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The Anti-Edematous Effect of Ghrelin in Brain Hypoxia is Associated with Decreasing Expression of Vascular Endothelial Growth Factor. J Mol Neurosci 2015; 56:273-7. [DOI: 10.1007/s12031-015-0528-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 02/16/2015] [Indexed: 01/21/2023]
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Hu N, Wu Y, Chen BZ, Han JF, Zhou MT. Protective effect of stellate ganglion block on delayed cerebral vasospasm in an experimental rat model of subarachnoid hemorrhage. Brain Res 2014; 1585:63-71. [DOI: 10.1016/j.brainres.2014.08.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 02/27/2014] [Accepted: 08/07/2014] [Indexed: 11/26/2022]
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Hao XK, Wu W, Wang CX, Xie GB, Li T, Wu HM, Huang LT, Zhou ML, Hang CH, Shi JX. Ghrelin alleviates early brain injury after subarachnoid hemorrhage via the PI3K/Akt signaling pathway. Brain Res 2014; 1587:15-22. [PMID: 25199591 DOI: 10.1016/j.brainres.2014.08.069] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 08/25/2014] [Accepted: 08/29/2014] [Indexed: 12/25/2022]
Abstract
Early brain injury (EBI) plays a key role in the pathogenesis of subarachnoid hemorrhage (SAH). Although the neuroprotective effects of ghrelin have been demonstrated in several studies, whether ghrelin reduces EBI after SAH remains unknown. In this study, we hypothesized that treatment with ghrelin would attenuate EBI after SAH, and that this protection would be mediated, at least in part, by activation of the PI3K/Akt signaling pathway. Adult male Sprague-Dawley rats (n=100) were randomly divided into the following groups: control group (n=20), SAH group (n=20), SAH+vehicle group (n=20), SAH+ghrelin group (n=20) and SAH+ghrelin+LY294002 group (n=20). The rats were injected with autologous blood (0.3mL) into the prechiasmatic cistern to induce SAH. Ghrelin (80μg/kg, IP), or an equal volume of vehicle, was administered immediately after surgery. The PI3K inhibitor, LY294002, was applied to manipulate the proposed pathway. Mortality, neurological scores, brain edema, cell apoptosis, and the expression of p-Akt, and cleaved caspase-3 proteins were assayed after 24h SAH. Ghrelin significantly improved neurological function and reduced neuronal apoptosis and brain edema at 24h after SAH. The level of p-Akt, expressed mainly in neurons, was markedly up-regulated. Additionally, the level of cleaved caspase-3 was decreased by ghrelin treatment. The beneficial effects of ghrelin in SAH rats were partially suppressed by LY294002. These results demonstrate that ghrelin may reduce EBI after SAH, via a mechanism involving the PI3K/Akt signaling pathway.
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Affiliation(s)
- Xiao-Ke Hao
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Second Military Medical University, Shanghai, China
| | - Wei Wu
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Second Military Medical University, Shanghai, China; Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Chun-Xi Wang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Guang-Bin Xie
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Tao Li
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - He-Ming Wu
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Second Military Medical University, Shanghai, China
| | - Li-Tian Huang
- Department of Neurosurgery, School of Medicine, Southern Medical University (Guangzhou), Jinling Hospital, Nanjing, Jiangsu Province, China
| | - Meng-Liang Zhou
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Chun-Hua Hang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Second Military Medical University, Shanghai, China; Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Ji-Xin Shi
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Second Military Medical University, Shanghai, China; Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
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Abstract
Subarachnoid hemorrhage (SAH), predominantly caused by a ruptured aneurysm, is a devastating neurological disease that has a morbidity and mortality rate higher than 50%. Most of the traditional in vivo research has focused on the pathophysiological or morphological changes of large-arteries after intracisternal blood injection. This was due to a widely held assumption that delayed vasospasm following SAH was the major cause of delayed cerebral ischemia and poor outcome. However, the results of the CONSCIOUS-1 trial implicated some other pathophysiological factors, independent of angiographic vasospasm, in contributing to the poor clinical outcome. The term early brain injury (EBI) has been coined and describes the immediate injury to the brain after SAH, before onset of delayed vasospasm. During the EBI period, a ruptured aneurysm brings on many physiological derangements such as increasing intracranial pressure (ICP), decreased cerebral blood flow (CBF), and global cerebral ischemia. These events initiate secondary injuries such as blood-brain barrier disruption, inflammation, and oxidative cascades that all ultimately lead to cell death. Given the fact that the reversal of vasospasm does not appear to improve patient outcome, it could be argued that the treatment of EBI may successfully attenuate some of the devastating secondary injuries and improve the outcome of patients with SAH. In this review, we provide an overview of the major advances in EBI after SAH research.
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Catak Z, Aydin S, Sahin I, Kuloglu T, Aksoy A, Dagli AF. Regulatory neuropeptides (ghrelin, obestatin and nesfatin-1) levels in serum and reproductive tissues of female and male rats with fructose-induced metabolic syndrome. Neuropeptides 2014; 48:167-77. [PMID: 24786976 DOI: 10.1016/j.npep.2014.04.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 04/02/2014] [Accepted: 04/07/2014] [Indexed: 12/15/2022]
Abstract
Although, the exact mechanisms underlying the development of the metabolic syndrome (MetS) are not still completely understood, obesity, circulated peptide hormone levels and their interaction with genetic factors are considered largely responsible. The purpose of this study is to explore how the levels of ghrelin, obestatin (OBS) and NUCB2/nesfatin-1 (NES)/NUCB2 change in serum and the reproductive tissues of female and male rats with fructose-induced metabolic syndrome, and whether the levels of each hormone is correlated with the hormones involved with fertility. Experiments were conducted on 5-week-old Sprague-Dawley male and female rats assigned to either a control group or a MetS group. Controls were fed standard rat food and water ad libitum, while the MetS group was fed standard food with 10% (v/v) fructose solution added to their drinking water for 12 weeks with a 12/12h photoperiod circle. Then, all animals were sacrificed after a one night fast. Peptides levels in the serum and reproductive tissues of rats were studied using the ELISA method while the immunoreactivity of reproductive system peptide hormones were shown by immunohistochemical staining method. Furthermore, the other biochemical parameters were measured using Konelab-60 equipment and infertility hormones were measured with Immulite2000. Fasting serum insulin, glucose, triglyceride, alanine aminotransferase (ALT), gamma glutamyl transpeptidase (GGT), low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC) levels were statistically significantly higher, and the amount of high density lipoprotein cholesterol (HDL-C) was significantly lower, in the MetS groups. Serum and tissue supernatant NES levels were significantly higher in the rats with MetS than the control group. Ghrelin, OBS and NES were expressed in the cytoplasm, concentrated around the apical parts of the epithelial cells in the reproductive tissues of the rats. The amounts of ghrelin were lower in the reproductive tissues of the animals with MetS, while NES levels in the same tissues increased. Obestatin also decreased, though not in the seminal glands.
