About Entrez
Text Version
Entrez PubMed
Overview
Help |
FAQ
Tutorials
New/Noteworthy 
E-Utilities
PubMed Services
Journals Database
MeSH Database
Single Citation Matcher
Batch Citation Matcher
Clinical Queries
Special Queries
LinkOut
My NCBI
Related Resources
Order Documents
NLM Mobile
NLM Catalog
NLM Gateway
TOXNET
Consumer Health
Clinical Alerts
ClinicalTrials.gov
PubMed Central
|
|
| Display Show |
 |
|
|
Dietary fatty acids early in life affect lipid metabolism and adiposity in young rats.
Silva AP, Guimaraes DE, Mizurini DM, Maia IC, Ortiz-Costa S, Sardinha FL, do Carmo MG.
Instituto de Nutricao Josue de Castro, Centro de Ciencias da Saude, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
The purpose of this study was to evaluate the effects of four isoenergetic diets of differing fat composition on blood lipid profile and adiposity in young rats. Diets containing different lipid sources--partially hydrogenated vegetable oil (PHVO), palm oil (PO), canola oil (CO), and soy oil (SO)--were fed to lactating rats during the 21 days of lactation, and then fed to young males following weaning until the 45th day of life. In vivo lipogenesis rate (LR), lipid content (LC), relative level of FA, and the activity of lipoprotein lipase (LPL) enzyme were measured in epididymal adipose tissue (EPI). Fasting blood lipoproteins and LC in the carcass were also appraised. Body weight of PO and PHVO groups was significantly higher than CO and SO groups from day 14 of lactation to day 45, despite the lower food intake in the PHVO group. PO and PHVO groups presented higher LR and LC in EPI than SO and CO groups. Carcass fat content was significantly higher in PHVO and PO groups than in CO and SO groups. The LPL activity in EPI was unaffected by dietary lipids. PHVO group had increased total cholesterol and TAG concentrations in comparison with the PO group, and significantly lower HDL level compared with the other groups. These results show that the kind of FA in the dietary lipid offered early in life can affect lipid metabolism and adiposity.
PMID: 16981431 [PubMed - indexed for MEDLINE]
Dose-response impact of various tocotrienols on serum lipid parameters in 5-week-old female chickens.
Yu SG, Thomas AM, Gapor A, Tan B, Qureshi N, Qureshi AA.
Advanced Medical Research, Madison, Wisconsin 53719, USA.
The cholesterol-suppressive action of the tocotrienol-rich-fraction (TRF) of palm oil may be due to the effect of its constituent tocotrienols on beta-hydroxy-beta-methylglutaryl coenzyme A (HMG-CoA) reductase activity. The tocotrienols, modulate HMG-CoA reductase activity via a post-transcriptional mechanism. As a consequence small doses (5-200 ppm) of TRF-supplemented diets fed to experimental animals lower serum cholesterol levels. These findings led us to evaluate the safety and efficacy of large supplements of TRF and its constituents. Diets supplemented with 50, 100, 250, 500, 1000, or 2000 ppm of TRF, alpha-tocopherol, alpha-tocotrienol, gamma-tocotrienol, or 6-tocotrienol were fed to chickens for 4 wk. There were no differences between groups or within groups in weight gain, or in feed consumption at the termination of the feeding period. Supplemental TRF produced a dose-response (50-2000 ppm) lowering of serum total and LDL cholesterol levels of 22% and 52% (P < 0.05), respectively, compared with the control group. alpha-Tocopherol did not affect total or LDL-cholesterol levels. Supplemental alpha-tocotrienol within the 50-500 ppm range produced a dose-response lowering of total (17%) and LDL (33%) cholesterol levels. The more potent gamma and delta isomers yielded dose-response (50-2,000 ppm) reductions of serum total (32%) and LDL (66%) cholesterol levels. HDL cholesterol levels were minimally impacted by the tocotrienols; as a result, the HDL/LDL cholesterol ratios were markedly improved (123-150%) by the supplements. Serum triglyceride levels were significantly lower in sera of pullets receiving the higher supplements. The safe dose of various tocotrienols for human consumption might be 200-1000 mg/d based on this study.
PMID: 16933790 [PubMed - indexed for MEDLINE]
Palm and partially hydrogenated soybean oils adversely alter lipoprotein profiles compared with soybean and canola oils in moderately hyperlipidemic subjects.
Vega-Lopez S, Ausman LM, Jalbert SM, Erkkila AT, Lichtenstein AH.
Cardiovascular Nutrition Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA.
