1.(3H)MK-801 binding to the synaptic membranes of rat forebrains: Age-related regulation by glutamate, glycine and spermine.
The Korean Journal of Physiology and Pharmacology 1997;1(2):117-125
The N-methyl-D-aspartate (NMDA) receptor-mediated glutamatergic neurotransmission is involved in synaptic plasticity, developmental processes, learning and memory and many neuropathological disorders including age-related diseases. In the present study, regulation of the NMDA receptor properties by various ligands was investigated using (3H)MK-801 binding studies in the synaptic membranes of young and aged rat forebrains. The binding in the presence of glutamate and glycine increased dramatically with growth between 1 and 6 weeks old, and thereafter declined gradually with aging. Glutamate, glycine or spermine respectively increased the binding with growth. Glutamate maintained the binding during aging, while glycine or spermine significantly decreased the binding in the aged brain. The maximum stimulation by glycine varied depending on the ages of brains. Greater sensitivity to glycine was observed at 1 week and 3 months and the sensitivity was significantly reduced in the aged brain. In contrast, spermine showed similar stimulation patterns in young and aged rats. These results indicated that the functional properties of the NMDA receptor-ion channel complex in young and aged rat forebrains are differentially regulated by agonists, and the reduction of the receptor function with normal aging may be, in some degree, due to the reduction of the receptor sensitivity to glycine.
Aging
;
Animals
;
Brain
;
Dizocilpine Maleate
;
Glutamic Acid*
;
Glycine*
;
Learning
;
Ligands
;
Memory
;
N-Methylaspartate
;
Plastics
;
Prosencephalon*
;
Rats*
;
Spermine*
;
Synaptic Membranes*
;
Synaptic Transmission
2.Tumour Regression via Integrative Regulation of Neurological, Inflammatory, and Hypoxic Tumour Microenvironment
Chang Hoon LEE ; Jungsook CHO ; Kyeong LEE
Biomolecules & Therapeutics 2020;28(2):119-130
Changing trends in anticancer research have altered the treatment paradigm to the extent that it is difficult to investigate any anticancer drugs without mentioning immunotherapy. Thus, we are finally contemplating tumour regression using magic bullets known as immunotherapy drugs. This review explores the possible options and pitfalls in tumour regression by first elucidating the features of cancer and the importance of tumour microenvironments. Next, we evaluated the trends of anticancer therapeutics regulating tumour microenvironment. Finally, we introduced the concept of tumour regression and various targets of tumour microenvironment, which can be used in combination with current immunotherapy for tumour regression. In particular, we emphasize the importance of regulating the neurological manifestations of tumour microenvironment (N) in addition to inflammation (I) and hypoxia (H) in cancer.
3.A Study on the Use of Physical Restraints in ICUs.
Yongae CHO ; Jungsook KIM ; Nari KIM ; Heejung CHOI ; Junggu CHO ; Heejung LEE ; Ryungin KIM ; Younghee SUNG
Journal of Korean Academy of Adult Nursing 2006;18(4):543-552
PURPOSE: The purpose of this descriptive study was to investigate the pattern of physical restraints used in ICUs and to identify influencing factors of application and removal of restraints. METHOD: The subjects of this study were 90 restrained patients out of 215 patients over 6 years old who were admitted to 6 ICUs in SMC during a 2 weeks period. The data was collected through a questionnaire of characte-ristics, guidelines and nursing care of restraint uses. The data were analyzed by non-parametric statistic with the use of the SAS program. RESULTS: The restraints were applied to 31.4% of subjects. Mean time of physical restraint was 36.76 55.7 hours. There were significant difference with mean time and frequency according to duty shift. GCS, restless behavior and discomfort factors, medical devices, and life sustaining devices had significant relation with application of restraints. In addition, the mean time of restraints used were related significantly with GCS, restless behavior, and discomfort factors. CONCLUSION: The used of restraints were dependent on mainly the nurses' decision. Thus ICU nurses have to develop the guidelines to applying restraints and removal of restraints in regard to patients rights and ethics. Continuous monitoring and evaluation of application of the restraints is essential in professional nursing.
Child
;
Ethics
;
Humans
;
Intensive Care Units
;
Nursing
;
Nursing Care
;
Patient Rights
;
Restraint, Physical*
;
Surveys and Questionnaires
4.Neuroprotective and Antioxidant Effects of Novel Benzofuran-2-Carboxamide Derivatives.
