• International Journal of Oral Biology
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• v.33 no.2
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• pp.59-64
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• 2008

This study was designed to investigate the changes in the properties of the neuronal setm cells or progenitor cells associated with age-related decline in neurogenesis of the hippocampal dentate gyrus (DG). Active whole cells cycle marker Ki67 (a marker of whole cell cycle)-positive and S phase marker bromodeoxyuridine (BrdU)-positive. Neural stem cells gradually were reduced in the hippocampal subgranular zone (SGZ) in an age-dependant manner after birth (from P1 month to P1 year). The ratio of BrdUpositivecells/Ki67-positive cells was gradually enhanced in an age-dependent manner. The ratio of Ki67-positive cells/accu-mulating BrdU-positive cells at 3 hrs after BrdU injection was injected once a day for consecutive 5 days gradually decreased during ageing. TUNEL- and caspase 3 (apoptotic terminal caspase)-positive cells gradually decreased in the dentate SGZ during ageing and immunohistochemical findings of glial fibrillary acid protein (GFAP) were not changed during ageing. NeuN, a marker of mature neural cells, and BrdU-double positive cells gradually decreased in an age-dependent manner but differentiating ratio and survival rate of cells were not changed at 4 wks after BrdU injection once a day for consecutive 5 days. The number of BrdU-positive cells migrated from the hippocampal SGZ into granular layer and its migration speed was gradually declined during ageing. These results suggest that the adult neurogenesis in the mouse hippocampal DG gradually decrease through reducing proliferation of neural stem cells accompanying with cells cycle change and reduced cells migration rather than changes of differentiation.

• Journal of Sasang Constitutional Medicine
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• v.14 no.1
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• pp.79-89
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• 2002

To evaluate the effect of Yuldahansotang(YHT) water extract on cultured hippocampal cell was inhibited by hydrogen peroxide, MTT assay, NR assay, Neurofilament enzymeimmuno assay and DNA synthesis assay were carried out after the cultured hippocampal cells were preincubated with various concentrations of YHT water extract for 3 hours prior to exposure of hydrogen peroxide. The results obtained were as follows: 1. Hydrogen Peroxide decreased the survival rate of the cultured hippocampal cells on NR assay and MIT assay. 2. YHT water extract have efficacy of increasing a amount of neurofilament decreased by hydrogen peroxide in cultured hippocampal cells. 3. YHT water extract have efficacy of increasing DNA synthesis decreased by hydrogen peroxide in cultured hippocampal cells. From above the results, It is concluded that YHT has marked efficacy in preventing for the damages by hydrogen peroxide.

• Journal of Sasang Constitutional Medicine
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• v.14 no.1
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• pp.67-78
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• 2002

Jowiseungcheongtang(JST) has been in Sasang constitution medicine for many years as a therapeutic agent for cerebral disease. But the effect of Jowiseungcheongtang(JST) on neurotoxicity is not known. The purpose of this study was to determine the effects of Jowiseungcheongtang(JST) on the hippocampal cell injured by Xanthine Oxidase/Hypoxanthine. The results were as follows: 1. XO/HX decreased the survival rate of the cultured hippocampal cells on NR assay and MTT assay. 2. JST water extract have efficacy of decreasing a amount of lipid peroxidation increased by XO/HX in cultured hippocampal cells. 3. JST water extract have efficacy of increasing DNA synthesis decreased by XO/HX in cultured hippocampal cells. From the above results, It is concluded that JST has marked efficacy in preventing cultured hippocampal cells from the damages by XO/HX.

• Toxicological Research
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• v.27 no.2
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• pp.103-110
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• 2011

Lipotoxicity involves pathological alterations to cells and tissues in response to elevated fat levels in blood. Furthermore, this process can disturb both cellular homeostasis and viability. In the current study, the authors show that neural progenitor cells (NPCs) are vulnerable to high levels of palmitic acid (PA) a saturated fatty acid. PA was found to cause cell death associated with elevated reactive oxygen species (ROS) levels, and to reduce NPCs proliferation. To evaluate the lipotoxicity of PA in adult NPCs in the hippocampus, male C57BL/6 mice were divided into two groups and maintained on either a normal diet (ND) or PA-rich high fat diet (HFD) for 2 weeks. Interestingly, short-term PA-rich HFD feeding reduced the survival of newly generated cells in the hippocampal dentate gyrus and hippocampal brain-derived neurotrophic factor levels. These findings suggest PA has a potent lipotoxicity in NPCs and that a PA-rich HFD disrupts hippocampal neurogenesis.

