• Preventive Nutrition and Food Science
• /
• 제22권2호
• /
• pp.90-99
• /
• 2017

Fish muscles are classified into white and red muscles, and the chemical composition of the two fish muscles have many differences. Few reports have assessed the health-promoting functions of white fish muscle proteins (WFP) and red fish muscle proteins (RFP). We therefore evaluated the mechanisms underlying the alteration of lipid profiles and cholesterol metabolism following the intake of WFP prepared from cod and RFP prepared from light muscles of tuna. Male Wistar rats were divided into six dietary groups: casein (23%), WFP (23%), and RFP (23%), with or without 0.5% cholesterol and 0.1% sodium cholate. Compared to the WFP-containing diet, the RFP-containing diet supplemented with cholesterol and sodium cholate significantly increased serum and liver cholesterol contents. However, in the RFP groups, an alteration in cholesterol metabolism including an increased tendency to excrete fecal sterols and hepatic cholesterol $7{\alpha}$-hydroxylase was related to the reduction of hepatic cholesterol contents. This phenomenon might be related to the tendency of an increased food intake in RFP-containing diets. These results highlight the differential effects of WFP and RFP on serum and liver lipid profiles of Wistar rats fed non-cholesterol- or cholesterol-containing diets under no fasting condition.

• Journal of Microbiology and Biotechnology
• /
• 제17권4호
• /
• pp.655-662
• /
• 2007

This study examined the effects of Lactobacillus acidophilus ATCC 43121 (LAB) on cholesterol metabolism in hypercholesterolemia-induced rats. Four treatment groups of rats (n=9) were fed experimental diets: normal diet, normal $diet+LAB(2{\times}10^6\;CFU/day)$, hypercholesterol diet (0.5% cholesterol, w/w), and hypercholesterol diet+LAB. Body weight, feed intake, and feed efficiency did not differ among the four groups. Supplementation with LAB reduced total serum cholesterol (25%) and VLDL+IDL+LDL cholesterol (42%) in hypercholesterol diet groups, although hepatic tissue cholesterol and lipid contents were not changed. In the normal diet group, cholesterol synthesis (HMG-CoA reductase expression), absorption (LDL receptor expression), and excretion via bile acids (cholesterol $7{\alpha}-hydroxylase$ expression) were increased by supplementation with LAB, and increased cholesterol absorption and decreased excretion were found in the hypercholesterol diet group. Total fecal acid sterols excretion was increased by supplementation with LAB. With proportional changes in both normal and hypercholesterol diet groups, primary bile acids (cholic and chenodeoxycholic acids) were reduced, and secondary bile acids (deoxycholic and lithocholic acids) were increased. Fecal neutral sterol excretion was not changed by LAB. In this experiment, the increase in insoluble bile acid (lithocholic acid) reduced blood cholesterol level in rats fed hypercholesterol diets supplemented with LAB. Thus, in the rat, L. acidophilus ATCC 43121 is more likely to affect deconjugation and dehydroxylation during cholesterol metabolism than the assimilation of cholesterol into cell membranes.

