• Journal of the Korean Magnetic Resonance Society
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• v.2 no.2
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• pp.85-105
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• 1998

Prions cause neurodegenerative diseases in animals and humans. The scrapie prion protein (PrPSc) is the major-possibly only-component of the infectious prion and is generated from the cellular isoform (PrPC) by a conformational change. Limited proteolysis of PrPSc produces an polypeptide comprised primarily of residues 90 to 231, which retains infectivity. The three-dimensional structure of rPrP(90-231), a recombinant protein resembling PrPC with the Syrian hamster (SHa) sequence, was solved using multidimensional NMR. Low-resolution structures of rPrP(90-231), synthetic peptides up to 56 residues, a longer (29-231, full-length) protein with SHa sequence, and a short here further structure refinement of rPrP(90-231) and dynamic features of the protein. Consideration of these features in the context of published data suggests regions of conformational heterogeneity, structural elements involved in the PrPC\longrightarrowPrPSc transformation, and possible structural features related to a species barrier to transmission of prion diseases.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.73-76
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• 2006

Neuronal precursor cells may provide for cell replacement or gene delivery vehicles in neurodegenerative disease therapy. One impediment to treating neuronal diseases is finding ways to introduce genes into neurons effectively. It is shown here that fiber-modified adenovirus vector delivered gene to neuronal precursor as well as differentiated neuronal cells more efficiently than first-generation adenoviral vector. Moreover, fiber-modified adenoviral vector transduced precursor cells retained the potential for differentiation into neurons and glia in vitro. These results show the potential of modified adenoviral vector in the improved gene delivery to neurons in direct gene therapy protocols. In addition it holds promise for the use of genetically manipulated stem cells for the therapy of neuronal diseases.

• BMB Reports
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• v.53 no.10
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• pp.491-499
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• 2020

The extracellular matrix is a critical component of every human tissue. ECM not only functions as a structural component but also regulates a variety of cellular processes such as cell migration, differentiation, proliferation, and cell death. In addition, current studies suggest that ECM is critical for the pathophysiology of various human diseases. ECM is composed of diverse components including several proteins and polysaccharide chains such as chondroitin sulfate, heparan sulfate, and hyaluronic acid. Each component of ECM exerts its own functions in cellular and pathophysiological processes. One of the interesting recent findings is that ECM is involved in inflammatory responses in various human tissues. In this review, we summarized the known functions of ECM in neuroinflammation after acute injury and chronic inflammatory diseases of the central nerve systems.

• Molecules and Cells
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• v.42 no.12
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• pp.821-827
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• 2019

Aging is the most important single risk factor for many chronic diseases such as cancer, metabolic syndrome, and neurodegenerative disorders. Targeting aging itself might, therefore, be a better strategy than targeting each chronic disease individually for enhancing human health. Although much should be achieved for completely understanding the biological basis of aging, cellular senescence is now believed to mainly contribute to organismal aging via two independent, yet not mutually exclusive mechanisms: on the one hand, senescence of stem cells leads to exhaustion of stem cells and thus decreases tissue regeneration. On the other hand, senescent cells secrete many proinflammatory cytokines, chemokines, growth factors, and proteases, collectively termed as the senescence-associated secretory phenotype (SASP), which causes chronic inflammation and tissue dysfunction. Much effort has been recently made to therapeutically target detrimental effects of cellular senescence including selectively eliminating senescent cells (senolytics) and modulating a proinflammatory senescent secretome (senostatics). Here, we discuss current progress and limitations in understanding molecular mechanisms of senolytics and senostatics and therapeutic strategies for applying them. Furthermore, we propose how these novel interventions for aging treatment could be improved, based on lessons learned from cancer treatment.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.127-127
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• 1998

Specific inhibitors of a calcium activated neutral protease calpain could be used for the treatment of neurodegenerative diseases, cataract and muscular dystrophy diseases because of their therapeutic effects. In the course of screening for potential calpain inhibitors from microorganisms, a new analogue of chymostatins named calmostinol was isolated from the culture filtrate of an actinomycete. The MW was determined to be 596 [(M + H)$\^$+/] by FAB-MS in glycerol matrix. The structure was elucidated to be N-[((S)-1-carboxy-2-phenylethyl)-carbamoyl]-${\alpha}$-[2- iminohexahydro-4(S)-pyrimidyl]-L-glycyl- L-valyl-phenylalaninol, by the spectroscopic methods such as NMR and MS fragmentation studies. Calmostinol exhibited strong activity against calpain while not against a Ca$\^$2+/ -independent cysteine protease papain.

• Molecules and Cells
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• v.39 no.9
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• pp.680-686
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• 2016

Uncoupling proteins (UCPs) are mitochondrial inner membrane proteins that function to dissipate proton motive force and mitochondrial membrane potential. One UCP has been identified in Caenorhabditis elegans (C. elegans), namely UCP-4. In this study, we examined its expression and localization using a GFP marker in C. elegans. ucp-4 was expressed throughout the body from early embryo to aged adult and UCP-4 was localized in the mitochondria. It is known that increased mitochondrial membrane protential leads to a reactive oxygen species (ROS) increase, which is associated with age-related diseases, including neurodegenerative diseases in humans. A ucp-4 mutant showed increased mitochondrial membrane protential in association with increased neuronal defects during aging, and the neurons of ucp-4 overexpressing animals showed decreased neuronal defects during aging. These results suggest that UCP-4 may be involved in neuroprotection during aging via relieving mitochondrial membrane protential. We also investigated the relationship between UCP-4 and innate immunity because increased ROS can affect innate immunity. ucp-4 mutant displayed increased resistance to the pathogen Staphylococcus aureus compared to wild type. The enhanced immunity in the ucp-4 mutant could be related to increased mitochondrial membrane protential, presumably followed by increased ROS. In summary, UCP-4 might have an important role in neuronal aging and innate immune responses through mediating mitochondrial membrane protential.

