title: Monocarboxylate transporter 4 plays a significant role in the neuroprotective mechanism of ischemic preconditioning in transient cerebral ischemia.
abstract: Monocarboxylate transporters (MCTs), which carry monocarboxylates such as lactate across biological membranes, have been associated with cerebral ischemia/reperfusion process. In this study, we studied the effect of ischemic preconditioning (IPC) on MCT4 immunoreactivity after 5 minutes of transient cerebral ischemia in the gerbil. Animals were randomly designated to four groups (sham-operated group, ischemia only group, IPC + sham-operated group and IPC + ischemia group). A serious loss of neuron was found in the stratum pyramidale of the hippocampal CA1 region (CA1), not CA2/3, of the ischemia-only group at 5 days post-ischemia; however, in the IPC + ischemia groups, neurons in the stratum pyramidale of the CA1 were well protected. Weak MCT4 immunoreactivity was found in the stratum pyramidale of the CA1 in the sham-operated group. MCT4 immunoreactivity in the stratum pyramidale began to decrease at 2 days post-ischemia and was hardly detected at 5 days post-ischemia; at this time point, MCT4 immunoreactivity was newly expressed in astrocytes. In the IPC + sham-operated group, MCT4 immunoreactivity in the stratum pyramidale of the CA1 was increased compared with the sham-operated group, and, in the IPC + ischemia group, MCT4 immunoreactivity was also increased in the stratum pyramidale compared with the ischemia only group. Briefly, present findings show that IPC apparently protected CA1 pyramidal neurons and increased or maintained MCT4 expression in the stratum pyramidale of the CA1 after transient cerebral ischemia. Our findings suggest that MCT4 appears to play a significant role in the neuroprotective mechanism of IPC in the gerbil with transient cerebral ischemia.
authors.affiliation: Department of Surgery, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: Seongkweon
authors.initials: S
authors.lastname: Hong
authors.affiliation: Department of Emergency Medicine, Sacred Heart Hospital, College of Medicine, Hallym University, Anyang, South Korea ; Department of Emergency Medicine, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: Ji Yun
authors.initials: JY
authors.lastname: Ahn
authors.affiliation: Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.
authors.forename: Geum-Sil
authors.initials: GS
authors.lastname: Cho
authors.affiliation: Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: In Hye
authors.initials: IH
authors.lastname: Kim
authors.affiliation: Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: Jeong Hwi
authors.initials: JH
authors.lastname: Cho
authors.affiliation: Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: Ji Hyeon
authors.initials: JH
authors.lastname: Ahn
authors.affiliation: Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: Joon Ha
authors.initials: JH
authors.lastname: Park
authors.affiliation: Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: Moo-Ho
authors.initials: MH
authors.lastname: Won
authors.affiliation: Department of Physiology, College of Medicine, Hallym University, Chuncheon, South Korea.
authors.forename: Bai Hui
authors.initials: BH
authors.lastname: Chen
authors.affiliation: Department of Physiology, College of Medicine, Hallym University, Chuncheon, South Korea.
authors.forename: Bich-Na
authors.initials: BN
authors.lastname: Shin
authors.affiliation: Department of Biomedical Science, Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, South Korea.
authors.forename: Hyun-Jin
authors.initials: HJ
authors.lastname: Tae
authors.affiliation: Department of Emergency Medicine, Sacred Heart Hospital, College of Medicine, Hallym University, Anyang, South Korea ; Department of Emergency Medicine, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: Seung Min
authors.initials: SM
authors.lastname: Park
authors.affiliation: Department of Emergency Medicine, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: Jun Hwi
authors.initials: JH
authors.lastname: Cho
authors.affiliation: Department of Biomedical Science, Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, South Korea.
authors.forename: Soo Young
authors.identifier: 0000-0001-5541-4479
authors.initials: SY
authors.lastname: Choi
authors.affiliation: Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, South Korea.
authors.forename: Jae-Chul
authors.initials: JC
authors.lastname: Lee
keywords: CA1 pyramidal neurons; hippocampus; ischemia/reperfusion injury; ischemic preconditioning; monocarboxylate transporters; nerve regeneration; neural regeneration