• 한국식품영양과학회지
• /
• 제34권5호
• /
• pp.573-580
• /
• 2005

수용성 식이섬유의 섭취는 혈청 콜레스테롤 저하효과가 있으며 , 그 작용기 작으로는 수용성 식이섬유의 점성으로 인한 콜레스테롤과 담즙산 흡수저해, 대장내 미생물 발효로 생성 된 단쇄지방산에 의한 콜레스테롤 합성률 변경 및 담즙산 합성증가 등으로 설명되어진다. 그러나 명확한 작용기전은 규명 되지 않았다. 본 연구에서는 간세포 핵내의 CYP7A1의 발현에 호르몬과 식이섬유의 발효로 생성된 단쇄지방산이 미치는 영향을 알아보았다. 사람의 간세포(HepG2 세포)의 배양배지에 insulin, dexamethasone 및 triiodothyronine을 각각 $1\;{\mu}M$ 투여하고 24시간 배양하였다. Semi-quantitative RT-PCR기법에 의해 CYP7A1 mRNA발현을 측정한 결과, dexamethasone에서 가장 높아 $173\%$의 증가를 나타내었고, 그 다음으로 insulin에서 $150\%$, triiodothyronine 에서 $141\%$의 증가를 나타내었다. 이처럼 transient transfection을 하지 않은 HepG2 세포에서 생리적 조절자로 알려진 insulin, dexamethasone 및 triiodothyronine이 CYP7A1의 발현을 모두 증가시킨다는 결과는 본 연구에서 처음으로 규명하며, rat gene and/or human gene 발현이 다르게 조절됨을 제안한다. 단쇄지방산에 의한 HepG2 세포에서의 CYP7A1 유전자의 발현 정도를 측정하기 위해서 actetate, propionate 및 butyrate를 각각 1 M농도로 24시간 동안 배양한 결과, 모든 단쇄지방산이 CYP7A1의 발현을 증가시켰다. Acetate와 propionate는 유사한 효과를 나타내어 대조군에 비하여 1.8배의 증가를 나타내었으며 , butyrate는 1.5배의 증가를 보였다. 이상의 결과는 수용성 식이섬유 섭취시 나타나는 콜레스테롤 저하 효과는 수용성 식이섬유의 대장 발효가 대장을 자극함으로써 내인성 호르몬의 변화를 통해서 나타나거나 대장내 발효산물인 actetate, propionate 및 butyrate 등이 흡수되어 간에서의 CYP7A1의 up-regulation에 의한 담즙산 배설증가에 따른 결과로 설명할 수 있을 것이다. 단쇄지방산의 CYP7A1 발현에 미치는 작용은 acetate와 propionate가 butyrate보다 큼을 알 수 있었다.

• Nutrition Research and Practice
• /
• 제12권4호
• /
• pp.298-306
• /
• 2018

BACKGROUND/OBJECTIVES: Obesity is a global health problem of significant importance which increases mortality. In place of anti-obesity drugs, natural products are being developed as alternative therapeutic materials. In this study, we investigated the effect of Brassica juncea L. leaf extract (BLE) on fat deposition and lipid profiles in high-fat, high-cholesterol diet (HFC)-induced obese rats. MATERIALS/METHODS: Male Sprague-Dawley rats were divided into four groups (n = 8 per group) according to diet: normal diet group (ND), high-fat/high-cholesterol diet group (HFC), HFC with 3% BLE diet group (HFC-A1), and HFC with 5% BLE diet group (HFC-A2). Each group was fed for 6 weeks. Rat body and adipose tissue weights, serum biochemical parameters, and tissue lipid contents were determined. The expression levels of mRNA and proteins involved in lipid and cholesterol metabolism were determined by reverse transcription polymerase chain reaction and western blot analysis, respectively. RESULTS: The HFC-A2 group showed significantly lower body weight gain and food efficiency ratio than the HFC group. BLE supplementation caused mesenteric, epididymal, and total adipose tissue weights to decrease. The serum levels of triglyceride, total cholesterol, and low-density lipoprotein cholesterol were significantly reduced, and high-density lipoprotein cholesterol was significantly increased in rats fed BLE. These results were related to lower glucose-6-phosphate dehydrogenase, acetyl-coA carboxylase, and fatty acid synthase mRNA expression, and to higher expression of the cholesterol $7{\alpha}$-hydroxylase and low density lipoprotein-receptor, as well as increased protein levels of peroxisome proliferator-activated receptor ${\alpha}$. Histological analysis of the liver revealed decreased lipid droplets in HFC rats treated with BLE. CONCLUSIONS: Supplementation of HFC with 3% or 5% BLE inhibited body fat accumulation, improved lipid profiles, and modulated lipogenesis- and cholesterol metabolism-related gene and protein expression.

• 한국식품영양과학회:학술대회논문집
• /
• 한국식품영양과학회 2001년도 International Symposium on Food,Nutrition and Health for 21st Century
• /
• pp.61-68
• /
• 2001

