Dietary fat and blood lipids

Which oilseed meal provides a higher yield and better nutrient profile of milk in grazing cows?

This study aims to verify which of the oilseed meals will provide a higher milk production efficiency and milk nutrient profile in grazing cows to optimize the production system and improve milk nutrients for the benefit of nutrition and human health. A Latin square experiment was conducted with 12 cows for 84 days, fed Tanzania grass, and concentrated with cottonseed meal (CotM), sunflower meal (SunM), soybean meal (SoyM) and peanut meal (PeaM). SunM tended to have a higher production of 3.5% fat milk and higher milk urea nitrogen compared with the other treatments. SunM tended to have higher amount of fat in the milk compared with SoyM. PeaM tended to have lower fatty acids C13:0, C15:0 anteiso, C15:0 in milk compared with SunM. PeaM tended to have lower C16:0 and C17:0 iso compared with SoyM and CotM. PeaM had lower C18:1trans in comparison to the other meals. The addition of SoyM tended to have higher C18:1 cis15 compared with PeaM and tended to have lower thrombogenicity index compared with CotM and PeaM. Aiming at milk health in pasture production systems, SoyM presented the best nutritional quality of the lipid fraction. For productivity and fat yield, SunM had better results.

Does the use of different oil sources in quail diets impact their productive and reproductive performance, egg quality, and blood constituents?

The present study investigated the impact of dietary oil sources (soybean, corn, peanut, flaxseed, olive, and sunflower oils as sources of omega 3, 6, and 9 fatty acids) on productive and reproductive traits, egg quality, hematological and biochemical blood parameters of laying Japanese quail. A total of 360 eight-week mature Japanese quail were randomly divided into 6 groups fed for 8 wk on a basal diet included with 1.5% of different oil sources. Results showed that the highest egg weights and the best feed conversion ratio (P < 0.01) were recorded for quail fed diets supplemented with 1.5% soybean and peanut oil. The highest hatchability percentages (P < 0.05) were recorded for quail fed diets supplemented with corn oil as compared to the other oils. Furthermore, diets enriched with corn, olive, or sunflower oils had higher values of blood lymphocytes (%) compared to the other treated groups. Blood total cholesterol significantly decreased in quail fed on corn, peanut, flaxseed, or olive oil sources as compared to soybean or sunflower oil groups. Immunologically, the highest levels (P < 0.001) of immunoglobulins (G and M) were recorded for quail fed on corn or olive oil sources compared to other oil sources. Quail consuming olive oil–included diets showed a significant increase in superoxide dismutase and glutathione S-transferase activities and a significant decrease on malondialdehyde level compared with those consumed the other oil sources. It could be concluded that varying the oil source can affect productive, reproductive, and health aspects of Japanese quail. Soybean oil showed good results regarding production aspects; however, olive oil was the best regarding health aspects.

Inclusion of Sunflower Oil in the Bovine Diet Improves Milk Nutritional Profile

Milk and its derivatives are important foods that contribute to daily nutrient requirements and improve consumers' health. This study evaluated the effects of supplementing the diet of lactating dairy cows with sunflower oil (SFO), selenium, and vitamin E on the milk's fatty acid profile and fat oxidative stability as well as the acceptability of the milk by consumers. For this purpose, 32 Jersey dairy cows were allocated to four treatment groups for 60 days, as follows: C (control diet); A (3.5 mg/kg DM (dry matter) organic selenium + 2000 IU vitamin E/cow per day); O (4% SFO DM); OA (equal doses of A and O treatments). The inclusion of SFO decreased the contents of 10:0, 10:1, 11:0, 12:0, 12:1, 14:0, and 9c-14:1 fatty acids as well as odd- and branched-chain fatty acids (13:0, iso 13:0, anteiso 13:0, 15:0, iso 15:0, and 17:0). There was also a tendency for 8:0 and 16:0 fatty acid concentrations to decrease when SFO was included in the cows´ diet. SFO decreased the concentration of 10:0 to 15:0 fatty acids in milk. The sum of the conjugated linoleic acids (CLAs), conjugated alpha-linolenic acid intermediates (CLnAs; 18:3 ω6 + 18:3 ω3), and 22:0 fatty acids in milk tended to increase, and there were significant increases in 18:0 and 9c11t-18:2 with SFO. In terms of the effects of SFO on the health-related lipid indices, the atherogenicity index tended to decrease and h/H tended to increase. When cows were supplemented with antioxidants, the concentration of 20:2 fatty acids decreased, the 6 + 7 + 8 + 9t-18:1, 16t-18:1, 20:0, 22:2, and 24:0 fatty acid concentrations increased, and there was a trend for the 22:1 ω9 fatty acid concentration to increase with antioxidants plus oil. There was a tendency for ω6 fatty acids and ω6/ω3 to increase with milk treated with antioxidants plus oil. The oxidative stability of milk was not influenced by the presence of SFO or antioxidants in the diet of dairy cows. Consumers desired the color and mouthfeel of the milk that was treated with SFO. Cows fed with 4% sunflower oil produced milk with an improved fatty acid profile for human nutrition, containing a higher CLA content and an improved ratio of hypocholesterolemic and hypercholesterolemic fatty acids, without increasing the milk's susceptibility to oxidation. The milk was also rated as being more acceptable by consumers.

