• Asian-Australasian Journal of Animal Sciences
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• 제32권7호
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• pp.922-929
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• 2019

Objective: Mutations in low-density lipoprotein receptor (LDLR), which encodes a critical protein for cholesterol homeostasis and lipid metabolism in mammals, are involved in cardiometabolic diseases, such as familial hypercholesterolemia in pigs. Whereas microRNAs (miRNAs) can control LDLR regulation, their involvement in circulating cholesterol and lipid levels with respect to cardiometabolic diseases in pigs is unclear. We aimed to identify and analyze LDLR as a potential target gene of SSC-miR-20a. Methods: Bioinformatic analysis predicted that porcine LDLR is a target of SSC-miR-20a. Wild-type and mutant LDLR 3'-untranslated region (UTR) fragments were generated by polymerase chain reaction (PCR) and cloned into the pGL3-Control vector to construct pGL3 Control LDLR wild-3'-UTR and pGL3 Control LDLR mutant-3'-UTR recombinant plasmids, respectively. An miR-20a expression plasmid was constructed by inserting the porcine premiR-20a-coding sequence between the HindIII and BamHI sites in pMR-mCherry, and constructs were confirmed by sequencing. HEK293T cells were co-transfected with the miR-20a expression or pMR-mCherry control plasmids and constructs harboring the corresponding 3'-UTR, and relative luciferase activity was determined. The relative expression levels of miR-20a and LDLR mRNA and their correlation in terms of expression levels in porcine liver tissue were analyzed using reverse-transcription quantitative PCR. Results: Gel electrophoresis and sequencing showed that target gene fragments were successfully cloned, and the three recombinant vectors were successfully constructed. Compared to pMR-mCherry, the miR-20a expression vector significantly inhibited wild-type LDLR3'-UTR-driven (p<0.01), but not mutant LDLR-3'-UTR-driven (p>0.05), luciferase reporter activity. Further, miR-20a and LDLR were expressed at relatively high levels in porcine liver tissues. Pearson correlation analysis revealed that porcine liver miR-20a and LDLR levels were significantly negatively correlated (r = -0.656, p<0.05). Conclusion: LDLR is a potential target of miR-20a, which might directly bind the LDLR 3'-UTR to post-transcriptionally inhibit expression. These results have implications in understanding the pathogenesis and progression of porcine cardiovascular diseases.

• Reproductive and Developmental Biology
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• 제29권1호
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• pp.19-24
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• 2005

저밀도 리포단백질 수용체 관련 단백질 5(LRP5)는 간과 췌장을 포함하여 많은 조직에서 발현하며 아포리포단백질 E와 결합한다. 이와 같은 LRP5 유전자의 체내 기능을 규명하기 위하여 LRP5 유전자가 결손된 생쥐를 개발하였다. 먼지 LRP5 genomic DNA는 TT2 ES 세포로부터 분리하였으며 LRP5 유전자의 엑손 18에 neo 유전자를 삽입한 vector를 구축하고 TT2 ES 세포에 도입하였다. 178개의 G418 내성을 보인 세포 중 상동유전자 재조합에 의하여 targeting vector가 LRP5 유전자 위치에 삽입된 clone은 3개였다. 키메라 생쥐는 상실배기 수정을 ES 세포와 응집시켜 생산하였으며 생산된 키메라 생쥐는 C57BL/6 생쥐와 교미를 유도하여 heterozygous를 얻었다. 또한 이들 heterozygous간의 교배에 의하여 LRP5 유전자 결손 생쥐를 생산하였다. 이러한 생쥐는 LRP5 유전자의 체내 기능연구에 있어서 모델로 이용될 것으로 생각된다.

