• Nutritional Sciences
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• 제6권4호
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• pp.232-238
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• 2003

Cardiovascular disease (CVD) is one of the most common causes of death in elderly Koreans, and HDL-cholesterol is known to have a pivotal role in protecting against CVD. This study was undertaken to study the relationships between plasma HDL-cholesterol levels and dietary, anthropometric, and biochemical factors in elderly Koreans. The 102 subjects, who were over 60 years old, were classified into two groups based on their plasma HDL-cholesterol levels: a risk group with plasma HDL-cholesterol < 40mg/dl in men or HDL-cholesterol < 50mg/d1 in women, and a control group with higher HDL-cholesterol levels. The subjects' mean intakes of energy, calcium, zinc, vitamin A, vitamin $B_2$, vitamin E, and folate did not meet the Korean RDA for elderly people. Vitamin $B_2$ and folate intakes were significantly lower (p<0.l) in the risk group compared to the control group. The consumption of seaweed was significantly lower (p<0.05), and fish intake was 33% lower, in the risk group compared to the control group. Subjects in the risk group showed a higher BMI, waist/hip ratio, triceps skinfold thickness, and % body fat, compared to control subjects. Plasma triglyceride levels and values of the atherogenic index were significantly higher (p<0.00l) in risk group subjects. Significant negative correlations between HDL-cholesterol level and plasma triglyceride level (r= 0.37), and values of the atherogenic index (r=-0.74), were found. In summary, subjects with low levels of HDL-cholesterol were found to have relatively low intakes of vitamin B$_2$, folate, and seaweed, and higher levels of the CVD risk factors: body fat, plasma TG, and AI. These results suggest that plasma HDL-cholesterol levels can be modified by dietary, anthropometric, and hematological means.

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2004년도 춘계학술대회
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• pp.81-81
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• 2004

• 대한수의학회지
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• 제36권1호
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• pp.57-63
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• 1996

Dihydrofolate reductase(DHFR) 억제제는 혈중활성엽산유도체의 농도저하를 초래하는데 이에 대한 기전을 밝히고자 DHFR 억제제의 대표적 약물로서 항암치료에 널리 사용되고 있는 methotrexate를 0.3 및 10mg/kg의 용량으로 랫드에 정맥주사한 후 활성엽산유도체의 담즙배설동태를 검토하였다. 임상적용 용량을 상회하는 용량임에도 불구하고 methotrexate에 의한 환원형엽산유도체의 담즙배설은 유의적 감소를 나타내지 않았다. 이러한 결과는 methotrexate에 의한 엽산유도체의 혈중농도저하가 활성엽산유도체의 담즙배설저하에 직접 관련되지 않는 것을 나타낸다. 따라서 장간순환계가 체내 엽산대사 및 항상성 유지에 중심기구임을 고려해 볼 때 DHFR 억제제에 의한 활성엽산유도체의 혈중농도저하는 담즙배설의 변화에 의한 것 보다는 소화관에 배설된 후 재흡수의 저하에 의해 초래될 가능성이 높은 것으로 사료된다.

• Nutrition Research and Practice
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• 제9권2호
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• pp.144-149
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• 2015

BACKGROUND/OBJECTIVE: The aim of this study was to examine the effect of high dietary methionine (Met) consumption on plasma and hepatic oxidative stress and dyslipidemia in chronic ethanol fed rats. MATERIALS/METHODS: Male Wistar rats were fed control or ethanol-containing liquid diets supplemented without (E group) or with DL-Met at 0.6% (EM1 group) or 0.8% (EM2 group) for five weeks. Plasma aminothiols, lipids, malondialdehyde (MDA), alanine aminotransferase (ALT), and aspartate aminotransferase were measured. Hepatic folate, S-adenosylmethionine (SAM), and S-adenosylhomocysteine (SAH) were measured. RESULTS: DL-Met supplementation was found to increase plasma levels of homocysteine (Hcy), triglyceride (TG), total cholesterol (TC), and MDA compared to rats fed ethanol alone and decrease plasma ALT. However, DL-Met supplementation did not significantly change plasma levels of HDL-cholesterol, cysteine, cysteinylglycine, and glutathione. In addition, DL-Met supplementation increased hepatic levels of folate, SAM, SAH, and SAM:SAH ratio. Our data showed that DL-Met supplementation can increase plasma oxidative stress and atherogenic effects by elevating plasma Hcy, TG, and TC in ethanol-fed rats. CONCLUSION: The present results demonstrate that Met supplementation increases plasma oxidative stress and atherogenic effects by inducing dyslipidemia and hyperhomocysteinemia in ethanol-fed rats.

