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Fan P, Lu Y, Wei H, Wang K, Jia P, Zhang Y, Zhang Y, Wang T, Yang L, Zhao J, Zhang S, Lu H, Chen X, Liu Y, Zhang P. Metformin attenuates sevoflurane-induced neurogenesis damage and cognitive impairment: involvement of the Nrf2/G6PD pathway. Metab Brain Dis 2023; 38:2037-2053. [PMID: 37119382 DOI: 10.1007/s11011-023-01218-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 04/17/2023] [Indexed: 05/01/2023]
Abstract
Anesthetics such as sevoflurane are commonly administered to infants and children. However, the possible neurotoxicity caused by prolonged or repetitive exposure to it should be a concern. The neuroprotective effects of metformin are observed in many models of neurological disorders. In this study, we investigated whether metformin could reduce the developmental neurotoxicity induced by sevoflurane exposure in neonatal rats and the potential mechanism. Postnatal day 7 (PND 7) Sprague-Dawley rats and neural stem cells (NSCs) were treated with normal saline or metformin before sevoflurane exposure. The Morris water maze (MWM) was used to observe spatial memory and learning at PND 35-42. Immunofluorescence staining was used to detect neurogenesis in the subventricular zone (SVZ) of the lateral ventricle and the subgranular zone (SGZ) of the dentate gyrus at PND 14. MTT assays, immunofluorescence staining, and TUNEL staining were used to assess the viability, proliferation, differentiation, and apoptosis of NSCs. Western blotting and ELISA were used to assess the protein expression of cleaved caspase-3, nuclear factor erythroid 2-related factor 2 (Nrf2), and glucose-6-phosphate dehydrogenase (G6PD) pathway-related molecules. Exposure to sevoflurane resulted in late cognitive defects, impaired neurogenesis in both the SVZ and SGZ, reduced NSC viability and proliferation, increased NSC apoptosis, and decreased protein expression of G6PD in vitro. Metformin pretreatment attenuated sevoflurane-induced cognitive functional decline and neurogenesis inhibition. Metformin pretreatment also increased the protein expression of Nrf2 and G6PD. However, treatment with the Nrf2 inhibitor, ML385 or the G6PD inhibitor, dehydroepiandrosterone (DHEA) reversed the protective effect of metformin on sevoflurane-induced NSC damage in vitro. Our findings suggested that metformin could reduce sevoflurane-induced neurogenesis damage and neurocognitive defects in the developing rat brain by influencing the Nrf2/G6PD signaling pathways.
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Affiliation(s)
- Pei Fan
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Yuying Lu
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Haidong Wei
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Kui Wang
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Pengyu Jia
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Yuanyuan Zhang
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Yan Zhang
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Tianyue Wang
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Liufei Yang
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Jing Zhao
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China
| | - Shuyue Zhang
- Institute of Neurobiology, National Key Academic Subject of Physiology, Xi'an Jiaotong University, 76 # Yanta West Road, Xi'an, Shaanxi, 710061, China
| | - Haixia Lu
- Institute of Neurobiology, National Key Academic Subject of Physiology, Xi'an Jiaotong University, 76 # Yanta West Road, Xi'an, Shaanxi, 710061, China
| | - Xinlin Chen
- Institute of Neurobiology, National Key Academic Subject of Physiology, Xi'an Jiaotong University, 76 # Yanta West Road, Xi'an, Shaanxi, 710061, China
| | - Yong Liu
- Institute of Neurobiology, National Key Academic Subject of Physiology, Xi'an Jiaotong University, 76 # Yanta West Road, Xi'an, Shaanxi, 710061, China
| | - Pengbo Zhang
- Department of Anesthesiology, The Second Affiliated Hospital, Xi'an Jiaotong University, 157 # West 5 road, Xi'an, Shaanxi, 710004, China.
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Wu N, Liu H, Lv X, Sun Y, Jiang H. Neobaicalein prevents isoflurane anesthesia-induced cognitive impairment in neonatal mice via regulating CREB1. Clinics (Sao Paulo) 2023; 78:100201. [PMID: 37120983 PMCID: PMC10173397 DOI: 10.1016/j.clinsp.2023.100201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 03/24/2023] [Accepted: 04/04/2023] [Indexed: 05/02/2023] Open
Abstract
OBJECTIVES Isoflurane (ISO) is widely used in the clinic and research. The authors aimed to explore whether Neobaicalein (Neob) could protect neonatal mice from ISO-induced cognitive damage. METHOD The open field test, Morris water maze test, and tail suspension test was performed to assess the cognitive function in mice. Enzyme-linked immunosorbent assay was used to evaluate inflammatory-related protein concentrations. Immunohistochemistry was used to assess Ionized calcium-Binding Adapter molecule-1 (IBA-1) expression. Hippocampal neuron viability was detected using the Cell Counting Kit-8 assay. Double immunofluorescence staining was employed to confirm the interaction between proteins. Western blotting was used to assess protein expression levels. RESULTS Neob notably improved cognitive function and exhibited anti-inflammatory effects; moreover, under iso-treatment, it exhibited neuroprotective effects. Furthermore, Neob suppressed interleukin-1β, tumor necrosis factor-α, and interleukin-6 levels and upregulated interleukin-10 levels in ISO-treated mice. Neob significantly mitigated iso-induced increases in IBA-1-positive cell numbers of the hippocampus in neonatal mice. Furthermore, it inhibited ISO-induced neuronal apoptosis. Mechanistically, Neob was observed to upregulate cAMP Response Element Binding protein (CREB1) phosphorylation and protected hippocampal neurons from ISO-mediated apoptosis. Moreover, it rescued ISO-induced abnormalities of synaptic protein. CONCLUSIONS Neob prevented ISO anesthesia-induced cognitive impairment by suppressing apoptosis and inflammation through upregulating CREB1.
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Affiliation(s)
- Niming Wu
- Department of Anesthesiology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hua Liu
- Department of Anesthesiology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiang Lv
- Department of Anesthesiology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yu Sun
- Department of Anesthesiology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hong Jiang
- Department of Anesthesiology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Zhong J, Lu Z, Fang B, Chen C, Jiang Y. A potential involvement of LCN2 in isoflurane-induced postoperative cognitive dysfunction. Mol Cell Toxicol 2023. [DOI: 10.1007/s13273-023-00333-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Feng Y, Wang K, Wang N, Jia P, Zhang L, Yuan H, Lu P, Lu Y, Zhang H, Li R, Zhang Y, Li Q, Zhang P. Tetramethylpyrazine protects neural stem cells against sevoflurane-induced toxicity through Akt/GSK-3β pathway. Metab Brain Dis 2022; 37:2457-2466. [PMID: 35838869 DOI: 10.1007/s11011-022-01008-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 05/16/2022] [Indexed: 11/28/2022]
Abstract
Sevoflurane, a commonly used anesthetic, has been found to cause neural stem cell (NSC) injury, thereby contributing to neurocognitive impairment following general anesthesia. Tetramethylpyrazine (TMP), one of the most widely used medicinal compounds isolated from a traditional Chinese herb, possess neuroprotective activity. However, its effect on sevoflurane-induced NSC injury remains unclear. NSCs were pretreated with indicated concentrations of TMP for 2 h and then exposed to sevoflurane for 6 h. Cell injury was measured using lactate dehydrogenase (LDH) release assay. Cell viability and proliferation were detected by cell counting kit-8 (CCK-8) assay and 5-bromo-2'-deoxyuridine (BrdU) labeling, respectively. Apoptotic cells were detected using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The levels of cleaved caspase-3, phosphorylated protein kinase B (Akt) and phosphorylated glycogen synthase kinase-3β (GSK-3β) were detected by western blotting. Our results showed exposure to sevoflurane decreased the viability and proliferation of NSCs, while TMP preserved NSC viability and proliferation after sevoflurane exposure. In addition, the expression of cleaved caspase-3 and TUNEL positive cells were markedly decreased in TMP-treated NSCs compared with the control. Furthermore, pretreatment with TMP significantly increased the levels of phosphorylated Akt and GSK-3β in sevoflurane-injured NSCs. However, an upstream inhibitor of Akt, LY294002 abolished the protective of TMP on the cell viability of NSCs. In conclusion, these findings indicate that TMP protects NSCs from sevoflurane-induced toxicity through Akt/GSK-3β pathway.
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Affiliation(s)
- Yan Feng
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
- Department of Anesthesiology, Xi'an People's Hospital (Xi'an Fourth Hospital), 710004, Xi'an, Shaanxi, China
| | - Kui Wang
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Ning Wang
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Pengyu Jia
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Lei Zhang
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
- Department of Anesthesiology, Xi'an People's Hospital (Xi'an Fourth Hospital), 710004, Xi'an, Shaanxi, China
| | - Haozheng Yuan
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Pan Lu
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Yang Lu
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Hong Zhang
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Rong Li
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Yan Zhang
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Qianqian Li
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China
| | - Pengbo Zhang
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, 157# West 5 Road, 710004, Xi'an, Shaanxi, China.
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Mineshima H, Kimoto H, Hitomi M, Akizawa F, Terayama Y, Yoshikawa T. Comparative study on detectability of learning and memory disorder between two water maze tests commonly used in juvenile rat toxicity studies using isoflurane inhaled rat model. Congenit Anom (Kyoto) 2022; 62:96-104. [PMID: 35133039 DOI: 10.1111/cga.12460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/13/2021] [Accepted: 12/24/2021] [Indexed: 11/29/2022]
Abstract
Evaluation of learning and memory is crucial in juvenile animal toxicity studies (JAS) during the development of CNS active drugs, but there are no currently recommended test methods. We compared the ability of the Morris water maze (MWM) and the Biel water maze (BWM) to detect learning and memory disorder (LMD) using rats inhaled isoflurane (IFN). Rats were treated with 1% IFN using inhalation on postnatal day (PND) 7 for 6 h. All rats were subjected to the MWM on PND 33 and the BWM on PND 55/57 (Experiment 1), or the BWM on PND 32/33 and the MWM on PND 54/55 (Experiment 2). On PND 70, the brain was weighed and then neurohistopathology was conducted. There were no IFN-related changes in clinical signs and body weight. In the tests beginning on PND 32/33, the MWM clearly detected IFN-related LMD in both sexes whereas the BWM detected LMD only in males. With an additional benefit of a simpler procedure, the MWM was considered superior to the BMW for JAS. LMD was not detected in both mazes tested from PND 54/55/57, which was considered due to weak effect and/or recovery of brain function with growth. Single IFN inhalation on PND 7 was considered useful as positive control to induce LMD caused by postnatal exposure in rats, but stronger treatment regimens was recommended.
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Affiliation(s)
- Hiroshi Mineshima
- Department of Drug Safety Research, Nonclinical Research Center, Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan
| | - Hiroki Kimoto
- Department of Drug Safety Research, Nonclinical Research Center, Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan
| | - Masaya Hitomi
- Department of Drug Safety Research, Nonclinical Research Center, Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan
| | - Fumika Akizawa
- Department of Drug Safety Research, Nonclinical Research Center, Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan
| | - Yui Terayama
- Department of Drug Safety Research, Nonclinical Research Center, Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan
| | - Tsuyoshi Yoshikawa
- Department of Drug Safety Research, Nonclinical Research Center, Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan
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Neonatal Anesthesia and Oxidative Stress. Antioxidants (Basel) 2022; 11:antiox11040787. [PMID: 35453473 PMCID: PMC9026345 DOI: 10.3390/antiox11040787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/13/2022] [Accepted: 04/14/2022] [Indexed: 02/04/2023] Open
Abstract
Neonatal anesthesia, while often essential for surgeries or imaging procedures, is accompanied by significant risks to redox balance in the brain due to the relatively weak antioxidant system in children. Oxidative stress is characterized by concentrations of reactive oxygen species (ROS) that are elevated beyond what can be accommodated by the antioxidant defense system. In neonatal anesthesia, this has been proposed to be a contributing factor to some of the negative consequences (e.g., learning deficits and behavioral abnormalities) that are associated with early anesthetic exposure. In order to assess the relationship between neonatal anesthesia and oxidative stress, we first review the mechanisms of action of common anesthetic agents, the key pathways that produce the majority of ROS, and the main antioxidants. We then explore the possible immediate, short-term, and long-term pathways of neonatal-anesthesia-induced oxidative stress. We review a large body of literature describing oxidative stress to be evident during and immediately following neonatal anesthesia. Moreover, our review suggests that the short-term pathway has a temporally limited effect on oxidative stress, while the long-term pathway can manifest years later due to the altered development of neurons and neurovascular interactions.
