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Hu X, Sun Z, Wang W, Xiao G, Yu Q, Chi L, Liu H. Dexmedetomidine attenuates isoflurane-induced neuroapoptosis through the miR-137/GSK-3β pathway in the developing rat hippocampus. Heliyon 2024; 10:e31372. [PMID: 38813218 PMCID: PMC11133896 DOI: 10.1016/j.heliyon.2024.e31372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 05/11/2024] [Accepted: 05/15/2024] [Indexed: 05/31/2024] Open
Abstract
Long-term isoflurane inhalation has been reported to induce hippocampal apoptosis in young animals, whereas dexmedetomidine (DEX) can reduce isoflurane-induced neuronal apoptosis. The neuroprotective effect of miR-137 has been reported before, however, the effect of on isoflurane triggered neuronal apoptosis, and whether miR-137 is involved in the neuroprotection of DEX remain unclear. To investigate these doubts, we established an isoflurane exposure model in postnatal day 7 (P7) Sprague‒Dawley rats and the PC12 cells, containing a control group (CON), isoflurane group (ISO), DEX group (DEX) and DEX pretreatment group (DEX + ISO). We first confirmed that DEX attenuates isoflurane-induced hippocampal apoptosis. And we found DEX increased miR-137 and attenuated GSK-3β levels in the DEX and DEX + ISO groups in the hippocampus and PC12 cells. In addition, the regulative relationship of miR-137 and GSK-3β was confirmed using the TargetScan tool and dual-luciferase reporter assay. Moreover, miR-137 overexpression inhibited GSK-3β and increased its downstream gene β-catenin, whereas knockdown of miR-137 changed the GSK-3β and β-catenin expression oppositely. Upregulation of miR-137 increased the apoptosis-related genes and decreased the anti-apoptosis gene; however, knockdown of miR-137 produced the opposite results. This study suggested that DEX attenuated isoflurane-induced neuroapoptosis by upregulating the miR-137 mediated GSK-3β/β-catenin pathway in the developing rat hippocampus.
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Affiliation(s)
- Xueyuan Hu
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Zihan Sun
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Wenjing Wang
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Gong Xiao
- Animal Husbandry Development Promotion Center of Pingyi County, Linyi, 273300, China
| | - Quanlin Yu
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Liang Chi
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Huanqi Liu
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China
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Olufs ZPG, Wassarman DA, Perouansky M. Stress Pathways Induced by Volatile Anesthetics and Failure of Preconditioning in a Mitochondrial Complex I Mutant. Anesthesiology 2024; 140:463-482. [PMID: 38118175 DOI: 10.1097/aln.0000000000004874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
BACKGROUND Carriers of mutations in the mitochondrial electron transport chain are at increased risk of anesthetic-induced neurotoxicity. To investigate the neurotoxicity mechanism and to test preconditioning as a protective strategy, this study used a Drosophila melanogaster model of Leigh syndrome. Model flies carried a mutation in ND23 (ND2360114) that encodes a mitochondrial electron transport chain complex I subunit. This study investigated why ND2360114 mutants become susceptible to lethal, oxygen-modulated neurotoxicity within 24 h of exposure to isoflurane but not sevoflurane. METHODS This study used transcriptomics and quantitative real-time reverse transcription polymerase chain reaction to identify genes that are differentially expressed in ND2360114 but not wild-type fly heads at 30 min after exposure to high- versus low-toxicity conditions. This study also subjected ND2360114 flies to diverse stressors before isoflurane exposure to test whether isoflurane toxicity could be diminished by preconditioning. RESULTS The ND2360114 mutation had a greater effect on isoflurane- than sevoflurane-mediated changes in gene expression. Isoflurane and sevoflurane did not affect expression of heat shock protein (Hsp) genes (Hsp22, Hsp27, and Hsp68) in wild-type flies, but isoflurane substantially increased expression of these genes in ND2360114 mutant flies. Furthermore, isoflurane and sevoflurane induced expression of oxidative (GstD1 and GstD2) and xenobiotic (Cyp6a8 and Cyp6a14) stress genes to a similar extent in wild-type flies, but the effect of isoflurane was largely reduced in ND2360114 flies. In addition, activating stress response pathways by pre-exposure to anesthetics, heat shock, hyperoxia, hypoxia, or oxidative stress did not suppress isoflurane-induced toxicity in ND2360114 mutant flies. CONCLUSIONS Mutation of a mitochondrial electron transport chain complex I subunit generates differential effects of isoflurane and sevoflurane on gene expression that may underlie their differential effects on neurotoxicity. Additionally, the mutation produces resistance to preconditioning by stresses that protect the brain in other contexts. Therefore, complex I activity modifies molecular and physiologic effects of anesthetics in an anesthetic-specific manner. EDITOR’S PERSPECTIVE
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Affiliation(s)
- Zachariah P G Olufs
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin
| | - David A Wassarman
- Department of Medical Genetics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin
| | - Misha Perouansky
- Department of Anesthesiology, School of Medicine and Public Health and Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin
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Uryash A, Mijares A, Lopez CE, Adams JA, Allen PD, Lopez JR. Post-Anesthesia Cognitive Dysfunction in Mice Is Associated with an Age-Related Increase in Neuronal Intracellular [Ca 2+]-Neuroprotective Effect of Reducing Intracellular [Ca 2+]: In Vivo and In Vitro Studies. Cells 2024; 13:264. [PMID: 38334656 PMCID: PMC10854970 DOI: 10.3390/cells13030264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 01/21/2024] [Accepted: 01/28/2024] [Indexed: 02/10/2024] Open
Abstract
Background: Postoperative cognitive dysfunction (POCD) is a common disorder after general anesthesia in elderly patients, the precise mechanisms of which remain unclear. Methods: We investigated the effect of isoflurane with or without dantrolene pretreatment on intracellular calcium concentration ([Ca2+]i), reactive oxygen species (ROS) production, cellular lactate dehydrogenase (LDH) leak, calpain activity, and cognitive function using the Morris water maze test of young (3 months), middle-aged (12-13 months), and aged (24-25 months) C57BL6/J mice. Results: Aged cortical and hippocampal neurons showed chronically elevated [Ca2+]i compared to young neurons. Furthermore, aged hippocampal neurons exhibited higher ROS production, increased LDH leak, and elevated calpain activity. Exposure to isoflurane exacerbated these markers in aged neurons, contributing to increased cognitive deficits in aged mice. Dantrolene pretreatment reduced [Ca2+]i for all age groups and prevented or significantly mitigated the effects of isoflurane on [Ca2+]i, ROS production, LDH leak, and calpain activity in aged neurons. Dantrolene also normalized or improved age-associated cognitive deficits and mitigated the cognitive deficits caused by isoflurane. Conclusions: These findings suggest that isoflurane-induced cytotoxicity and cognitive decline in aging are linked to disruptions in neuronal intracellular processes, highlighting the reduction of [Ca2+]i as a potential therapeutic intervention.
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Affiliation(s)
- Arkady Uryash
- Division of Neonatology, Mount Sinai Medical Center, Miami, FL 33140, USA; (A.U.); (J.A.A.)
| | - Alfredo Mijares
- Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Caracas 1020, Venezuela;
| | | | - Jose A. Adams
- Division of Neonatology, Mount Sinai Medical Center, Miami, FL 33140, USA; (A.U.); (J.A.A.)
| | - Paul D. Allen
- Leeds Institute of Biomedical & Clinical Sciences, University of Leeds, Leeds LS9 7TF, UK;
| | - Jose R. Lopez
- Department of Research, Mount Sinai Medical Center, Miami Beach, FL 33140, USA
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Fantalis D, Bordovsky S, Preobrazhenskaya I. Cognitive and emotional disorders in neurosurgical patients and their impact on postoperative rehabilitation. Zh Nevrol Psikhiatr Im S S Korsakova 2022; 122:81-87. [DOI: 10.17116/jnevro202212202181] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
Ferroptosis, an iron-dependent form of programmed cell death, is characterized by iron overload, increased reactive oxygen species (ROS) generation, and depletion of glutathione (GSH) and lipid peroxidation. Lipophilic antioxidants and iron chelators can prevent ferroptosis. GSH-dependent glutathione peroxidase 4 (GPX4) prevents lipid ROS accumulation. Ferroptosis is thought to be initiated through GPX4 inactivation. Moreover, mitochondrial iron overload derived from the degradation of ferritin is involved in increasing ROS generation. Ferroptosis has been suggested to explain the mechanism of action of organ toxicity induced by several drugs and chemicals. Inhibition of ferroptosis may provide novel therapeutic opportunities for treatment and even prevention of such organ toxicities.
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Affiliation(s)
- Fatemeh Yarmohammadi
- Student Research Committee, 37552Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmacodynamics and Toxicology, School of Pharmacy, 37552Mashhad University of Medical Sciences, Mashhad, Iran
| | - A Wallace Hayes
- Center for Environmental Occupational Risk Analysis and Management, College of Public Health, 27117University of South Florida, Tampa, FL, USA.,Institute for Integrative Toxicology, 27117Michigan State University, East Lansing, MI, USA
| | - Gholamreza Karimi
- Department of Pharmacodynamics and Toxicology, School of Pharmacy, 37552Mashhad University of Medical Sciences, Mashhad, Iran.,Pharmaceutical Research Center, Pharmaceutical Technology Institute, 37552Mashhad University of Medical Sciences, Mashhad, Iran
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Khan H, Kashyap A, Kaur A, Singh TG. Pharmacological postconditioning: a molecular aspect in ischemic injury. J Pharm Pharmacol 2020; 72:1513-1527. [PMID: 33460133 DOI: 10.1111/jphp.13336] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 06/21/2020] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Ischaemia/reperfusion (I/R) injury is defined as the damage to the tissue which is caused when blood supply returns to tissue after ischaemia. To protect the ischaemic tissue from irreversible injury, various protective agents have been studied but the benefits have not been clinically applicable due to monotargeting, low potency, late delivery or poor tolerability. KEY FINDINGS Strategies involving preconditioning or postconditioning can address the issues related to the failure of protective therapies. In principle, postconditioning (PoCo) is clinically more applicable in the conditions in which there is unannounced ischaemic event. Moreover, PoCo is an attractive beneficial strategy as it can be induced rapidly at the onset of reperfusion via series of brief I/R cycles following a major ischaemic event or it can be induced in a delayed manner. Various pharmacological postconditioning (pPoCo) mechanisms have been investigated systematically. Using different animal models, most of the studies on pPoCo have been carried out preclinically. SUMMARY However, there is a need for the optimization of the clinical protocols to quicken pPoCo clinical translation for future studies. This review summarizes the involvement of various receptors and signalling pathways in the protective mechanisms of pPoCo.