BACKGROUND: Partially hydrogenated fat has an unfavorable effect on cardiovascular disease risk. Palm oil is a potential substitute because of favorable physical characteristics. OBJECTIVE: We assessed the effect of palm oil on lipoprotein profiles compared with the effects of both partially hydrogenated fat and oils high in monounsaturated or polyunsaturated fatty acids. DESIGN: Fifteen volunteers aged > or =50 y with LDL cholesterol > or =130 mg/dL were provided with food for each of 4 diets (35 d/phase) varying in type of fat (partially hydrogenated soybean, soybean, palm, or canola; two-thirds fat, 20% of energy). Plasma fatty acid profiles, lipids, lipoproteins, apolipoprotein A-I, apolipoprotein B, lipoprotein(a), glucose, insulin, HDL subfractions, and indicators of lipoprotein metabolism (HDL-cholesterol fractional esterification rate, cholesteryl ester transfer protein, phospholipid transfer protein, and paraoxonase activities) were measured at the end of each phase. RESULTS: Plasma fatty acid profiles reflected the main source of dietary fat. Partially hydrogenated soybean and palm oils resulted in higher LDL-cholesterol concentrations than did soybean (12% and 14%, respectively; P < 0.05) and canola (16% and 18%; P < 0.05) oils. Apolipoprotein B (P < 0.05) and A-I (P < 0.05) concentrations mirrored the pattern of LDL- and HDL-cholesterol concentrations, respectively. No significant effect on the total-to-HDL cholesterol ratio was observed for palm oil compared with the other dietary fats. HDL3 cholesterol was higher after palm oil than after partially hydrogenated and soybean oils (P < 0.05). Differences in measures of glucose and HDL intravascular processing attributable to dietary fat were small. CONCLUSION: Palm and partially hydrogenated soybean oils, compared with soybean and canola oils, adversely altered the lipoprotein profile in moderately hyperlipidemic subjects without significantly affecting HDL intravascular processing markers.
Publication Types:
PMID: 16825681 [PubMed - indexed for MEDLINE]
Dietary patterns and risk of nonfatal acute myocardial infarction in Costa Rican adults.
Martinez-Ortiz JA, Fung TT, Baylin A, Hu FB, Campos H.
Escuela de Nutricion Humana, Universidad de Costa Rica, San Pedro de Montes de Oca, Costa Rica.
OBJECTIVE: To investigate the association between dietary patterns and risk of a first nonfatal acute myocardial infarction (MI) in Costa Rican adults. DESIGN: Population-based case-control study. SUBJECTS: A total of 496 incident MI cases and 518 population-based randomly selected controls matched to the cases by age (+/-5 years), gender, and county of residence. Subjects were interviewed with a validated food frequency questionnaire. Dietary patterns were identified by factor analysis. Odds ratios (OR) and 95% confidence intervals (CI) were obtained using multivariate conditional logistic regression adjusted for several recognized risk factors for MI. RESULTS: Two diet patterns were identified, 'vegetable' characterized by increased intake of vegetables and fruits, and 'staple', characterized by an increased use of palm oil for cooking, and intake of refined grains (mostly white rice and white bread), legumes, coffee, added sugar, and red meat. Compared to the lowest quintile of the staple diet pattern, the highest quintile was associated with an increased risk of MI (OR: 3.70, 95% CI: 2.30-5.97). Adjusting for potential confounders did not change the results (OR: 3.53, 95% CI: 1.98-6.31). Consistently, an increasing staple pattern score was associated with lower HDL cholesterol (P for trend <0.02) and alpha-linolenic acid in adipose tissue (P for trend <0.0001). The vegetable pattern was not associated with MI. CONCLUSIONS: The staple dietary pattern of Costa Rican adults is associated with low plasma HDL cholesterol, low alpha-linolenic acid in adipose tissue, and increased risk of MI.
PMID: 16465200 [PubMed - indexed for MEDLINE]
Modulatory effect of dietary factors on iron-induced in vivo lipid peroxidation in liver and serum of albino rats.
Ramachandran HD, Kusum R, Raina PL.
Department of Biochemistry and Nutrition, Central Food Technological Research Institute, Mysore 570 011, India. drr_chandran@yahoo.com
Effect of a computed diet based on cereals and spices incorporated with either crude palm oil (CPO)/soybean oil (SBO)/cod liver oil (CLO) at 10% level in the diet in modulating iron-induced in vivo lipid peroxidation was carried out during a 12 week study in albino rats. Three groups of rats, each divided into three sets were fed diets based on casein/ragi/jowar incorporated with CPO or SBO or CLO. The casein group of rats did not receive any spice mixture, while the ragi and jowar groups received spice mixture at 2.5% level. Serum lipid analysis showed significant increase in cholesterol, LDL-c + VLDL-c and decrease in HDL-c levels in all the iron treated group of animals. In liver, non-significant increase in total cholesterol triglyceride and decrease in phospholipid levels were noted. Fatty acid profile of liver tissue exhibited low 18:2 levels in various experimental groups due to peroxidation of membrane lipids. Histopathological examination of liver tissue in particular showed mild cytoplasmic vacuolation in control group of rats fed ragi/jowar and moderate vacuolation in all the iron-treated groups. The results demonstrate that different dietary components can beneficially modulate free radical mediated oxidative stress induced by lipid peroxidation.
PMID: 16430088 [PubMed - indexed for MEDLINE]
Linoleic acid-rich fats reduce atherosclerosis development beyond its oxidative and inflammatory stress-increasing effect in apolipoprotein E-deficient mice in comparison with saturated fatty acid-rich fats.
