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Maternal Inflammation Exaggerates Offspring Susceptibility to Cerebral Ischemia–Reperfusion Injury via the COX-2/PGD2/DP2 Pathway Activation. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:1571705. [PMID: 35437456 PMCID: PMC9013311 DOI: 10.1155/2022/1571705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 03/15/2022] [Accepted: 03/23/2022] [Indexed: 12/04/2022]
Abstract
The pathogenesis of cerebral ischemia–reperfusion (I/R) injury is complex and does not exhibit an effective strategy. Maternal inflammation represents one of the most important factors involved in the etiology of brain injury in newborns. We aimed to investigate the effect of maternal inflammation on offspring susceptibility to cerebral I/R injury and the mechanisms by which it exerts its effects. Pregnant SD rats were intraperitoneally injected with LPS (300 μg/kg/day) at gestational days 11, 14, and 18. Pups were subjected to MCAO/R on postnatal day 60. Primary neurons were obtained from postnatal day 0 SD rats and subjected to OGD/R. Neurological deficits, brain injury, neuronal viability, neuronal damage, and neuronal apoptosis were assessed. Oxidative stress and inflammation were evaluated, and the expression levels of COX-2/PGD2/DP pathway-related proteins and apoptotic proteins were detected. Maternal LPS exposure significantly increased the levels of oxidative stress and inflammation, significantly activated the COX-2/PGD2/DP2 pathway, and increased proapoptotic protein expression. However, maternal LPS exposure significantly decreased the antiapoptotic protein expression, which subsequently increased neurological deficits and cerebral I/R injury in offspring rats. The corresponding results were observed in primary neurons. Moreover, these effects of maternal LPS exposure were reversed by a COX-2 inhibitor and DP1 agonist but exacerbated by a DP2 agonist. In conclusion, maternal inflammatory exposure may increase offspring susceptibility to cerebral I/R injury. Moreover, the underlying mechanism might be related to the activation of the COX-2/PGD2/DP2 pathway. These findings provide a theoretical foundation for the development of therapeutic drugs for cerebral I/R injury.
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Abstract
Chiglitazar (Bilessglu®) is an orally administered, non-thiazolidinedione small-molecule agonist of α, δ and γ peroxisome proliferator-activated receptors (PPARs) being developed by Chipscreen Biosciences for the treatment of type 2 diabetes (T2D) and non-alcoholic steatohepatitis. In October 2021, chiglitazar was approved in China for use as an adjunct to diet and exercise to improve glycaemic control in adult patients with T2D. The drug is also in phase 2 clinical development in China for the treatment of non-alcoholic steatohepatitis. This article summarizes the milestones in the development of chiglitazar leading to this first approval for the treatment of T2D.
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Murillo-Rodríguez E, Arankowsky-Sandoval G, Budde H, Imperatori C, Machado S, Yamamoto T, Yadollahpour A, Torterolo P. In vivo brain levels of acetylcholine and 5-hydroxytryptamine after oleoylethanolamide or palmitoylethanolamide administrations are mediated by PPARα engagement. Eur J Neurosci 2021; 54:5932-5950. [PMID: 34396611 DOI: 10.1111/ejn.15409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/06/2021] [Accepted: 07/25/2021] [Indexed: 11/29/2022]
Abstract
The peroxisome proliferator-activated receptor alpha (PPARα) is a nuclear receptor that has been linked to the modulation of several physiological functions, including the sleep-wake cycle. The PPARα recognizes as endogenous ligands the lipids oleoylethanolamide (OEA) and palmitoylethanolamide (PEA), which in turn, if systemically injected, they exert wake-promoting effects. Moreover, the activation of PPARα by the administration of OEA or PEA increases the extracellular contents of neurotransmitters linked to the control of wakefulness; however, the role of PPARα activated by OEA or PEA on additional biochemicals related to waking regulation, such as acetylcholine (ACh) and 5-hydroxytryptamine (5-HT), has not been fully studied. Here, we have investigated the effects of treatments of OEA or PEA on the contents of ACh and 5-HT by using in vivo microdialysis techniques coupled to HPLC means. For this purpose, OEA or PEA were systemically injected (5, 10 or 30 mg/kg; i.p.), and the levels of ACh and 5-HT were collected from the basal forebrain, a wake-related brain area. These pharmacological treatments significantly increased the contents of ACh and 5-HT as determined by HPLC procedures. Interestingly, PPARα antagonist MK-886 (30 mg/kg; i.p.) injected before the treatments of OEA or PEA blocked these outcomes. Our data suggest that the activation of PPARα by OEA or PEA produces significant changes on ACh and 5-HT levels measured from the basal forebrain and support the conclusion that PPARα is a suitable molecular element involved in the regulation of wake-related neurotransmitters.
