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Song J, Ouyang F, Xiong Y, Luo Q, Jiang H, Fan L, Zhang Z. Reassessment of oxidative stress in idiopathic sudden hearing loss and preliminary exploration of the effect of physiological concentration of melatonin on prognosis. Front Neurol 2023; 14:1249312. [PMID: 37745649 PMCID: PMC10511764 DOI: 10.3389/fneur.2023.1249312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 08/18/2023] [Indexed: 09/26/2023] Open
Abstract
Background and purpose The pathogenesis of idiopathic sudden sensorineural hearing loss (ISSNHL) is still unclear, and there is no targeted treatment. This research aimed to verify the role of oxidative stress in ISSNHL and explore whether melatonin has a protective effect on hearing. Materials and methods A total of 43 patients with ISSNHL and 15 healthy controls were recruited to detect the level of melatonin, reactive oxygen species (ROS), and total antioxidant capacity (TAC) in the blood and compared before and after treatment. Multivariate logistic regression models were performed to assess the factors relevant to the occurrence and improvement of ISSNHL. Results The patients with ISSNHL showed significantly higher ROS levels than controls (4.42 ± 4.40 vs. 2.30 ± 0.59; p = 0.031). The levels of basal melatonin were higher (1400.83 ± 784.89 vs. 1095.97 ± 689.08; p = 0.046) and ROS levels were lower (3.05 ± 1.81 vs. 5.62 ± 5.56; p = 0.042) in the effective group as compared with the ineffective group. Logistic regression analysis showed that melatonin (OR = 0.999, 95% CI 0.997-1.000, p = 0.049), ROS (OR = 1.154, 95% CI 1.025-2.236, p = 0.037), and vertigo (OR = 3.011, 95% CI 1.339-26.983, p = 0.019) were independent factors associated with hearing improvement. Besides, the level of melatonin (OR = 0.999, 95% CI 0.998-1.000, p = 0.023) and ROS (OR = 3.248, 95% CI 1.109-9.516, p = 0.032) were associated with the occurrence of ISSNHL. Conclusion Our findings may suggest oxidative stress involvement in ISSNHL etiopathogenesis. The level of melatonin and ROS, and vertigo appear to be predictive of the effectiveness of hearing improvement following ISSNHL treatment.
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Affiliation(s)
- Jianxiong Song
- Department of Otolaryngology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Fang Ouyang
- Department of Endocrinology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yuanping Xiong
- Department of Otolaryngology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Qing Luo
- Department of Otolaryngology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Hongqun Jiang
- Department of Otolaryngology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Li Fan
- Department of Otolaryngology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Zhiyuan Zhang
- Department of Otolaryngology, The First Affiliated Hospital of Nanchang University, Nanchang, China
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The protective effects of caffeine and melatonin on antioxidant enzymes in rat fetal lung tissues. JOURNAL OF SURGERY AND MEDICINE 2019. [DOI: 10.28982/josam.598742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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3
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Hosseinzadeh A, Javad-Moosavi SA, Reiter RJ, Yarahmadi R, Ghaznavi H, Mehrzadi S. Oxidative/nitrosative stress, autophagy and apoptosis as therapeutic targets of melatonin in idiopathic pulmonary fibrosis. Expert Opin Ther Targets 2018; 22:1049-1061. [PMID: 30445883 DOI: 10.1080/14728222.2018.1541318] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease associated with disruption of alveolar epithelial cell layer and expansion of fibroblasts/myofibroblasts. Excessive levels of oxidative/nitrosative stress, induction of apoptosis, and insufficient autophagy may be involved in IPF pathogenesis; hence, the targeting of these pathways may ameliorate IPF. Areas covered: We describe the ameliorative effect of melatonin on IPF. We summarize the research on IPF pathogenesis with a focus on oxidative/nitrosative stress, autophagy and apoptosis pathways and discuss the potential effects of melatonin on these pathways. Expert opinion: Oxidative/nitrosative stress, apoptosis and autophagy could be interesting targets for therapeutic intervention in IPF. Melatonin, as a potent antioxidant, induces the expression of antioxidant enzymes, scavenges free radicals and modulates apoptosis and autophagy pathways. The effect of melatonin in the induction of autophagy could be an important mechanism against fibrotic process in IPF lungs. Further clinical studies are necessary to determine if melatonin could be a candidate for treating IPF.
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Affiliation(s)
- Azam Hosseinzadeh
- a Razi Drug Research Center , Iran University of Medical Sciences , Tehran , Iran
| | | | - Russel J Reiter
- c Department of Cellular and Structural Biology , UT Health , San Antonio , TX , USA
| | - Rasoul Yarahmadi
- d Department of Occupational Health , Air Pollution Research Center, Iran University of Medical Sciences , Tehran , Iran
| | - Habib Ghaznavi
- e Department of Pharmacology , School of Medicine, Zahedan University of Medical Sciences , Zahedan , Iran
| | - Saeed Mehrzadi
- a Razi Drug Research Center , Iran University of Medical Sciences , Tehran , Iran
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Hosseinzadeh A, Javad-Moosavi SA, Reiter RJ, Hemati K, Ghaznavi H, Mehrzadi S. Idiopathic pulmonary fibrosis (IPF) signaling pathways and protective roles of melatonin. Life Sci 2018; 201:17-29. [PMID: 29567077 DOI: 10.1016/j.lfs.2018.03.032] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/13/2018] [Accepted: 03/15/2018] [Indexed: 12/19/2022]
Abstract
Idiopathic pulmonary fibrosis (IPF) is characterized by the progressive loss of lung function due to tissue scarring. A variety of pro-inflammatory and pro-fibrogenic factors including interleukin‑17A, transforming growth factor β, Wnt/β‑catenin, vascular endothelial growth factor, platelet-derived growth factor, fibroblast growth factors, endotelin‑1, renin angiotensin system and impaired caveolin‑1 function are involved in the IPF pathogenesis. Current therapies for IPF have some limitations and this highlights the need for effective therapeutic agents to treat this fatal disease. Melatonin and its metabolites are broad-spectrum antioxidants that not only remove reactive oxygen and nitrogen species by radical scavenging but also up-regulate the expression and activity of endogenous antioxidants. Via these actions, melatonin and its metabolites modulate a variety of molecular pathways in different pathophysiological conditions. Herein, we review the signaling pathways involved in the pathophysiology of IPF and the potentially protective effects of melatonin on these pathways.