Sato M, Shibata K, Nomura R, Kawamoto D, Nagamine R, Imaizumi K.
Laboratory of Nutrition Chemistry, Division of Bioresource and Bioenvironmental Sciences, Graduate School, Kyushu University, Fukuoka 812-8581, Japan.
The relative benefit of replacing saturated fatty acid with linoleic acids is still being debated because a linoleic acid-enriched diet increases oxidative and inflammatory stresses, although it is associated with a reduction in serum cholesterol levels. The present study was conducted to evaluate the effect of dietary supplementation of linoleic acid-rich (HL) fat, compared with a saturated fatty acid-rich (SF) fat on atherosclerotic lesion areas, serum and liver cholesterol levels, oxidative stress (urinary isoprostanes and serum malondialdehayde) and inflammatory stress (expression of aortic monocyte chemoattractant protein-1; MCP-1) in apo E-deficient mice. Male and female apo E-deficient mice (8 weeks old; seven to eight per group) were fed an AIN-76-based diet containing SF fat (50 g palm oil and 50 g lard/kg) or HL fat (100 g high-linoleic safflower-seed oil/kg) for 9 weeks. Compared with the SF diet, the HL diet lowered atherosclerosis (P<0.05). It reduced serum total cholesterol levels (P<0.05), increased HDL-cholesterol levels (P<0.05) and lowered liver esterified cholesterol levels (P<0.01). The HL diet-fed mice showed increased expression of MCP-1 mRNA (P<0.05), serum levels of malondialdehayde (P<0.05) and urinary excretion of 2,3-dinor-5,6-dihydro-8-iso-prostaglandin F2alpha; P<0.05). These results suggest that having biomarkers in vivo for oxidative stress and inflammatory status of endothelial cells does not necessarily indicate predisposition to an increased lesion area in the aortic root in apo E-deficient mice fed an HL or SF diet.
PMID: 16351765 [PubMed - indexed for MEDLINE]
Palm oil versus hydrogenated soybean oil: effects on serum lipids and plasma haemostatic variables.
Pedersen JI, Muller H, Seljeflot I, Kirkhus B.
Institute of Basic Medical Sciences, Department of Nutrition, University of Oslo, P.O.Box 1046 Blindern, N-0316 Oslo, Norway. j.i.pedersen@basalmed.uio.no
The purpose of this study was to test if replacement of trans fatty acids by palmitic acid in an experimental margarine results in unfavourable effects on serum lipids and haemostatic factors. We have compared the effects of three different margarines, one based on palm oil (PALM-margarine), one based on partially hydrogenated soybean oil (TRANS- margarine) and one with a high content of polyunsaturated fatty acids (PUFA-margarine), on serum lipids in 27 young women. In nine of the participants fasting levels and diurnal postprandial levels of haemostatic variables on the 3 diets were compared. The sum of 12:0, 14:0, 16:0 provided 11% of energy (E%) in the PALM diet, the same as the sum of 12:0, 14:0, 16:0 and trans fatty acids in the TRANS-diet. Oleic acid provided 10-11E% in all three diets, while PUFA provided 5.7, 5.5 and 10.2 E%, respectively. Total fat provided 30-31% and the test margarines 26% of total energy in all three diets. Each of the diets was consumed for 17 days in a crossover design. There were no significant differences in total cholesterol, LDL-cholesterol and apoB between the TRANS- and the PALM-diet. HDL-cholesterol and apoA-I were significantly higher on the PALM-diet compared to the TRANS-diet while the ratio of LDL- to HDL-cholesterol was lower, although not significantly (P = 0.077) on the PALM-diet. Total cholesterol, LDL-cholesterol and apoB were significantly lower on the PUFA-diet compared to the two other diets. HDL-cholesterol was not different on the PALM- and the PUFA-diet while it was significantly lower on the TRANS-diet compared to the PUFA-diet. Triglycerides and Lp(a) were not different among the three diets. The diurnal postprandial state level of tissue plasminogen activator (t-PA) activity was significantly decreased on the TRANS-diet compared to the PALM-diet. t-PA activity was also decreased on the PUFA-diet compared to PALM-diet although not significantly (P=0.07). There were no significant differences in neither fasting levels or in circadian variation of t-PA antigen, PAI-1 activity, PAI-1 antigen, factor VII coagulant activity or fibrinogen between the three diets. Our results suggest that dietary palm oil may have a more favourable effect on the fibrinolytic system compared to partially hydrogenated soybean oil. We conclude that from a nutritional point of view, palmitic acid from palm oil may be a reasonable alternative to trans fatty acids from partially hydrogenated soybean oil in margarine if the aim is to avoid trans fatty acids. A palm oil based margarine is, however, less favourable than one based on a more polyunsaturated vegetable oil.
Publication Types:
PMID: 16326641 [PubMed - indexed for MEDLINE]
Different palm oil preparations reduce plasma cholesterol concentrations and aortic cholesterol accumulation compared to coconut oil in hypercholesterolemic hamsters.
