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1.
International Neurourology Journal ; : S8-18, 2021.
Article in English | WPRIM | ID: wpr-898792

ABSTRACT

Epileptic encephalopathy (EE) is a devastating pediatric disease that features medically resistant seizures, which can contribute to global developmental delays. Despite technological advancements in genetics, the neurobiological mechanisms of EEs are not fully understood, leaving few therapeutic options for affected patients. In this review, we introduce the most common EEs in pediatrics (i.e., Ohtahara syndrome, Dravet syndrome, and Lennox-Gastaut syndrome) and their molecular mechanisms that cause excitation/inhibition imbalances. We then discuss some of the essential molecules that are frequently dysregulated in EEs. Specifically, we explore voltage-gated ion channels, synaptic transmission-related proteins, and ligand-gated ion channels in association with the pathophysiology of Ohtahara syndrome, Dravet syndrome, and Lennox-Gastaut syndrome. Finally, we review currently available antiepileptic drugs used to treat seizures in patients with EEs. Since these patients often fail to achieve seizure relief even with the combination therapy, further extensive research efforts to explore the involved molecular mechanisms will be required to develop new drugs for patients with intractable epilepsy.

2.
International Neurourology Journal ; : S8-18, 2021.
Article in English | WPRIM | ID: wpr-891088

ABSTRACT

Epileptic encephalopathy (EE) is a devastating pediatric disease that features medically resistant seizures, which can contribute to global developmental delays. Despite technological advancements in genetics, the neurobiological mechanisms of EEs are not fully understood, leaving few therapeutic options for affected patients. In this review, we introduce the most common EEs in pediatrics (i.e., Ohtahara syndrome, Dravet syndrome, and Lennox-Gastaut syndrome) and their molecular mechanisms that cause excitation/inhibition imbalances. We then discuss some of the essential molecules that are frequently dysregulated in EEs. Specifically, we explore voltage-gated ion channels, synaptic transmission-related proteins, and ligand-gated ion channels in association with the pathophysiology of Ohtahara syndrome, Dravet syndrome, and Lennox-Gastaut syndrome. Finally, we review currently available antiepileptic drugs used to treat seizures in patients with EEs. Since these patients often fail to achieve seizure relief even with the combination therapy, further extensive research efforts to explore the involved molecular mechanisms will be required to develop new drugs for patients with intractable epilepsy.

3.
The Korean Journal of Physiology and Pharmacology ; : 81-88, 2020.
Article in English | WPRIM | ID: wpr-787136

ABSTRACT

Regulator of calcineurin 1 (RCAN1) can be induced by an intracellular calcium increase and oxidative stress, which are characteristic features of temporal lobe epilepsy. Thus, we investigated the spatiotemporal expression and cellular localization of RCAN1 protein and mRNA in the mouse hippocampus after pilocarpine-induced status epilepticus (SE). Male C57BL/6 mice were given pilocarpine hydrochloride (280 mg/kg, i.p.) and allowed to develop 2 h of SE. Then the animals were given diazepam (10 mg/kg, i.p.) to stop the seizures and sacrificed at 1, 3, 7, 14, or 28 day after SE. Cresyl violet staining showed that pilocarpine-induced SE resulted in cell death in the CA1 and CA3 subfields of the hippocampus from 3 day after SE. RCAN1 immunoreactivity showed that RCAN1 was mainly expressed in neurons in the shammanipulated hippocampi. At 1 day after SE, RCAN1 expression became detected in hippocampal neuropils. However, RCAN1 signals were markedly enhanced in cells with stellate morphology at 3 and 7 day after SE, which were confirmed to be reactive astrocytes, but not microglia by double immunofluorescence. In addition, real-time reverse transcriptase–polymerase chain reaction showed a significant upregulation of RCAN1 isoform 4 (RCAN1-4) mRNA in the SE-induced hippocampi. Finally, in situ hybridization with immunohistochemistry revealed astrocytic expression of RCAN1-4 after SE. These results demonstrate astrocytic upregulation of RCAN1 and RCAN1-4 in the mouse hippocampus in the acute and subacute phases of epileptogenesis, providing foundational information for the potential role of RCAN1 in reactive astrocytes during epileptogenesis.


