• BMB Reports
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• 제33권2호
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• pp.148-154
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• 2000

The glycation process plays an important role in accelerated atherosclerosis in diabetes, and the uptake of atherogenic lipoproteins by macrophage in the intima of the vessel wall leads to foam cell formation, an early sign of atherosclerosis. Besides the lipolytic action on the plasma triglyceride component, lipoprotein lipase (LPL) has been reported to enhance the cholesterol uptake by arterial wall cells. In this study, some properties of LPL-mediated low-density lipoprotein (LDL) uptake and the effect of LDL glycation were investigated in RAW 264.7 cell, a murine macrophage cell line. In the presence of LPL, $^{125}I$-LDL binding to RAW 264.7 cells was increased in a dose-dependent manner. At concentrations greater than $20\;{\mu}g/ml$ of LPL, LPL-mediated LDL binding was increased about 17-fold, achieving saturation. Without LPL, both very low-density lipoprotein (VLDL) and high-density lipoprotein (HDL) were ineffective in blocking the binding of $^{125}I$-LDL to Cells. However, LPL-enhanced LDL binding was inhibited about 50% by the presence of VLDL, while no significant effect was observed with HDL. Heat inactivation of LPL caused a 30% decrease of LDL binding. In the presence of LPL, the cells took up 40% of cell-bound native LDL. No significant difference was observed in cell binding between native and glycated LDL. However, the uptake of glycated LDL was significantly greater than that of native LDL, reaching to 70% of the total cell bound glycated LDL. These results indicate that LPL can cause the significant enhancement of LDL uptake by RAW 264.7 cells and the enhanced uptake of glycated LDL in the presence of LPL might play an important role in the accelerated atherogenesis in diabetic patients.

• Asian-Australasian Journal of Animal Sciences
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• 제14권11호
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• pp.1592-1597
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• 2001

Sixteen pigs from 2 distinct genetic lines (LGAH and VFIL) obtained after eight generations of divergent selection for high (H) and low (L) lean tissue growth rate with ad-libitum feeding (LGA) and voluntary feed intake (VF1), respectively, were used in this study. The objectives of this investigation were to establish appropriate working conditions for the postheparin plasma lipoprotein lipase (LPL) assay and to study relationships between fat deposition and plasma lipids, very low density lipoprotein (VLDL) lipids, VLDL-subfractions and postheparin plasma LPL activity in growing pigs. Four preliminary experiments were performed to determine the appropriate working conditions for the postheparin plasma LPL assays. Postheparin plasma preincubated with SDS (20-50 mM) at $26^{\circ}C$ for 45 minutes inhibited hepatic lipase activity. A total of $2{\mu}l$ VLDL/assay produced maximum stimulation of LPL activity. Postheparin plasma protein and increasing incubation time contributed an optimum response. LGAH pigs had a significantly higher proportion subtraction 2 than VFIL pigs. No differences were observed in postheparin plasma LPL activity and backfat thickness for two lines of pigs. There were positive correlations between backfat thickness and proportion of subtractions 2 and postheparin plasma LPL activity but the results were not statistically significant. Backfat thickness was not statistically correlated with proportion of subtraction 2 and postheparin plasma LPL activity in a multiple regression analysis. It is believed that the apolipoprotein E, which is present in higher quantities in VLDL-subfraction 2 plays an important role for clearing VLDL triacylglycerol into adipose tissue. LPL activity of pigs can be measured by using postheparin plasma technique. If the relationships of backfat thickness and VLDL-subfraction 2 and postheparin plasma LPL activity can be established, it suggests that these parameters could be used as indicators in selection programmes. Further experiments need to be conducted by using larger sample size and different breed of pigs with greater differences in backfat thicknesses to confirm these trends.

