• Title/Summary/Keyword: Molecular mechanisms

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Anti-proliferative Activities of Solvent Fractions of Lees Extracts in Human Colorectal HCT116 Cells (대장암 세포주에서 주박 추출물의 유기용매 분획물의 항성장 활성)

  • Kang, Hyung-Taek;Lee, Seung Hoon;Kim, Soon Young;Kim, Mi-Sun;Shin, Woo-Chang;Sohn, Ho-Yong;Kim, Jong-Sik
    • Journal of Life Science
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    • v.24 no.9
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    • pp.967-972
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    • 2014
  • In the present study, we prepared eighty-five different kinds of lees extracts and their solvent fractions and investigated their anti-proliferative activities against human colorectal cancer HCT116 cells. HCT116 cells were treated with eighty-five solvent fractions of lees extracts and then cell viability was measured using MTS assay. Among the treated solvent fractions, three solvent fractions (KSD-E1-3, KSD-E2-3, and KSD-E4-3) were selected based on cell viability assay. In addition, we performed an oligo DNA microarray analysis to analyze the gene expression changes by treatment of KSD-E1-3 in HCT116 cells. Among the upregulated genes, we selected 4 genes (NAG-1, ATF3, p21, and DDIT3) and performed RT-PCR using gene-specific primers. Among the treated solvent fractions, KSD-E1-3 dramatically induced the expressions of the four selected genes. In addition, we investigated whether the upregulations of those genes were dependent on the transcription factor p53's presence using p53 null HCT116 cells. The results indicate that the upregulations of NAG-1, ATF3, and DDIT3 are not dependent on the p53 presence, whereas p21 is dependent on the p53 presence. These findings may help to understand the molecular mechanisms of the anti-proliferative activity mediated by rice wine lees in human colorectal cancer cells.

Cytoprotective Effects of Schisandrin A against Hydrogen Peroxide-induced Oxidative Stress in SW1353 Human Chondrocytes (SW1353 인간 연골세포에서 산화적 스트레스에 대한 schisandrin A의 세포 보호 효과)

  • Jeong, Jin-Woo;Choi, Eun Ok;Kwon, Da Hye;Kim, Bum Hoi;Park, Dong Il;Hwang, Hye Jin;Kim, Byung Woo;Choi, Yung Hyun
    • Journal of Life Science
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    • v.27 no.9
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    • pp.1070-1077
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    • 2017
  • Chondrocyte apoptosis induced by reactive oxygen species (ROS) plays an important role in the pathogenesis of osteoarthritis. Schisandrin A, a bioactive compound found in fruits of the Schisandra genus, has been reported to possess multiple pharmacological and therapeutic properties. Although several studies have described the antioxidant effects of analogues of schisandrin A, the underlying molecular mechanisms of this bioactive compound remain largely unresolved. The present study investigated the cytoprotective effect of schisandrin A against oxidative stress (hydrogen peroxide [$H_2O_2$]) in SW1353 human chondrocyte cells. The results showed that schisandrin A preconditioning significantly inhibited $H_2O_2-induced$ growth inhibition and apoptotic cell death by blocking the degradation of poly (ADP-ribose) polymerase proteins and down-regulating pro-caspase-3. These antiapoptotic effects of schisandrin A were associated with attenuation of mitochondrial dysfunction and normalization of expression changes of proapoptotic Bax and antiapoptotic Bcl-2 in $H_2O_2-stimulated$ SW1353 chondrocytes. Furthermore, schisandrin A effectively abrogated $H_2O_2-induced$ intracellular ROS accumulation and phosphorylation of histone H2AX at serine 139, a widely used marker of DNA damage. Thus, the present study demonstrates that schisandrin A provides protection against $H_2O_2-induced$ apoptosis and DNA damage in SW1353 chondrocytes, possibly by prevention of ROS generation. Collectively, our data indicate that schisandrin A has therapeutic potential in the treatment of oxidative disorders caused by overproduction of ROS.