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Li C, Liu S, Mei Y, Wang Q, Lu X, Li H, Tao F. Differential Effects of Sevoflurane Exposure on Long-Term Fear Memory in Neonatal and Adult Rats. Mol Neurobiol 2022; 59:2799-2807. [PMID: 35201592 DOI: 10.1007/s12035-021-02629-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/29/2021] [Indexed: 10/19/2022]
Abstract
It remains unclear whether exposure to sevoflurane produces different effects on long-term cognitive function in developing and mature brains. In the present study, Sprague-Dawley neonatal rats at postnatal day (PND) 7 and adult rats (PND 56) were used in all experiments. We performed fear conditioning testing to examine long-term fear memory following 4-h sevoflurane exposure. We assessed hippocampal synapse ultrastructure with a transmission electron microscope. Moreover, we investigated the effect of sevoflurane exposure on the expression of postsynaptic protein 95 (PSD-95) and its binding protein kalirin-7 in the hippocampus. We observed that early exposure to sevoflurane in neonatal rats impairs hippocampus-dependent fear memory, reduces hippocampal synapse density, and dramatically decreases the expressions of PSD-95 and kalirin-7 in the hippocampus of the developing brain. However, sevoflurane exposure in adult rats has no effects on hippocampus-dependent fear memory and hippocampal synapse density, and the expressions of PSD-95 and kalirin-7 in the adult hippocampus are not significantly altered following sevoflurane treatment. Our results indicate that sevoflurane exposure produces differential effects on long-term fear memory in neonatal and adult rats and that PSD-95 signaling may be involved in the molecular mechanism for early sevoflurane exposure-caused long-term fear memory impairment.
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Affiliation(s)
- Changsheng Li
- Department of Anesthesiology and Perioperative Medicine, Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Henan International Joint Laboratory of Anesthesiology and Perioperative Cognitive Function, Zhengzhou, Henan, China
| | - Sufang Liu
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, 3302 Gaston Ave, Dallas, TX, 75023, USA
| | - Yixin Mei
- Department of Anesthesiology and Perioperative Medicine, Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Qingyong Wang
- Department of Neurology, University of Chinese Academy of Sciences-Shenzhen Hospital, Shenzhen, China
| | - Xihua Lu
- Department of Anesthesiology and Perioperative Medicine, Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Hongle Li
- Department of Molecular Pathology, Affiliated Cancer Hospital of Zhengzhou University, 127 Dongming Road, Zhengzhou, Henan, 450008, China.
| | - Feng Tao
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, 3302 Gaston Ave, Dallas, TX, 75023, USA.
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Liu Y, Yang H, Fu Y, Pan Z, Qiu F, Xu Y, Yang X, Chen Q, Ma D, Liu Z. TRPV1 Antagonist Prevents Neonatal Sevoflurane-Induced Synaptic Abnormality and Cognitive Impairment in Mice Through Regulating the Src/Cofilin Signaling Pathway. Front Cell Dev Biol 2021; 9:684516. [PMID: 34307363 PMCID: PMC8293754 DOI: 10.3389/fcell.2021.684516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 06/14/2021] [Indexed: 11/13/2022] Open
Abstract
Long-term neurodevelopmental disorders following neonatal anesthesia have been reported both in young animals and in children. The activation of transient receptor potential vanilloid 1 (TRPV1) channels in hippocampus adversely affects neurodevelopment. The current study explored the underlying mechanism of TRPV1 channels on long-lasting cognitive dysfunction induced by anesthetic exposure to the developing brain. we demonstrated that TRPV1 expression was increased after sevoflurane exposure both in vitro and in vivo. Sevoflurane exposure to hippocampal neurons decreased the synaptic density and the surface GluA1 expression, as well as increased co-localization of internalized AMPAR in early and recycling endosomes. Sevoflurane exposure to newborn mice impaired learning and memory in adulthood, and reduced AMPAR subunit GluA1, 2 and 3 expressions in the crude synaptosomal fractions from mouse hippocampus. The inhibition of TRPV1 reversed the phenotypic changes induced by sevoflurane. Moreover, sevoflurane exposure increased Src phosphorylation at tyrosine 416 site thereby reducing cofilin phosphorylation. TRPV1 blockade reversed these suppressive effects of sevoflurane. Our data suggested that TRPV1 antagonist may protect against synaptic damage and cognitive dysfunction induced by sevoflurane exposure during the brain developing stage.
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Affiliation(s)
- Yuqiang Liu
- Department of Anesthesiology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Han Yang
- Department of Anesthesiology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Yifei Fu
- Department of Anesthesiology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Zhenglong Pan
- Department of Anesthesiology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Fang Qiu
- Department of Anesthesiology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Yanwen Xu
- Shenzhen Key Laboratory of Neurosurgery, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Xinping Yang
- Department of Anesthesiology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Qian Chen
- Division of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom
| | - Daqing Ma
- Division of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom
| | - Zhiheng Liu
- Department of Anesthesiology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
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Neudecker V, Perez-Zoghbi JF, Brambrink AM. Recent advances in understanding cognitive and behavioural alterations after early-in-life anaesthesia exposure and new mitigation/alternative strategies in preclinical studies. Curr Opin Anaesthesiol 2021; 34:402-408. [DOI: 10.1097/aco.0000000000001016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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10
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Lee JR, Joseph B, Hofacer RD, Upton B, Lee SY, Ewing L, Zhang B, Danzer SC, Loepke AW. Effect of dexmedetomidine on sevoflurane-induced neurodegeneration in neonatal rats. Br J Anaesth 2021; 126:1009-1021. [PMID: 33722372 DOI: 10.1016/j.bja.2021.01.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 01/12/2021] [Accepted: 01/20/2021] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Structural brain abnormalities in newborn animals after prolonged exposure to all routinely used general anaesthetics have raised substantial concerns for similar effects occurring in millions of children undergoing surgeries annually. Combining a general anaesthetic with non-injurious sedatives may provide a safer anaesthetic technique. We tested dexmedetomidine as a mitigating therapy in a sevoflurane dose-sparing approach. METHODS Neonatal rats were randomised to 6 h of sevoflurane 2.5%, sevoflurane 1% with or without three injections of dexmedetomidine every 2 h (resulting in 2.5, 5, 10, 25, 37.5, or 50 μg kg-1 h-1), or fasting in room air. Heart rate, oxygen saturation, level of hypnosis, and response to pain were measured during exposure. Neuronal cell death was quantified histologically after exposure. RESULTS Sevoflurane at 2.5% was more injurious than at 1% in the hippocampal cornu ammonis (CA)1 and CA2/3 subfields; ventral posterior and lateral dorsal thalamic nuclei; prefrontal, retrosplenial, and somatosensory cortices; and subiculum. Although sevoflurane 1% did not provide complete anaesthesia, supplementation with dexmedetomidine dose dependently increased depth of anaesthesia and diminished responses to pain. The combination of sevoflurane 1% and dexmedetomidine did not reliably reduce neuronal apoptosis relative to an equianaesthetic dose of sevoflurane 2.5%. CONCLUSIONS A sub-anaesthetic dose of sevoflurane combined with dexmedetomidine achieved a level of anaesthesia comparable with that of sevoflurane 2.5%. Similar levels of anaesthesia caused comparable programmed cell death in several developing brain regions. Depth of anaesthesia may be an important factor when comparing the neurotoxic effects of different anaesthetic regimens.
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Affiliation(s)
- Jeong-Rim Lee
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul
| | - Bernadin Joseph
- Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | | | - Brian Upton
- Medical Scientist Training Program, University of Cincinnati, Cincinnati, OH, USA
| | - Samuel Y Lee
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center and University of Cincinnati, Cincinnati, OH, USA
| | - Loren Ewing
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center and University of Cincinnati, Cincinnati, OH, USA
| | - Bingqing Zhang
- Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Steve C Danzer
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center and University of Cincinnati, Cincinnati, OH, USA
| | - Andreas W Loepke
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia and Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
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Abstract
BACKGROUND General anesthetics influence mitochondrial homeostasis, placing individuals with mitochondrial disorders and possibly carriers of recessive mitochondrial mutations at increased risk of perioperative complications. In Drosophila, mutations in the ND23 subunit of complex I of the mitochondrial electron transport chain-analogous to mammalian NDUFS8-replicate key characteristics of Leigh syndrome, an inherited mitochondrial disorder. The authors used the ND23 mutant for testing the hypothesis that anesthetics have toxic potential in carriers of mitochondrial mutations. METHODS The authors exposed wild-type flies and ND23 mutant flies to behaviorally equivalent doses of isoflurane or sevoflurane in 5%, 21%, or 75% oxygen. The authors used percent mortality (mean ± SD, n ≥ 3) at 24 h after exposure as a readout of toxicity and changes in gene expression to investigate toxicity mechanisms. RESULTS Exposure of 10- to 13-day-old male ND23 flies to isoflurane in 5%, 21%, or 75% oxygen resulted in 16.0 ± 14.9% (n = 10), 48.2 ± 16.1% (n = 9), and 99.2 ± 2.0% (n = 10) mortality, respectively. Comparable mortality was observed in females. In contrast, under the same conditions, mortality was less than 5% for all male and female groups exposed to sevoflurane, except 10- to 13-day-old male ND23 flies with 9.6 ± 8.9% (n = 16) mortality. The mortality of 10- to 13-day-old ND23 flies exposed to isoflurane was rescued by neuron- or glia-specific expression of wild-type ND23. Isoflurane and sevoflurane differentially affected expression of antioxidant genes in 10- to 13-day-old ND23 flies. ND23 flies had elevated mortality from paraquat-induced oxidative stress compared with wild-type flies. The mortality of heterozygous ND23 flies exposed to isoflurane in 75% oxygen increased with age, resulting in 54.0 ± 19.6% (n = 4) mortality at 33 to 39 days old, and the percent mortality varied in different genetic backgrounds. CONCLUSIONS Mutations in the mitochondrial complex I subunit ND23 increase susceptibility to isoflurane-induced toxicity and to oxidative stress in Drosophila. Asymptomatic flies that carry ND23 mutations are sensitized to hyperoxic isoflurane toxicity by age and genetic background. EDITOR’S PERSPECTIVE
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Li T, Huang Z, Wang X, Zou J, Tan S. Role of the GABAA receptors in the long-term cognitive impairments caused by neonatal sevoflurane exposure. Rev Neurosci 2020; 30:869-879. [PMID: 31145696 DOI: 10.1515/revneuro-2019-0003] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Accepted: 03/29/2019] [Indexed: 02/06/2023]
Abstract
Sevoflurane is a widely used inhalational anesthetic in pediatric surgeries, which is considered reasonably safe and reversible upon withdrawal. However, recent preclinical studies suggested that peri-neonatal sevoflurane exposure may cause developmental abnormalities in the brain. The present review aimed to present and discuss the accumulating experimental data regarding the undesirable effects of sevoflurane on brain development as revealed by the laboratory studies. First, we summarized the long-lasting side effects of neonatal sevoflurane exposure on cognitive functions. Subsequently, we presented the structural changes, namely, neuroapoptosis, neurogenesis and synaptogenesis, following sevoflurane exposure in the immature brain. Finally, we also discussed the potential mechanisms underlying subsequent cognitive impairments later in life, which are induced by neonatal sevoflurane exposure and pointed out potential strategies for mitigating sevoflurane-induced long-term cognitive impairments. The type A gamma-amino butyric acid (GABAA) receptor, the main targets of sevoflurane, is excitatory rather than inhibitory in the immature neurons. The excitatory effects of the GABAA receptors have been linked to increased neuroapoptosis, elevated serum corticosterone levels and epigenetic modifications following neonatal sevoflurane exposure in rodents, which might contribute to sevoflurane-induced long-term cognitive abnormalities. We proposed that the excitatory GABAA receptor-mediated HPA axis activity might be a novel mechanism underlying sevoflurane-induced long-term cognitive impairments. More studies are needed to investigate the effectiveness and mechanisms by targeting the excitatory GABAA receptor as a prevention strategy to alleviate cognitive deficits induced by neonatal sevoflurane exposure in future.
