• 제목/요약/키워드: LDL-receptor

검색결과 121건 처리시간 0.026초

Inhibition of Atherosclerotic Lesion by KR-31378 in LDL Receptor Null Mice

  • Kim, Jiyun;Nam, Ki-Hoan;Choi, Jae-Hoon;Kim, Hyoung-Chin;Yang, Sung-Don;Kang, Joo-Hyung;Ryu, Young-Han;Kim, Eun-Young;Kim, Sun-Ok;Yoo, Sung-Eun;Oh, Goo-Taeg
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2003년도 추계학술대회
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    • pp.195-195
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    • 2003
  • The recruitment and infiltration of monocytes into the artery wall is a crucial early step in atherogenesis. KR-31378 has been shown to be a neuroprotective agent in rat brain via its potent antioxidant and antiapoptotic actions. Here, we report the effects of this compound on atherogenesis, and some possible mechanisms of action.(omitted)

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Increase of Intracellular $Ca^{2+}$ Concentration Induced by Lysophosphatidylcholine in Murine Aortic Endothelial Cells

  • Zhu, Mei-Hong;Park, Sung-Jin;Kim, Hyun-Jin;Yang, Dong-Ki;Suh, Suk-Hyo;So, In-Suk;Kim, Ki-Whan
    • The Korean Journal of Physiology and Pharmacology
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    • 제6권2호
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    • pp.93-99
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    • 2002
  • Effects of oxidized low-density lipoprotein (ox-LDL), $1-{\alpha}-stearoyl-lysophosphatidylcholine$ (LPC), on intracellular $Ca^{2+}$ concentration were examined in mouse endothelial cells by measuring intracellular $Ca^{2+}$ concentration $([Ca^{2+}]_i)$ with fura 2-AM and reverse transcription-polymerase chain reaction (RT-PCR). LPC increased $[Ca^{2+}]_i$ under the condition of 1.5 mM $[Ca^{2+}]_o$ but did not show any effect under the nominally $Ca^{2+}-free$ condition. Even after the store depletion with $30{\mu}M$ 2,5-di-tert- butylhydroquinone (BHQ) or $30{\mu}M$ ATP, LPC could still increase the $[Ca^{2+}]_i$ under the condition of 1.5 mM $[Ca^{2+}]_o.$ The time required to increase [$Ca{2+}$]i (about 1 minute) was longer than that for ATP-induced $[Ca^{2+}]_i$ increase $(10{\sim}30\;seconds).$ LPC-induced $[Ca^{2+}]_i$ increase was completely blocked by $1{\mu}M\;La^{3+}.$ Transient receptor potential channel(trpc) 4 mRNA was detected with RT-PCR. From these results, we suggest that LPC increased $[Ca^{2+}]_i$ via the increase of $Ca^{2+}$ influx through the $Ca^{2+}$ routes which exist in the plasma membrane.

Effect of Dietary Inclusion of Lactobacillus acidophilus ATCC 43121 on Cholesterol Metabolism in Rats

  • Park, Yoo-Heon;Kim, Jong-Gun;Shin, Yong-Won;Kim, Sae-Hun;Whang, Kwang-Youn
    • Journal of Microbiology and Biotechnology
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    • 제17권4호
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    • pp.655-662
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    • 2007
  • This study examined the effects of Lactobacillus acidophilus ATCC 43121 (LAB) on cholesterol metabolism in hypercholesterolemia-induced rats. Four treatment groups of rats (n=9) were fed experimental diets: normal diet, normal $diet+LAB(2{\times}10^6\;CFU/day)$, hypercholesterol diet (0.5% cholesterol, w/w), and hypercholesterol diet+LAB. Body weight, feed intake, and feed efficiency did not differ among the four groups. Supplementation with LAB reduced total serum cholesterol (25%) and VLDL+IDL+LDL cholesterol (42%) in hypercholesterol diet groups, although hepatic tissue cholesterol and lipid contents were not changed. In the normal diet group, cholesterol synthesis (HMG-CoA reductase expression), absorption (LDL receptor expression), and excretion via bile acids (cholesterol $7{\alpha}-hydroxylase$ expression) were increased by supplementation with LAB, and increased cholesterol absorption and decreased excretion were found in the hypercholesterol diet group. Total fecal acid sterols excretion was increased by supplementation with LAB. With proportional changes in both normal and hypercholesterol diet groups, primary bile acids (cholic and chenodeoxycholic acids) were reduced, and secondary bile acids (deoxycholic and lithocholic acids) were increased. Fecal neutral sterol excretion was not changed by LAB. In this experiment, the increase in insoluble bile acid (lithocholic acid) reduced blood cholesterol level in rats fed hypercholesterol diets supplemented with LAB. Thus, in the rat, L. acidophilus ATCC 43121 is more likely to affect deconjugation and dehydroxylation during cholesterol metabolism than the assimilation of cholesterol into cell membranes.

