• Asian-Australasian Journal of Animal Sciences
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• v.9 no.1
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• pp.1-25
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• 1996

The pathogenesis of atherosclerosis can not be summarized as a single process. Lipid infiltration hypothesis and endothelial injury hypothesis have been proposed and investigated. Recent developments show that there are many points of potential interactions between them and that they can actually be regarded as two phases of a single, unifying hypothesis. Among the many risk factors of atherosclerosis, plasma homocysteine and lipoprotein(a) draw a considerable interest because they are independent indicators of atherogenicity. Triglyceride (TG)-rich lipoproteins (chylomicron and VLDL) are not considered to be atherogenic but they are related to the metabolism of HDL cholesterol and indirectly related to coronary heart disease (CHD). LDL can of itself be atherogenic but the oxidative products of this lipoprotein are more detrimental. HDL cholesterol has been considered to be a favorable cholesterol. The so-called 'causalist view' claims that HDL traps excess cholesterol from cellular membranes and transfers it to TG-rich lipoproteins that are subsequently removed by hepatic receptors. In the so-called 'noncausalist view', HDL does not interfere directly with cholesterol deposition in the arterial wall but instead reflects he metabolism of TG-rich lipoproteins and their conversion to atherogenic remnants. Approximately 70-80% of the human population shows an effective feedback control mechanism in cholesterol homeostasis. Type of dietary fat has a significant effect on the lipoprotein cholesterol metabolism and atherosclerosis. Generally, saturated fatty acids elevate and PUFA lower serum cholesterol, whereas MUFA have no specific effect. EPA and DHA inhibit the synthesis of TG, VLDL and LDL, and may have favourable effects on some of the risk factors. Phospholipids, particularly lecithin, have an antiatherosclerotic effect. Essential phospholipids (EPL) may enhance the formation of polyunsaturated cholesteryl ester (CE) which is less sclerotic and more easily dispersed via enhanced hydrolysis of CE in the arterial wall. Also, neutral fecal steroid elimination may be enhanced and cholesterol absorption reduced following EPL treatment. Antioxidants protect lipoproteins from oxidation, and cells from the injury of toxic, oxidized LDL. The rationale for lowering of serum cholesterol is the strong association between elevation of plasma or serum cholesterol and CHD. Cholesterol-lowing, especially LDL cholesterol, to the target level could be achieved using diet and combination of drug therapy. Information on the link between cholesterol and CHD has decreased egg consumption by 16-25%. Some clinical studies have indicated that dietary cholesterol and egg have a significant hypercholesterolemic effect, while others have indicated no effect. These studies differed in the use of purified cholesterol or cholesterol in eggs, in the range of baseline and challenge cholesterol levels, in the quality and quantity of concomitant dietary fat, in the study population demographics and initial serum cholesterol levels, and clinical settings. Cholesterol content of eggs varies to a certain extent depending on the age, breed and diet of hens. However, egg yolk cholesterol level is very resistant to change because of the particular mechanism involved in yolk formation. Egg yolk contains a factor of factors responsible for accelerated cholesterol metabolism and excretion compared with crystalline cholesterol. One of these factors could be egg lecithin. Egg lecithin may not be as effective as soybean lecithin in lowering serum cholesterol level due probably to the differences of fatty acid composition. However, egg lecithin may have positive effects in hypercholesterolemia by increasing serum HDL level and excretion of fecal cholesterol. The association of serum cholesterol with egg consumption has been widely studied. When the basal or control diet contained little or no cholesterol, consumption of 1 or 2 eggs daily increased the concentration of plasma cholesterol, whereas that of the normolipemic persons on a normal diet was not significantly influenced by consuming 2 to 3 eggs daily. At higher levels of egg consumption, the concentration of HDL tends to increase as well as LDL. There exist hyper-and hypo-responders to dietary (egg) cholesterol. Identifying individuals in both categories would be useful from the point of view of nutrition guidelines. Dietary modification of fatty acid composition has been pursued as a viable method of modifying fat composition of eggs and adding value to eggs. In many cases beneficial effects of PUFA enriched eggs have been demonstrated. Generally, consumption of n-3 fatty acids enriched eggs lowered the concentration of plasma TG and total cholesterol compared to the consumption of regular eggs. Due to the highly oxidative nature of PUFA, stability of this fat is essential. The implication of hepatic lipid accumulation which was observed in hens fed on fish oils should be explored. Nutritional manipulations, such as supplementation with iodine, inhibitors of cholesterol biosynthesis, garlic products, amino acids and high fibre ingredients, have met a limited success in lowering egg cholesterol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.1899-1907
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• 2013