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Affiliation(s)
- Tao Li
- Grade 2015 of Clinical Medicine, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical College, University of South China, Hengyang 421001, Hunan Province, China
| | - Zeyi Huang
- Department of Histology and Embryology, Institute of Clinical Anatomy & Reproductive Medicine, Hengyang Medical College, University of South China, Hengyang 421001, Hunan Province, China
| | - Xianwen Wang
- Grade 2015 of Clinical Medicine, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical College, University of South China, Hengyang 421001, Hunan Province, China
| | - Ju Zou
- Department of Parasitology, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical College, University of South China, Hengyang 421001, Hunan Province, China
| | - Sijie Tan
- Department of Histology and Embryology, Institute of Clinical Anatomy & Reproductive Medicine, Hengyang Medical College, University of South China, Hengyang 421001, Hunan Province, China
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13
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Chinn GA, Sasaki Russell JM, Banh ET, Lee SC, Sall JW. Voluntary Exercise Rescues the Spatial Memory Deficit Associated With Early Life Isoflurane Exposure in Male Rats. Anesth Analg 2020; 129:1365-1373. [PMID: 31517674 DOI: 10.1213/ane.0000000000004418] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Early life anesthesia exposure results in long-term cognitive deficits in rats. Environmental enrichment consisting of social housing, a stimulating environment, and voluntary exercise can rescue this deficit. We hypothesized that exercise alone is sufficient to rescue the cognitive deficit associated with perinatal anesthesia. METHODS Postnatal day 7 male rats (P7) underwent isoflurane (Iso) or sham exposure and were subsequently weaned at P21. They were then singly housed in a cage with a running wheel or a fixed wheel. After 3 weeks of exercise, animals underwent behavioral testing for spatial and recognition memory assessments. Animals were killed at various time points to accomplish either bromodeoxyuridine (BrdU) labeling or quantitative real-time polymerase chain reaction (qRT-PCR) to quantify brain-derived neurotrophic factor (BDNF) messenger ribonucleic acid (mRNA) levels. RESULTS Postweaning voluntary exercise rescued the long-term spatial memory deficit associated with perinatal Iso exposure. Iso-sedentary animals did not discriminate the goal quadrant, spending no more time than chance during the Barnes maze probe trial (1-sample t test, P = .524) while all other groups did (1-sample t test, PIso-exercise = .033; Pcontrol [Con]-sedentary = .004). We did not find a deficit in recognition memory tasks after Iso exposure as we observed previously. BrdU incorporation in the adult hippocampus of Iso-sedentary animals was decreased compared to sedentary controls (Tukey P = .005). Exercise prevented this decrease, with Iso-exercise animals having more proliferation than Iso-sedentary (Tukey P < .001). There was no effect of exercise or Iso on BDNF mRNA in either the cortex or hippocampus (cortex: FExercise[1,32] = 0.236, P = .631; FIso [1,32] = 0.038, P = .847; FInteraction [1,32] = 1.543, P = .223; and hippocampus: FExercise[1,33] = 1.186, P = .284; FIso [1,33] = 1.46, P = .236; FInteraction[1,33] = 1.78, P = .191). CONCLUSIONS Exercise restores BrdU incorporation and rescues a spatial memory deficit after early life anesthesia exposure. This demonstrates sufficiency of exercise alone in the context of environmental enrichment to recover a behavioral phenotype after a perinatal insult.
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Affiliation(s)
- Gregory A Chinn
- From the Department of Anesthesia and Perioperative Care, University of California, San Francisco, San Francisco, California
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14
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Hypoxia, hypercarbia, and mortality reporting in studies of anaesthesia-related neonatal neurodevelopmental delay in rodent models. Eur J Anaesthesiol 2020; 37:70-84. [DOI: 10.1097/eja.0000000000001105] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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15
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Xu J, Xu M, Wang Y, Mathena RP, Wen J, Zhang P, Furmanski O, Mintz CD. Anesthetics disrupt growth cone guidance cue sensing through actions on the GABA A α2 receptor mediated by the immature chloride gradient. Neurotoxicol Teratol 2019; 74:106812. [PMID: 31251980 DOI: 10.1016/j.ntt.2019.106812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/25/2019] [Accepted: 06/24/2019] [Indexed: 01/17/2023]
Abstract
BACKGROUND General anesthetics (GAs) may exert harmful effects on the developing brain by disrupting neuronal circuit formation. Anesthetics that act on γ-aminobutyric acid (GABA) receptors can interfere with axonal growth cone guidance, a critical process in the assembly of neuronal circuitry. Here we investigate the mechanism by which isoflurane prevents sensing of the repulsive guidance cue, Semaphorin 3A (Sema3A). METHODS Growth cone sensing was assayed by measuring growth cone collapse in dissociated neocortical cultures exposed to recombinant Sema3A in the presence or absence of isoflurane and/or a panel of reagents with specific actions on components of the GABA receptor and chloride ion systems. RESULTS Isoflurane exposure prevents Sema3A induced growth cone collapse. A GABAA α2 specific agonist replicates this effect (36.83 ± 3.417% vs 70.82 ± 2.941%, in the Sema3A induced control group, p < 0.0001), but an α1-specific agonist does not. Both a Na-K-Cl cotransporter 1 antagonism (bumetanide, BUM) and a chloride ionophore (IONO) prevent isoflurane from disrupting growth cone sensing of Sema3A. (65.67 ± 3.775% in Iso + BUM group vs 67.45 ± 3.624% in Sema3A induced control group, 65.34 ± 1.678% in Iso + IONO group vs 68.71 ± 2.071% in Sema3A induced control group, no significant difference) (n = 96 growth cones per group). CONCLUSION Our data suggest that the effects of isoflurane on growth cone sensing are mediated by the α2 subunit of the GABAA receptor and also that they are dependent on the developmental chloride gradient, in which Cl- exhibits a depolarizing effect. These findings provide a rationale for why immature neurons are particularly susceptible to anesthetic toxicity.
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Affiliation(s)
- Jing Xu
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi, 710004, China; Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Michael Xu
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - YuChia Wang
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - R Paige Mathena
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jieqiong Wen
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi, 710004, China; Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Pengbo Zhang
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi, 710004, China
| | - Orion Furmanski
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - C David Mintz
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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16
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Sevoflurane induces cognitive impairment in young mice via autophagy. PLoS One 2019; 14:e0216372. [PMID: 31107909 PMCID: PMC6527218 DOI: 10.1371/journal.pone.0216372] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 04/18/2019] [Indexed: 11/19/2022] Open
Abstract
Background Anesthesia may induce neurotoxicity and neurocognitive impairment in young mice. However, the underlying mechanism remains largely to be determined. Meanwhile, autophagy is involved in brain development and contributes to neurodegenerative diseases. We, therefore, set out to determine the effects of sevoflurane on autophagy in the hippocampus of young mice and on cognitive function in the mice. Methods Six day-old mice received 3% sevoflurane, for two hours daily, on postnatal days (P) 6, 7 and 8. We then decapitated the mice and harvested the hippocampus of the young mice at P8. The level of LC3, the ratio of LC3-II to LC3-I, and SQSTM1/p62 level associated with the autophagy in the hippocampus of the mice were assessed by using Western blotting. We used different groups of mice for behavioral testing via the Morris Water Maze from P31 to P37. Results The anesthetic sevoflurane increased the level of LC3-II and ratio of LC3-II/LC3-I, decreased the p62 level in the hippocampus of the young mice, and induced cognitive impairment in the mice. 3-Methyladenine, the inhibitor of autophagy, attenuated the activation of autophagy and ameliorated the cognitive impairment induced by sevoflurane in the young mice. Conclusion These data showed that sevoflurane anesthesia might induce cognitive impairment in the young mice via activation of autophagy in the hippocampus of the young mice. These findings from the proof of concept studies have established a system and suggest the role of autophagy in anesthesia neurotoxicity and cognitive impairment in the young mice, pending further investigation.
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17
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Maloney SE, Yuede CM, Creeley CE, Williams SL, Huffman JN, Taylor GT, Noguchi KN, Wozniak DF. Repeated neonatal isoflurane exposures in the mouse induce apoptotic degenerative changes in the brain and relatively mild long-term behavioral deficits. Sci Rep 2019; 9:2779. [PMID: 30808927 PMCID: PMC6391407 DOI: 10.1038/s41598-019-39174-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 01/18/2019] [Indexed: 11/22/2022] Open
Abstract
Epidemiological studies suggest exposures to anesthetic agents and/or sedative drugs (AASDs) in children under three years old, or pregnant women during the third trimester, may adversely affect brain development. Evidence suggests lengthy or repeated AASD exposures are associated with increased risk of neurobehavioral deficits. Animal models have been valuable in determining the type of acute damage in the developing brain induced by AASD exposures, as well as in elucidating long-term functional consequences. Few studies examining very early exposure to AASDs suggest this may be a critical period for inducing long-term functional consequences, but the impact of repeated exposures at these ages has not yet been assessed. To address this, we exposed mouse pups to a prototypical general anesthetic, isoflurane (ISO, 1.5% for 3 hr), at three early postnatal ages (P3, P5 and P7). We quantified the acute neuroapoptotic response to a single versus repeated exposure, and found age- and brain region-specific effects. We also found that repeated early exposures to ISO induced subtle, sex-specific disruptions to activity levels, motor coordination, anxiety-related behavior and social preference. Our findings provide evidence that repeated ISO exposures may induce behavioral disturbances that are subtle in nature following early repeated exposures to a single AASD.
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Affiliation(s)
- Susan E Maloney
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Psychology, University of Missouri - St. Louis, St. Louis, MO, 63121, USA
- Intellectual and Developmental Disabilities Research Center, Washington University, St. Louis, MO, USA
| | - Carla M Yuede
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Catherine E Creeley
- Department of Psychology, State University of New York at Fredonia, Fredonia, NY, 14063, USA
| | - Sasha L Williams
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Jacob N Huffman
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - George T Taylor
- Department of Psychology, University of Missouri - St. Louis, St. Louis, MO, 63121, USA
| | - Kevin N Noguchi
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Intellectual and Developmental Disabilities Research Center, Washington University, St. Louis, MO, USA
| | - David F Wozniak
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, 63110, USA.
- Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA.
- Intellectual and Developmental Disabilities Research Center, Washington University, St. Louis, MO, USA.