Cryptotanshinone inhibits TNF-α-induced LOX-1 expression by suppressing reactive oxygen species (ROS) formation in endothelial cells

  • Ran, Xiaoli;Zhao, Wenwen;Li, Wenping;Shi, Jingshan;Chen, Xiuping
    • The Korean Journal of Physiology and Pharmacology
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    • 제20권4호
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    • pp.347-355
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    • 2016
  • Cryptotanshinone (CPT) is a natural compound isolated from traditional Chinese medicine Salvia miltiorrhiza Bunge. In the present study, the regulatory effect and potential mechanisms of CPT on tumor necrosis factor alpha ($TNF-{\alpha}$) induced lectin-like receptor for oxidized low density lipoprotein (LOX-1) were investigated. Human umbilical vein endothelial cells (HUVECs) were cultured and the effect of $TNF-{\alpha}$ on LOX-1 expression at mRNA and protein levels was determined by Real-time PCR and Western blotting respectively. The formation of intracellular ROS was determined with fluorescence probe $CM-DCFH_2-DA$. The endothelial ox-LDL uptake was evaluated with DiI-ox-LDL. The effect of CPT on LOX-1 expression was also evaluated with SD rats. $TNF-{\alpha}$ induced LOX-1 expression in a dose- and time- dependent manner in endothelial cells. $TNF-{\alpha}$ induced ROS formation, phosphorylation of $NF-{\kappa}B$ p65 and ERK, and LOX-1 expression, which were suppressed by rotenone, DPI, NAC, and CPT. $NF-{\kappa}B$ inhibitor BAY11-7082 and ERK inhibitor PD98059 inhibited $TNF-{\alpha}-induced$ LOX-1 expression. CPT and NAC suppressed $TNF-{\alpha}-induced$ LOX-1 expression and phosphorylation of $NF-{\kappa}B$ p65 and ERK in rat aorta. These data suggested that $TNF-{\alpha}$ induced LOX-1 expression via ROS activated $NF-{\kappa}B/ERK$ pathway, which could be inhibited by CPT. This study provides new insights for the anti-atherosclerotic effect of CPT.

Skate cartilage extracts containing chondroitin sulfate ameliorates hyperlipidemia-induced inflammation and oxidative stress in high cholesterol diet-fed LDL receptor knockout mice in comparison with shark chondroitin sulfate

  • Seol, Bo Gyeong;Kim, Ji Hyun;Woo, Minji;Song, Yeong Ok;Choi, Yung Hyun;Noh, Jeong Sook;Cho, Eun Ju
    • 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.