Wilson TA, Nicolosi RJ, Kotyla T, Sundram K, Kritchevsky D.
Department of Health and Clinical Sciences, Center for Health and Disease Research, University of Massachusetts Lowell, Lowell, MA 01854-5125, USA.
Several studies have reported on the effect of refined, bleached and deodorized palm oil (RBD-PO) incorporation into the diet on blood cholesterol concentrations and on the development of atherosclerosis. However, very little work has been reported on the influence of red palm oil (RPO), which is higher in carotenoid and tocopherol content than RBD-PO. Thus, we studied the influence of RPO, RBD-PO and a RBD-PO plus red palm oil extract (reconstituted RBD-PO) on plasma cholesterol concentrations and aortic accumulation vs. hamsters fed coconut oil. Forty-eight F1B Golden Syrian hamsters (Mesocricetus auratus) (BioBreeders, Watertown, MA) were group housed (three/cage) in hanging polystyrene cages with bedding in an air-conditioned facility maintained on a 12-h light/dark cycle. The hamsters were fed a chow-based hypercholesterolemic diet (HCD) containing 10% coconut oil and 0.1% cholesterol for 2 weeks at which time they were bled after an overnight fast and segregated into four groups of 12 with similar plasma cholesterol concentrations. Group 1 continued on the HCD, Group 2 was fed the HCD containing 10% RPO in place of coconut oil, Group 3 was fed the HCD containing 10% RBD-PO in place of coconut oil and Group 4 was fed the HCD with 10% reconstituted RBD-PO for an additional 10 weeks. Plasma total cholesterol (TC) and non-high-density lipoprotein-cholesterol (HDL-C) (very low- and low-density lipoprotein) concentrations were significantly lower in the hamsters fed the RPO (-42% and -48%), RBD-PO (-32% and -36%) and the reconstituted RBD-PO (-37% and -41%) compared to the coconut oil-fed hamsters. Plasma HDL-C concentrations were significantly higher by 14% and 31% in hamsters fed the RBD-PO and RPO compared to the coconut oil-fed hamsters. Plasma triglyceride (TG) concentrations were significantly lower in hamsters fed RBD-PO (-32%) and the reconstituted RBD-PO (-31%) compared to the coconut oil-fed hamsters. The plasma gamma-tocopherol concentrations were higher in the coconut oil-fed hamsters compared to the hamsters fed the RPO (60%), RBD-PO (42%) and the reconstituted RBD-PO (49%), while for plasma alpha-tocopherol concentrations, the coconut oil-fed hamsters were significantly higher than only the RPO-fed hamsters (21%). The coconut oil-fed hamsters also had significantly higher plasma lipid hydroperoxide concentrations compared to RBD-PO (112%) and the reconstituted RBD-PO (485%). The hamsters fed the coconut oil diet excreted significantly more fecal total neutral sterols and cholesterol compared to the hamsters fed the RBD-PO (158% and 167%, respectively). The coconut oil-fed hamsters had significantly higher levels of aortic total, free and esterified cholesterol compared to the hamsters fed the RPO (74%, 50% and 225%, respectively), RBD-PO (57%, 48% and 92%, respectively) and the reconstituted RBD-PO (111%, 94% and 94%, respectively). Also, aortic free/ester cholesterol ratio in the aortas of hamsters fed RPO was significantly higher than in those fed the coconut oil (124%). In conclusion, hamsters fed the three palm oil preparations had lower plasma TC and non-HDL-C and higher HDL-C concentrations while accumulating less aortic cholesterol concentrations compared to hamsters fed coconut oil.
PMID: 16081272 [PubMed - indexed for MEDLINE]
[Effects of vegetal oil supplementation on the lipid profile of Wistar rats ]
[Article in Spanish]
Poveda E, Ayala P, Milena R, Ordonez E, Baracaldo C, Delgado W, Guerra M.
Grupo de Nutricion, Subdireccion de Investigacion, Instituto Nacional de Salud, Bogota, D.C., Colombia. epoveda@ins.gov.co
BACKGROUND: Dietary tocopherols, tocotrienols and saturated, mono and polyunsaturated fatty acids have been reported to have an effect on blood lipid profiles. In Colombia, vegetable oils (palm, soy, corn, sunflower, and canola) are a common dietary constituent and consumed in high quantities. OBJECTIVE: In the current study, the effects of vegetable oil consumption was examined by measuring blood concentrations of triglycerides (TG), total cholesterol (TC) and HDL cholesterol (HDL-C) in male Wistar rats. METHODS: The concentrations of tocopherols, tocotrienols, and fatty acids in each oil was quantified by High Performance Liquid Chromatography (HPLC). Each rat diet was supplemented with 0.2 ml/day with one oil type. Over a 4-week period, groups of animals were sacrificed weekly and blood samples were obtained to quantify TC, TG and HDL-C for each oil class. Statistical analyses included mean, standard deviation, ANOVA and Bonferroni comparisons tests. RESULTS: Triglyceride content was not affected except in the control and the soy group in the third treatment week, although a tendency for decreased TG was noted in the palm oil group and for increased TG in the sunflower oil and canola oil groups. No significant differences in total cholesterol were observed. In HDL-C, significant differences were present for every treatment week (p = 0.005); this represented a decreasing trend in palm oil group and an increasing trend in the sunflower and corn oil groups. CONCLUSION: The oils effected changes in the blood lipid profile. A small amount of saturated fatty acids (tocopherol and tocotrienol) were favourable for the HDL-C increase. The presenct of tocorienols tended to decrease the TG and probably helped attenuate the unfavorable effects of the saturated fatty acids.