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Affiliation(s)
- Azam Hosseinzadeh
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran
| | | | - Russel J Reiter
- Department of Cellular and Structural Biology, UT Health, San Antonio, TX, USA
| | - Karim Hemati
- Department of Anesthesiology, Iran University of Medical Sciences, Tehran, Iran; Department of Anesthesiology, Ilam University of Medical Sciences, Ilam, Iran
| | - Habib Ghaznavi
- Department of Pharmacology, School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran
| | - Saeed Mehrzadi
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran.
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5
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Repetitive hyperbaric oxygen therapy provides better effects on brain inflammation and oxidative damage in rats with focal cerebral ischemia. J Formos Med Assoc 2014; 113:620-8. [DOI: 10.1016/j.jfma.2014.03.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2013] [Revised: 03/27/2014] [Accepted: 03/27/2014] [Indexed: 11/22/2022] Open
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6
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Paintlia AS, Paintlia MK, Mohan S, Singh AK, Singh I. AMP-activated protein kinase signaling protects oligodendrocytes that restore central nervous system functions in an experimental autoimmune encephalomyelitis model. THE AMERICAN JOURNAL OF PATHOLOGY 2013; 183:526-41. [PMID: 23759513 DOI: 10.1016/j.ajpath.2013.04.030] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 04/22/2013] [Accepted: 04/29/2013] [Indexed: 12/12/2022]
Abstract
AMP-activated protein kinase (AMPK) signaling is reported to protect neurons under pathologic conditions; however, its effect on oligodendrocytes (OLs) remains to be elucidated. We investigated whether AMPK signaling protects OLs to restore central nervous system (CNS) functions in an experimental autoimmune encephalomyelitis (EAE), a murine model of multiple sclerosis. Increased inflammation and demyelination in the CNS and peripheral immune responses were consistent with the observed clinical impairments in EAE animals, which were attenuated by treatment with metformin compared with vehicle. In addition, expressions of neurotrophic factors and of signatory genes of OL lineages were increased in the CNS of metformin-treated EAE animals. Likewise, metformin attenuated inflammatory response and enhanced expressions of neurotrophic factors, thereby protecting OLs via AMPK activation in mixed glial cultures stimulated with lipopolysaccharide/interferon γ in vitro, as evidenced by analysis of the expression of signatory genes of O1(+)/MBP(+) OLs and their cellular populations. Metformin also attenuated oxidative stress and malondialdehyde-containing protein levels, with corresponding induction of antioxidative defenses in OLs exposed to cytokines via AMPK activation. These effects of metformin were evident in the CNS of EAE animals. These data provide evidence that AMPK signaling is crucial to protect OLs and, thus, CNS functions in EAE animals. We conclude that AMPK activators, including metformin, have the potential to limit neurologic deficits in multiple sclerosis and related neurodegenerative disorders.
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Affiliation(s)
- Ajaib S Paintlia
- Darby Children's Research Institute, Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina 29425, USA
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Zhang Y, Li L, Xiang C, Ma Z, Ma T, Zhu S. Protective effect of melatonin against Adriamycin-induced cardiotoxicity. Exp Ther Med 2013; 5:1496-1500. [PMID: 23737906 PMCID: PMC3671825 DOI: 10.3892/etm.2013.989] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 02/26/2013] [Indexed: 12/05/2022] Open
Abstract
The aim of this in vivo study was to explore the protective properties of melatonin against Adriamycin-induced myocardial toxicity. A rat model of breast cancer was established and the rats were randomly divided into the blank group (Blank), the solvent group [Diss; dehydrated alcohol: physiological saline (1:9)], the Adriamycin group (ADM), the melatonin group (MLT) and the melatonin + Adriamycin group (M+A). The concentrations of lipid peroxide (LPO), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in myocardial tissues were detected, the changes in myocardial tissues were observed using light microscopy and electron microscopy, and the 1-month survival rates of each group of rats were compared. Breast cancer was established in 116 rats. In the ADM group, the concentration of LPO was higher and the concentrations of SOD and GSH-Px were significantly lower than those in the blank group. In the M+A group, compared with the ADM group, the concentration of LPO was lower (P<0.05) and the concentrations of SOD and GSH-Px were higher (P<0.05). It was observed using light and electron microscopy that the myocardial injuries to the M+A group were significantly alleviated in comparison with those in the ADM group; the 1-month survival rate in the M+A group was higher than that in the ADM group. Melatonin may have a protective role in the myocardium by reducing Adriamycin-induced myocardial oxidative damage.