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Affiliation(s)
- Zekiye Catak
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey
| | - Suleyman Aydin
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey.
| | - Ibrahim Sahin
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey; Department of Histology and Embryology, Medical School, Erzincan University, 24030 Erzincan, Turkey
| | - Tuncay Kuloglu
- Department of Histology and Embryology, Medical School, Firat University, 23119 Elazig, Turkey
| | - Aziz Aksoy
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey; Department of Nutrition and Dietetics, Bitlis Eren University, 13000 Bitlis, Turkey
| | - Adile Ferda Dagli
- Department of Medical Pathology, Medical School, Inonu University, 44280 Malatya, Turkey
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Sim YB, Park SH, Kim SS, Kim CH, Kim SJ, Lim SM, Jung JS, Suh HW. Ghrelin administered spinally increases the blood glucose level in mice. Peptides 2014; 54:162-5. [PMID: 24472858 DOI: 10.1016/j.peptides.2014.01.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/17/2014] [Accepted: 01/17/2014] [Indexed: 02/07/2023]
Abstract
Ghrelin is known as a regulator of the blood glucose homeostasis and food intake. In the present study, the possible roles of ghrelin located in the spinal cord in the regulation of the blood glucose level were investigated in ICR mice. We found that intrathecal (i.t.) injection with ghrelin (from 1 to 10 μg) caused an elevation of the blood glucose level. In addition, i.t. pretreatment with YIL781 (ghrelin receptor antagonist; from 0.1 to 5 μg) markedly attenuated ghrelin-induced hyperglycemic effect. The plasma insulin level was increased by ghrelin. The enhanced plasma insulin level by ghrelin was reduced by i.t. pretreatment with YIL781. However, i.t. pretreatment with glucagon-like peptide-1 (GLP-1; 5 μg) did not affect the ghrelin-induced hyperglycemia. Furthermore, i.t. administration with ghrelin also elevated the blood glucose level, but in an additive manner, in d-glucose-fed model. Our results suggest that the activation of ghrelin receptors located in the spinal cord plays important roles for the elevation of the blood glucose level.
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Affiliation(s)
- Yun-Beom Sim
- Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 39 Hallymdaehak-gil, Chuncheon, Gangwon-do 200-702, Republic of Korea
| | - Soo-Hyun Park
- Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 39 Hallymdaehak-gil, Chuncheon, Gangwon-do 200-702, Republic of Korea
| | - Sung-Su Kim
- Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 39 Hallymdaehak-gil, Chuncheon, Gangwon-do 200-702, Republic of Korea
| | - Chea-Ha Kim
- Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 39 Hallymdaehak-gil, Chuncheon, Gangwon-do 200-702, Republic of Korea
| | - Su-Jin Kim
- Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 39 Hallymdaehak-gil, Chuncheon, Gangwon-do 200-702, Republic of Korea
| | - Su-Min Lim
- Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 39 Hallymdaehak-gil, Chuncheon, Gangwon-do 200-702, Republic of Korea
| | - Jun-Sub Jung
- Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 39 Hallymdaehak-gil, Chuncheon, Gangwon-do 200-702, Republic of Korea
| | - Hong-Won Suh
- Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 39 Hallymdaehak-gil, Chuncheon, Gangwon-do 200-702, Republic of Korea.
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Ghrelin decreases motor deficits after traumatic brain injury. J Surg Res 2014; 187:230-236. [DOI: 10.1016/j.jss.2013.09.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 09/16/2013] [Accepted: 09/20/2013] [Indexed: 11/18/2022]
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Uekawa K, Hasegawa Y, Ma M, Nakagawa T, Katayama T, Sueta D, Toyama K, Kataoka K, Koibuchi N, Kawano T, Kuratsu JI, Kim-Mitsuyama S. Rosuvastatin ameliorates early brain injury after subarachnoid hemorrhage via suppression of superoxide formation and nuclear factor-kappa B activation in rats. J Stroke Cerebrovasc Dis 2014; 23:1429-39. [PMID: 24529602 DOI: 10.1016/j.jstrokecerebrovasdis.2013.12.004] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Revised: 10/29/2013] [Accepted: 12/03/2013] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Statins, or 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors, have been suggested to possess pleiotropic effects, including antioxidant and anti-inflammatory properties. We investigated the protective effects of pretreatment with rosuvastatin, a relatively hydrophilic statin, on early brain injury (EBI) after a subarachnoid hemorrhage (SAH), using the endovascular perforation SAH model. METHODS Eighty-six male Sprague-Dawley rats were randomly divided into 3 groups: (1) sham operation, (2) SAH+vehicle, and (3) SAH+10 mg/kg rosuvastatin. Rosuvastatin or vehicle was orally administered to rats once daily from 7 days before to 1 day after the SAH operation. After SAH, we examined the effects of rosuvastatin on the neurologic score, brain water content, neuronal cell death estimated by terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate nick end labeling staining, blood-brain barrier disruption by immunoglobulin G (IgG) extravasation, oxidative stress, and proinflammatory molecules. RESULTS Compared with the vehicle group, rosuvastatin significantly improved the neurologic score and reduced the brain water content, neuronal cell death, and IgG extravasation. Rosuvastatin inhibited brain superoxide production, nuclear factor-kappa B (NF-κB) activation, and the increase in activated microglial cells after SAH. The increased expressions of tumor necrosis factor-alpha, endothelial matrix metalloproteinase-9, and neuronal cyclooxygenase-2 induced by SAH were prevented by rosuvastatin pretreatment. CONCLUSIONS The present study demonstrates that rosuvastatin pretreatment ameliorates EBI after SAH through the attenuation of oxidative stress and NF-κB-mediated inflammation.
