• 동의생리병리학회지
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• 제17권5호
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• pp.1202-1207
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• 2003

In order to clarify the neuroprotective effect of Cornu Saigae Tataricae(CST) water extract on cultured mouse spinal motor neuron damaged by hydrogen peroxide (H₂O₂), MTT [3-(4,5-dimethylthiazole-2-yl)- 2,5-diphenyltetrazolium bromide] assay, LDH (Lactate Dehydrogenase) activity assay and SRB (Sulforhodamine B) assay were carried out after the cultured mouse spinal motor neuron were preincubated with various concentrations of CST water extract for 3 hours prior to exposure of hydrogen peroxide Cell viability of cultured mouse spinal motor neurons exposed to various concentrations of hydrogen peroxide for 6 hours was decreased in a dose-dependent manner. MTT50 values were 40 uM hydrogen peroxide. Cultured mouse spinal motor neurons in the medium containing various concentration of hydrogen peroxide for 6 hours showed increasing of LDH activity and decreasing of total protein synthesis. We know that hydrogen peroxide was toxic on cultured spinal motor neurons. Pretreatment of CST water extract for 3 hours following hydrogen peroxide prevented the hydrogen peroxide-induced neurotoxicity such as increasing of LDH activity and decreasing of total protein synthesis. These results suggest that hydrogen peroxide shows toxic effect on cultured spinal motor neurons and CST water extract is highly effective in protecting the neurotoxicity induced by hydrogen peroxide.

• Journal of Microbiology and Biotechnology
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• 제22권2호
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• pp.199-206
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• 2012

Naturally immobilized tannase (tannin acyl hydrolase, E.C. 3.1.1.20) has many advantages, as it avoids the expensive and laborious operation of isolation, purification, and immobilization, plus it is highly stable in adverse pH and temperature. However, in the case of cell-associated enzymes, since the enzyme is associated with the biomass, separation of the pure biomass is necessary. However, tannic acid, a known inducer of tannase, forms insoluble complexes with media proteins, making it difficult to separate pure biomass. Therefore, this study optimizes the production of cell-associated tannase using a "protein-tannin complex" free media. An exploratory study was first conducted in shake-flasks to select the inducer, carbon source, and nitrogen sources. As a result it was found that gallic acid induces tannase synthesis, a tryptose broth gives higher biomass, and lactose supplementation is beneficial. The medium was then optimized using response surface methodology based on the full factorial central composite design in a 3 l bioreactor. A $2^3$ factorial design augmented by 7 axial points (${\alpha}$ = 1.682) and 2 replicates at the center point was implemented in 17 experiments. A mathematical model was also developed to show the effect of each medium component and their interactions on the production of cell-associated tannase. The validity of the proposed model was verified, and the optimized medium was shown to produce maximum cell-associated tannase activity of 9.65 U/l, which is 93.8% higher than the activity in the basal medium, after 12 h at pH 5.0, $30^{\circ}C$. The optimum medium consists of 38 g/l lactose, 50 g/l tryptose, and 2.8 g/l gallic acid.

• 생명과학회지
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• 제26권2호
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• pp.265-274
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• 2016

