低总胆固醇与年轻人脑出血

脑出血是一种常见的严重威胁人类生命的疾病。低总胆固醇与脑出血关系最初报道于日本人群,补充食物中的胆固醇可以降低脑出血的发病率。此后美国有研究予以证实,但近年来也有阴性报道。国内低胆固醇与脑出血关     

Efficacy of diet and exercise in the reduction of serum cholesterol and triglyceride in free-living adult males.

Young males with levels of serum cholesterol or triglyceride in the upper quartile of the distribution for volunteers tested, participated in a program designed to determine the effect of diet and exercise on serum lipids. Dietary modifications involved caloric restriction superimposed on either the National Institutes of Health (NIH) recommendations for type II or IV hyperlipoproteinemia, as appropriate, or superimposed on a fat-controlled regimen in which fat of an unspecified nature was restricted to 30% of total calories. Participants with elevated levels of cholesterol responded significantly better when instructed in the diet meeting NIH criteria, 21% change in cholesterol, than when instructed in a diet controlled in fat, 11% change in cholesterol. For those with elevated levels of triglyceride, the NIH type IV diet was no more effective at the end of 6 months than the diet controlled in fat where caloric restriction was a part of both dietary regimens. The mean change in triglyceride for this group was 32%. Those with elevated levels of both cholesterol and triglyceride were less amenable to change than those with a single hyperlipidemia. For some diagnostic types, the results were suggestive of a beneficial effect of exercise in addition to diet in accelerating or maintaining reductions in serum lipids.     

Beta-carotene serum response in young and elderly females

This study was designed to investigate the effects of aging and food intake on the serum beta-carotene (BC) response curve in humans. Ten elderly (71 +/- 4 years) and 17 young (28 +/- 7 years) healthy females were given 15 mg BC with a semi-solid test meal devoid of BC and vitamin A. All the elderly and 10 young subjects (control A) received a test meal of 500 kcal while the remaining 7 young subjects (control B) were given 700 kcal. Subsequently, blood was drawn hourly for 8 h and again at 24 and 48 h. Serum carotenoids and retinoids were measured by HPLC and triglycerides (TG) and cholesterol by enzymatic methods. Small intestinal transit time was determined in the elderly and in control group A by a breath hydrogen test following ingestion of lactulose (12 g) with the test meal. The area under the absorption curve (AUC) of serum BC over the first 8 h was higher in the elderly subjects than in either control group A or B (P less than 0.001). The slopes of the BC and TG curves were significantly higher as compared to control A, but similar to control B. There was a positive correlation between the ascending slopes of the BC and TG absorption curves of all groups (P less than 0.001). The AUC of the retinyl ester serum response of the elderly group was greater than that of control A (P less than 0.001). The slope of this curve was steeper (P less than 0.01) in the elderly group as compared to control A, but was similar to control B. Intestinal transit time was similar in all groups. In young subjects, the larger test meal of control group B appeared to increase the rate of absorption of BC. These data indicate that the rate of intact BC absorption and its conversion to retinyl esters may be enhanced in old age as compared to younger subjects receiving the same amount of food. Age-related alterations of enterocytes and the intestinal lumen could account for this phenomenon.     

Injectable contraceptive, DMPA, serum HDL cholesterol and heart infarct

In 23 women who had used the injectable contraceptive depot medroxyprogesterone acetate (DMPA) for at least 1 year, the mean serum high-density lipoprotein cholesterol (HDL-C) level was distinctly lower than in 23 women carrying an IUD. The high serum DMPA levels during the 1st few weeks after a subsequent DMPA injection, and the low levels 12 weeks after the injection were found to be associated with the same (low) serum HDL-C level. For this reason, a fall in the serum HDL-C level in DMPA users is probably not a direct effect of the DMPA, but rather an indirect effect of the diminished production of endogenous estrogens in the ovaries of DMPA users. Though the investigation does not justify definite conclusions, it appears advisable not to prescribe DMPA to women with an increased risk of atherosclerosis and myocardial infarction. (author's)     

Relation of alcohol, physical activity, dietary fat and smoking to serum HDL and total cholesterol in young Finnish men

The study was based on 471 men, aged 19 to 20 years, who started their compulsory military service in three military bases in Southwest, Southeast and Northern Finland in February 1982. The data were gathered by means of self-administered questionnaires. A fasting venous blood specimen was taken to determine serum HDL and total cholesterol, gamma-glutamyltransferase and thiocyanate. In this cross-sectional study a few variables based on the self-administered questionnaire explained 8% and 7% of the variation in serum HDL and total cholesterol, respectively. Our results show that easily measurable behavioural factors do contribute to serum HDL and total cholesterol levels in young men. In our study the impact of alcohol consumption on serum HCL cholesterol was greater than in most previous studies. Our findings give additional support to the hypothesis that even a very modest amount of regular physical exercise has the effect of increasing the serum HDL cholesterol level.     