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Affiliation(s)
- Ken Uekawa
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Yu Hasegawa
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Mingjie Ma
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Takashi Nakagawa
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Tetsuji Katayama
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Daisuke Sueta
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Kensuke Toyama
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Keiichiro Kataoka
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Nobutaka Koibuchi
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Takayuki Kawano
- Department of Neurosurgery, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Jun-ichi Kuratsu
- Department of Neurosurgery, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Shokei Kim-Mitsuyama
- Department of Pharmacology and Molecular Therapeutics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
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Erşahin M, Özsavcı D, Şener A, Özakpınar ÖB, Toklu HZ, Akakin D, Şener G, Yeğen BÇ. Obestatin alleviates subarachnoid haemorrhage-induced oxidative injury in rats via its anti-apoptotic and antioxidant effects. Brain Inj 2013; 27:1181-9. [PMID: 23895491 DOI: 10.3109/02699052.2013.804199] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Mehmet Erşahin
- School of Medicine, Department of Neurosurgery, Istanbul Medeniyet University
İstanbulTurkey
| | | | - Azize Şener
- School of Pharmacy, Department of Biochemistry
| | | | | | - Dilek Akakin
- School of Medicine, Department of Histology & Embryology
| | | | - Berrak Ç. Yeğen
- School of Medicine, Department of Physiology, Marmara University
IstanbulTurkey
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Kenny R, Cai G, Bayliss JA, Clarke M, Choo YL, Miller AA, Andrews ZB, Spencer SJ. Endogenous ghrelin's role in hippocampal neuroprotection after global cerebral ischemia: does endogenous ghrelin protect against global stroke? Am J Physiol Regul Integr Comp Physiol 2013; 304:R980-90. [PMID: 23576609 DOI: 10.1152/ajpregu.00594.2012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ghrelin is a gastrointestinal hormone with a well-characterized role in feeding and metabolism. Recent evidence suggests that ghrelin may also be neuroprotective after injury in animal models of cerebral ischemia. Thus exogenous ghrelin treatment can improve cell survival, reduce infarct size, and rescue memory deficits in focal ischemia models, doing so by suppressing inflammation and apoptosis. Endogenous ghrelin plays a key a role in a number of physiological processes, including feeding, metabolism, stress, and anxiety. However, no study has examined whether endogenous ghrelin also contributes to neuroprotection after cerebral ischemia. Here, we aimed to determine whether endogenous ghrelin normally protects against neuronal cell death and cognitive impairments after global cerebral ischemia and whether such changes are linked with inflammation or apoptosis. We used a two-vessel occlusion (2VO) model of global cerebral ischemia in wild-type (wt) and ghrelin knockout (ghr-/-) C57/Bl6J mice. ghr-/- mice had improved cell survival in the Cornu Ammonis(CA)-2/3 region of the hippocampus-a region of significant growth hormone secretagogue receptor expression. They also displayed less cellular degeneration than wt mice after the 2VO (Fluoro-Jade) and had less cognitive impairment in the novel object-recognition test. These outcomes were despite evidence of more neuroinflammation and apoptosis in the ghr-/- and less of a postsurgery hypothermia. Finally, we found that mortality in the week following the 2VO was reduced more in ghr-/- mice than in wt. Overall, these experiments point to a neurodegenerative but antiapoptotic effect of endogenous ghrelin in this model of global ischemia, highlighting that further research is essential before we can apply ghrelin treatments to neurodegenerative insults in the clinic.
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Affiliation(s)
- Rachel Kenny
- School of Health Sciences and Health Innovations Research Institute, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
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61
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The role of ghrelin in neuroprotection after ischemic brain injury. Brain Sci 2013; 3:344-59. [PMID: 24961317 PMCID: PMC4061836 DOI: 10.3390/brainsci3010344] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 02/19/2013] [Accepted: 03/07/2013] [Indexed: 12/11/2022] Open
Abstract
Ghrelin, a gastrointestinal peptide with a major role in regulating feeding and metabolism, has recently been investigated for its neuroprotective effects. In this review we discuss pre-clinical evidence suggesting ghrelin may be a useful therapeutic in protecting the brain against injury after ischemic stroke. Specifically, we will discuss evidence showing ghrelin administration can improve neuronal cell survival in animal models of focal cerebral ischemia, as well as rescue memory deficits. We will also discuss its proposed mechanisms of action, including anti-apoptotic and anti-inflammatory effects, and suggest ghrelin treatment may be a useful intervention after stroke in the clinic.
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Early brain injury: a common mechanism in subarachnoid hemorrhage and global cerebral ischemia. Stroke Res Treat 2013; 2013:394036. [PMID: 23533958 PMCID: PMC3603523 DOI: 10.1155/2013/394036] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 01/27/2013] [Indexed: 12/19/2022] Open
Abstract
Early brain injury (EBI) has become an area of extreme interest in the recent years and seems to be a common denominator in the pathophysiology of global transient ischemia and subarachnoid hemorrhage (SAH). In this paper, we highlight the importance of cerebral hypoperfusion and other mechanisms that occur in tandem in both pathologies and underline their possible roles in triggering brain injury after hemorrhagic or ischemic strokes.