Subject(s)
Animals , Humans , Male , Mice , Astrocytes , Calcineurin , Calcium , Cell Death , Diazepam , Epilepsy , Epilepsy, Temporal Lobe , Fluorescent Antibody Technique , Hippocampus , Immunohistochemistry , In Situ Hybridization , Microglia , Neurons , Neuropil , Oxidative Stress , Pilocarpine , RNA, Messenger , Seizures , Status Epilepticus , Up-Regulation , Viola
4.
The Korean Journal of Physiology and Pharmacology ; : 89-99, 2020.
Article in English | WPRIM | ID: wpr-787135

ABSTRACT

Although microscopic analysis of tissue slides has been the basis for disease diagnosis for decades, intra- and inter-observer variabilities remain issues to be resolved. The recent introduction of digital scanners has allowed for using deep learning in the analysis of tissue images because many whole slide images (WSIs) are accessible to researchers. In the present study, we investigated the possibility of a deep learning-based, fully automated, computer-aided diagnosis system with WSIs from a stomach adenocarcinoma dataset. Three different convolutional neural network architectures were tested to determine the better architecture for tissue classifier. Each network was trained to classify small tissue patches into normal or tumor. Based on the patch-level classification, tumor probability heatmaps can be overlaid on tissue images. We observed three different tissue patterns, including clear normal, clear tumor and ambiguous cases. We suggest that longer inspection time can be assigned to ambiguous cases compared to clear normal cases, increasing the accuracy and efficiency of histopathologic diagnosis by pre-evaluating the status of the WSIs. When the classifier was tested with completely different WSI dataset, the performance was not optimal because of the different tissue preparation quality. By including a small amount of data from the new dataset for training, the performance for the new dataset was much enhanced. These results indicated that WSI dataset should include tissues prepared from many different preparation conditions to construct a generalized tissue classifier. Thus, multi-national/multi-center dataset should be built for the application of deep learning in the real world medical practice.


Subject(s)
Adenocarcinoma , Classification , Dataset , Diagnosis , Learning , Observer Variation , Stomach
5.
The Korean Journal of Physiology and Pharmacology ; : 281-289, 2019.
Article in English | WPRIM | ID: wpr-761788

ABSTRACT

Vascular endothelial growth factor (VEGF)-C and its receptor, vascular endothelial growth factor receptor (VEGFR)-3, are responsible for lymphangiogenesis in both embryos and adults. In epilepsy, the expression of VEGF-C and VEGFR-3 was significantly upregulated in the human brains affected with temporal lobe epilepsy. Moreover, pharmacologic inhibition of VEGF receptors after acute seizures could suppress the generation of spontaneous recurrent seizures, suggesting a critical role of VEGF-related signaling in epilepsy. Therefore, in the present study, the spatiotemporal expression of VEGF-C and VEGFR-3 against pilocarpine-induced status epilepticus (SE) was investigated in C57BL/6N mice using immunohistochemistry. At 1 day after SE, hippocampal astrocytes and microglia were activated. Pyramidal neuronal death was observed at 4 days after SE. In the subpyramidal zone, VEGF-C expression gradually increased and peaked at 7 days after SE, while VEGFR-3 was significantly upregulated at 4 days after SE and began to decrease at 7 days after SE. Most VEGF-C/VEGFR-3-expressing cells were pyramidal neurons, but VEGF-C was also observed in some astrocytes in sham-manipulated animals. However, at 4 days and 7 days after SE, both VEGFR-3 and VEGF-C immunoreactivities were observed mainly in astrocytes and in some microglia of the stratum radiatum and lacunosum-moleculare of the hippocampus, respectively. These data indicate that VEGF-C and VEGFR-3 can be upregulated in hippocampal astrocytes and microglia after pilocarpine-induced SE, providing basic information about VEGF-C and VEGFR-3 expression patterns following acute seizures.


Subject(s)
Adult , Animals , Humans , Mice , Astrocytes , Brain , Embryonic Structures , Epilepsy , Epilepsy, Temporal Lobe , Hippocampus , Immunohistochemistry , Lymphangiogenesis , Microglia , Pyramidal Cells , Receptors, Vascular Endothelial Growth Factor , Seizures , Status Epilepticus , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factor C , Vascular Endothelial Growth Factor Receptor-3
6.
The Korean Journal of Physiology and Pharmacology ; : 131-139, 2019.
Article in English | WPRIM | ID: wpr-728015