Abnormal plasma lipids profile in women with post-adolescent acne

Introduction

Acne vulgaris is a multifactorial chronic inflammatory disease that is increasingly recognized in adult women.

Aim

To investigate a relationship between plasma lipids profile and acne in women and a correlation between selected clinical features of acne (severity, age of onset, location of lesions and the presence of comedones) and lipids profile.

Material and methods

Sixty-four adult women with post-adolescent acne and 20 healthy controls were included in the study. Plasma total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels were determined in all the subjects.

Results

Adult women with acne had statistically significantly increased levels of TC, TG and LDL-C compared to healthy controls (p < 0.05). The level of HDL-C did not differ between the two groups. There was no relationship between higher levels of TC, TG and LDL-C and a clinical picture of acne.

Conclusions

Acne in adult women is likely to be associated with increased levels of TC, TG and LDL-C. This abnormality seems to be important in the pathogenesis of adult acne and could be a result of high fatty acid diet. Performing a lipid profile examination in women with acne should be taken into account when screening patients and followed by appropriate dietary recommendations.

Antiobesity Effects of Sansa (Crataegi fructus) on 3T3-L1 Cells and on High-Fat-High-Cholesterol Diet-Induced Obese Rats

This study was performed to investigate the effects of Crataegi fructus ethanol extracts (CFEEs) on the differentiation of 3T3-L1 cells, and to evaluate the effects of C. fructus powder (CFP) on lipid metabolism and its antiobesity effect in rats fed a high-fat and high-cholesterol (HFC) diet. Both in vitro and in vivo studies were performed for physiological activity and antiobesity effects on the serum, liver, and adipose tissues in obesity-induced rats. CFEEs showed significant inhibitory action on differentiation and triglyceride (TG) accumulation in 3T3-L1 mature cells in a dose-dependent manner. Subcutaneous, mesenteric, epididymal, and total adipose tissue weights of HFC diet group were heavier than those of normal diet (N) group, whereas those of groups fed CFP were significantly decreased. Levels of serum TGs, total cholesterol (TC), and low-density lipoprotein cholesterol were significantly decreased in the CFP groups than in the HFC group, whereas the serum high-density lipoprotein cholesterol level decreased in the HFC group and markedly increased in the CFP groups. TC and TG levels in the liver and adipose tissues were significantly lower in CFP groups than in the HFC groups. In addition, feeding with CFP significantly reduced the occurrence of fatty liver deposits and steatosis, and inhibited an HFC diet-induced increase in adipocyte size. These results suggest that C. fructus may improve lipid metabolism in the serum, liver, and adipose tissue, and may potentially reduce lipid storage.

Nutritious food intake: a new competitive advantage for organizations?

Purpose

The purpose of this paper is to suggest that nutritious food intake is a somewhat overlooked yet essential aspect of corporate wellness that has the potential to help provide organizations with a sustainable competitive advantage.

Design/methodology/approach

The paper first discusses the resource‐based view, identifying ways in which nutritious food intake across an organization may serve to create rare and inimitable organizational resources leading to a competitive advantage. It then presents a basic overview of the fundamentals of nutritious food intake. It proceeds to review the transtheoretical stages of change model in the context of tailored nutrition interventions in organizations, providing a detailed overview of key individual behavior focused and environmental focused change strategies along with a discussion of types of technical delivery systems.