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63
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Gül FC, Turgut B, Dağlı F, İlhan N, Özgen M. The comparison of the impact of ghrelin and tacrolimus on vitreous cytokine levels in an experimental uveitis model. Graefes Arch Clin Exp Ophthalmol 2013; 251:1235-41. [DOI: 10.1007/s00417-013-2259-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Revised: 12/05/2012] [Accepted: 01/02/2013] [Indexed: 10/27/2022] Open
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Turgut B, Gül FC, Dağli F, Ilhan N, Özgen M. Impact of ghrelin on vitreous cytokine levels in an experimental uveitis model. DRUG DESIGN DEVELOPMENT AND THERAPY 2013; 7:19-24. [PMID: 23341733 PMCID: PMC3546756 DOI: 10.2147/dddt.s39453] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Background The purpose of this study was to investigate the effect of intraperitoneal ghrelin on vitreous levels of interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-α) and to compare its effects with those of intraperitoneal infliximab in an experimental uveitis model. Methods Twenty-four male rats were assigned to four groups of six rats in each. All the rats, except for those in group 1 (controls), were injected intravitreally with concanavalin A to induce experimental uveitis. Rats in group 2 (sham) were not given any treatment after uveitis was induced. Rats in group 3 were given intraperitoneal infliximab 0.5 mg/100 mL on days 0, 1, 3, 5, and 7 following induction of uveitis on day 14 of the study. Rats in group 4 were given intraperitoneal ghrelin 10 ng/kg/day for 7 days following induction of uveitis. On day 21 of the study, enucleated globes were subjected to histopathologic examination. Vitreous levels of IL-1, IL-6, and TNF-α were measured by enzyme-linked immunosorbent assay. Results Vitreous levels of IL-1, IL-6, and TNF-α were significantly increased in the sham group relative to the control group (P < 0.05), but showed a significant decrease in the group treated with infliximab (P < 0.05). Cytokine levels also decreased in the ghrelin-treated group, but the decrease was not statistically significant (P > 0.05). Conclusion Ghrelin failed to decrease the IL-1, IL-6, and TNF-α levels that play a critical role in the pathogenesis of uveitis.
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Affiliation(s)
- Burak Turgut
- Department of Ophthalmology, School of Medicine, Fırat University, Elazig, Turkey.
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65
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Hossienzadeh F, Babri S, Alipour MR, Ebrahimi H, Mohaddes G. Effect of ghrelin on brain edema induced by acute and chronic systemic hypoxia. Neurosci Lett 2013; 534:47-51. [PMID: 23295905 DOI: 10.1016/j.neulet.2012.11.062] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Revised: 10/16/2012] [Accepted: 11/20/2012] [Indexed: 02/04/2023]
Abstract
Hypoxia is an important pathogenic factor for the induction of vascular leakage and brain edema formation. Recent studies suggest a role for TNF-α in the induction of brain edema. Ghrelin attenuates the synthesis of TNF-α following subarachnoid hemorrhage and traumatic brain injury (TBI). Therefore, we examined the effects of ghrelin on the brain edema, serum TNF-α levels and body weight in a systemic hypoxia model. Adult male Wistar rats were divided into acute and chronic controls, acute or chronic hypoxia and ghrelin-treated (80μg/kg/ip/daily) acute or chronic hypoxia groups. Systemic hypoxia was induced in rats by a normobaric hypoxic chamber (O(2) 11%) for two days (acute) or ten days (chronic). Effect of ghrelin on brain edema and serum TNF-α levels was assessed by dry-wet and ELISA method, respectively. The results showed that acute (P<0.001) and chronic (P<0.05) hypoxia caused an increase of brain water content. Administration of ghrelin only in the acute hypoxia group significantly (P<0.001) reduced brain water content. Acute hypoxia caused an increase of serum TNF-α level (P<0.001) and ghrelin significantly (P<0.001) reduced it. TNF-α level in chronic hypoxia did not change significantly. Both acute and chronic hypoxia decreased body weight significantly (P<0.001) and administration of ghrelin only could prevent further weight loss in chronic hypoxia group (P<0.001). Our findings show that administration of ghrelin may be useful in reducing brain edema induced by acute systemic hypoxia and at least part of the anti-edematous effects of ghrelin is due to decrease of serum TNF-α levels.
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Affiliation(s)
- Fezzeh Hossienzadeh
- Neuroscience Research Center of Tabriz University of Medical Sciences, Tabriz, Iran
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Lopez NE, Gaston L, Lopez KR, Coimbra RC, Hageny A, Putnam J, Eliceiri B, Coimbra R, Bansal V. Early ghrelin treatment attenuates disruption of the blood brain barrier and apoptosis after traumatic brain injury through a UCP-2 mechanism. Brain Res 2012; 1489:140-8. [PMID: 23099053 DOI: 10.1016/j.brainres.2012.10.031] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 09/11/2012] [Accepted: 10/16/2012] [Indexed: 01/04/2023]
Abstract
Ghrelin has been shown to be anti-inflammatory and neuroprotective in models of neurologic injury. We hypothesize that treatment with ghrelin will attenuate breakdown of the blood brain barrier (BBB) and apoptosis 24h following traumatic brain injury (TBI). We believe this protection is at least in part mediated by up-regulation of UCP-2, thereby stabilizing mitochondria and preventing up-regulation of caspase-3. A weight drop model was used to create severe TBI. Balb/c mice were divided into 3 groups. Sham: no TBI or ghrelin treatment; TBI: TBI only; TBI/ghrelin: 20μg (IP) ghrelin at the time of TBI. BBB permeability to 70kDa FITC-Dextran was measured 24h following injury and quantified in arbitrary integrated fluorescence (afu). Brain tissue was subjected to TUNEL staining and TUNEL positive cells were quantified. Immunohistochemistry was performed on injured tissue to reveal patterns of caspase-3 and UCP-2 expression. TBI increased cerebral vascular permeability by three-fold compared to sham. Ghrelin treatment restored vascular permeability to the level of shams. TUNEL staining showed that ghrelin mitigated the significant increase in apoptosis that follows TBI. TBI increased both caspase-3 compared to sham. Treatment with ghrelin significantly increased UCP-2 compared to TBI alone and this increase in UCP-2 expression was associated with a decrease in expression of caspase-3. Early ghrelin treatment prevents TBI induced BBB disruption and TBI mediated apoptosis 24h following injury. These results demonstrate the neuroprotective potential of ghrelin as a therapy in TBI.
