自噬在代谢综合征相关的心血管老化中的作用机制

代谢综合征是一组表型复杂的代谢紊乱症候群,发病率居高不下.代谢性综合征病理相关的肥胖、胰岛素抵抗、糖尿病、高血压及脂代谢异常促进心血管过早老化.自噬溶酶体途径可降解心血管老化过程中产生的功能异常的蛋白质和细胞器,参与代谢综合征相关的心血管过早老化的发生发展.为寻找各种代谢性疾病下心血管老化治疗的新策略,掌握代谢应激情况...     

脂肪细胞型脂肪酸结合蛋白与动脉粥样硬化的研究进展

动脉粥样硬化与代谢和炎症反应异常密切相关.脂肪细胞型脂肪酸结合蛋白作为脂肪酸结合蛋白家族中的一员,与动脉粥样硬化、代谢综合征等代谢相关疾病关系密切,成为近来研究的热点.本文就脂肪细胞型脂肪酸结合蛋白的主要特性及其与动脉粥样硬化的关系研究进展作一简要综述.     

血尿酸水平与代谢综合征的相关性

目的探讨血尿酸水平与代谢综合征及其心血管并发症的相关性。方法分析资料完整的1000例代谢综合征患者,按NCEP-ATPⅢ诊断标准,分别探讨与高尿酸血症的关系及高尿酸血症与代谢综合征心血管并发症之间的关系。结果代谢综合征患高尿酸血症者占53%。代谢综合征的5项诊断标准中,以高血压、甘油三酯、腹型肥胖与高尿酸血症的关系最密切。男性高尿酸血症发病率高于女性,年长者高于年青者,合并心血管并发症者高尿酸血症较无心血管并发症者发病率明显增加。结论高尿酸血症与代谢综合征及其心血管并发症密切相关,高尿酸血症可能为代谢综合征的重要组成部分和重要的心血管疾病危险因素。     

代谢综合征与冠状动脉狭窄程度及心血管危险评分的关系

目的 了解代谢综合征患者冠状动脉狭窄程度及心血管危险评分的特点,以探讨代谢综合征与后两者之间的关系.方法 连续收集胸部不适并行冠状动脉CT检查的136例患者,所有患者均检查血压、空腹血糖及血脂,包括甘油三酯、总胆固醇、高密度脂蛋白胆固醇及低密度脂蛋白胆固醇.应用美国2001年NCEP-ATPⅢ代谢综合征诊断标准,将其分为代谢综合征组及非代谢综合征组.冠状动脉狭窄程度用多层螺旋CT测量,比较两组间冠状动脉狭窄程度的差异,并对心血管危险评分中各项指标的差异进行比较.结果 冠状动脉狭窄程度代谢综合征组均较非代谢综合征组为重,两组的高血压、糖尿病患者、血脂异常及心血管危险评分存在明显差异.结论 代谢综合征患者冠状动脉狭窄程度较重,且多数心血管危险评分较高.代谢综合征可作为冠心病的重要危险因素,早期全面干预其中的各个成分有助于冠心病的防治.     

脂肪细胞型脂肪酸结合蛋白与代谢综合征

脂肪细胞型脂肪酸结合蛋白(A-FABP)是近年来新发现的脂肪因子.动物实验表明其可以促进代谢综合征各组分如胰岛素抵抗、血脂紊乱、2型糖尿病和动脉粥样硬化的发生、发展.人群研究也发现,其过度表达而导致血浆中含量增加是反映代谢综合征的一个可靠生物标志物.随着研究的深入,A-FABP对于治疗代谢综合征的作用也日益受到人们的关注.以下主要就近年来有关A-FABP的分布、结构、特性及其与代谢综合征组分的关系作一综述.     

脂肪细胞型脂肪酸结合蛋白研究进展

脂肪细胞型脂肪酸结合蛋白(A-FABP)是脂肪酸结合蛋白家族成员之一,与体重、糖脂代谢及胰岛素敏感性有密切关系,有助于代谢综合征的诊断及危险性预测,可能是代谢综合征一个独立的危险因子.此外,A-FABP还与多囊卵巢综合征以及动脉粥样硬化的发生和进展有关,为代谢性疾病的药物预防和治疗提供了新的潜在靶点.     