ABSTRACT

Manually reviewing electroencephalograms (EEGs) is labor-intensive and demands automated seizure detection systems. To construct an efficient and robust event detector for experimental seizures from continuous EEG monitoring, we combined spectral analysis and deep neural networks. A deep neural network was trained to discriminate periodograms of 5-sec EEG segments from annotated convulsive seizures and the pre- and post-EEG segments. To use the entire EEG for training, a second network was trained with non-seizure EEGs that were misclassified as seizures by the first network. By sequentially applying the dual deep neural networks and simple pre- and post-processing, our autodetector identified all seizure events in 4,272 h of test EEG traces, with only 6 false positive events, corresponding to 100% sensitivity and 98% positive predictive value. Moreover, with pre-processing to reduce the computational burden, scanning and classifying 8,977 h of training and test EEG datasets took only 2.28 h with a personal computer. These results demonstrate that combining a basic feature extractor with dual deep neural networks and rule-based pre- and post-processing can detect convulsive seizures with great accuracy and low computational burden, highlighting the feasibility of our automated seizure detection algorithm.


Subject(s)
Animals , Mice , Dataset , Electroencephalography , Epilepsy , Microcomputers , Seizures
7.
International Neurourology Journal ; : S131-S138, 2018.
Article in English | WPRIM | ID: wpr-717678

ABSTRACT

PURPOSE: Mesenchymal stem cells (MSCs) have demonstrated great promises for the treatment of ischemic stroke. Previously, we identified a new source of MSCs located in the inferior turbinate. We investigated therapeutic potentials of human turbinate- derived mesenchymal stem cells (hTMSCs) in ischemic stroke. METHODS: Ischemic stroke was induced by the intraluminal occlusion of middle cerebral artery (MCAo) for 50 minutes in rats. At one day after MCAo, hTMSCs, adipose tissue-derived MSCs (AdMSCs), or phosphate buffered saline (PBS) were transplanted into the striatum. Functional recovery was assessed by repeating behavioral tests including modified neurologic severity score and corner test. At 14 days after MCAo, brains were stained with hematoxylin and eosin (H&E) for measuring infarct volume. The survival of grafted MSCs was evaluated by immunohistochemistry to human nuclei (hNU). Immunohistochemistry with anti-doublecortin (anti-DCX) was performed to assess hippocampal neurogenesis. RESULTS: Transplantation of hTMSCs following MCAo showed improvements of neurologic function, which was comparable with that of AdMSCs. H&E staining showed no difference in infarct volume among 3 groups. Regarding the survival of grafted MSCs, the number of hNU-expressing cells was not different between hTMSCs- and AdMSCs-treated groups. Finally, hTMSCs increased the number of subgranular DCX-positive cells compared to PBS-treated controls, without affecting hilar ectopic migration of newborn neurons. CONCLUSIONS: hTMSCs could improve functional recovery following ischemic stroke, of which efficacy was similar to AdMSCs. Although hTMSCs showed comparable infarct size and survival of grafted MSCs, transplantation of hTMSCs could upregulate subgranular neurogenesis with no impact on ectopically migrating newborn neurons.


Subject(s)
Animals , Humans , Infant, Newborn , Rats , Behavior Rating Scale , Brain , Eosine Yellowish-(YS) , Hematoxylin , Immunohistochemistry , Mesenchymal Stem Cells , Middle Cerebral Artery , Neurogenesis , Neurons , Stroke , Transplantation , Transplants , Turbinates
8.
International Neurourology Journal ; : 2-8, 2018.
Article in English | WPRIM | ID: wpr-713690

ABSTRACT

Micturition is a complex process involving the bladder, spinal cord, and the brain. Highly sophisticated central neural program controls bladder function by utilizing multiple brain regions, including pons and suprapontine structures. Periaqueductal grey, insula, anterior cingulate cortex, and medial prefrontal cortex are components of suprapontine micturition centers. Under pathologic conditions such as epilepsy, urinary dysfunction is a frequent symptom and it seems to be associated with increased suprapontine cortical activity. Interestingly, micturition can also trigger seizures known as reflex epilepsy. During voiding behavior, frontotemporal cortical activation has been reported and it may induce reflex seizures. As current researches are only limited to present clinical cases, more rigorous investigations are needed to elucidate biological mechanisms of micturition to advance our knowledge on the process of micturition in physiology and pathology.


