• Biomolecules & Therapeutics
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• v.15 no.1
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• pp.16-26
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• 2007

Tissue plasminogen activator (tPA) is a serine protease catalyzing the proteolytic conversion of plasminogen into plasmin, which is involved in thrombolysis. During last two decades, the role of tPA in brain physiology and pathology has been extensively investigated. tPA is expressed in brain regions such as cortex, hippocampus, amygdala and cerebellum, and major neural cell types such as neuron, astrocyte, microglia and endothelial cells express tPA in basal status. After strong neural stimulation such as seizure, tPA behaves as an immediate early gene increasing the expression level within an hour. Neural activity and/or postsynaptic stimulation increased the release of tPA from axonal terminal and presumably from dendritic compartment. Neuronal tPA regulates plastic changes in neuronal function and structure mediating key neurologic processes such as visual cortex plasticity, seizure spreading, cerebellar motor learning, long term potentiation and addictive or withdrawal behavior after morphine discontinuance. In addition to these physiological roles, tPA mediates excitotoxicity leading to the neurodegeneration in several pathological conditions including ischemic stroke. Increasing amount of evidence also suggest the role of tPA in neurodegenerative diseases such as Alzheimer's disease and multiple sclerosis even though beneficial effects was also reported in case of Alzheimer's disease based on the observation of tPA-induced degradation of $A{\beta}$ aggregates. Target proteins of tPA action include extracellular matrix protein laminin, proteoglycans and NMDA receptor. In addition, several receptors (or binding partners) for tPA has been reported such as low-density lipoprotein receptor-related protein (LRP) and annexin II, even though intracellular signaling mechanism underlying tPA action is not clear yet. Interestingly, the action of tPA comprises both proteolytic and non-proteolytic mechanism. In case of microglial activation, tPA showed non-proteolytic cytokine-like function. The search for exact target proteins and receptor molecules for tPA along with the identification of the mechanism regulating tPA expression and release in the nervous system will enable us to better understand several key neurological processes like teaming and memory as well as to obtain therapeutic tools against neurodegenerative diseases.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.637-642
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• 2004

Effects of defatted sesame and perilla methanol extracts on cognitive function and antioxidant activity of learning- and memory-impaired animal model SAMP8 mice. Animals were divided into 4 groups and fed with diets containing 0.3%(w/w) defatted sesame (S) or defatted perilla methanol extracts (P) for 12 weeks. Step through latency of SAMP8 control group was significantly higher than that of SAM R1 normal group, whereas significantly increased in S and P groups compared with SAMP8 control on passive avoidance test (p<0.001). Acetylcholinesterase activity of brain in SAMP8 increased compared with SAMR1 but no difference between SAMP8 control group and sample-treated group. Brain TBARS contents of SAMP8 control significantly increased compared with SAMR1 and were lowered significantly by supplementation of defatted sesame and perilla methanol extracts. Defatted sesame and perilla methanol extracts attenuated increased brain superoxide dismutase and glutathione peroxidase activities in SAMP8. These results suggest defatted sesame and perilla methanol extracts could attenuate cognitive deficits induced by aging possibly through activation of antioxidant activity of defatted sesame and perilla methanol extracts.

• Journal of Nutrition and Health
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• v.37 no.2
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• pp.95-99
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• 2004

This study was designed to investigate the effects of ethyl acetate(EtOAc) fraction of pine (Pinus densiflora Sieb et Zucc) needle on cholesterol and lipofuscin(LF) accumulations, acetylcholine(ACh) and its related enzyme activities such as choline acetyltransferase(ChAT) and acetylcholinesterase(AChE), and monoamine oxidase-B(MAO-B) activity, which destroyed the catecholamine related neurotransmitters in brain membranes of Sprague- Dawley (SD) rats. Male SD rats were fed basic diets (control group) and experimental diets (EtOAc-25, EtOAc-50 and EtOAc-100) for 45 days. Cholesterol accumulations in mitocholndria and microsomes were significantly inhibited (11.8-12.1% and 9.6-13.0%, respectvely) in EtOAc-50 and EtOAc-100 groups. ACh levels and ChAT activities were significantly increased about 10% in membranes of EtOAc-100 group compared with control group. AChE activities were significantly increased about 8 -12% in membranes of EtOAc-50 and EtOAc-100 groups compared with control group. MAO-B activities were significantly inhibited about 10% in membrane of EtOAc-l00 group compared with control group. These results suggest that ethyl acetate fraction of pine needle may play an effective role in inhibiting cholesterol and improving a membrane fluidity, and learning and memory impairments. (Korean J Nutrition 37(2): 95 -99, 2004)

• Journal of Life Science
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• v.32 no.5
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• pp.362-367
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• 2022