PMID: 15962906 [PubMed - indexed for MEDLINE]
Lack of oxidative stress in a selenium deficient area in Ivory Coast--potential nutritional antioxidant role of crude palm oil.
Tiahou G, Maire B, Dupuy A, Delage M, Vernet MH, Mathieu-Daude JC, Michel F, Sess ED, Cristol JP.
Dept. of Biochemistry, Hospital Lapeyronie, 191 Avenue du Doyen Gaston Giraud, 34295 Montpellier cedex 5, France.
BACKGROUND: Previous studies have described an important selenium deficiency in a mountain region (Glanle) in the west of Ivory Coast. AIM OF THE STUDY: To assess the antioxidant capacity of subjects from a selenium deficient area in Ivory Coast (Glanle region). METHODS: This study involved 57 subjects, 18 to 69 years old, living in the Glanle region and 56 healthy controls living in the southern coastal region (Bodou). In the Glanle region families consume basically a vegetarian and crude palm oil diet, whereas in the Bodou region, families eat a fish-based diet with principally refined palm oil. Fasting blood samples were collected to assess the following parameters: lipid status (plasma total lipids; total-, HDL and LDL-cholesterol; triglycerides; phospholipids; fatty acid composition), plasma protein status (total protein, albumin, transthyretin, orosomucoid, CRP, transferrin), antioxidant capacity (plasma selenium, uric acid, retinol, alpha-tocopherol and tocotrienols levels, plasma seleno-glutathione peroxidase (GSHPx) activity) and oxidative stress markers (malondialdehyde (MDA) and advanced oxidation protein products (AOPP)). RESULTS: The mountain region samples (Glanle) were characterized by significantly lower plasma albumin, total-, HDL- and LDL-cholesterol, retinol and selenium levels, plasma PUFA content and GSHPx activity, but significantly higher alpha-tocopherol index and total tocotrienol level, than controls from the coastal area (Bodou). These results suggest a higher exposure risk to oxidative stress for the mountain region subjects. However, the absence of oxidative damage in this group provides evidence of a selenium independent protection mechanism against oxidative stress. This protection is related to lower plasma LDL cholesterol and PUFA content, and to higher alpha-tocopherol index, delta and total tocotrienols. CONCLUSION: The long-term consumption of crude palm oil could be considered as an effective protective factor against oxidative stress.
PMID: 15490200 [PubMed - indexed for MEDLINE]
-
Platelet aggregation, thromboxane production and thrombogenic ratio in postmenopausal women consuming high oleic acid-sunflower oil or palmolein.
Sanchez-Muniz FJ, Oubina P, Rodenas S, Benedi J, Cuesta C.
Departamento de Nutricion y Bromatologia I (Nutricion) Facultad de Farmacia, Universidad Complutense de Madrid, 28040, Madrid, Spain. frasan@farm.ucm.es
BACKGROUND: Saturated fatty acids exert controversial effects on platelet aggregation and eicosanoid production. AIM: To investigate the effect of a dietary exchange between palmitic acid and oleic acid on both platelet aggregation and thromboxane B2 (TXB(2)) production, and on urine TXB(2), prostacyclin I2 (PGI(2) as 6-keto-protaglandin F(1)alpha), and the thrombogenic ratio (TXB(2)/6-keto-protaglandin F(1)alpha) in fourteen postmenopausal women. EXPERIMENTAL DESIGN: Women were assigned to two consecutive 28-d dietary periods that were high in cholesterol (~400 mg/d) and fat (~46%en). In the first period all subjects followed an oleic acid-rich diet prepared with high oleic acidsunflower oil. This was followed by a second period rich in palmitic acid in the form of palmolein. DETERMINATIONS: Nutrient intakes, ADP-platelet aggregation, platelet TXB(2) production, urine TXB(2) and 6-keto-protaglandin F(1)alpha were measured during two dietary periods and the results obtained correlated to serum cholesterol, lipoproteincholesterol and peroxides, apolipoproteins and plasma tocopherol. RESULTS: The palmolein diet led to an increase in the platelet aggregation rate (p < 0.05) and in the time for the maximal aggregation rate (p < 0.02).No significant differences were observed in platelet TXB(2) production. Palmolein increased urine TXB(2) in pg/mL (p < 0.05) and pg/min (p < 0.01), whereas the thrombogenic ratio (TXB(2)/6-keto-protaglandin F(1)alpha) did not change. Most changes were related to oil change, few to serum cholesterol level (< or > or = 6.2 mmol/L) or age (< or > or = 65 yr). CONCLUSIONS: Palmolein diet activates platelet aggregation more in normocholesterolemics. Though palmolein increased thromboxane and tended to increase prostacyclin in urine in normo- and hypercholesterolemic women, the thrombogenic ratio did not change. These effects were related to the LDL and HDL concentration increases and to the absence of change in the total cholesterol/HDL-cholesterol ratio found following the dietary intervention.