Anti-oxidative and Anti-cancer Activities by Cell Cycle Regulation of Salsola collina Extract (솔장다리 추출물의 항산화 활성 및 세포주기조절에 의한 항암 활성 분석)

  • Oh, You Na;Jin, Soojung;Park, Hyun-Jin;Kwon, Hyun Ju;Kim, Byung Woo
    • Microbiology and Biotechnology Letters
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    • v.42 no.1
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    • pp.73-81
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    • 2014
  • Salsola collina, also known as Russian thistle, is widely distributed in and around waste facilities, roadsides, and drought and semi-drought areas, and is used as a traditional folk remedy in Chinese medicine for the treatment of hypertension. In this study, we have evaluated the anti-oxidative and anti-cancer activities of the ethanol extract of S. collina Pall. (EESC), and the molecular mechanisms of its anti-cancer effects on human colon carcinoma HT29 cells. EESC exhibited anti-oxidative activity through DPPH radical scavenging capacity and showed cytotoxic activity in a dose-dependent manner in HT29 cells. After EESC treatment, HT29 cells altered their morphology, becoming smaller and irregular in shape. EESC also induced cell accumulation in the G2/M phase in a dose-dependent manner, accompanied by a decrease of cell population in the G1 phase. The G2/M arrest by EESC was associated with the increased expression of cyclin-dependent kinase (CDK) inhibitor p21 and Wee1 kinase, which phosphorylates, or inactivates, Cdc2. EESC treatment induced the phosphorylation of Cdc2 and Cdc25C, and inhibited cyclin A and Cdc25C protein expression. In addition, S arrest was induced by the highest concentration of EESC treatment, associated with a decrease of cyclin A and Cdk2 expression. These findings suggest that EESC may possess remarkable anti-oxidative activity and exert an anti-cancer effect in HT29 cells by cell cycle regulation.

Inhibitory effects of persimmon (Diospyros kaki Thumb.) against diet-induced hypertriglyceridemia/hypercholesterolemia in rats (떫은감 (Diospyros kaki Thumb.)이 흰쥐의 식이성 이상지질혈증에 미치는 영향)

  • Ahn, Youngsook;Regu, Geberea manuel Meron;Oh, Eun Kyoung;Kwon, Oran
    • Journal of Nutrition and Health
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    • v.50 no.3
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    • pp.225-235
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    • 2017
  • Purpose: This study aimed to investigate the potential of freeze-dried persimmon powder (Diospyros kaki Thumb.) to protect against dyslipidemia induced by a high-fat/cholesterol diet (HFD) in a rat model. Methods: Fifty Wistar rats were randomly divided into five groups: normal control (NC), high-fat/cholesterol control (HC), tannin in HFD (HT, 1% of diet), immature persimmon in HFD (HI, 7% of diet), and mature persimmon in HFD (HM, 7% of diet). Tannin was used as a positive control. Biochemical, molecular, and histopathological changes were observed in the blood and liver. Results: We confirmed that a high fat/cholesterol diet successfully induced dyslipidemia, which was characterized by significantly altered lipid profiles in the plasma and liver. However, oxidized low-density lipoprotein levels, histopathological damage in the liver, and hepatic triglyceride levels were significantly reduced in all HT, HI, and HM groups compared to those in the HF group. In contrast, plasma apolipoprotein B level was significantly reduced only in the HT and HM groups, whereas reduction of the LDL-C level was detected only in the HI group. Although HF-induced sterol regulatory element-binding protein (SREBP) gene expression was significantly reduced in all treated groups, downstream gene expression levels varied among the different groups; significant reduction of fatty acid synthase (FAS) and 3-hydroxy-3-methylglutaryl-CoA (HMGCR) gene expression was detected only in the HI group, whereas cholesterol $7{\alpha}$-hydroxylase (CYP7A1) gene expression was significantly elevated only in the HM group. Conclusion: Taken together, the data suggest that protection of LDL oxidation and hepatic lipogenesis might be, at least partly, attributed to tannin in persimmons. However, the identified mechanisms varied up to the maturation stage of persimmon. In the case of immature persimmon, modulation of FAS and HMGCR gene expression was prominent, whereas in the case of mature persimmon, modulation of CYP7A1 gene expression was prominent.

Effects and Molecular Mechanisms of Eupatorium chinensis var. simplicifolium Extract on Abnormal Proliferation of Vascular Smooth Muscle Cells (등골나물추출물의 혈관 평활근 세포의 비정상 증식에 대한 억제 효과 및 분자기작)

