• Journal of Life Science
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• v.26 no.2
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• pp.212-219
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• 2016

Glioblastoma multiforme is the most common and most aggressive type of primary brain tumor in humans. Despite intensive treatment, including surgery, radiation, and chemotherapy, most patients die of the disease. Although the anti-cancer activity of resveratrol has been demonstrated in various cancer cell types, its underlying mechanism in glioma cells is not fully elucidated. The present study was undertaken to investigate the effect of resveratrol on cell viability and to determine the molecular mechanism in A172 human glioma cells. Resveratrol caused the generation of reactive oxygen species (ROS), and resveratrol-induced cell death was prevented by antioxidants (N-acetylcysteine and catalase), suggesting that an oxidative mechanism is responsible for resveratrol-induced cell death. Resveratrol-induced phosphorylation of extracellular signal-regulated kinase (ERK), p38 kinase, and c-Jun N-terminal kinase (JNK), and resveratrol-induced cell death were prevented by inhibitors of these kinases. Resveratrol-induced activation of caspase-3 and cell death were prevented by the caspase inhibitors. ERK activation and caspase-3 activation induced by resveratrol was blocked by N-acetylcysteine. Taken together, these results suggest that resveratrol causes a caspase-dependent cell death via activation of ERK, p38, and JNK, mediated by ROS generation, in human glioma cells.

• Journal of Yeungnam Medical Science
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• v.7 no.1
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• pp.39-50
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• 1990

The one event on signalling mechanism is the cleavage by adenyl cyclase of ATP into second messenger, cyclic AMP. The other transfer system of inositol metabolism. it is widely recognized that hydrolysis of the minor membrane lipid phosphoinositide bisphosphate($PIP_2$) initiated by occupation of certain receptors and catalyzed by phospholipase C, lead to toe generation of the two intracellular messengers, inositol triphosphate($IP_3$) and diacylglycerol(DG). $IP_3$ is converted to inositol tetrakisphosphate($IP_4$) by $IP_3$ kinase. In the present study, it is that purification of calmodulin is used by phenyl-Sepharose CL-4B chromatography. it's molecular weigh, 17.000 in SDS-polyacrylamide gel electrophoresis. In order to observe the affinity between calmodulin (CaM)-Affigel 15 and $IP_3$ kinase, and isolated $IP_3$ kinase, was applied in CaM-Affigel with $Ca^{2+}$ equilibirum buffer and EGTA equilibirum buffer. We compared with binding and elution effect of $IP_3$ kinase in several condition of buffer. In affinity of binding. $Ca^{2+}$ equilibrium buffer was in the most proper condition. and elution, CaM/$Ca^{2+}$ buffer(CE1 10.36, CE2 12. 76pM/min/mg of protein) was effected much more than EGTA buffer(E2 1.48, E3 2.43pM/min/mg of protein), but CaM/$Ca^{2+}$ stimulate the activity of $IP_3$ kinase. And then, several detergents such as sodium deoxycholate, tween 20. cholic acid, polyethylene glycol, chaps were applied. The 0.2% chaps buffer(E2 23.19, E3 8.05pM/min/mg of protein) was the most effective in elution of $IP_3$ kinase.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.286-293
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• 2019

Alzheimer's disease (AD) is a neurodegenerative disease caused by accumulation of amyloid beta ($A{\beta}$) in the brain. In the present study, we investigated the neuroprotective effects of four flavonoids such as kaempferol, kaempferol-3-O-glucoside, quercetin, and quercetin-3-${\beta}$-D-glucoside against neuronal apoptosis induced by $A{\beta}$ in SH-SY5Y neuronal cells. Treatment with $A{\beta}$ decreased cell viability compared to the non-treated normal group. However, treatment with the four flavonoids increased cell viability in SH-SY5Y cells treated with $A{\beta}$. In addition, we measured the expression of apoptosis-related proteins such as Bcl-2-associated X protein (Bax) and cleaved caspase-9. Treatment with the four flavonoids down-regulated Bax and cleaved caspase-9 in $A{\beta}$-treated SH-SY5Y neuronal cells. Overall, the results of the present study demonstrated the neuroprotective effect of flavonoids by anti-apoptotic activity in $A{\beta}$-induced SH-SY5Y neuronal cells. These results suggest that these four flavonoids would be useful therapeutic and prevention agents for AD.

