• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.5
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• pp.580-593
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• 1992

Cholesterol have many essential functions as a component of cellular and subcellular membranes, metabolic precursor of bile acids and steroid hormones, and obligatory part of the metabolic systems involved in DNA synthesis and cell division. These essential funtions demand a continuous and appropriate supply of cholesterol to the tissues. Body cholesterol pool is maintained by the balance of acquirement from diets, de novo synthesis, and excretion either as bile acids or neutral steroids. In these metabolic process, cholesterol biosynthesis is controlled by the change in the activity of 3-hydroxy-3methylglutaryl coenzyme A (HMG-CoA) reductase. Under most physiological or nutritional situations, the activity of this enzyme is adroitly regulated to maintain tissue cholesterol balance. Excess cholesterol accumulation in the cells induces the decrease in the number of LDL-receptor, followed by the increase in the level of serum LDL-cholesterol. Increase in the level of serum cholesterol appears to be an important determinant for the incidence of the coronary heart disease. Dietary intervention may be helpful in alleviating an increase in the level of serum cholesterol or body cholesterol pool.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.526-534
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• 2013

This study was conducted to examine the effects of Opuntia ficus-indica complex (OF) on the lipid metabolism, bile acid in feces, alanine aminotransferase (ALT) activity, aspatate aminotransferase (AST) activity, composition of urine and expression of cholesterol related mRNA in streptozotocin (STZ)-induced diabetic rats. Thirty two male Sprague-Dawley rats were randomly divided into non-diabetic control (NC), diabetic control (DC), diabetic OF of 2% (OF-2) and diabetic OF of 5% (OF-5), then each group was fed for 3 weeks. Plasma total cholesterol, non-esterified fatty acids (NEFA), total cholesterol, low density lipoprotein (LDL), very low density lipoprotein (VLDL) were decreased significantly (p<0.05) in OF-5 group compared to DC, but high density lipoprotein (HDL) was not changed. AST and ALT were also reduced and bile acid excretion was improved. Composition of urine in OF-5 was almost same in NC. The expression of cholesterol $7{\alpha}$-hydroxylase (CYP7A1), 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA-R), Low density lipoprotein receptor (LDL-R) mRNA indicated that feeding OF have the effects of cholesterol decreation in plasma by synthesis of bile acid from cholesterol. These results provide experimental evidence about improved lipid metabolism of the OF feeding in the STZ-induced diabetic rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.314-318
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• 1997

This study was performed to examine the effects of Meju supplementation to high cholesterol diet on lipid metabolism in rats. Male Sprague-Dawley rats were divided into two groups(Steamed soybean, Meju) and were fed with 0.5% cholesterol diet. Serum and liver lipid profiles and fecal bile acids excretion were examined after four weeks of experimental diet. Food intake, weight gain and liver weight were not significantly different between the two groups. Total cholesterol concentrations in serum was significantly lower in Meju group compared to steamed soybean group(p＜0.05). HDL-cholesterol, triglyceride, phospholipids and nonestrified fatty acid concentrations in serum were not significantly different between the two groups. Cholesterol, triglyceride, and phospholipids concentrations in liver were not significantly different between the two groups. Fecal bile acid excretion were markedly higher in Meju groups than the group fed steamed soybean(p＜0.05). These results suggest that the cholesterol lowering effect by Meju supplementation might be resulted from the modulation of fecal bile acid excretion in rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.906-912
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• 2003

The study was conducted to investigate the effect of Saengshik supplementation on lipid metabolism in rats fed high cholesterol diets. Male Spraque-Dawley rats were administrated 1% cholesterol to induce hypercholesterolemia and were fed on diet containing Saengshik (30%, w/w). Serum and liver lipid profiles and fecal bile acids excretion were examined after 7 weeks of experimental diet. The feeding of diet containing 30% Saengshik significantly decreased total cholesterol (TC) contents in liver and plasma. Since cholesterol was balanced by entero-hepatic circulation through bile acid synthesis and reabsorption, inhibition of bile acid re-uptake in intestine decreases total cholesterol in liver and blood. In this point, significant increament of fecal bile acid excretion in Shaengshik group decreased TC and improved hypercholesterolemia. Also plasma high density lipoprotein-cholesterol (HDL-C) decreasing risk for coronary heart disease in Saengshik supplemented group was significantly higher than control group, whereas low-density lipoprotein-cholesterol (LDL-C) accumulation in arterial vessel wall was significantly lower than control group. In this result, we supposed that supplementation of Saengshik, uncooked natural food, may improve hypercholesterolemia through increment of cholesterol excretion.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.317-334
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• 2002

Ginsenosides are metabolized (deglycosylated) by intestinal bacteria to active forms after oral administration. 20(S)-Protopanaxadiol $20-O-{\beta}-D-glucopyranoside$ (M1) and 20(S)-protopanaxatriol (M4) are the main intestinal bacterial metabolites (IBMs) of protopanaxadiol- and protopanaxatriol-type glycosides. M1 was selectively accumulated into the liver soon after its intravenous (i.v.) administration to mice, and mostly excreted as bile; however, some M1 was transformed to fatty acid ester (EMl) in the liver. EM1 was isolated from rats in a recovery dose of approximately $24mol\%.$ Structural analysis indicated that EM1 comprised a family of fatty acid mono-esters of M1. Because EM1 was not excreted as bile as Ml was, it was accumulated in the liver longer than M1. The in vitro cytotoxicity of M1 was attenuated by fatty acid esterification, implying that esterification is a detoxification reaction. However, esterified M1 (EM1) inhibited the growth of B16 melanoma more than Ml in vivo. The in vivo antitumor activity paralleled with the pharmacokinetic behavior. In the case of M4, orally administered M4 was absorbed from the small intestine into the mesenteric lymphatics followed by the rapid esterification of M4 with fatty acids and its spreading to other organs in the body and excretion as bile. The administration of M4 prior to tumor injection abrogated the enhanced lung metastasis in the mice pretreated with 2-chloroadenosine more effectively than in those pretreated with anti-asialo GMl. Both EM1 and EM4 did not directly affect tumor growth in vitro, whereas EM1 promoted tumor cell lysis by lymphocytes, particularly non-adherent splenocytes, and EM4 stimulated splenic NK cells to become cytotoxic to tumor cells. Thus, the esterification of IBM with fatty acids potentiated the antitumor activity of parental IBM through delay of the clearance and through immunostimulation. These results suggest that the fatty acid conjugates of IBMs may be the real active principles of ginsenosides in the body.

