Understanding of Epigenetic Regulations in Alzheimer’s Disease

Hyemyung SEO 한국생물공학회 2015 한국생물공학회 학술대회 Vol.2015 No.10

The hAPP-YAC transgenic model has elevated UPS activity in the frontal cortex similar to Alzheimer’s disease and Down’s syndrome

Seo, Hyemyung,Isacson, Ole Blackwell Publishing Ltd 2010 Journal of Neurochemistry Vol.114 No.6

<P><I>J. Neurochem.</I> (2010) <B>114</B>, 1819–1826.</P><P>Abstract</P><P>The ubiquitin-proteasome system (UPS) is critical for handling the intra-cellular load of abnormal and misfolded proteins in several neurodegenerative diseases. First, to determine the effects of the over-expression of human amyloid precursor protein (hAPP) on UPS, we measured proteasome activities using fluorescent substrates in the frontal cortex of hAPP-yeast artificial chromosome (YAC) transgenic (tg) mice (R1.40, hemizygous; Lamb, <I>Nat Genet</I>, <B>9</B>, 4; 1995). Chymotrypsin and PGPH-like activities of proteasome were increased in frontal cortex of hAPP-YAC tg mice. These proteasome activities (both chymotrypsin and PGPH-like) were further increased by cholinergic stimulation in littermate control mice, but not in hAPP-YAC tg mice. Nerve growth factor (NGF) levels were decreased by hAPP over-expression in the frontal cortex and hippocampus of hAPP-YAC tg mice, and further decreased by M1 agonist treatment in the hippocampus of littermate control and hAPP-YAC tg mice. Interestingly, the frontal cortex (BA9 area) of Alzheimer’s disease (AD) patients (Stage 3, <I>n</I> = 11) and Down’s syndrome (DS) patients (<I>n </I>= 9) showed similar up-regulation of the UPS activities to those seen in hAPP-YAC tg mice. M1 agonist stimulation increased the activities of &agr;-secretase, which were down-regulated by hAPP over-expression in the frontal cortex of hAPP-YAC tg mice. These results demonstrate that (i) hAPP-YAC tg mice have an up-regulation in the frontal cortex of the UPS similar to AD and DS patients; (ii) muscarinic stimulation increase UPS activities, increase secreted APP (APPs) levels, and decrease amyloid beta 42/40 ratio only in littermate controls, but not in hAPP-YAC tg mice. Taken together, these results suggest that both the adaptive reactions in the proteostatic network and pathological changes in AD and DS need to be considered in the future potential therapeutics.</P>

성인 쥐 뇌의 여러 영역에서의 콜린성 신경세포 특이적 유전자 발현의 정량

김우리,서혜명 한양대학교 이학기술연구소 2007 이학기술논문지 Vol.10 No.-

콜린성 신경세포는 신경계에 널리 분포하며, 대뇌피질 발달, 피질 활성, 대뇌 혈류 조절 및 인식, 학습, 기억 등의 조절에 중요한 역할을 하는 것으로 알려져 왔다. 본 연구에서는, 콜린성 신경세포가 주요하게 분포한다고 알려진 medial septum, frontal cortex, entorhinal cortex 및 whole brain 등의 성인 쥐 뇌의 여러 영역에서 M1 수용체 (M1 receptor, M1), 아세틸콜린 에스터레이즈 (acettylcholinesterase, AChE), 갈라닌 (galanin), 갈라닌 수용체 1 (galanin receptor 1, Galr1) 등의 콜린성 신경세포 특이적 유전자에 대한 발현정도의 차이를 RT-PCR을 통해 확인하고자 하였다. 그 결과, 같은 콜린 특이적 영역이라고 할지라도, 뇌의 각 영역 당 주요하게 발현되는 콜린성 신경세포 특이적 유전자의 발현 및 그 정도가 다르다는 것을 확인할 수 있었으며, 이러한 결과는 동일한 신경전달물질을 사용하는 뇌의 영역들이, 관련 유전자의 발현 차이를 통하여 각각의 주요 역할을 조절하여 수행할 수 있음을 시사한다. Cholinergic neuron, which uses acetylcholine as a neurotransmitter, is known to have a critical role in cerebral cortical development, cortical activity, controlling of cerebral blood flow, modulating of cognitive function, and learning and memory processes. In this study, we demonstrated the differences of expression levels of cholinergic neuron specific genes, such as M1 receptor (M1), acetylcholinesterase (AChE), galanin, and galanin receptor 1(Galrl), in the several cholinergic brain regions including medial septum, frontal cortex, entorhinal cortex and whole brain. Using semi-quantative RT-PCR for adult mice brain tissues, we founded that different cholinergic brain regions show different expression patterns of specific cholinergic genes. These results indicate that cholinergic neurons in specific brain regions may regulate their major functions, as shown in the expression profiles of cholinergic specific genes.