Subject(s)
Brain , Epilepsy , Epilepsy, Reflex , Gyrus Cinguli , Pathology , Physiology , Pons , Prefrontal Cortex , Reflex , Seizures , Spinal Cord , Urinary Bladder , Urination
9.
The Korean Journal of Physiology and Pharmacology ; : 643-650, 2017.
Article in English | WPRIM | ID: wpr-727950

ABSTRACT

Vascular dementia (VaD) is a group of heterogeneous diseases with the common feature of cerebral hypoperfusion. To identify key factors contributing to VaD pathophysiology, we performed a detailed comparison of Wistar and Sprague–Dawley (SD) rats subjected to permanent bilateral common carotid artery occlusion (BCCAo). Eight-week old male Wistar and SD rats underwent BCCAo, followed by a reference memory test using a five-radial arm maze with tactile cues. Continuous monitoring of cerebral blood flow (CBF) was performed with a laser Doppler perfusion imaging (LDPI) system. A separate cohort of animals was sacrificed for evaluation of the brain vasculature and white matter damage after BCCAo. We found reference memory impairment in Wistar rats, but not in SD rats. Moreover, our LDPI system revealed that Wistar rats had significant hypoperfusion in the brain region supplied by the posterior cerebral artery (PCA). Furthermore, Wistar rats showed more profound CBF reduction in the forebrain region than did SD rats. Post-mortem analysis of brain vasculature demonstrated greater PCA plasticity at all time points after BCCAo in Wistar rats. Finally, we confirmed white matter rarefaction that was only observed in Wistar rats. Our studies show a comprehensive and dynamic CBF status after BCCAo in Wistar rats in addition to severe PCA dolichoectasia, which correlated well with white matter lesion and memory decline.


Subject(s)
Animals , Humans , Male , Rats , Arm , Brain , Carotid Artery, Common , Cerebrovascular Circulation , Cohort Studies , Cues , Dementia, Vascular , Memory , Passive Cutaneous Anaphylaxis , Perfusion Imaging , Plastics , Posterior Cerebral Artery , Prosencephalon , Rats, Wistar , White Matter
10.
The Korean Journal of Physiology and Pharmacology ; : 185-192, 2016.
Article in English | WPRIM | ID: wpr-728536

ABSTRACT

Ampicillin, a beta-lactam antibiotic, dose-dependently protects neurons against ischemic brain injury. The present study was performed to investigate the neuroprotective mechanism of ampicillin in a mouse model of transient global forebrain ischemia. Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral common carotid artery occlusion for 40 min. Before transient forebrain ischemia, ampicillin (200 mg/kg, intraperitoneally [i.p.]) or penicillin G (6,000 U/kg or 20,000 U/kg, i.p.) was administered daily for 5 days. The pretreatment with ampicillin but not with penicillin G signifi cantly attenuated neuronal damage in the hippocampal CA1 subfield. Mechanistically, the increased activity of matrix metalloproteinases (MMPs) following forebrain ischemia was also attenuated by ampicillin treatment. In addition, the ampicillin treatment reversed increased immunoreactivities to glial fibrillary acidic protein and isolectin B4, markers of astrocytes and microglia, respectively. Furthermore, the ampicillin treatment significantly increased the level of glutamate transporter-1, and dihydrokainic acid (DHK, 10 mg/kg, i.p.), an inhibitor of glutamate transporter-1 (GLT-1), reversed the neuroprotective effect of ampicillin. Taken together, these data indicate that ampicillin provides neuroprotection against ischemia-reperfusion brain injury, possibly through inducing the GLT-1 protein and inhibiting the activity of MMP in the mouse hippocampus.


Subject(s)
Animals , Humans , Male , Mice , Ampicillin , Astrocytes , Brain Injuries , Carotid Artery, Common , Glial Fibrillary Acidic Protein , Glutamic Acid , Halothane , Hippocampus , Ischemia , Lectins , Matrix Metalloproteinases , Microglia , Neurons , Neuroprotective Agents , Penicillin G , Prosencephalon
11.
The Korean Journal of Physiology and Pharmacology ; : 353-361, 2011.
Article in English | WPRIM | ID: wpr-728319

