Mechanisms of Anesthesia Mediated Neurotoxicity

麻醉介导的神经毒性机制

• 批准号: 9022481
• 负责人: HUAFENG WEI
• 金额: $ 32.35万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-22 至 2018-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9022481
• 关键词: Affect; Age; Anesthesia procedures; Anesthetics; Animals; Apoptosis; Apoptosis Inhibitor; Attention; Autophagocytosis; BCL2 gene; Brain; Brain region; Calcium; Calcium Channel; Calcium Signaling; Cell Culture Techniques; Cell Death; Cell Survival; Cell physiology; Cerebral Ischemia; Cognition; DLG4 gene; Data; Dose; Endoplasmic Reticulum; Event; Excitatory Synapse; FRAP1 gene; General anesthetic drugs; Goals; Health; Hippocampus (Brain); Impaired cognition; Impairment; Inhibitory Synapse; Inositol; Intervention; Isoflurane; Learning; Lithium; Long-Term Effects; Long-Term Potentiation; Measurement; Measures; Mediating; Membrane; Memory; Mitochondria; Modeling; Molecular; Mus; Myocardial Ischemia; Neurons; Nuclear; Patch-Clamp Techniques; Pathway interactions; Propofol; Regulation; Role; Sirolimus; Site; Slice; Staging; Synapses; Synapsins; Synaptic Transmission; Testing; Time; Western Blotting; cell injury; cognitive function; desflurane; gephyrin; inhibitor/antagonist; morris water maze; neuron apoptosis; neuronal survival; neuroprotection; neurotoxic; neurotoxicity; novel; object recognition; patch clamp; patient safety; postsynaptic; presynaptic; receptor; reticulum cell; sevoflurane; synaptic function; tripolyphosphate

DESCRIPTION (provided by applicant): Our recent preliminary studies suggest that the commonly used general anesthetics (GAs), isoflurane and propofol, regulate autophagy via mTOR dependent pathway by activation of InsP3R Ca channel 2+ opening, which contribute to GAs effect on cell survival or death. The overarching goal of this R01 renewal is to investigate the mechanisms of GAs on autophagy activity via activation of InsP3Rs and the subsequent role on cell survival or death, synapse integrity and function and cognitive function. Thus, we hypothesize that GAs modulate autophagy through a dose- and time-dependent activation of InsP3 R, and the magnitude determines the fate of neuronal survival, synaptic integrity and function, and subsequent cognitive function. We have set up three specific aims (SA) to investigate this hypothesis: SA1). We will determine the role of GA-mediated activation of InsP3R subtypes on modulation of autophagy. Using the single channel nuclear patch-clamp technique in cell cultures with various levels of each subtype of InsP3R, we will characterize and compare the activating potency of four GAs (propofol, isoflurane, sevoflurane and desflurane) on each of the three subtypes of InsP3Rs, and correlate patch-clamp data with anesthetics-evoked changes in cytosolic, mitochondrial and ER Ca2+ concentrations. We will study the effects and mechanisms of GAs on autophagy via mTOR dependent pathway using various stimulators and inhibitors and controls of various autophagy regulatory sites in different cell cultures or hippocampus or cortex with different levels of baseline autophagy and InsP3R activity. SA2). We will determine the role of GA-modulated autophagy on apoptosis and synaptic integrity. We will study the effects of GAs on autophagy and apoptosis simultaneously in the same cell cultures and brain regions of mice with varying levels of autophagy and InsP3R baseline activity, in the presence or absence of various autophagy and apoptosis stimulators or inhibitors. We will study the GAs effects on synapse integrity by measuring changes of presynaptic synapsins and postsynaptic markers in primary neuronal cultures or hippocampus and cortex of mice with deficient autophagy or InsP3R-1. SA3). We will determine the role of GA-modulated autophagy on synaptic and cognitive function. We will study the long-term effects of GAs on basic synaptic transmission, long term potentiation (LTP) in hippocampal slices, and cognition in mice with deficient autophagy or InsP3R-1, in the presence or absence of various autophagy and apoptosis stimulators and inhibitors. We will correlate these GAs effects on synapse and cognitive function to their effects on activation of InsP3R, Ca release from the 2+ ER, autophagy activity and related apoptosis and synapse integrity.

描述（由申请人提供）：我们最近的初步研究表明，常用的全身麻醉剂异氟醚和异丙酚通过激活InsP3R Ca通道2+打开mTOR依赖途径调节自噬，从而参与GAs对细胞存活或死亡的影响。这项R01更新的总体目标是研究GAs通过激活InsP3Rs影响自噬活性的机制，以及随后在细胞存活或死亡、突触完整性和功能以及认知功能中的作用。因此，我们假设GAs通过剂量和时间依赖性的insp3r激活来调节自噬，其大小决定了神经元存活、突触完整性和功能以及随后的认知功能的命运。我们设立了三个具体目标（SA）来调查这一假设：我们将确定ga介导的InsP3R亚型激活在自噬调节中的作用。利用单通道核膜片钳技术在具有不同水平的InsP3R亚型的细胞培养中，我们将表征和比较四种气体（异丙酚、异氟烷、七氟烷和地氟烷）对三种InsP3R亚型的激活能力，并将膜片钳数据与麻醉引起的细胞质、线粒体和ER Ca2+浓度的变化相关联。我们将研究GAs通过mTOR依赖途径对自噬的影响和机制，使用各种刺激剂和抑制剂，以及控制不同细胞培养物或海马或皮层中具有不同基线自噬水平和InsP3R活性的各种自噬调节位点。SA2)。我们将确定ga调节的自噬对细胞凋亡和突触完整性的作用。我们将在不同水平的自噬和InsP3R基线活性的小鼠的相同细胞培养和大脑区域中，在存在或不存在各种自噬和凋亡刺激物或抑制剂的情况下，同时研究GAs对自噬和凋亡的影响。我们将通过测量原代神经元培养物或自噬或InsP3R-1缺失小鼠海马和皮质中突触前突触和突触后标记物的变化来研究GAs对突触完整性的影响。SA3)。我们将确定ga调节的自噬对突触和认知功能的作用。我们将研究在存在或不存在各种自噬和凋亡刺激物和抑制剂的情况下，GAs对自噬或InsP3R-1缺陷小鼠的基本突触传递、海马片长期增强（LTP）和认知的长期影响。我们将把这些GAs对突触和认知功能的影响与它们对InsP3R激活、2+ ER中Ca释放、自噬活性和相关凋亡以及突触完整性的影响联系起来。