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Affiliation(s)
- Eric Murillo-Rodríguez
- Laboratorio de Neurociencias Moleculares e Integrativas, Escuela de Medicina, División Ciencias de la Salud, Universidad Anáhuac Mayab, Mérida, Yucatán, Mexico.,Intercontinental Neuroscience Research Group
| | - Gloria Arankowsky-Sandoval
- Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
| | - Henning Budde
- Intercontinental Neuroscience Research Group.,Institute for Systems Medicine, Faculty of Human Sciences, MSH Medical School Hamburg, Hamburg, Germany
| | - Claudio Imperatori
- Intercontinental Neuroscience Research Group.,Cognitive and Clinical Psychology Laboratory, Department of Human Science, European University of Rome, Rome, Italy
| | - Sérgio Machado
- Intercontinental Neuroscience Research Group.,Department of Sports Methods and Techniques, Federal University of Santa Maria, Santa Maria, Brazil.,Laboratory of Physical Activity Neuroscience, Neurodiversity Institute, Queimados, Brazil
| | - Tetsuya Yamamoto
- Intercontinental Neuroscience Research Group.,Graduate School of Technology, Industrial and Social Sciences, Tokushima University, Tokushima, Japan
| | - Ali Yadollahpour
- Intercontinental Neuroscience Research Group.,Department of Psychology, University of Sheffield, Sheffield, UK
| | - Pablo Torterolo
- Intercontinental Neuroscience Research Group.,Laboratorio de Neurobiología del Sueño, Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
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Hanlon C, Ramachandran R, Zuidhof MJ, Bédécarrats GY. Should I Lay or Should I Grow: Photoperiodic Versus Metabolic Cues in Chickens. Front Physiol 2020; 11:707. [PMID: 32670092 PMCID: PMC7332832 DOI: 10.3389/fphys.2020.00707] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 05/29/2020] [Indexed: 12/11/2022] Open
Abstract
While photoperiod has been generally accepted as the primary if not the exclusive cue to stimulate reproduction in photoperiodic breeders such as the laying hen, current knowledge suggests that metabolism, and/or body composition can also play an influential role to control the hypothalamic-pituitary gonadal (HPG)-axis. This review thus intends to first describe how photoperiodic and metabolic cues can impact the HPG axis, then explore and propose potential common pathways and mechanisms through which both cues could be integrated. Photostimulation refers to a perceived increase in day-length resulting in the stimulation of the HPG. While photoreceptors are present in the retina of the eye and the pineal gland, it is the deep brain photoreceptors (DBPs) located in the hypothalamus that have been identified as the potential mediators of photostimulation, including melanopsin (OPN4), neuropsin (OPN5), and vertebrate-ancient opsin (VA-Opsin). Here, we present the current state of knowledge surrounding these DBPs, along with their individual and relative importance and, their possible downstream mechanisms of action to initiate the activation of the HPG axis. On the metabolic side, specific attention is placed on the hypothalamic integration of appetite control with the stimulatory (Gonadotropin Releasing Hormone; GnRH) and inhibitory (Gonadotropin Inhibitory Hormone; GnIH) neuropeptides involved in the control of the HPG axis. Specifically, the impact of orexigenic peptides agouti-related peptide (AgRP), and neuropeptide Y (NPY), as well as the anorexigenic peptides pro-opiomelanocortin (POMC), and cocaine-and amphetamine regulated transcript (CART) is reviewed. Furthermore, beyond hypothalamic control, several metabolic factors involved in the control of body weight and composition are also presented as possible modulators of reproduction at all three levels of the HPG axis. These include peroxisome proliferator-activated receptor gamma (PPAR-γ) for its impact in liver metabolism during the switch from growth to reproduction, adiponectin as a potential modulator of ovarian development and follicular maturation, as well as growth hormone (GH), and leptin (LEP).