Soybean, rice and nuts are the staple foods in South East Asia. In order to clarify the function of these foods in relation to coronary heart diseases, we have done a series of experiments using animals and humans. Soybean protein preparations (SPI) in comparison with an animal protein, casein (CAS), resulted in reducing atherosclerotic lesion development in apolipoprotein (apo) E deficient mice that develop an advanced lesion similar to that in humans. This action was attributed to the protein, since the ethanol-extracted SPI (EE-SPI), from which isoflavones and saponins removed, lowered the lesion development in apo E-deficient mice. However, The EE-SPI, compared to the SPI, resulted in a decrease of mRNA for key proteins of cholesterol metabolism (low density lipoprotein receptor and cholesterol 7$\alpha$-hydroxylase) in hypercholesterolemic rats, followed by an elevation of the serum cholesterol level, indicating a contribution of isoflavones to the serum cholesterol level. Rice protein (RPI) was also effective to lower the lesion development in apo E deficient mice. Both the SPI and RPI led to an increased level of the serum NOiN03, metabolites of NO. This effect appeared to be attributed to their high content of arginine. Besides, C57BL/6J mice fed a diet containing whole grain rice had an elevation of the serum high-density lipoprotein cholesterol. Furthermore, rice bran oil and the unsaponifiable fraction that is rich in plant sterols were effective to lower serum cholesterol levels in hypercholeserolemic rats. Finally, we tested if walnuts consumption would be hypocholesterolemic for Japanese. A diet containing walnuts effectively lowered the serum total and low density lipoprotein cholesterol in Japanese men and women. These animal and human experiments would be relevant to advocate publics to keep consuming diets including soybean, rice and nuts for their healthful life.

• Food Science and Biotechnology
• /
• 제16권4호
• /
• pp.584-589
• /
• 2007

The effect of water extract of adzuki beans on acetaminophen-altered lipid metabolism was examined in rats. Control group of rats was fed a basal diet, another group of rats was fed 0.5% acetaminophen (APAP group), and a third group of rats was fed 0.5% acetaminophen plus 5% adzuki bean extract (ABE group) for 4 weeks. Serum total and HDL cholesterol levels in the APAP group were significantly lower than those in the control and ABE groups. Hepatic cholesterol $7{\alpha}-hydroxylase$ and fatty acid synthase mRNA levels in the APAP and ABE groups were significantly higher and lower than in the control group, respectively. Hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase mRNA level in the APAP group was significantly lower than in the control group, whereas that in the ABE group was significantly higher than in the APAP group. These results indicate that adzuki bean extract may improve the acetaminophen-altered serum lipid metabolism in rats.

• 한국식품영양과학회지
• /
• 제21권5호
• /
• pp.496-501
• /
• 1992

간세포내 두가지 microsome효소인 HMG-CoA reductase와 cholesterol-$7{\alpha}$-hydroxylase는 콜레스테롤 합성과 담즙산으로의 분해의 조절효소임은 이미 알려진 사실이다. 본 실험에서는 콜레스테롤의 대사산물인 4종류 담즙산들이 간세포내의 콜레스테롤 합성 및 HMG-CoA reductase활성에 미치는 효과를 조사하였다. 간세포의 배양에서 간세포로의 담즙산 흡수는 배지내 농도(1mM~10mM)와 배양시간(1/2~3hr)의 차이에 따라 비례적으로 증가하였다. 콜레스테롤 합성저해에 대한 담즙산의 효과는 배지내 담즙산의 농도 및 배양시간에 따라 크게 감소하였다. 분리시킨 microsome내 HMG-CoA reductase의 활성에 대한 담즙산의 저해효과는 insulin 투여에 의하여 효소활성을 촉진시킨 경우에서도 뚜렷하였으며 콜레스테롤 합성 역시 저하되었다. 분리시킨 간세포막 내 $Na^+$,$K^+$-ATPase의 활성은 1.8~2.5mM정도의 배지내 담즙산 농도까지 증가함을 보였으나 cholic acid 흡수는 상기 효소의 활성에 거의 영향을 주지 않는 것으로 나타났다. 이러한 이유는 아직 불분명하나 1차 대사산물인 cholic acid의 흡수는 단순확산에 의한 것으로 사료되며 이에 대한 더 많은 연구가 요구된다.