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Affiliation(s)
- Yan Zhang
- Departments of Oncology, The First Hospital of Shijiazhuang, Shijiazhuang, Hebei 050010
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8
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Simsek K, Ozler M, Ucar E, Sadir S, Demirbas S, Uysal B, Ay H. Pressure-related effects of hyperbaric oxygen exposure on oxidation products and antioxidant enzymes in the rat lung. ACTA ACUST UNITED AC 2011. [DOI: 10.5455/jeim.130111.or.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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9
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Ay H, Uzun G, Onem Y, Aydinoz S, Yildiz S, Bilgi O, Topal T, Atasoyu EM. Effect of Hyperbaric Oxygen on Cyclosporine-Induced Nephrotoxicity and Oxidative Stress in Rats. Ren Fail 2009; 29:495-501. [PMID: 17497475 DOI: 10.1080/08860220701274983] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Reactive oxygen species have been suggested to be involved in cyclosporine nephrotoxicity. Hyperbaric oxygen is known to induce the generation of reactive oxygen species in tissues. The aim of this study was to investigate whether the use of hyperbaric oxygen concurrently with cyclosporine potentiates cyclosporine nephrotoxicity by inducing oxidative stress in kidneys. The study consisted of four groups of rats: a control group, a cyclosporine group (15 mg/kg/day intraperitoneally for 14 days), a hyperbaric oxygen group (60 min. every day for five days at 2.5 atmosphere absolute), and a cyclosporine + hyperbaric oxygen group (cyclosporine 15 mg/kg/day intraperitoneally for 14 days + hyperbaric oxygen for 60 min at 2.5 atmosphere absolute every day for five days on the last five days of cyclosporine treatment). Oxidative stress was determined by measuring renal thiobarbituric acid-reactive substances content, renal superoxide dismutase, and glutathione peroxidase activities. Cyclosporine increased serum urea and creatinine levels, indicating the development of nephrotoxicity, and induced significant oxidative stress in rat kidneys. Hyperbaric oxygen alone did not alter any of the biochemical and oxidative stress parameters compared to the control group. When used concurrently with cyclosporine, hyperbaric oxygen significantly reduced cyclosporine-induced oxidative stress, but it neither attenuated nor aggravated cyclosporine-induced nephrotoxicity. These results suggest that reactive oxygen species are involved in cyclosporine nephrotoxicity, but are not the direct cause of the toxicity. Although concurrent use of cyclosporine and hyperbaric oxygen did not exacerbate cyclosporine nephrotoxicity in this model, we recommend that the renal functions of patients be monitored periodically when these treatments are used concurrently.
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Affiliation(s)
- Hakan Ay
- Department of Undersea and Hyperbaric Medicine, Gulhane Military Medical Academy, Haydarpasa Training Hospital, Uskudar, Istanbul, Turkey
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10
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Ozen OA, Kus MA, Kus I, Alkoc OA, Songur A. Protective effects of melatonin against formaldehyde-induced oxidative damage and apoptosis in rat testes: an immunohistochemical and biochemical study. Syst Biol Reprod Med 2008; 54:169-76. [PMID: 18942024 DOI: 10.1080/19396360802422402] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
This study investigated the protective effects of melatonin against formaldehyde-induced oxidative damage and apoptosis in rat testes. A total of 21 male Wistar rats were divided into three groups. Group I was used as a control, Group II was injected every other day with formaldehyde for 1 month, whereas Group III was injected every other day with formaldehyde and melatonin for 1 month. At the end of the experimental period animals were sacrificed and the testes removed and dissected from the surrounding tissues for immunohistochemical evaluation. In addition, the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) were determined. The levels of SOD and GSH-Px decreased significantly, whereas the level of MDA significantly increased in animals treated with formaldehyde compared with the controls. Apoptosis of spermatogenetic and Leydig cells of testicular tissues was observed. In contrast, rats with melatonin SOD and GSH-Px enzyme activity increased whereas MDA levels decreased with formaldehyde exposure along with apoptosis. In view of the present findings, it is suggested that melatonin treatment may prevent formaldehyde-induced oxidative damage and apoptosis in rat testes.
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Affiliation(s)
- Oguz Aslan Ozen
- Faculty of Medicine, Department of Anatomy, Afyon Kocatepe University, Afyon, Turkey.
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11
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Wang L, Wang W, Zhao M, Ma L, Li M. Psychological stress induces dysregulation of iron metabolism in rat brain. Neuroscience 2008; 155:24-30. [PMID: 18555617 DOI: 10.1016/j.neuroscience.2008.03.091] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 03/31/2008] [Accepted: 03/31/2008] [Indexed: 01/07/2023]
Abstract
Oxidative damage induced by abnormal iron accumulation in the brain is a primary cause of many neurodegenerative diseases, while the reason for iron deposition remains unclear. A previous study reported that various kinds of stress could cause a change in iron level and psychological stress (PS) was a risk factor for neuron death. In the present study we investigated the influence of PS on iron metabolism in rat brain. The results showed that both total iron and non-protein-bound-iron (NPBI) levels were higher in the cerebral cortex, hippocampus and striatum of PS rats. The levels of iron regulatory factors, including transferrin receptor 1 (TfR1), ferritin (Fn), and iron regulatory protein1 (IRP1), were all changed in the iron deposition regions of the PS-exposed rat brain, accompanied by intensified oxidative stress. It is concluded that PS can increase the intake of iron in some regions of brain and subsequently causes regional iron accumulation, indicating PS might be an important reason for iron deposition-caused neurodegenerative diseases.