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18
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Lee JR, Lin EP, Hofacer RD, Upton B, Lee SY, Ewing L, Joseph B, Loepke AW. Alternative technique or mitigating strategy for sevoflurane-induced neurodegeneration: a randomized controlled dose-escalation study of dexmedetomidine in neonatal rats. Br J Anaesth 2019; 119:492-505. [PMID: 28969315 DOI: 10.1093/bja/aex219] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2017] [Indexed: 12/26/2022] Open
Abstract
Background Brain injury in newborn animals from prolonged anaesthetic exposure has raised concerns for millions of children undergoing anaesthesia every yr. Alternative anaesthetic techniques or mitigating strategies are urgently needed to ameliorate potentially harmful effects. We tested dexmedetomidine, both as a single agent alternative technique and as a mitigating adjuvant for sevoflurane anaesthesia. Methods Neonatal rats were randomized to three injections of dexmedetomidine (5, 25, 50, or 100 µg kg -1 every 2 h), or 6 h of 2.5% sevoflurane as a single agent without or with dexmedetomidine (1, 5, 10, or 20 µg kg -1 every 2 h). Heart rate, oxygen saturation, level of consciousness, and response to pain were assessed. Cell death was quantified in several brain regions. Results Dexmedetomidine provided lower levels of sedation and pain control than sevoflurane. Exposure to either sevoflurane or dexmedetomidine alone did not cause mortality, but the combination of 2.5% sevoflurane and dexmedetomidine in doses exceeding 1 µg kg -1 did. Sevoflurane increased apoptosis in all brain regions; supplementation with dexmedetomidine exacerbated neuronal injury, potentially as a result of ventilatory or haemodynamic compromise. Dexmedetomidine by itself increased apoptosis only in CA2/3 and the ventral posterior nucleus, but not in prefrontal cortex, retrosplenial cortex, somatosensory cortex, subiculum, lateral dorsal thalamic nucleaus, or hippocampal CA1. Conclusions We confirm previous findings of sevoflurane-induced neuronal injury. Dexmedetomidine, even in the highest dose, did not cause similar injury, but provided lesser degrees of anaesthesia and pain control. No mitigation of sevoflurane-induced injury was observed with dexmedetomidine supplementation, suggesting that future studies should focus on anaesthetic-sparing effects of dexmedetomidine, rather than injury-preventing effects.
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Affiliation(s)
- J-R Lee
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul 120-752, Korea
| | - E P Lin
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - R D Hofacer
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Program in Neuroscience, University of Cincinnati, Cincinnati, OH, USA
| | - B Upton
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Medical Scientist Training Program, University of Cincinnati, Cincinnati, OH, USA
| | - S Y Lee
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - L Ewing
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - B Joseph
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - A W Loepke
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Program in Neuroscience, University of Cincinnati, Cincinnati, OH, USA.,Departments of Anesthesiology and Pediatrics, University of Cincinnati, Cincinnati, OH, USA.,Department of Anesthesiology and Critical Care Medicine, Division of Cardiac Anesthesiology, Children's Hospital of Philadelphia and University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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19
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Bajwa NM, Lee JB, Halavi S, Hartman RE, Obenaus A. Repeated isoflurane in adult male mice leads to acute and persistent motor decrements with long-term modifications in corpus callosum microstructural integrity. J Neurosci Res 2018; 97:332-345. [DOI: 10.1002/jnr.24343] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 09/28/2018] [Accepted: 09/28/2018] [Indexed: 12/24/2022]
Affiliation(s)
- Nikita M. Bajwa
- Musculoskeletal Disease Center; VA Loma Linda Healthcare System; Loma Linda California
| | - Jeong B. Lee
- Department of Basic Sciences, School of Medicine; Loma Linda University; Loma Linda California
| | - Shina Halavi
- Department of Psychology, School of Behavioral Health; Loma Linda University; Loma Linda California
| | - Richard E. Hartman
- Department of Psychology, School of Behavioral Health; Loma Linda University; Loma Linda California
| | - Andre Obenaus
- Department of Basic Sciences, School of Medicine; Loma Linda University; Loma Linda California
- Department of Pediatrics, School of Medicine; University of California; Irvine California
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20
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Li B, Feng XJ, Hu XY, Chen YP, Sha JC, Zhang HY, Fan HG. Effect of melatonin on attenuating the isoflurane-induced oxidative damage is related to PKCα/Nrf2 signaling pathway in developing rats. Brain Res Bull 2018; 143:9-18. [PMID: 30278199 DOI: 10.1016/j.brainresbull.2018.09.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 09/13/2018] [Accepted: 09/27/2018] [Indexed: 11/30/2022]
Abstract
Isoflurane, an inhalational anesthesia, has frequently been used in pediatric anesthesia. However, research indicates that isoflurane can induce oxidative stress and affect neural and cognitive development. Melatonin, an endogenous hormone that exhibits antioxidant functions, can play a neuroprotective role by activating the PKCα/Nrf2 signaling pathway in response to oxidative stress. This study aims to determine whether the effect of melatonin on isoflurane-induced oxidative stress is related to activation of the PKCα/Nrf2 signaling pathway. Rat pups at postnatal day 7 were treated with control or 1.5% isoflurane for 4 h after pretreatment for 15 min with either melatonin (10 mg/kg i.p.) or 1% ethanol. The hematoxylin and eosin staining and transmission electron microscopic examination were used for observation of histopathology. The oxidative stress-related indicators were detected by using assay kits. The western blotting, immunohistochemistry and immunofluorescence were used to detect the activation of PKCα/Nrf2 signaling pathway. Results showed that isoflurane induced nerve damage in the hippocampus, and melatonin could reduce this injury. Oxidative stress-related indicators suggested that isoflurane can significantly increase reactive oxygen species and malondialdehyde levels, and decrease superoxide dismutase and glutathione activity compared with the control group, whereas melatonin ameliorated these indices. Expression of proteins associated with the PKCα/Nrf2 signaling pathway indicated that the neuroprotective effect of melatonin is related to activation of the PKCα/Nrf2 signaling pathway. These results suggest that the attenuating effect of melatonin on isoflurane-induced oxidative stress is related to activation of the PKCα/Nrf2 signaling pathway. These findings promote further research into underlying mechanisms and effective treatments to attenuate anesthesia neurotoxicity.
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Affiliation(s)
- Bei Li
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Xiu Jing Feng
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Xue Yuan Hu
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Yong Ping Chen
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Ji Chen Sha
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Hua Yun Zhang
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Hong-Gang Fan
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
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O'Farrell RA, Foley AG, Buggy DJ, Gallagher HC. Neurotoxicity of Inhalation Anesthetics in the Neonatal Rat Brain: Effects on Behavior and Neurodegeneration in the Piriform Cortex. Anesthesiol Res Pract 2018; 2018:6376090. [PMID: 30018637 PMCID: PMC6029509 DOI: 10.1155/2018/6376090] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 05/08/2018] [Indexed: 11/17/2022] Open
Abstract
There is concern that clinical use of anesthetic drugs may cause neurotoxicity in the developing brain and subsequent abnormal neurobehavior. We therefore evaluated neurotoxic effects of inhalation anesthetics in the neonatal rat brain, using in vivo histological and neurobehavioral outcomes. Wistar rats (n=79, postnatal day 15) were subjected to a clinically relevant single exposure of urethane, isoflurane, sevoflurane, or placebo, without surgery. At 48 h and 96 h, behavioral parameters were recorded and the animals were sacrificed. In cryosectioned brains, total cells and dying cells in layer II of the piriform cortex were counted using unbiased stereology. At 48 h, cell numbers in layer II of the piriform cortex of all drug-treated animals were reduced versus controls (p=0.01). The effect persisted at 96 h in isoflurane- and urethane-exposed animals. Piriform cortical layer II neurons undergoing degeneration, detected histologically by pyknotic nuclei and eosinophilic cytoplasm, were increased in the animals treated with isoflurane (1.9 ± 0.7 at 96 h) and urethane (2.4 ± 0.8 at 96 h) versus sevoflurane (0.8 ± 0.3 at 96 h) and controls (0.9 ± 0.2 at 96 h). Sevoflurane- and isoflurane-treated animals exhibited increased activity and decreased suckling compared with controls, and sevoflurane-exposed animals also displayed increased rearing behavior at both timepoints.
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Affiliation(s)
- Rachel A. O'Farrell
- Department of Anaesthesia, Mater Misericordiae University Hospital, Eccles Street, Dublin 7, Ireland
- School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
- Bon Secours Hospital, Glasnevin, Dublin 9, Ireland
| | - Andrew G. Foley
- Berand Neuropharmacology, NovaUCD, University College Dublin, Belfield Innovation Park, Dublin 4, Ireland
| | - Donal J. Buggy
- Department of Anaesthesia, Mater Misericordiae University Hospital, Eccles Street, Dublin 7, Ireland
- School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
- Outcomes Research Consortium, Cleveland Clinic, Cleveland, OH, USA
| | - Helen C. Gallagher
- School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
- UCD-Mater Clinical Research Centre, Eccles Street, Dublin 7, Ireland
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Maloney SE, Creeley CE, Hartman RE, Yuede CM, Zorumski CF, Jevtovic-Todorovic V, Dikranian K, Noguchi KK, Farber NB, Wozniak DF. Using animal models to evaluate the functional consequences of anesthesia during early neurodevelopment. Neurobiol Learn Mem 2018; 165:106834. [PMID: 29550366 DOI: 10.1016/j.nlm.2018.03.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 02/16/2018] [Accepted: 03/13/2018] [Indexed: 12/15/2022]
Abstract
Fifteen years ago Olney and colleagues began using animal models to evaluate the effects of anesthetic and sedative agents (ASAs) on neurodevelopment. The results from ongoing studies indicate that, under certain conditions, exposure to these drugs during development induces an acute elevated apoptotic neurodegenerative response in the brain and long-term functional impairments. These animal models have played a significant role in bringing attention to the possible adverse effects of exposing the developing brain to ASAs when few concerns had been raised previously in the medical community. The apoptotic degenerative response resulting from neonatal exposure to ASAs has been replicated in many studies in both rodents and non-human primates, suggesting that a similar effect may occur in humans. In both rodents and non-human primates, significantly increased levels of apoptotic degeneration are often associated with functional impairments later in life. However, behavioral deficits following developmental ASA exposure have not been consistently reported even when significantly elevated levels of apoptotic degeneration have been documented in animal models. In the present work, we review this literature and propose a rodent model for assessing potential functional deficits following neonatal ASA exposure with special reference to experimental design and procedural issues. Our intent is to improve test sensitivity and replicability for detecting subtle behavioral effects, and thus enhance the translational significance of ASA models.
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Affiliation(s)
- Susan E Maloney
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Intellectual and Developmental Disabilities Research Center, Washington University, St. Louis, MO, USA
| | - Catherine E Creeley
- Department of Psychology, The State University of New York at Fredonia, Fredonia, NY 14063, USA
| | - Richard E Hartman
- Department of Psychology, Loma Linda University, 11130 Anderson St., Loma Linda, CA 92354, USA
| | - Carla M Yuede
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Charles F Zorumski
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Krikor Dikranian
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
| | - Kevin K Noguchi
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Intellectual and Developmental Disabilities Research Center, Washington University, St. Louis, MO, USA
| | - Nuri B Farber
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Intellectual and Developmental Disabilities Research Center, Washington University, St. Louis, MO, USA
| | - David F Wozniak
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA; Intellectual and Developmental Disabilities Research Center, Washington University, St. Louis, MO, USA.