Findings

The paper suggests that an organization may be able to use a tailored stage‐based nutrition intervention as part of a comprehensive wellness program in order to help create a sustainable competitive advantage based on the nutritious food intake of its members.

Research limitations/implications

Future researchers should continue to examine the effectiveness of stage‐based computer tailored nutrition interventions and their delivery systems, particularly in the context of comprehensive corporate wellness plans and the extent to which this serves to create a competitive advantage through lower direct healthcare costs and higher worker productivity.

Practical implications

Organizational leaders should carefully consider the strategies and methodologies presented in this paper when designing and implementing nutrition interventions as part of a broad corporate wellness program.

Originality/value

This paper makes a valuable contribution to the organizational literature by recognizing the potential for the application of the transtheoretical stages of change model from the field of nutrition education within the context of the resource‐based view of organizations.

Role of lipids and fatty acids in macrosomic offspring of diabetic pregnancy

Diabetic pregnancy frequently results in macrosomia or fetal obesity. It seems that the anomalies in carbohydrate and lipid metabolism in macrosomic infants of diabetic mothers are due to maternal hyperglycemia, which leads to fetal hyperinsulinemia. We have developed a rat model of macrosomic offspring and assessed the onset of obesity in these animals. The macrosomic offspring born to diabetic mothers are prone to the development of glucose intolerance and obesity as a function of age. It seems that in utero programming during diabetic pregnancy creates a "metabolic memory" which is responsible for the development of obesity in macrosomic offspring. We have demonstrated that the metabolism of lipids, and altered anti-oxidant status and immune system are implicated in the etiopathology of obesity in these animals. We have reported beneficial effects of n-3 polyunsaturated fatty acids (PUFAs) in obese animals, born to diabetic dams.

Naringin supplementation lowers plasma lipids and enhances erythrocyte antioxidant enzyme activities in hypercholesterolemic subjects

BACKGROUND AND AIMS

Preliminary studies have shown that naringin has a potent lipid-lowering effect and antioxidant capacity in high-cholesterol diet fed animals. Accordingly, the present study was conducted to investigate the effect of naringin on hypercholesterolemic subjects.

METHODS

A hypercholesterolemic group (n=30) and healthy control group (n=30) were established based on the plasma cholesterol levels in the subjects, then all subjects received naringin (400mg/capsule/day) with regular meals for a period of 8 weeks.

RESULTS

In the hypercholesterolemic subjects, naringin supplementation was found to lower the plasma total cholesterol by 14% and low-density lipoprotein cholesterol concentrations by 17%, while the plasma triglyceride and high-density lipoprotein cholesterol concentrations remained unaffected. The apolipoprotein B levels in the hypercholesterolemic subjects were significantly lowered after naringin treatment, yet no change was observed in the apolipoprotein A-1 levels. The erythrocyte superoxide dismutase and catalase activities in the hypercholesterolemic group were significantly increased, whereas the glutathione peroxidase activity and plasma TBARS levels were not different from the baseline measurements. Meanwhile, naringin supplementation had no affect on plasma lipids, apolipoproteins, and TBARS levels or antioxidant enzyme activities in the control group.

CONCLUSIONS

Therefore, these data suggest that naringin may play an important role in lowering plasma cholesterol and regulating the antioxidant capacity in hypercholesterolemic subjects.

Taurine prevents hypercholesterolemia in ovariectomized rats fed corn oil but not in those fed coconut oil

We studied whether the type of dietary fatty acid influences the preventive effect of taurine on the ovarian hormone deficiency-induced increase in plasma cholesterol concentration in 6-mo-old ovariectomized rats. Rats were fed one of the following four diets for 28 d: purified diets based on corn oil, which is rich in linoleic acid, with or with out taurine (50 g/kg) or purified diets based on coconut oil, which is rich in lauric and myristic acids, with or without taurine. Body mass gain, food intake, liver weight and plasma apolipoprotein (apo) A-I, apo B, LDL and VLDL concentrations were not affected by the diets. On the other hand, taurine lowered the plasma total cholesterol concentration (P < 0.02) in rats fed corn oil, but not in those fed coconut oil. In rats fed both types of oils, taurine increased the LDL receptor mRNA level (P < 0.01), hepatic cholesterol 7alpha-hydroxylase activity (P < 0.01) and fecal bile acid excretion (P < 0.01). Taurine increased the HMG-CoA reductase mRNA level (P < 0.02) in the liver of rats fed coconut oil, but not in those fed corn oil. Taurine increased liver total lipid (P < 0.05) and triglyceride (P < 0.05) concentrations in rats fed corn oil, but not in those fed coconut oil. These results indicate that the effect of taurine on ovarian hormone deficiency-induced changes in cholesterol metabolism is influenced by the type of dietary fatty acids.