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Affiliation(s)
- L Wang
- Department of Military Hygiene, Second Military Medical University, Shanghai, China
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12
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Kurt B, Kurt Y, Karslioğlu Y, Topal T, Erdamar H, Korkmaz A, Türközkan N, Yaman H, Odabaşi Z, Günhan O. Effects of hyperbaric oxygen on energy production and xanthine oxidase levels in striated muscle tissue of healthy rats. J Clin Neurosci 2008; 15:445-50. [PMID: 18280739 DOI: 10.1016/j.jocn.2007.01.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2006] [Revised: 01/17/2007] [Accepted: 01/21/2007] [Indexed: 11/28/2022]
Abstract
We investigated the effects of hyperbaric oxygen (HBO) treatment on striated muscle tissue in healthy rats. The treatment group of rats (n=16) was given HBO daily on weekdays for 2 h over a 4-week period while a control group (n=8) was not treated. Tissue samples were taken from the left and right vastus lateralis before and after the HBO treatment period, respectively, for all rats in both groups. Levels of adenosine monophosphate (AMP), adenosine diphosphate, andenosine triphosphate (ATP) and xanthine oxidase in the muscle tissue were determined. HBO treatment caused a statistically significant increase in ATP (p=0.001) and decrease in AMP (p=0.02) in the HBO-treated group, while there were no significant differences in metabolites in the control group. These results suggest that HBO treatment induces an increase in the ATP levels of muscle tissue with normal mitochondria. Thus, HBO might have some beneficial effects in the treatment of heteroplasmic mitochondrial disease, where normal and defective mitochondria coexist.
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Affiliation(s)
- Bülent Kurt
- Department of Pathology, Gulhane Military Medical Academy and Medical School, Etlik, Ankara, Turkey.
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Paintlia MK, Paintlia AS, Khan M, Singh I, Singh AK. Modulation of peroxisome proliferator-activated receptor-alpha activity by N-acetyl cysteine attenuates inhibition of oligodendrocyte development in lipopolysaccharide stimulated mixed glial cultures. J Neurochem 2008; 105:956-70. [PMID: 18205750 DOI: 10.1111/j.1471-4159.2007.05199.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glial cells secrete proinflammatory mediators in the brain in response to exogenous stimuli such as infection and injury. Previously, we documented that systemic maternal lipopolysaccharide (LPS)-exposure at embryonic gestation day 18 causes oligodendrocyte (OL)-injury/hypomyelination in the developing brain which can be attenuated by N-acetyl cysteine (NAC; precursor of glutathione). The present study delineates the underlying mechanism of NAC-mediated attenuation of inhibition of OL development in LPS-stimulated mixed glial cultures. Factors released by LPS-stimulated mixed glial cultures inhibited OL development as shown by decrease in both proliferation 3bromo-deoxyuridine+/chondroitin sulfate proteoglycan-NG2+, hereafter BrdU+/NG+ and differentiation (O4+ and myelin basic protein+) of OL-progenitors. Correspondingly, an impairment of peroxisomal proliferation was shown by a decrease in the level of peroxisomal proteins in the developing OLs following exposure to LPS-conditioned media (LCM). Both NAC and WY14643, a peroxisome proliferator-activated receptor (PPAR)-alpha agonist attenuated these LCM-induced effects in OL-progenitors. Similar to WY14643, NAC attenuated LCM-induced inhibition of PPAR-alpha activity in developing OLs. Studies conducted with cytokines and diamide (a thiol-depleting agent) confirmed that cytokines are active agents in LCM which may be responsible for inhibition of OL development via peroxisomal dysfunction and induction of oxidative stress. These findings were further corroborated by similar treatment of developing OLs generated from PPAR-alpha(-/-) and wild-type mice or B12 oligodendroglial cells co-transfected with PPAR-alpha small interfering RNAs/pTK-PPREx3-Luc plasmids. Collectively, these data provide evidence that the modulation of PPAR-alpha activity, thus peroxisomal function by NAC attenuates LPS-induced glial factors-mediated inhibition of OL development suggesting new therapeutic interventions to prevent the devastating effects of maternal infections.