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Affiliation(s)
- Charlene Hanlon
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
| | - Ramesh Ramachandran
- Center for Reproductive Biology and Health, Department of Animal Science, Pennsylvania State University, University Park, PA, United States
| | - Martin J. Zuidhof
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
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Peroxisome proliferator-activated receptor gamma (PPARγ), a key regulatory gene of lipid metabolism in chicken. WORLD POULTRY SCI J 2019. [DOI: 10.1017/s0043933916000684] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Simeone TA, Matthews SA, Samson KK, Simeone KA. Regulation of brain PPARgamma2 contributes to ketogenic diet anti-seizure efficacy. Exp Neurol 2016; 287:54-64. [PMID: 27527983 DOI: 10.1016/j.expneurol.2016.08.006] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 08/05/2016] [Accepted: 08/11/2016] [Indexed: 12/23/2022]
Abstract
The ketogenic diet (KD) is an effective therapy primarily used in pediatric patients whom are refractory to current anti-seizure medications. The mechanism of the KD is not completely understood, but is thought to involve anti-inflammatory and anti-oxidant processes. The nutritionally-regulated transcription factor peroxisome proliferator activated receptor gamma, PPARγ, regulates genes involved in anti-inflammatory and anti-oxidant pathways. Moreover, endogenous ligands of PPARγ include fatty acids suggesting a potential role in the effects of the KD. Here, we tested the hypothesis that PPARγ contributes to the anti-seizure efficacy of the KD. We found that the KD increased nuclear protein content of the PPARγ2 splice variant by 2-4 fold (P<0.05) in brain homogenates from wild-type (WT) and epileptic Kv1.1 knockout (KO) mice, while not affecting PPARγ1. The KD reduced the frequency of seizures in Kv1.1KO mice by ~70% (P<0.01). GW9662, a PPARγ antagonist, prevented KD-mediated changes in PPARγ2 expression and prevented the anti-seizure efficacy of the KD in Kv1.1KO mice. Further supporting the association of PPARγ2 in mediating KD actions, the KD significantly prolonged the latency to flurothyl-induced seizure in WT mice by ~20-35% (P<0.01), but was ineffective in PPARγ2KO mice and neuron-specific PPARγKO mice. Finally, administering the PPARγ agonist pioglitazone increased PPARγ2 expression by 2-fold (P<0.01) and reduced seizures in Kv1.1KO mice by ~80% (P<0.01). Our findings implicate brain PPARγ2 among the mechanisms by which the KD reduces seizures and strongly support the development of PPARγ2 as a therapeutic target for severe, refractory epilepsy.
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Affiliation(s)
- Timothy A Simeone
- Creighton University, School of Medicine, Department of Pharmacology, Omaha, NE 68174, USA.