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Gao J, Luo A, Yan J, Fang X, Tang X, Zhao Y, Li S. Mdivi-1 pretreatment mitigates isoflurane-induced cognitive deficits in developmental rats. Am J Transl Res 2018; 10:432-443. [PMID: 29511437 PMCID: PMC5835808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 01/06/2018] [Indexed: 06/08/2023]
Abstract
Accumulating evidence indicates that general anesthetics can cause acute neuroapoptosis and long-term cognitive deficit in models exposed to anesthetics during the brain growth-spurt period. Anesthetics-induced imbalance of mitochondrial fusion and fission preceded and contributed to developmental neuroapoptosis. Accordingly, the imbalance was accompanied by activation of dynamin-related protein (Drp)1 which was closely associated with synaptic degeneration in neurodegenerative diseases. Based on the neuroprotective role of mitochondrial division inhibitor-1 (mdivi-1) in neurodegeneration and stroke, we set out to examine whether mdivi-1 can mitigate developmental neurotoxicity induced by isoflurane. In the present study, we showed that 2% isoflurane exposure for 2 h triggered Drp1 dephosphorylation at serine 656 and increased translocation of Drp1 and Bax from cytosol to mitochondria, concomitant with cytochrome C leakage into the cytosol. Remarkably, pretreatment with mdivi-1 not only alleviated isoflurane-induced disturbed mitochondrial translocation of Drp1 and Bax and almost restored morphological changes, but also inhibited cytochrome C release, caspase9 and caspase3 activation in hippocampi. Furthermore, mdivi-1 mitigated the loss of synaptic proteins and long-lasting cognitive deficit in later life of rats neonatally exposed to isoflurane. Taken together, isoflurane-induced Drp1 activation and translocation led to excessive mitochondrial fission and subsequently contributed to the synaptic injury and long-term cognitive impairment. However, mdivi-1 pretreatment prevented Drp1-dependent excessive mitochondrial fission and mitigated neuro-apoptosis and synaptic injury, and improved the long-term cognitive function. Thus mdivi-1 holds far-reaching insight for prophylaxis of developmental neurotoxicity induced by isoflurane.
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Affiliation(s)
- Jie Gao
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology1095 Jiefang Avenue, Wuhan 430030, Hubei, China
| | - Ailin Luo
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology1095 Jiefang Avenue, Wuhan 430030, Hubei, China
| | - Jing Yan
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology1095 Jiefang Avenue, Wuhan 430030, Hubei, China
| | - Xi Fang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology1095 Jiefang Avenue, Wuhan 430030, Hubei, China
| | - Xiaole Tang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology1095 Jiefang Avenue, Wuhan 430030, Hubei, China
| | - Yilin Zhao
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology1095 Jiefang Avenue, Wuhan 430030, Hubei, China
| | - Shiyong Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology1095 Jiefang Avenue, Wuhan 430030, Hubei, China
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Role of α7nAChR-NMDAR in sevoflurane-induced memory deficits in the developing rat hippocampus. PLoS One 2018; 13:e0192498. [PMID: 29401517 PMCID: PMC5798850 DOI: 10.1371/journal.pone.0192498] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 01/24/2018] [Indexed: 11/28/2022] Open
Abstract
Detrimental effects of volatile anaesthetics, including sevoflurane, on the structure and function of the developing brain have been reported. The internalization of N-methyl-D-aspartate receptors (NMDARs) contributes to anaesthetic neurotoxicity. Both nicotinic acetylcholine receptors (nAChRs) and NMDAR play a critical role in the development of the nervous system. Moreover, nAChR can interact with NMDAR, and previous studies have demonstrated modulation of NMDAR by nAChR. In our study, we used an α7 nicotinic acetylcholine receptor (α7nAChR) agonist and α7nAChR antagonist to explore the role of α7nAChR and NMDAR in sevoflurane-induced long-term effects on memory and dendritic spine both in vivo and in vitro. The results revealed that the activation of α7nAChR attenuated the development of sevoflurane-induced memory deficit and dendritic spine changes, which might be by regulating NR2B-containing NMDAR trafficking from the intracellular pool to the cell surface pool in the hippocampus. Moreover, we demonstrated that α7nAChR could regulate NR2B-containing NMDAR via Src-family tyrosine kinase (SFK). Thus, our current study indicates that the trafficking of NR2B-containing NMDAR is regulated by α7nAChR via SFK in neonatal rat hippocampus, which may be secondary to sevoflurane-induced cognitive deficits in the developing hippocampus.
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Armstrong R, Riaz S, Hasan S, Iqbal F, Rice T, Syed N. Mechanisms of Anesthetic Action and Neurotoxicity: Lessons from Molluscs. Front Physiol 2018; 8:1138. [PMID: 29410627 PMCID: PMC5787087 DOI: 10.3389/fphys.2017.01138] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 12/27/2017] [Indexed: 01/17/2023] Open
Abstract
Anesthesia is a prerequisite for most surgical procedures in both animals and humans. Significant strides have been made in search of effective and safer compounds that elicit rapid induction and recovery from anesthesia. However, recent studies have highlighted possible negative effects of several anesthetic agents on the developing brain. The precise nature of this cytotoxicity remains to be determined mainly due to the complexity and the intricacies of the mammalian brain. Various invertebrates have contributed significantly toward our understanding of how both local and general anesthetics affect intrinsic membrane and synaptic properties. Moreover, the ability to reconstruct in vitro synapses between individually identifiable pre- and postsynaptic neurons is a unique characteristic of molluscan neurons allowing us to ask fundamental questions vis-à-vis the long-term effects of anesthetics on neuronal viability and synaptic connectivity. Here, we highlight some of the salient aspects of various molluscan organisms and their contributions toward our understanding of the fundamental mechanisms underlying the actions of anesthetic agents as well as their potential detrimental effects on neuronal growth and synaptic connectivity. We also present some novel preliminary data regarding a newer anesthetic agent, dexmedetomidine, and its effects on synaptic transmission between Lymnaea neurons. The findings presented here underscore the importance of invertebrates for research in the field of anesthesiology while highlighting their relevance to both vertebrates and humans.
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Affiliation(s)
- Ryden Armstrong
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Saba Riaz
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Sean Hasan
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Fahad Iqbal
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Tiffany Rice
- Department of Anesthesia, Alberta Children's Hospital, University of Calgary, Calgary, AB, Canada
| | - Naweed Syed
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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Goyagi T. The additional oxygen as a carrier gas during long-duration sevoflurane exposure ameliorate the neuronal apoptosis and improve the long-term cognitive function in neonatal rats. Brain Res 2018; 1678:220-230. [DOI: 10.1016/j.brainres.2017.10.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 10/12/2017] [Accepted: 10/14/2017] [Indexed: 01/31/2023]
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Abstract
BACKGROUND Early postnatal exposure to general anesthetic agents causes a lasting impairment in learning and memory in animal models. One hypothesis to explain this finding is that exposure to anesthetic agents during critical points in neural development disrupts the formation of brain circuitry. Here, we explore the effects of sevoflurane on the neuronal growth cone, a specialization at the growing end of axons and dendrites that is responsible for the targeted growth that underlies connectivity between neurons. METHODS Dissociated neuronal cultures were prepared from embryonic mouse neocortex. Time-lapse images of live growth cones exposed to anesthetics were taken using differential interference contrast microscopy, and the rate of change of the area of the lamellipodia and the speed of the filopodial tip were quantified as measures of motility. The involvement of the p75 neurotropin receptor (p75NTR) was tested using inhibitors applied to the media and by a coimmunoprecipitation assay. RESULTS The rate of lamellipodial area change and filopodial tip velocity in both axonal and dendritic growth cones was significantly reduced with sevoflurane exposure between 2% and 6%. Motility could be substantially restored by treatment with Y27632 and TAT-peptide 5, which are inhibitors of Rho Kinase and p75NTR, respectively. Sevoflurane results in reduced coimmunoprecipitation of Rho-Guanosine-5'-diphosphate dissociation inhibitor after pulldown with p75NTR. CONCLUSIONS Sevoflurane interferes with growth cone motility, which is a critical process in brain circuitry formation. Our data suggest that this may occur through an action on the p75NTR, which promotes growth inhibitory signaling by the Rho pathway.
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Kang E, Jiang D, Ryu YK, Lim S, Kwak M, Gray CD, Xu M, Choi JH, Junn S, Kim J, Xu J, Schaefer M, Johns RA, Song H, Ming GL, Mintz CD. Early postnatal exposure to isoflurane causes cognitive deficits and disrupts development of newborn hippocampal neurons via activation of the mTOR pathway. PLoS Biol 2017; 15:e2001246. [PMID: 28683067 PMCID: PMC5500005 DOI: 10.1371/journal.pbio.2001246] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 06/02/2017] [Indexed: 12/18/2022] Open
Abstract
Clinical and preclinical studies indicate that early postnatal exposure to anesthetics can lead to lasting deficits in learning and other cognitive processes. The mechanism underlying this phenomenon has not been clarified and there is no treatment currently available. Recent evidence suggests that anesthetics might cause persistent deficits in cognitive function by disrupting key events in brain development. The hippocampus, a brain region that is critical for learning and memory, contains a large number of neurons that develop in the early postnatal period, which are thus vulnerable to perturbation by anesthetic exposure. Using an in vivo mouse model we demonstrate abnormal development of dendrite arbors and dendritic spines in newly generated dentate gyrus granule cell neurons of the hippocampus after a clinically relevant isoflurane anesthesia exposure conducted at an early postnatal age. Furthermore, we find that isoflurane causes a sustained increase in activity in the mechanistic target of rapamycin pathway, and that inhibition of this pathway with rapamycin not only reverses the observed changes in neuronal development, but also substantially improves performance on behavioral tasks of spatial learning and memory that are impaired by isoflurane exposure. We conclude that isoflurane disrupts the development of hippocampal neurons generated in the early postnatal period by activating a well-defined neurodevelopmental disease pathway and that this phenotype can be reversed by pharmacologic inhibition. The United States Food and Drug Administration has recently warned that exposure to anesthetic and sedative drugs during the third trimester of prenatal development and during the first 3 years of life may cause lasting impairments in cognitive function. The mechanisms by which this undesirable side effect occurs are unknown. In this manuscript, we present evidence in mice that early developmental exposure to isoflurane, a canonical general anesthetic, disrupts the appropriate development of neurons in the hippocampus, a brain region associated with learning and memory. Isoflurane also causes up-regulation of the mechanistic target of rapamycin (mTOR) pathway, a signaling system that has been associated with other neurodevelopmental cognitive disorders. Treatment with an inhibitor of the mTOR pathway after isoflurane exposure normalizes neuronal development and also ameliorates the impairments in learning induced by isoflurane. We conclude that early exposure to isoflurane can cause learning deficits via actions on the mTOR pathway, and that this mechanism represents a potentially druggable target to minimize the side effects of anesthetics on the developing brain.