ABSTRACT

In this study, cyanidin-3-glucoside (C3G) fraction extracted from the mulberry fruit (Morus alba L.) was investigated for its neuroprotective effects against oxygen-glucose deprivation (OGD) and glutamate-induced cell death in rat primary cortical neurons. Cell membrane damage and mitochondrial function were assessed by LDH release and MTT reduction assays, respectively. A time-course study of OGD-induced cell death of primary cortical neurons at 7 days in vitro (DIV) indicated that neuronal death was OGD duration-dependent. It was also demonstrated that OGD for 3.5 h resulted in approximately 50% cell death, as determined by the LDH release assay. Treatments with mulberry C3G fraction prevented membrane damage and preserved the mitochondrial function of the primary cortical neurons exposed to OGD for 3.5 h in a concentration-dependent manner. Glutamate-induced cell death was more pronounced in DIV-9 and DIV-11 cells than that in DIV-7 neurons, and an application of 50microM glutamate was shown to induce approximately 40% cell death in DIV-9 neurons. Interestingly, treatment with mulberry C3G fraction did not provide a protective effect against glutamate-induced cell death in primary cortical neurons. On the other hand, treatment with mulberry C3G fraction maintained the mitochondrial membrane potential (MMP) in primary cortical neurons exposed to OGD as assessed by the intensity of rhodamine-123 fluorescence. These results therefore suggest that the neuroprotective effects of mulberry C3G fraction are mediated by the maintenance of the MMP and mitochondrial function but not by attenuating glutamate-induced excitotoxicity in rat primary cortical neurons.


Subject(s)
Animals , Rats , Anthocyanins , Cell Death , Cell Membrane , Fluorescence , Fruit , Glucosides , Glutamic Acid , Hand , Membrane Potential, Mitochondrial , Membranes , Morus , Neurons , Neuroprotective Agents
12.
The Korean Journal of Physiology and Pharmacology ; : 149-156, 2011.
Article in English | WPRIM | ID: wpr-727888

ABSTRACT

Golgi SNAP receptor complex 1 (GS28) has been implicated in vesicular transport between intra-Golgi networks and between endoplasmic reticulum (ER) and Golgi. Additional role(s) of GS28 within cells have not been well characterized. We observed decreased expression of GS28 in rat ischemic hippocampus. In this study, we examined the role of GS28 and its molecular mechanisms in neuronal (SK-N-SH) cell death induced by hydrogen peroxide (H2O2). GS28 siRNA-transfected cells treated with H2O2 showed a significant increase in cytotoxicity under glutathione (GSH)-depleted conditions after pretreatment with buthionine sulfoximine, which corresponded to an increase of intracellular reactive oxygen species (ROS) in the cells. Pretreatment of GS28 siRNA-transfected cells with p38 chemical inhibitor significantly inhibited cytotoxicity; we also observed that p38 was activated in the cells by immunoblot analysis. We confirmed the role of p38 MAPK in cotransfected cells with GS28 siRNA and p38 siRNA in the cell viability assay, flow cytometry, and immunoblot. Involvement of apoptotic or autophagic processes in the cells was not shown in the cell viability, flow cytometry, and immunoblot analyses. However, pretreatment of the cells with necrostatin-1 completely inhibited H2O2-induced cytotoxicity, ROS generation, and p38 activation, indicating that the cell death is necroptotic. Collectively these data imply that H2O2 induces necroptotic cell death in the GS28 siRNA-transfected cells and that the necroptotic signals are mediated by sequential activations in RIP1/p38/ROS. Taken together, these results indicate that GS28 has a protective role in H2O2-induced necroptosis via inhibition of p38 MAPK in GSH-depleted neuronal cells.


Subject(s)
Animals , Rats , Buthionine Sulfoximine , Cell Death , Cell Survival , Endoplasmic Reticulum , Flow Cytometry , Glutathione , Hippocampus , Hydrogen , Hydrogen Peroxide , Imidazoles , Indoles , Methionine , Neurons , p38 Mitogen-Activated Protein Kinases , Reactive Oxygen Species , RNA, Small Interfering , SNARE Proteins
13.
The Korean Journal of Physiology and Pharmacology ; : 287-291, 2008.
Article in English | WPRIM | ID: wpr-728374

ABSTRACT

Ampicillin, a beta-lactam antibiotic, has been reported to induce astrocytic glutamate transporter-1 which plays a crucial role in protecting neurons against glutamate excitotoxicity. We investigated the effect of ampicillin on neuronal damage in the mouse hippocampus and neostriatum following transient global forebrain ischemia. Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral occlusion of the common carotid artery for 40 min. Ampicillin was administered post-ischemically (for 3 days) and/or pre-ischemically (for 3~5 days until one day before the onset of ischemia). Pre- and post-ischemic treatment with ampicillin (50 mg/kg/day or 200 mg/kg/day) prevented ischemic neuronal death in the medial CA1 area of the hippocampus as well as the neostriatum in a dose-dependent manner. In addition, ischemic neuronal damage was reduced by pre-ischemic treatment with ampicillin (200 mg/kg/day). In summary, our results suggest that ampicillin plays a functional role as a chemical preconditioning agent that protects hippocampal neurons from ischemic insult.


