title: Hyperglycemia magnifies bupivacaine-induced cell apoptosis triggered by mitochondria dysfunction and endoplasmic reticulum stress.
abstract: Nerve cell injury associated with apoptosis plays an important role in the development of diabetic peripheral neuropathy (DPN). However, it remains unclear whether preexisting or potential neurocyte damage induced by hyperglycemia increases sensitivity to local anesthetics. SH-SY5Y cells were pretreated with a high concentration of glucose in vitro, to imitate DPN prior to administration of bupivacaine or placebo. Cell viability and apoptosis were investigated with a CCK-8 assay and flow cytometry, respectively. In addition, mitochondrial membrane potential, reactive oxygen species (ROS), mitochondrially generated ROS, and activity of mitochondrial complexes I and III were studied to explore the molecular mechanism of bupivacaine-induced mitochondrial injury. Grp78 and caspase-12 expression were measured by qRT-PCR and Western blot, representing endoplasmic reticulum (ER) stress. Cell structure was also assessed via transmission electron microscopy. Incubation with bupivacaine decreased the activity of mitochondrial complexes I and III; increased ROS production at cell and mitochondrial levels, mitochondrial potential depolarization, and Grp78 and caspase-12 expression at both transcription and translation levels; and affected cell structure, which could be enhanced by glucose pretreatment. These findings indicate that mitochondrial dysfunction and ER stress related to ROS are involved in bupivacaine-induced apoptosis and may be enhanced by glucose administration.
authors.affiliation: Department of Anesthesiology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
authors.forename: Le
authors.initials: L
authors.lastname: Li
authors.forename: Xiao-ping
authors.initials: XP
authors.lastname: Ye
authors.forename: Ai-zhu
authors.initials: AZ
authors.lastname: Lu
authors.forename: Shu-qin
authors.initials: SQ
authors.lastname: Zhou
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.forename: Zhong-jie
authors.initials: ZJ
authors.lastname: Liu
authors.forename: Shan
authors.initials: S
authors.lastname: Jiang
authors.forename: Shi-yuan
authors.initials: SY
authors.lastname: Xu
mesh_terms: D000779:Anesthetics, Local / Q000633:toxicity*; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D002045:Bupivacaine / Q000633:toxicity*; D002470:Cell Survival / Q000187:drug effects; D000091342:Endoplasmic Reticulum Chaperone BiP; D059865:Endoplasmic Reticulum Stress / Q000502:physiology*; D005434:Flow Cytometry; D006801:Humans; D006943:Hyperglycemia / Q000150:complications*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects / Q000502:physiology; D046529:Microscopy, Electron, Transmission; D008928:Mitochondria / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D000779:Anesthetics, Local; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D017382:Reactive Oxygen Species; D002045:Bupivacaine