Publication Types:
PMID: 14673602 [PubMed - indexed for MEDLINE]
Induction of fatal inflammation in LDL receptor and ApoA-I double-knockout mice fed dietary fat and cholesterol.
Zabalawi M, Bhat S, Loughlin T, Thomas MJ, Alexander E, Cline M, Bullock B, Willingham M, Sorci-Thomas MG.
Department of Pathology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
Atherogenic response to dietary fat and cholesterol challenge was evaluated in mice lacking both the LDL receptor (LDLr(-/-)) and apoA-I (apoA-I(-/-)) gene, LDLr(-/-)/apoA-I(-/-) or double-knockout mice. Gender- and age-matched LDLr(-/-)/apoA-I(-/-) mice were fed a diet consisting of 0.1% cholesterol and 10% palm oil for 16 weeks and compared to LDLr(-/-) mice or single-knockout mice. The LDLr(-/-) mice showed a 6- to 7-fold increase in total plasma cholesterol (TPC) compared to their chow-fed mice counterparts, while LDLr(-/-)/apoA-I(-/-) mice showed only a 2- to 3-fold increase in TPC compared to their chow-fed controls. This differential response to the atherogenic diet was unanticipated, since chow-fed LDLr(-/-) and LDLr(-/-)/apoA-I(-/-) mice began the study with similar LDL levels and differed primarily in their HDL concentration. The 6-fold diet-induced increase in TPC observed in the LDLr(-/-) mice occurred mainly in VLDL/LDL and not in HDL. Mid-study plasma samples taken after 8 weeks of diet feeding showed that LDLr(-/-) mice had TPC concentrations approximately 60% of their 16-week level, while the LDLr(-/-)/apoA-I(-/-) mice had reached 100% of their 16-week TPC concentration after only 8 weeks of diet. Male LDLr(-/-) mice showed similar aortic cholesterol levels to male LDLr(-/-)/apoA-I(-/-) mice despite a 4-fold higher VLDL/LDL concentration in the LDLr(-/-) mice. A direct comparison of the severity of aortic atherosclerosis between female LDLr(-/-) and LDLr(-/-)/apoA-I(-/-) mice was compromised due to the loss of female LDLr(-/-)/apoA-I(-/-) mice between 10 and 14 weeks into the study. Diet-fed female and, with time, male LDLr(-/-)/apoA-I(-/-) mice suffered from severe ulcerated cutaneous xanthomatosis. This condition, combined with a complete depletion of adrenal cholesterol, manifested in fatal wasting of the affected mice. In conclusion, LDLr(-/-) and LDLr(-/-)/apoA-I(-/-) mice showed dramatic TPC differences in response to dietary fat and cholesterol challenge, while despite these differences both genotypes accumulated similar levels of aortic cholesterol.
PMID: 12937162 [PubMed - indexed for MEDLINE]
Effect of palm olein oil in a moderate-fat diet on plasma lipoprotein profile and aortic atherosclerosis in non-human primates.
van Jaarsveld PJ, Smuts CM, Benade AS.
Nutritional Intervention Research Unit, Medical Research Council, Parow, South Africa. paul.van.jaarsveld@mrc.ac.za
Several studies have reported on the effect of palm olein oil (PO; palmitic acid content approximately 38%) incorporation into the diet on blood cholesterol concentration. Information on the effect of PO on atherosclerosis is, however, lacking. In vervet monkeys (Cercopithecus aethiops), low-density lipoprotein cholesterol (LDL-C) concen-trations can be modulated by the type and amount of fat in the diet. The vervet is a proven model for both the type and composition of human atherosclerotic lesions. The aim of this study was to determine the effect of PO in a moderate-fat moderate-cholesterol diet (MFD) on plasma lipoproteins and the progression of atherosclerosis in a non-human primate model after 25.5 months of dietary exposure. Thirty adult male vervets, never exposed to a Western-type atherogenic diet, were stabilised on a MFD (28%E fat; 26 mg cholesterol/1000 kJ) with a polyunsaturated to saturated fatty acid (P/S) ratio of 0.4 for six weeks. Baseline LDL-C, high-density lipoprotein (HDL)-C and bodyweight were used to stratify the vervets into three comparable groups of 10 each. One group continued with the MFD in which 11.0%E was derived from lard (AF). In the other two groups, the AF was substituted isocalorically with either sunflower oil (SO) or PO. Plasma lipids were measured at 6-monthly intervals and atherosclerosis was assessed in the aorta and in five peripheral arteries after 25.5 months of dietary exposure. The frequency of atherosclerosis in peripheral arteries and aortas was low. PO, relative to SO and AF, significantly reduced the risk for developing early lesions in peripheral arteries (P = 0.0277 and P = 0.0038, respectively) and, relative to AF, in aortas (P = 0.0335). The cholesterolaemic effect of MFD-PO was not significantly different from MFD-SO and MFD-AF. However, at 24 months the plasma total cholesterol concentration with MFD-AF was significantly higher than with MFD-SO (P = 0.0256). It is confirmed that a MFD with PO is no different from AF or SO in its cholesterolaemic effect. The anti-atherogenic efficacy of a MFD with PO, relative to SO and AF, was demonstrated in a non-human primate model of atherogenesis.