• 재활복지
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• v.22 no.3
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• pp.209-224
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• 2018

The purpose of this study is to provide a basic data about the virtual reality rehabilitation therapy to the occupational therapist in the domestic clinical field by systematically analyzing the types and effects of the rehabilitation therapy using the virtual reality program. Research articles were retrieved from January 2007 to December 2017 using the Research Information Sharing Service (RISS), Google Scholar, and Pubmed database. The main search terms were 'Virtual Reality AND Rehabilitation' and 'Virtual reality AND Effect'. Finally, 10 foreign studies were selected as the subjects of this study. Selected studies were organized using PICO (Patient, Intervention, Comparison, Outcome) format. The results were as follows: The subjects were divided into 4 types, stroke, brain tumor, Parkinson 's disease, and kidney disease. The tools used for arbitration were three IREX (30 %), two X-box Kinect (20 %), two Nintendo Wii (20 %), one [Existing tool + VR] (10 %), one [Mobile application + VR] (10 %). As a result of the intervention, improvement of function was observed in all 10 studies from overseas, and physical function was 24 times (66 %), mental function 6 times (17 %), cognitive function 5 times (14 %), Activity of daily living 1 time (10 %). this study could be used as a basic resource to enhance the professionalism and quality of rehabilitation services and expand the scope by organizing virtual reality-based rehabilitation and its effects.

• Journal of Life Science
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• v.29 no.8
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• pp.846-853
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• 2019

Phytochemical compounds of Ligusticum striatum Makino are used as traditional medicinal herbs in Asia. These compounds are reported to have pain relief and antioxidant activities in gynecological and brain diseases. In this study, we investigated the antioxidant effects of Ligusticum fermented ethanol extract from Lactobacillus plantarum BHN-LAB 129 isolated from Kimchi, a Korean traditional food. The total polyphenol and total flavonoid contents increased by about 116.2% and 281.0% respectively, in the fermented Ligusticum extract as compared with those in the nonfermented Ligusticum ethanol extract. Superoxide dismutase-like (SOD), DPPH radical scavenging, ABTS radical scavenging, and reducing power activities increased by around 139.9%, 199.6%, 301.0%, and 137.1%, respectively, in the fermented Ligusticum ethanol extract as compared with these parameters in the nonfermented Ligusticum ethanol extract, respectively. In conclusion, the fermented Ligusticum ethanol extract with L. plantarum BHN-LAB 129 was effective in increasing the antioxidant effects. The bioconversion process in this study points to the potential of using Ligusticum to produce phytochemical-enriched natural antioxidant agents with high added value. The findings may prove useful in the development of improved foods and cosmetic materials.

• Journal of Ginseng Research
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• v.46 no.6
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• pp.750-758
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• 2022

Background: Mild cognitive impairment (MCI) is a transitional condition between normality and dementia. Ginseng is known to have effects on attenuating cognitive deficits in neurogenerative diseases. Ginsenosides are the main bioactive component of ginseng, and their protein targets have not been fully understood. Furthermore, no thorough analysis is reported in ginsenoside-related protein targets in MCI. Methods: The candidate protein targets of ginsenosides in brain tissues were identified by drug affinity responsive target stability (DARTS) coupled with label-free liquid chromatography-mass spectrometry (LC-MS) analysis. Network pharmacology approach was used to collect the therapeutic targets for MCI. Based on the above-mentioned overlapping targets, we built up a proteineprotein interaction (PPI) network in STRING database and conducted gene ontology (GO) enrichment analysis. Finally, we assessed the effects of ginseng total saponins (GTS) and different ginsenosides on mitochondrial function by measuring the activity of the mitochondrial respiratory chain complex and performing molecular docking. Results: We screened 2526 MCI-related protein targets by databases and 349 ginsenoside-related protein targets by DARTS. On the basis of these 81 overlapping genes, enrichment analysis showed the mitochondria played an important role in GTS-mediated MCI pharmacological process. Mitochondrial function analysis showed GTS, protopanaxatriol (PPT), and Rd increased the activities of complex I in a dose-dependent manner. Molecular docking also predicted the docking pockets between PPT or Rd and mitochondrial respiratory chain complex I. Conclusion: This study indicated that ginsenosides might alleviate MCI by targeting respiratory chain complex I and regulating mitochondrial function, supporting ginseng's therapeutic application in cognitive deficits.