Toxin-antitoxin (TA) system은 박테리아와 고세균에서 진화적으로 보존되어 흔히 발견되는 유전적 모듈이다. 기본적으로 이 시스템은 세포 내 toxin과 그들의 억제자로 작용하는 antitoxin으로 구성되어있으며, 현재 총 다섯가지 유형으로 구분된다. 공통적으로 toxin은 스트레스 조건에서 활성화됨으로써 세포 내 다양한 과정을 억제하는 활성을 가지는데 이는 결과적으로 세포 사멸 혹은 가역적인 생장 저해를 일으킨다. Toxin의 이러한 효과들은 유전자 발현의 조절, 성장 조절, programmed cell arrest, programmed cell death, persister cell의 형성, 박테리오파지 방어기작, 가동성 유전인자의 안정화, 플라스미드 유지 기작 등 다양한 생리학적 역할을 나타낸다. 그러므로 TA system은 일반적인 스트레스 반응모듈로서 여겨진다. 하지만 이를 역이용한다면 TA system으로부터 toxin을 활성화 시키는 인자를 개발하여 새로운 항균 물질로 이용할 수 있다. 그뿐만 아니라 TA system은 toxin의 세포 사멸 효과를 이용하여 원하는 타겟 유전자가 존재하는 세포만 선택적으로 살아남도록 하는 효율적인 클로닝 전략에 이용될 수 있다. 또한, toxin의 서열 특이적 리보핵산 가수분해효소 활성을 이용하여 타겟 단백질 이외의 단백질 합성을 막아 효과적인 단일 단백질 대량 생산을 위해서도 이용할 수 있다. 더 나아가 일부 TA system의 toxin은 진핵 세포에서도 세포 독성을 나타내기 때문에 암세포, 바이러스 감염 세포에서 toxin의 발현을 유도하여 세포사멸을 일으킴으로써 인간의 질병 치료로 이어질 수 있다.

• 생명과학회지
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• 제17권5호
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• pp.687-693
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• 2007

사람의 섬유아세포인 GM10을 사용하여 glucose의 배양조건에 다른 물질대사 및 IGFBP-3 발현을 살펴본 결과, glucose 농도에 따른 glucose 소비와 triglyceride 축적 수준은 고농도 glucose 배양 조건에서 증가한 반면, 총 단백질 함량은 고농도 glucose배양 조건에서 시간의 경과에 따라 감소하였다. 또한 고농도 glucose 배양 조건에서 5일 동안 배양한 세포 배양액내의 유리아미노산 함량은 저농도보다 고농도 glucose 배양 조건에서 높게 나타났다. IGFBP-3 단백질 수준과 mRNA수준은 저농도 glucose배양 조건에서 증가하였으나, IGFBP-3 단백질 분해효소에 따른 영향은 없었다. 이상의 결과에서 glucose 배양조건에 따른 물질대사는 부분적으로 세포를 이용한 당뇨병 모델 실험에서 in vivo와 같은 결과를 얻지 못하였지만, IGFs와 같은 세포 성장인자에 대한 연구를 통해 세포수준의 당뇨병 모델화가 가능하다고 여겨진다.

• Applied Biological Chemistry
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• 제40권5호
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• pp.375-379
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• 1997

리보즘불활성화 단백질(Ribosome-inactivating protein, RIP)을 생성하는 식물을 탐색하여 그중 호박$(Cucurbita\;moschata\;D_{UCHESNE})$ 잎에서 ammonium sulfate 침전, DE 52-Cellulose, S-Sepharose, FPLC Superose 12 HR, FPLC Mono-S column chromatography에 의하여 ribosome-Inactivating 활성이 있는 단백질(PR 1, PRIP 2)을 분리하였다. 정제된 단백질의 분자량은 SDS-PAGE에서 약 31,000과 30,500인 염기성 단백질로서, 특히 PRIP 1은 열에도 안정하여 $50^{\circ}C$에서 30분간 처리한 경우에도 활성이 유지되었다. 이 단백질들의 ribosome-inactivating 활성을 in vitro translation system에서 측정한 결과 50% 활성저해농도 $(IC_{50})$는 PRIP 1은 0.82nM, PRIP 2은 0.79 nM이었다. PRIP 1과 PRIP 2의 N-말단부분의 아미노산 서열을 분석하여, 이미 밝혀진 리보즘불활성화 단백질들과 아미노산서열의 유사성을 분석해 본 결과, PRIP 1은 Luffa cylindrica에서 분리된 Luffin B 및 Trichosanthes kirilowii Maximowicz에서 분리된 Trichokirin과, PRE 2은 Momordia charantia에서 분리된 Momordin II 및 MAP 30과 유사성이 매우 높았다.