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Affiliation(s)
- Manjeet K Paintlia
- Department of Pediatrics, Medical University of South Carolina and Ralph H. Johnson VA Medical Center, Charleston, South Carolina 29425, USA
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Paintlia MK, Paintlia AS, Contreras MA, Singh I, Singh AK. Lipopolysaccharide-induced peroxisomal dysfunction exacerbates cerebral white matter injury: attenuation by N-acetyl cysteine. Exp Neurol 2007; 210:560-76. [PMID: 18291369 DOI: 10.1016/j.expneurol.2007.12.011] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 11/20/2007] [Accepted: 12/04/2007] [Indexed: 01/05/2023]
Abstract
Cerebral white matter injury during prenatal maternal infection characterized as periventricular leukomalacia is the main substrate for cerebral palsy (CP) in premature infants. Previously, we reported that maternal LPS exposure causes oligodendrocyte (OL)-injury/hypomyelination in the developing brain which can be attenuated by an antioxidant agent, N-acetyl cysteine (NAC). Herein, we elucidated the role of peroxisomes in LPS-induced neuroinflammation and cerebral white matter injury. Peroxisomes are important for detoxification of reactive oxidative species (ROS) and metabolism of myelin-lipids in OLs. Maternal LPS exposure induced selective depletion of developing OLs in the fetal brain which was associated with ROS generation, glutathione depletion and peroxisomal dysfunction. Likewise, hypomyelination in the postnatal brain was associated with decrease in peroxisomes and OLs after maternal LPS exposure. Conversely, NAC abolished these LPS-induced effects in the developing brain. CP brains imitated these observed changes in peroxisomal/myelin proteins in the postnatal brain after maternal LPS exposure. In vitro studies revealed that pro-inflammatory cytokines cause OL-injury via peroxisomal dysfunction and ROS generation. NAC or WY14643 (peroxisome proliferators activated receptor (PPAR)-alpha agonist) reverses these effects of pro-inflammatory cytokines in the wild-type OLs, but not in PPAR-alpha(-/-) OLs. Similarly treated B12 oligodenroglial cells co-transfected with PPAR-alpha siRNAs/pTK-PPREx3-Luc, and LPS exposed PPAR-alpha(-/-) pregnant mice treated with NAC or WY14643 further suggested that PPAR-alpha activity mediates NAC-induced protective effects. Collectively, these data provide unprecedented evidence that LPS-induced peroxisomal dysfunction exacerbates cerebral white matter injury and its attenuation by NAC via a PPAR-alpha dependent mechanism expands therapeutic avenues for CP and related demyelinating diseases.
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Affiliation(s)
- Manjeet K Paintlia
- Department of Pediatrics, Medical University of South Carolina, Charleston, SC 29425, USA
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Korkmaz A, Oter S, Sadir S, Topal T, Uysal B, Ozler M, Ay H, Akin A. Exposure time related oxidative action of hyperbaric oxygen in rat brain. Neurochem Res 2007; 33:160-6. [PMID: 17710543 DOI: 10.1007/s11064-007-9428-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Accepted: 06/26/2007] [Indexed: 12/21/2022]
Abstract
Hyperbaric oxygen (HBO) is known to cause oxidative stress in several organs and tissues. Due to its high rate of blood flow and oxygen consumption, the brain is one of the most sensitive organs to this effect. The present study was performed to elucidate the relation of HBO exposure time to its oxidative effects in rats' brain cortex tissue. For this purpose, 49 rats were randomly divided into five groups. Except the control group, study groups were subjected to three atmospheres HBO for 30, 60, 90, and 120 min. Their cerebral cortex layer was taken immediately after exposure and used for analysis. Thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and nitrate-nitrite (NOX) levels were determined. TBARS and SOD levels were found to increase in a time-dependent manner. GSH-Px activity reflected an inconsistent course. NOX levels were found to be increased only in the 120 min exposed group. The results of this study suggests that HBO induced oxidative effects are strongly related with exposure time.
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Affiliation(s)
- Ahmet Korkmaz
- Department of Physiology, Gülhane Askeri Tip Akademisi, Fizyoloji Anabilim Dali, 06018 Ankara, Turkey
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Ay H, Topal T, Uysal B, Ozler M, Oter S, Korkmaz A, Dündar K. Time-dependent course of hyperbaric oxygen-induced oxidative effects in rat lung and erythrocytes. Clin Exp Pharmacol Physiol 2007; 34:787-91. [PMID: 17600558 DOI: 10.1111/j.1440-1681.2007.04645.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
1. The oxygen toxicity of hyperbaric oxygen (HBO) treatment has long been of interest. There is an extensive amount of information regarding the role oxidative stress plays after HBO exposure in different tissues, but the question of the persistence of this oxidative effect has not been thoroughly elucidated. 2. The present study was performed to elucidate the persistence of the oxidative effects of HBO on rat lungs and erythrocytes after they had been subjected to 100% oxygen exposure. 3. Rats were divided into five groups. All animals, except those in the control group, were subjected to 100% oxygen for 2 h at 3 ATA ( identical with 300 kPa). Rats were killed at 30, 60, 90 or 120 min after exposure and thiobarbituric acid-reactive substances (TBARS) levels and the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were determined. 4. Thiobarbituric acid-reactive substances levels and SOD and GPx levels were found to be significantly increased in lung tissue up to 60 min after exposure. Superoxide dismutase activity persisted at significantly high values for 90 min after exposure in erythrocytes and the lung. The TBARS levels in erythrocytes were also significantly higher for 60 min, whereas increased GPx activity was observed to persist for only 30 min. 5. The oxidative effect of HBO exposure declines to physiological levels within 90 min at most for erythrocytes and in lung tissue in rats. Further studies should focus on the molecular mechanisms that can be activated during this time interval.