[Hypocholesterolemia in hospitalized elderly: relations with inflammatory and nutritional status]

PURPOSE

Hypocholesterolemia is a common finding in hospitalized elderly people and is associated with increased mortality. Changes in plasma lipid levels are well known in the acute phase response. It has also been suggested that malnutrition is a cause of hypocholesterolemia. However, malnutrition is the reflect of general condition, and the respective roles of malnutrition and inflammation have not yet been clearly established. This research project was undertaken to examine the impact of nutritional and inflammatory status on the hypocholesterolemia.

METHODS

In a prospective study, 597 elderly patients (83 +/- 7 years) consecutively admitted in a geriatric acute care unit were included. Clinical and anthropometric data: Body Mass Index (BMI), Tricipital Skinfold Thickness (TSF), Sub-Scapular Skinfold Thickness (SSF), Mid Arm Circumference (MAC) have been collected. The blood samples were obtained within the 72 hours following the admission. Nutritional proteins (albumin, prealbumin, transferrin, retinol binding protein); inflammatory proteins (CRP, alpha-1 acid glycoprotein), and blood lipids (cholesterol, LDL, HDL cholesterol, triglycerides, apoproteins A1 and B) were dosed.

RESULTS

The anthropometric and biologic parameters have been compared on the two sexes, significant differences were observed only for blood lipids. The analyses are thus realized and presented by sex separately. Four groups of patients are generated according to the quartile of total cholesterol. Means and standard deviation for all factors are calculated within each group. Both, the trend of means and analyses of correlation show associations with cholesterol in the two sexes. The analysis of variance showed that the cholesterolemia is associated with 1/ decrease in the values of the anthropometrics, and nutritional proteins and 2/ upward trends of the inflammatory parameters. Significant correlations were observed for all transport proteins and CRP with total cholesterol in men and women. The multiple linear regression of the total cholesterol retained albumin, APO A1, APO B and RBP as predictor factors of cholesterolemia for women and APO A1, APO B and tryglicerid for men. When patients with infectious diseases were compared to the others, significant differences have been observed for total cholesterol and all blood lipids, as well as for nutritional and inflammatory proteins.

CONCLUSION

The results confirm an association between nutritional status and hypocholesterolemia, and suggest also the responsability of inflammation as a cause of hypocholesterolemia.

Effects of oleic-rich and omega-3-rich diets on serum lipid pattern and lipid oxidation in mildly hypercholesterolemic patients

AIMS

To evaluate which dietary fat elicits the best response in terms of plasma lipids, lipoproteins, and oxidative processes.

METHODS

After a 4-week run-in period, 14 mildly hypercholesterolemic subjects were fed two balanced diets for 6-week periods. During the first intervention period, patients received a monounsaturated fatty acid (MUFA)-enriched diet (olive oil diet). During the second period this diet was supplemented by n-3 polyunsaturated fatty acids (PUFAs) (n-3 diet).

RESULTS

After the olive oil diet, a significant decrease in total serum cholesterol (-8.54%, P<0.01), and in apolipoprotein B (Apo B) (-10.0%, P<0.01) was observed. With the addition of n-3 fatty acids no further significant changes in serum lipid concentrations were found. However, the n-3 diet was followed by an increase in lipoperoxides in isolated native low-density lipoprotein (LDL) (67.23%, P<0.01).

CONCLUSIONS

A beneficial effect on the serum lipid pattern was observed with the olive oil-enriched diet. The lack of further beneficial modifications on blood lipids and lipoproteins and the increase in the oxidative susceptibility of LDL observed after the addition of n-3 PUFA to the olive oil diet does not favor the use of this diet in hypercholesterolemic patients if it is not associated with a high intake of antioxidants.

