Attenuated Cerebral Ischemic Injury by Polyethylene Glycol-Conjugated Hemoglobin

( Geum Sil Cho ),( In Young Choi ),( Yoo Keum Choi ),( Seul Ki Kim ),( Ying Cai ),( Kwang Nho ),( Jae Chul Lee ) 한국응용약물학회 2009 Biomolecules & Therapeutics(구 응용약물학회지) Vol.17 No.3

Methyleugenol reduces cerebral ischemic injury by suppression of oxidative injury and inflammation

Choi, Yoo Keum,Cho, Geum-Sil,Hwang, Sunyoung,Kim, Byung Woo,Lim, Ji. H.,Lee, Jae-Chul,Kim, Hyoung Chun,Kim, Won-Ki,Kim, Yeong Sik Informa UK Ltd. 2010 Free radical research Vol.44 No.8

<P>The present study tested the cytoprotective effect of methyleugenol in an <I>in vivo</I> ischemia model (i.e. middle cerebral artery occlusion (MCAO) for 1.5 h and subsequent reperfusion for 24 h) and further investigated its mechanism of action in <I>in vitro</I> cerebral ischemic models. When applied shortly after reperfusion, methyleugenol largely reduced cerebral ischemic injury. Methyleugenol decreased the caspase-3 activation and death of cultured cerebral cortical neurons caused by oxygen-glucose deprivation (OGD) for 1 h and subsequent re-oxygenation for 24 h. Methyleugenol markedly reduced superoxide generation in the ischemic brain and decreased the intracellular oxidative stress caused by OGD/re-oxygenation. It was found that methyleugenol elevated the activities of superoxide dismutase and catalase. Further, methyleugenol inhibited the production of nitric oxide and decreased the protein expression of inducible nitric oxide synthase. Methyleugenol down-regulated the production of pro-inflammatory cytokines in the ischemic brain as well as in immunostimulated mixed glial cells. The results indicate that methyleugenol could be useful for the treatment of ischemia/inflammation-related diseases.</P>

Effect of hyperthermia on calbindin-D 28k immunoreactivity in the hippocampal formation following transient global cerebral ischemia in gerbils

Lee, Jae-Chul,Cho, Jeong-Hwi,Lee, Tae-Kyeong,Kim, In Hye,Won, Moo-Ho,Cho, Geum-Sil,Shin, Bich-Na,Hwang, In Koo,Park, Joon Ha,Ahn, Ji Hyeon,Kang, Il Jun,Lee, Young Joo,Kim, Yang Hee Medknow PublicationsMedia Pvt Ltd 2017 Neural regeneration research Vol.12 No.9

<P>Calbindin D-28K (CB), a Ca<SUP>2+</SUP>-binding protein, maintains Ca<SUP>2+</SUP> homeostasis and protects neurons against various insults. Hyperthermia can exacerbate brain damage produced by ischemic insults. However, little is reported about the role of CB in the brain under hyperthermic condition during ischemic insults. We investigated the effects of transient global cerebral ischemia on CB immunoreactivity as well as neuronal damage in the hippocampal formation under hyperthermic condition using immunohistochemistry for neuronal nuclei (NeuN) and CB, and Fluoro-Jade B histofluorescence staining in gerbils. Hyperthermia (39.5 ± 0.2°C) was induced for 30 minutes before and during transient ischemia. Hyperthermic ischemia resulted in neuronal damage/death in the pyramidal layer of CA1–3 area and in the polymorphic layer of the dentate gyrus at 1, 2, 5 days after ischemia. In addition, hyperthermic ischemia significantly decreaced CB immunoreactivity in damaged or dying neurons at 1, 2, 5 days after ischemia. In brief, hyperthermic condition produced more extensive and severer neuronal damage/death, and reduced CB immunoreactivity in the hippocampus following transient global cerebral ischemia. Present findings indicate that the degree of reduced CB immunoreactivity might be related with various neuronal damage/death overtime and corresponding areas after ischemic insults.</P>

Accelerated cerebral ischemic injury by activated macrophages/microglia after lipopolysaccharide microinjection into rat corpus callosum

Lee, Jae-Chul,Cho, Geum-Sil,Kim, Hye Jin,Lim, Ji-Hye,Oh, Yu-Kyoung,Nam, Wonwoo,Chung, Jang-Hyun,Kim, Won-Ki Wiley Subscription Services, Inc., A Wiley Company 2005 GLIA Vol.50 No.2