| | - Stephanie A Matthews
- Creighton University, School of Medicine, Department of Pharmacology, Omaha, NE 68174, USA
| | - Kaeli K Samson
- Creighton University, School of Medicine, Department of Pharmacology, Omaha, NE 68174, USA
| | - Kristina A Simeone
- Creighton University, School of Medicine, Department of Pharmacology, Omaha, NE 68174, USA
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Liang G, Shi B, Luo W, Yang J. The protective effect of caffeic acid on global cerebral ischemia-reperfusion injury in rats. Behav Brain Funct 2015; 11:18. [PMID: 25907417 PMCID: PMC4407787 DOI: 10.1186/s12993-015-0064-x] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 04/14/2015] [Indexed: 12/29/2022] Open
Abstract
Ischemic stroke is a major cause of death and disability all over the world. Ischemic stroke results from a temporary or permanent reduction of cerebral blood flow that leads to functional and structural damage in different brain regions. Despite decades of intense research, the beneficial treatment of stroke remains limited. In light of this, the search for effective means ameliorating cerebral ischemia-reperfusion injury (CIRI) is one of the major problems of experimental medicine and biology. Recently, the 5-Lipoxygenase (5-LO, a key enzyme metabolizing arachidonic acid to produce leukotrienes) inhibitors have been showed to protect brain against ischemic damage in animal model of cerebral ischemia. Caffeic acid, an inhibitor of 5-LO, is a phenolic compound widely distributed in medicinal plants. The aim of this study was to investigate the effect of caffeic acid on global cerebral ischemia-reperfusion injury in rats. The study was carried out on 45 rats that were randomly divided into five groups: the sham group (n = 9), I/R non-treated group (n = 9), I/R-caffeic acid group (10 mg · kg−1) (n = 9), I/R-caffeic acid group (30 mg · kg−1) (n = 9) and I/R-caffeic acid group (50 mg · kg−1) (n = 9). Global cerebral ischemia was induced by bilateral carotid artery occlusion for 20 min followed by reperfusion. Spatial learning and memory was evaluated using Morris water maze. Histopathological changes of hippocampus neurons was observed using HE staining. Superoxide dismutase (SOD, the antioxidant enzyme) activities and malondialdehyde (MDA, an oxidative stress biomarker) contents were detected. NF-κBp65 expression was detected by the methods of immunohistochemistry. Caffeic acid markedly reduced the escape latency, relieved hippocampal neurons injury and increased neuron count compared with those of I/R non-treated rat. NF-κBp65 expression and MDA content decreased significantly, and SOD activities increased significantly in hippocampus. Compared with sham group, 5-LO expression increase significantly in I/R non-treated group rat, and caffeic acid markedly reduced 5-LO expression. The results of the study suggest that caffeic acid has a significant protective effect on global cerebral ischemia-reperfusion injury in rats. The neuroprotective effects is likely to be mediated through the inhibition of 5-LO.
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Affiliation(s)
- Guojuan Liang
- Department of Pharmacology, Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing Medical University, Medical College Rd. No 1, Chongqing, 400016, P. R. China.
| | - Bin Shi
- Department of Pharmacology, Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing Medical University, Medical College Rd. No 1, Chongqing, 400016, P. R. China.
| | - Weinan Luo
- Department of Pharmacology, Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing Medical University, Medical College Rd. No 1, Chongqing, 400016, P. R. China.
| | - Junqing Yang
- Department of Pharmacology, Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing Medical University, Medical College Rd. No 1, Chongqing, 400016, P. R. China.
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Wang H, Ye M, Yu L, Wang J, Guo Y, Lei W, Yang J. Hippocampal neuronal cyclooxygenase-2 downstream signaling imbalance in a rat model of chronic aluminium gluconate administration. Behav Brain Funct 2015; 11:8. [PMID: 25888969 PMCID: PMC4336726 DOI: 10.1186/s12993-015-0054-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Accepted: 01/21/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Acute and chronic brain damages including neurodegenerative diseases are a group of neuroinflammation-associated diseases characterized by cognitive function defect and progressive neuron loss. The pathophysiological procession of brain damages involves the overexpression of cyclooxygenase (COX)-2. Owing to the limited benefit to chronic brain damage and the late adverse effect of COX-2 inhibitors, the COX downstream signaling pathway has become a focus in neurological research. In order to explore the mechanism of aluminum neurotoxicity and the importance of COX2 downstream signaling pathways to chronic brain damage, the present study was designed to simultaneously observe the prostaglandin (PG) contents, and the expressions of PG synthases and PG receptors of hippocampus in a rat model induced by chronic administration of aluminium gluconate. METHODS A rat model of chronic brain damage was established by chronic intragastric administration of aluminium gluconate (Al3+ 200 mg/kg per day, 5d a week for 20 weeks). PG contents, the expressions of PG synthases, and the expressions of PG receptors in rats were measured by ELISA, RT-PCR and Western blotting, respectively. RESULTS Chronic aluminium gluconate administration resulted in hippocampal neuron injury and learning and memory disorders in rats. Aluminium gluconate administration also resulted in increased levels of PGE2, PGD2, TXA2, PGI2, and PGF2α in rat hippocampus. The DP1, EP2, IP, mPGES-1, EP4, PGIS and TXAS mRNA expressions, and the DP1, EP2 and IP protein expressions significantly increased in the Al-treated hippocampus, while the EP3 and FP mRNA and protein expressions and the TP mRNA expression decreased. CONCLUSIONS The PGS/PGs/PG receptors signaling pathway in chronic aluminium gluconate-overloaded rat hippocampus is disturbed, which may be involved in the mechanism of aluminium neurotoxicity.
