [Indexed: 12/27/2022] Open
Abstract
peroxisome proliferator-activated receptors (PPARs) are nuclear receptors acting as lipid sensors. Besides its metabolic activity in peripheral organs, the PPAR beta/delta isotype is highly expressed in the brain and its deletion in mice induces a brain developmental defect. Nevertheless, exploration of PPARβ action in the central nervous system remains sketchy. The lipid content alteration observed in PPARβ null brains and the positive action of PPARβ agonists on oligodendrocyte differentiation, a process characterized by lipid accumulation, suggest that PPARβ acts on the fatty acids and/or cholesterol metabolisms in the brain. PPARβ could also regulate central inflammation and antioxidant mechanisms in the damaged brain. Even if not fully understood, the neuroprotective effect of PPARβ agonists highlights their potential benefit to treat various acute or chronic neurological disorders. In this perspective, we need to better understand the basic function of PPARβ in the brain. This review proposes different leads for future researches.
Collapse
|
10
|
Willis S, Samala R, Rosenberger TA, Borges K. Eicosapentaenoic and docosahexaenoic acids are not anticonvulsant or neuroprotective in acute mouse seizure models. Epilepsia 2008; 50:138-42. [PMID: 18637828 DOI: 10.1111/j.1528-1167.2008.01722.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), or vegetable oil (control) were added to standard rodent chow (6 g/kg) and fed to mice ad lib for 4 weeks to determine if polyunsaturated fatty acids (PUFA) are anticonvulsant or neuroprotective in mice. The seizure susceptibility of these mice was compared using the fluorothyl, pentylenetetrazole (PTZ), 6 Hz, and kainate models. We found that PUFA feeding significantly altered the fatty acid profile in both plasma and brain, but did not change seizure thresholds in the fluorothyl, PTZ, or 6 Hz models nor did it significantly alter seizure behavior or hippocampal damage following kainate injection. In conclusion, DHA or EPA feeding did not show anticonvulsant or neuroprotective activity in four acute seizure models. Chronic seizure models remain to be examined.
Collapse
Affiliation(s)
- Sarah Willis
- Department of Pharmaceutical Sciences, Texas Tech Health Sciences Center, School of Pharmacy, Amarillo, Texas, USA
| | | | | | | |
Collapse
|
11
|
Abstract
Obesity is a major public health concern and environmental factors are involved in its development. The hypothalamus is a primary site for the integration of signals for the regulation of energy homeostasis. Dysregulation of these pathways can lead to weight loss or gain. Some drugs in development can have favourable effects on body weight, acting on some of these pathways and leading to responses resulting in weight loss. Strategies for the management of weight reduction include exercise, diet, behavioural therapy, drug therapy and surgery. Investigational antiobesity medications can modulate energy homeostasis by stimulating catabolic or inhibiting anabolic pathways. Investigational drugs stimulating catabolic pathways consist of leptin, agonists of melanocortin receptor-4, 5-HT and dopamine; bupropion, growth hormone fragments, cholecystokinin subtype 1 receptor agonist, peptide YY3-36, oxyntomodulin, ciliary neurotrophic factor analogue, beta3-adrenergic receptor agonists, adiponectin derivatives and glucagon-like peptide-1. On the other hand, investigational drugs inhibiting anabolic pathways consist of the ghrelin receptor, neuropeptide Y receptor and melanin-concentrating hormone-1 antagonists; somatostatin analogues, peroxisome proliferator-activated receptor-gamma and -beta/delta antagonists, gastric emptying retardation agents, pancreatic lipase inhibitors, topiramate and cannabinoid-1 receptor antagonists. These differing approaches are reviewed and commented on in this article.