PMID: 12492629 [PubMed - indexed for MEDLINE]
Effect of palm olein oil in a moderate-fat diet on low-density lipoprotein composition in non-human primates.
van Jaarsveld PJ, Benade AJ.
Nutritional Intervention Research Unit, Medical Research Council, Parow, South Africa. paul.van.jaarsveld@mrc.ac.za
Plasma low-density lipoprotein cholesterol (LDL-C) concentrations in vervet monkeys (Cercopithecus aethiops) can be modulated by the type and amount of fat in the diet. There is, however, a paucity of information on the effect of different types and quantity of dietary fat on the plasma LDL composition in vervets. The objective of this study was to determine the effect of different sources of dietary fat on the concentrations and composition of circulating plasma LDL in vervets consuming moderate-fat diets containing either animal fat, sunflower oil or palm olein. Fifty adult male vervets, never exposed to a Western-type atherogenic diet, were randomly assigned to two groups. For 6 weeks 30 vervets were fed a moderate-fat (28%E) moderate-cholesterol (26 mg cholesterol/1000 kJ) diet (MFD) with a polyunsaturated to saturated fatty acid ratio (P/S) of 0.4; 20 vervets were fed a high-fat (34%E) high-cholesterol (98 mg cholesterol/1000 kJ) diet (HFD) with a P/S ratio of 0.6. Fasting blood samples were collected from all 50 vervets for plasma lipid measurements. The 30 vervets receiving the MFD were stratified into three comparable experimental groups of 10 each according to their LDL-C and high-density lipoprotein cholesterol (HDL-C) concentrations and bodyweight. One group continued with the MFD, in which 11%E was derived from lard (MFD-AF); in the other two groups the lard was substituted isocalorically with either sunflower oil (SO) (MFD-SO) or palm olein oil (PO) (MFD-PO). The three groups were fed the respective experimental diets for 24 months and LDL component concentrations and composition were assessed at 6-monthly intervals. In the long-term study the MFD-AF, MFD-SO and MFD-PO groups showed no significant time-specific group differences at 6, 12, 18 or 24 months with regard to the LDL component concentrations, composition, as well as the LDL molecular weight. As expected, after 6 weeks of dietary exposure the HFD group had significantly higher plasma and lipoprotein total cholesterol, LDL component and apolipoprotein AI concentrations, as well as a higher LDL-C : HDL-C ratio compared to the MFD group (P 0.0005). LDL particle size was not significantly different between the HFD and MFD groups, but the HFD group had significantly fewer triacylglycerol and significantly more unesterified cholesterol molecules per LDL particle compared to the MFD group (P 0.0018). PO in a MFD is no different from AF or SO in its effect on LDL component concentrations, composition or particle size. The increased LDL-C concentration seen with the HFD could be accounted for by a more than two-fold increase in the number of circulating LDL particles and not as a result of enrichment of particles with cholesterol.
PMID: 12492628 [PubMed - indexed for MEDLINE]
-
Transgenic overexpression of human lecithin: cholesterol acyltransferase (LCAT) in mice does not increase aortic cholesterol deposition.
Furbee JW Jr, Parks JS.
Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157-1040, USA.
Results from several atherosclerosis studies using morphometric procedures have proven controversial with regard to whether over-expression of human LCAT in transgenic (Tg) mice is atherogenic. The purpose of the present study was to determine the effect of 10-fold over-expression of human LCAT on aortic free and esterified cholesterol (EC) deposition as well as plasma lipoprotein cholesteryl ester (CE) fatty acid composition in mice fed an atherogenic diet containing cholic acid. C57Bl/6 (control) and human LCAT-Tg mice were fed chow or an atherogenic diet (15% of calories from palm oil, 1.0% cholesterol and 0.5% cholic acid) for 24 weeks before measurement of aortic cholesterol content. Compared with the chow diet, control and LCAT-Tg mice fed the atherogenic diet had a 2-fold increase in plasma total, free and EC, a 7-fold increase in plasma apoB lipoprotein cholesterol, and a 40-50-fold increase in hepatic cholesterol content. The aortic EC content was increased in control (0.7 vs. 1.2 mg/g protein) and LCAT-Tg (0.3 vs. 1.5 mg/g protein) mice fed the atherogenic diet compared with those consuming the chow diet; however, there was no difference in aortic free (14.4+/-6.8 vs. 18.5+/-7.7 mg/g protein) or esterified (1.2+/-1.0 vs. 1.5+/-1.2 mg/g protein) cholesterol content between atherogenic diet-fed control and LCAT-Tg mice, respectively. LCAT-Tg mice fed the atherogenic diet had a 2-fold increase in the ratio of saturated+monounsaturated to polyunsaturated CE species in plasma apoB lipoproteins compared with control mice (9.4+/-2.4 vs. 4.9+/-0.7). We conclude that over-expression of human LCAT in Tg mice fed an atherogenic diet containing cholic acid does not result in increased aortic cholesterol deposition compared with control mice, even though the CE fatty acid saturation index of plasma apoB lipoproteins was doubled.