  • Kim, Min-Jeong;Kim, Jihee;Lee, Jin-Ho;Kim, Minah;Woo, Keunjung;Kim, Han Sung;Kim, Tack-Joong
    • Journal of Life Science
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    • v.31 no.9
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    • pp.787-795
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    • 2021
  • Eupatorium chinensis var. simplicifolium (EUC) has anti-inflammatory and antioxidant effects. Young sprouts of EUC have been used as food for a long time, and the whole EUC plant has been used as an herbal remedy in oriental medicine. Arteriosclerosis, or chronic inflammation in arterial vessels, is a cardiovascular disease and is involved in various disorders. Cardiovascular diseases such as restenosis and neuropathic hyperplasia are mainly caused by abnormal growth and movement due to multiple growth factors in vascular smooth muscle cells (VSMCs). Platelet-derived growth factor (PDGF) is a mitogen released from damaged vessel walls and is involved in the proliferation and migration of VSMCs. To determine the effects of EUC on the abnormal proliferation and migration of VSMCs, the present study investigated intracellular signaling pathways in PDGF-BB-induced VSMCs treated with and without EUC. Pretreating PDGF-BB-induced VSMCs with EUC tended to effectively decrease cell proliferation and migration. Subsequently, the intracellular growth-related signaling pathways of AKT, phospholipase C gamma (PLC-γ), and mitogen-activated protein kinase (MAPK) were investigated using western blotting to confirm inhibited phosphorylation. Furthermore, flow cytometry data showed that EUC blocked the cell cycle of VSMCs. These results suggest that EUC can inhibit the proliferation and migration of VSMCs by controlling the cell cycle and growth factor receptors. Furthermore, this indicates that EUC can be used as a preventative against cardiovascular disease resulting from abnormal proliferation and migration of VSMCs.

Ethanol Extract of Glycyrrhiza uralensis Protects Against Oxidative Stress-induced DNA Damage and Apoptosis in Retinal Pigment Epithelial Cells (망막색소상피세포에서 감초 추출물의 산화적 스트레스에 의한 DNA 손상 및 apoptosis 유발의 차단 효과)

  • Kim, So Young;Kim, Jeong-Hwan;Kim, Sung Ok;Park, Seh-Kwang;Jeong, Ji-Won;Kim, Mi-Young;Lee, Hyesook;Cheong, JaeHun;Choi, Yung Hyun
    • Journal of Life Science
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    • v.29 no.11
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    • pp.1273-1280
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    • 2019
  • Age-related macular degeneration (AMD) is one of the leading causes of blindness in the elderly population, and damage to retinal pigment epithelial (RPE) cells due to oxidative stress contributes to the development of AMD. Glycyrrhiza uralensis Fischer is one of the most widely used herbal medicines for the treatment of various diseases in Asian countries. Although recent studies indicated that treatment with G. uralensis can protect cells from oxidative stress, its mechanisms in RPE cells remain unknown. We evaluated the effect of a G. uralensis ethanol extract (GU) on $H_2O_2$-induced oxidative injury in ARPE-19 RPE cells. The GU pretreatment attenuated reactive oxygen species (ROS) generation induced by $H_2O_2$, which was associated with induced expression of nuclear factor erythroid-derived-2-like 2 (Nrf2) and heme oxygenase-1 (HO-1). GU also suppressed $H_2O_2$-induced DNA damage and mitochondrial dysfunction. The inhibitory effect of GU on $H_2O_2$-induced apoptosis was associated with the protection of caspase-3 activation. Overall, GU appeared to protect RPE cells from oxidative injury by inhibiting DNA damage and reducing apoptosis. Further studies are needed to determine the regulation of Nrf2-mediated HO-1 expression, but our results suggest the possibility of using GU to reduce the risk of AMD.

Gene Expression of Detoxification Enzymes in Tenebrio molitor after Fungicide Captan Exposure (살진균제인 캡탄 처리 후 갈색거저리의 해독효소 유전자 발현)

  • Jang, Ho am;Baek, Hyoung-Seon;Kim, Bo Bae;Kojour, Maryam Ali Mohammadie;Patnaik, Bharat Bhusan;Jo, Yong Hun;Han, Yeon Soo
    • Korean journal of applied entomology
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    • v.61 no.1
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    • pp.155-163
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    • 2022
  • The application of fungicides is indispensable to global food security, and their use has increased in recent times. Fungicides, directly or indirectly, have impacted insects, leading to genetic and molecular-level changes. Various detoxification mechanisms allow insects to eliminate reactive oxygen species (ROS) toxicity induced by agrochemicals including fungicides. In the present study, we analyzed the mRNA expression levels of detoxifying enzymes in Tenebrio molitor larvae following exposure to non-lethal doses (0.2, 2, and 20 ㎍/µL) of a fungicide captan. Transcripts of peroxidases (POXs), catalases (CATs), superoxide dismutases (SODs), and glutathione-s-transferases (GSTs) were screened from the T. molitor transcriptome database. RT-qPCR analysis showed that TmPOX5 mRNA increased significantly 24 h post-captan exposure. A similar increase was noticed for TmSOD4 mRNA 3 h post-captan exposure. Moreover, the expression of TmCAT2 mRNA increased significantly 24 h post-treatment with 2 ㎍/µL captan. TmGST1 and TmGST3 mRNA expression also increased noticeably after captan exposure. Taken together, these results suggest that TmPOX5 and TmSOD4 mRNA can be used as biomarkers or xenobiotics sensors for captan exposure in T. molitor, while other detoxifying enzymes showed differential expression.