• Nutrition Research and Practice
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• 제11권6호
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• pp.445-451
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• 2017

BACKGROUND/OBJECTIVES: Endoplasmic reticulum (ER) stress is positively associated with atherosclerosis via elevating macrophage cell death and plaque formation, in which oxidative stress plays a pivotal role. Antioxidative, lipid-lowering, and anti-atherogenic effects of kimchi, a Korean fermented vegetable, have been established, wherein capsaicin, ascorbic acid, quercetin, 3-(4'-hydroxyl-3',5'-dimethoxyphenyl)propionic acid, and lactic acids were identified. In this study, mechanisms of action of kimchi methanol extracts (KME) on fatty streak formation via suppression of ER stress and apoptosis in aorta were examined in low-density lipoprotein receptor knockout mice. MATERIALS AND METHODS: Mice fed a high cholesterol diet with an oral administration of KME (KME group, $200 mg{\cdot}kg-bw^{-1}{\cdot}day^{-1}$) or distilled water (control group) for 8 weeks (n = 20 for group). Plasma lipid and oxidative stress levels were evaluated. Protein expression was measured by western blot assay. Fatty streak lesion size and the degree of apoptosis were examined in the aorta. RESULTS: Compared to the control group, in the KME group, plasma lipids levels were decreased and oxidative stress was alleviated (P < 0.05). Protein expression levels of nuclear factor (erythroid-derived 2)-like 2-mediated antioxidants in aorta were increased whereas those for ER stress markers, glucose regulated protein 78, phospho-protein kinase RNA-like ER kinase, phospho-eukaryotic initiation factor 2 subunit ${\alpha}$, X-box binding protein 1, and C/EBP homologous protein were decreased in the KME group (P < 0.05). Moreover, apoptosis was suppressed via downregulation of phospho-c-Jun N-terminal kinase, bcl-2-associated X protein, caspases-9, and -3 with a concomitant upregulation of anti-apoptotic protein, B-cell lymphoma 2 (P < 0.05). Fatty streak lesion size was reduced and the degree of apoptosis was less severe in the KME group (P < 0.05). CONCLUSIONS: In conclusion, antioxidant activity of KME might prevent fatty streak formation through, in part, inhibition of ER stress and apoptosis in aortic sinus where macrophages are harbored.

• 동의생리병리학회지
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• 제36권5호
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• pp.181-186
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• 2022

Atractylodes macrocephala (AM) and Amomum villosum (AV) are the most common herbs in Korean Medicine to treat digestive diseases. In this study, we investigated the cholesterol lowering effects of mixtures of AM and AV extracts on high cholesterol diet (HCD) induced dyslipidemia mouse model. We classified animals into six different groups; Group 1: Normal diet, Group 2: HCD, Group 3: AV extracts : AM extracts (1:1) (200 mg/kg) + HCD, Group 4: AV extracts : AM extracts (1:2) (200 mg/kg) + HCD, Group 5: AV extracts : AM extracts (1:3) (200 mg/kg) + HCD, Group 6: Simvastatin 40 mg/kg + HCD. After 4 weeks of oral administration of respective drugs, we checked body, liver and epididymal fatweights along with liver and serum triacylglyceride (TG) concentration, total and low density lipoprotein (LDL) cholesterol in serum. Moreover, 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase (HMGCR), LDL receptor (LDLR), and sterol regulatory element-binding protein 2 (SREBP2) were detected by RT PCR or western blot analysis. The overall results showed that mixtures of AM and AV extracts inhibited HCD-induced increases of total cholesterol and LDL cholesterol in serum. Those effects seem to be caused by AM and AV extracts through inhibition of HMGCR expression. And thus blood cholesterol is induced into the liver by increasing LDLR expression, which is regulated by SREBP2 transcrption factor. The cholesterol lowering effects and mechanism of mixtures of AM and AV extracts was similar to the statin. We have identified the potential mixtures of AM and AV extracts as a new treatment for dyslipidemia.