• Animal cells and systems
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• v.12 no.4
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• pp.203-209
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• 2008

Berberine, an isoquinoline alkaloid found in Coptidis Rhizoma(goldenthread) extract, has multiple pharmacological effects such as anti-inflammatory, antimicrobial and anti-ischemic effects. In the present study, we examined the effects of berberine on neuronal survival and differentiation in a hippocampal precursor cell line and in the memory deficient rat model. Berberine increased in a dose dependent manner the survival of hippocampal precursor cells as well as differentiated cells. In addition, berberine promoted neuronal differentiation of hippocampal precursor cells. In the memory deficient rat model induced by stereotaxic injection of ibotenic acid into entorhinal cortex(Ibo model), hippocampal cells were increased about 2.7 fold in the pyramidal layer of CA1 region and about 2 fold in the dentate gyrus by administration of berberine after 2 weeks of ibotenic acid injection. Furthermore, neuronal cells immunoreactive to calbindin were increased in the hippocampus and entorhinal cortex area by administration of berberine. Taken together, these results suggest that berberine has neuroprotective effect in the Ibo model rat brain by promoting the neuronal survival and differentiation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.4
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• pp.771-777
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• 2008

Chungpaesagan-tang which is used for treating patients of brain in cerebrovascular disease frequently from clinical doctor has not reported about the effect of neuronal aptosis caused of brain ischemia. The aim of this study is to investigate effect of Chungpaesagan-tang protecting neuronal cells from being damaged by brain ischemia through using organotypic hippocampal slice cultures. We caused ischemic damage to organotypic hippocampal slice cultures by oxygen and glucose deprivation. And added Chungpaesagan-tang extract to cultures. thereafter we measured area percentage of propidium iodide (PI)-stained neuronal cell, lactate dehydrogenase (LDH) levels in culture media and Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells. Area percentage of PI-stained neuronal cells and count of TUNEL-positive cells in CA1 and DG area of organotypic hippocampal slice culture were significantly decreased in pertinent density level of Chungpaesagan-tang extract. LDH levels in culture media of organotypic hippocampal slice culture were significantly decreased in pertinent density level of Chungpaesagan-tang extract. Within pertinent density level, Chungpaesagan-tang has cell protection effect that prevents brain ischemia damaging neuronal cells and apoptosis increasing.

• The Journal of Internal Korean Medicine
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• v.29 no.1
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• pp.231-242
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• 2008

Objectives : We can find out the experimental reports of Yanggyuksanhwa-tang, which has the function of regulating blood pressure related with cerebral disease, and increasing local cerebral blood stream volume, also has the recoveries for the damage of vessel endothelium, and endothelium hypertrophy caused by angiospasm after subarachnoid hemorrhage, and reduces the contraction of smooth muscle, so simultaneously improves necrosis. The aim of this study is to investigate effect of Yanggyuksanhwa-tang protecting neuronal cells from being damaged by brain ischemia through using organotypic hippocampal slice cultures. Methods : We caused ischemic damage to organotypic hippocampal slice cultures by oxygen and glucose deprivation, and Yanggyuksanhwa-tang extract was added to cultures. Thereafter we measured area percentage of propidium iodide (PI)-stained neuronal cell, lactate dehydrogenase (LDH) levels in culture media and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells. Results : Area percentage of PI-stained neuronal cells and count of TUNEL-positive cells in CA1 and DG area of organotypic hippocampal slice culture were significantly decreased in pertinent density level of Yanggyuksanhwa-tang extract. LDH levels in culture media of organotypic hippocampal slice culture were significantly decreased in pertinent density level of Yanggyuksanhwa-tang extract. Conclusions : Within pertinent density level, Yanggyuksanhwa-tang has cell protection effect that prevents brain ischemia damaging neuronal cells and apoptosis increasing.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.4
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• pp.281-285
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• 2012

