• BMB Reports
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• v.51 no.1
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• pp.5-13
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• 2018

Formation of toxic protein aggregates is a common feature and mainly contributes to the pathogenesis of neurodegenerative diseases (NDDs), which include amyotrophic lateral sclerosis (ALS), Alzheimer's, Parkinson's, Huntington's, and prion diseases. The transglutaminase 2 (TG2) gene encodes a multifunctional enzyme, displaying four types of activity, such as transamidation, GTPase, protein disulfide isomerase, and protein kinase activities. Many studies demonstrated that the calcium-dependent transamidation activity of TG2 affects the formation of insoluble and toxic amyloid aggregates that mainly consisted of NDD-related proteins. So far, many important and NDD-related substrates of TG2 have been identified, including $amlyoid-{\beta}$, tau, ${\alpha}-synuclein$, mutant huntingtin, and ALS-linked trans-activation response (TAR) DNA-binding protein 43. Recently, the formation of toxic inclusions mediated by several TG2 substrates were efficiently inhibited by TG2 inhibitors. Therefore, the development of highly specific TG2 inhibitors would be an important tool in alleviating the progression of TG2-related brain disorders. In this review, the authors discuss recent advances in TG2 biochemistry, several mechanisms of molecular regulation and pleotropic signaling functions, and the presumed role of TG2 in the progression of many NDDs.

• Journal of Haehwa Medicine
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• v.12 no.1
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• pp.11-26
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• 2003

Alzheimer's disease (AD) is characterized by amyloid deposition and associated loss of neunons in brain regions involved in learning and memory processes. Several causes of evidence support that the congnitive disturbance is closed associated with the deficit of cerebral acetylcholine neurotransmission, and the effect of carboxyl terminal 105 amino acid fragment (CT105) of the amyloid precursor protein (APP) on the gene expression of proinflammatory cytokines. We tested it on the scopolamine-induced amnesia model of the ICR mouse using the Morris water maze with repeated orally administration of 1st Green-Tea extract (200 mg/kg) and 2nd Green-Tea extract (200 mg/kg). The Green-Tea prevents impairment of learning and memory and neuronal loss in mouse models of cognitive disturbance and it demonstrated selectivity for inhibition of acetylcholinesterase (AChE). Furthermore, the repeated administration of Green-Tea, CT105-induced alzheimer's mouse model showed central cholinergic activity by ameliorates learning and memory impairment, and isolation of CD14 microglia showed significantly decreases intracellular release of the proinflammatory cytokines tumor necrosis factor-${\alpha}$, interleukin-$1{\beta}$ and reactive oxygen species (ROS). Because of its composite profile, oral therapeutic index and a prophylactic, Green-Tea is considered the better therapeutic candidate for the treatment of Alzheimer's disease.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.47-47
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• 2003

The presenilin 1 (PS1) or PS2 is an essential component of the ${\gamma}$-secretase complex, which mediates the intramembrane proteolysis of selected type-I membrane, including the ${\beta}$-amyloid precursor protein (APP) to yield A${\beta}$. Familial Alzheimer's disease (FAD)-associated mutations in presenilins give rise to an increased production of a highly amyloidogenic A${\beta}$42. In addition to their well-documented proteolytic function, the presenilins play a role in calcium signaling. We have previously reported that presenilin FAD mutations cause highly consistent alterations in intracellular calcium signaling pathways, which include deficits in capacitative calcium entry (CCE), the refilling mechanism for depleted internal calcium stores. However, molecular basis for the presenilin-mediated modulation of CCE remains to be elucidated. In the present study, whole-cell patch clamp method was used to identify a specific calcium-permeable ion channel current(s) that is responsible for the CCE deficits associated with FAD-linked PS1 mutants. Unexpectedly, both voltage-activated and conventional store depletion-activated calcium currents I(CRAC), were absent in HEK293 cells, which were stably transfected either with wild-type or FAD mutant (L286V, M146L, and delta E9) forms of PS1. Recently, magnesium-nucleotide-regulated metal cation current, or I(MagNum), has been described and appears to share many common properties with I(CRAC) including calcium permeability and inhibitor sensitivity (e.g. 2-APB). We have detected I(MagNum) in all 293 cells tested. Interestingly, FAD mutant 293 cells developed only about half of currents compared to PS1 wild type cells.