Jungsook CHO ; Chowee PARK ; Youngmun LEE ; Sunyoung KIM ; Shambhunath BOSE ; Minho CHOI ; Arepalli Sateesh KUMAR ; Jae Kyung JUNG ; Heesoon LEE
Biomolecules & Therapeutics 2015;23(3):275-282
In the present study, we synthesized a series of novel 7-methoxy-N-(substituted phenyl)benzofuran-2-carboxamide derivatives in moderate to good yields and evaluated their neuroprotective and antioxidant activities using primary cultured rat cortical neuronal cells and in vitro cell-free bioassays. Based on our primary screening data with eighteen synthesized derivatives, nine compounds (1a, 1c, 1f, 1i, 1j, 1l, 1p, 1q and 1r) exhibiting considerable protection against the NMDA-induced excitotoxic neuronal cell damage at the concentration of 100 muM were selected for further evaluation. Among the selected derivatives, compound 1f (with -CH3 substitution at R2 position) exhibited the most potent and efficacious neuroprotective action against the NMDA-induced excitotoxicity. Its neuroprotective effect was almost comparable to that of memantine, a well-known NMDA antagonist, at 30 muM concentration. In addition to 1f, compound 1j (with -OH substitution at R3 position) also showed marked anti-excitotoxic effects at both 100 and 300 muM concentrations. These findings suggest that -CH3 substitution at R2 position and, to a lesser degree, -OH substitution at R3 position may be important for exhibiting neuroprotective action against excitotoxic damage. Compound 1j was also found to scavenge 1,1-diphenyl-2-picrylhydrazyl radicals and inhibit in vitro lipid peroxidation in rat brain homogenate in moderate and appreciable degrees. Taken together, our structure-activity relationship studies suggest that the compound with -CH3 substitution at R2 and -OH substitution at R3 positions of the benzofuran moiety might serve as the lead exhibiting potent anti-excitotoxic, ROS scavenging, and antioxidant activities. Further synthesis and evaluation will be necessary to confirm this possibility.
Animals
;
Antioxidants*
;
Biological Assay
;
Brain
;
Lipid Peroxidation
;
Mass Screening
;
Memantine
;
N-Methylaspartate
;
Neurons
;
Neuroprotective Agents
;
Rats
;
Reactive Oxygen Species
;
Structure-Activity Relationship
5.Efonidipine Inhibits JNK and NF-κB Pathway to Attenuate Inflammation and Cell Migration Induced by Lipopolysaccharide in Microglial Cells
Ngoc Minh NGUYEN ; Men Thi Hoai DUONG ; Phuong Linh NGUYEN ; Bich Phuong BUI ; Hee-Chul AHN ; Jungsook CHO
Biomolecules & Therapeutics 2022;30(5):455-464
Efonidipine, a calcium channel blocker, is widely used for the treatment of hypertension and cardiovascular diseases. In our preliminary study using structure-based virtual screening, efonidipine was identified as a potential inhibitor of c-Jun N-terminal kinase 3 (JNK3). Although its antihypertensive effect is widely known, the role of efonidipine in the central nervous system has remained elusive. The present study investigated the effects of efonidipine on the inflammation and cell migration induced by lipopolysaccharide (LPS) using murine BV2 and human HMC3 microglial cell lines and elucidated signaling molecules mediating its effects. We found that the phosphorylations of JNK and its downstream molecule c-Jun in LPS-treated BV2 cells were declined by efonidipine, confirming the finding from virtual screening. In addition, efonidipine inhibited the LPS-induced production of pro-inflammatory factors, including interleukin-1β (IL-1β) and nitric oxide. Similarly, the IL-1β production in LPS-treated HMC3 cells was also inhibited by efonidipine. Efonidipine markedly impeded cell migration stimulated by LPS in both cells. Furthermore, it inhibited the phosphorylation of inhibitor kappa B, thereby suppressing nuclear translocation of nuclear factor-κB (NF-κB) in LPS-treated BV2 cells. Taken together, efonidipine exerts anti-inflammatory and anti-migratory effects in LPS-treated microglial cells through inhibition of the JNK/NF-κB pathway. These findings imply that efonidipine may be a potential candidate for drug repositioning, with beneficial impacts on brain disorders associated with neuroinflammation.