Hempseed, a dehulled Cannabis fructus, has high nutraceutical potential. It has plenty of essential amino acids, vitamins, and essential polyunsaturated fatty acids, including α- and γ-linolenic acid. Increased exercise capacity, cognitive function, and ameliorative effects against hypercholesterolemia, neuro-inflammation, thrombus formation, and learning and memory impairment were reported in hemp-seed oil-administered models. Therefore, the market prices of hempseed oil are 45~140-fold higher than the other plant-derived oils, such as soy, corn, olive, canola, or linseed oil. In this study, instead of FTIR (Fourier Transform Infrared Spectroscopy) or FTIR-Raman spectroscopy, a simple UV-Vis spectrophotometry method was developed to authenticate the hempseed oil. Measurements of absorbance at 245, 305, and 415 nm of oils and calculations of 245/415 and 315/415 nm provided that the ratios of 245/415 and 315/415 nm of authentic hempseed oils were 12.9 and 9.6, respectively. The 245/415 and 315/415 nm of soy oil, corn oil, canola oil, and linseed oil were 35.4~61.8 and 29.7~50.8, respectively. This simple UV-Vis spectrophotometry method could also be applied to differentiate hempseed oil from blended oil products in markets.

• International Journal of Advanced Culture Technology
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• v.5 no.3
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• pp.11-23
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• 2017

Anatomy is one of the basic subjects of the nursing course, which is included in the curriculum of the nursing. Anatomy is a basic course for understanding major in nursing and it is the first gateway to acquire expertise. It is mainly opened in nursing and first to second grades. Therefore, students who have advanced to the nursing department have great interest and expectation on the anatomy subjects. In general, nursing students are studying anatomy with theories and models, and some universities practice on tour after dissection of medical consortium for short time. This is called the Cadaver practice. This study was carried out to investigate the thoughts and experiences of bioethics through nursing students' Cadaver practice. The interview data were processed through the analysis and interpretation process using the phenomenological research method, Giorgi method. As a result, 48 semantic units were derived, and then they were divided into 10 subcomponents and divided into 6 categories. As a result of the analysis, the experience of nursing students' bioethics was tied to the topic of six questions. For example, 'what about the respect and responsibility of nursing students in Cadaver?', 'What about your experience with the Cadaver experiment and bioethics?', 'What was the academic achievement of the actual human body structure viewing experience with cadaver?', 'What was the connection with theory?', 'What was your intention to recommend to others?', 'What was your perception and interest in the Cadaver experiment?'. Analyzes were integrated into 10 structures; "Thank you for your donation", "want others to refuse donation", "Burden of practice", "Good opportunities for learning", "Understand better", "Should study harder", "Memory is better", "Compared to theory", "Good experience", "Want to rejoin". The general structural description of the participants' meanings is summarized as follows. Nursing college students who participated in the Cadaver had a gratitude for the donor, but they said they would like to talk to others about donating organs. Before they went to practice, they felt a lot of pressure on the dissection of the cadaver, but they went to the practice and thought that it was a good opportunity to learn by doing well. Specifically, they understood that they had better understanding than the theoretical lesson, and that they were more eager to study their major through practice. In other words, most of them were more memorable and they would like to participate again if the opportunity comes next time. The results of this study show that the practice of Cadaver in nursing college students is very positive in terms of educational effectiveness. However, in terms of bioethics, it can be seen that the education process is somewhat unsatisfactory. Therefore, the systematic bioethics education should be prepared before the practice in the nursing college students' Cadaver practice.

• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.373-379
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• 2015

This study aimed to investigate the anti-amnesic effect of perilla oil against trimethyltin (TMT)-induced learning and memory impairment in ICR mice. Perilla oil (2.5 mL/kg of body weight) and soybean oil (2.5 mL/kg of body weight) were administered orally to mice for 3 weeks, and at the end of the experimental period, cognitive behavior was examined by Y-maze and Morris water maze (MWM) tests. Behavioral tests showed that the mice treated with perilla oil had improved cognitive function compared to that in mice administered soybean oil. Analysis of brain tissue showed that perilla oil significantly lowered acetylcholinesterase activity and malondialdehyde (MDA) levels. Oxidized glutathione (GSH)-to-total GSH ratio also decreased from 10.4% to 5.3% in perilla oil-treated mice, but superoxide dismutase (SOD) activity increased from 11.7 to 14.2 U/mg protein. Therefore, these results suggest that the perilla oil could be a potential functional substance for improving cognitive function.