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Affiliation(s)
- Hong Wang
- Department of Pharmacology, Chongqing Medical University, Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing, 400016, China.
| | - Mengliang Ye
- Department of Biostatistics, School of Public Health, Chongqing Medical University, Chongqing, Chongqing, 400016, China.
| | - Lijuan Yu
- Department of Pharmacology, Chongqing Medical University, Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing, 400016, China.
| | - Jianfeng Wang
- Department of Pharmacology, Chongqing Medical University, Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing, 400016, China.
| | - Yuanxin Guo
- Department of Pharmacology, Chongqing Medical University, Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing, 400016, China.
| | - Wenjuan Lei
- Department of Pharmacology, Chongqing Medical University, Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing, 400016, China.
| | - Junqing Yang
- Department of Pharmacology, Chongqing Medical University, Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing, 400016, China.
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Yu L, Yang B, Wang J, Zhao L, Luo W, Jiang Q, Yang J. Time course change of COX2-PGI2/TXA2 following global cerebral ischemia reperfusion injury in rat hippocampus. Behav Brain Funct 2014; 10:42. [PMID: 25388440 PMCID: PMC4240876 DOI: 10.1186/1744-9081-10-42] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Accepted: 10/22/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Neuroinflammation plays pivotal roles in the progression of cerebral ischemia injury. Prostaglandins (PGs) as the major inflammatory mediators in the brain participate in the pathophysiological processes of cerebral ischemia injury. Cyclooxygenase-2 (COX2) is the rate-limiting enzyme of PGs, and thus it is necessary to characterize of the expression patterns of COX2 and its downstream products at the same time in a cerebral ischemia/reperfusion (I/R) model. METHODS The levels of prostacyclin (PGI2) and thromboxane (TXA2) and the expression of COX2 were detected in the rat hippocampus at different time points after reperfusion (30 min, 2 h, 6 h, 24 h, 48 h, 7 d, and 15 d). RESULTS The COX2 mRNA and protein expressions in hippocampus both remarkably increased at 30 min, and peaked at 7 d after global cerebral I/R compared with the sham-operated group. The level of PGI2 significantly increased at 2 h after reperfusion, with a peak at 48 h, but was still significantly higher than the sham-operated animals at 15 d. TXA2 level decreased at 30 min and 2 h after reperfusion, but significantly increased at 6 h and peaked at 48 h. PGI2/TXA2 ratio increased at 30 min after reperfusion, and peaked at 48 h compared with the sham-operated animals. CONCLUSIONS I/R injury significantly increased the COX2 expression, PGI2 and TXA2 levels, and the PGI2/TXA2 ratio in rat hippocampus in a time-dependent manner. As a consequence, the increased PGI2 level and PGI2/TXA2 ratio may represent a physiological mechanism to protect the brain against the neuronal damage produced by I/R injury.
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Affiliation(s)
| | | | | | | | | | | | - Junqing Yang
- Department of Pharmacology, Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing Medical University, Medical College Rd, No 1, Chongqing 400016, China.
