• 생약학회지
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• 제15권4호
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• pp.206-212
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• 1984

The effect of saponin fractions of Panax ginseng root on the interactions of human plasma lipoproteins and lecithin dispersions with dextran sulfate were studied in order to examine the effect of Panax ginseng on the lipid accumulation in the aorta. The total saponin fraction and protopanaxadiol glycosides of Panax ginseng root seemed to slightly enhance the interaction of low density lipoproteins with dextran sulfate in the absence of divalent metal ions. Protopanaxatriol glycosides remarkably inhibited the interaction of low density lipoproteins with dextran sulfate. However, all of these three saponin fractions of Panax ginseng root showed the tendency of inhibition to the interaction of high density lipoproteins with dextran sulfate in the presence of divalent metal ions by the order of protopanxatriol glycosides, protopanaxadiol glycosides and total saponin. Three saponin fractions of Panax ginseng exerted almost same tendency to the interaction of lecithin dispersions with dextran sulfate in the presence of divalent metal ions as the interaction of low density lipoproteins with dextran sulfate absence of divalent metal ions.

• 한국식품영양과학회지
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• 제23권3호
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• pp.530-539
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• 1994

최근 지방 섭추의 증가에 따른 혈관계 질병이 증가 추세에 있다. 이러한 동맥경화 및 고지질의 질병은 지질 단백질(lipoprotein)과 관련하여, LDL 및 산화 LDL의 특성을 중심으로 고찰하였다. 인체의 혈장에 함유된 LDL 함량의 증가는, 동맥경화와 직결되는 것을 의미하며, 이러한 LDL은 매우 hydrophobic한 특성을 가진 550Kd의 단일 polypeptide인 Apo B-100라는 단백질이, 지질성분인 triglyceide, phospholipid 및 cholesterol와 결합되어 있다. 최근 이러한 LDL은 산화(oxidation)되는 경우, 정상적인 LDL-receptor pathway를 따르지 않고, macrophang와 결합하므로서, foarn cell을 형성하여 동백경화가 촉진되는 것으로 알려지고 있다.

• 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.

• 생명과학회지
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• 제8권4호
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• pp.353-359
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• 1998

This study was initiated to antioxidant activity of silybin on oxidation of human low density lipoproteins(LDL). Siltbin was extracted from Silybum marianum by the combination of fractionation and it was futher purified by silica gel column chromatography, and isolated active substances were identified silybin by IR, NMR and GC-MS. siltbin inhibited the ozidation of human low density lipoprotein(LDL) mediated by 5$^{\mu}$m CU $^{2+}$ ion in a dose dependent manner. LDL oxidation by congugated dines formation was completely inhibited by silybin at a concentration of 5$^{\mu}$M. The results provide a possibility that silybin might protect LDL against oxidation in atherosclerotic lessions.

• Preventive Nutrition and Food Science
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• 제4권2호
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• pp.145-151
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• 1999

Apolipoprotein B-100 (apo B-100) is an important component in plasma low density lipoproteins (LDL). It function as the ligand for the LDL receptor in peripheral cells. The LDLs are removed from the circulation by both high-affinity receptor-mediated and receptor-independant pathways. LDLs are heterogeneous in their lipid content, size and density and certain LDL subspecies increase risk of atherosclerosis due to differences in the conformation of apo B in the particle. In the present study , surface and core peptide fraction of Apo B-100 have been characterized by comparing peptide-mapping and fluorescence spectroscopy. Surface fragments of apo B-100 were generated by digestion of LDL with either trypsin , pronase, or pancreatin elastase. Surface fractions were fractionated on a Sephadex G-50 column. The remaining core fragments were delipidated and redigested with the above enzymes, and the resulting core peptides were compared with surface peptides. Results from peptide-mapping by HPLC showed pronase-digestion was more extensive than trypsin -digestion to remove surface peptide fraction from LDL. Fluorescence spectra showed that core fractions contained higher amount of tryptophan than surface fractions, and it indicated that core fraction wa smore hydrophobic than surface fractions. A comparison of the behavior of the core and surface provided informations about the regions of apo B-100 involved in LDL metabolism and also about the structural features concerning the formation of atherosclerosis.

• BMB Reports
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• 제43권8호
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• pp.535-540
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• 2010

Patients with hemorrhagic fever with renal syndrome (HFRS) often exhibit altered serum lipid and lipoprotein profile during the oliguric phase of the disease. Serum lipid and lipoprotein profiles were assessed during the oliguric and recovery phases in six male patients with HFRS. In the oliguric phase of HFRS, the apolipoprotein (apo) C-III content in high-density lipoproteins (HDL) was elevated, whereas the apoA-I content was lowered. The level of expression and activity of antioxidant enzymes were severely reduced during the oliguric phase, while the cholesteryl ester transfer protein activity and protein level were unchanged between the phases. In the oliguric phase, electromobility of $HDL_2$ and $HDL_3$ was faster than in the recovery phase. Low-density lipoprotein (LDL) particle size was smaller and the distribution was less homogeneous. Patients with HFRS in the oliguric phase had severely modified lipoproteins in composition and metabolism.