6.Loss of EMP2 Inhibits Melanogenesis of MNT1 Melanoma Cells via Regulation of TRP-2
Enkhmend ENKHTAIVAN ; Hyun Ji KIM ; Boram KIM ; Hyung Jung BYUN ; Lu YU ; Tuan Minh NGUYEN ; Thi Ha NGUYEN ; Phuong Anh DO ; Eun Ji KIM ; Kyung Sung KIM ; Hiệu Phùng HUY ; Mostafizur RAHMAN ; Ji Yun JANG ; Seung Bae RHO ; Ho LEE ; Gyeoung Jin KANG ; Mi Kyung PARK ; Nan-Hyung KIM ; Chang Ick CHOI ; Kyeong LEE ; Hyo Kyung HAN ; Jungsook CHO ; Ai Young LEE ; Chang Hoon LEE
Biomolecules & Therapeutics 2022;30(2):203-211
Melanogenesis is the production of melanin from tyrosine by a series of enzyme-catalyzed reactions, in which tyrosinase and DOPA oxidase play key roles. The melanin content in the skin determines skin pigmentation. Abnormalities in skin pigmentation lead to various skin pigmentation disorders. Recent research has shown that the expression of EMP2 is much lower in melanoma than in normal melanocytes, but its role in melanogenesis has not yet been elucidated. Therefore, we investigated the role of EMP2 in the melanogenesis of MNT1 human melanoma cells. We examined TRP-1, TRP-2, and TYR expression levels during melanogenesis in MNT1 melanoma cells by gene silencing of EMP2. Western blot and RT-PCR results confirmed that the expression levels of TYR and TRP-2 were decreased when EMP2 expression was knocked down by EMP2 siRNA in MNT1 cells, and these changes were reversed when EMP2 was overexpressed. We verified the EMP2 gene was knocked out of the cell line (EMP2 CRISPR/Cas9) by using a CRISPR/Cas9 system and found that the expression levels of TRP-2 and TYR were significantly lower in the EMP2 CRISPR/Cas9 cell lines. Loss of EMP2 also reduced migration and invasion of MNT1 melanoma cells. In addition, the melanosome transfer from the melanocytes to keratinocytes in the EMP2 KO cells cocultured with keratinocytes was reduced compared to the cells in the control coculture group. In conclusion, these results suggest that EMP2 is involved in melanogenesis via the regulation of TRP-2 expression.
7.PRR16/Largen Induces Epithelial-Mesenchymal Transition through the Interaction with ABI2 Leading to the Activation of ABL1 Kinase
Gyeoung Jin KANG ; Jung Ho PARK ; Hyun Ji KIM ; Eun Ji KIM ; Boram KIM ; Hyun Jung BYUN ; Lu YU ; Tuan Minh NGUYEN ; Thi Ha NGUYEN ; Kyung Sung KIM ; Hiệu Phùng HUY ; Mostafizur RAHMAN ; Ye Hyeon KIM ; Ji Yun JANG ; Mi Kyung PARK ; Ho LEE ; Chang Ick CHOI ; Kyeong LEE ; Hyo Kyung HAN ; Jungsook CHO ; Seung Bae RHO ; Chang Hoon LEE
Biomolecules & Therapeutics 2022;30(4):340-347
Advanced or metastatic breast cancer affects multiple organs and is a leading cause of cancer-related death. Cancer metastasis is associated with epithelial-mesenchymal metastasis (EMT). However, the specific signals that induce and regulate EMT in carcinoma cells remain unclear. PRR16/Largen is a cell size regulator that is independent of mTOR and Hippo signalling pathways. However, little is known about the role PRR16 plays in the EMT process. We found that the expression of PRR16 was increased in mesenchymal breast cancer cell lines. PRR16 overexpression induced EMT in MCF7 breast cancer cells and enhances migration and invasion. To determine how PRR16 induces EMT, the binding proteins for PRR16 were screened, revealing that PRR16 binds to Abl interactor 2 (ABI2). We then investigated whether ABI2 is involved in EMT. Gene silencing of ABI2 induces EMT, leading to enhanced migration and invasion. ABI2 is a gene that codes for a protein that interacts with ABL proto-oncogene 1 (ABL1) kinase. Therefore, we investigated whether the change in ABI2 expression affected the activation of ABL1 kinase. The knockdown of ABI2 and PRR16 overexpression increased the phosphorylation of Y412 in ABL1 kinase. Our results suggest that PRR16 may be involved in EMT by binding to ABI2 and interfering with its inhibition of ABL1 kinase. This indicates that ABL1 kinase inhibitors may be potential therapeutic agents for the treatment of PRR16-related breast cancer.