A single daily dose of soybean phytosterols in ground beef decreases serum total cholesterol and LDL cholesterol in young,mildly hypercholesterolemic men

BACKGROUND: Renal insufficiency is associated with altered vitamin B-6 metabolism. We have observed high concentrations of 4-pyridoxic acid, the major catabolite of vitamin B-6 metabolism, in plasma during renal insufficiency. OBJECTIVE: The objective was to evaluate the renal handling of 4-pyridoxic acid and the effects of renal dysfunction on vitamin B-6 metabolism. DESIGN: We measured the renal clearance of 4-pyridoxic acid and creatinine in 17 nonpregnant, 17 pregnant, and 16 lactating women. We then examined the influence of vitamin B-6 or alkaline phosphatase activity on the ratio of 4-pyridoxic acid to pyridoxal (PA:PL) in plasma in 10 men receiving a low (0.4 mg pyridoxine.HCl/d) or high (200 mg pyridoxine.HCl/d) vitamin B-6 intake for 6 wk, in 10 healthy subjects during a 21-d fast, in 1235 plasma samples from 799 people screened for hypophosphatasia, and in 67 subjects with a range of serum creatinine concentrations. RESULTS: Renal clearance of 4-pyridoxic acid was 232 +/- 94 mL/min in nonpregnant women, 337 +/- 140 mL/min in pregnant women, and 215 +/- 103 mL/min in lactating healthy women. These values were approximately twice the creatinine clearance, indicating that 4-pyridoxic acid is at least partially eliminated by tubular secretion. Elevated plasma creatinine concentrations were associated with marked elevations in 4-pyridoxic acid and PA:PL. PA:PL was not affected by wide variations in vitamin B-6 intake or by the wide range of pyridoxal-P concentrations encountered while screening for hypophosphatasia. CONCLUSIONS: Plasma 4-pyridoxic acid concentrations are markedly elevated in renal insufficiency. Plasma PA:PL can distinguish between increases in 4-pyridoxic acid concentrations due to increased dietary intake and those due to renal insufficiency.     

Urinary enterolignan concentrations are positively associated with serum HDL cholesterol and negatively associated with serum triglycerides in U.S. adults

Fiber-rich diets are associated with favorable lipid profiles, but the specific compounds and the mechanisms behind this effect are yet to be fully understood. Lignans are fiber-related polyphenols that have been associated with lower prevalence of cardiovascular disease. The objective of this study was to investigate the relationship between dietary lignan exposure, measured as the urinary concentration of their metabolites, enterolactone and enterodiol, and serum lipids in a representative sample of U.S. adults. We carried out a cross-sectional analysis of data from 1492 adults who participated in the 1999-2004 NHANES. The mean urinary concentration of enterolignans in U.S. adults was 1.9 μmol/L. The multivariate-adjusted mean differences comparing the highest and lowest enterolignan tertile were 0.06 mmol/L for HDL cholesterol and -0.17 mmol/L for TG (P < 0.05). In spline regression models, we also found an inverse association between serum TG and urinary enterolignan concentrations. Serum HDL cholesterol levels increased linearly with increasing enterolignan concentrations. Modest or no associations were found between enterolignan concentrations and serum LDL cholesterol or total cholesterol. In conclusion, enterolignan concentrations are associated with lower serum TG concentrations and greater HDL cholesterol concentrations in U.S. adults.     

Modified soybean affects cholesterol metabolism in rats similarly to a commercial cultivar

