• Applied Biological Chemistry
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• 제16권3호
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• pp.112-117
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• 1973

The very low density apolipoproteins were separated by a newly developed method of isoelectric focusing in a narrow pH gradient. Four polypeptides were isolated that differed from the major proteins of the high density or low density lipoproteins. Three of these proteins had indistinguishable amino acid compositions, but different isoelectric points, COOH-terminal alanine, no isoleucine, cysteine or cystine. Two of these polypeptides had $NH_2-terminal$ serine. The polymorphism of apolipoprotein-Ala, so designated from the COOH-terminal residue, was related to sialic acid content; one form contained 2 moles of sialic acid per mole of protein, the second, 1 mole of protein, and the third, no sialic acid. The fourth polypeptide had an amino acid composition different from the first three polypeptides and from other polypetides obtained from very low density lipoprotein. This polypeptide had $NH_2-terminal$ threonine, COOH-terminal resistant to carboxypeptidase A, no histidine, cysteine, cystine or sialic acid. These four polypeptides constituted approx. 40% of the total protein in very low density lipoprotein.

• Childhood Kidney Diseases
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• 제26권1호
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• pp.25-30
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• 2022

Dyslipidemia in nephrotic syndrome (NS) is often characterized by marked increases in the levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol, and other lipoproteins, such as very low-density lipoprotein, intermediate-density lipoprotein, and lipoprotein(a). It has been suggested that impaired catabolism of lipoproteins and cholesterol is mainly due to decreased lipoprotein lipase and hepatic lipase activity, and increased biosynthesis of lipoproteins in the liver. The management strategies for dyslipidemia in patients with NS consist of lifestyle modification, lipid-lowering agents represented by statins, second-line agents such as fibrates and bile acid sequestrants, and lipid apheresis. Compared with dyslipidemia in adult NS patients, whose risks of atherosclerotic disease and progressive renal injury are considered high, clinical data on dyslipidemia in pediatric NS patients are limited. Therefore, it is necessary to pay more attention to the evaluation and management of dyslipidemia in pediatric patients with NS in clinical practice.

• Journal of Nutrition and Health
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• 제19권5호
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• pp.296-303
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• 1986

흰쥐의 lipoprotein을 제거한 혈장내의 지질전이 활성도와 지진전이를 저해하는 활성도를 측정하였다. 지질전이 활성도의 측정은 방사성 동위원소가 함유된 cholesteryl ester (CE)와 triglyceride (TG) 로 표지된 인체의 혈장 low density lipoprotein 으로부터 high high density lipoprotein(HDL) 으로 전이되는 방사성 동위원소의 양을 측정하여 계산하였다. 지질전이 저해 활성도는 정제한 인체 혈장 지질전이 단백질에 의한 지질전이를 저해하는 정도로서 측정하였다. 흰쥐의 혈장에는 지질전이 활성도가 거의 없으나, 지질전이를 저해하는 활성도는 존재하였다. 지질전이 저해정도는 측정용액내의 lipoprotein 양이 증가할수록 감소하였다. 일반적으로 흰쥐의 HDL은 인체의 HDL에 비하여 CE 의 함량은 높으며 TG의 함량은 낮다. 흰쥐의 혈장에 인체의 혈장으로부터 정제한 지질전이 단백질을 가하여 37$^{\circ}C$에 24시간 두었을 때, HDL 로부터 very low density lipoprotein (VLDL)으로 CE가 이동하여 VLDL 의 CE 함량이 4배나 증가하였다. 반면에 VLDL로부터 HDL$_2$로TG가 이동하여 $HDL_2$의 함량은 TG함량은 9배나 증가하였다. 이와같은 현상은 흰쥐의 혈장 Lipoportein이 지질전이의 기질로서의 결함은 없음을 보여준다. 따라서 지질대사에 관한 실험에서의 흰쥐에 의한 실험결과의 해석에는 인체 혈장에 비하여 혈장에는 lipoprotein사이의 중성지질의 전이나 교환이 거의 없다는 특성이 고려되어야한다.

• Preventive Nutrition and Food Science
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• 제7권2호
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• pp.133-138
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• 2002

To examine the cholesterol-towering effects of extruded products made with cassava starch (CS) and blends of cassava starch with either resistant starch (CS-RS) or oat fiber (CS-OF) hamsters were fed with diets containing a high-cholesterol (2%) and high-fat (17%) diet for 20 days. Hamsters fed with a diet containing no cholesterol were used as a control. Total cholesterol (TC) levels in the CS-RS and CS-OF groups were significantly (p>0.05) lower compared to the CS group by 11.5% and 8.5%, respectively. Also, the diets containing fibers decreased the value of low-density lipoproteins plus very low-density lipoproteins fraction by 32.4% (CS-RS diet) and 51.7% (CS-OF), respectively, as compared to the CS diet. Total lipid values were significantly (p<0.05) lower in hamsters fed the CS-RS diet (916 mg/dL) and CS-OF diet (964 mg/dL) as compared to those fed the CS diet (1661 mg/dL). The results obtained in this study suggest that extruded products containing cassava starch blended with either resistant starch or oat fleer, could prevent health problems associated with high levels of cholesterol and hypertriglyceridemia induced by a high cholesterol and fat diet.