Collapse
MESH Headings
- Animals
- Anti-Obesity Agents/pharmacology
- Anti-Obesity Agents/therapeutic use
- Body Weight
- Drugs, Investigational/pharmacology
- Drugs, Investigational/therapeutic use
- Energy Metabolism
- Humans
- Hypothalamus/drug effects
- Hypothalamus/metabolism
- Leptin/genetics
- Leptin/pharmacology
- Leptin/therapeutic use
- Obesity/drug therapy
- Obesity/metabolism
- Peroxisome Proliferator-Activated Receptors/drug effects
- Peroxisome Proliferator-Activated Receptors/metabolism
- Randomized Controlled Trials as Topic
- Receptor, Melanocortin, Type 4/agonists
- Receptor, Melanocortin, Type 4/metabolism
- Receptor, Serotonin, 5-HT1B/metabolism
- Receptor, Serotonin, 5-HT2C/metabolism
- Receptors, G-Protein-Coupled/antagonists & inhibitors
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Ghrelin
- Receptors, Neuropeptide Y/antagonists & inhibitors
- Receptors, Neuropeptide Y/metabolism
- Recombinant Proteins/pharmacology
- Recombinant Proteins/therapeutic use
- Serotonin 5-HT1 Receptor Agonists
- Serotonin 5-HT2 Receptor Agonists
- Serotonin Receptor Agonists/pharmacology
- Serotonin Receptor Agonists/therapeutic use
Collapse
Affiliation(s)
- Marcio C Mancini
- Sao Paulo University, Obesity & Metabolic Syndrome Group of the Endocrinology & Metabology Service, Faculty of Medicine, Hospital das Clínicas, Sao Paulo, Brazil.
| | | |
Collapse
|
12
|
Polak PE, Kalinin S, Dello Russo C, Gavrilyuk V, Sharp A, Peters JM, Richardson J, Willson TM, Weinberg G, Feinstein DL. Protective effects of a peroxisome proliferator-activated receptor-beta/delta agonist in experimental autoimmune encephalomyelitis. J Neuroimmunol 2005; 168:65-75. [PMID: 16098614 DOI: 10.1016/j.jneuroim.2005.07.006] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Accepted: 07/08/2005] [Indexed: 12/01/2022]
Abstract
Agonists of the peroxisome proliferator-activated receptor gamma (PPARgamma) exert anti-inflammatory and anti-proliferative effects which led to testing of these drugs in experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis. In contrast, the effect of PPARdelta (PPARdelta) agonists in EAE is not yet known. We show that oral administration of the selective PPARdelta agonist GW0742 reduced clinical symptoms in C57BL/6 mice that had been immunized with encephalitogenic myelin oligodendrocyte glycoprotein (MOG) peptide. In contrast to previous results with PPARgamma agonists, GW0742 only modestly attenuated clinical symptoms when the drug was provided simultaneously with immunization, but a greater reduction was observed if administered during disease progression. Reduced clinical symptoms were accompanied by a reduction in the appearance of new cortical lesions, however cerebellar lesion load was not reduced. Treatment of T-cells with GW0742 either in vivo or in vitro did not reduce IFNgamma production; however GW0742 reduced astroglial and microglial inflammatory activation and IL-1beta levels in EAE brain. RTPCR analysis showed that GW0742 increased expression of some myelin genes. These data demonstrate that PPARdelta agonists, like other PPAR ligands, can exert protective actions in an autoimmune model of demyelinating disease.
Collapse
Affiliation(s)
- Paul E Polak
- Department of Anesthesiology, University of Illinois, & Jesse Brown Veteran's Affairs Research Division, Chicago, IL 60612, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Ibabe A, Bilbao E, Cajaraville MP. Expression of peroxisome proliferator-activated receptors in zebrafish (Danio rerio) depending on gender and developmental stage. Histochem Cell Biol 2004; 123:75-87. [PMID: 15616845 DOI: 10.1007/s00418-004-0737-2] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2004] [Indexed: 01/09/2023]
Abstract
Peroxisome proliferator-activated receptors (PPARs) are members of the superfamily of nuclear hormone receptors involved in embryo development and differentiation of several tissues in mammals. The aim of the present study was to investigate the possible differential expression of the three PPAR subtypes (PPARalpha, PPARbeta, and PPARgamma) in relation to gender and developmental stage in zebrafish. For this purpose PPAR expression was assessed by immunohistochemistry in 7-day-old larvae, 1-month-old juveniles, and 1-year-old adults. Additionally, the activity of peroxisomal acyl-CoA oxidase (AOX), a gene regulated by PPARs, and the volume density of catalase-immunolabeled liver peroxisomes (V(VP)) was examined. No significant gender-related differences were detected in the tissue distribution of the three PPAR subtypes or in peroxisomal AOX activity and V(VP). The percentage of PPARbeta-positive hepatocytes was significantly higher in females than in males suggesting a specific regulatory role of this subtype in female zebrafish. The three PPAR subtypes were already expressed at the larval stage, with a similar tissue distribution pattern to that found in adults. For all stages, PPARalpha and PPARgamma were expressed at higher levels than PPARbeta, and PPARbeta immunolabeling was stronger in juveniles than in larval or adult stages. The percentages of hepatocyte nuclei immunolabeled for PPARs was higher in early developmental stages than in adults, similarly to AOX activity and V(VP). In conclusion, our results indicate that PPAR expression, the activity of its target gene AOX, and peroxisomal biogenesis are developmentally modulated in zebrafish.