<P>In cerebral ischemic insults, activated inflammatory cells such as microglia and macrophages may be implicated in the pattern and degree of ischemic injury by producing various bioactive mediators. In the present study, we provide the evidence that activated microglia/macrophages accelerate cerebral ischemic injury by overexpression of inducible nitric oxide synthase (iNOS). To activate microglia/macrophages, a potent inflammation inducer lipopolysaccharide (LPS, 5 μg/5 μl) was microinjected into rat corpus callosum. Isolectin B4-positive microglia/macrophages were abundantly observed in ipsilateral hemisphere at 1 day after LPS injection. RT-PCR showed that LPS injection induced iNOS mRNA expression mostly in microglia/macrophages, peaking in intensity at 15 h after LPS injection. While ischemic injury was little evoked in control rats by 2-h middle cerebral artery occlusion (MCAO) followed by 3-h reperfusion, it was markedly increased in rats pre-injected with LPS 1 day before MCAO. However, no significant difference between control and LPS-pretreated groups was observed after 24-h reperfusion. The increased ischemic injury in LPS-treated rats was well correlated with iNOS level expressed over 3 orders of magnitude than in LPS-untreated rats. Immunohistochemical studies showed that iNOS- and nitrotyrosine (a peroxynitrite marker)-positive cells were prominent throughout the infarct area. NOS inhibitors aminoguanidine or N<SUP>G</SUP>-nitro-L-arginine, simultaneously injected with LPS, reduced the iNOS immunoreactivity and infarct volume, especially in penumbra regions. Total glutathione levels in ischemic regions were decreased more in LPS pre-injected rats than in control ones. Further defining the role of NO in cerebral ischemic insults would provide the rationale for new therapeutic strategies based on modulation of microglial and macrophageal NO production in the brain. © 2005 Wiley-Liss, Inc.</P>

Aging Exacerbates Intracerebral Hemorrhage-Induced Brain Injury

Lee, Jae-Chul,Cho, Geum-Sil,Choi, Byung-Ok,Kim, Hyoung Chun,Kim, Won-Ki Mary Ann Liebert 2009 JOURNAL OF NEUROTRAUMA - Vol.26 No.9

<P>Aging may be an important factor affecting brain injury by intracerebral hemorrhage (ICH). In the present study, we investigated the responses of glial cells and monocytes to intracerebral hemorrhage in normal and aged rats. ICH was induced by microinjecting autologous whole blood (15 microL) into the striatum of young (4 month old) and aged (24 month old) Sprague-Dawley rats. Age-dependent relations of brain tissue damage with glial and macrophageal responses were evaluated. Three days after ICH, activated microglia/macrophages with OX42-positive processes and swollen cytoplasm were more abundantly distributed around and inside the hemorrhagic lesions. These were more dramatic in aged versus the young rats. Western blot and immunohistochemistry analyses showed that the expression of interleukin-1beta protein after ICH was greater in aged rats, whereas the expression of GFAP and ciliary neurotrophic factor protein after ICH was significantly lower in aged rats. These results suggest that ICH causes more severe brain injury in aged rats most likely due to overactivation of microglia/macrophages and concomitant repression of reactive astrocytes.</P>

p63 Expression in the Gerbil Hippocampus Following Transient Ischemia and Effect of Ischemic Preconditioning on p63 Expression in the Ischemic Hippocampus.

Lee, Jae-Chul,Cho, Geum-Sil,Kim, In Hye,Park, Joon Ha,Cho, Jeong-Hwi,Ahn, Ji Hyeon,Bae, Eun Joo,Ahn, Ji Yun,Park, Chan Woo,Cho, Jun Hwi,Kim, Young-Myeong,Won, Moo-Ho,Lee, Hui Young Kluwer Academic/Plenum Publishers 2015 Neurochem Res Vol.40 No.5

<P>p63 is a transcription factor of p53 gene family, which are involved in development, differentiation and cell response to stress; however, its roles in ischemic preconditioning (IPC) in the brain are not clear. In the present study, we investigated the effect of IPC on p63 immunoreactivity caused by 5 min of transient cerebral ischemia in gerbils. IPC was induced by subjecting the gerbils to 2 min of transie ischemia 1 day prior to 5 min of transient ischemia. The animals were randomly assigned to four groups (sham-operated-group, ischemia-operated-group, IPC plus (+)-sham-operated-group and IPC + ischemia-operated-group). The number of viable neurons in the stratum pyramidale of the hippocampal CA1 region (CA1) was significantly increased by IPC + ischemia-operated-group compared with that in the ischemia-operated-group 5 days after ischemic insult. We found that strong p63 immunoreactivity was detected in the CA1 pyramidal neurons in the sham-operated-group, and the immunoreactivity was decreased with time after ischemia-reperfusion. In addition, strong p63 immunoreactivity was newly expressed in microglial cells of the CA1 region from 2 days after ischemia-reperfusion. In all the IPC + sham-operated-groups, p63 immunoreactivity in the CA1 pyramidal neurons was similar to that in the sham-operated-group, and the immunoreactivity was well maintained in the IPC + ischemia-operated-groups after cerebral ischemia. In brief, our present findings show that IPC dramatically protected the reduction of p63 immunoreactivity in the pyramidal neurons of the CA1 region after ischemia-reperfusion, and this result suggests that the expression of p63 may be necessary for neurons to survive after transient cerebral ischemia.</P>