• Journal of Korean Medical Science
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• v.33 no.51
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• pp.324.1-324.6
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• 2018

Oxysterol $7{\alpha}$-hydroxylase deficiency is a very rare liver disease categorized as inborn errors of bile acid synthesis, caused by CYP7B1 mutations. As it may cause rapid progression to end-stage liver disease even in early infancy, a high index of suspicion is required to prevent fatal outcomes. We describe the case of a 3-month-old boy with progressive cholestatic hepatitis and severe hepatic fibrosis. After excluding other etiologies for his early liver failure, we found that he had profuse urinary excretion of $3{\beta}$-monohydroxy-${\Delta}^5$-bile acid derivatives by gas chromatography/mass spectrometry analysis with dried urine spots on filter paper. He was confirmed to have a compound heterozygous mutation (p.Arg388Ter and p.Tyr469IlefsX5) of the CYP7B1 gene. After undergoing liver transplantation (LT) from his mother at 4 months of age, his deteriorated liver function completely normalized, and he had normal growth and development until the current follow-up at 33 months of age. We report the first Korean case of oxysterol $7{\alpha}$-hydroxylase deficiency in the youngest infant reported to undergo successful living donor LT to date.

• Preventive Nutrition and Food Science
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• v.18 no.3
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• pp.210-213
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• 2013

The aim of this study was to investigate the effects of isolated protein from white rice on lipid metabolism in a hypercholesterolemic animal model. Male Sprague-Dawley rats were divided into three groups and fed either a normal diet or a high-cholesterol diet (HCD) containing either casein or isolated rice protein for 4 weeks. Compared with rats fed a HCD with casein, the total cholesterol (TC) level in the plasma was significantly reduced in the rats fed rice protein. However, no significant differences were observed in the triglycerides, high-density lipoprotein (HDL), and glucose levels among the experimental groups. Hepatic total lipids and TC levels were significantly decreased by supplementation with rice protein. In addition, rice protein significantly increased the levels of TC and bile acids in the feces. These results suggest that rice protein may improve HCD-induced hypercholesterolemia by enhancing fecal excretion of cholesterol.

• Molecules and Cells
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• v.44 no.2
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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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• v.29 no.3
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• pp.296-306
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• 1996

The ultimate aim of this study is to find high-fiber sources among Korean common foods and to develop a high-fiber supplement which can be useful in the therapeutic diet for the diabetic patients. For this purpose the effect of four kinds of seaweeds(mixture of purple laver & sea lettuce : MPS, sea tanle : ST, sea mustard : SM, agar agar : AA) on the glucose and lipid mtabolism were examined. Seven groups of normal and streptozotocin-induced diabetic rats were fed dietary fiber-free control diet or one of experimental diets containing 7% of one of four seaweeds for six weeks. The effects of seaweeds were campared with the effects of fiber-free diet or pectin diet. ST, SM, and AA showed a tendency of improving glucose tolerance improvement by those seaweeds, however, was less than that by pectin. MPS was found to possess a serum cholesterol-lowering effect which is comparable to that of pectin. All the supplementations of seaweeds induced significant increase in fecal steroids excretion. The amounts of fecal cholesterol excretion follwing in feeding of MPS and SM were as high as the level cause by pectin. The excretion of bile acids in the MPS group was much higher than that in the pectin group. Based on its effects of alleviating the diabetic symptoms in the previous study and of improving the glucose tolerance, sea mustard seems to have a benefical effect on glucose metabolism. The serum cholesterol-lowering effect of MPS possibly due to the significant increase in fecal steroids excretion suggests that MPS may be effective in improving abnormalities of lipid metabolism. Therefore, sea tangle and mixture of purple laver & sea lettuce seem to be promising as an effective source of high-fiber supplement for the diabetic patients.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.109-120
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• 1993

Mechanisms for the hypocholesterolemic effetcs of $\beta$-glucan remain unclear. Rats were divided into 3 groups; normal control group, atherogenic group(oral administration of cholesterol 40 mg/kg/day and vitamin $D_2$320,000 IU/kg/day),${\beta}$-glucan treatment group(oral administration of atherogenic treatment and ${\beta}$-glucan 0.135 g/kg/day). The ${\beta}$-glucan treatment group showed moderate increases of serum lipids concentration compared with atherogenic group. In histopathological examination, aortas showed no critical lesions. The total fecal neutral sterols and bile acids excreted for 6 days was increased compared with both normal and atherogenic group. These result\ulcorner suggest that mechanisms for the hypocholesterolemic effect of ${\beta}$-glucan on rats were due to the inhibition of cholesterol absorption in the intestinal lumen and acceleration of cholesterol catabolism in the liver.