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1.
We investigated the lipid metabolism in primary cultured hepatocytes to elucidate the causes of hyperlipidemia, increased cholesteryl esters, and decreased triglyceride levels in the livers of daunomycin-nephrotic rats. The incorporation of 14C-palmitate into phospholipids and triglycerides in primary cultured hepatocytes and medium was similar in daunomycin-nephrotic and control rats. The incorporation of 14C-acetate into phospholipids, triglycerides, cholesterol, cholesteryl esters, and total fatty acids in primary cultured hepatocytes was increased in daunomycin-nephrotic rats. The radioactivity of phospholipids, triglycerides, cholesterol, cholesteryl esters, and very-low-density lipoprotein lipids in medium was increased in the hepatocytes of daunomycin-nephrotic rats using 14C-acetate as a precursor. The increased cholesterogenesis and the increased secretion of triglycerides synthesized from acetate by hepatocytes may be due to an increased cholesteryl ester content and a decreased triglyceride content in the livers of daunomycin-nephrotic rats. The increased secretion of lipids synthesized from acetate by hepatocytes may be due to increased accumulation of lipids in serum and very-low-density lipoprotein in daunomycin-nephrotic rats.  相似文献   

2.
Acute elevation of the coagulant activity of blood coagulation factor VII (FVIIc) is observed after consumption of high-fat meals. This elevation is caused by an increase in the concentration of activated FVII (FVIIa). In a randomized crossover study, we investigated whether saturated, monounsaturated, or polyunsaturated fats differed regarding postprandial activation of FVII. Eighteen healthy young men participated in the study. On 6 separate days each participant consumed two meals (times, 0 and 1 3/4 hours) enriched with 70 g (15 and 55 g) of either rapeseed oil, olive oil, sunflower oil, palm oil, or butter (42% of energy from fat) or isoenergetic low-fat meals (6% of energy from fat). Fasting and series of nonfasting blood samples (the last at time 8 1/2 hours) were collected. Plasma triglycerides, FVIIc, FVIIa, and free fatty acids were analyzed. There were marked effects of the fat quantity on postprandial responses of plasma triglycerides, FVII, and free fatty acids. The high-fat meals caused, in contrast to the low-fat meals, considerable increases in plasma triglycerides. Plasma levels of FVIIc and FVIIa peaks were 7% and 60% higher after consumption of high-fat meals than after consumption of low-fat meals. The five different fat qualities caused similar postprandial increases in plasma triglycerides, FVIIc, and FVIIa. These findings indicate that high-fat meals may be prothrombotic, irrespective of their fatty acid composition. The postprandial FVII activation was not associated with the plasma triglyceride or free fatty acid responses.  相似文献   

3.
To study whether a delayed start of colostrum feeding in calves affects plasma lipids, fatty acids and fat-soluble vitamins, one group was fed colostrum (milkings 1-4) on d 1 and 2, then mature milk up to d 7, whereas two other groups were fed glucose or water on d 1, colostrum (milkings 1-4) on d 2 and 3 and then mature milk up to d 7. In calves fed colostrum on d 1, starting 5-7 h after birth, plasma concentrations of triglycerides, phospholipids, total cholesterol and of essential and nonessential fatty acids in triglyceride, phospholipid and cholesterol ester fractions as well as of carotene, retinol and alpha-tocopherol up to d 7 were significantly higher than in calves in which colostrum feeding started after >24 h of life. On the other hand, plasma concentrations of vitamin B-6, vitamin B-12 and folic acid were not influenced. Results indicated reduced efficiency of absorption of colostral fatty acids and of fat-soluble vitamins, but not of (selected) water-soluble vitamins, if colostrum is not fed on d 1 of life. In conclusion, colostrum intake within the first 24 h of life is required for an adequate plasma lipid, essential fatty acid, carotene, retinol and alpha-tocopherol status in the first week of life of calves.  相似文献   

4.
In the suckling newborn rat, blood ketone bodies begin to increase slowly 4h after birth and then rise sharply between 12 and 16h, whereas the major increase in plasma non-esterified fatty acids and liver carnitine occurs during the first 2h of life, parallel with the onset of suckling. In the starved newborn rat, which shows no increase in liver carnitine unless it is fed with a carnitine solution, the developmental pattern of the ketogenic capacity (tested by feeding a triacylglycerol emulsion, which increases plasma non-esterified fatty acids by 3-fold) is the same as in the suckling animal. This suggests that the increases in plasma non-esterified fatty acids and liver carnitine seen 2h after birth in the suckling animal are not the predominant factors inducing the switch-on of ketogenesis. Injection of butyrate to starved newborn pups resulted in a pattern of blood ketone bodies which was similar to that found after administration of triacylglycerols, but, at all time points studied, the hyperketonaemia was more pronounced with butyrate. It is suggested that, even if the entry of long-chain fatty acids into the mitochondria is a rate-limiting step, it is not the only factor controlling ketogenesis after birth in the rat. As in the adult rat, there is a reciprocal correlation between the liver glycogen content and the concentration of ketone bodies in the blood.  相似文献   