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Affiliation(s)
- N E Lopez
- University of California San Diego, Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, 200W. Arbor Drive #8896, San Diego, CA 92103, USA.
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67
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Caner B, Hou J, Altay O, Fuj M, Zhang JH. Transition of research focus from vasospasm to early brain injury after subarachnoid hemorrhage. J Neurochem 2012; 123 Suppl 2:12-21. [DOI: 10.1111/j.1471-4159.2012.07939.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Basak Caner
- Department of Physiology; Loma Linda University, School of Medicine; Loma Linda; California; USA
| | - Jack Hou
- Department of Physiology; Loma Linda University, School of Medicine; Loma Linda; California; USA
| | - Orhan Altay
- Department of Physiology; Loma Linda University, School of Medicine; Loma Linda; California; USA
| | - Mutsumi Fuj
- Department of Physiology; Loma Linda University, School of Medicine; Loma Linda; California; USA
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68
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Vagal nerve stimulation decreases blood-brain barrier disruption after traumatic brain injury. J Trauma Acute Care Surg 2012; 72:1562-6. [DOI: 10.1097/ta.0b013e3182569875] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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69
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Hong Y, Guo S, Chen S, Sun C, Zhang J, Sun X. Beneficial effect of hydrogen-rich saline on cerebral vasospasm after experimental subarachnoid hemorrhage in rats. J Neurosci Res 2012; 90:1670-80. [PMID: 22589232 DOI: 10.1002/jnr.22739] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 06/02/2011] [Accepted: 06/16/2011] [Indexed: 01/10/2023]
Abstract
Cerebral vasospasm (CV) remains a common and devastating complication in patients with subarachnoid hemorrhage (SAH). Despite its clinical significance and extensive research, the underlying pathogenesis and therapeutic perspectives of CV remain incompletely understood. Recently, it has been suggested that molecular hydrogen (H(2)) can selectively reduce levels of hydroxyl radicals (·OH) and ameliorate oxidative and inflammatory injuries to organs in many models. However, whether H(2) can ameliorate CV after SAH is still unknown. This study was designed to evaluate the efficacy of H(2) in preventing SAH-induced CV. Experimental SAH was induced in Sprague-Dawley rats using cisterna magna blood injection. Hydrogen-rich saline (HS) was injected intraperitoneally (5 ml/kg) immediately and at 24 hr after injury. All rats were sacrificed 48 hr after the neurological examination scores had been recorded following SAH. Levels of oxidative stress and inflammation were evaluated. Basilar artery vasospasm was assessed by histological examination using light and transmission electron microscopy. HS treatment significantly improved neurological outcomes and attenuated morphological vasospasm of the basilar artery after SAH. In addition, we found that the beneficial effects of HS treatment on SAH-induced CV were associated with decreased levels of lipid peroxidation, increased activity of antioxidant enzymes, and reduced levels of proinflammatory cytokines in the basilar artery. These results indicate that H(2) has the potential to be a novel therapeutic strategy for the treatment of CV after SAH, and its neuroprotective effect might be partially mediated via limitation of vascular inflammation and oxidative stress.
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Affiliation(s)
- Yuan Hong
- Department of Neurosurgery, 2nd Affiliated Hospital, School of Medicine, Zhejiang University, Zhejiang, China
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70
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Dalvi PS, Belsham DD. Glucagon-like peptide-2 directly regulates hypothalamic neurons expressing neuropeptides linked to appetite control in vivo and in vitro. Endocrinology 2012; 153:2385-97. [PMID: 22416082 DOI: 10.1210/en.2011-2089] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Glucagon-like peptide-2 (GLP-2), a proglucagon-derived peptide, has been postulated to affect appetite at the level of the hypothalamus. To gain better insight into this process, a degradation-resistant GLP-2 analog, human (Gly(2))GLP-2(1-33) [h(Gly(2))GLP-2] was intracerebroventricularly injected into mice to examine its action on food and water intake and also activation of hypothalamic anorexigenic α-melanocyte-stimulating hormone/proopiomelanocortin, neurotensin, and orexigenic neuropeptide Y, and ghrelin neurons. Central h(Gly(2))GLP-2 administration significantly suppressed food and water intake with acute weight loss at 2 h. Further, central h(Gly(2))GLP-2 robustly induced c-Fos activation in the hypothalamic arcuate, dorsomedial, ventromedial, paraventricular, and the lateral hypothalamic nuclei. We found differential colocalization of neuropeptides with c-Fos in specific regions of the hypothalamus. To assess whether hypothalamic neuropeptides are directly regulated by GLP-2 in vitro, we used an adult-derived clonal, immortalized hypothalamic cell line, mHypoA-2/30, that endogenously expresses functional GLP-2 receptors (GLP-2R) and two of the feeding-related neuropeptides linked to GLP-2R activation in vivo: neurotensin and ghrelin. Treatment with h(Gly(2))GLP-2 stimulated c-Fos expression and phosphorylation of cAMP response element-binding protein/activating transcription factor-1. In addition, treatment with h(Gly(2))GLP-2 significantly increased neurotensin and ghrelin mRNA transcript levels by 50 and 95%, respectively, at 24 h after treatment in protein kinase A-dependent manner. Taken together, these findings implicate the protein kinase A pathway as the means by which GLP-2 can up-regulate hypothalamic neuropeptide mRNA levels and provide evidence for a link between central GLP-2R activation and specific hypothalamic neuropeptides involved in appetite regulation.