Collapse
Affiliation(s)
- Arantza Ibabe
- Biologia Zelularra eta Histologia Laborategia, Zoologia eta Animali Biologia Zelularra Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea/Universidad del País Vasco, 644 PK, 48080 Bilbo, Spain.
| | | | | |
Collapse
|
14
|
Reed KR, Sansom OJ, Hayes AJ, Gescher AJ, Winton DJ, Peters JM, Clarke AR. PPARdelta status and Apc-mediated tumourigenesis in the mouse intestine. Oncogene 2004; 23:8992-6. [PMID: 15480419 DOI: 10.1038/sj.onc.1208143] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Based on recent reports that peroxisome proliferator-activated receptor delta (PPARdelta) activation promotes tumourigenesis, we have investigated the role of this protein in Apc-mediated intestinal tumourigenesis. We demonstrate that the inactivation of Apc in the adult small intestine, while causing the expected nuclear accumulation of beta-catenin, does not cause the expected increase in PPARdelta mRNA or protein but conversely, the levels of PPARdelta mRNA and protein are lowered. Furthermore, we find that ApcMinPPARdelta-null mice exhibit an increased predisposition to intestinal tumourigenesis. Our data suggest that PPARdelta is not directly regulated by beta-catenin, and that inhibition of PPARdelta activity is unlikely to be an appropriate strategy for the chemoprevention or chemotherapy of intestinal malignancies.
Collapse
Affiliation(s)
- Karen R Reed
- Cardiff School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF103US, UK
| | | | | | | | | | | | | |
Collapse
|
15
|
Smith SA, Monteith GR, Robinson JA, Venkata NG, May FJ, Roberts-Thomson SJ. Effect of the peroxisome proliferator-activated receptor beta activator GW0742 in rat cultured cerebellar granule neurons. J Neurosci Res 2004; 77:240-9. [PMID: 15211590 DOI: 10.1002/jnr.20153] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The ligand-activated transcription factor peroxisome proliferator-activated receptor beta (PPARbeta) is present in the brain and is implicated in the regulation of genes with potential roles in neurotoxicity. We sought to examine the role of PPARbeta in neuronal cell death by using the PPARbeta ligand GW0742. Primary cultures of rat cerebellar granule neurons were prepared from 7-day-old pups. Reverse transcriptase-polymerase chain reaction and in situ hybridization were used to verify that PPARbeta mRNA was present in neurons. After 10-12 days in culture, the neuronal cells were incubated in the presence of GW0742, and cell death was measured with a lactate dehydrogenase release (LDH) assay. After 24 hr of exposure, PPARbeta activation by GW0742 was not inherently toxic to cerebellar granule neurons. However, toxicity was observed after 48 hr, with cell death mediated via an apoptotic mechanism. In an effect opposite to that observed with PPARalpha-activating ligands, PPARbeta activation exhibited neuroprotective properties. Treatment with GW0742 significantly reduced cell death during a 12-hr exposure to low-KCl media. These results clearly reinforce very specific roles for the PPAR isoforms in neurons and suggest that PPARbeta is worthy of further investigation regarding its potential role as a therapeutic target in neurodegenerative states.