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Freitag CM, Miller RJ. Peroxisome proliferator-activated receptor agonists modulate neuropathic pain: a link to chemokines? Front Cell Neurosci 2014; 8:238. [PMID: 25191225 PMCID: PMC4138931 DOI: 10.3389/fncel.2014.00238] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 07/28/2014] [Indexed: 11/29/2022] Open
Abstract
Chronic pain presents a widespread and intractable medical problem. While numerous pharmaceuticals are used to treat chronic pain, drugs that are safe for extended use and highly effective at treating the most severe pain do not yet exist. Chronic pain resulting from nervous system injury (neuropathic pain) is common in conditions ranging from multiple sclerosis to HIV-1 infection to type II diabetes. Inflammation caused by neuropathy is believed to contribute to the generation and maintenance of neuropathic pain. Chemokines are key inflammatory mediators, several of which (MCP-1, RANTES, MIP-1α, fractalkine, SDF-1 among others) have been linked to chronic, neuropathic pain in both human conditions and animal models. The important roles chemokines play in inflammation and pain make them an attractive therapeutic target. Peroxisome proliferator-activated receptors (PPARs) are a family of nuclear receptors known for their roles in metabolism. Recent research has revealed that PPARs also play a role in inflammatory gene repression. PPAR agonists have wide-ranging effects including inhibition of chemokine expression and pain behavior reduction in animal models. Experimental evidence suggests a connection between the pain ameliorating effects of PPAR agonists and suppression of inflammatory gene expression, including chemokines. In early clinical research, one PPARα agonist, palmitoylethanolamide (PEA), shows promise in relieving chronic pain. If this link can be better established, PPAR agonists may represent a new drug therapy for neuropathic pain.
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Affiliation(s)
- Caroline M Freitag
- Department of Molecular Pharmacology and Biological Chemistry, Richard J. Miller Laboratory, Northwestern University Chicago, IL, USA
| | - Richard J Miller
- Department of Molecular Pharmacology and Biological Chemistry, Richard J. Miller Laboratory, Northwestern University Chicago, IL, USA
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Lee CH, Won MH. Change of peroxisome proliferator-activated receptor γ expression pattern in the gerbil dentate gyrus after transient global cerebral ischemia. Anat Cell Biol 2014; 47:111-6. [PMID: 24987547 PMCID: PMC4076417 DOI: 10.5115/acb.2014.47.2.111] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 04/03/2014] [Accepted: 04/28/2014] [Indexed: 12/03/2022] Open
Abstract
Peroxisome proliferator-activated receptor γ (PPARγ) has various actions including the regulation of adipocyte differentiation, lipid metabolism and glucose homeostasis. In the present study, we examined the changes of PPARγ immunoreactivity and protein levels in the gerbil dentate gyrus (DG) after transient global cerebral ischemia using immunohistochemistry and western blot analysis. PPARγ immunoreactivity was gradually increased from 1 day after ischemia-reperfusion. PPARγ immunoreactivity, in accordance with protein level, was highest at 2 days after ischemia-reperfusion and was detected in microglia at this time. Thereafter, both PPARγ immunoreactivity and protein level were decreased with time in the ischemic DG. These results indicate that PPARγ may be related to the ischemia-induced microglial activation and neuronal damage/death in the DG after transient global cerebral ischemia.
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Affiliation(s)
- Choong Hyun Lee
- Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan, Korea
| | - Moo-Ho Won
- Department of Neurobiology and Institute of Medical Sciences, Kangwon National University School of Medicine, Chuncheon, Korea
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Luo Y, He Q, Kuang G, Jiang Q, Yang J. PPAR-alpha and PPAR-beta expression changes in the hippocampus of rats undergoing global cerebral ischemia/reperfusion due to PPAR-gamma status. Behav Brain Funct 2014; 10:21. [PMID: 24934302 PMCID: PMC4167308 DOI: 10.1186/1744-9081-10-21] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 06/08/2014] [Indexed: 12/19/2022] Open
Abstract
Background Peroxisome proliferator-activated receptors (PPARs, including alpha, beta and gamma subtypes) and their agonists have a protective role in treatment of central nervous system (CNS) diseases. The present study was designed to investigate the expression changes of PPAR-alpha, -beta, -gamma and NF-kappa B in the hippocampus of rats with global cerebral ischemia/reperfusion injury (GCIRI) after treatment with agonists or antagonists of PPAR-gamma. Methods A rat GCIRI model was established by occlusion of bilateral common carotid arteries and cervical vena retransfusion. GW9662 (5 μg), a selective PPAR- gamma antagonist, was intraventricularly injected at 0.5 h before GCIR; Rosiglitazone (0.8, 2.4 and 7.2 mg/kg), a selective PPAR- gamma agonist, was injected intraperitoneally at 1 h before GCIRI. The expression changes of PPAR-alpha, -beta and -gamma at mRNA and protein levels were detected by RT-PCR and western blotting. The changes of spatial learning and memory (SLM) functions were assessed by using a Morris water maze; the pathohistological changes of hippocampal neurons were evaluated by hematoxylin-eosin (HE) staining; the contents of IL-1, IL-6, IL-10 and TNF-alpha, and the NF- kappa B expression were measured by enzyme-linked immunosorbent assay (ELISA) and immunohistochemical staining. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were also detected. Results The SLM function and hippocampal neurons were significantly impaired after the occurrence of GCIRI. The MDA, IL-1, IL-6, IL-10, TNF-alpha content and expression of PPARs increased significantly, but the SOD activity and NF-kappa B expression were weakened in the hippocampus. Rosiglitazone treatment significantly protected rats from SLM function impairment and neuron death, and resulted in higher expressions of SOD activity and NF-kappa B, but lower contents of MDA and inflammatory factors. After treatment with rosiglitazone or GW9662, no significant change in PPAR-alpha or -beta expression was detected. Conclusions Rosiglitazone, a PPAR-gamma agonist, plays a protective role in hippocampal neuron damage of GCIRI rats by inhibiting the oxidative stress response and inflammation. The activation or antagonism of PPAR-gamma did not affect the expression of PPAR-alpha or -beta, indicating that the three subtypes of PPARs act in independent pathways in the CNS.