고지방식이 유도 비만쥐에서 이묘산의 항비만 효과 (Anti-Obesity Effects of Imyo-san on High Fat Diet Induced Obese Mice)

  • 강석범;손우석;김영준;우창훈
    • 한방재활의학과학회지
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    • 제32권2호
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    • pp.19-36
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    • 2022
  • Objectives This study is to investigate the effects and mechanisms of Imyo-san (IMS) on the obese mice model induced by high-fat diet. Methods Antioxidative capacity was measured by in vitro method. C57BL/6 mice were randomly assigned into 5 groups (n=7). Normal group was fed general diet (Normal). The other 4 groups were fed high fat diet (HFD) with water (Control), with Garcinia gummi-gutta (GG, Garcinia gummi-gutta 200 mg/kg), with low-dose IMS (IMSL, Imyo-san 0.54 g/kg) and with high-dose IMS (IMSH, Imyo-san 1.08 g/kg). Results IMS showed high radical scavenging activity. After 6 week experiment, body weight, food intake, food efficiency ratio (FER), epididymal fat and liver weight, triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, very low density lipoprotein (VLDL) cholesterol, sterol regulatory element-binding protein-1 (SREBP-1), phospho-acetyl-CoA carboxylase (p-ACC), fatty acid synthase (FAS), stearoyl-CoA desaturase-1 (SCD-1), SREBP-2, 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), phospho-liver kinase B1 (p-LKB1), phospho-AMP-activated protein kinase (p-AMPK), peroxisome proliferator-activated receptor 𝛼 (PPAR𝛼), peroxisome proliferator-activated receptor 𝛾 coactivator-1𝛼 (PGC-1𝛼), uncoupling protein-2 (UCP-2), carnitine palmitoyltransferase 1A (CPT-1A), and histology of liver and epididymal fat were measured and analysed. Body weight gain, FER, liver and epididymal fat weight of IMS groups were significantly decreased. There were significant improvements in blood lipids with less TG, TC, LDL-cholesterol, VLDL-cholesterol and more HDL-cholesterol. Proteins associated with lipid synthesis (SREBP-1, p-ACC, FAS, SCD-1) and cholesterol (SREBP-2, HMGCR) was improved. Factors regulating lipid synthesis and lipid catabolism (p-LKBI, p-AMPK, PPARα, PGC-1α, UCP-2, CPT-1A) were increased. In histological examinations, IMS group had smaller fat droplets than control group. All results increased depending on concentration. Conclusions It can be suggested that IMS has anti-obesity effects with improving lipid metabolism.

Effect of combined mulberry leaf and fruit extract on liver and skin cholesterol transporters in high fat diet-induced obese mice

  • Valacchi, Giuseppe;Belmonte, Giuseppe;Miracco, Clelia;Eo, Hyeyoon;Lim, Yunsook
    • Nutrition Research and Practice
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    • 제8권1호
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    • pp.20-26
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    • 2014
  • Obesity is an epidemic disease characterized by an increased inflammatory state and chronic oxidative stress with high levels of pro-inflammatory cytokines and lipid peroxidation. Moreover, obesity alters cholesterol metabolism with increases in low-density lipoprotein (LDL) cholesterols and triglycerides and decreases in high-density lipoprotein (HDL) cholesterols. It has been shown that mulberry leaf and fruit ameliorated hyperglycemic and hyperlipidemic conditions in obese and diabetic subjects. We hypothesized that supplementation with mulberry leaf combined with mulberry fruit (MLFE) ameliorate cholesterol transfer proteins accompanied by reduction of oxidative stress in the high fat diet induced obesity. Mice were fed control diet (CON) or high fat diet (HF) for 9 weeks. After obesity was induced, the mice were administered either the HF or the HF with combination of equal amount of mulberry leaf and fruit extract (MLFE) at 500mg/kg/day by gavage for 12 weeks. MLFE treatment ameliorated HF induced oxidative stress demonstrated by 4-hydroxynonenal (4-HNE) and modulated the expression of 2 key proteins involved in cholesterol transfer such as scavenger receptor class B type 1 (SR-B1) and ATP-binding cassette transporter A1 (ABCA1) in the HF treated animals. This effect was mainly noted in liver tissue rather than in cutaneous tissue. Collectively, this study demonstrated that MLFE treatment has beneficial effects on the modulation of high fat diet-induced oxidative stress and on the regulation of cholesterol transporters. These results suggest that MLFE might be a beneficial substance for conventional therapies to treat obesity and its complications.