Brief Introduction of Research Progresses in Control and Biocontrol of Clubroot Disease in China

  • He, Yueqiu;Wu, Yixin;He, Pengfei;Li, Xinyu
    • 한국균학회소식:학술대회논문집
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    • 2015.05a
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    • pp.45-46
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    • 2015
  • Clubroot disease of crucifers has occurred since 1957. It has spread to the whole China, especially in the southwest and nourtheast where it causes 30-80% loss in some fields. The disease has being expanded in the recent years as seeds are imported and the floating seedling system practices. For its effective control, the Ministry of Agriculture of China set up a program in 2010 and a research team led by Dr. Yueqiu HE, Yunnan Agricultural University. The team includes 20 main reseachers of 11 universities and 5 institutions. After 5 years, the team has made a lot of progresses in disease occurrence regulation, resources collection, resistance identification and breeding, biological agent exploration, formulation, chemicals evaluation, and control strategy. About 1200 collections of local and commercial crucifers were identified in the field and by artificiall inoculation in the laboratories, 10 resistant cultivars were breeded including 7 Chinese cabbages and 3 cabbages. More than 800 antagostic strains were isolated including bacteria, stretomyces and fungi. Around 100 chemicals were evaluated in the field and greenhouse based on its control effect, among them, 6 showed high control effect, especially fluazinam and cyazofamid could control about 80% the disease. However, fluzinam has negative effect on soil microbes. Clubroot disease could not be controlled by bioagents and chemicals once when the pathogen Plasmodiophora brassicae infected its hosts and set up the parasitic relationship. We found the earlier the pathogent infected its host, the severer the disease was. Therefore, early control was the most effective. For Chinese cabbage, all controlling measures should be taken in the early 30 days because the new infection could not cause severe symptom after 30 days of seeding. For example, a biocontrol agent, Bacillus subtilis Strain XF-1 could control the disease 70%-85% averagely when it mixed with seedling substrate and was drenching 3 times after transplanting, i.e. immediately, 7 days, 14 days. XF-1 has been deeply researched in control mechanisms, its genome, and development and application of biocontrol formulate. It could produce antagonistic protein, enzyme, antibiotics and IAA, which promoted rhizogenesis and growth. Its The genome was sequenced by Illumina/Solexa Genome Analyzer to assembled into 20 scaffolds then the gaps between scaffolds were filled by long fragment PCR amplification to obtain complet genmone with 4,061,186 bp in size. The whole genome was found to have 43.8% GC, 108 tandem repeats with an average of 2.65 copies and 84 transposons. The CDSs were predicted as 3,853 in which 112 CDSs were predicted to secondary metabolite biosynthesis, transport and catabolism. Among those, five NRPS/PKS giant gene clusters being responsible for the biosynthesis of polyketide (pksABCDEFHJLMNRS in size 72.9 kb), surfactin(srfABCD, 26.148 kb, bacilysin(bacABCDE 5.903 kb), bacillibactin(dhbABCEF, 11.774 kb) and fengycin(ppsABCDE, 37.799 kb) have high homolgous to fuction confirmed biosynthesis gene in other strain. Moreover, there are many of key regulatory genes for secondary