• The Korean Journal of Physiology
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• 제24권2호
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• pp.331-344
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• 1990

What makes glucose transport function sensitive to insulin in one cell type such as adipocyte, and insensitive in another such as liver cells is unresolved question at this time. Recently it is known that insulin stimulates glucose transport in adipocytes largely by redistributing transporter from the storage pool that is included in a low density microsomal fraction to plasma membrane. Therefore, insulin sensitivity may depend upon the relative distribution of gluscose transporters between the plasma membrane and in an intracellular storage compartment. In hepatocytes, the subcellular distribution of glucose transporter is less well documented. It is thus possible that the apparent insensitivity of the hepatocyte system could be either due to lack of the constitutively maintained, intracellular storage pool of glucose transporter or lack of insulin-mediated transporter translocation mechanism in this cell. In this study, I examined if any intracellular glucose transporter pool exists in hepatocytes and this pool is affected by insulin. The results obtained summarized as followings: 1) Distribution of subcellular fractions of hepatocyte showed that there are $24.9{\pm}1.3%$ of plasma membrane, $36.9{\pm}1.7%$ of nucleus-mitochondria enriched fraction, $23.5{\pm}1.2%$ of lysosomal fraction, $9.6{\pm}1.0%$ of high density microsomal fraction and $4.9{\pm}0.5%$ of low density microsomal fraction. 2) In adipocyte, there were $29.9{\pm}2.6%$ of plasma membrane, $19.4{\pm}1.9%$ of nucleus-mitochondria enriched fraction, $26.7{\pm}1.8%$ of high density microsomal fraction and $23.9{\pm}2.1%$ of low density microsomal fraction. 3) Surface labelling of sodium borohydride revealed that plasma membrane contaminated to lysosomal fraction by $26.8{\pm}2.8%$, high density microsomal fraction by $8.3{\pm}1.3%$ and low density microsomal fraction by $1.7{\pm}0.4%$ respectively. 4) Cytochalasin B bound to all of subcellular fractions with a Kd of $1.0{\times}10^{-6}M$. 5) Photolabelling of cytochalasin B to subcellular fractions occurred on 45 K dalton protein band, a putative glucose transporter and D-glucose inhibited the photolabelling. 6) Insulin didn't affect on the distribution of subcellular fractions and translocation of intracellular glucose transporters of hepatocytes. 7) HEGT reconstituted into hepatocytes was largely associated with plasma membrane and very little was found in low density microsomal fraction which equals to the native glucose transporter distribution. Insulin didn't affect on the distribution of exogeneous glucose transporter in hepatocytes. From the above results it is concluded that insulin insensitivity of hepatocyte may due to lack of intracellular storage pool of glucose transporter and thus intracellular storage pool of glucose transporter is an essential feature of the insulin action.

• Pediatric Infection and Vaccine
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• 제24권2호
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• pp.102-107
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• 2017

목적: 가와사키병의 환아뿐만 아니라, 다른 전신 염증 질병의 환아들에 관상동맥 병변(coronary arterial lesion [CAL])의 발생이 보고되었다. 본 연구에서는 전형적인 전신염증반응증후군(systemic inflammatory response syndrome [SIRS])의 소견을 보이는 패혈증 마우스 모델에서 가와사키병 환아에게 관찰되는 CAL이 발생하는지 확인하고자 하였다. 방법: 생후 6주 C57BL/6 마우스에 내독소를 복강내주사하여 SIRS를 보이는 패혈증 모델을 유도하였다. 대조군과 패혈증군의 주요 장기의 조직학적 소견을 비교하였고 패혈증 마우스에서 CAL을 찾기 위한 시도를 하였다. 결과: 대조군과 비교하여, 염증세포의 침윤이 패혈증 마우스의 심장, 간, 신장에 상대적으로 증가하였다. 패혈증 마우스의 심장에서 심근(심근염)과 심장 주위 연조직에 림프구 침윤을 확인하였다. 또한, 패혈증 마우스의 관상동맥을 관찰하였지만, CAL을 확인할 수는 없었다. 결론: 본 연구에서 패혈증 마우스 모델에서 CAL의 존재를 확인하는 것은 실패하였다. 하지만, SIRS를 유발하는 많은 종류의 원인 질병에서 CAL이 발생한다는 것은 잘 알려져 있다. 가와사키병을 포함한 다양한 전신 염증 질병에 나타나는 CAL의 임상적 의미에 대한 연구가 필요할 것이다.