• 한국환경성돌연변이발암원학회지
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• 제11권2호
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• pp.99-106
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• 1991

수용체를 통한 저밀도 지방단백질(LDL)의 세포내 이동과 함께 일어나는 지용성 돌연변이원인 벤조피렌의 세포내 이동에 관하여 조사하였다. [$^3$H]로 표지된 벤조피 렌의 Hep 2 세포내 이동을 조사한 결과, 배지에 LDL을 첨가한 경우. LDL이 첨가되지 않은 경우보다 3배나 많은 양의 벤조피렌이 세포내로 이동하여 세포내 물질과 결합하였음을 관찰하였다. 그러나 10$\mu$M의 황산구리로 LDL의 아포단백질을 변형 시킨 후 변형된 LDL을 배지에 첨가하고 벤조피렌의 세포내 이동을 조사한 건과, 정상 LDL이 첨가된 경우보다 벤조피렌의 세포내 이동이 현저히 감소하였다. 이 결과는 LDL을 이동체로 이용한 벤조피렌의 세포내 이동이 세포의 수용체와 LDL의 아포 단백질의 인식과정을 거친다는 사실을 뒷받침한다고 여겨진다.

• Preventive Nutrition and Food Science
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• 제1권1호
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• pp.134-142
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• 1996

Diabetes carries an increased risk of atherosclerotic disease that is not fully explained by known car-diovascular risk factors. There is accumulating evidence that advanced glycation of structural proteins, and oxidation and glycation of circulating lipoproteins, are implicated in the pathogenesis of diabetic ather-osclerosis. Reactions involving glycation and oxidation of proteins and lipids are believed to contribute to atherogenesis. Glycation, the nonenzymatic binding of glucose to protein molecules, can increase the ather-ogenic potential of certain plasma constituents, including low density lipoptotein(LDL). Glycation of LDL is significant increased in diabetic patients compared with normal subjects, even in the presence of good glycemic control. Metabolic abnormalities associated with glycation of LDL include diminished recognition of LDL by the classic LDL receptor; increased covalent binding of LDL in vessel walls ; enhanced uptake of LDL by the macrophages, thus stimulating foam cell formation ; increased platelet aggregation; formation of LDL-immune complexes ; and generation of oxygen free radicals, resulting on oxidative damage to both the lipid and protein components of LDL and to any nearby macromolecules. Oxidized lipoproteins are characterzied by cytotoxicity, potent stimulation of foam cell formation by macrophages, and procoagulant effects. Combined glycation and oxidation, "glycoxidation" occurs when oxidative reactions affect the initial products of glycation, and results in irreversible structural alterations of proteins. Glycoxidation is of greatest significance in long lived proteins such as collagen. In these proteins, glycoxidation products, believed to be atherogenic, accumulate with advancing age : in diabetes, their rate of accumulate is accelerated. Inhibition of glycation, oxidation and glycoxidation may form the basis of future antiaterogenic strategies in both diabetic and nondiabetic individuals.dividuals.

• Molecules and Cells
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• 제25권3호
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• pp.347-351
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• 2008

Several lines of evidence indicate that the oxidative modification of protein and the subsequent accumulation of the modified proteins have been found in cells during aging, oxidative stress, and in various pathological states including premature diseases, muscular dystrophy, rheumatoid arthritis, and atherosclerosis. The important agents that give rise to the modification of a protein may be represented by reactive aldehydic intermediates, such as ketoaldehydes, 2-alkenals and 4-hydroxy-2-alkenals. These reactive aldehydes are considered important mediators of cell damage due to their ability to covalently modify biomolecules, which can disrupt important cellular functions and can cause mutations. Furthermore, the adduction of aldehydes to apolipoprotein B in low-density lipoproteins (LDL) has been strongly implicated in the mechanism by which LDL is converted to an atherogenic form that is taken up by macrophages, leading to the formation of foam cells. During the search for an endogenous inducer of cyclooxygenase-2 (COX-2), an inducible isoform responsible for high levels of prostaglandin production during inflammation and immune responses, 4-hydroxy-2-noennal (HNE), one of the most representative lipid peroxidation product, has been identified as the potential inducer of COX-2. In addition, the following study on the molecular mechanism of the COX-2 induction by HNE has unequivocally established that a serum component, which is eventually identified to be denatured LDL, is essential for COX-2 induction. Here I review current understanding of the mechanisms by which HNE in cooperation with the serum component activates gene expression of COX-2.

• 한국식품영양과학회지
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• 제24권3호
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• pp.362-370
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• 1995

Human plasma low density lipoprotein(LDL) is the main carrier for cholesterol, and recent studies suggest the normal LDL can be readily oxidized by free radical and not interact with LDL receptor. Lipoprotein pariticles are consisted of lipid andprotein, and fatty acids of lipoproteins are prone to oxidation. LDL particles readily undergo oxidative modification by copper. From the results, oxidized LDL altered its biological properties. A marked increase in the electrophoretic mobility of LDl on agarose gel indicated that negative surface charge of the LDL particles was increased. Also, the results from the HPLC showed that oxidized LDL was degraded into several polypeptides nonenzymatically. Degradation tests which measured the amount of 5-IAF labelled oxidized LDL were carried out by monocyte and hepatocyte cell culture. Hepatocyte cell culture of modified LDL did not show consistent pattern. However, binding rate of modified LDL with HMDM(human monocyte derived macrophage) was enhanced with oxidation, but was retarded by addition of antioxidants(hyaluronic acid, vitamin A, vitamin E). Also comparisons of oxidized-LDL, acetyl-LDL and MDA-LDL showed significant differences in the chemical properteis and binding affinity to HMDM. Thus, modificaition of normal LDL altered its biological properties.