• Archives of Pharmacal Research
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• 제26권11호
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• pp.979-983
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• 2003

The pharmacokinetic of tolbutamide was studied after the oral administration to normal rabbits or rabbits with mild to medium folate-induced renal failure. The plasma concentrations of tolbutamide were significantly elevated (p<0.05) during 9 to 24 h in rabbits with mild or medium folate-induced renal failure. Consequently, the area under the plasma concentration-time curves (AUC) was significantly higher in mild (p<0.05) and medium (p<0.01) folate-induced renal failure rabbits (i.e., 2906 $\mu$g/mL$.$h for mild renal failure and 4074 $\mu$g/mL$.$h for moderate renal failure) than that in normal rabbits (i.e., 2295 $\mu$g/mL$.$h). The cumulative urinary excretion of tolbutamide was significantly depressed (p<0.05) in medium folate-induced renal failure rabbits (i.e., 3.3 mg) compared with that in normal rabbits (i.e., 5.9 mg). The elimination rate constant (Kel) of tolbutamide was significantly decreased in medium renal failure rabbits (i.e., 0.027 $h^{-1}$) than that in normal rabbits (i.e., 0.044 $h^{-1}$ ); As a result, the terminal half-life of tolbutamide in medium folate-induced renal failure rabbits (i.e., 25.5 h) was significantly longer (p<0.01) than that in normal rabbits (i.e., 15.7 h). The change in pharmacokinetic parameters is consistent with the hypothesis that the alteration is mediated by the depressed metabolic elimination of the drug by the induction of renal failure. Therefore, these observations indicated that the dosage adjustment may be necessary for tolbutamide in patients with renal insufficiency.

• BMB Reports
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• 제37권3호
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• pp.362-369
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• 2004

The human folate receptor (hFR) is a glycosylphosphatidylinositol (GPI) linked plasma membrane protein that mediates delivery of folates into cells. We studied the sorting of the hFR using transfection of the hFR cDNA into MDCK cells. MDCK cells are polarized epithelial cells that preferentially sort GPI-linked proteins to their apical membrane. Unlike other GPI-tailed proteins, we found that in MDCK cells, hFR is functional on both the apical and basolateral surfaces. We verified that the same hFR cDNA that transfected into CHO cells produces the hFR protein that is GPI-linked. We also measured the hFR expression on the plasma membrane of type III paroxysmal nocturnal hemoglobinuria (PNH) human erythrocytes. PNH is a disease that is characterized by the inability of cells to express membrane proteins requiring a GPI anchor. Despite this defect, and different from other GPI-tailed proteins, we found similar levels of hFR in normal and type III PNH human erythrocytes. The results suggest the hypothesis that there may be multiple mechanisms for targeting hFR to the plasma membrane.

• 대한예방한의학회지
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• 제11권1호
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• pp.45-53
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• 2007

Homocysteine is a sulfur amino-acid produced during the metabolism of the essential amino acid methionine. Moderately increased plasma total homocysteine concentration have been implicated as a risk factor for occlusive vascular disease. Smoking is known to be one of the most significant factors leading to elevated plasma homocysteine concentration. However, the main component of a cigarette, nicotine has been not studied whether it is linked directly to the increase of homocysteine concentration in blood. The metabolism of homocysteine is closely linked to that of its cofactors, folate. Here, the effects of nicotine and folic acid on amount of plasma homocysteine were studied. The concentration of homocysteine was increased by about 70% in rat plasma after nicotine treatment for one month. This increased concentration of homocysteine was reduced by about 60% at 6 hours later after folate treatment. Thus, nicotine should be directly involved in increasing the concentration of plasma homocysteine. Also it is suggested that these results can be and applied and used for controlling withdrawal symptoms after stopping smoking as one of oriental medicine formulas.

• Journal of Nutrition and Health
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• 제38권7호
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• pp.495-502
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• 2005

This study was performed to investigate effects of dietary folic acid supplementation on plasma homocysteine levels, thiobarbituric acid reactive substance s (TBARS) level s and liver SAM/SAH ratio in hyperhomocysteinaemia-induced pregnant rats. Forty-two female Sprague-Dawley rats were divided three groups (C: control diet, HFD: $0.3\%$ homocystine and 0 mg folic acid diet, HFS: $0.3\%$ homocystine and 8 mg/kg folic acid diet) according to homocystine and folic acid levels in the diet. They were fed experimental diets for 5 weeks prior to the mating and also during the entire period of pregnancy till gestational day 20. Dietary folic acid supplementation caused a significant decrease in plasma homocysteine levels which had been increased by a homocystine-diet, with a concomitant increase in plasma and liver folate levels. Liver TBARS levels in homocysteine-folic acid-deficient group (HFD) were higher than those in control group. Dietary folic acid supplementation increased hepatic SAM/SAM ratio in homocysteine-folic acid- sopplemetantion group (HFS) when compared to the HFD (p < 0.05). These data suggest that folate depletion and elevated plasma homocysteine may promote oxidative stress in rat livers and influence the remethylation cycle of the homocysteine metabolism detrimentally. In conclusion, dietary folic acid supplementation was found to be effective for lowering plasma homocysteine levels, relieving oxidative stress, and improving the methylation status in the body.