헌팅턴씨 병 세포 모델에서 돌연병이 헌팅틴이 유비퀴틴-프로테아좀 시스템의 기능 및 세포 생존력에 미치는 영향

김우리,서혜명 한양대학교 이학기술연구소 2006 이학기술논문지 Vol.9 No.-

가바성 신경세포는 헌팅턴씨 병 (Huntington's disease: HD) 환자의 특정 뇌 영역에서 선택적 취약성을 나타내며, 유비퀴틴-프로테아좀 시스템 (ubiquitin-proteasome system: UPS) 은 이러한 특정 신경의 퇴행에 있어서 비정상적인 단백질의 응축과 연관되어 있는 것으로 알려져 왔다. 본 연구에서는, 가바성 ST14A 세포에 돌연변이된 헌팅틴 유전자가 과발현 되었을 때 UPS 기능 및 세포 생존력에 어떤 영향을 미치는지를 확인하고자 하였다. 이를 위해 돌연변이 헌팅틴 유진자의 과발현이 유도된 ST14A 세포를 이용하여, 미토콘드리아의 효소 활성 저해제인 3-NP를 처리하였을 때 세포 생존력과 프로테아좀 활성이 감소되었으며, 이러한 프로테아좀 활성의 감소는 프로테아좀 활성인자인 PA28α나 β의 렌티바이러스를 통한 유전자 전이를 통해 복구될 수 있었다. 본 연구의 결과를 통하여 프로테아좀 활성의 변형이 UPS 및 가바성 신경세포의 세포 생존 관련 기작을 변형시킬 수 있으며, 나아가 HD의 잠재적인 치료의 표적이 될 수 있음을 시사한다. GABAergic neurons are selectively vulnerable m the several brain regions of Huntington's disease (HD) Patients. Ubiquitin-proteasome system (UPS) has been reported to be related to abnormal protein aggregation in the neurodegenerative diseases. To understand the mechanism of UPS function in HD, we used in vitro HD model system such as GABAergic ST14A cells. We administered mitochondrial enzyme inhibitor, 3-NP, which causes energy impairment and replicates most of pathophysiological features of HD, into these neurons. The cell viabilities and chymotrypsin-like proteasome activities were determined using LDH assay and fluorescence substrate-based enzyme activity assay. HD cell with mutant huntingtin induction showed the decreased cell survival against 3-NP toxicity. These HD cells also showed decreased proteasome activities which further increased by overexpression of PA28α or P. These results indicate the modification of proteasome accivity can alter the UPS function and other cellular survival mechanisms of GABAergic neurons in HD pathology.

Increased DJ-1 in Urine Exosome of Korean Males with Parkinson's Disease

Ho, Dong Hwan,Yi, Sanghak,Seo, Hyemyung,Son, Ilhong,Seol, Wongi Hindawi Publishing Corporation 2014 BioMed research international Vol.2014 No.-

<P>Parkinson's disease (PD) is a difficult disease to diagnose although it is the second most common neurodegenerative disease. Recent studies show that exosome isolated from urine contains LRRK2 or DJ-1, proteins whose mutations cause PD. To investigate a potential use for urine exosomes as a tool for PD diagnosis, we compared levels of LRRK2, <I>α</I>-synuclein, and DJ-1 in urine exosomes isolated from Korean PD patients and non-PD controls. LRRK2 and DJ-1, but not <I>α</I>-synuclein, were detected in the urine exosome samples, as reported previously. We initially could not detect any significant difference in these protein levels between the patient and the control groups. However, when age, disease duration, L-dopa daily dose, and gender were considered as analytical parameters, LRRK2 and DJ-1 protein levels showed clear gender-dependent differences. In addition, DJ-1 level was significantly higher (1.7-fold) in male patients with PD than that in male non-PD controls and increased in an age-dependent manner in male patients with PD. Our observation might provide a clue to lead to a novel biomarker for PD diagnosis, at least in males.</P>

EPITRANS: A database that integrates epigenome and transcriptome data

Cho, Soo Young,Chai, Jin Choul,Park, Soo Jun,Seo, Hyemyung,Sohn, Chae-Bong,Lee, Young Seek Springer-Verlag 2013 Molecules and cells Vol.36 No.5

Suppression of neuroinflammation by matrix metalloproteinase-8 inhibitor in aged normal and LRRK2 G2019S Parkinson's disease model mice challenged with lipopolysaccharide

Kim, Jisun,Jeong, Yeon-Hui,Lee, Eun-Jung,Park, Jin-Sun,Seo, Hyemyung,Kim, Hee-Sun Elsevier 2017 Biochemical and biophysical research communication Vol. No.