• 생명과학회지
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• 제17권10호
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• pp.1330-1335
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• 2007

마늘을 발효시켜 만든 흑마늘의 지질 산화 억제 및 사람 Low Density Lipoprotein (LDL)에 대하여 항산화 활성을 실험하였다. 표준품으로서 마늘의 주성분인 alliin과 흑마늘의 에탄올과 물 추출물의 전자공여능을 각각 비교하여 측정한 결과 흑마늘 에탄을 추출물이 효능이 가장 높았다. 사람 LDL을 $Cu^{2+}$유도 LDL로 산화시킬 때 그 항산화능은 각 시료를 $10\;{\mu}g/ml$ 및 $20\;{\mu}g/ml$ 씩 첨가하며 TSARS를 측정한 결과 에탄을 추출물이 항산화 활성이 가장 높았으며 용량 의존형으로 나타났다. 흑마늘의 에탄올과 물추출물을 $10\;{\mu}g/ml$ 및 $20\;{\mu}g/ml$ 첨가한 후 J774 유도 산화에 대한 항산화 효과를 측정한 결과 각 추출물은 항산화 효과가 있었고 용량 의존형의 항산화 활성을 나타내었다. 흑마늘의 각 추출물을 이용한 실험에서 전기영동 이동상은 대조구에 비하여 $10\;{\mu}g/ml$ 및 $20\;{\mu}g/ml$에서 산화를 억제하였고 공액 2중 결합에 의한 실험에서도 항산화 효과가 있었으며 $20\;{\mu}g/ml$의 농도에서 거의 억제되었다.

• 한국식품영양과학회지
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• 제23권6호
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• pp.887-893
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• 1994

This study was undertaken to dtermine whether dietary fibers had an effect on postprandial plasma lipoprotein and liver lipid composition in rats. Each experimental diet ocntained 10 % dietary fiber by weight. All animals were sacrificed in postprandial state. Sodium alginate-fed animals has significantly lower plasma cholesterol, VLDL-, LDL-cholesterol, TG, and protein levels than did the fiber-free control group. In addition, liver cholesterol and TG concentrations were the lowest in sodium alginate -fed animals. There was no significant change in HDL-cholesterol levels among experimental groups. Cellulose-fed animals also have lower plasma cholesterol and TG levels than fiber-free controls, but liver TG concentrations were not different from those in fiber-free controls. This study demonstrates that dietary fiber included in the diet of rats is able to alter postprandial lipoportein cholesterol and TG, and that sodium alginate, a soluble fiber, was the most effective in lowering plasma and liver cholesterol and TG.

• 한국식품위생안전성학회지
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• 제12권1호
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• pp.1-8
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• 1997

This study was performed to evaluate the antioxidant activity of silymarin against human low density lipoproteins(LDL) oxidation. Silymarin extracted from Silybum marianum was successively purified with solvent fractionation and followed by silica gel column chromatography. The active substances were separated by HPLC and the isolated active substances, silymarin were identified by IR, NMR, GC-MS as silymarin. Silymarin inhibited at the 5 $\mu$M Cu2+-mediated oxidation of human low density lipoprotein (LDL) in a dose dependent manner. Silymarin completely inhibited LDL oxidation at 50 $\mu\textrm{g}$/$m\ell$ concentration. These findings suggest that silymarin may protect LDL against oxidation in atherosclerotic lessions.

• Clinical and Experimental Reproductive Medicine
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• 제29권4호
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• pp.279-285
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• 2002

Objective : To evaluate the difference between estrogen only therapy and estrogen-androgen combination therapy in surgical menopause patients. Materials and Method: Surgical menopause patients received 0.625 mg conjugated equine estrogens or 0.625 mg conjugated equine estrogens plus 1.25 mg methyltestosterone for 2 years. Bone mineral density, menopausal symptoms, lipoprotein profiles were measured. Results: Both groups showed increased bone mineral density. In the combination group, total cholestero l, high density lipoprotein cholesterol and triglycerides decreased. In the estrogen only group, low density lipoprotein cholesterol decreased but high density lipoprotein cholesterol increased significantly. In both groups, menopausal symptoms were much improved. Side effects were easily tolerated in both groups. Conclusions: Estrogen-androgen combination therapy had comparable benefits compared with estrogen only therapy.

• Journal of Chest Surgery
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• 제26권1호
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• pp.12-17
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• 1993

Among the many deleterious effects of cardiopulmonary bypass[CPB], deterioration of plasma lipoprotein is a significant problem. Break-down of lipoprotein releases free fatty acids into the systemic circulation which, in turn, can cause microembolism. This study conducted on 30 patients undergoing CPB, was designed to elucidate the changes of plasma lipoproteins during and after CPB. Blood samples were taken at pre-CPB, on-CPB 30 minutes and 60 minutes, postoperative 1st, 3rd, 7th days. The levels of total cholesterol and triglyceride were measured and lipoprotein was subdivided into three kinds on electrophoresis. During CPB, the amounts of plasma total cholesterol and triglyceride decreased significantly and were recovered to pre-CPB levels after postoperative third day. There was no significant correlation between the duration and the severity of decrease in plasma total cholesterol and triglyceride levels. During CPB, the fraction of VLDL decreased and that of LDL increased. After cessation of CPB, the fraction of LDL decreased and that of HDL increased. After postoperative 1st day, the fraction of HDL decreased and that of LDL increased.

