Effect of high fat corn oil, olive oil and fish oil on phospholipid fatty acid composition in male F344 rats

Venous stasis associated with prolonged bed rest can enhance the risk of deep venous thrombosis (DVT). Pneumatic compression of the lower extremities can reduce this risk by preventing venous stasis. When selecting a method of leg compression for their patients, physicians must chose between two distinctly different types of compression devices. One device applies pressure with a single-chambered sleeve to the below knee region while the other applies pressure in a sequential gradient fashion from the ankle to the thigh. The current prospective study was designed to evaluated the ability of two such devices to increase blood flow in the profunda femoral vein. Venous blood flow velocity, compression time, and vein diameter were measured in nine normal experimental subjects using an Accuson duplex-Doppler before, during and after leg compression. Compression with the single-chambered device produced a significant rise in venous blood flow velocity; however, this could not be maintained and our results indicate a higher average velocity was achieved with the sequential gradient device. The sequential gradient device also moved a greater volume of blood and achieved a higher average blood flow rate. The time between deflation of the sleeve and return of a phasic respiratory signal was greater after compression with the sequential gradient device. These results suggest that sequential gradient compression produces the type of hemodynamic alterations needed to reduce the risk of DVT by achieving a sustained increase in venous blood flow and more completely emptying of the veins in the leg.     

Physical activity and plasma lipoprotein lipid concentrations in men

Twenty-three apparently normal untrained men aged 20--55 participated in a 4-month self-regulated training programme ending in a marathon run. Fasting plasma and lipoprotein lipid concentrations, adipose tissue lipoprotein lipase activity, anthropometric data, alcohol consumption, smoking habits, weekly mileage run and performance on a bicycle ergometer were recorded before and after the training period. Training induced an increase in high density lipoprotein cholesterol (HDL-C) concentration which was not directly related to concomitant decreases in mean very low density lipoprotein cholesterol (VLDL-C) concentration or mean total skinfold thickness. The degree of the changes in VLDL lipids and HDL-C levels were related to pretraining values, and changes in HDL-C and VLDL triglycerides (VLDL-TG) were also associated. Initial total skinfold thickness correlated inversely with the change in VLDL-TG levels during training. The pretaining concentration of VLDL-C was related to the corresponding value for HDL-C after training. The magnitude of exercise-induced changes in VLDL-C and HDL-C levels are more related to pre-training levels than to changes in measured exercise parameters, indices of obesity or adipose tissue lipoprotein lipase activity. However, the level of adiposity of subjects at the beginning of the study influenced the response of VLDL-TG levels to increased physical activity. The data suggest that VLDL contributes to the increase in HDL-C levels with exercise but is not the major source of the increment.     

Effect of dietary fish oil supplementation on peroxidation of serum lipids in patients with non-insulin dependent diabetes mellitus

Target 17 of the Health Policy for Europe calls for the health-damaging consumption of dependence-producing substances such as alcohol, tobacco and psychoactive substances to be significantly reduced in all Member States between the year 1980 and the year 2000. With regard to alcohol, it is suggested that alcohol consumption be reduced by 25%, with particular attention to reducing harmful use. A question posed by a number of Member States is what is the level of per capita alcohol consumption of lowest risk to physical, psychological and social harm. A working group was convened to consider population levels of alcohol consumption with particular reference to the Member States of the European Region of WHO. A basis for understanding population problem experience can be established through the interaction between individual risk and distribution of consumption levels within the population. The working group concluded that public health policy within the European Region should continue to advise decreases of per capita consumption. Even when taking into account coronary heart disease, it can be concluded at the population level, across all ranges of alcohol consumption found in almost all countries of Europe, that a reduction in consumption is linked to better health. However, public health policy concerning alcohol should not be based solely on mortality. All outcomes of drinking, that is mortality, morbidity, social and criminal consequences, as well as quality of life, should be considered. The existing data relating alcohol consumption to health originates from countries primarily with a cultural experience of consuming alcohol. In those countries, where there is a cultural or religious tradition of not consuming alcohol, there can be no public health grounds for recommending alcohol consumption.     