• 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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• 제29권12호
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• pp.1748-1755
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• 2016

An experiment was conducted to investigate the effect of niacin supplementation on hepatic lipid metabolism in rabbits. Rex Rabbits (90 d, n = 32) were allocated to two equal treatment groups: Fed basal diet (control) or fed basal diet with additional 200 mg/kg niacin supplementation (niacin). The results show that niacin significantly increased the levels of plasma adiponectin, hepatic apoprotein B and hepatic leptin receptors mRNA (p<0.05), but significantly decreased the hepatic fatty acid synthase activity and adiponectin receptor 2, insulin receptor and acetyl-CoA carboxylase mRNA levels (p<0.05). Plasma insulin had a decreasing tendency in the niacin treatment group compared with control (p = 0.067). Plasma very low density lipoproteins, leptin levels and the hepatic adiponectin receptor 1 and carnitine palmitoyl transferase 1 genes expression were not significantly altered with niacin addition to the diet (p>0.05). However, niacin treatment significantly inhibited the hepatocytes lipid accumulation compared with the control group (p<0.05). In conclusion, niacin treatment can decrease hepatic fatty acids synthesis, but does not alter fatty acids oxidation and triacylglycerol export. And this whole process attenuates lipid accumulation in liver. Besides, the hormones of insulin, leptin and adiponectin are associated with the regulation of niacin in hepatic lipid metabolism in rabbits.

• Molecules and Cells
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• 제44권2호
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• pp.116-125
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• 2021

Cardiovascular diseases (CVDs) are the most common cause of death in patients with nonalcoholic fatty liver disease (NAFLD) and dyslipidemia is considered at least partially responsible for the increased CVD risk in NAFLD patients. The aim of the present study is to understand how hepatic de novo lipogenesis influences hepatic cholesterol content as well as its effects on the plasma lipid levels. Hepatic lipogenesis was induced in mice by feeding a fat-free/high-sucrose (FF/HS) diet and the metabolic pathways associated with cholesterol were then analyzed. Both liver triglyceride and cholesterol contents were significantly increased in mice fed an FF/HS diet. Activation of fatty acid synthesis driven by the activation of sterol regulatory element binding protein (SREBP)-1c resulted in the increased liver triglycerides. The augmented cholesterol content in the liver could not be explained by an increased cholesterol synthesis, which was decreased by the FF/HS diet. HMG-CoA reductase protein level was decreased in mice fed an FF/HS diet. We found that the liver retained more cholesterol through a reduced excretion of bile acids, a reduced fecal cholesterol excretion, and an increased cholesterol uptake from plasma lipoproteins. Very low-density lipoproteintriglyceride and -cholesterol secretion were increased in mice fed an FF/HS diet, which led to hypertriglyceridemia and hypercholesterolemia in Ldlr-/- mice, a model that exhibits a more human like lipoprotein profile. These findings suggest that dietary cholesterol intake and cholesterol synthesis rates cannot only explain the hypercholesterolemia associated with NAFLD, and that the control of fatty acid synthesis should be considered for the management of dyslipidemia.

• Journal of Nutrition and Health
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• 제12권3호
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• pp.9-23
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• 1979

The known risk factors for atherosclerosis include plasma low density lipoproteins (LDL)or Cholesterol, low PUFA in the diet, hypertension, and high Na intake, obesity, diabetes, lack of exercise, cigarette smoking, sugar, low fiber and nicotinic acid in the diet, sources of Protein foods, and Psychological factors. Among various dietary factors, fat is known as the most serious causative agent for atherosclerosis. The genetic factor is a18o known as an important one but is out of scope in this paper. Since atherosclerosis is a progressive disease which may develop for many years before showing any definitive symptoms, it is very important to develop preventive programs especially in the country like Korea that is not quite overdevelopted as some western countries. In this paper all the factors mentioned above were reviewed and the dietary suggestion were made on the basis of the content of polyunsaturated and saturated fat in the diet to prevent or/and to cure this disease. Most of the available data on diet therapy with emphasis. on P/S ratio were tabulated together. after tile patient's habitual dietary intake is analized the guidelines of personalized fat-controlled diet can be recommended. It is of utmost importance to develop Korean diets for beth prevention and cure of atherosclerosis emphasizing individual eating habit in the near future which can be more Practicaly used both at home and in the hospital.