血浆磷脂反式脂肪酸与老年人致命性缺血性心脏病和心脏猝死间关系

[英]/Lemaitre RN…//Circulation.-2006,114.-209～215摄入反式脂肪酸与罹患冠心病风险增加有关。然而关于不同类型反式脂肪酸是否与之亦有类似相关关系尚未清楚。作者先前曾报道,红细胞膜表面的反式18:2脂肪酸而不是反式18:1脂肪酸与心脏猝死有关。本文意就不同种类血浆反式脂肪酸与老年人致命性缺血性心脏病和心脏猝死发病间关系进行了评价。对象与方法受试对象为5888例老年人,基线年龄均≥65岁。在1992～1998年随访期间,共有214例罹发致命性缺血性心脏病(包括致命性心肌梗死和因冠心病所致死亡)及心脏猝死,为病例组;另选214例基线临床…     

高血压合并代谢综合征患者血清脂联素与游离脂肪酸谱等代谢参数关系研究

目的 研究原发性高血压合并代谢综合征和未合并代谢综合征患者血清脂联素水平、游离脂肪酸谱特征及与其他糖脂代谢参数间关系.方法 用放射免疫分析法测定128例高血压合并或未合并代谢综合征患者与43例正常对照组血清脂联素,同时用气相色谱/质谱测定其游离脂肪酸成分.结果 高血压合并代谢综合征患者血清脂联素低于未合并代谢综合征组和正常对照组(P＜0.05或P＜0.01),总脂肪酸、不饱和脂肪酸(亚油酸、油酸、花生四烯酸、二十二碳六烯酸、花生三烯酸)、多不饱和脂肪酸(PUFA)和n6PUFA高于未合并代谢综合征组和正常组,差异有统计学意义(P＜0.05或P＜0.01).在研究对象中,脂联素与体重指数、腰围、腰臀比、甘油三酯呈负相关(r=-0.222,-0.235,-0.179,-0.194,P＜0.01或P＜0.05),与高密度脂蛋白胆固醇呈正相关(r=0.336,P＜0.01).总脂肪酸、多不饱和脂肪酸与体重指数、腰围、空腹血糖、平均血压呈正相关(r=0.241和0.280,0.198和0.188,0.226和0.298,0.274和0.334,P＜0.01或P＜0.05).结论 脂联素与游离脂肪酸代谢紊乱、n6系多不饱和脂肪酸升高,可能在原发性高血压合并代谢综合征的发病中起重要作用.     

反式脂肪酸对心血管系统的危害

反式脂肪酸(trans fatty acids,TFA)是一类含有反式双键的非共轭不饱和脂肪酸.越来越多的证据表明TFA对心血管损伤主要由两个方面的效应所致,即脂质效应和非脂质效应[1].     

2型糖尿病合并痛风大血管并发症与细胞因子的关系

细胞因子脂联素（APN）、肿瘤坏死因子-α（TNF-α）、白细胞介素-6（IL-6）与胰岛素抵抗在代谢综合征发病中的作用受到越来越多的关注,它们通过多种机制在2型糖尿病心血管并发症的发生发展中起重要作用。本文就APN、TNF-α、IL-6与2型糖尿病合并痛风心血管并发症的关系综述如下。     

Consensus dietary guidelines for healthy living and prevention of obesity, the metabolic syndrome, diabetes, and related disorders in Asian Indians

India is undergoing rapid nutritional transition, resulting in excess consumption of calories, saturated fats, trans fatty acids, simple sugars, salt and low intake of fiber. Such dietary transition and a sedentary lifestyle have led to an increase in obesity and diet-related non-communicable diseases (type 2 diabetes mellitus [T2DM], cardiovascular disease [CVD], etc.) predominantly in urban, but also in rural areas. In comparison with the previous guidelines, these consensus dietary guidelines include reduction in the intake of carbohydrates, preferential intake of complex carbohydrates and low glycemic index foods, higher intake of fiber, lower intake of saturated fats, optimal ratio of essential fatty acids, reduction in trans fatty acids, slightly higher protein intake, lower intake of salt, and restricted intake of sugar. While these guidelines are applicable to Asian Indians in any geographical setting, they are particularly applicable to those residing in urban and in semi-urban areas. Proper application of these guidelines will help curb the rising "epidemics" of obesity, the metabolic syndrome, hypertension, T2DM, and CVD in Asian Indians.     