Incorporation of n-3 fatty acids into plasma lipid fractions, and erythrocyte membranes and platelets during dietary supplementation with fish, fish oil, and docosahexaenoic acid-rich oil among healthy young men

The effects of n-3 fatty acid supplementation in the form of fresh fish, fish oil, and docosahexaenoic acid (DHA) oil on the fatty acid composition of plasma lipid fractions, and platelets and erythrocyte membranes of young healthy male students were examined. Altogether 59 subjects (aged 19-32 yr, body mass index 16.8-31.3 kg/m2) were randomized into the following diet groups: (i) control group; (ii) fish diet group eating fish meals five times per week [0.38 +/- 0.04 g elcosapentaenoic acid (EPA) and 0.67 +/- 0.09 g DHA per day]; (iii) DHA oil group taking algae-derived DHA oil capsules (1.68 g/d DHA in triglyceride form); and (iv) fish oil group (1.33 g EPA and 0.95 g DHA/d as free fatty acids) for 14 wk. The fatty acid composition of plasma lipids, platelets, and erythrocyte membranes was analyzed by gas chromatography. The subjects kept 4-d food records four times during the study to estimate the intake of nutrients. In the fish diet, in DHA oil, and in fish oil groups, the amounts of n-3 fatty acids increased and those of n-6 fatty acids decreased significantly in plasma lipid fractions and in platelets and erythrocyte membranes. A positive relationship was shown between the total n-3 polyunsaturated fatty acids (PUFA) and EPA and DHA intake and the increase in total n-3 PUFA and EPA and DHA in all lipid fractions analyzed. DHA was preferentially incorporated into phospholipid (PL) and triglyceride (TG) and there was very little uptake in cholesterol ester (CE), while EPA was preferentially incorporated into PL. and CE. The proportion of EPA in plasma lipids and platelets and erythrocyte membranes increased also by DHA supplementation, and the proportion of linoleic acid increased in platelets and erythrocyte membranes in the DHA oil group as well. These results suggest retroconversion of DHA to EPA and that DHA also interferes with linoleic acid metabolism.     

Effect of olive oil on immune function in middle-aged men

Autocrine motility factor is a tumor-secreted cytokine which regulates cellular growth and motility by a receptor-mediated pathway. In the accompanying report (Part I of II), it was demonstrated that high (K1735-M1) and low (K1735-C1.11) metastatic murine melanoma cells display distinct adhesion and spreading characteristics which correlate with their differential spontaneous and stimulated migrations on the extracellular matrix components fibronectin, laminin and collagen IV. These parameters were further related to discrete profiles of focal adhesion plaque integrity and reorganization. Here we describe unique migration patterns observed in these murine melanoma cells which reflect differences in degradation and/or remodeling of the cellular substratum. These profiles of matrix interaction were influenced distinctly by autocrine motility factor and dictated by both substrate composition and cellular phenotype. Since activation of the autocrine motility factor receptor stimulates invasion of a reconstituted basement membrane and enhances experimental metastasis by high- but not low-metastatic K1735 cells, differences in the invasive phenotypes of these cells may be due in part to their differential responses to external stimuli coupled with internal propensities toward either matrix degradation and migration (high-metastatic cells) or matrix remodeling and stasis (low-metastatic cells).     

Effect of two types of fish oil supplementation on plasma and erythrocyte phospholipids in formula-fed term infants

We studied the effect of docosahexaenoic acid (DHA) supplementation of infant formulas on fatty acid composition of blood phospholipids in term infants. Two fish oil supplemented formulas containing 0.45 wt% DHA and high (0.35%) or low (0.10%) eicosapentaenoic acid (EPA) were fed for 42 days and compared with a standard formula and breast milk. Infants fed supplemented formulas and breast milk had similar time-dependent changes for DHA from birth to day 42, i.e., slight decreases in plasma phospholipids and erythrocyte phosphatidylcholine and no change in erythrocyte phosphatidylethanolamine. Low-EPA formula prevented EPA accumulation but did not limit the significant decrease in arachidonic acid (AA) noted in infants fed high-EPA formula. These results suggest that term infant formulas should be supplemented with DHA-rich EPA, low fish oil and AA to achieve a fatty acid status in formula-fed infants similar to that of breast-fed infants.     

Dietary soluble fiber lowers plasma LDL cholesterol concentrations by altering lipoprotein metabolism in female guinea pigs