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Affiliation(s)
- Heena Khan
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Ankita Kashyap
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Amarjot Kaur
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
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Conflicting Actions of Inhalational Anesthetics, Neurotoxicity and Neuroprotection, Mediated by the Unfolded Protein Response. Int J Mol Sci 2020; 21:ijms21020450. [PMID: 31936788 PMCID: PMC7013687 DOI: 10.3390/ijms21020450] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 01/02/2020] [Accepted: 01/08/2020] [Indexed: 12/12/2022] Open
Abstract
Preclinical studies have shown that exposure of the developing brain to inhalational anesthetics can cause neurotoxicity. However, other studies have claimed that anesthetics can exert neuroprotective effects. We investigated the mechanisms associated with the neurotoxic and neuroprotective effects exerted by inhalational anesthetics. Neuroblastoma cells were exposed to sevoflurane and then cultured in 1% oxygen. We evaluated the expression of proteins related to the unfolded protein response (UPR). Next, we exposed adult mice in which binding immunoglobulin protein (BiP) had been mutated, and wild-type mice, to sevoflurane, and evaluated their cognitive function. We compared our results to those from our previous study in which mice were exposed to sevoflurane at the fetal stage. Pre-exposure to sevoflurane reduced the expression of CHOP in neuroblastoma cells exposed to hypoxia. Anesthetic pre-exposure also significantly improved the cognitive function of adult wild-type mice, but not the mutant mice. In contrast, mice exposed to anesthetics during the fetal stage showed cognitive impairment. Our data indicate that exposure to inhalational anesthetics causes endoplasmic reticulum (ER) stress, and subsequently leads to an adaptive response, the UPR. This response may enhance the capacity of cells to adapt to injuries and improve neuronal function in adult mice, but not in developing mice.
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Hypotension and Hypocapnia During General Anesthesia in Piglets: Study of S100b as an Acute Biomarker for Cerebral Tissue Injury. J Neurosurg Anesthesiol 2019; 32:273-278. [DOI: 10.1097/ana.0000000000000601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Finley J. Cellular stress and AMPK links metformin and diverse compounds with accelerated emergence from anesthesia and potential recovery from disorders of consciousness. Med Hypotheses 2019; 124:42-52. [PMID: 30798915 DOI: 10.1016/j.mehy.2019.01.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Accepted: 01/19/2019] [Indexed: 01/23/2023]
Abstract
The neural correlates of consciousness and the mechanisms by which general anesthesia (GA) modulate such correlates to induce loss of consciousness (LOC) has been described as one of the biggest mysteries of modern medicine. Several cellular targets and neural circuits have been identified that play a critical role in LOC induced by GA, including the GABAA receptor and ascending arousal nuclei located in the basal forebrain, hypothalamus, and brain stem. General anesthetics (GAs) including propofol and inhalational agents induce LOC in part by potentiating chloride influx through the GABAA receptor, leading to neural inhibition and LOC. Interestingly, nearly all GAs used clinically may also induce paradoxical excitation, a phenomenon in which GAs promote neuronal excitation at low doses before inducing unconsciousness. Additionally, emergence from GA, a passive process that occurs after anesthetic removal, is associated with lower anesthetic concentrations in the brain compared to doses associated with induction of GA. AMPK, an evolutionarily conserved kinase activated by cellular stress (e.g. increases in calcium [Ca2+] and/or reactive oxygen species [ROS], etc.) increases lifespan and healthspan in several model organisms. AMPK is located throughout the mammalian brain, including in neurons of the thalamus, hypothalamus, and striatum as well as in pyramidal neurons in the hippocampus and cortex. Increases in ROS and Ca2+ play critical roles in neuronal excitation and glutamate, the primary excitatory neurotransmitter in the human brain, activates AMPK in cortical neurons. Nearly every neurotransmitter released from ascending arousal circuits that promote wakefulness, arousal, and consciousness activates AMPK, including acetylcholine, histamine, orexin-A, dopamine, and norepinephrine. Several GAs that are commonly used to induce LOC in human patients also activate AMPK (e.g. propofol, sevoflurane, isoflurane, dexmedetomidine, ketamine, midazolam). Various compounds that accelerate emergence from anesthesia, thus mitigating problematic effects associated with delayed emergence such as delirium, also activate AMPK (e.g. nicotine, caffeine, forskolin, carbachol). GAs and neurotransmitters also act as preconditioning agents and the GABAA receptor inhibitor bicuculline, which reverses propofol anesthesia, also activates AMPK in cortical neurons. We propose the novel hypothesis that cellular stress-induced AMPK activation links wakefulness, arousal, and consciousness with paradoxical excitation and accelerated emergence from anesthesia. Because AMPK activators including metformin and nicotine promote proliferation and differentiation of neural stem cells located in the subventricular zone and the dentate gyrus, AMPK activation may also enhance brain repair and promote potential recovery from disorders of consciousness (i.e. minimally conscious state, vegetative state, coma).
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10
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Zhu M, Li M, Zhou Y, Dangelmajer S, Kahlert UD, Xie R, Xi Q, Shahveranov A, Ye D, Lei T. Isoflurane enhances the malignant potential of glioblastoma stem cells by promoting their viability, mobility in vitro and migratory capacity in vivo. Br J Anaesth 2018; 116:870-7. [PMID: 27199319 DOI: 10.1093/bja/aew124] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/15/2016] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Isoflurane is one of the most common general anaesthetics used during surgical procedures, including tumour resection. However, the effects of isoflurane on the viability and migration capacity of cancer cells, specifically in the context of brain cancer cells, remain unclear. Therefore, the aim of this study was to evaluate the influence that isoflurane has on the function of glioblastoma stem cells (GCSs) in regards to cell proliferation, survival and migration. METHOD U251-GSCs were exposed to isoflurane at clinically relevant concentrations and incubation times. The effects on proliferation, survival and migration capacities of the cells were evaluated in vitro. The potential risk was assessed in mice by intracranial injection of U251-GSCs pretreated with isoflurane. Furthermore, the average tumour volume and migration distance of U251-GSCs from the tumour centre were calculated. RESULTS Exposure of U251-GSCs to 1.2% isoflurane for 6 h resulted in increased proliferation (P<0.05) and decreased apoptosis rate (P<0.05) when compared with the control group. In addition, isoflurane exposure caused increased migration capacity in vitro (P<0.05) and the distance migrated was increased in vivo (P<0.05). CONCLUSION Clinically relevant concentrations and incubation times of isoflurane could promote the viability and mobility of U251-GSCs, suggesting this general anaesthetic may have detrimental effects in glioblastoma by facilitating its growth and migration.
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Affiliation(s)
- M Zhu
- Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei, People's Republic of China
| | - M Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei, People's Republic of China
| | - Y Zhou
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei, People's Republic of China
| | - S Dangelmajer
- Stanford University School of Medicine, Palo Alto, CA, USA
| | - U D Kahlert
- Department of Pathology, Division of Neuropathology, Johns Hopkins Medical Institutions, Baltimore, MD, USA Department of Neurosurgery, University Medical Center Düsseldorf, Düsseldorf, Germany
| | - R Xie
- Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei, People's Republic of China
| | - Q Xi
- Cancer Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei, People's Republic of China
| | - A Shahveranov
- Cancer Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei, People's Republic of China
| | - D Ye
- Cancer Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei, People's Republic of China
| | - T Lei
- Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei, People's Republic of China
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Absence of Neuropathology With Prolonged Isoflurane Sedation in Healthy Adult Rats. J Neurosurg Anesthesiol 2018; 29:439-447. [PMID: 27653221 DOI: 10.1097/ana.0000000000000365] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The use of isoflurane sedation for prolonged periods in the critical care environment is increasing. However, isoflurane-mediated neurotoxicity has been widely reported. The goal of the present study was to determine whether long-term exposure to low-dose isoflurane in mechanically ventilated rodents is associated with evidence of neurodegeneration or neuroinflammation. METHODS Adult female Sprague-Dawley rats were used in this study. Experimental animals (n=11) were induced with 1.5% isoflurane, intubated, and given a neuromuscular blockade with α-cobratoxin. EEG electrodes were surgically implanted, subcutaneous precordial EKG Ag wire electrodes, and bladder, femoral artery, and femoral vein cannulas permanently placed. After these procedures, the isoflurane concentration was reduced to 0.5% and, in conjunction with the neuromuscular blockade, continued for 7 days. Arterial blood gases and chemistry were measured at 3 time points and core body temperature servoregulated and maintenance IV fluids were given during the 7 days. Experimental animals and untreated controls (n=9) were euthanized on day 7. RESULTS Immunohistochemical and cytochemical assays did not detect evidence of microgliosis, astrocytosis, neuronal apoptosis or necrosis, amyloidosis, or phosphorylated-tau accumulation. Blood glucose levels were significantly reduced on days 3/4 and 6/7 and partial pressure of oxygen was significantly reduced, but still within the normal range, on day 6/7. All other blood measurements were unchanged. CONCLUSIONS No neuropathologic changes consistent with neurotoxicity were detected in the brain after 1 week of continuous exposure to 0.5% isoflurane in healthy rats. These data suggest that even long exposures to low concentrations of isoflurane have no overt consequences on neuropathology.