We investigated the effects of unripe black raspberry water extract (UBR-W) and oxidation-LDL treatment on cholesterol levels. Experiments using an established human hepatocellular carcinoma cell line (HepG2) showed a time-dependent increase in expression of LDL receptor after UBR-W treatment. Expression of LDL receptor-related genes, such as SREBP1 and 2, increased upon UBR-W treatment. However, expression of HDL-related genes was unaffected by UBR-W. HMG-CoA reductase activity was reduced by UBR-W treatment, whereas HMG-CoA mRNA expression significantly increased. In addition, the ApoB/ApoA1 mRNA level, which is a predictor of cardiovascular risk, was reduced in a time-dependent manner by UBR-W treatment. Macrophage-like cells (RAW 264.7) showed increased expression of ox-LDL-related genes, such as CD36, scavenger receptor-A, adipophilin, and PPAR-gamma, upon ox-LDL treatment compared to untreated control cells, and quantitative lipid analysis indicated a dramatic increase in lipid accumulation. However, UBR-W treatment significantly reduced expression of ox-LDL-related genes and largely prevented lipid accumulation. The results indicate that UBR-W mediates a cholesterol-lowering effect via inhibition of cholesterol synthesis and induction of LDL uptake through SREBP.

• Korean Journal of Plant Resources
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• v.26 no.2
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• pp.227-233
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• 2013

This study was carried out to effects of Allium victorials extract on lowering lipid, anti-oxidation and concentration of inflammatory mediators in rats fed high oxidized fat. Concentration of free fatty acid(FFA), triglyceride(TG), total cholesterol and LDL-cholesterol in plasma decreased in the Allium victorials extract groups and plasma HDL-cholesterol concentration revealed a tendency to increase in Allium victorials extract groups. Concentration of total cholesterol and TG in liver showed a tendency to decrease in Allium victorials extract groups. Concentration of thiobarbituric acid(TBARS) in plasma and liver showed a lower values in Allium victorials extract groups than that of control group. Activities of glutathione peroxidase(GSH-Px), superoxide dismutase(SOD) and catalase(CAT) in liver showed a tendency to increase in Allium victorials extract groups. Concentration of nitrogen oxide(NO), ceruloplasmin and ${\alpha}1$-acid glycoprotein in plasma showed a lower values in Allium victorials extract groups than that of control group. These results indicate that the Allium victorials extract have an functional material for lowering lipid, anti-oxidation and anti-inflammatory effect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.507-513
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• 1997

This study was carried out to examine whether kimchi has hypolipidemic effect and to know how it exert lipid-lowering effect in rats. Male Sprague-Dawley rats were fed with kimchi-fee diet, or 3%, or 5%, or 10% kimchi diets for 6 weeks. Plasma cholesterol level was lowered in rats fed all concentrations of kimchi diets, and plasma triglyceride(TG) level was lowered in 10% kimchi diet group compared with that of control significantly(p<0.05). Th intake of kimchi lowered VLDL-cholesterol and VLDL-TG levels, whereas increased HDL-cholesterol level significantly(p<0.05). LDL-cholesterol level was lowered only in 5% kimchi diet group and LDL-TG level was lowered in all kimchi diet groups compared with those of control significantly (p<0.05). the intake of 5% and 10% kimchi diets also lowered the levels of hepatic cholesterol, TG, total lipid, and apolipoprotein B, whereas increased the levels of fecal total fat, cholesterol, TG, and apolipoprotein A-1 significantly(p<0.05). Triiodothyronine(T$_3$) level was elevated in rats fed kimchi diet, whereas thyroxine(T$_4$) level was not affected by kimchi treatment. These observations support that the intake of kimchin in rats loweres plasma and hepatic lipid levels by increasing the excretion of TG and cholesterol through feces, by the elevation of T$_3$ level, and by the altered lipoprotein metabolism.