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Affiliation(s)
- Eunchai Kang
- Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Danye Jiang
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Yun Kyoung Ryu
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Sanghee Lim
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Minhye Kwak
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Christy D. Gray
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Michael Xu
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Jun H. Choi
- Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Sue Junn
- Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Jieun Kim
- Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Jing Xu
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Michele Schaefer
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Roger A. Johns
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Hongjun Song
- Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- The Solomon Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Guo-Li Ming
- Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- The Solomon Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - C. David Mintz
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail:
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Anesthesia, brain changes, and behavior: Insights from neural systems biology. Prog Neurobiol 2017; 153:121-160. [PMID: 28189740 DOI: 10.1016/j.pneurobio.2017.01.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 01/19/2017] [Accepted: 01/22/2017] [Indexed: 02/08/2023]
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Walters JL, Paule MG. Review of preclinical studies on pediatric general anesthesia-induced developmental neurotoxicity. Neurotoxicol Teratol 2017; 60:2-23. [DOI: 10.1016/j.ntt.2016.11.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 11/16/2016] [Accepted: 11/16/2016] [Indexed: 11/24/2022]
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Kang E, Berg DA, Furmanski O, Jackson WM, Ryu YK, Gray CD, Mintz CD. Neurogenesis and developmental anesthetic neurotoxicity. Neurotoxicol Teratol 2016; 60:33-39. [PMID: 27751818 DOI: 10.1016/j.ntt.2016.10.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 10/05/2016] [Accepted: 10/07/2016] [Indexed: 11/24/2022]
Abstract
The mechanism by which anesthetics might act on the developing brain in order to cause long term deficits remains incompletely understood. The hippocampus has been identified as a structure that is likely to be involved, as rodent models show numerous deficits in behavioral tasks of learning that are hippocampal-dependent. The hippocampus is an unusual structure in that it is the site of large amounts of neurogenesis postnatally, particularly in the first year of life in humans, and these newly generated neurons are critical to the function of this structure. Intriguingly, neurogenesis is a major developmental event that occurs during postulated windows of vulnerability to developmental anesthetic neurotoxicity across the different species in which it has been studied. In this review, we examine the evidence for anesthetic effects on neurogenesis in the early postnatal period and ask whether neurogenesis should be studied further as a putative mechanism of injury. Multiple anesthetics are considered, and both in vivo and in vitro work is presented. While there is abundant evidence that anesthetics act to suppress neurogenesis at several different phases, evidence of a causal link between these effects and any change in learning behavior remains elusive.
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Affiliation(s)
- Eunchai Kang
- Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Daniel A Berg
- Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Orion Furmanski
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - William M Jackson
- Department of Anesthesiology, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Yun Kyoung Ryu
- School of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Christy D Gray
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - C David Mintz
- Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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Lin D, Liu J, Kramberg L, Ruggiero A, Cottrell J, Kass IS. Early-life single-episode sevoflurane exposure impairs social behavior and cognition later in life. Brain Behav 2016; 6:e00514. [PMID: 27688943 PMCID: PMC5036436 DOI: 10.1002/brb3.514] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 05/12/2016] [Accepted: 05/13/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Single-episode anesthetic exposure is the most prevalent surgery-related incidence among young children in the United States. Although numerous studies have used animals to model the effects of neonatal anesthetics on behavioral changes later on in life, our understanding of the functional consequences to the developing brain in a comprehensive and clinically relevant manner is unclear. METHODS The volatile anesthetic, sevoflurane (sevo) was administered to C57BL6 postnatal day 7 (P7) mice in a 40% oxygen and 60% nitrogen gas mixture. In order to examine the effects of sevo alone on the developing brain in a clinically relevant manner, mice were exposed to an average of 2.38 ± 0.11% sevo for 2 h. No sevo (control) mice were treated in an identical manner without sevo exposure. Mice were examined for cognition and neuropsychiatric-like behavioral changes at 1-5 months of age. RESULTS Using the active place avoidance (APA) test and the novel object recognition (NOR) test, we demonstrated that P7 sevo-treated mice showed a deficit in learning and memory both during periadolescence and adulthood. We then employed a battery of neuropsychiatric-like behavioral tests to examine social interaction, communication, and repetitive behavior. Interestingly, compared to the no-sevo-treated group, sevo-treated mice showed significant reductions in the time interacting with a novel mouse (push-crawl and following), time and interaction in a chamber with a novel mouse, and time sniffing a novel social odor. CONCLUSIONS Our study established that single-episode, 2-h sevo treatment during early life impairs cognition later on in life. With this approach, we also observed neuropsychiatric-like behavior changes such as social interaction deficits in the sevo-treated mice. This study elucidated the effects of a clinically relevant single-episode sevo application, given during the neonatal period, on neurodevelopmental behavioral changes later on in life.
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Affiliation(s)
- Daisy Lin
- Anesthesiology Department SUNY Downstate Medical Center Box 6, 450 Clarkson Ave Brooklyn New York 11203; Department of Physiology and Pharmacology SUNY Downstate Medical Center 450 Clarkson Ave Brooklyn New York 11203
| | - Jinyang Liu
- Anesthesiology Department SUNY Downstate Medical Center Box 6, 450 Clarkson Ave Brooklyn New York 11203
| | - Lea Kramberg
- Anesthesiology Department SUNY Downstate Medical Center Box 6, 450 Clarkson Ave Brooklyn New York 11203
| | - Andrea Ruggiero
- Anesthesiology Department SUNY Downstate Medical Center Box 6, 450 Clarkson Ave Brooklyn New York 11203
| | - James Cottrell
- Anesthesiology Department SUNY Downstate Medical Center Box 6, 450 Clarkson Ave Brooklyn New York 11203
| | - Ira S Kass
- Anesthesiology Department SUNY Downstate Medical Center Box 6, 450 Clarkson Ave Brooklyn New York 11203; Department of Physiology and Pharmacology SUNY Downstate Medical Center 450 Clarkson Ave Brooklyn New York 11203; The Robert F. Furchgott Center for Neural and Behavioral Sciences Brooklyn New York 11203
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Aksenov DP, Miller MJ, Li L, Wyrwicz AM. Eyeblink classical conditioning and BOLD fMRI of anesthesia-induced changes in the developing brain. Physiol Behav 2016; 167:10-15. [PMID: 27591109 DOI: 10.1016/j.physbeh.2016.08.030] [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: 05/21/2016] [Revised: 07/21/2016] [Accepted: 08/29/2016] [Indexed: 01/19/2023]
Abstract
Millions of children undergo general anesthesia each year in the USA alone, and a growing body of literature from animals and humans suggests that exposure to anesthesia at an early age can impact neuronal development, leading to learning and memory impairments later in childhood. Although a number of studies have reported behavioral and structural effects of anesthesia exposure during infancy, the functional manifestation of these changes has not been previous examined. In this study we used BOLD fMRI to measure the functional response to stimulation in the whisker barrel cortex of awake rabbits before and after learning a trace eyeblink classical conditioning paradigm. The functional changes, in terms of activated volume and time course, in rabbits exposed to isoflurane anesthesia during infancy was compared to unanesthetized controls when both groups reached young adulthood. Our findings show that whereas both groups exhibited decreased BOLD response duration after learning, the anesthesia-exposed group also showed a decrease in BOLD response volume in the whisker barrel cortex, particularly in the deeper infragranular layer. These results suggest that anesthesia exposure during infancy may affect the intracortical processes that mediate learning-related plasticity.
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Affiliation(s)
| | | | - Limin Li
- NorthShore University HealthSystem, Evanston, IL, 60201, USA
| | - Alice M Wyrwicz
- NorthShore University HealthSystem, Evanston, IL, 60201, USA
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Docosahexaenoic Acid Rescues Synaptogenesis Impairment and Long-Term Memory Deficits Caused by Postnatal Multiple Sevoflurane Exposures. BIOMED RESEARCH INTERNATIONAL 2016; 2016:4062579. [PMID: 27597963 PMCID: PMC4997086 DOI: 10.1155/2016/4062579] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 07/07/2016] [Accepted: 07/12/2016] [Indexed: 02/02/2023]
Abstract
Sevoflurane exposures were demonstrated to induce neurotoxicity in the developing brain in both human and animal studies. However, there is no effective approach to reverse it. The present study aimed to evaluate the feasibility of utilizing docosahexaenoic acid (DHA) to prevent sevoflurane-induced neurotoxicity. P6 (postnatal 6 days) mice were administrated DHA after exposure to 3% sevoflurane for two hours daily in three consecutive days. Molecular expressions of synaptic makers (PSD95, synaptophysin) and synaptic morphological changes were investigated by Western blot analysis and transmission electron microscopy, respectively. Meanwhile, Morris water maze test was used to assess spatial memory of mice at P31 (postnatal 31 days). DHA restored sevoflurane-induced decreased level of PSD95 and synaptophysin expressions and increased PSD areas and also improved long-term spatial memory. These results suggest that DHA could rescue synaptogenesis impairment and long-term memory deficits in postnatal caused by multiple sevoflurane exposures.
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Zalucki O, van Swinderen B. What is unconsciousness in a fly or a worm? A review of general anesthesia in different animal models. Conscious Cogn 2016; 44:72-88. [PMID: 27366985 DOI: 10.1016/j.concog.2016.06.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 05/31/2016] [Accepted: 06/20/2016] [Indexed: 12/14/2022]
Abstract
All animals are rendered unresponsive by general anesthetics. In humans, this is observed as a succession of endpoints from memory loss to unconsciousness to immobility. Across animals, anesthesia endpoints such as loss of responsiveness or immobility appear to require significantly different drug concentrations. A closer examination in key model organisms such as the mouse, fly, or the worm, uncovers a trend: more complex behaviors, either requiring several sub-behaviors, or multiple neural circuits working together, are more sensitive to volatile general anesthetics. This trend is also evident when measuring neural correlates of general anesthesia. Here, we review this complexity hypothesis in humans and model organisms, and attempt to reconcile these findings with the more recent view that general anesthetics potentiate endogenous sleep pathways in most animals. Finally, we propose a presynaptic mechanism, and thus an explanation for how these drugs might compromise a succession of brain functions of increasing complexity.
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Affiliation(s)
- Oressia Zalucki
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Bruno van Swinderen
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
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Hu D, Flick RP, Gleich SJ, Scanlon MM, Zaccariello MJ, Colligan RC, Katusic SK, Schroeder DR, Hanson AC, Buenvenida SL, Wilder RT, Sprung J, Warner DO. Construction and Characterization of a Population-Based Cohort to Study the Association of Anesthesia Exposure with Neurodevelopmental Outcomes. PLoS One 2016; 11:e0155288. [PMID: 27167371 PMCID: PMC4864330 DOI: 10.1371/journal.pone.0155288] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 04/04/2016] [Indexed: 11/20/2022] Open
Abstract
Exposure to general anesthesia at an early age has been associated with adverse neurodevelopmental outcomes in both animal and human studies, but some of these studies employed anesthetic agents that are no longer in clinical use. In this manuscript, we describe the methods used to construct a new population-based study cohort to study the association between early anesthetic exposure and subsequent neurodevelopmental outcomes. A birth cohort of all children born in Olmsted County, MN from January 1, 1996 to December 31, 2000 was identified. For each, school enrollment status in the Independent School District (ISD) 535 at age 5 or 6 and all episodes of anesthetic exposure before age 3 were identified. A study cohort was created by matching children enrolled in ISD 535 based on the propensity of receiving general anesthesia. Three analyses were performed to characterize the study cohort by comparing the birth and parental information, comorbidities, and socioeconomic status. The first analysis compared the characteristics of birth cohort children who were and were not enrolled in ISD 535. The second analysis evaluated the success of the propensity matching schemes in creating groups of children that were similar in measured characteristics except for anesthesia exposure. The third analysis compared the characteristics of children with anesthesia exposures who were and were not included in the final cohort based on propensity matching. Results of these analyses demonstrate only slight differences among the comparison groups, and therefore these are unlikely to compromise our future analysis of anesthetic exposure and neurodevelopmental outcomes.