• Animal cells and systems
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• 제1권4호
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• pp.641-646
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• 1997

Lysophosphatidic acid (LPA; 1-acyl-glycerol-3-phosphate) has been known as an intercellular phospholipid messenger with a wide range of biological activities. In this study, the effect of LPA on both the proliferation and differentiation of rat E63 myoblasts has been investigated. In the serum-free Insulin-Transferrin-Selenium (ITS) media, the proliferation of E63 cells was largely restricted. Addition of LPA into the ITS media strongly promoted the cell proliferation and resulted in two to four fold increase of cell number. Furthermore, it appeared to increase the percent fusion in a dose-dependent manner up to 15 ug/ml. The synthesis of myosin heavy chain (MHC) was increased by LPA as well. These results indicate that LPA is able to promote both cell proliferation and differentiation in rat E63 myoblasts. Suramin, known to have uncoupling activity on growth factor-receptor interaction, was tested for antagonistic activity in myoblast proliferation and differentiation. Myoblasts grown in the ITS medium containing LPA were able to proliferate well even in the presence high concentration of suramin whereas myoblast differentiation was completely blocked by 30 ug/ml of suramin. The inhibitory effect of suramin on the myoblast differentiation was completely reversible by removing the suramin. This result indicates that the intracellular signaling pathway of LPA leading to cell proliferation might be distinct from that leading to cell differentiation on E63 myoblasts. Also, the antagonistic effect of suramin suggests that the differentiation activity elicited by LPA might be mediated by a specific G protein-coupled receptor.

• 한국식품영양과학회지
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• 제32권3호
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• pp.428-436
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• 2003

Carotenoids는 항암 효과가 있는 것으로 알려져 있으나 각각의 carotenoids가 대장암에 미치는 영향에 대해서는 명확하게 밝혀진 바가 없다. 본 연구에서는 4가지 종류의 carotenoids가 인간의 대장에서 유래한 암세포인 HT-29 세포의 증식에 미치는 영향을 조사하였다. $\alpha$-carotene, $\beta$-carotene, lutein lycopene을 농도를 달리 하여 세포 배양액 에 첨가하여 살아있는 세포의 수를 측정한 결과 $\beta$-carotene는 세포의 증식을 다소 증가시키는 반면 $\alpha$-carotene, lutein, lcopene은 세포의 증식을 감소하였다. 세포의 증식을 억제한 carotenoids 중에서 lycopene이 그 효과가 가장 컸다. ErbB receptor family는 세포의 증식을 촉진하고 대장암에서 그 발현이 증가된 것으로 보고되었기 때문에 lycopene이 heregulin-ErbB3 signaling을 억제하는지를 조사하였다. Lycopene는 ErbB2 단백질을 감소하였고 ErbB3 단백질의 변화를 초래하였다. Heregulin을 첨가하여 인산화를 유도한 경우 ErbB3의 인산화, ErbB3와 p85의 결합, Akt 인산화가 lycopene에 의해 억제되었다. 이 결과들은 carotenoids 중 lycopene이 대장암 세포 증식 억제 효과가 가장 크고, 대장암 세포의 DNA 합성을 억제하고 apoptosis를 유도하는 lycopene효과의 일부는 Erb-B3와 Akt의 인산화 감소에 기인하는 것임을 나타낸다.

• 한국축산식품학회지
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• 제30권3호
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• pp.443-448
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• 2010

유제품, 김치 및 신생아 분변 등에서 유산균을 분리하여 우유 casein을 분해시켜 배양상등액에 존재하는 serine의 함량을 측정함으로써 간접적으로 CPP 생산을 평가하였다. CPP 생산 능력은 OPA방법으로 측정했을 때 E. faecalis A-2 균주가 1.244 mg/mL로 가장 많은 peptide를 생산 하였다. 본 실험에 사용된 유산균의 경우, 세포내 효소와 세포외 효소로 각각 나누어 proteolytic 활성을 평가한 결과 세포내 효소에 의한 proteolytic 활성은 E. faecalis A-6 균주가 가장 높은 것으로 나타났으며, 세포외 효소에 의한 proteolytic 활성은 L. plantarum A-14 균주에서 가장 높게 나타났다. 가용성 칼슘함량은 Leuconostoc mesenteroides A-1(11 mg/dL), E. durans A-16(10.481 mg/dL), 그리고 L. planatarum A-3(10.356 mg/dL) 균주의 경우에는 대조구보다 높은 유리 칼슘함량을 나타내었다. 따라서 이러한 유산균을 이용한다면 소장 내에서 칼슘 흡수를 극대화시킬수 있는 장점이 있어 이들 유산균을 이용한 고칼슘 제품 개발이 가능할 것이다.