metabolites from XF-1, such as comABPQKX Z, degQ, sfp, yczE, degU, ycxABCD and ywfG. were also predicted. Therefore, XF-1 has potential of biosynthesis for secondary metabolites surfactin, fengycin, bacillibactin, bacilysin and Bacillaene. Thirty two compounds were detected from cell extracts of XF-1 by MALDI-TOF-MS, including one Macrolactin (m/z 441.06), two fusaricidin (m/z 850.493 and 968.515), one circulocin (m/z 852.509), nine surfactin (m/z 1044.656~1102.652), five iturin (m/z 1096.631~1150.57) and forty fengycin (m/z 1449.79~1543.805). The top three compositions types (contening 56.67% of total extract) are surfactin, iturin and fengycin, in which the most abundant is the surfactin type composition 30.37% of total extract and in second place is the fengycin with 23.28% content with rich diversity of chemical structure, and the smallest one is the iturin with 3.02% content. Moreover, the same main compositions were detected in Bacillus sp.355 which is also a good effects biocontol bacterial for controlling the clubroot of crucifer. Wherefore those compounds surfactin, iturin and fengycin maybe the main active compositions of XF-1 against P. brassicae. Twenty one fengycin type compounds were evaluate by LC-ESI-MS/MS with antifungal activities, including fengycin A $C_{16{\sim}C19}$, fengycin B $C_{14{\sim}C17}$, fengycin C $C_{15{\sim}C18}$, fengycin D $C_{15{\sim}C18}$ and fengycin S $C_{15{\sim}C18}$. Furthermore, one novel compound was identified as Dehydroxyfengycin $C_{17}$ according its MS, 1D and 2D NMR spectral data, which molecular weight is 1488.8480 Da and formula $C_{75}H_{116}N_{12}O_{19}$. The fengycin type compounds (FTCPs $250{\mu}g/mL$) were used to treat the resting spores of P. brassicae ($10^7/mL$) by detecting leakage of the cytoplasm components and cell destruction. After 12 h treatment, the absorbencies at 260 nm (A260) and at 280 nm (A280) increased gradually to approaching the maximum of absorbance, accompanying the collapse of P. brassicae resting spores, and nearly no complete cells were observed at 24 h treatment. The results suggested that the cells could be lyzed by the FTCPs of XF-1, and the diversity of FTCPs was mainly attributed to a mechanism of clubroot disease biocontrol. In the five selected medium MOLP, PSA, LB, Landy and LD, the most suitable for growth of strain medium is MOLP, and the least for strains longevity is the Landy sucrose medium. However, the lipopeptide highest yield is in Landy sucrose medium. The lipopeptides in five medium were analyzed with HPLC, and the results showed that lipopeptides component were same, while their contents from B. subtilis XF-1 fermented in five medium were different. We found that it is the lipopeptides content but ingredients of XF-1 could be impacted by medium and lacking of nutrition seems promoting lipopeptides secretion from XF-1. The volatile components with inhibition fungal Cylindrocarpon spp. activity which were collect in sealed vesel were detected with metheds of HS-SPME-GC-MS in eight biocontrol Bacillus species and four positive mutant strains of XF-1 mutagenized with chemical mutagens, respectively. They have same main volatile components including pyrazine, aldehydes, oxazolidinone and sulfide which are composed of 91.62% in XF-1, in which, the most abundant is the pyrazine type composition with 47.03%, and in second place is the aldehydes with 23.84%, and the third place is oxazolidinone with 15.68%, and the smallest ones is the sulfide with 5.07%.

