수은화합물에 의한 EMT-6 세포의 nitric oxide 생성과 관련된 요인에 관한 연구

염정호 大韓産業醫學會 1997 대한직업환경의학회지 Vol.9 No.1

The effects of several factors on the nitrite synthesis were observed in the culture of EMT-6 cells which are originated from mammary adenocarcinoma of Balb/c mouse. The cells were cultured in Dulbecco's Modified Eagle's Medium containing 10% fetal calf serum. Amounts of nitrite in the culture media after 24 and 36 hours of culture were about 2fold, and 3-fold of those measured after 12 hours respectively. There were very close associations between the amounts of nitrite measured in the culture media. A significant nitrite synthesis by EMT-6 cells occured when IL-1 was added to the culture medium with other cytokines as IFNγ or TNFα One of each cytokines were less effective as an inducer of nitrite than the combinations of cytokines. When mercury chloride of cinnamte was added in the culture medium, the nitrite synthesis was dose-dependently decreased by the concentration of these materials. The viability of EMT-6 cells were kept on 95% or above in 36 hours after beginning of culture without and specific additives except cytokines. While after 48 hours it went down to 85% or less. These viability were decreased by the prolongation of culture time(48 hours or more), the addition of TNFα to cytokine mixture, and the higher concentrations of mercury chloride of cinnamate to culture medium. Simultaneous addition of the equimolar dose of selenium completely prevented mercurial compounds-induced inhibitions of nitrite syntheses. But the single addition of selenium neither influenced the viability of cells nor the productions of nitrite. These results suggest that the disorder of cell mediated immunity by mercurial compounds could be related to the inhibition of nitric oxide synthesis and selenium decreased the cytotoxicity of mercurial compounds.