5.
Effects of high-fat and high-protein diets on cold tolerance in fasted rats were investigated. High-fat diets caused significant increases in body weight, blood-free fatty acids (FFA), ketone bodies and glucose, while high-protein diet did not modify any of these parameters. Rats on high-fat diets that were exposed to cold after clipping exhibited an intermediate cold tolerance as assessed by the rate of fall in colonic temperature between control rats on a standard diet and cold-acclimated rats. The extent of increase of blood FFA and decrease of blood glucose due to cold exposure was less in the high-fat diet group than in control group, but greater than in cold-acclimated group. The lower fall in colonic temperature due to cold exposure was signifcantly associated with less increase in blood FFA and less decrease in blood glucose. In this relation the high-fat diet group was also intermediate between the control and cold-acclimated groups. The high-protein diet did not make any difference in cold tolerance and cold-induced changes in blood metabolites as compared with those in control standard diet, although it resulted in a marked increase in urinary nitrogen excretion. These results indicate that a high-fat diet could exert a significant favorable effect on cold tolerance in fasted rats, but the effect would not be as much as as in cold acclimated rats.  相似文献   

6.
Lipids were extracted from the lyophylized free-living planariae P. sibirica according to the procedure of Folch et al. [14] and fractionated by means of thin-layer and column chromatography on the silicagel KSK. Total lipid content of planariae is equal to 28.70% of lyophylized weight, 21.70% of them being presented by phospholipids. Polar lipids include phosphatidylethanolamine, phosphatidylcholine, sphingomyelin, lysophosphatidylcholine and cerebrosides. Neutral lipids are presented by triglycerides, cholesterol cholesterol esters and free fatty acids. Saturated and unsaturated C6--C22 fatty acis were detected in the lipids.  相似文献   

7.
OBJECTIVE: We tested the hypothesis that serum free (nonesterified) fatty acid and triglyceride concentrations are increased in nulliparous women with preeclampsia relative to women with uncomplicated pregnancies and that these lipids decrease post partum, consistent with the known resolution of clinical symptoms. The relationships between serum concentrations of these lipids and the lipid peroxidation metabolite malondialdehyde were also examined. STUDY DESIGN: Predelivery and 24 to 48 hour postpartum venous blood samples were collected from eight women with preeclampsia and nine women with uncomplicated pregnancies after an 8- to 10-hour fast. Sera were analyzed for concentrations of triglycerides, free fatty acids, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and malondialdehyde. RESULTS: Antepartum serum triglyceride and free fatty acid concentrations were increased approximately twofold in women with preeclampsia relative to uncomplicated pregnancies (p <0.02 and 0.004, respectively). Total, high-density lipoprotein, and low-density lipoprotein cholesterol concentrations did not differ between groups. Concentrations of all lipids decreased significantly in both groups within 48 hours post partum. However, triglyceride and free fatty acid concentrations remained higher in women with preeclampsia (p<0.006, both variables). Triglyceride and free fatty acid concentrations correlated positively, both ante partum (R2 0.42, p<0.01) and post partum (R2 0.39, p<0.02). Antepartum concentrations of malondialdehyde were 50% higher in women with preeclampsia (p<0.01) and decreased post partum (p <0.02) but did not decrease in controls (p = 0.07). Antepartum serum triglycerides and free fatty acids correlated positively with malondialdehyde concentrations (R2 0.38, p <0.02, both cases). CONCLUSION: Triglycerides and free fatty acids, but not cholesterol, are increased in preeclampsia and correlate with the lipid peroxidation metabolite malondialdehyde. We speculate that these interactions may contribute to endothelial cell dysfunction in preeclampsia.  相似文献   

8.
The study group consisted of 130 subjects: 50 healthy nonpregnant, 35 healthy women in the I trimester of gestation (gestational age 6-15 weeks) and 45 patients with symptoms of threatened abortion (the same gestational age). In the latter group pain and bleeding ceased after hormonal treatment and spasmolytic drugs. Serum blood concentration of following compounds were determined: total lipids, LDL fraction, total cholesterol, phospholipids, triglycerides, HDL and LDL cholesterol fractions. Threatened abortion had changed lipids profile; diminished concentrations of LDL fraction, total cholesterol, LDL cholesterol fraction and phospholipids were observed. Levels of total lipids, phospholipids and triglycerides++ in blood serum of healthy pregnant women in the I trimester of gestation were higher than in nonpregnant women.  相似文献   