• Journal of Nutrition and Health
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• v.37 no.5
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• pp.352-363
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• 2004

Lipid-lowering effects of the inulin have been demonstrated in animal, yet attempts to reproduce similar effects in humans have generated conflicting results. In this study, the lipid-lowering potential of inulin and especially its effect on bile acid and neutral sterol excretion were investigated in Korean postmenopausal women. Nineteen postmenopausal women were randomly divided into two groups in a double-blind parallel design and consumed one of two supplements for 12 weeks; placebo of 8g maltodextrins/sucrose mixture (placebo group) or 8g inulin (inulin group). There were no significant changes in body weight during the supplementation period in either inulin or placebo group. Dietary consumption of animal fat in both group tended to decrease after 12 weeks of experiment. Intake of cholesterol was lower in placebo group, whereas the decrease of cholesterol intake in inulin group did not reach statistical significance after 12 weeks. The levels of serum total cholesterol (TC) and LDL-cholesterol (LDL-C) were significantly decreased in both placebo (p＜0.05) and inulin group (p＜0.01) after supplementation for 12 weeks compared with the baseline. The levels of serum triglyceride (TG) and HDL-cholesterol (HDL-C) were not significantly affected by inulin supplements, but atherogenic index (AI) and LDL-C/HDL-C ratio (LHR) as a predictor for coronary heart disease were improved (p＜0.01) significantly after inulin supplementation. Therefore, inulin supplement may decrease the risk of cardiovascular disease via improving blood cholesterol level. Fecal weight and pH were not changed after 12 weeks of supplementation. There were no statistically significant changes for the fecal short-chain fatty acids (SCFAs). In inulin group, fecal deoxycholic acid (DCA) was significantly lowered compared with the baseline (p＜0.05) whereas other bile acids were not changed. During the 12 weeks of intervention, no differences were found in fecal excretion of neutral sterol in the two groups. In summary, dietary inulin decreases serum TC, LDL-C, AI, LHR and lowers excretion of fecal DCA in the Korean postmenopausal women. These results support the use of inulin for reducing risk factors for hyperlipidemic postmenopausal women. However, the exact mechanism (s) responsible for the blood lipid lowering action of inulin including altered fecal bile acid remain to be elucidated.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.2
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• pp.165-173
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• 2006

To investigate the effects of yellow soybean powder on serum lipid level and enzyme activities, male Sprague-Dawley(SD) rats were given hyperlipidemic diets for 6 weeks. Rats(n=8) were divided into three groups consisting the normal group(N), hyperlipidemic diets group(C) and hyperlipidemic diets and yellow soybean powder group(YSP). YSP group lowered triglyceride, total lipid, phospholpid, ester-cholesterol and free-cholesterl than control group. YSP group lowered total-cholesterol, VLDL-cholesterol and LDL-cholesterol but increased HDL-cholesterol of the serum compared to the control group. Athergenic Index(AI) and LHR(LDL-cholesterol/HDL-cholesterol ratio) of YSP group was decreased by control group (p<0.05). On the other hand, glutamic oxaloacetate transaminase(GOT), glutamic pyruvate transaminase (GTP), lactate dehydrogenase(LDHase) and alkaline phosphatase(ALP) enzymes activities were decreased by hyperlipidemic diets group (C). These results suggest that yellow soybean powder fed a lipid lowering effect in serum of rats.

• YAKHAK HOEJI
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• v.44 no.1
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• pp.71-79
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• 2000