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Affiliation(s)
- Hakan Ay
- Department of Undersea and Hyperbaric Medicine, Gülhane Military Medical Academy, Ankara, Turkey
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Ay H, Topal T, Ozler M, Uysal B, Korkmaz A, Oter S, Ogur R, Dündar K. Persistence of hyperbaric oxygen-induced oxidative effects after exposure in rat brain cortex tissue. Life Sci 2007; 80:2025-9. [PMID: 17407783 DOI: 10.1016/j.lfs.2007.03.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2006] [Revised: 02/11/2007] [Accepted: 03/05/2007] [Indexed: 10/23/2022]
Abstract
Hyperbaric oxygen (HBO) causes oxidative stress in several organs and tissues. Due to its high rate of blood flow and oxygen consumption, the brain is one of the most sensitive organs to this effect. Many studies have reported oxidative effects of HBO, but there is no comprehensive data about how long this effect persists. The aim of this study was to elucidate the duration of HBO-induced oxidative/antioxidant action. Male Sprague-Dawley rats were divided into 5 groups. Except for the controls, the animals were subjected to 100% oxygen for 2 h at 3 atm and differed from each other by the time to dissection after exposure that began at 30, 60, 90, or 120 min. Thiobarbituric acid-reactive substances (TBARS), as well as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity was determined in brain cortex tissue. Additionally, nitrite-nitrate (NO(x)) concentrations were measured. All measured parameters were found to be significantly increased 30 min after exposure. SOD and GSH-Px levels persisted at significantly high levels for 60 min. In conclusion, the oxidative effect of HBO was shown to persist only for 1 h. Further studies should be performed to elucidate the possible molecular interactions during this period.
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Affiliation(s)
- Hakan Ay
- Department of Undersea and Hyperbaric Medicine, Gülhane Military Medical Academy, 06018 - Etlik/Ankara, Turkey
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Mollaoglu H, Topal T, Ozler M, Uysal B, Reiter RJ, Korkmaz A, Oter S. Antioxidant effects of melatonin in rats during chronic exposure to hyperbaric oxygen. J Pineal Res 2007; 42:50-4. [PMID: 17198538 DOI: 10.1111/j.1600-079x.2006.00382.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In addition to its beneficial effects, hyperbaric oxygen (HBO) exposure causes some detrimental effects via oxidative stress. Previous experimental studies showed that melatonin is a useful agent to block single session HBO-induced oxidative stress. In the present study, we investigated the antioxidant effect of exogenously administered as well as endogenously produced melatonin in lung and brain tissues of rats exposed to long term HBO. The HBO procedure was set as daily exposures to 2.5 ATA of oxygen for 1 hr and a total of 10 sessions. Twenty-eight male Sprague-Dawley rats were divided into four groups as follows: control, daytime HBO, daytime HBO plus melatonin (5 mg/kg), nighttime HBO. Tissue oxidative/antioxidant status was examined by determining the protein carbonyl content as a criteria for oxidative stress and the activities of the antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). HBO exposure for 10 days caused significant increases in protein carbonyl content and SOD levels of lung and brain, but GSH-Px activities remained unaffected. The increases in protein carbonyls were blocked by exogenously administered melatonin and in part by nighttime exposure to darkness whereas the increase of SOD activity was only impeded by endogenously produced melatonin in brain tissue. Lung SOD activity was augmented by endogenous melatonin. In conclusion, melatonin blocks long-term HBO-induced cumulative oxidative stress as indicated changes in protein carbonyls. Both exogenously injected and physiologically secreted melatonin has this potential. The effects of HBO-exposure and melatonin on the activities of the antioxidative enzymes are less clear.
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Affiliation(s)
- Hakan Mollaoglu
- Department of Physiology, Afyon Kocatepe University School of Medicine, Afyon, Turkey.
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. AAAY. Protection Effects of Carvedilol Against Stress-induced Oxidative Damage in Rats Brain. JOURNAL OF MEDICAL SCIENCES 2006. [DOI: 10.3923/jms.2006.554.560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Etlik Ö, Tomur A. THE OXIDANT EFFECTS OF HYPERBARIC OXYGENATION AND AIR POLLUTION IN ERYTHROCYTE MEMBRANES (HYPERBARIC OXYGENATION IN AIR POLLUTION). ELECTRONIC JOURNAL OF GENERAL MEDICINE 2006. [DOI: 10.29333/ejgm/82356] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Smith AM, Zeve DR, Grisel JJ, Chen WJA. Neonatal alcohol exposure increases malondialdehyde (MDA) and glutathione (GSH) levels in the developing cerebellum. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2005; 160:231-8. [PMID: 16256207 DOI: 10.1016/j.devbrainres.2005.09.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2005] [Revised: 09/05/2005] [Accepted: 09/16/2005] [Indexed: 11/30/2022]
Abstract
It has been suggested that developmental alcohol-induced brain damage is mediated through increases in oxidative stress. In this study, the concentrations of malondialdehyde (MDA) and reduced glutathione (GSH) were measured to indicate alcohol-mediated oxidative stress. In addition, the ability of two known antioxidants, melatonin (MEL) and lazaroid U-83836E (U), to attenuate alcohol-induced oxidative stress was investigated. Sprague-Dawley rat pups were randomly assigned to six artificially-reared groups, ALC (alcohol), MEL, MEL/ALC, U, U/ALC, and GC (gastrostomy control), and one normal suckle control (to control for artificial-rearing effects on the dependent variables). The daily dosages for ALC, MEL, and U were 6 g/kg, 20 mg/kg, and 20 mg/kg, respectively. Alcohol was administered in 2 consecutive feedings, and antioxidant (MEL or U) was administered for a total of 4 consecutive feedings (2 feedings prior to and 2 feedings concurrently with alcohol). The animals received treatment from postnatal days (PD) 4 through 9. Cerebellar, hippocampal, and cortical samples were collected on PD 9 and analyzed for MDA and GSH content. The results indicated that MDA concentrations in the cerebellum were significantly elevated in animals receiving alcohol; however, MDA levels in the hippocampus and cortex were not affected by alcohol treatment. Additionally, GSH levels in the cerebellum were significantly elevated in groups receiving alcohol, regardless of antioxidant treatment. Neither antioxidant was able to protect against alcohol-induced alterations of MDA or GSH. These findings suggest that alcohol might increase GSH levels indirectly as a compensatory mechanism designed to protect the brain from oxidative-stress-mediated insult.