9.
In young rats reared with their mothers, a gradual increase of serum cholesterol, triglycerides, phospholipids and total lipids was found between the 7th and the 18th to 22nd postnatal day. Then the concentrations of lipids gradually decrease. Early weaning at the 18th postnatal day causes a precocious decrease of the concentration of all studied lipids in blood so that their values on days 22 and 26 are significantly lower than in animals weaned on the 30th postnatal day. The body weight of early weaned rats decreases only slightly and returns to normal by the 30th day. The changes in serum lipids after early weaning are caused by differences in the amount of cholesterol and other lipids in breast milk, in comparison with those in the standard laboratory diet. Perhaps they may participate in disturbing the homeostatic equilibrium of cholesterol in early weaned rats.  相似文献   

10.
Plasma beta-hydroxybutyrate concentrations were measured in the offspring of rats that were fed either a control (20% protein) diet or low-protein (8% protein) diet during pregnancy and lactation. Low-protein offspring had significantly lower plasma beta-hydroxybutyrate compared with controls in the fed state (P < .04) and after fasting for 24 hours (P < .001) and 48 hours (P < .04). There were no differences in blood glucose, acetoacetate, plasma glucagon, cholesterol, or glycerol between control and low-protein offspring. However, plasma nonesterified fatty acids (NEFAs) were significantly higher in low-protein offspring in the fed state (P < .05). In contrast, plasma triglycerides and insulin were significantly lower in low-protein offspring compared with controls when fed (P < .001) and after a 24-hour fast (P < .001). These results suggest that poor maternal and early postnatal nutrition can have long-term effects on ketone body metabolism in the offspring during adulthood. This apparent ketosis resistance is similar to that observed in some forms of human diabetes.  相似文献   

11.
Lipids of peripheral blood red cells (total lipids and phospholipids, triglycerides, free fatty acids, cholesterol, cholesterol ethers, lysophospholipids, sphingomyelins, phosphatidylserins, phosphatidylethanolamines, phosphatidylcholines, cardiolipins, phosphatid acids) were assessed in correlation with wave T height on resting ECG. It is shown that iron deficiency anemia patients develop shifts in red blood cell lipid composition contributing to the onset of myocardiodystrophy. The correction of the lipid composition defects is an additional factor decreasing dystrophic processes in the myocardium.  相似文献   

12.
The lipids of highly purified african swine fever virus (ASFV) propagated in porcine bone marrow cells were observed to contain 25.6% phospholipids, 9.7% monoglycerides, 14.1% cholesterol, 17.8% free fatty acids, 14.4% diglycerides, 13.6% triglycerides, and 6.7% cholesterol ethers. Diethyl ether extracts mono-, di-, triglycerides, free fatty acids, 50% of cholesterol and cholesterol ethers, and 25% of phospholipids from the virus. Analysis of the 14C-sodiumacetate incorporation into viral, cellular and plasmatic membrane lipids has shown that (a) different strains of ATV ASFV have identical composition; (b) viral lipid composition is determined by lipid composition of the infected cells plasmatic membrane; (c) the viral lipid composition is influenced by cells used for propagation of the ASFV.  相似文献   

13.
To elucidate the effects of chronic alcohol ingestion in monkeys a synthetic, adequately balanced, fluid diet providing 40% of total calories from ethanol was gavaged through a stomach tube daily over a period of three months. Clinical, biochemical, radioisotope, and histopathological studies were performed at the beginning and end of the experiment. It was observed that chronic alcohol feeding at this dose level caused maked accumulation of triglycerides, cholesterol, and phospholipids in the serum and the liver. In the heart triglycerides and cholesterol ester were increased. Incorporation studies showed increased synthesis of triglycerides in the heart muscle and liver. Histologically the heart showed fatty change of the myocardium and evidence of focal myocytolysis, atrophy of muscle bundles, and early fibrosis. The liver showed generalized fatty change but no cirrhosis.  相似文献   