• Molecules and Cells
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• 제37권1호
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• pp.74-80
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• 2014

The peroxisome is an intracellular organelle that responds dynamically to environmental changes. Various model organisms have been used to study the roles of peroxisomal proteins in maintaining cellular homeostasis. By taking advantage of the zebrafish model whose early stage of embryogenesis is dependent on yolk components, we examined the developmental roles of the D-bifunctional protein (Dbp), an essential enzyme in the peroxisomal ${\beta}$-oxidation. The knockdown of dbp in zebrafish phenocopied clinical manifestations of its deficiency in human, including defective craniofacial morphogenesis, growth retardation, and abnormal neuronal development. Overexpression of murine Dbp rescued the morphological phenotypes induced by dbp knockdown, indicative of conserved roles of Dbp during zebrafish and mammalian development. Knockdown of dbp impaired normal development of blood, blood vessels, and most strikingly, endoderm-derived organs including the liver and pancreas - a phenotype not reported elsewhere in connection with peroxisome dysfunction. Taken together, our results demonstrate for the first time that zebrafish might be a useful model animal to study the role of peroxisomes during vertebrate development.

• 한국식품영양과학회지
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• 제33권5호
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• pp.778-784
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• 2004

인삼을 재배한 후 널리 이용되지 못하고 있는 잎, 줄기 등 인삼 부산물의 활용방안을 모색하고자 연구를 수행하였다. 이에 따라 인삼잎과 줄기를 혼합하여 추출한 추출물을 대상으로 일반 영양성분 함량, 무기질 함량, 아미노산 및 지방산 조성을 분석하고 세포독성에 미치는 영향을 조사하여 다음과 같은 결과를 얻었다. 인삼잎, 줄기 혼합 추출물의 수분함량은 96.61%, 탄수화물 2.51%, 조회분 0.53%, 조지방 0.20% 및 조단백질이 0.15%이었다. 무기질 중 칼륨함량이 102.56 mg/100 g으로 가장 높았고 그 외 칼슘, 마그네슘, 나트륨, 인 및 철분, 망간, 아연, 구리도 함유되어 있었다. Glutamic acid와 aspartic acid 등 산성아미노산 함량이 높게 나타났고 필수아미노산이 모두 함유되어 있었다. 또한 불포화지방산 함량은 56.52%이었고 palmitic acid 함량이 39.99%로 가장 높았고, linoleic acid 14.96%, docosatetranoic acid 13.31%, linolenic acid 12.19%의 순이었다. 인삼의 총 ginenoside 함량은 0.82 mg/mL이 었고 PD/PT 함유 비율은 0.68이었다. 정상적인 간과 신장 세포의 생존율에는 negative effect를 나타내지 않았고 미토콘드리아와 라이소좀 수준에서 세포독성을 나타내지 않았다. 인삼잎, 줄기 혼합 추출물의 약리효능을 나타내는 gensenoside의 함량이 0.82 mg/mL로서 비교적 소량 함유되어 있으나 인삼 부산물의 활용차원에서 동물의 사료나 기능성 식품 재료로의 사용은 가능할 것으로 생각된다. 향후 동물실험 및 임상실험을 이용한 기능성 평가를 통해 확실하고 구체적인 활용방안의 모색이 요구되어진다.