• Molecules and Cells
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• v.21 no.2
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• pp.244-250
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• 2006

Gangliosides are receptors for various peptides and proteins including neuropeptides, ${\beta}$-amyloid proteins, and prions. Recently, the role of gangliosides in mucosal immunization has attracted attention due to the emerging interest in oral vaccination. Ganglioside GM1 exists in abundance on the surface of the M cells of Peyer's patch, a well-known mucosal immunity induction site. In the present study we identified a peptide ligand for GM1 and tested whether it played a role in immune induction. GM1-binding peptides were selected from a phage-displayed dodecapeptide library and one peptide motif, GWKERLSSWNRF, was fused to the C-terminus of enhanced green fluorescent protein (EGFP). The fusion protein, but not EGFP fused with a control peptide, was concentrated around Peyer's patch after incubation in the lumen of the intestine ex vivo. Furthermore, oral feeding of the fusion protein but not control EGFP induced mucosal and systemic immune responses against EGFP resembling Th2-type immune responses.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.132.1-132.1
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• 2003

Biphenyl dimethyl dicarboxylate (DDB) is a by-product produced in process of synthesizing Schizandrin-C. Generally, DDB has known to protect hepatocytes and to decrease the index of liver enzyme (e.g. GOT and GPT) in chronic hepatitis. The present study was aimed to demonstrate whether DDB can protect the brain cell, especially the Alzheimer brain in vitro. As Alzheimers disease can be induced by activated microglia, a macrophage in the brain, through Abeta peptide (A$\beta$) produced from amyloid precursor protein (APP). (omitted)

• YAKHAK HOEJI
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• v.49 no.1
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• pp.103-108
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• 2005

Tacrine analogues for degenerative brain disease treatments have been designed. A series of diazaanthrine derivatives as novel analogues of tacrine has been prepared through the alkyl substitution and the ring expansion. They were expected to retain anti-inflammatory activity by inhibition of prostaglandin production with reduction of side effect as the selective prostaglandin synthase inhibitor. Prostaglandin synthase expression is associated with the deposition of beta-amyloid protein in neuritic plaques in brain inflammation. Therefore selective prostaglandin synthase blockade is important for the prevention and treatment of alzheimer's disease. To evaluate inhibitory effect of prostaglandin synthase, synthetic tacrine derivatives were screened with accumulation of prostaglandin biosynthesis by lipopolysaccharide in aspirin-treated murine macrophage cell. Most of synthetic compounds have shown significant prostaglandin synthase activities in vitro screening with $84.3{\sim}33.6\%$ inhibition of the prostaglandin $E_2$ production at $10\;{\mu}g/ml$.

• Biomolecules & Therapeutics
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• v.26 no.4
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• pp.350-357
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• 2018

Glial cells are receiving much attention since they have been recognized as important regulators of many aspects of brain function and disease. Recent evidence has revealed that two different glial cells, astrocytes and microglia, control synapse elimination under normal and pathological conditions via phagocytosis. Astrocytes use the MEGF10 and MERTK phagocytic pathways, and microglia use the classical complement pathway to recognize and eliminate unwanted synapses. Notably, glial phagocytosis also contributes to the clearance of disease-specific protein aggregates, such as ${\beta}$-amyloid, huntingtin, and ${\alpha}$-synuclein. Here we reivew recent findings showing that glial cells are active regulators in brain functions through phagocytosis and that changes in glial phagocytosis contribute to the pathogenesis of various neurodegenerative diseases. A better understanding of the cellular and molecular mechanisms of glial phagocytosis in healthy and diseased brains will greatly improve our current approach in treating these diseases.

• Journal of Pharmacopuncture
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• v.9 no.2
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• pp.17-37
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• 2006

Objectives : To observe the changes in the serum proteins after intravenous injection of cultivated wild ginseng pharmacopuncture. Methods : Blood was collected before and after the administration of cultivated wild ginseng pharmacopuncture and only the serum was taken. Then differences in the spots on the scanned image after carrying out 2-Dimensional electrophoresis were located and conducted mass analysis and protein identification. Results : Following results were obtained from the comparative analysis of serum proteins before and after the administration of cultivated wild ginseng pharmacopuncture. 1. 28 spots were identified before and after the administration. 2. In confirming manifestation degree, spots with more than two-times increase were 204, 1302, 2205, 3105, 7104, 8006, spots with more than one-time increase were 1101, 1505, 2013, 2403, 3009, 3010, 4002, 4009, 6704, 8101, and spots with decrease were 205, 801, 803, 3205, 5202, 6105, 6106, 7103, 9001, 9003. 3. After conducting protein identification, proteins 205, 804, 1302, 4009, 6105, 6106 are unidentified yet, and 1l01 is unnamed protein. Protein 204 is identified as complement receptor CR2-C3d, 801 as YAPl protein, 803 as antitrypsin polymer, 1505 as PRO0684, 2013 and 3010 as proapolipoprotein, 2205 as USP48, 2403 as vitamin D binding protein, 3009 as complement component 4A preprotein, 3105 as immunoglobulin lambda chain, 3205 as transthyretin, 4002 as Ras-related protein Ral-A, 4204 as beta actin, 5202 and 7104 as apolipoprotein Ll, 6704 as alpha 2 macroglobulin precursor, 7103 as complement component 3 precursor, 8006 as testis-specific protein Y, 8101 as transferrin, 9001 as (Alpha-Oxy, Beta-(Cl12g)deoxy) T-State Human Hemoglobin, and 9003 as human hemoglobin. 4. Immune protein CR2-C3d(204), which acts against microbes and pathogenic organisms, was increased by more than two-times after the administration of pharmacopuncture. 5. Antitrypsin(803), which is secreted with inflammatory response in the lungs, was reduced after the administration of pharmacopuncture. 6. Proapolipoprotein(2013, 3010) and apolipoprotein(7104), key components of the HDL-cholesterol which plays an important role in preventing arteriosclerosis, were increased after the administration of pharmacopuncture. 7. Vitamin D binding protein(DBP, 2403), protecting the lung at the time of inflammatory response, was increased after the administration of pharmacopuncture. 8. Transthyretin(TTR, 3205), which is the main protein causing familial amyloid polyneuropathy(FAP), was decreased after the administration of pharmacopuncture. 9. Ras-related protein Ral-A(4002) that controls phospholipid metabolism, cytoskeletal formation, and membrane traffic, was increased after the administration of pharmacopuncture. 10. Testis-specific protein Y(8006), which takes part in determination of the gender, was increased by more than two-times after the administration of pharmacopuncture. 11. Transferrin(8101), which balances the iron level in the body, was increased after the administration of pharmacopuncture. Conclusion : Above results support the notion that intravenous injection of cultivated wild ginseng pharmacopuncture induce changes in serum proteins and this research can be a pioneer work in finding biomarkers.