This experiment was designed to evaluate the effects of pectin (PE), guar gum (GG) and psyllium (PSY) intake on VLDL and LDL metabolism in female guinea pigs fed high dietary cholesterol. Guinea pigs were fed a 15 g/100 g fat diet containing 0.25 g/100 g cholesterol with 12.5 g/100 g PE, 12.5 g/100 g GG, 7.5 g/100 g PSY or 12.5 g/100 g cellulose (control diet) for 4 wk. Plasma cholesterol concentrations were 29, 43 and 39% lower in guinea pigs fed PE, GG or PSY, respectively, compared with the control group (P < 0.0001). Plasma apolipoprotein (apo) B concentrations were 16-22% lower in the groups fed soluble fiber compared with the control group (P < 0.01). In contrast, hepatic cholesterol and triglyceride concentrations were not different among the PE, GG, PSY and control groups. No differences in triacylglycerol (TAG) or apo B secretion rates, measured by blocking VLDL catabolism by triton (WR 1339) injection, were observed, whereas plasma LDL apo B fractional catabolic rates (FCR), determined by injection of radiolabeled LDL, were higher in guinea pigs fed GG or PSY than in those from the control group. All sources of dietary soluble fiber reduced LDL apo B flux (P < 0.05). These results suggest that the mechanisms of plasma LDL cholesterol lowering by dietary soluble fiber are distinctive for each fiber source and result in specific alterations in lipoprotein metabolism in female guinea pigs. Differences between male and female guinea pigs in response to these diets are discussed.     

Lipoprotein lipase transport in plasma: role of muscle and adipose tissues in regulation of plasma lipoprotein lipase concentrations

Lipoprotein lipase (LPL) is synthesized in tissues involved in fatty acid metabolism such as muscle and adipose tissue. LPL is also found in the circulation, but is mostly lipolytically inactive. The proportion of active circulating LPL increases after a fatty meal. We investigated the release of active and inactive LPL from adipose tissue and muscle in the fasting and postprandial states. Arteriovenous concentration gradients of LPL across adipose tissue and forearm muscle were measured in male subjects before and after a fat-rich meal (n = 7) and before and during infusion of a triacylglycerol emulsion (Intralipid) (n = 6). Plasma LPL activity rose after the meal and more so during Intralipid infusion. Plasma LPL mass (>95% inactive LPL) increased after the meal but decreased after Intralipid infusion. In the fasting state (n = 13) muscle efflux of LPL activity was 0.263 +/- 0.098 mU/min per 100 ml of muscle tissue whereas there was an influx of LPL activity to adipose tissue of 0.085 +/- 0.100 mU/min per 100 g of adipose tissue (P < 0. 02 muscle vs. adipose tissue). Similarly in the postprandial state only muscle released LPL activity. Both tissues released LPL mass. In the fasting state efflux was 17.8 +/- 8.8 ng/min per 100 ml muscle and 55.2 +/- 21.3 ng/min per 100 g of adipose tissue (P < 0. 05 muscle vs. adipose tissue). Release of LPL, either active or inactive, was not correlated with levels of non-esterified fatty acids or plasma triacylglycerol. In conclusion, there is a substantial release of LPL from adipose tissue and muscle, most of which is inactive. A small proportion of active LPL seems to be redistributed from muscle to adipose tissue.     

Effects of dietary coconut oil, butter and safflower oil on plasma lipids, lipoproteins and lathosterol levels

BACKGROUND: Complications that develop in groin hernias, such as irreducibility and obstruction, with or without strangulation may make an easily treatable condition a life-threatening one. Identification of risk factors that may predict development would help place the patient in a high-risk group. Priority admission and early elective surgery for such a patient would avoid significant mortality and morbidity. METHODS: This is a 10-year combined prospective and retrospective study of children and adults. Records of complicated groin hernias were identified from July 1985 to July 1995 from the outpatient department and available inpatient medical records. The same number of controls of simple uncomplicated hernias were then chosen using random number tables from among the large number belonging to the same time period. These two groups were then compared and analysed using statistical methods for age, sex, side of hernia, site of hernia (inguinal/femoral), duration of hernia, length of the waiting list for elective surgery, and contents of the hernial sac along with some other parameters to identify patients with high-risk factors. RESULTS: Age was found to be a significant risk factor and predicted complications in both elderly adults and very young children. Sex of the patient (male) and side of hernia (right) were significant risk factors in children only. Site of hernia was an important risk factor and adults with femoral hernia were most likely to experience complications. Duration of hernia for less than a year proved to be the most important risk factor for both children and adults. The majority of patients with complicated hernias had not presented earlier in the outpatient department, which implies that most hernias that become complicated do so within a very short time before patient referral. Mortality was high in patients with coexisting diseases, while morbidity was affected by viability of contents of the hernial sac which in turn was directly affected by duration of irreducibility or delay in presentation. CONCLUSIONS: The risk factors useful in predicting complications in an adult patient with groin hernia were age (older age group), duration of hernia (short duration), type of hernia (femoral more than inguinal) and coexisting medical illness. In children, the risk factors were age (very young), gender (male), short duration of hernia and side (right side).     