Diet and the metabolic syndrome

Lifestyle and diet play important roles in the development of cardiovascular disease (CVD), which is the leading cause of death in Western countries. Metabolic syndrome, which is characterized by a group of metabolic risk factors, is associated with the subsequent development of type 2 diabetes and CVD. Epidemiological studies have documented that nutritional factors may affect the prevalence of the metabolic syndrome. Beyond weight control and reduction of total calories, the diet should be low in saturated fats, trans fats, cholesterol, sodium, and simple sugars. In addition, there should be ample intake of fruits, vegetables, whole grains, and monounsaturated fat; fish intake should be encouraged. These features are very reminiscent of the nutritional principles currently used to define the Mediterranean-style diet. This diet's high fiber content, n-3 fatty acids, and antioxidants, as well as phytochemicals from olive oil, legumes, whole grains, fruits, and vegetables, might be responsible for its beneficial effect on the health of metabolic syndrome patients. This may occur through the reduction of systemic vascular inflammation and endothelium dysfunction without having a drastic effect on body weight. The choice of healthy sources of carbohydrates, fat, and proteins, associated with regular physical activity and avoidance of smoking, is critical to fighting the war against chronic disease.     

Does dietary trans fatty acid intake relate to the prevalence of coronary heart disease in Scotland?

Reports of the effects of trans fatty acids on coronary heartdisease are inconsistent. Trans fatty acids may particularlyinfluence coronary risk when linoleic acid levels are low, asituation which occurs in Scotland where prevalence of coronaryheart disease is also very high. The link between trans fattyacid intake and prevalent coronary heart disease was thereforeinvestigated in the Scottish Heart Health Study population. Trans fatty acid intakes were calculated from 10/359 sets offood-frequency questionnaire data obtained from the cross-sectionalsurvey of men and women aged 40–59 years. Logistic regressionanalysis was used to calculate the odds ratios for prevalentcoronary heart disease by fifths of dietary intake of total,natural and commercial hydrogenation-derived trans fatty acid.The group who had undiagnosed coronary heart disease at thetime of survey was the pertinent group for examining the possiblecausative effects of trans fatty acid intake. After adjustmentfor the confounding factors (i.e. age, weight, height, smoking,level of physical activity, blood pressure, total energy intakeand intakes of saturated fat, linoleic acid and the antioxidantvitamins) the odds of undiagnosed coronary heart disease formen, relative to the lowest intake fifth, did not differ significantlyfrom unity by total or commerciallyderived trans fatty acidintake. Odds were around 35% smaller in the higher intake fifthsof naturally-derived trans fatty acids. For women, the oddsof undiagnosed coronary heart disease tended to be greater inthe higher fifths of total (odds ratio 1·36 (95% confidenceinterval 0·94, 1·89)) and hydrogenated (1·26(0·92,1·72)) trans fatty acid relative to the lowest fifth,but only reached significance in the third fifth of total transfatty acid (1·36 (1·01, 1·83)). Dietary total and commercially-derived trans fatty acids failedto influence the odds of coronary heart disease for men, eventhough a significant increase in the ratio of low density plusvery low density lipoprotein to high density lipoprotein-cholesteroloccurred with trans fatty acid intake. The results, therefore,do not support a major effect of dietary trans fatty acid fromcommercial hydrogenation on coronary heart disease risk in theseScottish men. The results for women are less clear, and thepossibility remains that individuals at the high extreme oftrans fatty acid intake, who may be essential fatty acid deficient,are at enhanced risk of coronary heart disease.     