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Affiliation(s)
- Prasad S Dalvi
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
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71
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Dalvi PS, Nazarians-Armavil A, Purser MJ, Belsham DD. Glucagon-like peptide-1 receptor agonist, exendin-4, regulates feeding-associated neuropeptides in hypothalamic neurons in vivo and in vitro. Endocrinology 2012; 153:2208-22. [PMID: 22334721 DOI: 10.1210/en.2011-1795] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Exendin-4, a long-acting glucagon-like peptide-1 receptor (GLP-1R) agonist, is a potential regulator of feeding behavior through its ability to inhibit gastric emptying, reduce food intake, and induce satiety. GLP-1R activation by exendin-4 induces anorexia; however, the specific populations of neuropeptidergic neurons activated by exendin-4 within the hypothalamus, the central regulator of energy homeostasis, remain unclear. This study determines whether exendin-4 regulates hypothalamic neuropeptide expression and explores the signaling mechanisms involved. The distribution and quantity of exendin-4-induced c-Fos immunoreactivity were evaluated to determine activation of α-melanocyte-stimulating hormone/proopiomelanocortin, neuropeptide Y, neurotensin (NT), and ghrelin neurons in hypothalamic nuclei during exendin-4-induced anorexia in mice. Additionally, exendin-4 action on NT and ghrelin transcript regulation was examined in immortalized hypothalamic neurons. With anorexia induced by intracerebroventricular exendin-4, α-melanocyte-stimulating hormone/proopiomelanocortin and neuropeptide Y neurons were activated in the arcuate nucleus, with simultaneous activation of NT-expressing neurons in the paraventricular nucleus, and ghrelin-expressing neurons in the arcuate nucleus, paraventricular nucleus, and periventricular hypothalamus, suggesting that neurons in one or more of these areas mediate the anorexic action of exendin-4. In the hypothalamic neuronal cell models, exendin-4 increased cAMP, cAMP response element-binding protein/activating transcription factor-1 and c-Fos activation, and via a protein kinase A-dependent mechanism regulated NT and ghrelin mRNA expression, indicating that these neuropeptides may serve as downstream mediators of exendin-4 action. These findings provide a previously unrecognized link between central GLP-1R activation by exendin-4 and the regulation of hypothalamic NT and ghrelin. Further understanding of this central GLP-1R activation may lead to safe and effective therapeutics for the treatment of metabolic disorders.
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Affiliation(s)
- Prasad S Dalvi
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
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72
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Lee S, Kim Y, Li E, Park S. Ghrelin protects spinal cord motoneurons against chronic glutamate excitotoxicity by inhibiting microglial activation. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2012; 16:43-8. [PMID: 22416219 PMCID: PMC3298825 DOI: 10.4196/kjpp.2012.16.1.43] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 01/01/2012] [Accepted: 01/08/2012] [Indexed: 11/17/2022]
Abstract
Glutamate excitotoxicity is emerging as a contributor to degeneration of spinal cord motoneurons in amyotrophic lateral sclerosis (ALS). Recently, we have reported that ghrelin protects motoneurons against chronic glutamate excitotoxicity through the activation of extracellular signal-regulated kinase 1/2 and phosphatidylinositol-3-kinase/Akt/glycogen synthase kinase-3β pathways. Previous studies suggest that activated microglia actively participate in the pathogenesis of ALS motoneuron degeneration. However, it is still unknown whether ghrelin exerts its protective effect on motoneurons via inhibition of microglial activation. In this study, we investigate organotypic spinal cord cultures (OSCCs) exposed to threohydroxyaspartate (THA), as a model of excitotoxic motoneuron degeneration, to determine if ghrelin prevents microglial activation. Exposure of OSCCs to THA for 3 weeks produced typical motoneuron death, and treatment of ghrelin significantly attenuated THA-induced motoneuron loss, as previously reported. Ghrelin prevented THA-induced microglial activation in the spinal cord and the expression of pro-inflammatory cytokines tumor necrosis factor-α and interleukin-1β. Our data indicate that ghrelin may act as a survival factor for motoneurons by functioning as a microglia-deactivating factor and suggest that ghrelin may have therapeutic potential for the treatment of ALS and other neurodegenerative disorders where inflammatory responses play a critical role.
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Affiliation(s)
- Sungyoub Lee
- Department of Pharmacology and Medical Research Center for Bioreaction to ROS and Biomedical Science Institute, School of Medicine, Kyung Hee University, Seoul 130-701, Korea
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73
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Stengel A, Taché Y. Ghrelin - a pleiotropic hormone secreted from endocrine x/a-like cells of the stomach. Front Neurosci 2012; 6:24. [PMID: 22355282 PMCID: PMC3280431 DOI: 10.3389/fnins.2012.00024] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Accepted: 01/29/2012] [Indexed: 12/13/2022] Open
Abstract
The gastric X/A-like endocrine cell receives growing attention due to its peptide products with ghrelin being the best characterized. This peptide hormone was identified a decade ago as a stimulator of food intake and to date remains the only known peripherally produced and centrally acting orexigenic hormone. In addition, subsequent studies identified numerous other functions of this peptide including the stimulation of gastrointestinal motility, the maintenance of energy homeostasis and an impact on reproduction. Moreover, ghrelin is also involved in the response to stress and assumed to play a role in coping functions and exert a modulatory action on immune pathways. Our knowledge on the regulation of ghrelin has markedly advanced during the past years by the identification of the ghrelin acylating enzyme, ghrelin-O-acyltransferase, and by the description of changes in expression, activation, and release under different metabolic as well as physically and psychically challenging conditions. However, our insight on regulatory processes of ghrelin at the cellular and subcellular levels is still very limited and warrants further investigation.