The consumption of soy protein lowers blood cholesterol in humans and animals. Breeding may alter the physiological effects of soybeans, such as its cholesterol-lowering property. Our hypothesis is that breeding affects the hypocholesterolemic effect of soy by modulating the expression of key hepatic enzymes related to cholesterol and bile acid biosynthesis, as well as altering fecal neutral and acidic steroid excretion. Therefore the aim of this study was to evaluate the effect of a new Brazilian soybean cultivar (UFV-116), lacking lipoxygenases 2 and 3, compared with a commercial cultivar (OCEPAR-19), on 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR) and cholesterol 7α-hydroxylase (CYP7A) mRNA expression and fecal steroid output in rats. Thirty-six male rats were fed UFV-116, OCEPAR-19, or casein as the protein source, with or without addition of dietary cholesterol (0.25%). Blood and liver cholesterol, HMGR and CYP7A mRNA abundance, and fecal excretion of steroids were measured. Blood and liver cholesterol levels were lowered by both soybean cultivars, with and without cholesterol, but UFV-116 was more effective when included in the cholesterol-free diet. Both soy diets promoted lower levels of HMGR mRNA, higher levels of CYP7A mRNA, and higher excretion of fecal secondary bile acids. There was higher fecal neutral steroid output when cholesterol was added to all diets. These data show that both soybean cultivars acted similarly in lowering serum and hepatic cholesterol; therefore, breeding did not affect the hypocholesterolemic effect of the new cultivar.     

Low serum cholesterol concentration and risk of suicide

Recent reports have suggested a link between low serum total cholesterol and risk of death from suicide. We examined this association using participants in the 1970-1972 Nutrition Canada Survey. We determined the mortality experience of Nutrition Canada Survey participants older than 11 years of age at baseline through 1993 by way of record linkage to the Canadian National Mortality Database. The relation between low serum total cholesterol and mortality from suicide was assessed using a stratified analysis (N = 11,554). There were 27 deaths due to suicide. Adjusting for age and sex, we found that those in the lowest quartile of serum total cholesterol concentration (<4.27 mmol/liter) had more than six times the risk of committing suicide (rate ratio = 6.39; 95% confidence interval = 1.27-32.1) as did subjects in the highest quartile (>5.77 mmol/liter). Increased rate ratios of 2.95 and 1.94 were observed for the second and third quartiles, respectively. The effect persisted after the exclusion from the analysis of the first 5 years of follow-up and after the removal of those who were unemployed or who had been treated for depression. These data indicate that low serum total cholesterol level is associated with an increased risk of suicide.     

The Troms? Heart Study: food habits, serum total cholesterol, HDL cholesterol, and triglycerides

Associations between food habits and total serum cholesterol, high density lipoprotein (HDL) cholesterol, and serum triglycerides were examined in 7,410 men and 7,257 women in Troms?, Norway, following a screening in 1979-1980. High body mass index was associated with high serum cholesterol, high triglycerides, and low HDL cholesterol. Positive associations were observed between high serum cholesterol and high coffee consumption, use of butter or hard margarine, not selecting low-fat milk, and low bread consumption. The HDL cholesterol level was virtually independent of the dietary items recorded. Use of low-fat milk and frequent use of fish dishes for dinner seemed to be related to low serum triglyceride levels.     

Television viewing and obesity in adult females.

We measured the relation between time spent watching television per week and obesity in 4,771 adult females. After controlling for age, education, cigarette smoking, length of work week, and weekly duration of exercise, females who reported three to four hours of TV viewing per day showed almost twice the prevalence of obesity (body fat greater than 30 percent), and those who reported more than four hours of TV watching per day showed more than double the prevalence of obesity, compared to the reference group (less than 1 hr/day). Part of the TV/obesity association was a function of differences in exercise duration among the four TV viewing categories.     

大豆蛋白对人体血浆胆固醇的影响及机制探讨

目的观察大豆蛋白对正常人体血浆胆固醇浓度的影响并探讨其作用机制。方法选择健康大学生30名，男女各半，按血浆总胆固醇浓度、体重和性别均衡的原则，分为3组，在统一食谱、集中就餐的基础上，每天分别另外摄入30g酪蛋白，30g大豆分离蛋白，30g酪蛋白加880mg钙，共14d。实验开始和结束时．测量身高和体重：采血，测定血浆总胆固醇浓度。实验结束前，收集3d粪便，测定粪脂肪、钙、磷、镁和胆汁酸的排出量。结果(1)同实验开始时比，酪蛋白组血浆胆固醇浓度显著升高，而大豆蛋白组和酪蛋白加钙组血浆胆固醇浓度升高不明显。(2)同酪蛋白组比，大豆蛋白组粪钙、磷和镁的排出量均显著增加；粪脂肪和胆汁酸排出量分别增加33．6％和45．3％。(3)粪胆汁酸排出量与粪钙、磷、镁和脂肪的排出量呈显著性正相关。血浆胆固醇浓度随粪胆汁酸排出量增加呈下降的趋势。结论大豆蛋白降低血浆胆固醇浓度的机制可能是由于增加粪胆汁酸的排出量而导致肝脏中由胆固醇合成胆汁酸的增加，从而使血浆胆固醇浓度下降。     