니켈 및 코발트의 세포독성 기전에서 Nitric Oxide의 역할

염정호,오경재,유영천 대한산업의학회 2001 대한직업환경의학회지 Vol.13 No.3

목적 : 이 연구는 RAW 264.7 cell의 배양조건에 니켈, 코발트 또는 iNOS의 competitive inhibitor인 NMLA를 여러 조건으로 처리하여 NO 생성의 변조유무 및 이와 관련된 ATP 생성과 세포생존율의 변조양상을 관찰하므로써 니켈 및 코발트가 염증반응을 일으키는 세포독성 과정에서의 NO 역할에 대해 알아보고자 실시하였다. 방법 : Balb/c 마우스의 복강내에 Abelson leukemia virus(A-MuLV)를 주입하여 발생시킨 대식세포주 RAW 264.7 세포의 배양조건에 니켈, 코발트 또는 iNOS의 특이억제체인 NMLA를 여러 조건으로 처리하여 NO 생성의 변조유무 및 이와 관련된 ATP 생성과 세포생존율의 변조양상을 관찰하였다. 세포생존율은 trypan-blue dye exclusion 방법을 이용하였으며 NO는 Hibbs 등(1987)의 방법에 따라 그 대사물질인 nitrite(NO2-)의 측정을 통해 간접 측정하였다. 또한, ATP는 세포막을 파괴한 후 luciferase와 ATP의 반응에 따른 발광정도를 luminometer로 측정하였다. 한편, 각 실험조건에서의 세포의 형태학적 변화는 inverted microscope(×400)를 이용하여 관찰하였다. 결과 : 기본배양조건에 cytokines과 여러 농도의 니켈 또는 코발트의 단독 및 동시첨가의 경우 두 금속 모두 50 μM, 48시간을 기점으로 NO 생성량은 첨가농도의 증가에 따라 용량의존적으로 증가하다가 그 이상의 농도 및 시간에서는 현저히 감소하였으며, 동일 조건에서의 세포생존율은 저 농도에서는 대조군과 차이가 없었으나 전반적으로 첨가한 금속의 농도증가에 따라 용량 및 시간 경과에 따라서 감소하는 경향을 보였다. 두 금속 모두 세포생존율 및 NO의 생성율이 높게 유지되는 50 μM, 48시간 배양 조건에서의 결과 또한, 니켈 및 코발트 첨가는 두 금속 모두 cytokines만의 첨가시보다 NO 생성을 더욱 증가시켰으며 ATP 생성정도는 NO 생성 양상과는 반대로 니켈 및 코발트 모두 대조군보다 현저히 감소하였다. 한편 동일 조건에서의 세포생존율은 ATP 감소양상과 비슷하였으며, 이러한 결과들은 두 금속의 동시첨가시 상가(additive)작용으로 나타났다. 한편, 니켈 및 코발트를 단독 또는 동시 첨가한 경우 모두에서 나타났던 NO의 증가와 ATP 감소 및 세포생존율의 감소는 iNOS 억제제인 NMLA를 전처리로 NO 생성은 감소하고 ATP 및 세포생존율은 증가하여 모든 경우에서 대조군 수준으로 완전히 회복되었다. 또한, 이러한 경향은 RAW 264.7 세포를 여러 실험 조건으로 배양한 후 세포상태를 inverted microscope로 관찰한 결과에서도 동일한 결과를 나타내어 니켈 또는 코발트의 첨가로 나타났던 전반적인 세포의 위축과 불규칙한 외형들은 NMLA의 전처리에서는 나타나지 않았다. 결론 : 이상의 결과에서, 니켈 및 코발트는 대식세포의 NO 생성을 증가시키며 이들 금속에 의한 ATP 생성 억제는 그 간 알려졌던 NO의 궁극적인 독성양상인 ATP 생성억제와 동일한 결과로서, 니켈 및 코발트는 대식세포를 활성화시켜 NO 생성을 증가시키고 NO는 ATP 생성을 억제하여 생존율을 감소시키는 것으로 사료된다. 한편, 니켈 및 코발트의 독성효과들은 NMLA를 전처리로 완전하게 억제되고 있어 니켈 및 코발트의 독성은 대부분 NO에 의해 매개됨을 알 수 있었다. 따라서 NO는 니켈 및 코발트의 염증유발 과정에서 중요한 매개역할을 수행하리라 사료된다. Objectives : The nickel and cobalt present in many industrial working environments and consumer products. They are two of the leading causes of allergic contact dermatitis, which is a typical delayed(type IV) hypersensitivity reaction. However, the mechanism by which nickel and cobalt causes this pathology is not well known. The nickel and cobalt induced contact dermatitis is mediated primarily through macrophages. This mechanism is similar to the autotoxicity procedure for NO. Therefore, this study was designed to examine whether the metals could modulate NO productihb and how the metals may affect ATP production and cell viability. In summary, the purpose of this study was to elucidate the role of NO in the nickel and cobalt induced cytotoxicity. Methods : This study is based on observations of cultures of RAW 264.7 cells which are originated from a tumor of Balb/c mouse that was induced by Abelson murine leukemia virus. RAW 264.7 cells were treated with either Ni, Co, Ni plus Co, or N-monomethyl-L- arginine(NMLA) for 24-72 h. The cytotoxicity of the nickel and cobalt was measured by cell viability and NO2-, and mitochondrial function was evaluated by adenosine triphosphate(ATP) production in RAW 264.7 cells. In addition, the morphology of cells was observed using an inverted microsope. Results : The NO2- synthesis of RAW 264.7 cells increased with increasing concentrations of Ni and Co up to 50 μM after 24 and 48 h of exposure to Ni and Co but then decreased if the concentration was greater than 50 μM and the time period was greater than 48 h. However, the viability of cells was decreased by Ni and Co exposure in a dose and time dependent manner. Therefore, 50 μM Ni or Co and 48 h of treatment were used in this study. A complete inhibition of NO2- synthesis by Ni or/and Co occurred when iNOS inhibitor, NMLA, were pretreated prior to addition of Ni or/and Co, whereas Ni or/and Co induced decrease of synthesis of ATP and viability completely recovered when NMLA were pretreated prior to addition of Ni or/and Co. Ni or/and Co(50 μM) induced the characteristic morphological features of cytotoxicity which is characterized by a shrinkage of cytoplasm and irregular shape of the cells, but the pretreatment of NMLA resulted in a recovered morphological change of the cells to their normal appearance. Conclusions : These results suggest that NO plays an important role in the pathogenesis of the cytotoxicity of nickel and cobalt, and nickel and cobalt may exert their toxicities by means of modulation of NO prduction. The results from this study may facilitate further understanding the role of NO of nickel and cobalt induced immune and inflammatory processes.