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Affiliation(s)
- Danqing Hu
- Mayo Graduate School, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Randall P. Flick
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Stephen J. Gleich
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Maura M. Scanlon
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | | | - Robert C. Colligan
- Department of Psychology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Slavica K. Katusic
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Darrell R. Schroeder
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Andrew C. Hanson
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Shonie L. Buenvenida
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Robert T. Wilder
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Juraj Sprung
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - David O. Warner
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail:
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Nyman Y, Fredriksson A, Lönnqvist PA, Viberg H. Etomidate exposure in early infant mice (P10) does not induce apoptosis or affect behaviour. Acta Anaesthesiol Scand 2016; 60:588-96. [PMID: 26763687 DOI: 10.1111/aas.12685] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 11/30/2015] [Accepted: 12/08/2015] [Indexed: 12/21/2022]
Abstract
BACKGROUND Numerous animal studies have shown that all commonly used intravenous anaesthetic drugs and volatile agents may cause neuronal apoptosis following exposure in early life. Most studies have focussed on detecting increased apoptosis but their methods are not always readily transferrable to humans. The lipid formulation of etomidate represents an alternative to the currently established intravenous anaesthetic agents but there is no animal or human data on apoptosis or long-term behavioural changes. The aim of our study was to investigate the effects of etomidate on cerebral neuronal apoptosis and long-term behavioural effects using an established mouse model that represents the clinically relevant period of anaesthesia during early infancy in humans. METHODS Six groups of 10 day old mice (P10) were injected with either etomidate 0.3, 3 or 10 mg/kg, propofol 60 mg/kg, ketamine 50 mg/kg or placebo only. Apoptosis in the cerebral cortex and hippocampus was assessed 24 h after treatment (activated caspase-3). Late behavioural effects were tested at 2 months of age (spontaneous activity in a new environment). RESULTS No evidence was found of differences in activated caspase 3-concentrations among the study groups. Significant late behavioural changes were only observed in the ketamine group. CONCLUSION A single dose of etomidate in early infant mice at P10 did not produce evidence of cerebral apoptosis or impaired adult motor behaviour.
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Affiliation(s)
- Y. Nyman
- Department of Paediatric Anaesthesia and Intensive Care; Astrid Lindgrens Children's Hospital/Karolinska University Hospital; Stockholm Sweden
| | - A. Fredriksson
- Department of Neuroscience, Psychiatry; Uppsala University; Uppsala Sweden
| | - P.-A. Lönnqvist
- Department of Paediatric Anaesthesia and Intensive Care; Astrid Lindgrens Children's Hospital/Karolinska University Hospital; Stockholm Sweden
| | - H. Viberg
- Department of Environmental Toxicology; Uppsala University; Uppsala Sweden
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Ramklass R, Hauser N, Levin AI. Anaesthesia associated developmental neurotoxicity (AADN) 2015. SOUTHERN AFRICAN JOURNAL OF ANAESTHESIA AND ANALGESIA 2016. [DOI: 10.1080/22201181.2015.1126980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Man YG, Zhou RG, Zhao B. Efficacy of rutin in inhibiting neuronal apoptosis and cognitive disturbances in sevoflurane or propofol exposed neonatal mice. Int J Clin Exp Med 2015; 8:14397-14409. [PMID: 26550427 PMCID: PMC4613112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Accepted: 08/03/2015] [Indexed: 06/05/2023]
Abstract
Sevoflurane and propofol are widely used in pediatric anesthesia. Neurotoxicity of sevoflurane and propofol in developing brain has been reported and these effects raise concerns on the usage of the drugs. We investigated the influence of rutin, a flavonoid on the neurodegenerative effects of sevoflurane and propofol and on memory and cognition in neonatal rodent model. Separate groups of neonatal mice (C57BL/6) were administered with rutin at 25 or 50 mg/kg body weight (b.wt) from post natal day 2 (P1) to P21. P7 mice were exposed to 2.9% sevoflurane and/or propofol (150 mg/kg b.wt). Neuroapoptosis was assessed by measuring activated caspase-3 and by Fluoro-Jade C staining. Plasma S100β levels were detected by ELISA. Morris water maze test was performed to test learning and memory impairments in the animals. General behaviour of the mice was also assessed. Anesthesia exposure caused severe neuroapoptosis and also raised the levels of plasma S100β. Neuroapoptosis, memory and cognitive deficits observed following anesthetics were comparatively more profound in mice on exposure to combined drug (sevoflurane and propofol) than in those exposed to either of the anesthetics. Rutin at both the doses was effective in reducing the apoptotic cell counts and enhanced the memory and cognitive abilities. Rutin supplementation offered significant protection against anesthetic induced neurodegeneration and learning and memory disturbances.
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Affiliation(s)
- Yi-Gang Man
- Department of Children's Nervous and Rehabilitation, Jining No. 1 People's Hospital Jining 272111, Shandong, China
| | - Rui-Gang Zhou
- Department of Children's Nervous and Rehabilitation, Jining No. 1 People's Hospital Jining 272111, Shandong, China
| | - Bing Zhao
- Department of Children's Nervous and Rehabilitation, Jining No. 1 People's Hospital Jining 272111, Shandong, China
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Toxic and protective effects of inhaled anaesthetics on the developing animal brain: systematic review and update of recent experimental work. Eur J Anaesthesiol 2015; 31:669-77. [PMID: 24922049 DOI: 10.1097/eja.0000000000000073] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Accumulating preclinical data indicate that neonatal exposure to general anaesthetics is detrimental to the central nervous system. Some studies, however, display potential protective effects of exactly the same anaesthetic agents on the immature brain. The effects of inhaled anaesthetics on the developing brain have received close attention from researchers, clinicians and the public in recent decades. OBJECTIVES To summarise the preclinical evidence reported in the last 5 years on both the deleterious effects and the neuroprotective potential in special indications, of inhaled anaesthetics on the developing brain. DESIGN A systematic review. DATA SOURCES PubMed search performed in June 2013. ELIGIBILITY CRITERIA Search terms included brain, development, inhaled anaesthetic, toxicity and protection within the scope of the last 5 years with animals. The reference lists of relevant articles and recent reviews were also hand-searched for additional studies. The type, dose and exposure duration of anaesthetics, species and age of animals, histopathologic indicators, outcomes and affected brain areas, neuro developmental test modules and outcomes, as well as other outcomes and comments were summarised. RESULTS Two hundred and nineteen relevant titles were initially revealed. In total, 81 articles were identified, with 68 articles assessing the detrimental effects induced by inhaled anaesthetics in the immature brain along with possible treatments. The remaining 13 articles focused on the protective profile of inhaled anaesthetics on perinatal hypoxic-ischaemic brain injury. Administration of inhaled anaesthetic agents to the immature brain was shown to be deleterious in several preclinical studies. In perinatal hypoxic-ischaemic brain injury models, pre- and postconditioning of inhalational anaesthetics exerted neuroprotective effects. CONCLUSION The majority of studies have linked inhaled anaesthetics to toxic effects in the neonatal brain of rodents, piglets and primates. Only a few studies, however, could demonstrate long-lasting cognitive impairment. The results of inhalational anaesthetic-induced neuroprotection in perinatal hypoxic-ischaemic brain injury are a promising basis for more research in this field. In general, prospective clinical trials are needed to further differentiate the effects of inhaled anaesthetics on the immature brain.
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Isoflurane impairs the capacity of astrocytes to support neuronal development in a mouse dissociated coculture model. J Neurosurg Anesthesiol 2015; 26:363-8. [PMID: 25191957 DOI: 10.1097/ana.0000000000000119] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND There is growing concern that pediatric exposure to anesthetic agents may cause long-lasting deficits in learning by impairing brain development. Most studies to date on this topic have focused on the direct effects of anesthetics on developing neurons. Relatively little attention has been paid to possible effects of anesthetics on astrocytes, a glial cell type that plays an important supporting role in neuronal development. METHODS Astrocytes were exposed to isoflurane and then cocultured with unexposed neurons to test for astrocyte-specific toxic effects on neuronal growth. Axon length was measured in the cocultured neurons to assess neuronal growth. RESULTS We found that neurons cocultured with astrocytes exposed to isoflurane exhibited a 30% reduction in axon outgrowth. Further experimentation showed that this effect is likely due to reduced levels of brain-derived neurotrophic factor in the coculture media. CONCLUSIONS Isoflurane interferes with the ability of cultured astrocytes to support neuronal growth. This finding represents a potentially novel mechanism through which general anesthetics may interfere with brain development.
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Abstract
The results of several retrospective clinical studies suggest that exposure to anesthetic agents early in life is correlated with subsequent learning and behavioral disorders. Although ongoing prospective clinical trials may help to clarify this association, they remain confounded by numerous factors. Thus, some of the most compelling data supporting the hypothesis that a relatively short anesthetic exposure can lead to a long-lasting change in brain function are derived from animal models. The mechanism by which such changes could occur remains incompletely understood. Early studies identified anesthetic-induced neuronal apoptosis as a possible mechanism of injury, and more recent work suggests that anesthetics may interfere with several critical processes in brain development. The function of the mature brain requires the presence of circuits, established during development, which perform the computations underlying learning and cognition. In this review, we examine the mechanisms by which anesthetics could disrupt brain circuit formation, including effects on neuronal survival and neurogenesis, neurite growth and guidance, formation of synapses, and function of supporting cells. There is evidence that anesthetics can disrupt aspects of all of these processes, and further research is required to elucidate which are most relevant to pediatric anesthetic neurotoxicity.
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Goyal R. Animal testing in the history of anesthesia: Now and then, some stories, some facts. J Anaesthesiol Clin Pharmacol 2015; 31:149-51. [PMID: 25948891 PMCID: PMC4411824 DOI: 10.4103/0970-9185.155139] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Rakhee Goyal
- Department of Anesthesia and Critical Care, Armed Forces Medical College and Command Hospital (SC), Pune, Maharashtra, India
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Li G, Xue Q, Luo Y, Hu X, Yu B. S6 inhibition contributes to isoflurane neurotoxicity in the developing brain. Toxicol Lett 2015; 233:102-13. [PMID: 25597859 DOI: 10.1016/j.toxlet.2014.11.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 11/18/2014] [Accepted: 11/21/2014] [Indexed: 02/07/2023]
Abstract
Postnatal isoflurane exposure leads to neurodegeneration and deficits of spatial learning and memory in the adulthood. However, the underlying mechanisms remain unclear. Ribosomal protein S6 is demonstrated to play a pivotal role in control of cell survival, protein synthesis and synaptogenesis for brain development. In this study, the possible role of S6 and its upstream signaling pathways in the developmental neurotoxicity of isoflurane was evaluated using models of primary cultured hippocampal neurons and postnatal day 7 rats. We found that isoflurane decreased IGF-1 level and suppressed activation of IGF-1 receptor, sequentially inhibiting S6 activity via IGF-1/MEK/ERK and IGF-1/PI3K/Akt signaling pathways. S6 inhibition enhanced isoflurane-induced decreased Bcl-xL and increased cleaved caspase-3 and Bad, also reduced PSD95 expression and aggravated deficits of spatial learning and memory. S6 activation could reverse the damages above. These results indicate that S6 inhibition, led by suppression of upstream IGF-1/MEK/ERK and IGF-1/PI3K/Akt signaling pathways, is involved in the neuroapoptosis, synaptogenesis impairment and spatial learning and memory decline caused by postnatal isoflurane exposure. S6 activation may exhibit protective potential against developmental neurotoxicity of isoflurane.
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Affiliation(s)
- Guohui Li
- Department of Anesthesiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China
| | - Qingsheng Xue
- Department of Anesthesiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China
| | - Yan Luo
- Department of Anesthesiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China
| | - Xiaodong Hu
- Department of Anatomy, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China
| | - Buwei Yu
- Department of Anesthesiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China.
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Equipotent Subanesthetic Concentrations of Sevoflurane and Xenon Preventing Cold-stimulated Vocalization of Neonatal Rats. Anesthesiology 2014; 121:1194-202. [DOI: 10.1097/aln.0000000000000423] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Abstract
Background:
The effects of inhaled anesthetics on the developing brain are studied using neonatal rodents exposed to fractions of minimum alveolar concentration (to avoid cardiorespiratory compromise). However, these fractions cannot be assumed to be equipotent. Xenon’s anesthetic and neuroprotective properties warrant investigation in these models. Therefore, equipotent, subanesthetic concentrations of inhaled anesthetics are needed.