• 생명과학회지
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• 제9권1호
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• pp.99-105
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• 1999

Bacillus sp. RH-5로 배양한 배양액을 silica gel column (8.0cmX100cm)chromatography를 행하여 chloroform : methanol = 90 : 10인 항산화 분획층을 얻어 TLC 법에 의해 활성이 있는 물질을 분리하여 thiocyanate method로 활성을 측정하여 본 결과 Vit. E($10^{-2}$ mol)보다 좋았으며 BHA, BHT와는 비슷한 결과를 나타내었다. 한편 $5_\muM$ $CuSO_4$ 촉매 사람 Low Density Lipoprotein(LDL)의 산화에 항산화 활성이 알려진 Fraction 3의 band 4를 각각 100 및 200$\mu$g/$m\ell$ 농도로 $37^{\circ}C$에서 18시간 배양한 결과 LDL의 산화에 대한 억제효과가 좋았다. Fraction 3의 band 4를 HPLC로 정제한 후 IR. NMR 및 GC/MASS.로 확인한 결과 5-hydroxyndole로 확인되었다.

• Journal of Periodontal and Implant Science
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• 제50권3호
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• pp.135-145
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• 2020

Purpose: The aim of this study was to evaluate the serum levels of oxidized low-density lipoprotein (oxLDL), anti-oxLDL, and myeloperoxidase (MPO) in hyperlipidemic patients with periodontal disease. Methods: This study included 123 patients with hyperlipidemia categorized based on metabolic control as mild to moderate (H1) (n=66) or poor (H2) (n=57), as well as systemically healthy controls (C) (n=68). Serum levels of lipids, oxLDL, anti-oxLDL, and MPO were evaluated, along with clinical periodontal parameters. Results: The percentage of bleeding on probing (BOP%) and the clinical attachment level were significantly higher in the H2 group than in the C group. Patients with hyperlipidemia had a relatively high risk of developing periodontal disease. The oxLDL and anti-oxLDL levels were higher in H2 patients with periodontitis than in the control or H1 patients with periodontitis. In the H1 and H2 groups, the ratio of total cholesterol to high-density lipoprotein was significantly correlated with gingival index, BOP%, and oxLDL levels. Conclusions: Our findings indicate that the lipoprotein-associated inflammatory mediators of oxLDL, anti-oxLDL, and MPO may play an important role in the relationship between periodontal disease and hyperlipidemia.

• 한국컴퓨터정보학회논문지
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• 제21권12호
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• pp.139-145
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• 2016

In this paper, we propose to evaluate the effect of Resistin-like molecule alpha (Retnla) on the expression of transporters involved in modulating concentrations of peripheral cholesterol and plasma high-density lipoprotein (HDL) cholesterol. High levels of blood cholesterol are a well-recognized risk factor for atherosclerosis and are eliminated via the process of reverse cholesterol transport (RCT). We recently showed that Retnla ameliorates hypercholesterolemia and atherosclerosis by increasing biliary cholesterol secretion, the final step of the process, in low-density lipoprotein receptor-deficient mice. However, the role of Retnla in HDL-mediated cholesterol efflux, initial step of RCT pathway, is not yet clear. To identify cholesterol transport genes regulated by Retnla, we performed an extensive microarray-based gene expression screen using livers from Retnla-overexpressing (Tg) mice and control animals. The most significant change in Retnla-Tg mice was an upregulation of ATP-binding cassette sub-family G member 4 (Abcg4) transport and was validated using quantitative RT-PCR. The validated gene was also induced by treatment of purified Retnla protein in RAW 264.7 cells incubated with acetylated low-density lipoprotein and Hepa1c1c7 cells. Taken together, these results indicates that Retnla might also accelerate initial step of RCT pathway, suggesting therapeutic value of Retnla in the treatment of hypercholesterolemia and atherosclerosis.