• Molecules and Cells
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• v.22 no.2
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• pp.198-202
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• 2006

The $P2X_7$ receptor, an ATP-gated cation channel, induces cell death in immune cells and is involved in neurodegenerative diseases. Although the receptor plays various roles in these diseases, the cellular mechanisms involved are poorly understood and antagonists are limited. Here, the development of a cell-based assay for human $P2X_7$ receptor is reported. We established permanent lines of HEK 293 cells expressing a high level of $hP2X_7$ receptor. Functional activity of the $hP2X_7$ receptor was confirmed by whole-cell patch recording of ATP-induced ion currents. Prolonged exposure to ATP resulted in death of the $hP2X_7$-expressing HEK 293 cells and this cell death could be quantified. Two known $P2X_7$ antagonists, PPADS and KN-62, blocked ATP-induced death in a concentration-dependent manner. Thus, this assay can be used to screen for new antagonists of $hP2X_7$ receptors.

• Journal of Ginseng Research
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• v.31 no.3
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• pp.117-126
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• 2007

Ginseng, the root of Panax species, a well-known herbal medicine has been used as a traditional medicine for thousands of years and is now a popular and worldwide used natural medicine. Ginseng has been used primarily as a tonic to invigorate weak bodies to help the restoration of homeostasis in a wide range of pathological conditions such as cardiovascular diseases, cancer, immune deficiency and hepatotoxicity. Although conclusive clinical data in humans is still missing, recent research results have suggested that some of the active ingredients ginseng exert beneficial effects on central nervous system (CNS) disorders and neurodegenerative diseases, suggesting it could be used in treatment of psychotic disorders. Data from neural cell cultures and animal studies contribute to the understanding of these mechanisms that involve inhibitory effects on stress-induced corticosterone level increasing and modulating of neurontransmitters, reducing $Ca^{2+}$ over-influx, scavenging of free radicals and counteracting excitotoxicity. In this review, we focused on recently reported medicinal effects of ginseng and summarized the possibility of its applications on psychotic disorders.

• Biomedical Science Letters
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• v.24 no.3
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• pp.168-174
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• 2018

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by abdominal pain, rectal bleeding and diarrhea. Gastrodia elata Blume (GE) has been used for the treatment of various diseases including neurodegenerative diseases and inflammatory disease. However, there has been no information on whether GE regulates intestinal inflammation. The aim of this study is to elucidate whether GE can protect against dextran sulfate sodium (DSS)-induced colitis in a mouse model. The colitis mice were induced by drinking water containing 5% DSS for 7 days. Body weight, colon length and clinical score were assessed to determine the effects on colitis. The levels of inflammatory cytokines, tumor necrosis factor $(TNF)-{\alpha}$ and interleukin (IL)-6 in colitis tissue were also measured. The results showed that mice administrated with DSS showed clinical signs including weight loss and reduced colon length. GE inhibited the DSS-induced loss of body weight and shortening of colon and increased Disease activity index score. Additionally, we observed that GE suppressed the levels of $TNF-{\alpha}$ and IL-6 in DSS-treated colon tissues. Collectively, these findings provide experimental evidence that GE might be a useful therapeutic agent for patients with UC.

• YAKHAK HOEJI
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• v.44 no.5
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• pp.448-454
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• 2000

Microglia, brain resident macrophages, play a central role in the inflammatory responses of the brain and are activated in brain injuries and several neurodegenerative diseases such as Alzheimer's and Parkinson's disease, thereby aggravating the course of these diseases. In this study, the effects of plantderived compounds such as curcumin or gingerol on the microglial activation were examined. Microglial cultures were prepared from 2~3 week mixed primary glial cultures obtained from the cerebral cortex of 1~2 day old rats and identified by immunocytochemistry using microglial-specific antibody OX-42. Microglia were activated by lipopolysaccharide (LPS) and interferon-${\gamma}$ (IFN-${\gamma}$) and the effect of curcumin or 6-gingerol on the microglial activation was examined. Specific parameters measured to monitor microglial activation were nitric oxide (NO), prostaglandin E$_2$(PGE$_2$) and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) release. Curcumin (1~10 $\mu$M) inhibited NO release induced by LPS and IFN-${\gamma}$ in a dose-dependent manner whereas 6-gingerol (2~20 $\mu$M) did not have any effect on LPS/IFN-${\gamma}$-induced NO release. The levels of PGE$_2$and TNF-$\alpha$ induced by LPS and IFN-${\gamma}$ were also inhibited by 1~10 $\mu$M curcumin in a dose-dependent manner. These results showed that curcumin could modulate microglial activation.