FXRα Down-Regulates LXRα Signaling at the CETP Promoter via a Common Element

  • Park, Sung-Soo;Choi, Hojung;Kim, Seung-Jin;Kim, Ok Jin;Chae, Kwon-Seok;Kim, Eungseok
    • Molecules and Cells
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    • 제26권4호
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    • pp.409-414
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    • 2008
  • The cholesteryl ester transfer protein (CETP), a key player in cholesterol metabolism, has been shown to promote the transfer of triglycerides from very low density lipoprotein (VLDL) and low density lipoprotein (LDL) to high density lipoprotein (HDL) in exchange for cholesterol ester. Here we demonstrate that farnesoid X receptor ${\alpha}$ ($FXR{\alpha}$; NR1H4) down-regulates CETP expression in HepG2 cells. A $FXR{\alpha}$ ligand, chenodeoxycholic acid (CDCA), suppressed basal mRNA levels of the CETP gene in HepG2 cells in a dose-dependent manner. Using gel shift and chromatin immunoprecipitation (ChIP) assays, we found that $FXR{\alpha}$ could bind to the liver X receptor ${\alpha}$ ( $LXR{\alpha}$; NR1H3) binding site (LXRE; DR4RE) located within the CETP 5' promoter region. $FXR{\alpha}$ suppressed $LXR{\alpha}$-induced DR4RE-luciferase activity and this effect was mediated by a binding competition between $FXR{\alpha}$ and $LXR{\alpha}$ for DR4RE. Furthermore, the addition of CDCA together with a $LXR{\alpha}$ ligand, GW3965, to HepG2 cells was shown to substantially decrease mRNA levels of hepatic CETP gene, which is typically induced by GW3965. Together, our data demonstrate that $FXR{\alpha}$ down-regulates CETP gene expression via binding to the DR4RE sequence within the CETP 5' promoter and this $FXR{\alpha}$ binding is essential for $FXR{\alpha}$ inhibition of $LXR{\alpha}$-induced CETP expression.

한국인에서 peroxisome proliferator-activated receptor alpha Leu162Val 유전자 다형성과 대사증후군간의 관련성 (Association between Genetic Polymorphism of Peroxisome Proliferator-Activated Receptor Alpha Leu162Val and Metabolioc Syndrome in Korean)

  • 신승철;송혜순;홍영습;곽종영;유병철;이용환
    • 생명과학회지
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    • 제16권2호
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    • pp.199-205
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    • 2006
  • Peroxisome proliferator-activated receptors alpha (PPAR $\alpha$)는 지질대사와 관련하여 대사증후군 발생과 관련이 있을 수 있는 강력한 잠재 유전자로 고려되고 있으므로 한국인에 있어서 PPAR$\alpha$ L162V 유전자 다형성과 대사증후군과의 연관성을 확인하고자 고신대학교 복음병원에서 2004년 12윌에서 2005년 7월 사이에 건강진단을 받았던 수진자 542명(대사 증후군 : 262명, 정상인 : 280명)을 대상으로 신장, 체증, 체질량지수, 허리둘레와 수축기와 이완기 혈압, 공복 혈당, 총콜레스테롤, HDL 콜레스테롤, LDL 콜레스테롤과 중성지방 수치를 측정하였으며, 대사증후군의 정의는 혈압, 공복 혈당, HDL 콜레스테롤, 중성지방은 NCEP ATP III의 기준을 적용하였고, 허리둘레는 WHO 아시아-서태평양 기준을 적용하였다. PCR-ASO (polymerase chain reaction allele-specific oligonucleotide) 방법에 의해 대상자들의 PPAR$\alpha$ L162V 유전자 다형성을 확인하였다. 연구결과 PPAR$\alpha$ 484번 염기서열의 $C{\rightarrow}G$ 돌연변이가 나타난 사람은 조사대상자 542명 가운데 1명(0.2%) 이었다. 한국인에서는 PPAR$\alpha$ L162V 유전자 다형성이 거의 일어나지 않았으며, 이의 확인을 위하여 더욱 많은 사람을 대상으로 연구가 진행되어야 할 필요가 있을 것으로 생각된다.