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Effects of short-term exposure to sevoflurane on the survival, proliferation, apoptosis, and differentiation of neural precursor cells derived from human embryonic stem cells. J Anesth 2017; 31:821-828. [DOI: 10.1007/s00540-017-2408-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 08/09/2017] [Indexed: 12/11/2022]
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Li C, Dong Y, Chen D, Xie Z, Zhang Y. Mild Hypothermia Attenuates the Anesthetic Isoflurane-Induced Cytotoxicity. Front Cell Neurosci 2017; 11:15. [PMID: 28228717 PMCID: PMC5296297 DOI: 10.3389/fncel.2017.00015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 01/18/2017] [Indexed: 02/05/2023] Open
Abstract
The commonly used inhalation anesthetic isoflurane has been reported to induce DNA damage and cytotoxicity. However, the methods to attenuate these effects remain largely to be determined. Mild hypothermia has neuroprotective effects. We therefore set out to assess whether mild hypothermia could protect the isoflurane-induced DNA damage and cytotoxicity. Moreover, we investigated the underlying mechanisms by assessing the effects of mild hypothermia on the isoflurane-induced changes in ATP levels. H4 human neuroglioma cells were treated with 2% isoflurane for 3 or 6 h with and without mild hypothermia (35°C). We assessed the cell viability by using 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) and lactate dehydrogenase (LDH) assay. We determined DNA damage by measuring levels of phosphorylation of the histone protein H2A variant X at Ser139 (γH2A.X), the marker of DNA damage. We also measured ATP levels in the cells. Here we showed that the treatment with 2% isoflurane for 6 h induced cytotoxicity and DNA damage in the cells. Moreover, the treatment with 2% isoflurane for 3 h decreased ATP levels without inducing cytotoxicity. Mild hypothermia attenuated the isoflurane-induced cytotoxicity, DNA damage, and ATP reduction in the cells. Taken together, these data suggest that the isoflurane-induced reduction in ATP levels occurred before the isoflurane-induced cytotoxicity. Isoflurane may induce DNA damage and cause cytotoxicity through reducing ATP levels. Mild hypothermia would ameliorate isoflurane-induced DNA damage and cytotoxicity by attenuating the isoflurane-induced reduction in ATP levels. These pilot studies have established a system and will promote the future investigations of anesthesia neurotoxicity.
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Affiliation(s)
- Cheng Li
- Shanghai Tenth People's Hospital, Tongji University School of MedicineShanghai, China; Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical SchoolCharlestown, MA, USA
| | - Yuanlin Dong
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School Charlestown, MA, USA
| | - Dan Chen
- Shanghai Tenth People's Hospital, Tongji University School of MedicineShanghai, China; Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical SchoolCharlestown, MA, USA
| | - Zhongcong Xie
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School Charlestown, MA, USA
| | - Yiying Zhang
- Shanghai Tenth People's Hospital, Tongji University School of MedicineShanghai, China; Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical SchoolCharlestown, MA, USA
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Neuroprotection and neurotoxicity in the developing brain: an update on the effects of dexmedetomidine and xenon. Neurotoxicol Teratol 2017; 60:102-116. [PMID: 28065636 DOI: 10.1016/j.ntt.2017.01.001] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 12/30/2016] [Accepted: 01/04/2017] [Indexed: 12/13/2022]
Abstract
Growing and consistent preclinical evidence, combined with early clinical epidemiological observations, suggest potentially neurotoxic effects of commonly used anesthetic agents in the developing brain. This has prompted the FDA to issue a safety warning for all sedatives and anesthetics approved for use in children under three years of age. Recent studies have identified dexmedetomidine, the potent α2-adrenoceptor agonist, and xenon, the noble gas, as effective anesthetic adjuvants that are both less neurotoxic to the developing brain, and also possess neuroprotective properties in neonatal and other settings of acute ongoing neurologic injury. Dexmedetomidine and xenon are effective anesthetic adjuvants that appear to be less neurotoxic than other existing agents and have the potential to be neuroprotective in the neonatal and pediatric settings. Although results from recent clinical trials and case reports have indicated the neuroprotective potential of xenon and dexmedetomidine, additional randomized clinical trials corroborating these studies are necessary. By reviewing both the existing preclinical and clinical evidence on the neuroprotective effects of dexmedetomidine and xenon, we hope to provide insight into the potential clinical efficacy of these agents in the management of pediatric surgical patients.
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J. K, Durga P, Ramachandran G. Inhalational agents in anesthesia induced developmental neurotoxicity – Recent advances. TRENDS IN ANAESTHESIA AND CRITICAL CARE 2016. [DOI: 10.1016/j.tacc.2016.10.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Lin EP, Lee JR, Lee CS, Deng M, Loepke AW. Do anesthetics harm the developing human brain? An integrative analysis of animal and human studies. Neurotoxicol Teratol 2016; 60:117-128. [PMID: 27793659 DOI: 10.1016/j.ntt.2016.10.008] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/09/2016] [Accepted: 10/24/2016] [Indexed: 11/28/2022]
Abstract
Anesthetics that permit surgical procedures and stressful interventions have been found to cause structural brain abnormalities and functional impairment in immature animals, generating extensive concerns among clinicians, parents, and government regulators regarding the safe use of these drugs in young children. Critically important questions remain, such as the exact age at which the developing brain is most vulnerable to the effects of anesthetic exposure, whether a particular age exists beyond which anesthetics are devoid of long-term effects on the brain, and whether any specific exposure duration exists that does not lead to deleterious effects. Accordingly, the present analysis attempts to put the growing body of animal studies, which we identified to include >440 laboratory studies to date, into a translational context, by integrating the preclinical data on brain structure and function with clinical results attained from human neurocognitive studies, which currently exceed 30 studies. Our analysis demonstrated no clear exposure duration threshold below which no structural injury or subsequent cognitive abnormalities occurred. Animal data did not clearly identify a specific age beyond which anesthetic exposure did not cause any structural or functional abnormalities. Several potential mitigating strategies were found, however, no general anesthetic was identified that consistently lacked neurodegenerative properties and could be recommended over other anesthetics. It therefore is imperative, to expand efforts to devise safer anesthetic techniques and mitigating strategies, even before long-term alterations in brain development are unequivocally confirmed to occur in millions of young children undergoing anesthesia every year.
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Affiliation(s)
- Erica P Lin
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, United States; Department of Anesthesiology and Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, United States
| | - Jeong-Rim Lee
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, United States; Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea
| | - Christopher S Lee
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, United States; Department of Anesthesiology and Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, United States
| | - Meng Deng
- Department of Anesthesiology, Huashan Hospital of Fudan University, Shanghai, China
| | - Andreas W Loepke
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, United States; Department of Anesthesiology and Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, United States; Neuroscience Program, University of Cincinnati, Cincinnati, OH 45267, United States.
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Levy RJ. Carbon monoxide and anesthesia-induced neurotoxicity. Neurotoxicol Teratol 2016; 60:50-58. [PMID: 27616667 DOI: 10.1016/j.ntt.2016.09.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Revised: 08/10/2016] [Accepted: 09/06/2016] [Indexed: 10/21/2022]
Abstract
The majority of commonly used anesthetic agents induce widespread neuronal degeneration in the developing mammalian brain. Downstream, the process appears to involve activation of the oxidative stress-associated mitochondrial apoptosis pathway. Targeting this pathway could result in prevention of anesthetic toxicity in the immature brain. Carbon monoxide (CO) is a gas that exerts biological activity in the developing brain and low dose exposures have the potential to provide neuroprotection. In recent work, low concentration CO exposures limited isoflurane-induced neuronal apoptosis in a dose-dependent manner in newborn mice and modulated oxidative stress within forebrain mitochondria. Because infants and children are routinely exposed to low levels of CO during low-flow general endotracheal anesthesia, such anti-oxidant and pro-survival cellular effects are clinically relevant. Here we provide an overview of anesthesia-related CO exposure, discuss the biological activity of low concentration CO, detail the effects of CO in the brain during development, and provide evidence for CO-mediated inhibition of anesthesia-induced neurotoxicity.
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Affiliation(s)
- Richard J Levy
- Department of Anesthesiology, Columbia University Medical Center, United States.
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Ni C, Li C, Dong Y, Guo X, Zhang Y, Xie Z. Anesthetic Isoflurane Induces DNA Damage Through Oxidative Stress and p53 Pathway. Mol Neurobiol 2016; 54:3591-3605. [PMID: 27194299 DOI: 10.1007/s12035-016-9937-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Accepted: 05/10/2016] [Indexed: 02/05/2023]
Abstract
DNA damage is associated with aging and neurological disorders, including Alzheimer's disease. Isoflurane is a commonly used anesthetic. It remains largely unknown whether isoflurane induces DNA damage. Phosphorylation of the histone protein H2A variant X at Ser139 (γH2A.X) is a marker of DNA damage. We therefore set out to assess the effects of isoflurane on γH2A.X level in H4 human neuroglioma cells and in brain tissues of mice. Oxidative stress, caspase-activated DNase (CAD), and the p53 signaling pathway are involved in DNA damage. Thus, we determined the interaction of isoflurane with reactive oxygen species (ROS), CAD, and p53 to illustrate the underlying mechanisms. The cells were treated with 2 % isoflurane for 3 or 6 h. The mice were anesthetized with 1.4 % isoflurane for 2 h. Western blot, immunostaining and live cell fluorescence staining were used in the experiments. We showed that isoflurane increased levels of γH2A.X, cleaved caspase-3, and nucleus translocation of CAD and decreased levels of inhibitor of CAD (ICAD) and p53. Isoflurane enhanced the nucleus level of γH2A.X. Moreover, caspase inhibitor Z-VAD and ROS generation inhibitor N-acetyl-L-cysteine (NAC) attenuated the isoflurane-induced increase in γH2A.X level. However, NAC did not significantly alter the isoflurane-induced reduction in p53 level. Finally, p53 activator (actinomycin D) and inhibitor (pifithrin-α) attenuated and potentiated the isoflurane-induced increase in γH2A.X level, respectively. These findings suggest that isoflurane might induce DNA damage, as represented by increased γH2A.X level, via induction of oxidative stress and inhibition of the repair of DNA damage through the p53 signaling pathway.