Variations in plasma volume affect total and low-density lipoprotein cholesterol concentrations during the menstrual cycle

Serum lipids are known to vary during the menstrual cycle. To determine if changes in plasma volume contribute to this effect, we determined serum lipids, lipoproteins, and estimated changes in plasma volume in 18 premenopausal women at the start of and at 5-day intervals after menstruation. Eleven men served as a comparison group. Changes in plasma volume were estimated from changes in hemoglobin and hematocrit. Total and low-density lipoprotein (LDL) cholesterol (mean +/- SD) increased 15 +/- 14 mg/dL (9% +/- 10%) and 11 +/- 13 (11% +/- 14%) within 10 days after the start of menstruation (P < .05) and then decreased toward baseline during the rest of the cycle. High-density lipoprotein (HDL) cholesterol increased 3 mg/dL, or 5%, (P < .05) on days 10 and 15 after menstruation. Plasma volume decreased 4% +/- 9% (P < .06) 10 days after the start of menstruation, and this maximum decrease in plasma volume coincided with peak increases in total, LDL, and HDL cholesterol. Except for an 8-mg/dL increase in LDL cholesterol at day 5, lipid changes were no longer significant after adjusting for changes in plasma volume. We conclude that alterations in plasma volume account for approximately half of the increase in total and LDL cholesterol during the menstrual cycle.     

Effect of atherogenic diet on chicken plasma lipids and lipoproteins

Adult male White Leghorn chickens were used in an experimental model system to study atherogenesis, and the effects of an atherogenic diet on plasma lipoprotein composition including carotenoids were determined. This model also included treatment with diazepam, a drug known to reduce formation of atherogenic plaques. After 6 wk consumption of a high-cholesterol, high-triglyceride diet, chickens had mean total plasma cholesterol, triglyceride, and carotenoid concentrations that were significantly increased over those from chicks that consumed the standard diet. Diazepam treatment had no significant effect on whole plasma concentrations of these lipids. Total body weight gain was unaffected by diet, but liver weight expressed as percentage of body weight was significantly increased in chickens that consumed the atherogenic diet. High density lipoprotein (HDL) and low density lipoprotein (LDL) fractions were isolated from plasma samples by ultracentrifugation. The atherogenic diet increased the carotenoid, cholesterol, and protein content of the LDL fractions but not the HDL fractions.     

Lipid and lipoprotein concentrations in pregnancies complicated by intrauterine growth restriction

Previous studies have shown that in preeclampsia, plasma lipids climb substantially above levels seen in normal pregnancies. Such lipid changes may play a role in the endothelial damage characteristic of preeclampsia. Pregnancies complicated by intrauterine growth restriction (IUGR), without preeclampsia, have similar placental pathology to preeclampsia despite the absence of the maternal systemic manifestations of hypertension and proteinuria. The aim of this study was to perform a cross-sectional study of lipid and lipoprotein concentrations in the third trimester, from normal pregnancies, and those complicated by IUGR without preeclampsia. Our hypothesis was that, in contrast to the exaggerated lipid changes seen in preeclampsia, lipid and lipoprotein concentrations in IUGR would be similar to those of matched healthy pregnant controls. Fasting blood samples for lipids and lipoprotein fractions were taken in the third trimester, from eight women with IUGR; and eight women with uncomplicated pregnancies, matched as a group for age, booking weight, parity, and gestational age at sampling. There were no significant differences (P > 0.05) in the median concentrations of triglyceride, high-density lipoprotein, and very-low-density lipoprotein 1 (VLDL1), between cases and controls. However, women with IUGR pregnancies had significantly lower cholesterol [4.95 mmol/L (3.35-7.10) vs. 7.47 (5.75-8.45); median (range) for IUGR patients and controls, respectively; P < 0.01], low-density lipoprotein (LDL)-cholesterol [2.45 mmol/L (0.95-3.60) vs. 4.25 (3.35-5.60); P < 0.01], VLDL2 mass [59.0 mg/dL (37-87) vs. 103.0 (64-168); P < 0.01], intermediate-density lipoprotein mass [56.0 mg/dL (31-110) vs. 125.6 (91-157); P < 0.01], and total LDL mass [221.0 mg/dL (104-237) vs. 380.3 (267-534); P < 0.01]. In addition, it was noteworthy that, with respect to LDL-cholesterol and total LDL mass, there was little or no overlap in the ranges of concentrations measured between cases and controls. Because VLDL2 and intermediate-density lipoprotein are the synthetic precursors to LDL in the circulation, their significantly lower median concentrations imply a failure of appropriate LDL synthesis in IUGR pregnancies. Whatever the mechanism, if our results are confirmed in larger studies and longitudinal investigations, then LDL-cholesterol measurements (when LDL-cholesterol fails to rise appropriately or is low in the third trimester) may be of use in identifying mothers with, or at risk of, a pregnancy complicated by IUGR.     