• Applied Microscopy
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• 제26권4호
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• pp.431-446
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• 1996

This experiment was performed to study the ultrastructural changes of the juxtaglomerular cell of mice following subcutaneous injection of heavy metallic agents. Male mice were divided into normal and experimental groups. The mice were subcutaneouly injected with $HgCl_2$ (2mg, 5mg or 10 mg/Kg/BW) or with $K_{2}Cr_{2}O_7$(5 mg, 10 mg or 20 mg/Kg/BW). Mice were sacrificed on 6 hours, 3 days and 14 days after the injection. Kidneys were fixed in the 2.5% glutaraldehyde-1.5% paraformaldehyde solution, followed by refixation in the 1% osmium tetroxide solution. Dehydrated blocks were embedded in araldite mixture. The sections were cut on a LKB-V ultratome, and ultrathin sections stained with uranyl acetate and lead citrate were observed with JEM 100CX II electron microscope. The results were as follow: 1. Juxtaglomerular cell of the experimental groups showed some alterations, especially in the structures of protein synthesis including dilations and degradations of granular endoplasmic reticula, atrophy of Golgi complex, and numerous free ribosomes in the cytoplasm. 2. Juxtaglomerular cells treated groups showed a number of vacuoles, protogranules and some myelin figures in the cytoplasm, especially in the earlier groups. 3. Juxtaglomerular cells of treated groups, contained a large number of secretory granules showing variable electron densities and pleomorphism in later groups (2 weeks). From the above results, it was concluded that, the mercuric chloride or potassium bichromate induces acute renin release from juxtaglomerular cells of the mice, but many juxtaglomerular cells may secrete prematured secretory granules, or the synthetic system of the cell can not perform normal function.

• 미생물과산업
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• 제25권1호
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• pp.2-9
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• 1999

A study was made on enzymes of carbohydrate metabolism in T. concretivorus grown with and without glucose. The present results show that T. concretivorus possesses high activities of pentose shunt pathway and related enzymes, glucokinase, G-6-P dehydrogenase, 6-PG dehydrogenase, and phosphoglucoisomerase, but low activities of enzymes unique to EMP(fructose-1,6-diphosphate aldolase). Although the synthesis of the latter enzymes remains largely unaffected by the growth enviroment, that of the former is stimulated by glucose. And the failure to detect ED pathway enzymes in cells grown in thiosulate or thiosulfate-glucose medium eliminates the ED pathway as a significant route of glucose catabolism in T.concretivorus. These results suggest that pentose shunt pathway performs an energetic role in glucose metabolism by T.concretivorus with EMP as a subway. The absence of ED pathway and the presence of pentose shunt pathway which is the major route of catabolism in T.concretivorus are similar to those of other obligately chemolitho-trophic thiobacilli. The G-6-P and 6-PG dehydrogenase are both NAD and NADP specific, but MAD predominant. However, the 3-PGAL dehydrogenase is only NAD specific. Since the specific activity of 3-PGAL generated from glucose is converted mainly into pyruvate which is channeled into the TCA cycle. All enzymes of the TCA cycle tested and NADH oxidase are detected in the cells of T.concretivorus grown in thiosulfate. The specific activities of fumarase and isocitrate dehydrogenase are high and others are low. The presence of two isocitrate dehydrogenase (NAD-and NADP-linked) may have important regulatory function for this organism. The activity of NAD-oxidase, which is implicated in the energy generating metabolism, was very high in the crude cell-free extract of T.concretivorus, recording 55.11 m.mu. mole/min/mg protein. This well coincides with the fact that activities of NAD-linked G-6-P dehydrogenase, 6-PG dehydrogenase and 3-PGAL dehydrogenase were high.