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Affiliation(s)
- Cheng Ni
- Department of Anesthesiology, Peking University Third Hospital, 49 North Garden Rd., Haidian District, Beijing, 100191, China
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, 149 13th St., Room 4310, Charlestown, MA, 02129, USA
| | - Cheng Li
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, 149 13th St., Room 4310, Charlestown, MA, 02129, USA
- Department of Anesthesiology, Shanghai Tenth People's Hospital, Tongji University, Shanghai, 200072, China
| | - Yuanlin Dong
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, 149 13th St., Room 4310, Charlestown, MA, 02129, USA
| | - Xiangyang Guo
- Department of Anesthesiology, Peking University Third Hospital, 49 North Garden Rd., Haidian District, Beijing, 100191, China
| | - Yiying Zhang
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, 149 13th St., Room 4310, Charlestown, MA, 02129, USA
| | - Zhongcong Xie
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, 149 13th St., Room 4310, Charlestown, MA, 02129, USA.
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Kim GH, Lee JJ, Lee SH, Chung YH, Cho HS, Kim JA, Kim MK. Exposure of isoflurane-treated cells to hyperoxia decreases cell viability and activates the mitochondrial apoptotic pathway. Brain Res 2016; 1636:13-20. [PMID: 26854136 DOI: 10.1016/j.brainres.2016.01.052] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 01/21/2016] [Accepted: 01/30/2016] [Indexed: 11/30/2022]
Abstract
Isoflurane has either neuroprotective or neurotoxic effects. High-dose oxygen is frequently used throughout the perioperative period. We hypothesized that hyperoxia will affect cell viability of rat pheochromocytoma (PC12) cells that were exposed to isoflurane and reactive oxygen species (ROS) may be involved. PC12 cells were exposed to 1.2% or 2.4% isoflurane for 6 or 24h respectively, and cell viability was evaluated. To investigate the effects of hyperoxia, PC12 cells were treated with 21%, 50%, or 95% oxygen and 2.4% isoflurane for 6h, and cell viability, TUNEL staining, ROS production, and expression of B-cell lymphoma 2 (BCL-2), BCL2-associated X protein (BAX), caspase-3 and beta-site APP cleaving enzyme (BACE) were measured. ROS involvement was evaluated using the ROS scavenger 2-mercaptopropiopylglycine (MPG). The viability of cells exposed to 2.4% isoflurane was lower than that of cells exposed to 1.2% isoflurane. Prolonged exposure (6h vs. 24h) to 2.4% isoflurane resulted in a profound reduction in cell viability. Treatment with 95% (but not 50%) oxygen enhanced the decrease in cell viability induced by 2.4% isoflurane alone. Levels of ROS, Bax, caspase-3 and BACE were increased, whereas expression of Bcl-2 was decreased, in cells treated with 95% oxygen plus 2.4% isoflurane compared with the control and 2.4% isoflurane plus air groups. MPG attenuated the effects of oxygen and isoflurane. In conclusion, isoflurane affects cell viability in a dose- and time-dependent manner. This effect is augmented by hyperoxia and may involve ROS, the mitochondrial apoptotic signaling pathway, and β-amyloid protein.
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Affiliation(s)
- Gunn Hee Kim
- Department of Anesthesiology and Pain Medicine, National Medical Center, South Korea
| | - Jeong Jin Lee
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-gu, Seoul 135-710, South Korea.
| | - Sang Hyun Lee
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-gu, Seoul 135-710, South Korea
| | - Yang Hoon Chung
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-gu, Seoul 135-710, South Korea
| | - Hyun Sung Cho
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-gu, Seoul 135-710, South Korea
| | - Jie Ae Kim
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-gu, Seoul 135-710, South Korea
| | - Min Kyung Kim
- Samsung Biomedical Research Institute, Seoul, South Korea
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Lin EP, Lee JR, Loepke AW. Anesthetics and the Developing Brain: The Yin and Yang. CURRENT ANESTHESIOLOGY REPORTS 2015. [DOI: 10.1007/s40140-015-0107-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Bajwa SJS, Anand S, Gupta H. Perils of paediatric anaesthesia and novel molecular approaches: An evidence-based review. Indian J Anaesth 2015; 59:272-81. [PMID: 26019351 PMCID: PMC4445148 DOI: 10.4103/0019-5049.156865] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Evolution of anaesthesia has been largely helped by progress of evidence-based medicine. In spite of many advancements in anaesthesia techniques and availability of newer and safer drugs, much more needs to be explored scientifically for the development of anaesthesia. Over the last few years, the notion that the actions of the anaesthesiologist have only immediate or short-term consequences has largely been challenged. Evidences accumulated in the recent years have shown that anaesthesia exposure may have long-term consequences particularly in the extremes of ages. However, most of the studies conducted so far are in vitro or animal studies, the results of which have been extrapolated to humans. There have been confounding evidences linking anaesthesia exposure in the developing brain with poor neurocognitive outcome. The results of animal studies and human retrospective studies have raised concern over the potential detrimental effects of general anaesthetics on the developing brain. The purpose of this review is to highlight the long-term perils of anaesthesia in the very young and the potential of improving anaesthesia delivery with the novel molecular approaches.
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Affiliation(s)
- Sukhminder Jit Singh Bajwa
- Department of Anaesthesiology and Intensive Care, Gian Sagar Medical College and Hospital, Banur, Punjab, India
| | - Smriti Anand
- Department of Anaesthesiology and Intensive Care, Maharishi Markendeshwar Medical College and Hospital, Kumarhatti, Solan, Himachal Pradesh, India
| | - Hemant Gupta
- Department of Paediatrics, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India
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Lee JH, Zhang J, Wei L, Yu SP. Neurodevelopmental implications of the general anesthesia in neonate and infants. Exp Neurol 2015; 272:50-60. [PMID: 25862287 DOI: 10.1016/j.expneurol.2015.03.028] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 03/26/2015] [Accepted: 03/31/2015] [Indexed: 12/17/2022]
Abstract
Each year, about six million children, including 1.5 million infants, in the United States undergo surgery with general anesthesia, often requiring repeated exposures. However, a crucial question remains of whether neonatal anesthetics are safe for the developing central nervous system (CNS). General anesthesia encompasses the administration of agents that induce analgesic, sedative, and muscle relaxant effects. Although the mechanisms of action of general anesthetics are still not completely understood, recent data have suggested that anesthetics primarily modulate two major neurotransmitter receptor groups, either by inhibiting N-methyl-D-aspartate (NMDA) receptors, or conversely by activating γ-aminobutyric acid (GABA) receptors. Both of these mechanisms result in the same effect of inhibiting excitatory activity of neurons. In developing brains, which are more sensitive to disruptions in activity-dependent plasticity, this transient inhibition may have longterm neurodevelopmental consequences. Accumulating reports from preclinical studies show that anesthetics in neonates cause cellular toxicity including apoptosis and neurodegeneration in the developing brain. Importantly, animal and clinical studies indicate that exposure to general anesthetics may affect CNS development, resulting in long-lasting cognitive and behavioral deficiencies, such as learning and memory deficits, as well as abnormalities in social memory and social activity. While the casual relationship between cellular toxicity and neurological impairments is still not clear, recent reports in animal experiments showed that anesthetics in neonates can affect neurogenesis, which could be a possible mechanism underlying the chronic effect of anesthetics. Understanding the cellular and molecular mechanisms of anesthetic effects will help to define the scope of the problem in humans and may lead to preventive and therapeutic strategies. Therefore, in this review, we summarize the current evidence on neonatal anesthetic effects in the developmental CNS and discuss how factors influencing these processes can be translated into new therapeutic strategies.
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Affiliation(s)
- Jin Hwan Lee
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - James Zhang
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Ling Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Shan Ping Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA; Center for Visual and Neurocognitive Rehabilitation, VA Medical Center, Atlanta, GA 30033, USA.
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Sun Y, Zhang Y, Cheng B, Dong Y, Pan C, Li T, Xie Z. Glucose may attenuate isoflurane-induced caspase-3 activation in H4 human neuroglioma cells. Anesth Analg 2015; 119:1373-80. [PMID: 25068691 DOI: 10.1213/ane.0000000000000383] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND The commonly used inhaled anesthetic isoflurane has been shown to induce caspase-3 activation. However, the underlying mechanism(s) and targeted intervention(s) remain largely to be determined. Isoflurane may induce caspase-3 activation via causing accumulation of reactive oxygen species (ROS), mitochondrial dysfunction, and reduction in adenosine triphosphate (ATP) levels. Therefore, we performed a hypothesis-generation study to determine whether glucose could attenuate isoflurane-induced caspase-3 activation, ROS accumulation, mitochondrial dysfunction, and ATP reduction in cultured cells. METHODS H4 human neuroglioma cells (H4 cells) were treated with 2% isoflurane or the control condition plus saline or 50 mM glucose for 6 or 3 hours. Caspase-3 activation, cell viability, levels of ROS and ATP, and mitochondrial membrane potential were determined at the end of the experiments by Western blot analysis and fluorescence assay. RESULTS We found that the glucose treatment might attenuate isoflurane-induced caspase-3 activation and reduction of cell viability in H4 cells. Moreover, the glucose treatment mitigated the isoflurane-induced increase in ROS levels and reduction in ATP levels in H4 cells. Unexpectedly, we observed that the glucose treatment might not inhibit the isoflurane-induced decrease in mitochondrial membrane potential in H4 cells. CONCLUSIONS Pending further studies, these results suggested that glucose might attenuate isoflurane-induced caspase-3 activation through a mitochondria-independent reduction in ROS levels and enhancement in ATP levels. These findings have established a system and suggest that it is worth performing more research to further investigate whether glucose can attenuate anesthesia neurotoxicity.