Postprandial response of trans fatty acids in prepubertal obese children

OBJECTIVES: To evaluate the intake, plasma concentrations and postprandial response of trans fatty acids in obese and control children at prepubertal age in order to detect potential associations with childhood obesity. DESIGN: Case-control study, clinical dietary intervention with a 428 kcal standardized breakfast and longitudinal 3 h postprandial follow-up for trans fatty acid plasma levels. SUBJECTS: Fifty-four children aged 6-13 years of both sexes, 34 obese (body mass index >97th percentile for age and sex) and 20 non-obese (control group) at prepubertal period (Tanner I). MEASUREMENTS: Various anthropometric parameters and sex hormones, fasting insulin and glucose, estimation of dietary trans fatty acid intake and their plasma quantitation in fasting conditions, and for 3 h following intake of a standardized breakfast. RESULTS: Dietary trans fatty acid intake was less than 0.4% of total energy in both groups, with a trend towards higher intake in obese children. Fasting plasma trans fatty acid concentrations and percentages were similar in both groups. However, trans fatty acid levels at +3 h were significantly higher than at 0 h in obese children, but not in controls (obese, 0 h: 2.38+/-0.29; 3 h: 3.62+/-0.45; controls, 0 h: 2.29+/-0.24; 3.14+/-0.49 mg/dl); cis monounsaturated fatty acid concentrations were not significantly affected by the postprandial interval. Obese children exhibited hyperinsulinemia and insulin resistance; however, trans fatty acid intake or their plasma levels were not associated with them. CONCLUSION: There is a low intake of trans fatty acids in Southern Spanish children, which is supported by their low concentrations in plasma. No difference in trans fatty acid intake is observed between obese and control children, although plasma levels remain higher in obese than in control children after 3 h of a meal. A marked insulin resistance is seen in obese, but it is not correlated with either trans fatty acid intake or plasma concentration.     

Lebensstiländerungen zur Prävention koronarer Herzkrankheit

BACKGROUND: In developed countries arteriosclerosis is responsible for the majority of all deaths. With growing prosperity the life expectancy is increasing, and cardiovascular disease is becoming the primary cause of premature death. Most complications of arteriosclerosis occur unexpectedly. Because of the severe morbidity and high mortality prevention is the only true solution. CHANGES OF LIFESTYLE: Unhealthy nutrition, physical inactivity, overweight and smoking have been identified as the primary causes of arteriosclerotic vascular disease. Central obesity is responsible for the risk factors characterizing the metabolic syndrome. This is the result of inappropriate caloric intake and expenditure. In addition, the nutrients themselves can bear harmful consequences either indirectly by deteriorating risk factors like lipid parameters or by affecting directly the vessel wall. This can add to the deleterious effects of smoking. Evidently saturated fat is the single most decisive nutrient for atherosclerotic vascular disease. Cholesterol and trans fatty acids act additive, while unsaturated fatty acids appear to be beneficial. However, total fat intake is an important determinant of the energy supply, which again influences body weight and composite. Physical activity can counteract, but appears to be beneficial by several additional ways. Quitting smoking is highly effective already within few years. Together with physical activity and healthy nutrition more than 80% of all cardiovascular events can be prevented. CONCLUSION: Preventive medicine needs to focus on lifestyle changes because they are feasible and highly effective. A nutrition low in total fat primarily by avoiding saturated and trans fatty acids, but rich in carbohydrates and fiber is recommended. Daily physical activity in any preferred way should be encouraged, and quitting smoking needs to be strongly emphasized.     

Saturated and trans fatty acids and coronary heart disease

Dietary intake of both saturated and trans fatty acids has been associated with an increase in the risk of coronary heart disease (CHD). Evidence comes mainly from controlled dietary experiments with intermediate end points, such as blood lipoproteins, and from observational studies. A few small, randomized controlled trials with clinical end points have been carried out in which saturated fat was replaced with polyunsaturated fat, leading to a reduction in low-density lipoprotein cholesterol and a reduction in CHD risk. However, no such studies exist for trans fatty acids. More high-quality, randomized controlled trials on fatty acids and CHD are required, but public health recommendations to reduce intake of both saturated and trans fatty acids are appropriate based on the current evidence.     