Collapse
Affiliation(s)
- Steven A Smith
- School of Pharmacy, The University of Queensland, St. Lucia, Queensland, Australia
| | | | | | | | | | | |
Collapse
|
16
|
Dressel U, Allen TL, Pippal JB, Rohde PR, Lau P, Muscat GEO. The peroxisome proliferator-activated receptor beta/delta agonist, GW501516, regulates the expression of genes involved in lipid catabolism and energy uncoupling in skeletal muscle cells. Mol Endocrinol 2003; 17:2477-93. [PMID: 14525954 DOI: 10.1210/me.2003-0151] [Citation(s) in RCA: 299] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Lipid homeostasis is controlled by the peroxisome proliferator-activated receptors (PPARalpha, -beta/delta, and -gamma) that function as fatty acid-dependent DNA-binding proteins that regulate lipid metabolism. In vitro and in vivo genetic and pharmacological studies have demonstrated PPARalpha regulates lipid catabolism. In contrast, PPARgamma regulates the conflicting process of lipid storage. However, relatively little is known about PPARbeta/delta in the context of target tissues, target genes, lipid homeostasis, and functional overlap with PPARalpha and -gamma. PPARbeta/delta, a very low-density lipoprotein sensor, is abundantly expressed in skeletal muscle, a major mass peripheral tissue that accounts for approximately 40% of total body weight. Skeletal muscle is a metabolically active tissue, and a primary site of glucose metabolism, fatty acid oxidation, and cholesterol efflux. Consequently, it has a significant role in insulin sensitivity, the blood-lipid profile, and lipid homeostasis. Surprisingly, the role of PPARbeta/delta in skeletal muscle has not been investigated. We utilize selective PPARalpha, -beta/delta, -gamma, and liver X receptor agonists in skeletal muscle cells to understand the functional role of PPARbeta/delta, and the complementary and/or contrasting roles of PPARs in this major mass peripheral tissue. Activation of PPARbeta/delta by GW501516 in skeletal muscle cells induces the expression of genes involved in preferential lipid utilization, beta-oxidation, cholesterol efflux, and energy uncoupling. Furthermore, we show that treatment of muscle cells with GW501516 increases apolipoprotein-A1 specific efflux of intracellular cholesterol, thus identifying this tissue as an important target of PPARbeta/delta agonists. Interestingly, fenofibrate induces genes involved in fructose uptake, and glycogen formation. In contrast, rosiglitazone-mediated activation of PPARgamma induces gene expression associated with glucose uptake, fatty acid synthesis, and lipid storage. Furthermore, we show that the PPAR-dependent reporter in the muscle carnitine palmitoyl-transferase-1 promoter is directly regulated by PPARbeta/delta, and not PPARalpha in skeletal muscle cells in a PPARgamma coactivator-1-dependent manner. This study demonstrates that PPARs have distinct roles in skeletal muscle cells with respect to the regulation of lipid, carbohydrate, and energy homeostasis. Moreover, we surmise that PPARbeta/delta agonists would increase fatty acid catabolism, cholesterol efflux, and energy expenditure in muscle, and speculate selective activators of PPARbeta/delta may have therapeutic utility in the treatment of hyperlipidemia, atherosclerosis, and obesity.
Collapse
Affiliation(s)
- Uwe Dressel
- Institute Molecular Bioscience, St. Lucia, Queensland 4072, Australia.
| | | | | | | | | | | |
Collapse
|
17
|
Deutsch J, Rapoport SI, Rosenberger TA. Valproyl-CoA and esterified valproic acid are not found in brains of rats treated with valproic acid, but the brain concentrations of CoA and acetyl-CoA are altered. Neurochem Res 2003; 28:861-6. [PMID: 12718439 DOI: 10.1023/a:1023267224819] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Sodium valproate and lithium are used to treat bipolar disorder. In rats, both reduce the turnover of arachidonic acid in several brain phospholipids, suggesting that arachidonate turnover is a common target of action of these mood stabilizers. However, the mechanisms by which these drugs reduce arachidonate turnover in brain are not the same. Lithium decreases turnover by reducing the activity and expression of the 85-kDa type IVA cytosolic phospholipase A2 (cPLA2); valproate does not affect cPLA2 activity or expression. To test whether valproate alters neural membrane order by direct esterification into phospholipid or by interrupting intermediary CoA metabolism, we measured valproyl-CoA, esterified valproate, and short chain acyl-CoAs in brains from control rats and rats treated chronically with sodium valproate. Valproyl-CoA and esterified forms of valproate were not found in brain with detection limits of 25 and 37.5 pmol/g brain(-1), respectively. Valproate treatment did result in a 1.4-fold decrease and 1.5-fold increase in the brain concentrations of free CoA and acetyl-CoA when compared to control. Therefore the reduction of brain arachidonic acid turnover by chronic valproate in rats is not related to the formation of valproyl-CoA or esterified valproate, but may involve changes in the intermediary metabolism of CoA and short chain acyl-CoA.
Collapse
Affiliation(s)
- Joseph Deutsch
- Department of Medicinal Chemistry, David R. Bloom Center for Pharmacy, The Hebrew University School of Pharmacy, Jerusalem, Israel
| | | | | |
Collapse
|