• 한국식품영양과학회지
• /
• 제42권6호
• /
• pp.861-868
• /
• 2013

유전적으로 제2형 당뇨병이 유발되는 db/db 생쥐에 OF를 5% 수준으로 4주간 급여한 결과 지방 대사를 개선시켜, 혈장 총콜레스테롤, LDL-콜레스테롤, VLDL-콜레스테롤과 중성지방을 유의적으로(p<0.05) 감소시켰고, HDL-콜레스테롤은 유의적인 차이를 보이지 않았다. 혈장 총콜레스테롤의 감소는 간에서 HMG-CoA-R의 감소에 의한 콜레스테롤의 생성이 줄어든 것이고, 또한 콜레스테롤을 담즙산으로 합성하는 CYP7A1을 증가시켜 콜레스테롤을 담즙산의 형태로 배설시켰기 때문이다. 이 결과 분변 중 담즙산의 함량이 증가하였다. LDL-콜레스테롤의 감소는 LDL-콜레스테롤을 세포로 이동시켜 분해를 촉진하는 LDL-R의 증가로 확인할 수 있었다. db/db mice에서는 비만뿐 아니라 심각한 지방간이 유발되는데 OF의 급여로 AST와 ALT를 낮추어 간세포의 파괴를 완화시켰으며, 간 조직의 H&E 염색 소견에서도 지방간의 완화를 확인할 수 있었다. 또한 대조군으로 C57 생쥐에게 5% 수준으로 OF를 급여한 결과 OF를 급여하지 않은 대조군과 OF를 급여한 실험군의 혈장 중성지방, 총 콜레스테롤, HDL-콜레스테롤, LDL-콜레스테롤, VLDL-콜레스테롤, AST와 ALT 함량의 차이가 없었으며, 간조직 관찰에서도 차이를 나타내지 않았다. 이상의 결과를 종합할 때, OF는 당뇨병이 유발되지 않은 정상혈당의 생쥐에서는 지질대사에 아무런 영향을 주지 않았으며, 제2형 당뇨병인 db/db mice의 당뇨병 합병증인 지질대사 이상을 개선하는데 효과가 있는 것으로 사료되며, OF의 어떤 성분이 이와 같은 효과를 나타냈는지 보다 구체적인 성분 분석과 세부적인 연구를 통한 확인이 필요하다고 사료된다.

• Preventive Nutrition and Food Science
• /
• 제4권3호
• /
• pp.188-192
• /
• 1999

To study effects of methanol extract of prosomillet on lopid metabolism , five groups of male Sprang-Dawley rats weighing 116$\pm$9 g were fed test diets for four weeks. The five diets consisted of one low fat(5% w/w) diet containing starch as carbohydrate source(normal) and four high fat diets(15% w/w) containing 40.5%(w/w)sucrose(control) and additional 80% nethanol extractof prosomillet at the levels of 0.3% and 1%(w/w) or prosomillet powder at the level of 20%(w/w). Serum level of total cholesterol was a little higher but that of triglyceride was 41% lower in 20% (w/w) prosomillet powder group than in the control group. The cholesterol levels of two Liver cholesterol levels were lower and phospolipid levels higher in all three prosomillet powder group . Fecal excretionof bile acid was most increased in the prosomillet powder group among all five test groups. Acitivity of liver microsomal 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase was significantly lower in 0.3% methanol extract fed group than the control and also appeared to be reduced in 1% extract fed one, wherease those of 20 cholesterol 7$\alpha$-hydroxylase were not different among the five groups. Activities of liver cytosilic glucose-6-phosphate dehydrogenase(G6PDH) and malic enzyme were decreased in 0.3% prosomillet methanol extract and 20% powder groups. The results indicate that in addition to fiber, certain active components in prosomillet have potential to exert hypolipidemic effects via regulating hepatic cholesterogenesis and lipogenesis.

• Fisheries and Aquatic Sciences
• /
• 제20권9호
• /
• pp.22.1-22.6
• /
• 2017

The antihyperlipidemic and antioxidant activities of dietary supplementation of sea tangle from Goseong and the alginate-free residue of sea tangle were investigated in Sprague Dawley rats treated with a high-fat diet, streptozotocin, poloxamer 407, and bromobenzene. The alginate-free residue of Goseong sea tangle induced a significant reduction in triglycerides and total cholesterol levels, as well as a significant increase in high-density lipoprotein cholesterol levels. Alginate-free Goseong sea tangle residue reduced the activities of the phase I enzymes aminopyrine N-demethylase and aniline hydroxylase, which had been increased by intraperitoneal injection of bromobenzene. Pretreatment with Goseong sea tangle residue prevented a bromobenzene-induced decrease in epoxide hydrolase activity. Bromobenzene reduced hepatic glutathione content and increased hepatic lipid peroxide levels. Pretreatment with alginate-free Goseong sea tangle residue prevented lipid peroxidation induced by bromobenzene, but pretreatment with Goseong sea tangle did not. These results suggest that Goseong sea tangle residue exerted antihyperlipidemic and antioxidant activities that were higher than those induced by alginate-containing sea tangle. Therefore, the alginate-free residue may contain physiologically unknown active components, other than alginic acid, which may potentially be used to prevent hyperlipidemic atherosclerosis.