수은화합물이 마우스 복강대식세포와 EMT-6 세포에 미치는 효과

고대하,염정호,기노석,오경재,권근상,김성엽,김남송 大韓産業醫學會 1996 대한직업환경의학회지 Vol.8 No.2

Balb/c 마우스의 복강대식세포 및 유선암에서 기원한 EMT-6 세포를 배양하는 조건에 여러농도의 수은을 첨가하여 nitrite와 nitrate 생성의 변화를 관찰한 결과는 다음과 같다. 복강대식세포 및 EMT-6 세포가 생성하는 nitrite와 nitrate 양은 배양시작 12시간째의 생성량에 비해 24시간 후에는 2배, 36시간 후에는 3배의 농도로 측정되어 된다. 이때 nitrite와 nitrate 농도사이에는 매우 높은 상관관계를 나타냈다. 수은첨가에 따라 nitrite 및 nitrate 생성량은 용량의존적 관계로 현저한 감소를 보이며, 24시간 또는 36시간 후의 세포생존률도 역시 수은농도에 비례하여 감소되는데, 복강대식세포의 생존률이 EMT-6 세포의 생존률보다 더욱 큰 폭으로 감소하였다. 이상의 결과로 배양조건에 수은의 첨가로 인하여 nitrite 및 nitrate 생성량이 감소하는 바 수은이 면역세포의 대사과정에 영향을 주어 nitric oxide 생 성능을 억제시키며, 결국 세포성 면역을 저하시키는 것으로 사료된다. The effect of treatment of mercury chloride on the nitrite and nitrate synthesis was observed in peritoneal macrophages from Balb/c mice and EMT-6 cells in vitro. The cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with cytokines. Amounts of nitrite and nitrate in the culture media after 24 and 36 hours of culture were about 2-fold, 3-fold of those measured after 12 hours respectively. There were very close associations between the amounts of nitrite and nitrate measured in the culture media, according to culture time. The survival rate of peritoneal macrophages was significantly decreased by mercury chloride added into the media in dose-dependent manner, however the survivals of EMT-6 cells were not influenced by mercury chloride concentration in media. Nitrite and nitrate syntheses were dose-dependently decreased by mercury chloride added in culture media. These results reported here suggest that the disorder of cell mediated immunity by mercurials could be related to the inhibition of nitric oxide synthesis which seems to be caused by the inhibition of metabolism of cells.

천안시 도로변의 NO₂및 SO₂오염도 측정에 관한 연구

손부순,염윤기,김종오,문정숙 한양대학교 환경및산업의학연구소 2000 環境과 産業醫學 Vol.9 No.1

This study's goale to find out the degree of the air pollution caused by vehicle emissions and to collect basic data for alternative plan in the improvement of the quality of the air by searching for the quality of the air around the road(in front of Chunan station, Terminal intersection, at Bangiugan five forked road, Chunanro intersection) in Chunan. NO2 and SO2 were measured as a object for this study in winter time and in summer time respectively. There has been an rapid increase in population and industrial complex has been built up in Chunan area. Therefore an increase in the number of vehicles and the use of domestic fuel has followed by that. So more studies of that and the effort for the improvement in the quality of the air will have to be made.