Methods:
Forty-eight Wistar rats (Charles River Laboratories, Kent, United Kingdom) on postnatal day 9 were randomized to eight concentrations of inhaled anesthetics: isoflurane, sevoflurane, or xenon. Exposure was closely monitored in individual metal-based chambers resting on a 35°C mat to maintain normothermia. A 25°C mat was used to stimulate vocalization and a sound recording made (1 min, 1 to 100 kHz). Rectal temperature or partial pressure of carbon dioxide and pH of mixed arteriovenous blood were measured immediately after the exposure. Concentration–response models were constructed using logistic regression (dependent variable: vocalization and explanatory variable: concentration). The effects of all other explanatory variables were assessed by inserting them individually into the model.
Results:
The effective inhaled concentrations preventing cold-stimulated vocalization in 50 and 95% of neonatal rats (EiC50 and EiC95) on postnatal day 9 were 0.46 and 0.89% sevoflurane and 20.15 and 34.81% xenon, respectively. The effect on the EiC50 of all other explanatory variables, including duration, was minimal. Stability of EiC50 isoflurane was not achieved over three durations (40, 80, and 120 min exposure). Partial pressure of carbon dioxide and pH in mixed arteriovenous blood appeared normal.
Conclusions:
The authors report equipotent subanesthetic concentrations of sevoflurane and xenon in neonatal rats with preserved cardiopulmonary function. This may be useful in designing neonatal rodent models of anesthesia.
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Anesthesia for the young child undergoing ambulatory procedures: current concerns regarding harm to the developing brain. Curr Opin Anaesthesiol 2014; 26:677-84. [PMID: 24184885 DOI: 10.1097/aco.0000000000000016] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
PURPOSE OF REVIEW Sedation and anesthesia are often necessary for children at any age, and are frequently provided in ambulatory settings. Concerns have mounted, based on both laboratory studies including various mammalian species and retrospective human clinical studies, that the very drugs that induce sedation and anesthesia may trigger an injury in the developing brain, resulting in long-lasting neurobehavioral consequences. RECENT FINDINGS New retrospective studies further augment these concerns. Specifically, recent studies support that a single anesthesia exposure before age 3 may increase the risk for long-term disabilities in language acquisition and abstract reasoning, and that exposure to two or more anesthetics before age 2 nearly doubles the risk for an attention-deficit hyperactivity disorder diagnosis by age 19. However, methodological limitations preclude final conclusions or change in practice based on these reports, as retrospective studies cannot prove causation. Ongoing prospective clinical studies such as 'General Anesthesia and Apoptosis Study', 'Pediatric Anesthesia NeuroDevelopment Assessment', and 'Mayo Safety in Kids' trials will offer more answers in the future. Meanwhile, laboratory experiments continue to describe differential morphologic injury to individual structures in the neuropil, and have identified mitochondrial dysfunction and neuroinflammation as potential links in the injury process. Additionally, concepts for protection against anesthesia-induced neurotoxicity continue to be tested in the laboratory. SUMMARY Results from ongoing prospective clinical trials and translational research will help clarify whether anesthesia-associated neurotoxicity affects the developing human brain, including whether it causes long-term disability, and may further identify the injury mechanisms and potential strategies for protection. Currently, the available evidence does not support a change in practice.
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Lee BH, Chan JT, Hazarika O, Vutskits L, Sall JW. Early exposure to volatile anesthetics impairs long-term associative learning and recognition memory. PLoS One 2014; 9:e105340. [PMID: 25165850 PMCID: PMC4148240 DOI: 10.1371/journal.pone.0105340] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 07/18/2014] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Anesthetic exposure early in life affects neural development and long-term cognitive function, but our understanding of the types of memory that are altered is incomplete. Specific cognitive tests in rodents that isolate different memory processes provide a useful approach for gaining insight into this issue. METHODS Postnatal day 7 (P7) rats were exposed to either desflurane or isoflurane at 1 Minimum Alveolar Concentration for 4 h. Acute neuronal death was assessed 12 h later in the thalamus, CA1-3 regions of hippocampus, and dentate gyrus. In separate behavioral experiments, beginning at P48, subjects were evaluated in a series of object recognition tests relying on associative learning, as well as social recognition. RESULTS Exposure to either anesthetic led to a significant increase in neuroapoptosis in each brain region. The extent of neuronal death did not differ between groups. Subjects were unaffected in simple tasks of novel object and object-location recognition. However, anesthetized animals from both groups were impaired in allocentric object-location memory and a more complex task requiring subjects to associate an object with its location and contextual setting. Isoflurane exposure led to additional impairment in object-context association and social memory. CONCLUSION Isoflurane and desflurane exposure during development result in deficits in tasks relying on associative learning and recognition memory. Isoflurane may potentially cause worse impairment than desflurane.
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Affiliation(s)
- Bradley H. Lee
- Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, California, Unites States of America
| | - John Thomas Chan
- Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, California, Unites States of America
| | - Obhi Hazarika
- Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, California, Unites States of America
| | - Laszlo Vutskits
- Department of Anesthesiology, Pharmacology and Intensive Care, University Hospital of Geneva, Geneva, Switzerland
| | - Jeffrey W. Sall
- Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, California, Unites States of America
- * E-mail:
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Lee BH, Hazarika OD, Quitoriano GR, Lin N, Leong J, Brosnan H, Chan JT, May LDV, Yu D, Alkhamisi A, Stratmann G, Sall JW. Effect of combining anesthetics in neonates on long-term cognitive function. Int J Dev Neurosci 2014; 37:87-93. [PMID: 25003987 DOI: 10.1016/j.ijdevneu.2014.06.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 06/23/2014] [Accepted: 06/27/2014] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND With growing evidence that anesthesia exposure in infancy affects cognitive development, it is important to understand how distinct anesthetic agents and combinations can alter long-term memory. Investigations of neuronal death suggest that combining anesthetic agents increases the extent of neuronal injury. However, it is unclear how the use of simultaneously combined anesthetics affects cognitive outcome relative to the use of a single agent. METHODS Postnatal day 7 (P7) male rats were administered either sevoflurane as a single agent or the combined delivery of sevoflurane with nitrous oxide at 1 Minimum Alveolar Concentration for 4 h. Behavior was assessed in adulthood using the forced alternating T-maze, social recognition, and context-specific object recognition tasks. RESULTS Animals exposed to either anesthetic were unimpaired in the forced alternating T-maze test and had intact social recognition. Subjects treated with the combined anesthetic displayed a deficit, however, in the object recognition task, while those treated with sevoflurane alone were unaffected. CONCLUSION A combined sevoflurane and nitrous oxide anesthetic led to a distinct behavioral outcome compared with sevoflurane alone, suggesting that the simultaneous use of multiple agents may uniquely influence early neural and cognitive development and potentially impacts associative memory.
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Affiliation(s)
- Bradley H Lee
- Department of Anesthesia and Perioperative Care, University of California San Francisco, United States
| | - Obhi D Hazarika
- Department of Anesthesia and Perioperative Care, University of California San Francisco, United States
| | - Gabe R Quitoriano
- University of California San Francisco School of Pharmacy, United States
| | - Nan Lin
- Department of Anesthesiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Jason Leong
- Department of Anesthesia and Perioperative Care, University of California San Francisco, United States
| | - Heather Brosnan
- Department of Anesthesia and Perioperative Care, University of California San Francisco, United States
| | - John T Chan
- Department of Anesthesia and Perioperative Care, University of California San Francisco, United States
| | | | - Damon Yu
- Arizona College of Osteopathic Medicine, United States
| | | | - Greg Stratmann
- Department of Anesthesia and Perioperative Care, University of California San Francisco, United States
| | - Jeffrey W Sall
- Department of Anesthesia and Perioperative Care, University of California San Francisco, United States.
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Wise-Faberowski L, Quinonez ZA, Hammer GB. Anesthesia and the developing brain: relevance to the pediatric cardiac surgery. Brain Sci 2014; 4:295-310. [PMID: 24961762 PMCID: PMC4101478 DOI: 10.3390/brainsci4020295] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 04/02/2014] [Accepted: 04/05/2014] [Indexed: 01/29/2023] Open
Abstract
Anesthetic neurotoxicity has been a hot topic in anesthesia for the past decade. It is of special interest to pediatric anesthesiologists. A subgroup of children potentially at greater risk for anesthetic neurotoxicity, based on a prolonged anesthetic exposure early in development, are those children receiving anesthesia for surgical repair of congenital heart disease. These children have a known risk of neurologic deficit after cardiopulmonary bypass for surgical repair of congenital heart disease. Yet, the type of anesthesia used has not been considered as a potential etiology for their neurologic deficits. These children not only receive prolonged anesthetic exposure during surgical repair, but also receive repeated anesthetic exposures during a critical period of brain development. Their propensity to abnormal brain development, as a result of congenital heart disease, may modify their risk of anesthetic neurotoxicity. This review article provides an overview of anesthetic neurotoxicity from the perspective of a pediatric cardiac anesthesiologist and provides insight into basic science and clinical investigations as it relates to this unique group of children who have been studied over several decades for their risk of neurologic injury.
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Affiliation(s)
- Lisa Wise-Faberowski
- Lucile Packard Children's Hospital, Stanford University School of Medicine, Palo Alto, CA 94305, USA.
| | - Zoel A Quinonez
- Lucile Packard Children's Hospital, Stanford University School of Medicine, Palo Alto, CA 94305, USA.
| | - Gregory B Hammer
- Lucile Packard Children's Hospital, Stanford University School of Medicine, Palo Alto, CA 94305, USA.
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Lee BH, Chan JT, Kraeva E, Peterson K, Sall JW. Isoflurane exposure in newborn rats induces long-term cognitive dysfunction in males but not females. Neuropharmacology 2014; 83:9-17. [PMID: 24704083 DOI: 10.1016/j.neuropharm.2014.03.011] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 03/19/2014] [Accepted: 03/22/2014] [Indexed: 10/25/2022]
Abstract
Volatile anesthetics are used widely for achieving a state of unconsciousness, yet these agents are incompletely understood in their mechanisms of action and effects on neural development. There is mounting evidence that children exposed to anesthetic agents sustain lasting effects on learning and memory. The explanation for these behavioral changes remains elusive, although acute neuronal death after anesthesia is commonly believed to be a principal cause. Rodent models have shown that isoflurane exposure in newborns induces acute neuroapoptosis and long-term cognitive impairment. However, the assessment of predisposing factors is lacking. We investigated the role of sex by delivering isoflurane to postnatal day (P)7 male and female Sprague Dawley rats for 4 h. Brain cell death was assessed 12 h later using FluoroJade C staining in the thalamus, CA1-3 regions of hippocampus, and dentate gyrus. Behavior was assessed separately using a series of object recognition tasks and a test of social memory beginning at P38. We found that isoflurane exposure significantly increased neuronal death in each brain region with no difference between sexes. Behavioral outcome was also equivalent in simple novel object recognition. However, only males were impaired in the recognition of objects in different locations and contexts. Males also exhibited deficient social memory while females were intact. The profound behavioral impairment in males relative to females, in spite of comparable cell death, suggests that males are more susceptible to long-term cognitive effects and this outcome may not be exclusively attributed to neuronal death.
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Affiliation(s)
- Bradley H Lee
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, 513 Parnassus Ave., Box 0542, Med Sci S261, San Francisco, CA 94143, USA
| | - John Thomas Chan
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, 513 Parnassus Ave., Box 0542, Med Sci S261, San Francisco, CA 94143, USA
| | - Ekaterina Kraeva
- University of Arizona College of Medicine, 550 E Van Buren St., Phoenix, AZ 85004, USA
| | | | - Jeffrey W Sall
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, 513 Parnassus Ave., Box 0542, Med Sci S261, San Francisco, CA 94143, USA.
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