14.
OBJECTIVE: The triglyceride-lowering effects of omega-3 fats and HDL cholesterol-raising effects of exercise may be appropriate management for dyslipidemia in NIDDM. However, fish oil may impair glycemic control in NIDDM. The present study examined the effects of moderate aerobic exercise and the incorporation of fish into a low-fat (30% total energy) diet on serum lipids and glycemic control in dyslipidemic NIDDM patients. RESEARCH DESIGN AND METHODS: In a controlled, 8-week intervention, 55 sedentary NIDDM subjects with serum triglycerides > 1.8 mmol/l and/or HDL cholesterol < 1.0 mmol/l were randomly assigned to a low-fat diet (30% daily energy intake) with or without one fish meal daily (3.6 g omega-3/day) and further randomized to a moderate (55-65% VO2max) or light (heart rate < 100 bpm) exercise program. An oral glucose tolerance test (75 g), fasting serum glucose, insulin, lipids, and GHb were measured before and after intervention. Self-monitoring of blood glucose was performed throughout. RESULTS: In the 49 subjects who completed the study, moderate exercise improved aerobic fitness (VO2max) by 12% (from 1.87 to 2.07 l/min, P = 0.0001). Fish consumption reduced triglycerides (0.80 mmol/l, P = 0.03) and HDL3 cholesterol (0.05 mmol/l, P = 0.02) and increased HDL2 cholesterol (0.06 mmol/l, P = 0.01). After adjustment for age, sex, and changes in body weight, fish diets were associated with increases in GHb (0.50%, P = 0.05) and self-monitored glucose (0.57 mmol/l, P = 0.0002), which were prevented by moderate exercise. CONCLUSIONS: A reduced fat diet incorporating one daily fish meal reduces serum triglycerides and increases HDL2 cholesterol in dyslipidemic NIDDM patients. Associated deterioration in glycemic control can be prevented by a concomitant program of moderate exercise.  相似文献   

15.
Twelve hyperlipidemic patients on long term treatment with a lipid lowering diet enriched in polyunsaturated fatty acids and with clofibrate were supplemented with vitamin E (400 mg/day). The effect on serum lipoprotein concentration, plasma lipid fatty acid composition, and adipose tissue lipoprotein lipase activity was studied. No additional lipid-lowering effect was registered during a treatment period of 4 months. A slight increase in total serum cholesterol concentration and in high density lipoprotein concentration was probably attributable to seasonal variations in serum lipoprotein concentrations. No major changes of fatty acid composition in plasma cholesteryl esters or triglycerides were recorded. However, an increased relative amount of arachidonic acid and a reduced amount of palmitic acid in the plasma phospholipids after 2 months was possibly caused by the vitamin E therapy.  相似文献   

16.
A prospective study was performed to investigate the effect of short-term lipid infusion on bile composition and its lithogenicity in humans. The study group comprised 44 patients scheduled for laparotomy. The patients were hospitalized 48 h prior to elective surgery and randomized to be infused with a lipid emulsion of either long chain triglycerides (LCT) or a mixture of medium and long chain triglycerides (MCT/LCT) for 6 h of each 24 h, or with glucose-saline. Bile samples were obtained by puncture of the gallbladder during operation. In non-gallstone patients, both lipids caused an elevation of biliary cholesterol and phospholipids, but this effect was more pronounced and significant (P <0.001) only with the mixture of MCT/LCT emulsion. The fatty acid composition of biliary phospholipids was not affected by either lipid infusion. The Cholesterol Saturation Index increased significantly (P <0.005) with the MCT/LCT emulsion and there was insignificant shortening in the nucleation time. In contrast to patients with cholelithiasis, no effects could be demonstrated on gallbladder bile composition, cholesterol saturation index, nucleation time, or fatty acid composition of phospholipids. The effects of both lipid emulsions on plasma lipids and lipoproteins were similar in all groups. Our results indicate that lipid emulsions containing MCT/LCT induce lithogenic changes in the composition of human bile. We propose that the lack of effect of lipid infusion on bile composition in patients with cholelithiasis may be due to precipitation of excess cholesterol in the gallbladder of cholesterol gallstone patients whose bile is already saturated. These findings imply that patients with cholesterol gallstones cannot be grouped with non-gallstone patients in studies of alterations of bile composition.  相似文献   