A previous animal study has shown the effects of erythropoietin (EPO) and its non-erythropoietic carbamylated derivative (CEPO) on neurogenesis in the dentate gyrus. In the present study, we sought to investigate the effect of EPO on adult hippocampal neurogenesis, and to compare the ability of EPO and CEPO promoting dendrite elongation in cultured hippocampal neural progenitor cells. Two-month-old male BALB/c mice were given daily injections of EPO (5 U/g) for seven days and were sacrificed 12 hours after the final injection. Proliferation assays demonstrated that EPO treatment increased the density of bromodeoxyuridine (BrdU)-labeled cells in the subgranular zone (SGZ) compared to that in vehicle-treated controls. Functional differentiation studies using dissociated hippocampal cultures revealed that EPO treatment also increased the number of double-labeled BrdU/microtubulea-ssociated protein 2 (MAP2) neurons compared to those in vehicle-treated controls. Both EPO and CEPO treatment significantly increased the length of neurites and spine density in MAP2(+) cells. In summary, these results provide evidences that EPO and CEPO promote adult hippocampal neurogenesis and neuronal differentiation. These suggest that EPO and CEPO could be a good candidate for treating neuropsychiatric disorders such as depression and anxiety associated with neuronal atrophy and reduced hippocampal neurogenesis.

• The Journal of Korean Medicine
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• v.29 no.5
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• pp.29-40
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• 2008

Objectives : It has been reported that Sophorae Subprostratae Radix (SSR) has a neuroprotective effect on cerebral ischemia in animals. In the present study, the authors investigated the neuroprotective effect of SSR on glutamate excitotoxicity. Glutamate excitotoxicity was induced by using NMDA, AMPA, and KA in PC12 cells and in organotypic hippocampal slice cultures. Methods :Methanolic extract of SSR was added at 0.5, 5, and 50 ${\mu}$g/ml to culture media for 24 hours. The effects of SSR were evaluated by measuring of cell viability, PI-stained neuronal cell death, TUNEL-positive cells, and MAP-2 immunoreactivity. Results : SSR increased PC12 cell viabilities significantly against AMPA-induced excitotoxicity, but not against NMDA-induced or KA-induced excitotoxicity. In organotypic hippocampal slice cultures damaged by NMDA-induced excitotoxicity, SSR attenuated neuronal cell death significantly in the CA1, CA3, and DG hippocampal regions and reduced TUNEL-positive cells significantly in CA1 and DG regions. In organotypic hippocampal slice cultures damaged by AMPA-induced excitotoxicity, SSR attenuated neuronal cell death and reduced TUNEL-positive cell numbers significantly in the CA1 and DG regions. In organotypic hippocampal slice cultures damaged by KA-induced excitotoxicity, SSR attenuated neuronal cell death significantly in CA3, but did not reduce TUNEL-positive cell numbers in CA1, CA3 or DG. In organotypic hippocampal slice cultures damaged by NMDA-induced excitotoxicity, SSR attenuated pyramidal neuron neurite retraction and degeneration in CA1. Conclusions : These results suggest that the neuroprotective effects of SSR are related to antagonistic effects on the NMDA and AMPA receptors of neuronal cells damaged by excitotoxicity and ischemia.

• Toxicological Research
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• v.6 no.2
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• pp.191-204
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• 1990

Trimethyltin (TMT) induced lesions in the rat hippocampal formation was reviewed. Adult rats were treated with a single dose of 6.0 mg TMT/kg b.w. and were sacrificed between 3-60 days following exposure. On the hippocampal formation, the granule cells of fascia dentata showed early changes which subsided considerably at a later time when the destruction of the pyramidal neurons of the Ammon's horn became increasingly pronounced with time, leading to severe destruction of the structure. It is interesting to note that there was an inverse relationship of pathological involvement between the f.d. granule cells and the Ammon's horn neurons; i.e., when there was a large sparing of the granule cells. there was an extensive damage to the Ammon's horn and vice versa. This inverse relationship was also true between the $CA_3$neurons and the $CA_{1,2}$neurons in the Ammon's horn. Progressive zinc loss, as demonstrated by Timm's method, on the Mossy fibers was also observed. Similar Mossy fiber zinc depletion has been demonstrated in electrical stimulatory excitation condition of the perforant path to the hippocampus. Depletion of corticosterone, an inhibitor to the hippocampal neurons, by means of adrenalectomy will exaggerate the TMT induced hippocampal lesion. Neonatal study revealed that a unique degenerative pattern of the Ammon's horn could be established in accordance with exposure to TMT at specific maturation periods of the fippocampal formation: increasing destruction of the Ammon's horn with increasing synaptogenesis between the f.d. granule cells and the Ammon's horn neurons. Thus it is apparent that the damage of the Ammon's horn, upon exposure to TMT, may depend on the integrity and functional state of the f.d. granule cells. A hyperexcitory scheme and mechanism as the toxicity basis of TMT in the hippocampal formation is proposed and discussed.