Subject(s)
Animals , Humans , Male , Mice , Ampicillin , Carotid Artery, Common , Glutamic Acid , Halothane , Hippocampus , Ischemia , Neostriatum , Neurons , Prosencephalon
14.
The Korean Journal of Physiology and Pharmacology ; : 89-94, 2008.
Article in English | WPRIM | ID: wpr-728602

ABSTRACT

In order to reproduce chronic cerebral hypoperfusion as it occurs in human aging and Alzheimer's disease, we introduced permanent, bilateral occlusion of the common carotid arteries (BCCAO) in rats (Farkas et al, 2007). Here, we induced BCCAO in two different rat strains in order to determine whether there was a strain difference in the pathogenic response to BCCAO. Male Wistar and Sprague-Dawley (SD) rats (250-270 g) were subjected to BCCAO for three weeks. Kluver-Barrera and cresyl violet staining were used to evaluate white matter and gray matter damage, respectively. Wistar rats had a considerably higher mortality rate (four of 14 rats) as compared to SD rats (one of 15 rats) following BCCAO. Complete loss of pupillary light reflex occurred in all Wistar rats that survived, but loss of pupillary light reflex did not occur at all in SD rats. Moreover, BCCAO induced marked vacuolation in the optic tract of Wistar rats as compared to SD rats. In contrast, SD rats showed fewer CA1 hippocampal neurons than Wistar rats following BCCAO. These results suggest that the neuropathological process induced by BCCAO takes place in a region-specific pattern that varies according to the strain of rat involved.


Subject(s)
Animals , Humans , Male , Rats , Aging , Alzheimer Disease , Benzoxazines , Carotid Artery, Common , Hypogonadism , Light , Mitochondrial Diseases , Neurons , Ophthalmoplegia , Rats, Wistar , Reflex , Sprains and Strains , Viola , Visual Pathways
15.
Experimental & Molecular Medicine ; : 556-563, 2007.
Article in English | WPRIM | ID: wpr-174047

ABSTRACT

Several studies have demonstrated that ischemic preconditioning increases superoxide dismutase activity, but it is unclear how ischemic preconditioning affects events downstream of hydrogen peroxide production during subsequent severe ischemia and reperfusion in the hippocampus. To answer this question, we investigated whether ischemic preconditioning in the hippocampal CA1 region increases the activities of antioxidant enzymes glutathione peroxidase and catalase, resulting in a decrease in the level of hydroxyl radicals during subsequent severe ischemia-reperfusion. Transient forebrain ischemia was induced by four-vessel occlusion in rats. Ischemic preconditioning for 3 min or a sham operation was performed and a 15-min severe ischemia was induced three days later. Ischemic preconditioning preserved the CA1 hippocampal neurons following severe ischemia. The concentration of 2,3-dihydroxybenzoic acid, an indicator of hydroxyl radical, was measured using in vivo microdialysis technique combined with HPLC. The ischemia-induced increase in the ratio of 2,3-dihydroxybenzoic acid concentration relative to baseline did not differ significantly between preconditioned and control groups. On the other hand, activities of the antioxidant enzymes glutathione peroxidase-1 and catalase were significantly increased at 3 days after ischemic preconditioning in the hippocampus. Our results suggest that, in preconditioned rats, while hydrogen peroxide is generated from severe ischemia, the activity of catalase and glutathione peroxidase-1 is correspondingly increased to eliminate the excessive hydrogen peroxide. However, our results show that the enhanced activity of these antioxidant enzymes in preconditioned rats is not sufficient to decrease hydroxyl radical levels during subsequent severe ischemia-reperfusion.