• Journal of Biomedical Engineering Research
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• v.43 no.1
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• pp.52-60
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• 2022

Purpose: For now, cognitive load is assessed based on survey-based methods, which can be difficult to track the amount of cognitive load in real-time. In this study, we investigated the difference in electrophysiological activation due to different levels of cognitive load not only at sensor-level but also at source-level using electroencephalogram that might be potentially used for quantitative cognitive load evaluation. Materials and Methods: In this study, ten healthy subjects (mean age 24.3 ± 2.1, three female) participated the experiment. All participants performed 4 sessions of n-back task in different difficulties: 0-, 1-, 2-, and 3-back during electroencephalogram recording. For sensor-level analysis, we calculated the event-related potential and event-related spectral perturbation while low resolution brain electromagnetic tomography (LORETA) to estimate the source activation. Each result was compared between different workload conditions using statistical analysis. Results: Statistical results revealed that the accuracy of the task performance was significantly different between different cognitive loads (p = 0.018). The post-hoc analysis confirmed that the accuracy of the 3-back task was significantly decreased compared to 1-back condition (p = 0.018), but not with 2-back condition (p = 0.180). ERP results showed that P300 target amplitude between 1-back and 3-back had a marginal difference in Cz (p = 0.059) and Pz(p = 0.093). A significant inhibition in Cz high-beta activation (p = 0.017) and decrease in source activation of right parahippocampal gyrus was found in 3-back condition compared to 1-back condition (p < 0.05). Conclusion: In this study, we compared the sensor- and source-level differences in electroencephalogram between different levels of cognitive load, that were found to be in line with the previous reports related to cognitive load evaluation. We expect that the outcome of the current study can be used as a feature to establish a quantitative cognitive load assessment system.

• Journal of the Korean Applied Science and Technology
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• v.41 no.1
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• pp.58-68
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• 2024

The purpose of this study was to investigate the effects of treadmill exercise treadmill exercise (TE) and environmental enrichment (EE) interventions on cognitive function, muscle function, and the expression of tight junction proteins in an Alzheimer's disease (AD) animal model. To create the AD animal model, aluminum chloride (AlCl₃) was administered for 90 days (40mg/kg/day), while simultaneously exposing the animals to TE (10-12m/min, 40-60min/day) or EE. The results showed that cognitive impairment and muscle dysfunction induced by AlCl₃ administration were alleviated by TE and EE. Furthermore, TE and EE reduced the increased expression of β-amyloid(Aβ), alpha-synuclein, and tumor necrosis factor-α (TNF-α) proteins observed in AD pathology. Additionally, TE and EE significantly increased the expression of decreased adhesive adjacent proteins (Occludin, Claudin-5, and ZO-1) induced by AlCl₃ administration. Lastly, correlation analysis between Aβ protein and tight junction proteins showed negative correlations (Occludin: r=-0.853, p=0.001; Claudin-5: r=-0.352, p=0.915; ZO-1: r=-0.424, p=0.0390). In conclusion, TE or EE interventions are considered effective exercise methods that partially alleviate pathological features of AD, improving cognitive and muscle function.