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Affiliation(s)
- Andreas Stengel
- Division Psychosomatic Medicine and Psychotherapy, Department of Medicine, Charité - Universitätsmedizin Berlin Berlin, Germany
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74
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Tomoda K, Kubo K, Nishii Y, Yamamoto Y, Yoshikawa M, Kimura H. Changes of ghrelin and leptin levels in plasma by cigarette smoke in rats. J Toxicol Sci 2012; 37:131-8. [DOI: 10.2131/jts.37.131] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Koichi Tomoda
- Second Department of Internal Medicine, Nara Medical University
| | - Kaoru Kubo
- Laboratory Animal Research Center, Nara Medical University
| | | | | | | | - Hiroshi Kimura
- Second Department of Internal Medicine, Nara Medical University
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75
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Lopez NE, Krzyzaniak MJ, Blow C, Putnam J, Ortiz-Pomales Y, Hageny AM, Eliceiri B, Coimbra R, Bansal V. Ghrelin prevents disruption of the blood-brain barrier after traumatic brain injury. J Neurotrauma 2011; 29:385-93. [PMID: 21939391 DOI: 10.1089/neu.2011.2053] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Significant effort has been focused on reducing neuronal damage from post-traumatic brain injury (TBI) inflammation and blood-brain barrier (BBB)-mediated edema. The orexigenic hormone ghrelin decreases inflammation in sepsis models, and has recently been shown to be neuroprotective following subarachnoid hemorrhage. We hypothesized that ghrelin modulates cerebral vascular permeability and mediates BBB breakdown following TBI. Using a weight-drop model, TBI was created in three groups of mice: sham, TBI, and TBI/ghrelin. The BBB was investigated by examining its permeability to FITC-dextran and through quantification of perivascualar aquaporin-4 (AQP-4). Finally, we immunoblotted for serum S100B as a marker of brain injury. Compared to sham, TBI caused significant histologic neuronal degeneration, increases in vascular permeability, perivascular expression of AQP-4, and serum levels of S100B. Treatment with ghrelin mitigated these effects; after TBI, ghrelin-treated mice had vascular permeability and perivascular AQP-4 and S100B levels that were similar to sham. Our data suggest that ghrelin prevents BBB disruption after TBI. This is evident by a decrease in vascular permeability that is linked to a decrease in AQP-4. This decrease in vascular permeability may diminish post-TBI brain tissue damage was evident by decreased S100B.
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Affiliation(s)
- Nicole E Lopez
- Department of Surgery, University of California-San Diego, San Diego, California, USA
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76
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Baatar D, Patel K, Taub DD. The effects of ghrelin on inflammation and the immune system. Mol Cell Endocrinol 2011; 340:44-58. [PMID: 21565248 DOI: 10.1016/j.mce.2011.04.019] [Citation(s) in RCA: 189] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 04/15/2011] [Accepted: 04/22/2011] [Indexed: 12/25/2022]
Abstract
A number of hormones and metabolic mediators signal the brain of changes in the body's energy status and when an imbalance occurs; the brain coordinates the appropriate changes in energy intake and utilization via the control of appetite and food consumption. Under conditions of chronic inflammation and immune activation, there is often a significant loss of body mass and appetite suggesting the presence of shared ligands and signaling pathways mediating "crosstalk" between the immune and neuroendocrine systems. Ghrelin, the endogenous ligand for growth hormone secretagogue receptor (GHS-R), is produced primarily by cells in the stomach and serves as a potent circulating orexigenic hormone controlling food intake, energy expenditure, adiposity and GH secretion. The functional roles of ghrelin and other growth hormone secretagogues (GHS) within the immune system and under states of inflammatory stress and injury are only now coming to light. A number of reports over the past decade have described ghrelin to be a potent anti-inflammatory mediator both in vitro and in vivo and a promising therapeutic agent in the treatment of inflammatory diseases and injury. Moreover, ghrelin has also been shown to promote lymphocyte development in the primary lymphoid organs (bone marrow and thymus) and to ablate age-associated thymic involution. In the current report, we review the literature supporting a role for ghrelin as an anti-inflammatory agent and immunoregulatory hormone/cytokine and its potential use in the treatment of inflammatory diseases and injury.
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Affiliation(s)
- Dolgor Baatar
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Biomedical Research Center, Baltimore, MD 21224, USA
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77
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Özsavcí D, Erşahin M, Şener A, Özakpinar ÖB, Toklu HZ, Akakín D, Şener G, Yeğen BÇ. The Novel Function of Nesfatin-1 as an Anti-inflammatory and Antiapoptotic Peptide in Subarachnoid Hemorrhage–Induced Oxidative Brain Damage in Rats. Neurosurgery 2011; 68:1699-708; discussion 1708. [PMID: 21336215 DOI: 10.1227/neu.0b013e318210f258] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Affiliation(s)
| | | | - Azize Şener
- School of Pharmacy, Department of Biochemistry
| | | | - Hale Z. Toklu
- School of Medicine, Department of Histology and Embryology
| | - Dilek Akakín
- School of Medicine, Department of Physiology, Marmara University, Istanbul, Turkey
| | - Göksel Şener
- School of Medicine, Department of Histology and Embryology
| | - Berrak Ç Yeğen
- Samsun Education and Research Hospital, Department of Neurosurgery, Istanbul, Turkey
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78
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Current world literature. Curr Opin Pediatr 2011; 23:356-63. [PMID: 21566469 DOI: 10.1097/mop.0b013e3283481706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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79
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Current world literature. Curr Opin Endocrinol Diabetes Obes 2011; 18:83-98. [PMID: 21178692 DOI: 10.1097/med.0b013e3283432fa7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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80
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Erşahin M, Toklu HZ, Akakin D, Yuksel M, Yeğen BC, Sener G. The effects of Nigella sativa against oxidative injury in a rat model of subarachnoid hemorrhage. Acta Neurochir (Wien) 2011; 153:333-41. [PMID: 21072672 DOI: 10.1007/s00701-010-0853-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 10/23/2010] [Indexed: 01/10/2023]
Abstract
OBJECTIVE The aim of the study was to investigate the putative neuroprotective effect of Nigella sativa oil (NSO) treatment against subarachnoid hemorrhage (SAH) in rats. METHODS To induce SAH, rats were injected with 0.3 ml blood into their cisterna magna. Male Wistar albino rats were divided as control, vehicle-treated SAH, and NSO-treated (0.2 ml/kg, intraperitoneally) SAH groups. Forty-eight hours after SAH induction, neurological examination scores were recorded and the rats were decapitated. Brain tissue samples were taken for blood brain barrier permeability, brain water content, or determination of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO), and Na(+)-K(+)-ATPase activities. RESULTS AND DISCUSSION On the second day of SAH induction, neurological examination scores were increased in SAH groups, while SAH caused significant decreases in brain GSH content and Na(+)-K(+)-ATPase activity, which were accompanied with significant increases in MDA levels and MPO activity. The histological observation showed vasospasm of the basillary artery. On the other hand, NSO treatment markedly improved the neurological scores while all oxidant responses were prevented, implicating that NSO treatment may be of therapeutic use in preventing oxidative stress due to SAH.