• 대한임상독성학회지
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• 제17권2호
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• pp.58-65
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• 2019

Purpose: Alpha-amanitin induces potent oxidative stress and apoptosis, and may play a significant role in the pathogenesis of hepatotoxicity. This study examined the mechanisms of α-amanitin-induced apoptosis in vitro, and whether green tea extract (GTE) offers protection against hepatic damage caused by α-amanitin (AMA) induced apoptosis in vivo. Methods: The effects of GTE and SIL on the cell viability of cultured murine hepatocytes induced by AMA were evaluated using an MTT assay. Apoptosis was assessed by an analysis of DNA fragmentation and caspase-3. In the in vivo protocol, mice were divided into the following four groups: control group (0.9% saline injection), AMA group (α-amanitin 0.6 mg/kg), AMA+SIL group (α-amanitin and silibinin 50 mg/kg), and AMA+GTE group (α-amanitin and green tea extract 25 mg/kg). After 48 hours of treatment, the hepatic aminotransferase and the extent of hepatonecrosis of each subject was evaluated. Results: In the hepatocytes exposed to AMA and the tested antidotes, the cell viability was significantly lower than the AMA only group. An analysis of DNA fragmentation showed distinctive cleavage of hepatocyte nuclear DNA in the cells exposed to AMA. In addition, the AMA and GTE or SIL groups showed more relief of the cleavage of the nuclear DNA ladder. Similarly, values of caspase-3 in the AMA+GTE and AMA+SIL groups were significantly lower than in the AMA group. The serum AST and ALT levels were significantly higher in the AMA group than in the control and significantly lower in the AMA+GTE group. In addition, AMA+GTE induced a significant decrease in hepatonecrosis compared to the controls when a histologic grading scale was used. Conclusion: GTE is effective against AMA-induced hepatotoxicity with its apoptosis regulatory properties under in vitro and in vivo conditions.

• Journal of Applied Biological Chemistry
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• 제64권3호
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• pp.291-298
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• 2021

본 연구에서는 고지방식이(HFD)를 급식하여 제조한 비만마우스 모델을 사용하여 berberine (BBR)과 silibinin (SBN) 복합투여가 혈중 지질대사 및 항비만 개선 효능에 유의적인 시너지 효과가 있는지 조사하였다. HFD로 유도된 비만마우스를 8 주 동안 HFD의 지속적인 제공와 함께 BBR 및 SBN (BBR-SBN) 조합을 투여하였다. 실험이 진행되는 동안 체중과 식이량을 측정하였고 혈중 총 콜레스테롤, 중성지방 및 HDL 콜레스테롤 수준을 분석하였다. HFD를 제공한 마우스는 정상 대조군(NC) 그룹에 비해 체중과 총 콜레스테롤 및 중성지방 수치가 급격히 증가했다. 그러나 이러한 비만마우스에 BBR-SBN조합을 투여하였을 때 체중 증가가 현저하게 감소하였고 HDL 콜레스테롤 수치가 증가하였으며 총 콜레스테롤 및 중성지방 수치는 유의하게 억제되었다. HFD그룹의 복부지방 무게는 유의하게 증가했으며 부고환 지방조직 내의 지방세포의 크기가 NC 그룹에 비해 크게 확장된 것으로 나타났다. 그러나 BBR-SBN 그룹에서는 지방세포의 크기가 NC 그룹의 크기와 비슷했으며 복부지방 무게가 현저하게 감소하였다. 더불어, HFD 그룹에서 보이는 간 조직의 거대 소포성 지방구의 축적은 BBR-SBN 그룹에서 크게 감소되었다. 이러한 결과는 BBR-SBN 조합이 HFD 유발 비만마우스에서 체중 및 복부 지방 증가를 현저하게 감소시키는 경향이 있으며 혈청 내의 총 콜레스테롤 및 중성지방 수준을 낮추어 항비만 효능을 개선시킬 수 있는 가능성을 보여주는 것으로 앞으로 항비만 치료 및 개선제제로서의 잠재력을 가지고 있음을 시사한다.