Zinc supplements and serum lipids in young adult white males

A 12-wk double-blind study was conducted to determine the effect of oral zinc supplementation upon serum total cholesterol, lipoprotein-cholesterol fractions, and serum triglycerides in white males. The subjects were randomly assigned to one of three treatment groups and consumed either a placebo tablet (n = 9), 50 mg Zn/d (n = 13), or 75 mg Zn/d (n = 9) as Zn gluconate. Serum total cholesterol, low-density-lipoprotein (LDL) cholesterol, very-low-density-lipoprotein (VLDL) cholesterol, and triglycerides were not affected by Zn supplements. However, serum high-density-lipoprotein (HDL)-cholesterol levels in subjects assigned to the 75 mg Zn/d group were significantly lower at weeks 6 and 12 than those for the placebo group and lower at weeks 6, 8, and 12 than at baseline; subjects assigned to the 50 mg Zn/d group had lower serum HDL-cholesterol levels at week 12 than did the placebo group and lower at week 12 than at base line.     

Low serum concentrations of 25-hydroxyvitamin D in young adult Japanese women: a cross sectional study

OBJECTIVES: The vitamin D nutrition status of young adult women is unclear, but a recent preliminary report suggested that they may have vitamin D insufficiency. This study assessed the serum concentrations of 25-hydroxyvitamin D (25[OH]D), an index of vitamin D nutrition status, in young adult Japanese women in comparison with those in older women and investigated whether serum 25(OH)D concentrations are associated with other calcium-related hormones and bone mass. METHODS: A cross sectional study of 77 healthy women, age 19 to 66 y, working in nursing homes in Japan was conducted in the winter of 1999 and 2000. The investigation included blood tests, forearm bone mass measurements, and a lifestyle questionnaire. RESULTS: The mean serum 25(OH)D concentration in women younger than 30 y was 34.0 nmol/L (standard deviation [SD] = 11.0) and significantly lower than that in women 30 y and older (50.0 nmol/L, SD = 14.4). The proportion of subjects younger than 30 y who had serum 25(OH)D concentrations less than 30 nmol/L was 42.1% and was significantly higher (P < 0.001) than the proportion of those 30 y and older (10.3%). There was a weak but significant linear association between serum 25(OH)D concentrations and forearm bone mineral content (R(2) = 0.114, P = 0.0052) but not between serum 25(OH)D concentrations and bone mineral density. The association held after adjusting for body weight (R(2) = 0.139, P = 0.0111). Serum intact parathyroid hormone concentrations were within the normal range and not associated with serum 25(OH)D concentrations. CONCLUSIONS: Serum 25(OH)D concentrations in young adult Japanese women (<30 y old) are lower than those of older adult women (30 to 66 y), and lower serum 25(OH)D concentrations are likely associated with lower forearm bone mineral content.     

Difference in effect of myristic and stearic acid on plasma HDL cholesterol within 24 h in young men

BACKGROUND: There is increasing evidence that postprandial triacylglycerol (TAG)-rich lipoproteins (TRL) may be related to atherogenic risk. Little is known about the acute effect of individual dietary saturated fatty acids on plasma lipids and lipoproteins. OBJECTIVE: To investigate the effect of two prevalent dietary saturated fatty acids, stearic and myristic acid on postprandial and 24 h fasting plasma lipoprotein TAG and cholesterol concentrations. DESIGN: Ten young healthy men were served two meals (1.2 g fat/kg body weight) containing fat enriched in either stearic acid (S) (shea butter) or myristic acid (M) (produced by inter-esterification) in a randomised, cross-over study. The meals were given in the morning after 12 h of fasting and again after 8 h (in the afternoon). The S and M containing meals were given at different days separated by a washout period. Blood samples were taken before the meal and 2,4,6,8, and 24 h after the first meal. RESULTS: The M meal resulted in a higher postprandial HDL TAG response than S (P=0.03 I), (diet x time interaction), while no differences were observed in other lipid fractions. Twenty-four hours after the M meal fasting, HDL cholesterol was higher (P=0.05) and HDL TAG lower (P<0.001) than at baseline. CONCLUSIONS: Intake of individual dietary SFA may affect fasting HDL cholesterol within 24 h. Thus after this short period HDL cholesterol concentration was higher after myristic acid than stearic acid. Myristic acid resulted in a higher increase in postprandial HDL TAG than stearic acid.