Ischemic preconditioning protects neurons from damage and maintains the immunoreactivity of kynurenic acid in the gerbil hippocampal CA1 region following transient cerebral ischemia

LEE, JAE-CHUL,TAE, HYUN-JIN,CHO, GEUM-SIL,KIM, IN HYE,AHN, JI HYEON,PARK, JOON HA,CHEN, BAI HUI,CHO, JEONG-HWI,SHIN, BICH NA,CHO, JUN HWI,BAE, EUN JOO,PARK, JINSEU,KIM, YOUNG-MYEONG,CHOI, SOO YOUNG,WO D.A. Spandidos 2015 INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE Vol.35 No.6

<P>Pyramidal neurons in region I of hippocampus proper (CA1) are particularly vulnerable to excitotoxic processes following transient forebrain ischemia. Kynurenic acid (KYNA) is a small molecule derived from tryptophan when this amino acid is metabolized through the kynurenine pathway. In the present study, we examined the effects of ischemic preconditioning (IPC) on the immunoreactivity and protein levels of KYNA following 5 min of transient forebrain ischemia in gerbils. The animals were randomly assigned to 4 groups (sham-operated group, ischemia-operated group, IPC + sham-operated group and IPC + ischemia-operated group). IPC was induced by subjecting the gerbils to 2 min of ischemia followed by 1 day of recovery. In the ischemia-operated group, we observed a significant loss of pyramidal neurons in the CA1 stratum pyramidale (SP) at 5 days post-ischemia; however, in the IPC + ischemia-operated group, the pyramidal neurons were well protected. KYNA immunoreactivity in the SP of the ischemia-operated group was significantly altered following ischemia-reperfusion and was very low 5 days following ischemia-reperfusion. In the IPC + ischemia-operated group, however, KYNA immunoreactivity was constitutively detected in the SP of the CA1 region after the ischemic insult. We also found that the alteration pattern of the KYNA protein level in the CA1 region following ischemia was generally similar to the immunohistochemical changes observed. In brief, our findings demonstrated that IPC maintained and even increased KYNA immunoreactivity in the SP of the CA1 region following ischemia-reperfusion. The data from the present study thus indicate that the enhancement of KYNA expression by IPC may be necessary for neuronal survival following transient ischemic injury.</P>

Changes in the expression of DNA-binding/differentiation protein inhibitors in neurons and glial cells of the gerbil hippocampus following transient global cerebral ischemia

LEE, JAE-CHUL,CHEN, BAI HUI,CHO, JEONG-HWI,KIM, IN HYE,AHN, JI HYEON,PARK, JOON HA,TAE, HYUN-JIN,CHO, GEUM-SIL,YAN, BING CHUN,KIM, DAE WON,HWANG, IN KOO,PARK, JINSEU,LEE, YUN LYUL,CHOI, SOO YOUNG,WON, SPANDIDOS PUBLICATIONS 2015 MOLECULAR MEDICINE REPORTS Vol.11 No.4

<P>Inhibitors of DNA-binding/differentiation (ID) proteins bind to basic helix-loop-helix (bHLH) transcription factors, including those that regulate differentiation and cell-cycle progression during development, and regulate gene transcription. However, little is known about the role of ID proteins in the brain under transient cerebral ischemic conditions. In the present study, we examined the effects of ischemia-reperfusion (I-R) injury on the immunoreactivity and protein levels of IDs 1–4 in the gerbil hippocampus proper <I>Cornu Ammonis</I> regions CA1–3 following 5 min of transient cerebral ischemia. Strong ID1 immunoreactivity was detected in the nuclei of pyramidal neurons in the hippocampal CA1–3 regions; immunoreactivity was significantly changed following I-R in the CA1 region, but not in the CA2/3 region. Five days following I-R, ID1 immunoreactivity was not detected in the CA1 pyramidal neurons. ID1 immunoreactivity was detected only in GABAergic interneurons in the ischemic CA1 region. Weak ID4 immunoreactivity was detected in non-pyramidal cells, and immunoreactivity was again only changed in the ischemic CA1 region. Five days following I-R, strong ID4 immunoreactivity was detected in non-pyramidal cells, which were identified as microglia, and not astrocytes, in the ischemic CA1 region. Furthermore, changes in the protein levels of ID1 and ID4 in the ischemic CA1 region studied by western blot were consistent with patterns of immunoreactivity. In summary, these results indicate that immunoreactivity and protein levels of ID1 and ID4 are distinctively altered following transient cerebral ischemia only in the CA1 region, and that the changes in ID1 and ID4 expression may relate to the ischemia-induced delayed neuronal death.</P>

Effects of transient cerebral ischemia on the expression of DNA methyltransferase 1 in the gerbil hippocampal CA1 region.