• 생명과학회지
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• 제31권9호
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• pp.796-805
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• 2021

간 소포체(ER) 스트레스는 비알콜성지방간과 인슐린 저항성의 발달에 기여하고, unfolded protein response(UPR)의 구성요소는 지질 대사를 조절한다. 최근 연구에 따르면 ER 스트레스와 비정상적인 세포 지질 대사 사이의 연관성이 보고되었으며, 이 과정에서 지질 대사의 중심 조절자인 sterol regulatory element binding proteins(SREBPs)의 관련성이 확인되었다. 그러나 ER 스트레스 동안 지질 대사를 조절하는 SREBP의 정확한 역할과 비알콜성지방간에 대한 기여는 아직 밝혀지지 않았다. 본 연구에서 SREBP-1c 결핍은 UPR, 염증 및 지방산 산화 조절을 통해 ER 스트레스에 의해 유도된 비알콜성지방간으로부터 생쥐를 보호한다는 것을 보여준다. SREBP-1c는 inositol requiring kinase 1α (IRE1α) 발현을 직접적으로 조절하고 ER 스트레스에 의해 유도된 tumor necrosis factor-α의 활성화를 매개하여 peroxisome proliferator-activated receptor γ coactivator 1-α (PGC1α)의 감소와 그에 따른 지방산 산화의 장애를 유발한다. 그러나, SREBP-1c의 유전적 결핍은 이러한 현상을 보호하여 간 염증과 지방 축적을 완화시킨다. SREBP-1c 결핍이 ER 스트레스에 의해 유도된 염증 신호를 방지하는 메커니즘은 아직 밝혀지지 않았지만, SREBP-1c가 결핍된 Kupffer 세포에서 IRE1α 신호의 변화가 염증 신호에 관여할 수 있을 것으로 생각된다. 본 연구결과는 SREBP-1c가 ER 스트레스에 의해 유도된 비알콜성지방간에서 UPR 및 염증의 조절에 중요한 역할을 함을 시사한다.

• Toxicological Research
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• 제35권1호
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• pp.45-63
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• 2019

In view of the growing industrial use of Bacterial cellulose (BC), and taking into account that it might become airborne and be inhaled after industrial processing, assessing its potential pulmonary toxic effects assumes high relevance. In this work, the murine model was used to assess the effects of exposure to respirable BC nanofibrils (nBC), obtained by disintegration of BC produced by Komagataeibacter hansenii. Murine bone marrow-derived macrophages ($BMM{\Phi}$) were treated with different doses of nBC (0.02 and 0.2 mg/mL, respectively 1 and $10{\mu}g$ of fibrils) in absence or presence of 0.2% Carboxymethyl Cellulose (nBCMC). Furthermore, mice were instilled intratracheally with nBC or nBCMC at different concentrations and at different time-points and analyzed up to 6 months after treatments. Microcrystaline $Avicel-plus^{(R)}$ CM 2159, a plant-derived cellulose, was used for comparison. Markers of cellular damage (lactate dehydrogenase release and total protein) and oxidative stress (hydrogen peroxidase, reduced glutathione, lipid peroxidation and glutathione peroxidase activity) as well presence of inflammatory cells were evaluated in brochoalveolar lavage (BAL) fluids. Histological analysis of lungs, heart and liver tissues was also performed. BAL analysis showed that exposure to nBCMC or CMC did not induce major alterations in the assessed markers of cell damage, oxidative stress or inflammatory cell numbers in BAL fluid over time, even following cumulative treatments. $Avicel-plus^{(R)}$ CM 2159 significantly increased LDH release, detected 3 months after 4 weekly administrations. However, histological results revealed a chronic inflammatory response and tissue alterations, being hypertrophy of pulmonary arteries (observed 3 months after nBCMC treatment) of particular concern. These histological alterations remained after 6 months in animals treated with nBC, possibly due to foreign body reaction and the organism's inability to remove the fibers. Overall, despite being a safe and biocompatible biomaterial, BC-derived nanofibrils inhalation may lead to lung pathology and pose significant health risks.