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STUDY ON THE RELATIONSHIP BETWEEN SEROTONIN SYSTEM AND PSYCHOPATHOLOGY IN TOURETTE'S DISORDER (Tourette씨병의 Serotonin계와 정신병리와의 상호관계에 관한 연구)

  • Cho, Soo-Churl;Shin, Yun-O;Suh, Yoo-Hun
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.7 no.1
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    • pp.77-91
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    • 1996
  • In order to elucidate the biological etiology and the effects of comorbidity on biological variables in tic disorders, plasma serotonin (5-hydroxlfryptamine, 5-HT) and 5-hydroxy- indoleacetic acid (5-HIAA) we.e measured in 87 tic disorders and 30 control subjects. The 87 tic disorder were composed of 45 Tourette's disorder(TS), 22 chronic motor tic disorders (CMT) and 20 transient tic disorders (TTD). Among these patients,43 patients were pure tic disorder (PT), 28 subject also had attention deficit hyperactivity disorder (T+ADHD) and 16 subjects had obsessive compulsive disorders (T+ OCD) as comorbid disorders. The results are summarized as follows : 1) Plasma 5-HT levels showed significant positive correlations with plasma 5-HIAA levels (Pennon r=0.77, p<0.05). 2) Plasma 5-HT and 5-HIAA levels showed no significant correlation with age in tic disorders. 3) Plasma 5-HIAA and 5-HT levels showed no significant correlations with age in control subjects. 4) There was significant difference in plasma 5-HT levels among TS, CMT, TTD and control groups (ANOVA F=34.48, df=3, 113, p<0.01), and post-hoc test using Scheffe method showed significant differences between control and TS, control and CMT, control and ITD groups. But, post-hoc test showed no significant differences between TS and CMT, TS and TTD, CMT and TTD groups. 5) There was significant difference in plasma 5-HIAA levels among TS, CMT, TTD and control groups (ANOVA F=26.48, df=3, 113, p<0.01), and post-hoc test using Scheffe method showed significant differences between control and TS, control and CMT, control and TTD groups. But, post-hoc test showed no significant differences between TS and CMT, TS and TTD, CMT and TID groups.f) There was significant difference in plasma 5-HT and 5-HIAA levels among PT, T+ADHD, T+OCD and contol groups (ANOVA 5-HT, F=37.59, df=3, 113, p<0.01, 5-HIAA, F=27.37, df=3, 113, p<0.01), and post-hoc test using Scheffe method showed signiscant differences between control and PT, control and T+ADHD and control and T+OCB. But, post-hoc test showed no significant differences between PT and T+ADHD, PT and T+ OCD and T+ADHD and T+ OCD. These results show that decreased 5-HT and 5-HIAA levels may play a role in the genesis of tic disorders, but these findings have no significant correlations with the severity of tic disorders. And the comorbid disorders of tics may have minimal effects on the biochemical abnormalities. Future studies must be focused on the effects of serotonin agonists and antagonists on tic disorders and molecular biological methodology may enhance to elucidate the mechanisms of these abnormal findings.

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Regulatory Mechanism of Insulin-Like Growth Factor Binding Protein-3 in Non-Small Cell Lung Cancer (비소세포성 폐암에서 인슐린 양 성장 인자 결합 단백질-3의 발현 조절 기전)

  • Chang, Yoon Soo;Lee, Ho-Young;Kim, Young Sam;Kim, Hyung Jung;Chang, Joon;Ahn, Chul Min;Kim, Sung Kyu;Kim, Se Kyu
    • Tuberculosis and Respiratory Diseases
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    • v.56 no.5
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    • pp.465-484
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    • 2004
  • Background : Insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3) inhibits the proliferation of non-small cell lung cancer (NSCLC) cells by inducing apoptosis. Methods : In this study, we investigated whether hypermethylation of IGFBP-3 promoter play an important role in the loss of IGFBP-3 expression in NSCLC. We also studied the mechanisms that mediate the silencing of IGFBP-3 expression in the cell lines which have hypermethylated IGFBP-3 promoter. Results : The IGFBP-3 promoter has hypermethylation in 7 of 15 (46.7%) NSCLC cell lines and 16 (69.7%) of 23, 7 (77.8%) of 9, 4 (80%) of 5, 4 (66.7 %) of 6, and 6 (100%) of 6 tumor specimens from patients with stage I, II, IIIA, IIIB, and IV NSCLC, respectively. The methylation status correlated with the level of protein and mRNA in NSCLC cell lines. Expression of IGFBP-3 was restored by the demethylating agent 5'-aza-2'-deoxycytidine (5'-aza-dC) in a subset of NSCLC cell lines. The Sp-1/ Sp-3 binding element in the IGFBP-3 promoter, important for promoter activity, was methylated in the NSCLC cell lines which have reduced IGFBP-3 expression and the methylation of this element suppressed the binding of the Sp-1 transcription factor. A ChIP assay showed that the methylation status of the IGFBP-3 promoter influenced the binding of Sp-1, methyl-CpG binding protein-2 (MeCP2), and histone deacetylase (HDAC) to Sp-1/Sp-3 binding element, which were reversed by by 5'-aza-dC. In vitro methylation of the IGFBP-3 promoter containing the Sp-1/Sp-3 binding element significantly reduced promoter activity, which was further suppressed by the overexpression of MeCP2. This reduction in activity was rescued by 5'-aza-dC. Conclusion : These findings indicate that hypermethylation of the IGFBP-3 promoter is one mechanism by which IGFBP-3 expression is silenced and MeCP2, with recruitment of HDAC, may play a role in silencing of IGFBP-3 expression. The frequency of this abnormality is also associated with advanced stages among the patients with NSCLC, suggesting that IGFBP-3 plays an important role in lung carcinogenesis/progression and that the promoter methylation status of IGFBP-3 may be a marker for early molecular detection and/or for monitoring chemoprevention efforts.