Lee, Jae-Chul,Park, Joon Ha,Yan, Bing Chun,Kim, In Hye,Cho, Geum-Sil,Jeoung, Dooil,Kwon, Young-Geun,Kim, Young-Myeong,Lee, Yun Lyul,Shin, Hyung-Cheul,Won, Moo-Ho Kluwer Academic/Plenum Publishers 2013 Neurochem Res Vol.38 No.1

<P>DNA methylation is a key epigenetic modification of DNA that is catalyzed by DNA methyltransferases (Dnmt). Increasing evidences suggest that DNA methylation in neurons regulates synaptic plasticity as well as neuronal network activity. In the present study, we investigated the changes in DNA methyltransferases 1 (Dnmt1) immunoreactivity and its protein levels in the gerbil hippocampal CA1 region after 5 min of transient global cerebral ischemia. CA1 pyramidal neurons were well stained with NeuN (a neuron-specific soluble nuclear antigen) antibody in the sham-group, Four days after ischemia-reperfusion (I-R), NeuN-positive ((+)) cells were significantly decreased in the stratum pyramidale (SP) of the CA1 region, and many Fluro-Jade B (a marker for neuronal degeneration)(+) cells were observed in the SP. Dnmt1 immunoreactivity was well detected in all the layers of the sham-group. Dnmt1 immunoreactivity was hardly detected only in the stratum pyramidale of the CA1 region from 4 days post-ischemia; however, at these times, Dnmt1 immunoreactivity was newly expressed in GABAergic interneurons or astrocytes in the ischemic CA1 region. In addition, the level of Dnmt1 was lowest at 4 days post-ischemia. In brief, both the Dnmt1 immunoreactivity and protein levels were distinctively decreased in the ischemic CA1 region 4 days after transient cerebral ischemia. These results indicate that the decrease of Dnmt1 expression at 4 days post-ischemia may be related to ischemia-induced delayed neuronal death.</P>

Roles of HIF-1α, VEGF, and NF-κB in Ischemic Preconditioning-Mediated Neuroprotection of Hippocampal CA1 Pyramidal Neurons Against a Subsequent Transient Cerebral Ischemia

Lee, Jae-Chul,Tae, Hyun-Jin,Kim, In Hye,Cho, Jeong Hwi,Lee, Tae-Kyeong,Park, Joon Ha,Ahn, Ji Hyeon,Choi, Soo Young,Bai, Hui Chen,Shin, Bich-Na,Cho, Geum-Sil,Kim, Dae Won,Kang, Il Jun,Kwon, Young-Guen Humana Press 2017 Molecular Neurobiology Vol. No.

<P>Ischemic preconditioning (IPC) provides neuroprotection against subsequent severe ischemic insults by specific mechanisms. We tested the hypothesis that IPC attenuates post-ischemic neuronal death in the gerbil hippocampal CA1 region (CA1) throughout hypoxia inducible factor-1 alpha (HIF-1 alpha) and its associated factors such as vascular endothelial growth factor (VEGF) and nuclear factor-kappa B (NF-kappa B). Lethal ischemia (LI) without IPC increased expressions of HIF-1 alpha, VEGF, and p-I kappa B-alpha (/and translocation of NF-kappa B p65 into nucleus) in CA1 pyramidal neurons at 12 h and/or 1-day post-LI; thereafter, their expressions were decreased in the CA1 pyramidal neurons with time and newly expressed in non-pyramidal cells (pericytes), and the CA1 pyramidal neurons were dead at 5-day post-LI, and, at this point in time, their immunoreactivities were newly expressed in pericytes. In animals with IPC subjected to LI (IPC/LI)-group), CA1 pyramidal neurons were well protected, and expressions of HIF-1 alpha, VEGF, and p-I kappa B-alpha (/and translocation of NF-kappa B p65 into nucleus) were significantly increased compared to the sham-group and maintained after LI. Whereas, treatment with 2ME2 (a HIF-1 alpha inhibitor) into the IPC/LI-group did not preserve the IPC-mediated increases of HIF-1 alpha, VEGF, and p-I kappa B-alpha (/and translocation of NF-kappa B p65 into nucleus) expressions and did not show IPC-mediated neuroprotection. In brief, IPC protected CA1 pyramidal neurons from LI by upregulation of HIF-1 alpha, VEGF, and p-I kappa B-alpha expressions. This study suggests that IPC increases HIF-1 alpha expression in CA1 pyramidal neurons, which enhances VEGF expression and NF-kappa B activation and that IPC may be a strategy for a therapeutic intervention of cerebral ischemic injury.</P>