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Affiliation(s)
- Mehmet Erşahin
- Department of Neurosurgery, Haydarpasa Numune Education and Research Hospital, Istanbul, Turkey
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81
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Chung H, Chung HY, Bae CW, Kim CJ, Park S. Ghrelin suppresses tunicamycin- or thapsigargin-triggered endoplasmic reticulum stress-mediated apoptosis in primary cultured rat cortical neuronal cells. Endocr J 2011; 58:409-20. [PMID: 21490406 DOI: 10.1507/endocrj.k10e-396] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Ghrelin functions as a neuroprotective agent and rescues neurons from various insults. However, the molecular mechanisms underlying ghrelin neuroprotection remains to be elucidated. An accumulation of unfolded proteins in the endoplasmic reticulum (ER) leads to ER stress and then induces ER stress-mediated cell death. Here, we report that acylated ghrelin inhibited tunicamycin- or thapsigargin-triggered ER stress-induced apoptotic cell death in primary rat cortical neurons. An analysis using a specific inhibitor of phosphatidylinositol-3-kinase (PI3K), LY294002, showed that ghrelin prevented apoptosis via the activation of PI3K signaling pathway. Ghrelin suppressed tunicamycin- or thapsigargin-induced upregulation and nuclear translocation of C/EBP homologous protein (CHOP). Ghrelin also inhibited tunicamycin or thapsigargin induction of PRK-like ER kinase (PERK), eukaryotic translation initiation factor-2α (eIF2α) and activating transcription factor (ATF) 4. Exposure of cells to tunicamycin or thapsigargin resulted in nuclear translocation of forkhead box protein O1 (Foxo1), which was reduced by pretreatment with ghrelin. The protective effect of ghrelin was accompanied by an increased phosphorylation of Akt and glycogen synthase kinase (GSK)-3β. Furthermore, ghrelin phosphorylated and inactivated pro-apoptotic BAD and Foxo1. In addition, phospho-Akt was translocated to the nucleus in response to ghrelin and PI3K inhibition by LY294002 prevented ghrelin-induced effect on phospho-Akt localization. Our study suggests that suppression of CHOP activation via the inhibition of PERK/eIF2α/ATF4 pathway and prevention of Foxo1 activation and nuclear translocation may contribute to ghrelin-mediated neuroprotection during ER stress responses. Our data also suggest that PI3K/Akt-mediated inactivation of GSK-3β, BAD and Foxo1 may be associated with the anti-apoptotic effect of ghrelin.
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Affiliation(s)
- Hyunju Chung
- Department of Core Research Laboratory, Clinical Research Institute, The East-West Neo Medical Center, School of Medicine, Kyung Hee University, Gangdong-gu, Seoul, Korea
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82
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Bansal V, Ryu SY, Blow C, Costantini T, Loomis W, Eliceiri B, Baird A, Wolf P, Coimbra R. The Hormone Ghrelin Prevents Traumatic Brain Injury Induced Intestinal Dysfunction. J Neurotrauma 2010; 27:2255-60. [DOI: 10.1089/neu.2010.1372] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Vishal Bansal
- Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego, San Diego, California
| | - Seok Yong Ryu
- Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego, San Diego, California
- Department of Emergency Medicine, Inje University, Sanggye Paik Hospital, South Korea
| | - Chelsea Blow
- Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego, San Diego, California
| | - Todd Costantini
- Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego, San Diego, California
| | - William Loomis
- Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego, San Diego, California
| | - Brian Eliceiri
- Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego, San Diego, California
| | - Andrew Baird
- Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego, San Diego, California
| | - Paul Wolf
- Department of Pathology, University of California San Diego, San Diego, California
| | - Raul Coimbra
- Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego, San Diego, California
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83
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Andrews ZB. The extra-hypothalamic actions of ghrelin on neuronal function. Trends Neurosci 2010; 34:31-40. [PMID: 21035199 DOI: 10.1016/j.tins.2010.10.001] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 09/30/2010] [Accepted: 10/01/2010] [Indexed: 12/20/2022]
Abstract
Ghrelin is a peptide hormone produced and secreted in the stomach. Numerous studies over the past decade demonstrate its importance in food intake, body-weight regulation and glucose homeostasis. These effects are driven largely by the high expression of the ghrelin receptor (GHSR1a) in the hypothalamus. However, GHSR1a is also expressed in numerous extra-hypothalamic neuronal populations, suggesting that ghrelin has physiological functions besides those involved in metabolic functions. In this review, I focus on increasing evidence that ghrelin has important roles in extra-hypothalamic functions, including learning and memory, reward and motivation, anxiety and depression, and neuroprotection. Furthermore, I discuss how the recently demonstrated role of ghrelin in promoting survival during periods of caloric restriction could contribute to its inherent neuroprotective and neuromodulatory properties.
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Affiliation(s)
- Zane B Andrews
- Department of Physiology, Monash University, Clayton, VIC 3183, Australia.
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