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Affiliation(s)
- Yongxing Sun
- From the *Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts; and †Department of Anesthesia, Beijing Tongren Hospital, Capital Medical University, Beijing, P.R. China
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Hirsch S, Dickenson A, Corradini L. Anesthesia influences neuronal activity and drug effectiveness in neuropathic rats. Pain 2014; 155:2583-2590. [DOI: 10.1016/j.pain.2014.09.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 09/16/2014] [Accepted: 09/16/2014] [Indexed: 01/16/2023]
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Peng J, Drobish JK, Liang G, Wu Z, Liu C, Joseph DJ, Abdou H, Eckenhoff MF, Wei H. Anesthetic preconditioning inhibits isoflurane-mediated apoptosis in the developing rat brain. Anesth Analg 2014; 119:939-946. [PMID: 25099925 DOI: 10.1213/ane.0000000000000380] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND We hypothesized that preconditioning (PC) with a short exposure to isoflurane (ISO) would reduce neurodegeneration induced by prolonged exposure to ISO in neonatal rats, as previously shown in neuronal cell culture. METHODS We randomly divided 7-day-old Sprague-Dawley rats into 3 groups: control, 1.5% ISO, and PC + 1.5% ISO. The control group was exposed to carrier gas (30% oxygen balanced in nitrogen) for 30 minutes and then to carrier gas again for 6 hours the following day. The 1.5% ISO group was exposed to carrier gas for 30 minutes and then to 1.5% ISO for 6 hours the following day. The PC + 1.5% ISO group was preconditioned with a 30-minute 1.5% ISO exposure and then exposed to 1.5% ISO for 6 hours the following day. Blood and brain samples were collected 2 hours after the exposures for determination of neurodegenerative biomarkers, including caspase-3, S100β, caspase-12, and an autophagy biomarker Beclin-1. RESULTS Prolonged exposure to ISO significantly increased cleaved caspase-3 expression in the cerebral cortex of 7-day-old rats compared with the group preconditioned with ISO and the controls using Western blot assays. However, significant differences were not detected for other markers of neuronal injury. CONCLUSIONS The ISO-mediated increase in cleaved caspase-3 in the postnatal day 7 rat brain is ameliorated by PC with a brief anesthetic exposure, and differences were not detected in other markers of neuronal injury.
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Affiliation(s)
- Jun Peng
- From the Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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Vitamin C Attenuates Isoflurane-Induced Caspase-3 Activation and Cognitive Impairment. Mol Neurobiol 2014; 52:1580-1589. [PMID: 25367886 DOI: 10.1007/s12035-014-8959-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Accepted: 10/21/2014] [Indexed: 10/24/2022]
Abstract
Anesthetic isoflurane has been reported to induce caspase-3 activation. The underlying mechanism(s) and targeted intervention(s), however, remain largely to be determined. Vitamin C (VitC) inhibits oxidative stress and apoptosis. We therefore employed VitC to further determine the up-stream mechanisms and the down-stream consequences of the isoflurane-induced caspase-3 activation. H4 human neuroglioma cells overexpressed human amyloid precursor protein (H4-APP cells) and rat neuroblastoma cells were treated either with (1) 2% isoflurane or (2) with the control condition, plus saline or 400 μM VitC for 3 or 6 h. Western blot analysis and fluorescence assay were utilized at the end of the experiments to determine caspase-3 activation, levels of reactive oxygen species and ATP, and mitochondrial function. The interaction of isoflurane (1.4% for 2 h) and VitC (100 mg/kg) on cognitive function in mice was also assessed in the fear conditioning system. Here, we show for the first time that the VitC treatment attenuated the isoflurane-induced caspase-3 activation. Moreover, VitC mitigated the isoflurane-induced increases in the levels of reactive oxygen species, opening of mitochondrial permeability transition pore, reduction in mitochondrial membrane potential, and the reduction in ATP levels in the cells. Finally, VitC ameliorated the isoflurane-induced cognitive impairment in the mice. Pending confirmation from future studies, these results suggested that VitC attenuated the isoflurane-induced caspase-3 activation and cognitive impairment by inhibiting the isoflurane-induced oxidative stress, mitochondrial dysfunction, and reduction in ATP levels. These findings would promote further research into the underlying mechanisms and targeted interventions of anesthesia neurotoxicity.
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Liu H, Dai T, Guo W. Isoflurane-induced neuronal apoptosis in developing hippocampal neurons. Neural Regen Res 2014; 8:825-32. [PMID: 25206730 PMCID: PMC4146089 DOI: 10.3969/j.issn.1673-5374.2013.09.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 01/19/2013] [Indexed: 11/23/2022] Open
Abstract
We hypothesized that the P2X7 receptor may be the target of isoflurane, so we investigated the roles of the P2X7 receptor and inositol triphosphate receptor in calcium overload and neuronal apoptosis induced by isoflurane in cultured embryonic rat hippocampal neurons. Results showed that isoflurane induced widespread neuronal apoptosis and significantly increased cytoplasmic Ca2+. Blockade of P2X7 receptors or removal of extracellular Ca2+ combined with blockade of inositol triphosphate receptors completely inhibited apoptosis or increase in cytoplasmic Ca2+. Removal of extracellular Ca2+ or blockade of inositol triphosphate receptor alone could partly inhibit these effects of isoflurane. Isoflurane could directly activate P2X7-gated channels and induce inward currents, but did not affect the expression of P2X7 receptor protein in neurons. These findings indicate that the mechanism by which isoflurane induced neuronal apoptosis in rat developing brain was mediated by intracellular calcium overload, which was caused by P2X7 receptor mediated calcium influx and inositol triphosphate receptor mediated calcium release.
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Affiliation(s)
- Hongliang Liu
- Department of Anesthesiology, Chongqing Cancer Institute/Cancer Hospital, Chongqing 400030, China
| | - Tijun Dai
- Department of Pharmacology, Xuzhou Medical College, Xuzhou 221002, Jiangsu Province, China
| | - Weitao Guo
- Department of Orthopedics Affiliated Hospital, Guangdong Medical College, Zhanjiang 524000, Guangdong Province, China
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Liao Z, Cao D, Han X, Liu C, Peng J, Zuo Z, Wang F, Li Y. Both JNK and P38 MAPK pathways participate in the protection by dexmedetomidine against isoflurane-induced neuroapoptosis in the hippocampus of neonatal rats. Brain Res Bull 2014; 107:69-78. [PMID: 25026397 DOI: 10.1016/j.brainresbull.2014.07.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 07/01/2014] [Accepted: 07/03/2014] [Indexed: 12/12/2022]
Abstract
Dexmedetomidine, a highly selective α2-adrenergic agonist, has been reported to attenuate isoflurane-induced cognitive impairment and neuroapoptosis. However, the underlying molecular mechanisms remain poorly understood. The aim of this study was to investigate whether mitogen-activated protein kinase (MAPK) pathway was involved in dexmedetomidine-induced neuroprotection against isoflurane effects. Seven-day-old (P7) neonatal Sprague-Dawley rats were pretreated with various concentrations of dexmedetomidine, and then exposed to 0.75% isoflurane or air for 6h. Terminal deoxyribonucleotide transferase-mediated dUTP nick end labeling (TUNEL) was used to detect neuronal apoptosis in their hippocampus. Activated caspase-3, extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun NH2-terminal kinases (JNK), p38, phospho-ERK1/2, phospho-JNK and phospho-p38 proteins were detected by Western blotting in the hippocampus at the end of exposure. Also, P7 rats were pretreated with 75 μg/kg dexmedetomidine alone, or given the ERK inhibitor U0126 before dexmedetomidine pretreatment, or pretreated with the p38 MAPK inhibitor SB203580 or JNK inhibitor SP600125 alone, and then exposed to 0.75% isoflurane for 6h. Isoflurane induced significant neuroapoptosis, increased the protein expression of phospho-JNK, phospho-c-Jun, phospho-p38 and phospho-nuclear factor-κB (NF-κB), decreased the level of phospho-ERK1/2 protein and reduced the ratio of Bcl-2/Bax in the hippocampus. Dexmedetomidine pretreatment inhibited isoflurane-induced neuroapoptosis and restored proteins expression of MAPK pathways and the Bcl-2/Bax ratio after isoflurane exposure. Moreover, SB203580 and SP600125 also partly attenuated the isoflurane-induced protein changes. However, U0126 did not reverse dexmedetomidine-induced neuroprotection. Our results indicate that the JNK and p38 pathways, not the ERK pathway are involved in dexmedetomidine-induced neuroprotection against isoflurane effects.
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Affiliation(s)
- Zhaoxia Liao
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China.
| | - Dexiong Cao
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China.
| | - Xue Han
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China.
| | - Chuiliang Liu
- Department of Anesthesiology, ChanCheng Center Hospital, Foshan 528030, China.
| | - Jun Peng
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China.
| | - Zhiyi Zuo
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China; Department of Anesthesiology, University of Virginia Health System, PO Box 800710, Charlottesville, VA 22908-0710, USA.
| | - Fei Wang
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China.
| | - Yujuan Li
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China.