Curcumin, the yellow pigment in turmeric, curry and mustard, has anti-inflammatory and anti-carcinogenic activities. In this study; we investigated the hypocholesterolemic and anti-atherogenic effect of curcumin in rabbits. Hypercholesterolemia was induced by feeding high cholesterol diet to male rabbits for 30 days, and the animals were then fed high cholesterol diet containing 0.1% (w/w) or 0.5% (w/w) curcumin for additional 30 days. Supplementation of 0.l% curcumin tended to lower serum total cholesterol and low density lipoprotein (LDL)-cholesterol levels and inhibit serum lipid peroxidation. In the 0.5% curcumin-supplemented group, serum total cholesterol was significantly lowered by 11.7%, LDL-cholesterol by 12.8% and lipid peroxidation by 47.9% compared to the control group. Hepatic cholesterol and triglyceride contents were also significantly lowered by 50.6% and 37.4%, respectively compared to the control group. Lipid staining of the arteries isolated from the curcumin-treated rabbits showed that curcumin significantly decreased formation of fatty streaks and atheromatous plaques on the intima of the arteries. These results demonstrated that curcumin lowered serum cholesterol concentration, hepatic cholesterol and triglyceride contents, and accumulation of cholesterol in the artery These cholesterol lowering effects of curcumin, together with its anti-oxidative and anti-inflammatory activities, may play some important roles in preventing atherosclerosis.

• Korean Journal of Pharmacognosy
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• v.34 no.2 s.133
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• pp.179-184
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• 2003

We have investigated the effect of MeOH extract of the adventious root culture of Panax ginseng on hyperlipidemic rats induced by fat-rich diet. We also analyzed and compared the content ginsenoisdes of the cultured ginsengs by HPLC. After oral administration of the MeOH extract to hyperlipidemic rats for four weeks, the variables including body weight, cholesterol, HDL, LDL, and triglyceride levels in serum were measured. One of the cultured ginseng roots (CBN3) decreased cholesterol and LDL-cholesterol and increased HDL-cholesterol levels in serum. HPLC analysis demonstrated that CBN3 contains more $Rb_1$ and Rd ginsenosides than any other cultured ginsengs and cultivated ginseng. These results suggest that CBN3 with high contents of $Rb_1$ and Rd may be useful in lowering blood cholesterol.

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.2
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• pp.81-87
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• 2016

This study was performed to investigate the cholesterol-lowering effect of liquid extract from Leonurus sibiricus Linne (LS). SD rats were fed atherogenic diet for 6 weeks. During the experimental period, LS liquid extract (3 g/kg and 6 g/kg) was orally given to the rats. The liver weight and levels of total cholesterol, LDL-cholesterol, and triglycerides in serum were significantly increased in rats fed with atherogenic diets. Oral treatment of LS liquid extract to the rats fed atherogenic diet significantly reduced the liver weights and significantly decreased the levels of total cholesterol, LDL-cholesterol, and triglycerides. The level of serum HDL-cholesterol was significantly increased at a high dose group compared with rats fed normal diet chow. These results indicate that LS liquid extract has the potential to restore altered lipid profiles induced by cholesterol rich diets and prevent the development of atheroclerosis.

• The Journal of Korean Medicine
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• v.27 no.2 s.66
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• pp.253-261
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• 2006

Backgrounds : Hyperlipidemia is a major cause of cardiovascular disease (CVD). Lowering serum cholesterol levels could reduce the risk of CVD. Insamsansa-eum (Renshenshanzha-yin, ISE), composed of Ginseng Radix and Crataegii Fructus, is a new medicine developed to treat hyperlipidemia and CVD. Objectives : In this study, we intended to explore the clinical effects of ISE on patients with hypercholesterolemia, and moreover we also compared its effects according to the pattern identification. Methods : Subjects were administered ISE with the dose of 600 mg three times a day for 4 weeks. Patterns of subjects were identified with diagnostic scoring system for Yin-Yang and the condition of Excess-Deficiency before treatment. Serum lipids were measured at baseline and after 4 weeks of medication. Results : ISE lowered total cholesterol(TC), triglyceride(TG), total lipid(TL), phospholipid(PL) and low density lipoprotein cholesterol(LDL) significantly. Compared with the data of our previous study, it was less effective than Atorvastatin but showed equal lipids-lowering effect to Chunghyul-dan (Qingxue-dan, CHD). In Yang pattern group, ISE was less effective in lowering TG and LDL than it was in not-Yang-not-Yinpattern group. On safety assessment, there was no adverse effect, hepatic or renal toxicity. Conclusions : We suggest that ISE is a safe and useful herbal medicine for hypercholesterolemia, and moreover it could be more useful when it is used for patients with not Yang pattern.