Transgenic potato expressing Aβ reduce Aβ burden in Alzheimer’s disease mouse model

Youm, Jung Won,Kim, Hee,Han, Jee Hye Lo,Jang, Chang Hwan,Ha, Hee Jin,Mook-Jung, Inhee,Jeon, Jae Heung,Choi, Cheol Yong,Kim, Young Ho,Kim, Hyun Soon,Joung, Hyouk Elsevier 2005 FEBS letters Vol.579 No.30

<P><B>Abstract</B></P><P>Beta amyloid (Aβ) is believed one of the major pathogens of Alzheimer’s disease (AD), and the reduction of Aβ is considered a primary therapeutic target. Immunization with Aβ can reduce Aβ burden and pathological features in transgenic AD model mice. Transgenic potato plants were made using genes encoding 5 tandem repeats of Aβ1–42 peptides with an ER retention signal. Amyloid precursor protein transgenic mice (Tg2576) fed with transgenic potato tubers with adjuvant showed a primary immune response and a partial reduction of Aβ burden in the brain. Thus, Aβ tandem repeats can be expressed in transgenic potato plants to form immunologically functional Aβ, and these potatoes has a potential to be used for the prevention and treatment of AD.</P>

납 취급 근로자의 Monte-Carlo simulation을 이용한 노출 및 건강위해성평가

염정호 ( Jung Ho Youm ),권근상 ( Keun Sang Kwon ),이주형 ( Ju Hyoung Lee ),정주원 ( Joo Won Jeong ) 한국산업위생학회 2006 한국산업보건학회지 Vol.16 No.2

Objective: This study was conducted to quantify chronic lead exposure from various media(ie. working environment, food, ambient air), and to certify the usefulness of exposure assessment using Monte-Carlo simulation in the fields of occupational health. Methods: Data were obtained from Korean Industrial Health Association, Korea Food and Drug Administration, and the Ministry of Environment. Then lead worker`s exposure was estimated indirectly from various media and parameters (ie. volume inhaled, body weight, dietary intake, etc.). Uncertainty was analyzed by Monte Carlo simulation with Crystal Ball software. Exposure doses and hazard indices were simulated with various hypothetical scenarios including weekly working hours and respiratory protective equipment. Results: Without respiratory protective equipment, the total exposure dose per kilogram of body weight of lead workers was estimated as 5.45×10(-3) mg/kg/day, and hazard index was estimated as 2.26, and exposure contributions were calculated as follows: working environment(82.42%); foods(17.57%); and ambient air(0.01%). But, if working condition has changed-reduction of working hours and using respiratory protective equipment, the total exposure dose per kilogram of body weight was estimated between 1.34×10(-3)-1.49×10(-3) mg/kg/day, and hazard index was estimated between 0.56-0.62. Conclusions: This study suggested that occurrence of hazardous impact(ie. increased blood pressure) through lifetime lead exposure would be expected, and that the Monte-Carlo simulation was useful for the fields of occupational health.

보건진료원 업무활동의 시대에 따른 비교

염정호(Jung-Ho Youm),권근상(Keun-Sang Kwon) 한국농촌의학 지역보건학회 2004 농촌의학·지역보건 Vol.29 No.1

Anti‐ageing effects of a new synthetic sphingolipid (K6EAA‐L12) on aged murine skin

Jung, Minyoung,Lee, Sanghoon,Park, Hwa‐,young,Youm, Jong‐,Kyung,Jeong, Sekyoo,Bae, Jonghwan,Kwon, Mi Jung,Park, Byeong Deog,Lee, Seung Hun,Choi, Eung Ho Blackwell Publishing Ltd 2011 Experimental dermatology Vol.20 No.4