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Giles EK, Lawrence AJ, Duncan JR. Exploring the Modulation of Hypoxia-Inducible Factor (HIF)-1α by Volatile Anesthetics as a Possible Mechanism Underlying Volatile Anesthetic-Induced CNS Injury. Neurochem Res 2014; 39:1640-7. [DOI: 10.1007/s11064-014-1379-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 06/26/2014] [Accepted: 06/30/2014] [Indexed: 12/11/2022]
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Effects of repetitive exposure to anesthetics and analgesics in the Tg2576 mouse Alzheimer's model. Neurotox Res 2014; 26:414-21. [PMID: 24927827 DOI: 10.1007/s12640-014-9478-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 04/28/2014] [Accepted: 05/23/2014] [Indexed: 10/25/2022]
Abstract
The use of anesthetics and sedatives has been suggested to be a contributor to Alzheimer's disease neuropathogenesis. We wanted to address the in vivo relevance of those substances in the Tg2576 Alzheimer's mouse model. Tg7526 mice were anesthesia-sedated for 90 min once a week for 4 weeks. Y maze, Congo Red, and amyloid beta (Aβ) immunochemistry were performed. We did not find any significant change in the navigation behavior of the exposed mice compared to the controls. Significantly less deposition of Aβ in the CA1 area of the hippocampus and frontal cortex of mice exposed to isoflurane, propofol, diazepam, ketamine, and pentobarbital was observed. In the dentate gyrus, Aβ deposition was significantly greater in the group treated with pentobarbital. Congo Red staining evidenced significantly fewer fibrils in the cortex of mice exposed to diazepam, ketamine, or pentobarbital. The adopted repetitive exposure did not cause a significant detriment in Tg7526 mouse.
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Time-Dependent Effects of Anesthetic Isoflurane on Reactive Oxygen Species Levels in HEK-293 Cells. Brain Sci 2014; 4:311-20. [PMID: 24961763 PMCID: PMC4101479 DOI: 10.3390/brainsci4020311] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 04/04/2014] [Accepted: 04/04/2014] [Indexed: 11/17/2022] Open
Abstract
The inhalation anesthetic isoflurane has been reported to induce caspase activation and apoptosis, which may lead to learning and memory impairment. However, the underlying mechanisms of these effects are largely unknown. Isoflurane has been shown to induce elevation of cytosol calcium levels, accumulation of reactive oxygen species (ROS), opening of the mitochondrial permeability transition pore, reduction in mitochondria membrane potential, and release of cytochrome c. The time course of these effects, however, remains to be determined. Therefore, we performed a pilot study to determine the effects of treatment with isoflurane for various times on ROS levels in HEK-293 cells. The cells were treated with 2% isoflurane plus 21% O2 and 5% CO2 for 15, 30, 60, or 90 min. We then used fluorescence imaging and microplate fluorometer to detect ROS levels. We show that 2% isoflurane for 60 or 90 min, but not 15 or 30 min, induced ROS accumulation in the cells. These data illustrated that isoflurane could cause time-dependent effects on ROS levels. These findings have established a system to further determine the time course effects of isoflurane on cellular and mitochondria function. Ultimately, the studies would elucidate, at least partially, the underlying mechanisms of isoflurane-induced cellular toxicity.
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Wei H, Inan S. Dual effects of neuroprotection and neurotoxicity by general anesthetics: role of intracellular calcium homeostasis. Prog Neuropsychopharmacol Biol Psychiatry 2013; 47:156-61. [PMID: 23721657 PMCID: PMC3791176 DOI: 10.1016/j.pnpbp.2013.05.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 04/18/2013] [Accepted: 05/15/2013] [Indexed: 11/18/2022]
Abstract
Although general anesthetics have long been considered neuroprotective, there are growing concerns about neurotoxicity. Preclinical studies clearly demonstrated that commonly used general anesthetics are both neuroprotective and neurotoxic, with unclear mechanisms. Recent studies suggest that differential activation of inositol 1,4,5-trisphosphate receptors, a calcium release channel located on the membrane of endoplasmic reticulum (ER), play important role on determining the fate of neuroprotection or neurotoxicity by general anesthetics. General anesthetics at low concentrations for short duration are sublethal stress factors which induce endogenous neuroprotective mechanisms and provide neuroprotection via adequate activation of InsP3R and moderate calcium release from ER. On the other hand, general anesthetics at high concentrations for prolonged duration are lethal stress factors which induce neuronal damage by over activation of InsP3R and excessive and abnormal Ca(2+) release from ER. This review emphasizes the dual effects of both neuroprotection and neurotoxicity via differential regulation of intracellular Ca(2+) homeostasis by commonly used general anesthetics and recommends strategy to maximize neuroprotective but minimize neurotoxic effects of general anesthetics.
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Affiliation(s)
- Huafeng Wei
- Department of Anesthesiology and Critical Care, University of Pennsylvania, 305 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA 19104, USA.
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General anesthetics and β-amyloid protein. Prog Neuropsychopharmacol Biol Psychiatry 2013; 47:140-6. [PMID: 22918033 PMCID: PMC3510311 DOI: 10.1016/j.pnpbp.2012.08.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 08/02/2012] [Accepted: 08/02/2012] [Indexed: 11/23/2022]
Abstract
With roughly 234 million people undergoing surgery with anesthesia each year worldwide, it is important to determine whether commonly used anesthetics can induce any neurotoxicity. Alzheimer's disease (AD) is the most common form of age-related dementia, and a rapidly growing health problem. Several studies suggest that anesthesia could be associated with the development of AD. Moreover, studies in cultured cells and animals show that commonly used inhalation anesthetics may induce changes consistent with AD neuropathogenesis, e.g., β-amyloid protein accumulation. Therefore, in this mini review, we focus on the recent research investigating the effects of commonly used anesthetics including isoflurane, sevoflurane, desflurane, nitrous oxide, and propofol, on Aβ accumulation in vitro and in vivo. We further discuss the future direction of the research determining the effects of anesthetics on β-amyloid protein accumulation.
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Patkai J, Zana-Taieb E, Didier C, Jarreau PH, Lopez E. Aspects fondamentaux de la toxicite éventuelle des drogues anesthésiques. Arch Pediatr 2013; 20:1059-66. [DOI: 10.1016/j.arcped.2013.06.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 06/21/2013] [Accepted: 06/24/2013] [Indexed: 01/08/2023]
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Dual effects of isoflurane on proliferation, differentiation, and survival in human neuroprogenitor cells. Anesthesiology 2013; 118:537-49. [PMID: 23314167 DOI: 10.1097/aln.0b013e3182833fae] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Previous studies have demonstrated that isoflurane can provide both neuroprotection and neurotoxicity in various tissue culture models and in rodent developing brains. The cellular and molecular mechanisms mediating these dual effects are not clear, but the exposure level and duration of isoflurane appear to be determinant factors. METHODS Using the ReNcell CX (Millipore, Billerica, MA) human neural progenitor cell line, the authors investigated the impact of prolonged exposure to varying isoflurane concentrations on cell survival and neurogenesis. In addition, the authors assessed the impact of short isoflurane preconditioning on elevation of cytosolic Ca concentration and cytotoxic effects mediated by prolonged isoflurane exposures and the contribution of inositol-1,4,5-trisphosphate or ryanodine receptor activation to these processes. RESULTS Short exposures to low isoflurane concentrations promote proliferation and differentiation of ReNcell CX cells, with no cell damage. However, prolonged exposures to high isoflurane concentrations induced significant ReNcell CX cell damage and inhibited cell proliferation. These prolonged exposures suppressed neuronal cell fate and promoted glial cell fate. Preconditioning of ReNcell CX cultures with short exposures to low concentrations of isoflurane ameliorated the effects of prolonged exposures to isoflurane. Pretreatment of ReNcell cultures with inositol-1,4,5-trisphosphate or ryanodine receptor antagonists mostly prevented isoflurane-mediated effects on survival, proliferation, and differentiation. Finally, isoflurane-preconditioned cultures showed significantly less isoflurane-evoked changes in calcium concentration. CONCLUSION The commonly used general anesthetic isoflurane exerts dual effects on neuronal stem cell survival, proliferation, and differentiation, which may be attributed to differential regulation of calcium release through activation of endoplasmic reticulum localized inositol-1,4,5-trisphosphate and/or ryanodine receptors.
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Istaphanous GK, Ward CG, Nan X, Hughes EA, McCann JC, McAuliffe JJ, Danzer SC, Loepke AW. Characterization and quantification of isoflurane-induced developmental apoptotic cell death in mouse cerebral cortex. Anesth Analg 2013; 116:845-54. [PMID: 23460572 DOI: 10.1213/ane.0b013e318281e988] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Accumulating evidence indicates that isoflurane and other, similarly acting anesthetics exert neurotoxic effects in neonatal animals. However, neither the identity of dying cortical cells nor the extent of cortical cell loss has been sufficiently characterized. We conducted the present study to immunohistochemically identify the dying cells and to quantify the fraction of cells undergoing apoptotic death in neonatal mouse cortex, a substantially affected brain region. METHODS Seven-day-old littermates (n = 36) were randomly assigned to a 6-hour exposure to either 1.5% isoflurane or fasting in room air. Animals were euthanized immediately after exposure and brain sections were double-stained for activated caspase 3 and one of the following cellular markers: Neuronal Nuclei (NeuN) for neurons, glutamic acid decarboxylase (GAD)65 and GAD67 for GABAergic cells, as well as GFAP (glial fibrillary acidic protein) and S100β for astrocytes. RESULTS In 7-day-old mice, isoflurane exposure led to widespread increases in apoptotic cell death relative to controls, as measured by activated caspase 3 immunolabeling. Confocal analyses of caspase 3-labeled cells in cortical layers II and III revealed that the overwhelming majority of cells were postmitotic neurons, but some were astrocytes. We then quantified isoflurane-induced neuronal apoptosis in visual cortex, an area of substantial injury. In unanesthetized control animals, 0.08% ± 0.001% of NeuN-positive layer II/III cortical neurons were immunoreactive for caspase 3. By contrast, the rate of apoptotic NeuN-positive neurons increased at least 11-fold (lower end of the 95% confidence interval [CI]) to 2.0% ± 0.004% of neurons immediately after isoflurane exposure (P = 0.0017 isoflurane versus control). In isoflurane-treated animals, 2.9% ± 0.02% of all caspase 3-positive neurons in superficial cortex also coexpressed GAD67, indicating that inhibitory neurons may also be affected. Analysis of GABAergic neurons, however, proved unexpectedly complex. In addition to inducing apoptosis among some GAD67-immunoreactive neurons, anesthesia also coincided with a dramatic decrease in both GAD67 (0.98 vs 1.84 ng/mg protein, P < 0.00001, anesthesia versus control) and GAD65 (2.25 ± 0.74 vs 23.03 ± 8.47 ng/mg protein, P = 0.0008, anesthesia versus control) protein levels. CONCLUSIONS Prolonged exposure to isoflurane increased neuronal apoptotic cell death in 7-day-old mice, eliminating approximately 2% of cortical neurons, of which some were identified as GABAergic interneurons. Moreover, isoflurane exposure interfered with the inhibitory nervous system by downregulating the central enzymes GAD65 and GAD67. Conversely, at this age, only a minority of degenerating cells were identified as astrocytes. The clinical relevance of these findings in animals remains to be determined.