Influence of source and percentage of fat added to diet on performance and fatty acid composition of egg yolks of two strains of laying hens

We conducted a trial to study the influence of strain of hen (white vs. brown) and source and percentage of added fat to diet on productive performance and fatty acid (FA) profile of the egg yolk. There were nine dietary treatments: a control diet without added fat and eight diets arranged as a 2 x 4 factorial (5 vs. 10% added tallow, olive, soy, or linseed oil). Each treatment was replicated five times, and the trial lasted 12 wk. White hens produced yolks with more saturated FA (P < 0.001) and less monounsaturated FA (P < 0.001) and polyunsaturated FA (P < 0.05) than brown hens. Fat supplementation improved egg mass output (P < 0.05) and feed efficiency of hens (P < 0.001). Linseed and soy oil diets produced greater egg mass than diets based on tallow or olive oil (59.6, 59.4, 57.9, and 57.1%, respectively; P < 0.001). The proportion of saturated FA in the yolk decreased as the percentage of added fat increased (36.5, 32.3, and 31.0% for diets containing 0, 5, and 10% added fat, respectively; P < 0.001). When the alpha-linolenic acid content of the diets increased from 0 to 0.8%, the arachidonic, docosapentanoic, and docosahexanoic acids in the egg yolk increased. Increases in the alpha-linolenic acid content of the diet over 2.3% did not further augment the concentration of docosapentanoic or docosahexanoic acid of the yolk and, in fact, decreased that of arachidonic acid. Only diets supplemented with linseed oil produced eggs with measurable amounts of eicosapentanoic acid. Diets supplemented with soy oil, with moderate levels of alpha-linolenic acid and high levels of linoleic acid, increased arachidonic and docosahexanoic acids in the egg yolk but not eicosapentanoic acid.

Stearic acid modifies very low density lipoprotein lipid composition and particle size differently from shorter-chain saturated fatty acids in cultured rat hepatocytes

Stearic acid as compared to myristate, palmitate, or oleate is poorly incorporated into triacylglycerol, a major lipid component of very low density lipoprotein (VLDL). The present study investigated the effects of these fatty acids on VLDL metabolism in cultured rat hepatocytes. All fatty acids stimulated [2-3H] glycerol incorporation into VLDL lipids and secretion of [3H]-labeled VLDL by hepatocytes. However, the rate of [3H]-labeled VLDL secretion in the presence of nonlabeled stearate (12.8 +/- 0.7 pmol/mg protein/4 h) was 46, 59, and 22% of that observed for those treated with myristate, palmitate, and oleate, respectively. [1-14C]Stearate as a substrate was also less effective than other labeled fatty acids to be incorporated into VLDL lipids. Of total VLDL lipids synthesized from [1-14C] stearate, triacylglycerol accounted for 78% as compared to 88-97% of that derived from palmitate, myristate, and oleate. The amounts of apoB100 and apoB48 were the same in hepatocytes treated with or without exogenous fatty acids. Similarly, the rate of apoB synthesis from [35S] methionine was not affected by exogenous fatty acids. The treatment of cells with various saturated fatty acids increased the particle size of VLDL to different extents. The largest particles of VLDL, with a mean diameter of 79.3 +/- 11.9 nm, were seen in the cells treated with stearate, followed by those treated with palmitate and myristate (45.5 +/- 9.8 and 38.6 +/- 6.8 nm, diameter, respectively). Clearly, hepatocytes treated with stearate secrete less VLDL and produce larger VLDL particles than those treated with shorter-chain saturated fatty acids.

Continuous infusion of adrenocorticotropin elevates circulating lipoprotein cholesterol and corticosterone concentrations in chickens

The purpose of the present study was to investigate the effects of elevated corticosterone (CORT) on circulating lipoprotein cholesterol during a 1-wk period. For this study, 15 commercial broilers were randomly assigned to one of three treatment groups. Group 1 served as the control (CON) and received no treatment, whereas Groups 2 and 3 received subcutaneous mini-osmotic pumps containing either physiological saline (PS) or adrenocorticotropin (ACTH), respectively. The ACTH was delivered at a rate of 8 IU/kg of BW/d. Blood samples were taken at Time 0 (before implants) and on Days 2, 4, and 7 postimplantation. Continuous infusion of ACTH increased plasma glucose, cholesterol, triglycerides, very low density lipoprotein cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and CORT during the postimplantation period. The group treated with ACTH also exhibited a decrease in BW during the last 2 sampling d. There were no differences in any of the serum constituents measured between CON and PS birds, which suggest that CON birds can serve as useful controls. These data suggest that birds given a continuous infusion of ACTH at 8 IU/kg of BW/d can experience changes in plasma lipoprotein cholesterol concentrations along with changes in other blood parameters and may serve as a useful model in accelerated lipoprotein production.