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Affiliation(s)
- Andrew M Smith
- 142E Reynolds Medical Building, Department of Human Anatomy and Medical Neurobiology, College of Medicine, The Texas A&M University System Health Science Center, College Station, TX 77843-1114, USA
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Oter S, Korkmaz A, Topal T, Ozcan O, Sadir S, Ozler M, Ogur R, Bilgic H. Correlation between hyperbaric oxygen exposure pressures and oxidative parameters in rat lung, brain, and erythrocytes. Clin Biochem 2005; 38:706-11. [PMID: 15904909 DOI: 10.1016/j.clinbiochem.2005.04.005] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2004] [Revised: 03/20/2005] [Accepted: 04/13/2005] [Indexed: 10/25/2022]
Abstract
OBJECTIVES The oxygen toxicity risk of hyperbaric oxygen (HBO) treatment has long been of interest. However, there are no comprehensive articles describing the relationship between HBO protocols and oxidative parameters used clinically. The purpose of this study was to determine the effects of various HBO pressure modalities on the oxidative values of rat lung, brain, and erythrocytes. DESIGN AND METHODS A total of 64 male Sprague-Dawley rats was randomly divided into 7 groups. Group A was used as a control. Groups C to G were subjected to 100% oxygen at a pressure of 1, 1.5, 2, 2.5, and 3 ATA (atmosphere absolute), respectively, for 2 h. Group B was exposed to normal atmospheric air at 3 ATA for the same duration. The rat's lung, brain, and blood were taken immediately after the exposure and thiobarbituric acid reactive substances (TBARS) and superoxide dismutase (SOD) levels were determined. RESULTS Both TBARS levels and SOD activity increased concordantly with the pressure increase. Although a statistically significant change in TBARS levels started from 100% oxygen exposure at 1 ATA (normobaric), SOD activity was affected after 2 ATA. A significant correlation exists between exposure pressure and the aforementioned parameters. Ambient air exposure at 3 ATA did not affect any parameters besides the brain TBARS levels. CONCLUSIONS It is clear that HBO exposure causes oxidative stress. The main reason for this effect seems to be exposure to pure oxygen, since pure high pressure has no significant effect on the aforementioned parameters. However, clinicians should use as low pressures as possible since all oxidative parameters appear to be directly proportional to the extent of HBO exposure.
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Affiliation(s)
- Sukru Oter
- Gülhane Military Medical Academy, Department of Physiology, GATA-Fizyoloji Anabilim Dali, 06018-Etlik Ankara, Turkey.
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Dundar K, Topal T, Ay H, Oter S, Korkmaz A. Protective effects of exogenously administered or endogenously produced melatonin on hyperbaric oxygen-induced oxidative stress in the rat brain. Clin Exp Pharmacol Physiol 2005; 32:926-30. [PMID: 16405448 DOI: 10.1111/j.1440-1681.2005.04286.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1. Hyperbaric oxygen (HBO) is a widely used treatment modality in many diseases. A known side-effect of HBO is the production of reactive oxygen species (ROS). Many anti-oxidants, such as vitamins C and E, riboflavin and selenium, have been used successfully to scavenge the ROS produced by HBO administration. 2. The aim of the present study was to determine whether melatonin, a newly discovered anti-oxidant, has a protective effect against the overproduction of ROS produced by HBO in rat brain tissue. 3. Seventy male Sprague-Dawley rats were divided into seven groups as follows: 1, daytime control; 2, daytime HBO; 3, melatonin; 4, daytime HBO plus melatonin; 5, night-time control; 6, night-time HBO; and 7, night-time HBO under light exposure. 4. Hyperbaric oxygen was administered at 303 kPa for 120 min. Melatonin was injected at a dose of 10 mg/kg, i.p. Brain malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels were measured to elucidate oxidant status. 4. The MDA and SOD levels of groups 2 and 7 increased significantly. Exogenous (group 4) and endogenous (group 6) melatonin protected against HBO-induced lipid peroxidation. Exogenously administered melatonin (groups 3 and 4) had increased levels of the anti-oxidant enzymes SOD and GPx. 5. In conclusion, HBO caused oxidative stress and melatonin exhibited protective effects. Both endogenously produced and exogenously administered melatonin were found to be effective.