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Affiliation(s)
- George K Istaphanous
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
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Su D, Zhao Y, Xu H, Wang B, Chen X, Chen J, Wang X. Isoflurane exposure during mid-adulthood attenuates age-related spatial memory impairment in APP/PS1 transgenic mice. PLoS One 2012. [PMID: 23185565 PMCID: PMC3501473 DOI: 10.1371/journal.pone.0050172] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Many in vitro findings suggest that isoflurane exposure might accelerate the process of Alzheimer Disease (AD); however, no behavioral evidence exists to support this theory. In the present study, we hypothesized that exposure of APP/PS1 transgenic mice to isoflurane during mid-adulthood, which is the pre-symptomatic phase of amyloid beta (Abeta) deposition, would alter the progression of AD. Seven-month-old Tg(APPswe,PSEN1dE9)85Dbo/J transgenic mice and their wild-type littermates were exposed to 1.1% isoflurane for 2 hours per day for 5 days. Learning and memory ability was tested 48 hours and 5 months following isoflurane exposure using the Morris Water Maze and Y maze, respectively. Abeta deposition and oligomers in the hippocampus were measured by immunohistochemistry or Elisa 5 months following isoflurane exposure. We found that the performance of both the transgenic and wild-type mice in the Morris Water Maze significantly improved 48 hours following isoflurane exposure. The transgenic mice made significantly fewer discrimination errors in the Y maze following isoflurane exposure, and no differences were found between wild-type littermates 5 months following isoflurane exposure. For the transgenic mice, the Abeta plaque and oligomers in the hippocampus was significantly decreased in the 5 months following isoflurane exposure. In summary, repeated isoflurane exposure during the pre-symptomatic phase not only improved spatial memory in both the APP/PS1 transgenic and wild-type mice shortly after the exposure but also prevented age-related decline in learning and memory and attenuated the Abeta plaque and oligomers in the hippocampus of transgenic mice.
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Affiliation(s)
- Diansan Su
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Yanxing Zhao
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Huan Xu
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Beilei Wang
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Xuemei Chen
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Jie Chen
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Xiangrui Wang
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
- * E-mail:
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Jevtovic-Todorovic V, Boscolo A, Sanchez V, Lunardi N. Anesthesia-induced developmental neurodegeneration: the role of neuronal organelles. Front Neurol 2012; 3:141. [PMID: 23087668 PMCID: PMC3468830 DOI: 10.3389/fneur.2012.00141] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Accepted: 09/24/2012] [Indexed: 01/12/2023] Open
Abstract
Exposure to general anesthetics (GAs) and antiepileptics during critical stages of brain development causes significant neurotoxicity to immature neurons. Many animal, and emerging human studies have shown long-term functional sequelae manifested as behavioral deficits and cognitive impairments. Since GAs and antiepileptic drugs are a necessity, current research is focused on deciphering the mechanisms responsible for anesthesia-induced developmental neurotoxicity so that protective strategies can be devised. These agents promote massive and wide-spread neuroapoptosis that is caused by the impairment of integrity and function of neuronal organelles. Mitochondria and endoplasmic reticulum are particularly vulnerable. By promoting significant release of intracellular calcium from the endoplasmic reticulum, anesthetics cause an increase in mitochondrial calcium load resulting in the loss of their integrity, release of pro-apoptotic factors, functional impairment of ATP synthesis, and enhanced accumulation of reactive oxygen species. The possibility that GAs may have direct damaging effects on mitochondria, resulting in the impairment of their morphogenesis, also has been proposed. This review will present evidence that neuronal organelles are critical and early targets of anesthesia-induced developmental neurotoxicity.
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Affiliation(s)
- Vesna Jevtovic-Todorovic
- Department of Anesthesiology, University of Virginia Health System Charlottesville, VA, USA ; Neuroscience Graduate Program, University of Virginia Charlottesville, VA, USA
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Zhang Y, Dong Y, Xu Z, Xie Z. Propofol and magnesium attenuate isoflurane-induced caspase-3 activation via inhibiting mitochondrial permeability transition pore. Med Gas Res 2012; 2:20. [PMID: 22901676 PMCID: PMC3489514 DOI: 10.1186/2045-9912-2-20] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Accepted: 08/03/2012] [Indexed: 11/25/2022] Open
Abstract
Background The inhalation anesthetic isoflurane has been shown to open the mitochondrial permeability transition pore (mPTP) and induce caspase activation and apoptosis, which may lead to learning and memory impairment. Cyclosporine A, a blocker of mPTP opening might attenuate the isoflurane-induced mPTP opening, lessening its ripple effects. Magnesium and anesthetic propofol are also mPTP blockers. We therefore set out to determine whether propofol and magnesium can attenuate the isoflurane-induced caspase activation and mPTP opening. Methods We investigated the effects of magnesium sulfate (Mg2+), propofol, and isoflurane on the opening of mPTP and caspase activation in H4 human neuroglioma cells stably transfected to express full-length human amyloid precursor protein (APP) (H4 APP cells) and in six day-old wild-type mice, employing Western blot analysis and flowcytometry. Results Here we show that Mg2+ and propofol attenuated the isoflurane-induced caspase-3 activation in H4-APP cells and mouse brain tissue. Moreover, Mg2+ and propofol, the blockers of mPTP opening, mitigated the isoflurane-induced mPTP opening in the H4-APP cells. Conclusion These data illustrate that Mg2+ and propofol may ameliorate the isoflurane-induced neurotoxicity by inhibiting its mitochondrial dysfunction. Pending further studies, these findings may suggest the use of Mg2+ and propofol in preventing and treating anesthesia neurotoxicity.
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Affiliation(s)
- Yiying Zhang
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, 149 13th St, Room 4310, Charlestown, MA, 02129-2060, USA.
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GAPDH in anesthesia. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 985:269-91. [PMID: 22851453 DOI: 10.1007/978-94-007-4716-6_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Thus far, two independent laboratories have shown that inhaled anesthetics directly affect GAPDH structure and function. Additionally, it has been demonstrated that GAPDH normally regulates the function of GABA (type A) receptor. In light of these literature observations and some less direct findings, there is a discussion on the putative role of GAPDH in anesthesia. The binding site of inhaled anesthetics is described from literature reports on model proteins, such as human serum albumin and apoferritin. In addition to the expected hydrophobic residues that occupy the binding cavity, there are hydrophilic residues at or in very close proximity to the site of anesthetic binding. A putative binding site in the bacterial analog of the human GABA (type A) receptor is also described. Additionally, GAPDH may also play a role in anesthetic preconditioning, a phenomenon that confers protection of cells and tissues to future challenges by noxious stimuli. The central thesis regarding this paradigm is that inhaled anesthetics evoke an intra-molecular protein dehydration that is recognized by the cell, eliciting a very specific burst of chaperone gene expression. The chaperones that are implicated are associated with conferring protection against dehydration-induced protein aggregation.
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Lei X, Guo Q, Zhang J. Mechanistic insights into neurotoxicity induced by anesthetics in the developing brain. Int J Mol Sci 2012; 13:6772-6799. [PMID: 22837663 PMCID: PMC3397495 DOI: 10.3390/ijms13066772] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 05/12/2012] [Accepted: 05/25/2012] [Indexed: 11/16/2022] Open
Abstract
Compelling evidence has shown that exposure to anesthetics used in the clinic can cause neurodegeneration in the mammalian developing brain, but the basis of this is not clear. Neurotoxicity induced by exposure to anesthestics in early life involves neuroapoptosis and impairment of neurodevelopmental processes such as neurogenesis, synaptogenesis and immature glial development. These effects may subsequently contribute to behavior abnormalities in later life. In this paper, we reviewed the possible mechanisms of anesthetic-induced neurotoxicity based on new in vitro and in vivo findings. Also, we discussed ways to protect against anesthetic-induced neurotoxicity and their implications for exploring cellular and molecular mechanisms of neuroprotection. These findings help in improving our understanding of developmental neurotoxicology and in avoiding adverse neurological outcomes in anesthesia practice.