• The Journal of Internal Korean Medicine
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• v.35 no.1
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• pp.37-49
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• 2014

Objectives & Methods : The objective of this study was to evaluate the single oral dose toxicity of Chongmyung-tang (CMT) in ICR mice. Korean traditional herbal prescription CMT has traditionally been used as a neuroprotective for treatment of learning disability and memory improvement. CMT, lyophilized aqueous extracts (yield=9.7%) were administered to female and male mice with oral dose of 2,000, 1,000 and 500 mg/kg (body weight) according to the recommendation of Korea Food and Drug Administration (KFDA) Guidelines. Animals were monitored for mortality, changes in body weight, clinical signs and gross observation during 14 days after administration upon necropsy; organ weight and histopathology of 14 principle organs were examined. Results : We could not find any CMT extracts treatment related mortalities, clinical signs, changes in body and organ weight, or gross and histopathological observations against 14 principle organs up to 2,000 mg/kg in both female and male mice, except for some accidental sporadic findings which did not show any obvious dose-relations and most of which also demonstrated in both the female and male vehicle control mice in this experiments. Conclusions : Based on the results of this experiment, the 50% lethal dose ($LD_{50}$) and approximate lethal dose (ALD) of CMT extracts after single oral treatment in female and male mice can be considered to be over 2,000 mg/kg, and is likely to be safe in humans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.738-742
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• 2005

This study was designed to investigate the anti-dementia effects of acorn (Quercus acutissima CARR.) in brain of the mouse. Dementia model was induced by administration of scopolamin (30 mg/kg BW) Male ICR mouse $(30{\pm}2g\;BW)$ were fed basal diet (control group), and experimental diets (AP-5 and AP-10 groups) added $5\%\;and\;10\%$ of dried acorn powder to basal diet for 8 months. Acetylcholine content significantly increase in AP-5 and AP-10 groups ($4.2\%\;and\;11.3\%$, respectively) compared with control group. Acetylcholinesterase activities were significantly inhibited ($13.5\%\;and\;17.6\%$, respectively) in brain of AP-5 and AP-10 groups. Monoamine oxidase-B (MAO-B) activities were significantly inhibited ($10.0\%\;and\;12.7\%$, respectively) in brain of AP-S and AP-10 groups. These results suggest that acorn (Q. acutissima CARR.) may play an effective role in an attenuating various age-related changes such as dementia including learning and memory impairments in brain.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.1
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• pp.11-18
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• 2020

The present study was aimed to explore the neuroprotective role of imatinib in global ischemia-reperfusion-induced cerebral injury along with possible mechanisms. Global ischemia was induced in mice by bilateral carotid artery occlusion for 20 min, which was followed by reperfusion for 24 h by restoring the blood flow to the brain. The extent of cerebral injury was assessed after 24 h of global ischemia by measuring the locomotor activity (actophotometer test), motor coordination (inclined beam walking test), neurological severity score, learning and memory (object recognition test) and cerebral infarction (triphenyl tetrazolium chloride stain). Ischemia-reperfusion injury produced significant cerebral infarction, impaired the behavioral parameters and decreased the expression of connexin 43 and phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in the brain. A single dose administration of imatinib (20 and 40 mg/kg) attenuated ischemia-reperfusion-induced behavioral deficits and the extent of cerebral infarction along with the restoration of connexin 43 and p-STAT3 levels. However, administration of AG490, a selective Janus-activated kinase 2 (JAK2)/STAT3 inhibitor, abolished the neuroprotective actions of imatinib and decreased the expression of connexin 43 and p-STAT3. It is concluded that imatinib has the potential of attenuating global ischemia-reperfusion-induced cerebral injury, which may be possibly attributed to activation of JAK2/STAT3 signaling pathway along with the increase in the expression of connexin 43.

• The Korea Journal of Herbology
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• v.31 no.1
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• pp.7-15
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• 2016

Objectives : Polygalae Radix (POL) has an ameliorating effect on learning and memory impairment caused by cerebral hypoperfusion. In regard to POL's action mechanism, this study was carried out to investigate the effects of POL on oxidative damage and neuronal apoptosis induced by cerebral hypoperfusion in rats.Methods : The cerebral hypoperfusion was induced by permanent bilateral common carotid artery occlusion (pBCAO) in Sprague-Dawley rats. POL was administered orally once a day (130 mg/kg of water-extract) for 28 days starting at 4 weeks after the pBCAO. Superoxide dismutase (SOD) activities and malondialdehyde (MDA) levels in the brain tissue were measured using ELISA method. Expressions of 4-hydroxynonenal (4HNE) and 8-hydroxy-2'- deoxyguanosine (8-OHdG) were observed using immunohistochemistry. In addition, neuronal apoptosis was evaluated with Cresyl violet staining, TUNEL labeling, and immunohistochemistry against Bax and caspase-3.Results : POL treatment significantly increased SOD activities and significantly reduced MDA levels in the cerebral cortex. The up-regulations of 4HNE and 8-OHdG expression caused by pBCAO in the CA1 of hippocampus were significantly attenuated by POL treatment. POL treatment also restored the reduction of CA1 thickness and CA1 neurons caused by pBCAO and significantly attenuated the apoptotic markers including TUNEL-positive cells, Bax, and caspase-3 expression in the CA1 of hippocampus.Conclusions : The results show that POL attenuated the oxidative damage in brain tissue and neuronal apoptosis in the hippocampus caused by the cerebral hypoperfusion. It suggests that POL can be a beneficial medicinal herb to treat the brain diseases related to cerebral hypoperfusion.