Subject(s)
Animals , Male , Rats , Antioxidants/metabolism , Catalase/metabolism , Enzyme Activation , Glutathione Peroxidase/metabolism , Hippocampus/blood supply , Hydrogen Peroxide/metabolism , Hydroxybenzoates/metabolism , Hydroxyl Radical/metabolism , Ischemic Attack, Transient/metabolism , Ischemic Preconditioning , Prosencephalon , Rats, Sprague-Dawley , Reperfusion Injury/metabolism
16.
The Korean Journal of Physiology and Pharmacology ; : 167-172, 2006.
Article in English | WPRIM | ID: wpr-728562

ABSTRACT

In the present study, we developed a simple method to predict the neuronal cell death in the mouse hippocampus and striatum following transient global forebrain ischemia by evaluating both cerebral blood flow and the plasticity of the posterior communicating artery (PcomA). Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral occlusion of the common carotid artery (BCCAO) for 30 min. The regional cerebral blood flow (rCBF) was measured by laser Doppler flowmetry. The plasticity of PcomA was visualized by intravascular perfusion of India ink solution. When animals had the residual cortical microperfusion less than 15% as well as the smaller PcomA whose diameter was less than one third compared with that of basilar artery, neuronal damage in the hippocampal subfields including CA1, CA2, and CA4, and in the striatum was consistently observed. Especially, when mice met these two criteria, marked neuronal damage was observed in CA2 subfield of the hippocampus. In contrast, after transient BCCAO, neuronal damage was consistently produced in the striatum, dependent more on the degree of rCBF reduction than on the plasticity of PcomA. The present study provided simple and highly reproducible criteria to induce the neuronal cell death in the vulnerable mice brain areas including the hippocampus and striatum after transient global forebrain ischemia.


Subject(s)
Animals , Humans , Male , Mice , Arteries , Basilar Artery , Brain , Carotid Artery, Common , Cell Death , Halothane , Hippocampus , India , Ink , Ischemia , Laser-Doppler Flowmetry , Neurons , Perfusion , Plastics , Prosencephalon
17.
The Korean Journal of Physiology and Pharmacology ; : 1-5, 2004.
Article in English | WPRIM | ID: wpr-728510

ABSTRACT

Transient forebrain ischemia results in the delayed neuronal death in the CA1 area of the hippocampus. The present study was performed to determine effects of aminoguanidine, a selective iNOS inhibitor, on the generation of peroxynitrite and delayed neuronal death occurring in the hippocampus following transient forebrain ischemia. Transient forebrain ischemia was produced in the conscious rats by four-vessel occlusion for 10 min. Treatment with aminoguanidine (100 mg/kg or 200 mg/kg, i.p.) or saline (0.4 ml/100 g, i.p.) was started 30 min following ischemia-reperfusion and the animals were then injected twice daily until 12 h before sacrifice. Immunohistochemical method was used to detect 3-nitrotyrosine, a marker of peroxynitrite production. Posttreatment of aminoguanidine (200 mg/kg) significantly attenuated the neuronal death in the hippocampal CA1 area 3 days, but not 7 days, after ischemia-reperfusion. 3-Nitrotyrosine immunoreactivity was enhanced in the hippocampal CA1 area 3 days after reperfusion, which was prevented by the treatment of aminoguanidine (100 mg/kg and 200 mg/kg). Our findings showed that (1) the generation of peroxynitrite in the hippocampal CA1 area 3 days after ischemia-reperfusion was dependent on the iNOS activity; (2) the postischemic delayed neuronal death was attenuated in the early phase through the prevention of peroxynitrite generation by an iNOS inhibitor.


Subject(s)
Animals , Rats , Hippocampus , Ischemia , Neurons , Peroxynitrous Acid , Prosencephalon , Reperfusion
18.
Korean Journal of Community Nutrition ; : 504-511, 2003.
Article in Korean | WPRIM | ID: wpr-118440