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Affiliation(s)
- Xi Lei
- Department of Anesthesiology, Huashan Hospital, Fudan University, Shanghai 200040, China; E-Mail:
| | - Qihao Guo
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai 200040, China; E-Mail:
| | - Jun Zhang
- Department of Anesthesiology, Huashan Hospital, Fudan University, Shanghai 200040, China; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +86-21-52887693; Fax: +86-21-52887690
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Dabrowski W, Rzecki Z, Czajkowski M, Pilat J, Wacinski P, Kotlinska E, Sztanke M, Sztanke K, Stazka K, Pasternak K. Volatile Anesthetics Reduce Biochemical Markers of Brain Injury and Brain Magnesium Disorders in Patients Undergoing Coronary Artery Bypass Graft Surgery. J Cardiothorac Vasc Anesth 2012; 26:395-402. [DOI: 10.1053/j.jvca.2011.10.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Indexed: 11/11/2022]
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Xu Z, Dong Y, Wu X, Zhang J, McAuliffe S, Pan C, Zhang Y, Ichinose F, Yue Y, Xie Z. The potential dual effects of anesthetic isoflurane on Aβ-induced apoptosis. Curr Alzheimer Res 2012; 8:741-52. [PMID: 21244349 DOI: 10.2174/156720511797633223] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Revised: 02/06/2011] [Accepted: 02/08/2011] [Indexed: 01/06/2023]
Abstract
β-amyloid protein (Aβ)-induced neurotoxicity is the main component of Alzheimer's disease (AD) neuropathogenesis. Inhalation anesthetics have long been considered to protect against neurotoxicity. However, recent research studies have suggested that the inhalation anesthetic isoflurane may promote neurotoxicity by inducing apoptosis and increasing Aβ levels. We therefore set out to determine whether isoflurane can induce dose- and time-dependent dual effects on Aβ-induced apoptosis: protection versus promotion. H4 human neuroglioma cells, primary neurons from naive mice, and naive mice were treated with Aβ and/or isoflurane, and levels of caspase-3 cleavage (activation), apoptosis, Bcl-2, Bax, and cytosolic calcium were determined. Here we show for the first time that the treatment with 2% isoflurane for six hours or 30 minutes potentiated, whereas the treatment with 0.5% isoflurane for six hours or 30 minutes attenuated, the Aβ-induced caspase-3 activation and apoptosis in vitro. Moreover, anesthesia with 1.4% isoflurane for two hours potentiated, whereas the anesthesia with 0.7% isoflurane for 30 minutes attenuated, the Aβ-induced caspase-3 activation in vivo. The high concentration isoflurane potentiated the Aβ-induced reduction in Bcl-2/Bax ratio and caused a robust elevation of cytosolic calcium levels. The low concentration isoflurane attenuated the Aβ-induced reduction in Bcl-2/Bax ratio and caused only a mild elevation of cytosolic calcium levels. These results suggest that isoflurane may have dual effects (protection or promotion) on Aβ-induced toxicity, which potentially act through the Bcl-2 family proteins and cytosolic calcium. These findings would lead to more systematic studies to determine the potential dual effects of anesthetics on AD-associated neurotoxicity.
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Affiliation(s)
- Zhipeng Xu
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129-2060, USA
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Nociceptive stimuli enhance anesthetic-induced neuroapoptosis in the rat developing brain. Neurobiol Dis 2012; 45:743-50. [DOI: 10.1016/j.nbd.2011.10.021] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 10/04/2011] [Accepted: 10/22/2011] [Indexed: 11/22/2022] Open
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Isoflurane preconditioning protects astrocytes from oxygen and glucose deprivation independent of innate cell sex. J Neurosurg Anesthesiol 2012; 23:335-40. [PMID: 21908987 DOI: 10.1097/ana.0b013e3182161816] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND Isoflurane exposure can protect the mammalian brain from subsequent insults such as ischemic stroke. However, this protective preconditioning effect is sexually dimorphic, with isoflurane preconditioning decreasing male while exacerbating female brain damage in a mouse model of cerebral ischemia. Emerging evidence suggests that innate cell sex is an important factor in cell death, with brain cells having sex-specific sensitivities to different insults. We used an in vitro model of isoflurane preconditioning and ischemia to test the hypothesis that isoflurane preconditioning protects male astrocytes while having no effect or even a deleterious effect in female astrocytes after subsequent oxygen and glucose deprivation (OGD). METHODS Sex-segregated astrocyte cultures derived from postnatal day 0 to 1 mice were allowed to reach confluency before being exposed to either 0% (sham preconditioning) or 3% isoflurane preconditioning for 2 hours. Cultures were then returned to normal growth conditions for 22 hours before undergoing 10 hours of OGD. Twenty-four hours after OGD, cell viability was quantified using a lactate dehydrogenase assay. RESULTS Isoflurane preconditioning increased cell survival after OGD compared with sham preconditioning independent of innate cell sex. CONCLUSION More studies are needed to determine how cell type and cell sex may impact on anesthetic preconditioning and subsequent ischemic outcomes in the brain.
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Jiang H, Huang Y, Xu H, Sun Y, Han N, Li QF. Hypoxia inducible factor-1α is involved in the neurodegeneration induced by isoflurane in the brain of neonatal rats. J Neurochem 2011; 120:453-60. [PMID: 22097881 DOI: 10.1111/j.1471-4159.2011.07589.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
More and more data show isoflurane, a commonly used volatile anesthetic has dual effects on neuron fate. However, the underlying mechanisms that can explain the apparent paradox are poorly understood. Hypoxia inducible factor (HIF)-1α, a transcription factor, has been found regulating both prosurvival and prodeath pathways in the CNS. Previously, we found that isoflurane can activate HIF-1α under normoxic conditions in vitro and HIF-1α has been found to be involved in the pre-conditioning effect of isoflurane in various organs. Here, we investigated whether HIF-1α is a contributing factor in the neurodegenration in rodent primary cultured neurons and in developing rat brain. Isoflurane dose-dependently induced apoptotic neurodegeneration in neonatal rats as assessed by S100β, cleaved caspase 3 and poly-(ADP-ribose) polymerase (PARP), respectively. Notably, isoflurane up-regulates HIF-1α protein levels in vivo and in vitro during induction of neurodegeneration. Likewise, isoflurane resulted in a significant elevation of cytosonic calcium levels in neuron cultures. Furthermore, knockdown of HIF-1α expression in cultured neurons attenuated isoflurane-induced neurotoxicity. Finally, Morris water maze (MWM) test showed neonatal exposure to isoflurane impaired juvenile learning and memory ability in rats. These findings indicate that HIF-1α is involved in the neurodegeneration induced by isoflurane in the brain of neonatal rats, suggesting HIF-1α may be a candidate for the dual effects of isoflurane on neuron fate.
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Affiliation(s)
- Hong Jiang
- Department of Anesthesiology, Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Dallasen RM, Bowman JD, Xu Y. Isoflurane does not cause neuroapoptosis but reduces astroglial processes in young adult mice. Med Gas Res 2011; 1:27. [PMID: 22146123 PMCID: PMC3253045 DOI: 10.1186/2045-9912-1-27] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 11/03/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Isoflurane, a volatile anesthetic widely used clinically, has been implicated to be both neuroprotective and neurotoxic. The claim about isoflurane causing neural apoptosis remains controversial. In this study, we investigated the effects of isoflurane exposures on apoptotic and anti-apoptotic signals, cell proliferation and neurogenesis, and astroglial processes in young adult mouse brains. METHODS Sixty 6-week-old mice were randomly assigned to four anesthetic concentration groups (0 as control and 0.6%, 1.3%, and 2%) with four recovery times (2 h and 1, 6, and 14 d) after 2-h isoflurane exposure. Immunohistochemistry measurements of activated caspase-3 and Bcl-xl for apoptotic and anti-apoptotic signals, respectively, glial fibrillary acidic protein (GFAP) and vimentin for reactive astrocytosis, doublecortin (Dcx) for neurogenesis, and BrdU for cell proliferation were performed. RESULTS Contrary to the previous conclusion derived from studies with neonatal rodents, we found no evidence of isoflurane-induced apoptosis in the adult mouse brain. Neurogenesis in the subgranule zone of the dentate gyrus was not affected by isoflurane. However, there is a tendency of reduced cell proliferation after 2% isoflurane exposure. VIM and GFAP staining showed that isoflurane exposure caused a delayed reduction of astroglial processes in the hippocampus and dentate gyrus. CONCLUSION Two-hour exposure to isoflurane did not cause neuroapoptosis in adult brains. The delayed reduction in astroglial processes after isoflurane exposure may explain why some volatile anesthetics can confer neuroprotection after experimental stroke because reduced glial scarring facilitates better long-term neuronal recoveries.
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Affiliation(s)
- Renee M Dallasen
- Department of Anesthesiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA.
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Johnsen D, Murphy SJ. Isoflurane preconditioning protects neurons from male and female mice against oxygen and glucose deprivation and is modulated by estradiol only in neurons from female mice. Neuroscience 2011; 199:368-74. [PMID: 21985935 DOI: 10.1016/j.neuroscience.2011.09.053] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 09/22/2011] [Accepted: 09/25/2011] [Indexed: 11/19/2022]
Abstract
The volatile anesthetic, isoflurane, can protect the brain if administered before an insult such as an ischemic stroke. However, this protective "preconditioning" response to isoflurane is specific to males, with females showing an increase in brain damage following isoflurane preconditioning and subsequent focal cerebral ischemia. Innate cell sex is emerging as an important player in neuronal cell death, but its role in the sexually dimorphic response to isoflurane preconditioning has not been investigated. We used an in vitro model of isoflurane preconditioning and ischemia (oxygen and glucose deprivation, OGD) to test the hypotheses that innate cell sex dictates the response to isoflurane preconditioning and that 17β-estradiol attenuates any protective effect from isoflurane preconditioning in neurons via nuclear estrogen receptors. Sex-segregated neuron cultures derived from postnatal day 0-1 mice were exposed to either 0% or 3% isoflurane preconditioning for 1 h. In separate experiments, 17β-estradiol and the non-selective estrogen receptor antagonist ICI 182,780 were added 24 h before preconditioning and then removed at the end of the preconditioning period. Twenty-three hours after preconditioning, all cultures underwent 2 h of OGD. Twenty-four hours following OGD, cell viability was quantified using calcein-AM fluorescence. We observed that isoflurane preconditioning increased cell survival following subsequent OGD regardless of innate cell sex, but that the presence of 17β-estradiol before and during isoflurane preconditioning attenuated this protection only in female neurons independent of nuclear estrogen receptors. We also found that independent of preconditioning treatment, female neurons were less sensitive to OGD compared with male neurons and that transient treatment with 17β-estradiol protected both male and female neurons from subsequent OGD. More studies are needed to determine how cell type, cell sex, and sex steroids like 17β-estradiol may impact on anesthetic preconditioning and subsequent ischemic outcomes in the brain.
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Affiliation(s)
- D Johnsen
- Department of Anesthesiology and Perioperative Medicine, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Mail Code: UHN-2, Portland, OR 97239, USA
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