• Journal of Ginseng Research
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• 제28권2호
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• pp.87-93
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• 2004

인삼성분 중 ginsenoside-Rb$_2$에 의한 LDL receptor발현 증가의 기전을 HepG$_2$세포에서 관찰하였고 이를 lovastatin과 비교하였다. 콜레스테롤 투여에 의하여 억제된 LDL receptor mRNA발현이 ginsenoside-Rb$_2$에 의하여 다시 증가하였고 이는 lovastatin에 의한 증가 효과보다 뛰어났다. SREBP mRNA의 발현 또한 콜레스테롤 투여에 의하여 억제되나 ginseonside-Rb$_2$에 의하여 발현이 증가하였고 이는 lovastatin에 의한 효과와 비슷하였다. 세포에 투여한 ginsenoside-Rb$_2$의 농도에 비례하여 SREBP-1 mRNA의 발현이 증가하였으며 ginsenoside-Rb$_2$의 대사체인 compound K를 투여한 경우에도 SREBP-1 mRNA가 비슷한 양상으로 혹은 더 많이 발현되었다. 따라서 ginsenoside-Rb$_2$에 의한 LDL receptor의 발현 증가는 SREBP의 발현 증가 때문이라고 설명할 수 있다. 즉 ginsenoside-Rb$_2$에 의한 SREBP 발현 증가는 콜레스테롤 투여에 의하여 억제된 LDL receptor발현을 증가시켜 결과적으로 혈중의 콜레스테롤을 효과적으로 제거하는 것으로 판단된다.

• Animal Bioscience
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• 제35권8호
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• pp.1184-1194
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• 2022

Objective: High concentrate diets are widely used to satisfy high-yielding dairy cows; however, long-term feeding of high concentrate diets can cause subacute ruminal acidosis (SARA). The endocrine disturbance is one of the important reasons for metabolic disorders caused by SARA. However, there is no current report about thyroid hormones involved in liver metabolic disorders induced by a high concentrate diet. Methods: In this study, 12 mid-lactating dairy cows were randomly assigned to HC (high concentrate) group (60% concentrate of dry matter, n = 6) and LC (low concentrate) group (40% concentrate of dry matter, n = 6). All cows were slaughtered on the 21st day, and the samples of blood and liver were collected to analyze the blood biochemistry, histological changes, thyroid hormones, and the expression of genes and proteins. Results: Compared with LC group, HC group showed decreased serum triglyceride, free fatty acid, total cholesterol, low-density lipoprotein cholesterol, increased hepatic glycogen, and glucose. For glucose metabolism, the gene and protein expression of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase 1 in the liver were significantly up-regulated in HC group. For lipid metabolism, the expression of sterol regulatory element-binding protein 1, long-chain acyl-CoA synthetase 1, and fatty acid synthase in the liver was decreased in HC group, whereas carnitine palmitoyltransferase 1α and peroxisome proliferator activated receptor α were increased. Serum triiodothyronine, thyroxin, free triiodothyronine (FT3), and hepatic FT3 increased in HC group, accompanied by increased expression of thyroid hormone receptor (THR) in the liver. Conclusion: Taken together, thyroid hormones may increase hepatic gluconeogenesis, β-oxidation and reduce fatty acid synthesis through the THR pathway to participate in the metabolic disorders caused by a high concentrate diet.

• Nutrition Research and Practice
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• 제14권3호
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• pp.175-187
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• 2020

BACKGROUND/OBJECTIVES: In this study, we investigated the beneficial effects of skate cartilage extracts containing chondroitin sulfate (SCS) on hyperlipidemia-induced inflammation and oxidative stress in high cholesterol diet (HCD)-fed mice in comparison with the effects of shark cartilage-derived chondroitin sulfate (CS). MATERIALS/METHODS: Low-density lipoprotein receptor knockout (LDLR-KO) mice were fed HCD with an oral administration of CS (50 and 100 mg/kg BW/day), SCS (100 and 200 mg/kg BW/day), or water, respectively, for ten weeks. RESULTS: The administration of CS or SCS reduced the levels of serum triglyceride (TG), total cholesterol (TC), and LDL cholesterol and elevated the levels of high-density lipoprotein cholesterol, compared with those of the control group (P < 0.05). Furthermore, CS or SCS significantly attenuated inflammation by reducing the serum levels of interleukin (IL)-1β and hepatic protein expression levels of nuclear factor kappa B, inducible nitric oxide synthase, cyclooxygenase-2, and IL-1beta (P < 0.05). In particular, the serum level of tumor necrosis factor-alpha was reduced only in the 100 mg/kg BW/day of SCS-fed group, whereas the IL-6 level was reduced in the 100 and 200 mg/kg BW/day of SCS-fed groups (P < 0.05). In addition, lipid peroxidation and nitric oxide production were attenuated in the livers of the CS and SCS groups mediated by the upregulation of hepatic proteins of antioxidant enzymes, such as superoxide dismutase, catalase, and glutathione peroxidase (P < 0.05). CONCLUSIONS: These results suggest that the biological effects of SCS, similar to those of CS, are attributed to improved lipid profiles as well as suppressed inflammation and oxidative stress induced by the intake of HCD.