• 대한방사성의약품학회지
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• 제5권1호
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• pp.18-25
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• 2019

2-Nitroimidazole derivatives have been reported to accumulate in hypoxic tissue. We prepared a novel $^{99m}Tc-MAG_3$-2-nitroimidazole and evaluated the feasibility for hypoxia imaging agent. $Bz-MAG_3$-2-nitroimidazole was synthesized by direct coupling of $Bz-MAG_3$ and 2-nitroimidazole using dicyclohexylcarbodiimide. $Bz-MAG_3$-2-nitroimidazole was labeled with $^{99m}Tc$ in the presence of tartaric acid and $SnCl_2-2H_2O$ at $100^{\circ}C$ for 30 min. And the reaction mixture was purified by $C_{18}$ Sep-pak cartridge. The labeling efficiency and the radiochemical purity were checked by ITLC-SG/acetonitrile. The tumor was grown in balb/c mice for 8~13 days after the subcutaneous injection of tumor cells, CT-26 (murine colon adenocarcinoma cell). Biodistribution study and tumor autoradiography were performed in the xenografted mice after i.v injection of 74 kBq/0.1 mL and 19 MBq/0.1 mL of $^{99m}Tc-MAG_3$-2-nitroimidazole, respectively. In vivo images of $^{99m}Tc-MAG_3$-2-nitroimidazole in tumor bearing mice were obtained 1.5 hr post injection. The labeling efficiency was $45{\pm}20%$ and the radiochemical purity after purification was over 95%. Paper electrophoresis confirmed negative charge of $^{99m}Tc-MAG_3$-2-nitroimidazole. $^{99m}Tc-MAG_3$-2-nitroimidazole was very stable at room temperature and its protein binding was 53%. The $^{99m}Tc-MAG_3$-2-nitroimidazole exhibited high uptake in the liver, stomach and intestine. In biodistribution study using tumor bearing mice, the uptakes (% ID/g) of the tumor were $0.5{\pm}0.1$, $0.4{\pm}0.0$, $0.2{\pm}0.1$ and $0.1{\pm}0.1$ at 5, 15, 30 min and 4 hrs. Tumor/muscle ratio were $1.4{\pm}0.1$, $2.2{\pm}0.83$, $3.0{\pm}0.9$, and 3.7 (n=2) for 5, 15, 30 min and 4 hrs. The uptake in hypoxic area was found higher than in non-hypoxic area of tumor tissue by autoradiography. In vivo images showed the relatively faint uptake to the hypoxic tumor region. $^{99m}Tc-MAG_3$-2-nitroimidazole was successfully synthesized and found feasible for imaging hypoxia.

• 한방비만학회지
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• 제18권2호
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• pp.106-114
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• 2018

Objectives: We investigated about the microbial properties and changes in the efficacy of the Codonopsis lanceolata (CL) by natural fermentation. Methods: CL was fermented for four weeks in a well-ventilated place with 2.5% salt. pH, total sugar, total polyphenol, and total flavonoid were measured to determine fermentation characteristics according to fermentation period and salt treatment. Polymerase chain reaction denaturing gradient gel electrophoresis and random amplification of polymorphic DNA-polymerase chain reaction were carried out for microbial analysis during fermentation. In addition, HepG2 cell was cultured to check the lipid accumulation through oil red O staining and the glucose uptake was analyzed by measuring the 2-NBDG at C2C12 cell. Results: The pH level and the total sugar decreased with the CL fermentation. Total polyphenol and flavonoid increased after CL fermentation. It was confirmed that Leuconostoc mesenteroides were maintained continuously during fermentation. In the salt treatment CL, there was a sharp increase in Rahnella aquatilis. Lactobacillus plantarum matrix was observed in fermented CL. In addition, Lactococcus lactis, Weissella koreensis, R. aquatilis, L. plantarum, Leu. mesenteroides have been added to the salt treatment. Glucose uptake were significantly increased after fermentation with salt for four weeks. Lipid accumulation in the HepG2 cells was observed that there was difference (P<0.01) between free fatty acid group (100%) and decreased 4 weeks after fermentation (90.38%) at $800{\mu}g/mL$. Conclusions: Total polyphenol and flavonoid were increased after CL fermentation. Especially, percentage of the glucose uptake and lipid accumulation inhibition increased in CL fermentation with salt. It is expected that fermentation of salt treated CL will be more effective in diabetes and fatty liver.