Fatty acid composition of serum lipids: is this marker of fat intake still relevant for identifying metabolic and cardiovascular disorders?

Analysis of the fatty acid composition of serum lipid fractions is an old but still useful method for several purposes. The proportions of essential polyunsaturated and trans fatty acids are biomarkers of dietary intake that can be used to improve estimates of fatty acid intake in dietary trials and population studies. Furthermore, the metabolism of essential n-6 and n-3 fatty acids is reflected in the serum fatty acid composition. Changes in the activity of the delta-6 and delta-5 desaturases, which affect the proportions of dihomogamma-linolenic acid and arachidonic acid in serum lipids, are associated with insulin resistance and may explain differences in coronary heart disease risk.     

Effect of dietary hydrogenated fish oil on the plasma lipoprotein profile and on the fatty acid composition of different tissues on the rat

Dietary fatty acids are actively incorporated into membrane lipids, and fat intake can modify the composition and the biochemical activity of cellular membranes and the pattern of plasma lipoproteins. Industrial hydrogenation of polyunsaturated oils leads to the formation of isomeric trans fatty acids which are incorporated into cellular membranes when they are present in the diet. The trans fatty acid amount present in hydrogenated oils depends on the degree of hydrogenation, being high for partially hydrogenated oils and low for highly hydrogenated oils. Hydrogenated fish oil is widely used in some countries for the production of margarine and industrial fats. This study compares the fatty acid composition of plasma, erythrocytes, subcutaneous adipose tissue, and hepatic microsomal membranes and the plasma lipoprotein profile after feeding rats with a synthetic diet containing either fish oil, partially hydrogenated fish oil, or highly hydrogenated fish oil. It is observed that the tissue content of monounsaturated fatty acids increases and that the content of polyunsaturated fatty acids decreases after an increase of the degree of hydrogenation of the dietary fat. Tissues from animals fed partially hydrogenated fish oil show significant amounts of trans fatty acids only. The plasma triacylglyceride composition and the lipoprotein profile are also altered by the degree of hydrogenation of the dietary fat. Triacylglycerides decrease after highly hydrogenated fat feeding only. Total cholesterol and low-density lipoprotein cholesterol are significantly increased after partially hydrogenated fat feeding. Although no direct evidence is presented, this effect may be attributable to the high content of trans isomers of this dietary fat which nutritionally may behave as saturated fatty acids.     

Dietary factors that promote or retard inflammation

Inflammation plays a pivotal role in all stages of atherosclerosis. Cardiovascular risk factors and metabolic syndrome are typified by low-grade inflammation. Intervention trials convincingly demonstrate that weight loss reduces biomarkers of inflammation, such as C-reactive protein (CRP) and interleukin (IL)-6. Limited studies have shown that certain dietary factors; oleic acid, alpha-linolenic acid, and antioxidants RRR-alpha-alpha tocopherol, reduce biomarkers of inflammation. Most of the studies with fish oil supplementation have shown null effects, and conflicting results have been reported with saturated and trans fatty acids, cholesterol, and soy intake. Much further research is needed to define the role of individual dietary factors on the biomarkers of inflammation and the mechanism of the anti-inflammatory effects of weight loss.     

The scientific basis for trans fatty acid regulations-is it sufficient? A European perspective

The C18:1 trans fatty acids (TFA) comprise a variety of positional isomers, but no definite differences have been documented so far between the metabolic and health effects of industrial and ruminant TFA. In Europe the intake of industrially produced TFA (IP-TFA) has declined, and the majority of TFA are of ruminant origin. TFA have been replaced with cis-unsaturates in soft margarines and they have been reduced also in industrial fats, but often by using palm kernel oils. When modifying the dietary fat composition the proportion of saturated plus TFA should be kept to one-third of total dietary fatty acid intake.