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Affiliation(s)
| | | | | | | | - Junqing Yang
- Department of Pharmacology, Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing Medical University, Medical College Rd, No 1, Chongqing 400016, P, R, China.
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Singh M, Padhy G, Vats P, Bhargava K, Sethy NK. Hypobaric hypoxia induced arginase expression limits nitric oxide availability and signaling in rodent heart. Biochim Biophys Acta Gen Subj 2014; 1840:1817-24. [PMID: 24440670 DOI: 10.1016/j.bbagen.2014.01.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 01/08/2014] [Accepted: 01/09/2014] [Indexed: 11/25/2022]
Abstract
BACKGROUND This study was aimed to evaluate regulation of cardiac arginase expression during hypobaric hypoxia and subsequent effect on nitric oxide availability and signaling. METHODS Rats were exposed to hypobaric hypoxia (282mmHg for 3h) and ARG1 expression was monitored. The expression levels of eNOS and eNOS(Ser1177) were determined by Western blotting, cGMP levels were measured by ELISA and amino acid concentrations were measured by HPLC analysis. Transcription regulation of arginase was monitored by chromatin immunoprecipitation (ChIP) assay with anti-c-Jun antibody for AP-1 consensus binding site on ARG1 promoter. Arginase activity was inhibited by intra-venous dose of N-(ω)-hydroxy-nor-l-arginine (nor-NOHA) prior to hypoxia exposure and subsequent effect on NO availability and oxidative stress were evaluated. RESULTS Hypobaric hypoxia induced cardiac arginase expression by recruiting c-Jun to AP-1 binding site on ARG1 promoter. This increased expression redirected l-arginine towards arginase and resulted in limited endothelial nitric oxide synthase (eNOS) activity, nitric oxide (NO) availability and cGMP mediated signaling. Inhibition of arginase restored the eNOS activity, promoted cardiac NO availability and ameliorated peroxynitrite formation during hypoxia. CONCLUSIONS Hypoxic induced arginase under transcription control of AP-1 reciprocally regulates eNOS activity and NO availability in the heart. This also results in cardiac oxidative stress. GENERAL SIGNIFICANCE This study provides understanding of hypoxia-mediated transcriptional regulation of arginase expression in the heart and its subsequent effect on eNOS activity, NO availability and signaling as well as cardiac oxidative stress. This information will support the use of arginase inhibitors as therapeutics for pathological hypoxia.
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Affiliation(s)
- Manjulata Singh
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organisation, Lucknow Road, Timarpur, Delhi 110054, India
| | - Gayatri Padhy
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organisation, Lucknow Road, Timarpur, Delhi 110054, India
| | - Praveen Vats
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organisation, Lucknow Road, Timarpur, Delhi 110054, India
| | - Kalpana Bhargava
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organisation, Lucknow Road, Timarpur, Delhi 110054, India.
| | - Niroj Kumar Sethy
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organisation, Lucknow Road, Timarpur, Delhi 110054, India.
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