Effect of fish oil on indometacin-induced gastric lesions in rats

The effect of fish oil in promoting the healing of indomethacin-induced gastric lesions was investigated in Wistar albino rats. After indomethacin treatment (30 mg/kg, s.c.), animals were given fish oil, olive oil, or normal diet for 48 h. The ulcer index was found to be decreased to 2.1 +/- 1.8 mm with fish oil, 13.7 +/1 5.4 mm with olive oil, and 14.6 +/- 2.4 mm with normal diet. Fish oil showed a potent healing-promoting effect on acute gastric erosions and ulcers induced by indomethacin and significantly enhanced the mucus content of the mucosa (p < 0.05).     

Diet and plasma lipids in women. I. Macronutrients and plasma total and low-density lipoprotein cholesterol in women: the Framingham nutrition studies

This study examined relationships between diet and plasma total and LDL cholesterol levels in a population-based sample of 695 premenopausal and 727 postmenopausal women participating in the Framingham Offspring/Spouse Study. Regression analyses controlled for age, caloric intake, apolipoprotein E isoform type, estrogen use, and important CVD risk factors indicated that plasma total and LDL-cholesterol levels were directly associated with consumption of saturated fat and inversely associated with total calorie intake. In contrast, dietary cholesterol was not a predictor of plasma total or LDL cholesterol levels. Total cholesterol levels were also directly associated with total fat, oleic acid, and animal fat, and inversely associated with carbohydrate intake. Stepwise regressions with key nutrients indicated that saturated fat was consistently associated with total and LDL cholesterol levels in Framingham women. These analyses suggest that diet explains 2% of the variability in these lipid levels in a cross-sectional sample of women; the full model explains 22-27%.     

Effect of garlic and fish-oil supplementation on serum lipid and lipoprotein concentrations in hypercholesterolemic men

The formation of dehydroluciferin (L) from luciferin (LH2) in the reaction catalyzed by firefly luciferase (EC 1.13.12.7) has been studied. The E.LH2-AMP complex may follow two different pathways: towards production of light and towards the synthesis of the E.L-AMP complex. This last step has an inhibitory effect on light emission as molecules of the enzyme are trapped in a light unproductive complex. The effects of CoA and nucleoside 5'-triphosphates (NTPs) on light emission are quantitatively different. CoA combines with the L moiety of the E.L-AMP complex, yielding L-CoA, promoting liberation of free luciferase, and increasing light yield. NTP reacts with the AMP moiety of the same complex, generating adenosine(5')tetraphospho(5')nucleoside (Ap4N) and, probably, the E. L complex and scarcely increasing light production. The results are discussed in relation to previous reports, by others, on luciferase.     

Compound A: solubility in saline and olive oil; destruction by blood

Compound A is a degradation product of sevoflurane. Knowledge of the solubility of Compound A, CH2F-O-C(=CF2)(CF3), in blood and other solvents would aid in the definition of its kinetics. Accordingly, we determined solvent/gas partition coefficients of Compound A for saline (0.166 +/- 0.002 [mean +/- SD; n = 4]) and olive oil (20.1 +/- 1.1 [n = 4]). Measurement of solubility in blood was confounded by degradation of Compound A in blood and blood components. If a mixture of 99.3% saline and 0.7% oil provides the solubility equivalent to that possessed by blood (as it does for the parent compound, sevoflurane), then blood solubility and solubility in plasma, albumin, red blood cells, or pure hemoglobin is approximately 0.31. The order of Compound A degradation was human plasma = rat blood > whole human blood >5% human serum albumin = washed human red blood cells (hematocrit 50%) = 5% pure hemoglobin. Presuming a solvent/gas partition coefficient of 0.31, respective approximate times for 50% degradation equaled 2.7, 2.8, 4.6, 9.9, 11.0, and 12 min. The accuracy of these approximations was limited by the need to estimate, rather than determine, the solubility of Compound A in such solvents. Pasteurization (heating to 60 degrees C for 12 h) or pretreatment with N-ethylmaleimide (a compound that reversibly binds to sulfhydryl groups) decreased the degradation rate in plasma. These results suggest that degradation arises, at least in part, from reaction of Compound A with proteins in blood, possibly from covalent reaction of Compound A with protein and/or from an enzymatically mediated reaction. The products of degradation, the binding sites, and the clinical implications of such binding and degradation remain to be determined.