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Affiliation(s)
- Kadir Dundar
- Department of Undersea and Hyperbaric Medicine, Gulhane Military Medical Academy, Ankara, Turkey
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Oter S, Edremitlioglu M, Korkmaz A, Coskun O, Kilic D, Kisa U, Yaren H, Bilgic H. Effects of hyperbaric oxygen treatment on liver functions, oxidative status and histology in septic rats. Intensive Care Med 2005; 31:1262-8. [PMID: 16034622 DOI: 10.1007/s00134-005-2701-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2005] [Accepted: 05/27/2005] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The liver is thought to be responsible for multiple organ failure during sepsis. Increase in tissue oxygen consumption is a major component of the septic response. Hyperbaric oxygen (HBO) therapy provides more oxygenation in the whole body. This study examined the effect of HBO alone or in combination with cefepime (CEF) on the liver in septic rats. DESIGN AND INTERVENTIONS We divided 90 male rats into six groups; control, HBO, sepsis (SEP), SEP+HBO, SEP+CEF, and SEP+CEF+HBO. Sepsis was induced with an intraperitoneal injection of Escherichia coli (2.1 x 10(9) cfu). A total of six HBO sessions were performed at 2 atm absolute for 90 min at 6-h intervals. CEF was administered intraperitoneally at a dose of 50 mg/kg twice daily. Animals were killed 48 h after sepsis induction. Their liver and blood were removed for biochemical and histopathological analysis. MEASUREMENTS AND RESULTS Liver thiobarbituric acid reactive substances as well as serum alanine transaminase, aspartate transaminase and alkaline phosphatase levels increased while the activity of the antioxidant enzymes superoxide dismutase and catalase decreased significantly in septic rats. These parameters returned to nearly control levels in the SEP+CEF+HBO group. Histological observations supported these findings: Hepatocellular degeneration was observed and intensive polymorphonuclear cell infiltration appeared in all fields of septic animal livers. HBO alone could not sufficiently reverse these histopathological changes, but most liver sections presented normal histology when it was combined with CEF. CONCLUSIONS HBO may be a useful adjuvant therapy modality to improve the efficacy of sepsis treatment.
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Affiliation(s)
- Sukru Oter
- Department of Physiology, Gulhane Military Medical Academy, Etlik, 06018 Ankara, Turkey.
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Ozcan A, Korkmaz A, Oter S, Coskun O. Contribution of flavonoid antioxidants to the preventive effect of mesna in cyclophosphamide-induced cystitis in rats. Arch Toxicol 2005; 79:461-5. [PMID: 15800758 DOI: 10.1007/s00204-005-0647-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Accepted: 12/23/2004] [Indexed: 11/26/2022]
Abstract
Cyclophosphamide (CP) is widely used, alone or in combination with other chemotherapeutic agents, for treatment of neoplastic diseases. Its urotoxicity may cause dose-limiting side-effects, for example hemorrhagic cystitis. The agent most often used to prevent this side-effect is mesna (2-mercaptoethane sulfonate). Overproduction of reactive oxygen species during inflammation is one reason for possible urothelial injury. The aim of this study was to evaluate whether combinations of quercetin and epigallocatechin 3-gallate (EGCG), flavonoid antioxidants and mesna could prevent cystitis induced by cyclophosphamide, better than mesna alone. A total of 38 male Sprague-Dawley rats were divided into five groups. Four groups received single dose of CP (100 mg kg(-1)) intraperitoneally at the same time. Group 2 received CP only, group 3 received mesna (3 x 21.5 mg kg(-1)), group 4 received a single dose of mesna+EGCG (2 x 20 mg kg(-1)), and group 5 received a single dose of mesna+quercetin (2 x 20 mg kg(-1)), before and after CP injection. Group 1 (not treated) served as control. CP injection alone resulted in severe cystitis. Mesna resulted in some, but not full, protection against CP toxicity. Quercetin and catechine, together with mesna, resulted in full protection against CP toxicity, on the basis of histopathology of the urinary bladder. It was concluded that oxidants might be important in the pathogenesis of CP-induced cystitis, and that flavonoid antioxidants, used in addition to mesna, may help to ameliorate bladder damage.
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Affiliation(s)
- Ayhan Ozcan
- Department of Pathology, Gulhane Military Medical Academy, Ankara, Turkey
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Carrillo-Vico A, Lardone PJ, Fernández-Santos JM, Martín-Lacave I, Calvo JR, Karasek M, Guerrero JM. Human lymphocyte-synthesized melatonin is involved in the regulation of the interleukin-2/interleukin-2 receptor system. J Clin Endocrinol Metab 2005; 90:992-1000. [PMID: 15562014 DOI: 10.1210/jc.2004-1429] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Since melatonin was first isolated in 1958 up to the last few years, this substance was considered a hormone exclusive to the pineal gland. Although melatonin has lately been identified in a large number of extrapineal sites, its potential biological actions have not yet been studied. This paper shows that human lymphocyte-synthesized melatonin plays a crucial role modulating IL-2/IL-2 receptor system because when blocking melatonin biosynthesis by the tryptophan hydroxylase inhibitor, parachlorophenylalanine, both IL-2 and IL-2 receptor levels fell, restoring them by adding exogenous melatonin. Moreover, we demonstrated that this endogenous melatonin interfered with the exogenous melatonin effect on IL-2 production. Melatonin exerted these effects by a receptor-mediated action mechanism because both IL-2 and IL-2 receptor expressions significantly decreased when lymphocytes were incubated in the presence of the specific membrane and/or nuclear melatonin receptor antagonists, luzindole, and/or CGP 55644, respectively. Finally, we made the real significance of the membrane melatonin receptors in this process clear, so prostaglandin E(2)-induced inhibition on IL-2 production increased when we blocked the membrane receptors using luzindole. In conclusion, these data show that endogenous melatonin is an essential part for an accurate response of human lymphocytes through the modulation of IL-2/IL-2 receptor system.
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Affiliation(s)
- Antonio Carrillo-Vico
- Department of Medical Biochemistry and Molecular Biology, The University of Seville School of Medicine, Avda. Sánchez Pizjuán 4, 41009 Seville, Spain
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