ABSTRACT

This study was performed to evaluate the effectiveness of a nutrition education program developed for nutritionally imbalanced adolescents. A summer nutrition camp was held for 23 overweight and 16 underweight subjects. Its effectiveness with regard to was evaluated at the end of the camp and 6 months later. Nutrition knowledge, nutritional attitude, food behavior, nutrient intake, exercise habit and ideal body figures desired by the subjects. The results showed significantly higher nutrition knowledge scores at the end of the camp as compared to those obtained prior to the camp program, and these scores were maintained for at least six months. Nutrition attitude scores also improved after the education program, and these improved scores also lasted for 6 months. However, the food behavior scores measured 6 months after the education program were not significantly different from those obtained prior to the camp. Also, the exorcist habit, the ideal body figures and the body figures desired by the subjects remained unchanged. When nutrient intakes of subjects were assessed before the program and 6 months later, the mean daily vitamin C intake was significantly increased after the education program. Also, the intake of iron from plant food sources increased in the overweight subjects, while less iron from animal source were consumed by the underweight subjects. Both groups tended to consume more vegetables and fruits 6 months after the education program which may have contribute to the higher vitamin C and plant-based iron intakes. These results indicate that a 4-day nutrition education camp program sustained changes in nutrition knowledge and nutrition attitude for 6 months. The increased intake of vegetables and fruits was also achieved through this education program. However, changes in dietary behavior in adolescents may require repeated education.


Subject(s)
Adolescent , Animals , Humans , Ascorbic Acid , Education , Fruit , Iron , Overweight , Plants , Thinness , Vegetables
19.
Korean Journal of Community Nutrition ; : 111-120, 2002.
Article in Korean | WPRIM | ID: wpr-168000

ABSTRACT

Postmenopausal women lose more bone mass than men as a result of estrogen deprivation. The resultant low bone mineral density (BMD) is a major risk factor in the development of osteoporosis. Calcium, phosphorus and magnesium are main components of bone. The purpose of this study is to investigate nutrient intake and serum osteocalcin, Ca, P and Mg and their correlation to bone mineral density in Korean postmenopausal women residing in rural areas. We conducted 24 hour dietary recalls, anthropometric measurements and blood analysis on 60 postmenopausal women. The BMD of the lumbar spine (L2-->L4) and the femoral neck were measured by dual energy X-ray absorptiometry (DEXA). Subjects were assigned to one of three groups:normal (T-score> -1, n=20), osteopenia (-2.5> T-score< or = -1, n=23), and osteoporosis ( T-score< or = -2.5, n=17). The mean age, height, weight and BMI were 62.37 yr, 154.36 cm, 55.28 kg and 23.18 kg/m2 respectively. The mean daily energy and protein intakes were 76.35% and 87.41% of RDA for Koreans. The mean intakes of calcium, phosphorus, and magnesium were 463.62 mg (66.23% of RDA), 955.32 mg (136.47% of RDA), 345.87 mg respectively. The mean serum levels of calcium, phosphorus and magnesium were 8.76 mg/dl, 3.80 mg/dl, and 2.10 mg/dl, respectively, and there were no significant differences among the three groups. However, the BMD of the femoral neck showed a significantly negative correlation with serum magnesium (p<0.05). To summarize the results, most nutrient intakes (especially calcium) in postmenopausal women did not reach the RDA values for Koreans. Also, increase of serum magnesium levels may be related to bone loss.


Subject(s)
Female , Humans , Male , Absorptiometry, Photon , Bone Density , Bone Diseases, Metabolic , Calcium , Estrogens , Femur Neck , Magnesium , Osteocalcin , Osteoporosis , Phosphorus , Risk Factors , Spine
20.
Korean Journal of Community Nutrition ; : 141-151, 2000.
Article in Korean | WPRIM | ID: wpr-205586

ABSTRACT

The purpose of this study was to compare food habits and nutrient intakes among high school students with different obesity indexes who are residing in Seoul and Kyunggi-do. a total of 533 subjects were assigned to one of the following groups based on BMI : underweight, normal-weight and overweight. Food habits and nutrient intakes were evaluated based on questionnaires and 24hr-dietary record. The results were as follows. There was no significant differences in the general environmental characteristics of subjects with different BMI. However, the father's BMI was significantly higher in overweight female students compared to underweight or normal weight subjects. The menarch age was significantly decreased as the obesity increased. The self-satisfaction score for physical type was decreased as the BMI increased. The overweight group skipped dinner more frequently the other groups among male students. There was no significant difference in the scores of nutrition knowledge, nutritional attitude, and self -satisfaction of subjects with different BMI. The nutrient intakes of overweight group were the lowest among the three groups. In conclusion, obesity among female students may be related to family member's obesity. Also overweight students tend to have lower self satisfaction for their body image and undesirable food habits. Therefore, proper nutrition education is required to maintain desirable food habits for overweight students.


Subject(s)
Female , Humans , Male , Body Image , Education , Feeding Behavior , Meals , Obesity , Overweight , Seoul , Thinness , Surveys and Questionnaires
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