• 한국임상약학회지
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• 제8권1호
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• pp.23-28
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• 1998

The pharmacokinetics of atenolol (25 mg/kg, i.v.) in the folate-induced renal failure rabbits was studied. Renal failure was induced by the i.v. injection of folate (50, 100, and 200 mg/kg). At folate dose of 100 and 200 mg/kg, the serum creatinine concentration (Scr) and blood urea nitrogen (BUN) increased significantly compared with control rabbits. Plasma concentrations and AUC of atenolol increased significantly at folate dose of 100 and 200 mg/kg. The elimination rate constant $(K_{el})$ and total body clearance $(CL_t)$ of atenolol decreased significantly, and half-life ($t_{1/2}$) and mean residence time (MRT) of atenolol increased significantly at folate dose of 100 and 200 mg/kg. The serum creatinine concentration $(S_{cr})$ correlated well (p<0.05) with half-life $(t_{1/2})$ and elimination rate constant $(K_{el})$ of atenolol, as well as BUN with AUC and total body clearance $(CL_t)$ of atenolol.

• Journal of Nutrition and Health
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• 제35권1호
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• pp.37-44
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• 2002

본 연구에서는 20대 초반의 젊은 여성인 일부 여대생을 대상으로 영양소 섭취량. 인체계측, 혈장 호모시스테인 및 혈중 비타민 농도를 분석하여 혈장 호모시스테인 농도와 비타민 영양상태 간의 상관성을 조사하였다. 조사대상자의 평균연령은 22.4세였으며 평균 수축기, 이완기 혈압은 각각 115mmHg, 71.5mmHg였다. 조사대상주중 13%(4명)만이 영양 보충제를 섭취하였고 33%(10명)정도가 월 3회 이상 음주를 하였으며 흡연자는 3%(1명)에 해당하였다. 평균 신장과 체중은 각각 160.9cm. 54.5kg이었으며 BMI는 21.0 체지방률은 24.9%로 모두 정상수준 범위에 해당하였다. 일일 평균 열량 섭취량은 1731.9kcal로 권장량의 86.6%에 해당하는 다소 낮은 수준이었다. 비타민 B$_{12}$의 일일 평균 섭취량은 2.2mg이었으며 비타민 B$_{6}$와 엽산의 일일 평균 섭취량은 각각 0.9mg, 139.8$\mu\textrm{g}$으로 권장량의 58.7%와 55.9%로 나타나 낮은 섭취수준을 보였다. 이들 비타민의 주요 급원 식품으로 비타민 B$_{6}$는 곡류 및 전분류(61.4%), 비타민 B$_{12}$는 육류 및 달걀류(49.0%) 그리고 엽산은 야채 및 과일류 (55.2%)로 조사되었다. 조사대상자의 혈장 호모시스테인의 평균농도는 12.4$\mu$mol/l로 정상범위를 나타내는 5~15$\mu$mol/l에 해당하였으며 전체 조사대상자중 5명은 15$\mu$mol/l이상의 혈장 호모시스테인 농도(15.1~17.8$\mu$mol/l)를 나타내었다. 혈장 비타민 B$_{6}$(PLP)의 평균 농도는 77.5nmol/l로 정상수준인 30nmol/l이상이었으며. 비타민 B$_{12}$의 평균농도 역시 267.4pmol/l로 정상범위인 147.6~664pmol/l에 속하였다. 적혈구와 혈청의 평균 엽산 농도는 각각 736.5nmol/l, 17.1nmol/l였으며 조사대상자 모두 적혈구 엽산의 한계결핍 수준인 315~359nmol/l 이상과 혈청 엽산 농도의 적정 수준인 13.5nmo/l/이상의 양호한 영양상태를 나타내었다. 또한 적혈구와 혈청의 엽산 농도 사이에 유의한 양의 상관성이 있었다 비타민 B$_{6}$, B$_{12}$ 및 엽산의 섭취가 증가할수록 혈장 호모시스테인 함량이 감소하는 경향이 있었으며 이들 비타민의 혈중 농도와 혈장 호모시스테인 농도 사이에도 음의 경향을 나타내었으나 유의한 상관성은 없었다. 엽산 섭취량의 증가에 따라 적혈구와 혈청의 엽산 농도가 증가하는 경향을 나타내었고 비타민 B$_{6}$의 섭취량과 혈중 총 비타민 B$_{6}$의 90%이상을 차지하는 혈장 PLP농도 사이에는 유의한 양의 상고나성이 있었다. 혈중 호모시스테인 농도는 질병의 위험요인으로서 뿐 아니라 대사적으로 밀접하게 연관된 비타민 영양상태의 biomarker로서도 그 영향력이 크다고 할 수 있다. 따라서 성별에 다른 다양한 연령집단에서 건강한 일반인과 심혈관계 질환자 등을 대상으로 호모시스테인과 비타민 영양상태에 대한 연구가 체계적으로 이루어 져야 할 것이다.