• Yonsei Medical Journal
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• v.59 no.9
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• pp.1096-1106
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• 2018

Purpose: Alzheimer's disease (AD) is the sixth most common cause of death in the United States. MicroRNAs have been identified as vital players in neurodegenerative diseases, including AD. microRNA-128 (miR-128) has been shown to be dysregulated in AD. This study aimed to explore the roles and molecular mechanisms of miR-128 in AD progression. Materials and Methods: Expression patterns of miR-128 and peroxisome proliferator-activated receptor gamma ($PPAR-{\gamma}$) messenger RNA in clinical samples and cells were measured using RT-qPCR assay. $PPAR-{\gamma}$ protein levels were determined by Western blot assay. Cell viability was determined by MTT assay. Cell apoptotic rate was detected by flow cytometry via double-staining of Annexin V-FITC/PI. Caspase 3 and $NF-{\kappa}B$ activity was determined by a Caspase 3 Activity Assay Kit or $NF-{\kappa}B$ p65 Transcription Factor Assay Kit, respectively. Bioinformatics prediction and luciferase reporter assay were used to investigate interactions between miR-128 and $PPAR-{\gamma}$ 3'UTR. Results: MiR-128 expression was upregulated and $PPAR-{\gamma}$ expression was downregulated in plasma from AD patients and $amyloid-{\beta}$ $(A{\beta})-treated$ primary mouse cortical neurons (MCN) and Neuro2a (N2a) cells. Inhibition of miR-128 decreased $A{\beta}-mediated$ cytotoxicity through inactivation of $NF-{\kappa}B$ in MCN and N2a cells. Moreover, $PPAR-{\gamma}$ was a target of miR-128. $PPAR-{\gamma}$ upregulation attenuated $A{\beta}-mediated$ cytotoxicity by inactivating $NF-{\kappa}B$ in MCN and N2a cells. Furthermore, $PPAR-{\gamma}$ downregulation was able to abolish the effect of anti-miR-128 on cytotoxicity and $NF-{\kappa}B$ activity in MCN and N2a cells. Conclusion: MiR-128 inhibitor decreased $A{\beta}-mediated$ cytotoxicity by upregulating $PPAR-{\gamma}$ via inactivation of $NF-{\kappa}B$ in MCN and N2a cells, providing a new potential target in AD treatment.

• Korean Journal of Medicinal Crop Science
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• v.28 no.2
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• pp.85-94
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• 2020

Background: Alzheimer's disease (AD) is caused by various factors, such as cholinergic dysfunction, regulation of neurotrophic factor expression, and accumulation of amyloid-beta. We investigated whether or not a combination of Carthamus tinctorius L. seed and Taraxacum coreanum (CT) has a protective effect on scopolamine-induced memory impairment in a mouse model. Methods and Results: Mice were orally pretreated with CT (50, 100 and 200 mg/kg/day) for 14 days, and scopolamine (1 mg/kg/day) was injected intraperitoneally before subjecting them to behavior tests. CT-administered mice showed better novel object recognition and working memory ability than scopolamine-treated control mice. In T-maze and Morris water maze tests, CT (100 and 200 mg/kg/day) significantly increased space perceptive ability and occupancy to the target quadrant, respectively. In addition, 100 and 200 mg/kg/day of CT attenuated cholinergic dysfunction through inhibition of butyryl cholinesterase in brain tissue. Furthermore, CT-administered mice showed higher cyclic adenosine monophosphate-response element-binding protein (CREB) levels and lower amyloid precursor protein (APP) levels compared to scopolamine-treated control mice. Conclusions: CT improved scopolamine-induced memory impairment through inhibition of cholinergic dysfunction, up-regulation of CREB, and down-regulation of APP. Therefore, CT could be a useful therapeutic agent for AD with protective effects on cognitive impairment.