• BMB Reports
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• 제35권2호
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• pp.172-177
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• 2002

We previously reported that cholesteryl ester transfer protein (CETP) inhibitory peptides (designated $P_{28}$ and $P_{10})$ have anti-atherogenic effects in hypercholesterolemic rabbits (Biochim. Biophys. Acta (1998) 1391, 133-144). To further investigate those effects, we studied rabbit plasma that was collected after 30 h of a $P_{28}$ or $P_{10}$ injection. We found that there is a strong correlation between the in vivo CETP inhibition effects and alterations of lipoprotein particle size distribution in rabbit plasma, as determined on an agarose gel electrophoresis and gel filtration column chromatography. In vivo effects of the peptide were observed again in C57BL/6 mice that expressed simian CETP. The $P_{28}$ or $P_{10}$ peptide ($7\;{\mu}g/g$ of body weight) that was dissolved in saline was injected subcutaneously into the mice. The $P_{28}$ injection caused the partial inhibition of plasma CETP activity up to 50%, decreasing the total plasma cholesterol concentration by 30%, and increasing the ratio of HD/total-cholesterol concentration by 150% in the CETP-transgenic (tg) mice. The CETP inhibition by the $P_{28}$ or $P_{10}$ made alterations that modulated the size re-distribution of the lipoproteins in the blood stream. Particle size of the very low (VLDL) and low density lipoproteins (LDL) from the peptide-injected group was highly decreased compared to the saline-injected group (determined on the gel filtration column chromatography). In contrast, The HDL particle size of the $P_{28}$-injected group increased compared to the control group (saline-injected). The expression level of the CETP mRNA of the $P_{28}$-injected CETP-tg mouse appeared lower than the saline-injected CETP-tg mouse. These results suggest that the injection of the CETP inhibitory peptide could affect the CETP expression level in the liver by influencing lipoprotein metabolism.

• The Korean Journal of Physiology
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• 제16권2호
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• pp.195-207
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• 1982

장기적(長期的)인 채식섭취(菜食攝取)가 혈청(血淸)의 lipoprotein, cholesterol 및 단백량(蛋白量)에 미치는 영향(影響)을 알아보기 위하여 결은 여승(女僧) 45명(名)($20{\sim}35$세)과 대조군(對照群)으로 여대생(女大生) 29명(名)($20{\sim}22$세)을 연구대상(硏究對象)으로 하였다. 하루 열량섭취(熱量攝取)는 여승(女憎)들이 1,945 kcal 였고 여대생(女大生)은 1,815 kcal 였다. 열량구성비율(熱量構成比率)은 여승(女僧)들이 탄수화물(炭水化物) : 단백질(蛋白質) : 지방(地方)=84 : 11 : 5였고 학생(學生)은 70 : 15 : 15였으며 이는 여승(女僧)들의 탄수화물(炭水化物) 편중(偏重) 및 지방섭취부족(脂肪攝取不足)을 보여준다. 신체계측결과(身體計測結果) 여승(女僧)들은 여대생(女大生)보다 신장(身長)을 제외(除朴)하고, 체중(體重), 지방층(脂肪層)두께, 체표면적(體表面積) 및 비만도계수(肥滿度係數)가 모두 높았다. 수축기(收縮期) 및 이완기혈압(弛緩期血壓)은 여승(女憎)과 여대생(女大生)이 거의 같았다. 혈청(血淸)의 총지방(總脂肪), cholesterol 및 단백량(蛋白量)은 여승(女憎)과 여대생간(女大生間)에 유의(有意)한 차이(差異)가 없었다. 그러나 전기영동(電氣泳動)으로 분획(分劃)하여 혈청(血淸)의 high density lipoprotein(HDL), very low density lipoprotein(VLDL) 및 low density lipoprotein(LDL)량(量)을 비교(比較)해 본 결과(結果), 여승(女憎)들의 HDL은 여대생(女大生)보다 낮았으나 LDL은 유의(有意)하게 높았다. Cholesterol분획결과(分劃結果)도 역시 여승(女憎)들의 HDL-cholesterol값은 여대생(女大生)보다 유의(有意) 하게 낮은 반면(反面) LDL-cholesterol은 유의(有意)하게 높았다. Lipoprotein과 cholesterol간(間)의 상관계수(相關係數)(r)를 계산(計算)한 결과(結果) LDL과 LDL-cholesterol(r=0.40), VLDL과 VLDL-cholesterol(r=0.85), HDL과 HDL-cholesterol(r=0.45), 혈청총지방량(血淸總脂防量)과 cholesterol(r=0.66) 및 혈청(血淸) 총(總) cholesterol과 LDL-cholesterol(r=0.79) 간(間)에는 유의(有意)한 상관관계(相關關係)를 보여주었다. 그러나 혈청(血淸) cholesterol과 음식섭취(飮食攝取) 및 신체계측결과간(身體計測結果間)에는 유의(有意)한 상관관계(相關關係)가 나타나지 않았다. 혈청단백량(血淸蛋白量)은 여승(女憎)과 여대생간(女大生間)에 차이(差異)가 없었다. 이상(以上)의 결과(結果)는 여승(女憎)들의 장기적(長期的)인 채식섭취(菜食攝取)로 인(因)해 인체(人體)의 lipoprotein 및 cholesterol 대사(代謝)에 영향(影響)이 있음을 시사(示唆)해 주고 있다.