<P><B>Abstract: </B> Recently, we reported on the anti‐ageing effects of K6PC‐5. This compound induced keratinocyte differentiation and fibroblast proliferation by increasing sphingosine‐1 phosphate synthesis. We performed this study to confirm the anti‐ageing effects of new synthetic products (the K6EAA series) derived from K6PC‐5 through an amino group induction. Cellular responses such as differentiation, proliferation and calcium mobilization were investigated using cultured human keratinocytes and fibroblasts. Also, we measured the expressions of collagen mRNA and protein using real time RT‐PCR and ELISA, respectively. The K6EAA‐L12 product, selected by <I>in vitro</I> screening, was evaluated for anti‐ageing effects on intrinsically and extrinsically (photo) aged models of hairless mice. In the intrinsically aged murine skin, K6EAA‐L12 showed anti‐ageing effects by activating collagen synthesis, eventually causing dermal thickening. Also, in the photo‐aged skin, the dermal collagen density and dermal thickness were increased. In photo‐aged murine skin, K6EAA‐L12 increased stratum corneum integrity by increasing corneodesmosome density and improved the barrier recovery rate. However, there were no changes in the expressions of epidermal differentiation maker proteins. In conclusion, topical K6EAA‐L12, a new synthetic K6PC‐5 derivative, improves intrinsically and extrinsically (photo) aged skin by increasing the collagen density and improving the skin barrier function.</P>

Stable Maintenance of Human Beta Amyloid in Transgenic Potato

Jung Won Youm,Jae Heung Jeon,Hee Kim,Young Ho Kim,Hyouk Joung,Hyun Soon Kim 한국원예학회 2008 Horticulture, Environment, and Biotechnology Vol.49 No.1

Beta amyloid (Aβ) is a potent oral immunogen with potential utility as a vaccine against Alzheimer's disease (AD). Our previous work investigated the ability of a protein comprised of five tandem repeats of Aβ42(5Aβ42) to induce an immune response in a transgenic AD mouse model, and demonstrated that immunization with potato-derived 5Aβ42 reduced the Aβburden as well as many of the AD-associated pathological features. To provide a potato-derived 5Aβas vaccine material, the stable yield of 5Aβprotein through constant expression of introduced transgene is the most important factor. In the present study, we confirmed that the 5Aβ42 transgene were inherited and stably expressed in in vitro vegetative propagation over a period of 3 years without silencing. The 5Aβ42 protein, too, was expressed well without change of its antigenicity in transgenic potato. Stable storage conditions were vital in maintaining the stability of the potato-derived 5Aβ42 protein, and activity of the protein was not affected following up to three months’ storage at low temperature.

The Effect of Various Factors on Variability of Retinal Nerve Fiber Layer Thickness Measurements Using Optical Coherence Tomography

Youm, Dong Ju,Kim, Hyunjoong,Shim, Seong Hee,Jang, Hyo Ju,Kim, Joon Mo,Park, Ki Ho,Choi, Chul Young,Cho, Jung Gon The Korean Ophthalmological Society 2012 Korean Journal of Ophthalmology Vol.26 No.2

<P><B>Purpose</B></P><P>To evaluate the effects of various factors on the variability of retinal nerve fiber layer (RNFL) thickness measurements using the Stratus optical coherence tomography (OCT) in normal and glaucomatous eyes.</P><P><B>Methods</B></P><P>Four hundred seventy-four subjects (103 normal eyes and 371 glaucomatous eyes) were scanned to determine the RNFL thickness measurements using the Stratus OCT. Measurements were obtained twice during the same day. The standard deviation (SD) was used to compare the variability in RNFL thickness measurements of the normal subjects to that of the glaucomatous patients. Multivariate regression analysis was used to evaluate which covariates were independent predictors of SD in overall mean RNFL thickness.</P><P><B>Results</B></P><P>The mean SD of all RNFL thickness measurements was larger in the glaucoma group except in one sector. In the multivariate regression analysis, the average signal strength (SS) and the relative SS change (difference in SS between initial and repeat scans, divided by initial SS) were independent predictors of the SD in the RNFL thickness measurements (partial R<SUP>2</SUP> = 0.018, 0.013; <I>p</I> = 0.016, 0.040, respectively).</P><P><B>Conclusions</B></P><P>Glaucomatous eyes tend to be more variable than normal eyes in RNFL thickness measurement using the Straus OCT. The average SS and the relative SS changes appear to correlate with the variability in RNFL thickness measurement. Therefore, the results of the RNFL analysis should not be interpreted independently of these factors.</P>