<P><B>Abstract</B></P> <P>Microglial priming is caused by aging and neurodegenerative diseases, and is characterized by an exaggerated microglial inflammatory response to secondary and sub-threshold challenges. In the present study, we examined the effects of the matrix metalloproteinase-8 (MMP-8) inhibitor (M8I) on the brain of aged normal and leucine-rich repeat kinase 2 (LRRK2) G2019S Parkinson's disease (PD) model mice systemically stimulated with lipopolysaccharide (LPS). The results indicated that Iba-1 positive microglia and GFAP-positive astrocytes, which were increased by LPS, significantly decreased by M8I in aged normal and PD model mice. M8I also decreased the expression of pro-inflammatory markers in the hippocampus and midbrain of aged normal and PD model mice challenged with LPS, while it also improved the motor coordination of aged normal mice after LPS challenge in rotor rod test and the general crossing locomotor activities of LPS-treated LRRK2G2019S PD mice after LPS challenge in open field test. To assess the effects of M8I in an <I>in vitro</I> priming model, BV2 microglia were pretreated with macrophage colony-stimulating factor (CSF)-1 or interleukin (IL)-34, and subsequently stimulated with LPS or polyinosinic-polycytidylic acid (poly[I:C]). M8I inhibited the LPS- or poly(I:C)-induced production of the tumor necrosis factor-α and nitric oxide, alone or in combination with CSF-1 or IL-34. Collectively, the data suggested that M8I has a therapeutic potential in treating neurodegenerative diseases that are aggravated by systemic inflammation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> M8I decreased glial activation in aged normal and PD mice challenged with LPS. </LI> <LI> M8I suppressed LPS-induced neuroinflammation in aged normal and PD mice. </LI> <LI> M8I ameliorated LPS-induced behavioral deficits in aged normal and PD mice. </LI> <LI> M8I also showed anti-inflammatory effects in an <I>in vitro</I> priming model. </LI> </UL> </P>

구조적 이상 현상을 위한 FOL 기반의 비즈니스 프로세스 검증

김건우(Gun-Woo Kim),이승훈(Seung Hoon Lee),서혜명(Hyemyung Seo),손진현(Jin Hyun Son) 한국정보과학회 2009 한국정보과학회 학술발표논문집 Vol.36 No.2A

G2385R and I2020T Mutations Increase LRRK2 GTPase Activity

Ho, Dong Hwan,Jang, Jihoon,Joe, Eun-hye,Son, Ilhong,Seo, Hyemyung,Seol, Wongi Hindawi Publishing Corporation 2016 BioMed research international Vol.2016 No.-

<P>The LRRK2 mutation is a major causal mutation in familial Parkinson's disease. Although LRRK2 contains functional GTPase and kinase domains and their activities are altered by pathogenic mutations, most studies focused on LRRK2 kinase activity because the most prevalent mutant, G2019S, enhances kinase activity. However, the G2019S mutation is extremely rare in the Asian population. Instead, the G2385R mutation was reported as a major risk factor in the Asian population. Similar to other LRRK2 studies, G2385R studies have also focused on kinase activity. Here, we investigated GTPase activities of G2385R with other LRRK2 mutants, such as G2019S, R1441C, and I2020T, as well as wild type (WT). Our results suggest that both I2020T and G2385R contain GTPase activities stronger than that of WT. A kinase assay using the commercial recombinant proteins showed that I2020T harbored stronger activity, whereas G2385R had weaker activity than that of WT, as reported previously. This is the first report of LRRK2 I2020T and G2385R GTPase activities and shows that most of the LRRK2 mutations that are pathogenic or a risk factor altered either kinase or GTPase activity, suggesting that their physiological consequences are caused by altered enzyme activities.</P>

Oxidized DJ-1 Levels in Urine Samples as a Putative Biomarker for Parkinson's Disease

Jang, Jihoon,Jeong, Soyeon,Lee, Sung Ik,Seol, Wongi,Seo, Hyemyung,Son, Ilhong,Ho, Dong Hwan Hindawi 2018 Parkinson’s disease Vol.2018 No.-

<P>Parkinson's disease (PD) is the second most common neurodegenerative disease. Oxidative stress is the most critical risk factor for neurodegenerative diseases, including Alzheimer's disease (AD) and Huntington's disease (HD). Numerous reports have demonstrated that oxidative stress aggravates cytotoxicity in dopaminergic neurons and accelerates the formation of protein inclusions. In addition, oxidative stress, such as 4-hydroxynonenal (HNE), oxidized protein, and dopamine quinone, are related to PD progression. <I>DJ-1</I> is a PD-causative gene, and it plays a pivotal role as a sensor and eliminator of oxidative stress. Several studies have shown that oxidized DJ-1 (OxiDJ-1) formation is induced by oxidative stress. Hence, previous studies suggest that oxidized DJ-1 could be a biomarker for PD. We previously reported higher DJ-1 levels in Korean male PD patient urine exosomes than male non-PD controls. We speculate that OxiDJ-1 levels in PD patient urine might be higher than that in non-PD controls. In this study, we established an ELISA for OxiDJ-1 using recombinant DJ-1 treated with H<SUB>2</SUB>O<SUB>2</SUB>. Using Western blot assay and ELISA, we confirmed an increase of OxiDJ-1 from HEK293T cells treated with H<SUB>2</SUB>O<SUB>2</SUB>. Using our ELISA, we observed significantly higher, 2-fold, OxiDJ-1 levels in the urine of Korean PD patients than in non-PD controls.</P>