Ten-year changes in the obesity, abdominal adiposity, and serum lipoprotein cholesterol measures of Western Samoan men

Previously reported associations between abdominal adiposity and coronary heart disease (CHD) may be mediated through serum lipids. In the present longitudinal study, 43 Western Samoan men who participated in a 1982 study were recontacted for a second determination of anthropometric and serum lipoprotein cholesterol levels. The men showed dramatic increases in weight (mean change +/- SD: 10.5 +/- 8.8 kg), abdominal circumference (10.0 +/- 7.6 cm), total cholesterol (49.5 +/- 26.4 mg/dl), and non-HDL cholesterol (53.1 +/- 26.6 mg/dl). A new indicator was used to estimate changes in abdominal adiposity: the residual from the regression of change in the abdominal circumference on change in body weight (the AR). The AR was significantly correlated with changes in total (r = 0.38) and non-HDL cholesterol (r = 0.39). Changes in HDL cholesterol were correlated with changes in weight only (r = -0.37). These bivariate relations remained significant in multiple linear regression analyses. These longitudinal results are the first to suggest changes in abdominal adiposity are related to changes in total and non-HDL cholesterol levels.

Enthusiasm misplaced? Revisiting cholesterol screening

Nursing journals have not reflected the abundant literature criticizing the National Cholesterol Education Program's goal to screen every adult American's cholesterol levels. Because this goal affects every nurse in professional, economic, and personal ways, it behooves nurses to consider the intensive debate that frames the benefits claimed for cholesterol screening. Issues raised by the debate may give nurses reason to question the program's goals. Once acquainted with inherent epidemiologic, methodologic, cost, and public policy issues, nurses may conclude there is insufficient scientific evidence to warrant cholesterol screening for the entire adult population. Rather, cholesterol screening may best be reserved for the relatively few Americans most likely to benefit from both screening and subsequent treatment.

The questionable wisdom of a low-fat diet and cholesterol reduction

The prevalent wisdom that a low-fat diet and cholesterol reduction are essential to good cardiovascular health is coming under increased scrutiny. An examination of the foundations of this view suggests that in many respects it was ill-conceived from the outset and, with the accumulation of new evidence, it is becoming progressively less tenable. Cross-sectional, longitudinal and cross-cultural investigations have variously suggested that the relationship between dietary fat intake and death from heart disease is positive, negative and random. These data are incompatible with the view that dietary fat intake has any causal role in cardiovascular health. Although hypercholesterolemia is associated with increased liability to death from heart disease, it is as frequently associated with increased overall life expectancy as with decreased life expectancy. These findings are incompatible with labelling hypercholesterolemia an overall health hazard. Moreover, it is questionable if the cardiovascular liability associated with hypercholesterolemia is either causal or reversible. The complex relationships between diet, serum cholesterol, atherosclerosis and mortality and their interactions with genetic and environmental factors suggest that the effects of simple dietary prescriptions are unlikely to be predictable, let alone beneficial. These cautions are borne out by numerous studies which have shown that multifactorial primary intervention to lower cholesterol levels is as likely to increase death from cardiovascular causes as to decrease it. Importantly, the only significant overall effect of cholesterol-lowering intervention that has ever been shown is increased mortality. The stress and helplessness associated with misapprehensions as to the dangers of dietary fat and the asceticism inherent in the war on cholesterol have considerable implications for health practices. Recent research in behavioral immunology suggests that stress and helplessness are likely to compromise immunity and promote ill-health.

Cardiovascular risk determination: discrepancy between total cholesterol evaluation and two compound laboratory indices in Norway

OBJECTIVE

To compare group classification of cardiovascular risk by two compound laboratory indices with classification according to the serum total cholesterol concentration alone.

DESIGN

Healthy employees were defined as low and high cardiovascular risk subjects according to their total cholesterol concentration or two compound indices of blood lipid components-the total cholesterol: high density lipoprotein (HDL) cholesterol ratio and an atherogenic index defined as ([total cholesterol-HDL cholesterol]*[apolipoprotein B])/([HDL cholesterol]*[apolipoprotein A-I]). Cut off values to distinguish between low and high risk subjects were as follows: total cholesterol 6.5 mmol/l, HDL cholesterol 0.9 mmol/l, apolipoprotein A = 1.8 g/l, and apolipoprotein B = 1.3 g/l. These gave total: HDL cholesterol ratio and atherogenic index cut off values of 7.2 and 4.5 respectively.