• The Korean Journal of Pharmacology
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• v.31 no.3
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• pp.299-311
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• 1995

Platelets resemble monoaminergic neurons in several respects, i.e. the uptake of 5-HT and its inhibition, the subcellular storage and release of 5-HT, and the metabolism of aromatic amines brought about by monoamine oxidase. And the 5-HT content of rabbit platelets is well known to be about 40 times higher than that of human platelets. Therefore, this study was carried out to investigate the influences of amitriptyline (AMT) and sertraline (SRT) on the aggregation, contents of signaling second messengers, and protein phosphorylations of rabbit platelets in response to thrombin, 0.25 unit/ml, comparing with those of chlorpromazine (CPZ). Thrombin-induced aggregation was inhibited by SRT $(IC50:4.37{\times}10^{-5}\;M)$, CPZ $(IC50:5.76{\times}10^{-5}\;M)$, and AMT $(IC50:1.15{\times}10^{-4}\;M)$, respectively, and the aggregation by A23187 $(1.0\;{\mu}M)$ or PMA (320 nM) was also inhibited by SRT, CPZ, and AMT. AMT, SRT, and CPZ had little affects on basal contents of platelet $TXB_2$ and $PGE_2$, but all of them inhibited the thrombin-induced increase of $TXB_2$. Thrombin did not change the platelet contents of cAMP and cGMP. CPZ, AMT, and SRT produced the slight decrease of basal cAMP content, and their effects were not affected by thrombin-treatment. But SRT and AMT moderately increased the basal cGMP content, and the cGMP content of thrombin-stimulated platelets was gradually increased by the pretreatment with SRT, AMT, and CPZ. Particularly, the SRT-dependent increase of the cGMP content was notable. Platelet $Ins(1,4,5)P_3$ content was rapidly increased up to a plateau within 10 sec after thrombin-stimulation, AMT, SRT, and CPZ increased the basal $Ins(1,4,5)P_3$ content, and the thrombin-dependent increase was enhanced by pretreatment with CPZ and AMT, but was blunted by SRT. Platelet $[Ca^{2+}]_i$, was rapidly increased up to a peak level within 20 sec after thrombin-stimulation. The increase of $[Ca^{2+}]_i$ was sisnificantly inhibited by AMT, SRT, and CPZ. Thrombin- or PMA-induced phosphorylations of platelet $41{\sim}43\;kDa$ and 20 kDa proteins were significantly inhibited by AMT, SRT, and CPZ. These results suggest that the antiplatelet activities of AMT and CPZ may be considerably attributed to the inhibition of protein kinase C activity, and the activity of SRT may be associated with the inhibitory effect on the thrombin-induced increase of $Ins(1,4,5)P_3$ and the increasing effect on the cGMP content of ptatelets. Therefore, it seems to be evident that AMT and SRT may produce their antidepressant activity, at least, partly through the inhibition of protein kinase C activity or the increase of resting $Ins(1,4,5)P_3$, content and in case of SRT, to a lesser extent, via the increase of cGMP in the brain.

• Progress in Medical Physics
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• v.18 no.3
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• pp.134-138
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• 2007

The current PET/CT system with high quality CT images not only increases diagnostic value by providing anatomic localization, but also shortens the acquisition time for attenuation correction than primary PET system. All commercially available PET/CT system uses the CT scan for attenuation correction instead of the transmission scan using radioactive source such as $^{137}Cs,\;^{68}Ge$. However the CT scan may substantially increase the patient dose. The purpose of this study was to evaluate quality of PET images reconstructed by CT attenuation map using various tube currents. in this study, images were acquired for 3D Hoffman brain phantom and cylindrical phantom using GE DSTe PET/CT system. The emission data were acquired for 10 min using phantoms after injecting 44.03 MBq of $^{18}F-FDG$. The CT images for attenuation map were acquired by changing tube current from 10 mA to 95 mA with fixed exposure time of 8 sec and fixed tube voltage of 140 kVp. The PET images were reconstructed using these CT attenuation maps. Image quality of CT images was evaluated by measuring SD (standard deviation) of cylindrical phantom which was filled with water and $^{18}F-FDG$ solution. The PET images were evaluated by measuring the activity ratio between gray matter and white matter in Hoffman phantom images. SDs of CT images decrease by increasing tube current. When PET images were reconstructed using CT attenuation maps with various tube currents, the activity ratios between gray matter and white matter of PET images were almost same. These results indicated that the quality of the PET images using low dose CT data were comparable to the PET images using general dose CT data. Therefore, the use of low dose CT is recommended than the use of general dose CT, when the diagnostic high quality CT is not required. Further studies may need to be performed for other system, since this study is limited to the GE DSTe system used in this study.