17.
Previous studies have shown that a diet high in polyunsaturated fatty acids increases mammary tumor incidence in adult and pregnant mice and rats and in the female offspring. The present study investigated whether a high-fat diet alters the number of estrogen receptor (ER) binding sites and protein kinase C (PKC) activity in the mammary gland of these animals. In the female offspring, the effects of maternal exposure to a high-fat diet during pregnancy on development of the mammary epithelial tree were studied also. BALB/c mice were kept on a diet containing either 43% (high-fat) or 16% (low-fat) calories from corn oil, which consists mostly of n-6 polyunsaturated fatty acids, for 1 month. In adult female mice, a 6-fold increase in the number of ER binding sites and 2-fold increase in PKC activity were found in the mammary glands of the high-fat mice when compared with the low-fat mice. In pregnant mice, a high-fat diet increased ER binding sites by 61% and PKC activity by 51%. In contrast to adult and pregnant mice, females exposed to a high-fat diet only in utero through their pregnant mother exhibited a significantly reduced number of mammary ER binding sites by age 45 days (78% decrease) and a reduction in PKC activity by ages 30 and 100 days (44 and 20% decrease, respectively). The mammary epithelial tree of the high-fat offspring contained more terminal end buds and was less differentiated than that of the low-fat offspring. These findings show that consumption of a high-fat diet increases ER and PKC in the adult and pregnant mouse mammary gland, perhaps contributing to the fat-induced promotion of mammary tumorigenesis. In contrast, reduced ER and PKC following a high-fat exposure in utero may be associated with increased susceptibility to carcinogenesis, possibly due to an increased number of terminal end buds that are the sites of neoplastic transformation in the mammary gland.  相似文献   

18.
BACKGROUND: Structured lipids are being incorporated into foods to reduce their energy value. One such lipid is rich in stearic acid. OBJECTIVE: The objective of this study was to compare the effects on plasma lipids of a stearic acid-rich triacylglycerol and a fat rich in palmitic acid in hypercholesterolemic subjects. DESIGN: Fifteen subjects with an average plasma cholesterol concentration of 6.13 +/- 0.80 mmol/L initially ate a low-fat diet for 2 wk (run-in period), followed in random order and blinded fashion by 2 high-fat diets (for 5 wk each) containing foods derived from margarines rich either in palmitic acid or in the structured, stearic acid-rich triacylglycerol. RESULTS: Plasma cholesterol concentrations with the low-fat, the stearic acid-rich, and the palmitic acid-rich diets were not significantly different (5.35 +/- 0.83, 5.41 +/- 0.78, and 5.52 +/- 0.68 mmol/L, respectively) but were significantly lower (P < 0.001) than those measured during the habitual diet period (ie, 2 wk before the study began). Neither HDL cholesterol nor plasma triacylglycerol differed significantly among the 3 study diets. CONCLUSION: A similar increase in the intake of stearic and palmitic acids (differing by approximately 5% of total energy) to ensure a high fat intake resulted in plasma total and LDL-cholesterol concentrations that did not differ significantly from concentrations measured during a period of low-fat intake.  相似文献   

19.
In the rat, both fish oil diet and thyroid hormone replacement are reported to augment bile cholesterol secretion out of proportion to bile flow or secretion of other bile lipids. We sought common mechanisms for these effects and evaluated the role of phospholipid fatty acid composition in the process. Methimazole-treated hypothyroid rats were fed low-fat chow or chow supplemented with 10% corn oil or fish oil, and were studied before and after thyroid hormone treatment. Serum, hepatic, and bile lipids were measured, phospholipid fatty acid composition determined, and hepatic 3-hydroxy-3-methylglutaryl CoA reductase activity assayed. Fish oil diet stimulated cholesterol secretion into bile only after thyroid hormone was given, and this action was synergistic with that of thyroid hormone. Reduced serum cholesterol in fish oil-treated rats was associated with increased biliary cholesterol secretion and diminished hepatic cholesterol content. This suggests that augmented biliary cholesterol secretion may contribute to the fish oil-induced reduction of serum cholesterol. No definite relationship between hepatic or biliary phospholipid fatty acid composition and biliary secretion was apparent, although high bile cholesterol secretion was associated with a low percentage of hepatic and bile phospholipid linoleic acid.  相似文献   

20.
The response of lipids in the blood between two groups of six young women was compared. Group 1 took oral contraceptives and group 2 had never taken oral contraceptives. Two experimental diets supplied about 13% of the calories from protein, 36% from fat, and 51% from carbohydrate. Of the carbohydrate, 84% was either sucrose or wheat starch. Each diet was fed for 4 weeks in a cross-over design. In the portion of the research presented here, subjects were fed a high sucrose meal before each dietary period and after weeks 1 and 3 of each dietary period. Blood lipids were measured before and 30, 60, 120, and 180 min after each meal. Cholesterol and lipoproteins were not affected by the sucrose meal, but free fatty acid levels decreased significantly in both groups. The serum levels of triglycerides, beta-lipoproteins, and cholesterol were significantly higher in users than in nonusers of oral contraceptives. Free fatty acid levels were affected by an interaction between diet and time, and the decrease in response was greater after the sucrose than after the wheat starch diet. Triglycerides, cholesterol, and total lipids were not significantly different after the two carbohydrate diets.  相似文献   

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