SETTING

An occupational health service in a non-manufacturing company in Norway.

PARTICIPANTS

A total of 112 male and 117 female employees. The mean body mass index values were 25.6 and 23.6 kg/m2 and the mean ages 39.8 and 40.1 years in men and women respectively. Those with cardiovascular, diabetic, or renal diseases were excluded.

MEAN OUTCOME MEASURES

Serum total cholesterol, HDL cholesterol, apolipoproteins A-I and B, lipid peroxidation, blood pressure, smoking, physical activity, and fruit, vegetables, and salt in the diet were determined.

RESULTS

The cut off values allocated 19%, 7%, and 40% as high risk subjects according to total cholesterol, total: HDL cholesterol, and the atherogenic index respectively. The mean age was two to four years higher in the high risk groups. Cardiovascular risk in siblings and no reported physical activity were more prevalent in those high risk groups defined by the compound indices than by total cholesterol alone, as was a high body mass index and a measure of lipid peroxidation. Grouping according to total cholesterol failed to allocate heavy smokers mainly to the high risk group. Diet variables did not demarcate clearly between indices.

CONCLUSIONS

There is considerable variability in classification into high and low risk subjects when using the total cholesterol concentration alone compared with compound risk indices. Smoking was more prevalent in the high risk groups defined by the compound indices than by total cholesterol. These findings call for caution when total cholesterol is used to estimate cardiovascular risk in epidemiological studies, and even more so at individual counselling in occupational or primary health care settings.

Influence of nutrients and cytokines on endothelial cell metabolism

The vascular endothelium plays an active role in physiological processes such as hemostasis, regulation of vessel tone and vascular permeability. Cell injury, or any event which disrupts endothelial integrity and thus endothelial permeability properties, may be involved in the early events leading to atherosclerotic lesion formation. Because of its constant exposure to blood components, including prooxidants, diet-derived fats and their derivatives, the endothelium is susceptible to oxidative stress and to injury mediated by blood lipid components. It is likely that these events potentiate the overall inflammatory response to injury by increasing cytokine release in proximity to the endothelium, which then could further disrupt endothelial barrier function. Even though mechanisms associated with lipid/cytokine-mediated endothelial cell dysfunction are unclear, our data suggest that they may be both oxidative and non-oxidative in nature. We suggest that dietary fats, rich in certain unsaturated fatty acids are atherogenic by enhancing the formation of reactive oxygen intermediates. These intermediates can activate oxidative stress-responsive transcription factors, such as NF-kappa B, which in turn may promote cytokine production, adhesion molecule expression and ultimately endothelial barrier dysfunction. The resulting disturbances in endothelial integrity possibly allow increased penetration of cholesterol-rich lipoprotein remnants into the arterial wall, a critical event in the etiology of atherosclerosis. Data suggest that certain nutrients, which have antioxidant and/or membrane stabilizing properties, protect endothelial cells by interfering with the above proposed mechanisms of endothelial cell dysfunction.

Lipoprotein, lecithin:cholesterol acyl transferase and acetyl CoA carboxylase in stroke-prone spontaneously hypertensive rats fed a diet high in eicosapentaenoic acid

To investigate the effect of dietary eicosapentaenoic acid (EPA) on plasma lipoprotein levels, lecithin:cholesterol acyltransferase (LCAT) activity and liver acetyl CoA carboxylase activity, highly concentrated EPA (78%) purified from sardine oil was fed to stroke-prone spontaneously hypertensive rats (SHRSP) for 30 days. Significantly (P < 0.05) lower systolic blood pressure and plasma total cholesterol were observed in rats fed an EPA diet. In addition, higher HDL cholesterol and lower VLDL cholesterol levels were found in rats fed the EPA diet as compared with rats fed the control diet. However, no significant change of plasma LDL cholesterol was observed in rats between the two dietary groups. EPA supplementation increased the activity of plasma LCAT in rats. In addition, rats fed an EPA diet had lower liver total lipids and adipose tissue weights. However, higher liver acetyl CoA carboxylase activity was observed in rats fed the EPA diet. Results from the present study suggest that dietary EPA might stimulate the plasma lipoprotein metabolism and also alter lipogenesis in the liver of SHRSP rats.