• 한국식품과학회지
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• 제47권3호
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• pp.364-372
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• 2015

이 연구는 고지방 고콜레스테롤 식이를 12주 동안 랫트에게 공급하여 복분자와 홍삼, 복분자와 홍삼 발효 추출물의 지질대사 및 비만 개선효과를 조사하였다. 정상식이, 고지방 고콜레스테롤 식이, 양성대조군, 유산균발효군, 복분자와 홍삼, 복분자와 홍삼 발효 추출물 투여군의 체중증가, 음수, 식이 섭취량은 그룹간의 유의적인 차이를 보이지 않았다. 하지만 혈중 HDL-콜레스테롤은 고지방 고콜레스테롤 식이와 비교 했을 때 복분자와 홍삼 발효 추출물에서 유의적인 증가를 보였으며, LDL-콜레스테롤, 중성지방은 유의적인 감소율을 보였다. 또한, 간 조직에서 복분자와 홍삼 발효추출물 처치에 의해 HMG-CoA reductase, LDL receptor 및 SREBP-2 mRNA의 발현 증가와 지방생성 억제를 확인하였다. 그리고 복분자와 홍삼 발효 추출물 투여군은 비만인자인 혈중 leptin과 FAS의 농도를 유의적으로 감소시켰을 뿐만 아니라 대변에서 체내 콜레스테롤 배출을 증가시켰다. 이러한 결과로 미루어 보아 복분자와 홍삼 발효 추출물은 혈중 지질 대사 및 비만의 예방에 기여할 것으로 판단된다.

• Toxicological Research
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• 제19권3호
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• pp.205-210
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• 2003

The aim of this study was to estimate the influence of 37 bp insertion/deletion (I/O) poly-morphism of the low density lipoprotein receptor-related protein-associated protein 1 (LRPAP1) gene on anthropometrical or biochemical parameters in korean general population. To determine the frequency of the genotype, we analyzed 244 samples of Korean origin. The frequency of the I allele was 0.55 in men and 0.56 in women, which were significantly higher than the frequency (0.26) that was reported in Czech population of Caucasian origin. In addition, the I allele of this polymorphism was significantly associated with higher value of body mass index (BMI) in our subjects by ANOVA test (P<0.05), and this association was maintained after controlling for age and gender by ANCOVA test (P<0.05). Thus, our results suggest that the I/O polymorphism of the LRPAP1 gene may be useful as a genetic marker for obesity in Korean general population.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.372.1-372.1
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• 2016

Recently, there are a lot of diseases all around the world. Out of them, Atherosclerosis (AS) is the most common cause of stroke, cardiovascular mortality, and myocardial infarction. The macrophage-derived foam cell, which is formed by oxidized low-density lipoprotein (oxLDL), is the crucial marker for AS. In this study, we report a label-free capacitance imaging technique with multi-electrode array (MEA). The lipid-rich aorta arch lesions, which are derived from an apolipoprotein-E receptor-deficient (apoE-/-) mouse, exhibit higher capacitance than the lipid-free aorta arch, allowing the capacitance imaging of lipid region in atherosclerosis. To improve the contacts between MEA and tissue, polypyrrole(PPy)-coated multi walled carbon nanotubes (MWNTs) multi electrode array (PPy-MWNTs-MEA) was fabricated. Compared to TiN-MEA, PPy-MWNTs-MEA yielded lower contact impedance and better capacitance images. In addition, we have also developed a flexible MEA using single walled carbon nanotubes on a PET substrate. The lipid region could be discriminated in the capacitance images of the lipid-rich aorta arch lesions measured using flexible MEA, demonstrating a feasibility of in vivo applications.