PMID: 12208474 [PubMed - indexed for MEDLINE]
[Changes in of plasma lipoproteins after the use of palm oil in the diet of a group healthy adults]
[Article in Spanish]
Bosch V, Aular A, Medina J, Ortiz N, Apitz R.
Escuela de Nutricion y Dietetica, Universidad Central de Venezuela, Instituto Venezolano de Investigaciones Cientificas IVIC, Venezuela.
Although saturated fat acids have long known to have harmful effects on cholesterol and triacylglycerides levels in blood, new concepts have emerged form recent research on this matter. The purpose of this study was to know the effect of the consumption of palm olein on triacylglycerides and cholesterol levels as well as lipoprotein fractions in the blood plasma of healthy individuals from both sexes. MATERIALS AND METHODS: Different types of fats were administered for 12 weeks to 60 subjects, 45 male, 15 female, between 19 and 45 years of age, who were divided into three groups: the mix group (MG) was administered oil, margarine, and mayonnaise prepared with 50% olein; the olein group (OG) consumed fats prepared with 100% olein; and the control group (CG) consumed regular fats of customary use by the population. The diets provided 25 to 30% of calories. Blood samples were obtained for lipid analysis at the beginning and the end of the study. Plasma triacylglycerides and cholesterol concentrations were determined by means of enzyme and lipoprotein methods (VLDL, LDL; and HDL) by ultracentrifugation. RESULTS AND DISCUSSION: By comparing the groups' means no significant differences were found (p > 0.05) in blood lipids. Individual differences show a slight increase in VLDL-C in OG compared to MG and CG. No differences were found in LDL concentration. CONCLUSIONS: These results contribute evidence to differentiate between the effects of saturated vegetables oils, such as coconut oil, and of palm olein. The authors recommend not extrapolate the effects of type of oil to another in connection with TC increase in blood.
Publication Types:
PMID: 12184147 [PubMed - indexed for MEDLINE]
Palm oil: a healthful and cost-effective dietary component.
Ong AS, Goh SH.
Institute of Advanced Studies, University of Malaya, Kuala Lumpur, Malaysia.
Palm oil is an excellent choice for food manufacturers because of its nutritional benefits and versatility. The oil is highly structured to contain predominantly oleic acid at the sn2-position in the major triacylglycerols to account for the beneficial effects described in numerous nutritional studies. Oil quality and nutritional benefits have been assured for the variety of foods that can be manufactured from the oil directly or from blends with other oils while remaining trans-free. The oxidative stability coupled with the cost-effectiveness is unparalleled among cholesterol-free oils, and these values can be extended to blends of polyunsaturated oils to provide long shelf-life. Presently the supply of genetic-modification-free palm oil is assured at economic prices, since the oil palm is a perennial crop with unparalleled productivity. Numerous studies have confirmed the nutritional value of palm oil as a result of the high monounsaturation at the crucial 2-position of the oil's triacylglycerols, making the oil as healthful as olive oil. It is now recognized that the contribution of dietary fats to blood lipids and cholesterol modulation is a consequence of the digestion, absorption, and metabolism of the fats. Lipolytic hydrolysis of palm oil glycerides containing predominantly oleic acid at the 2 position and palmitic and stearic acids at the 1 and 3 positions allows for the ready absorption of the 2-monoacrylglycerols while the saturated free fatty acids remain poorly absorbed. Dietary palm oil in balanced diets generally reduced blood cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides while raising the high-density lipoprotein (HDL) cholesterol. Improved lipoprotein(a) and apo-A1 levels were also demonstrated from palm oil diets; an important benefits also comes from the lowering of blood triglycerides (or reduced fat storage) as compared with those from polyunsaturated fat diets. Virgin palm oil also provides carotenes apart from tocotrienols and tocopherols that have been shown to be powerful antioxidants and potential mediators of cellular functions. These compounds can be antithrombotic, cause an increase of the prostacyclin/thromboxane ratio, reduce restenosis, and inhibit HMG-CoA-reductase (thus reducing) cholesterol biosynthesis). Red palm oil is a rich source of beta-carotene as well as of alpha-tocopherol and tocotrienols.
Publication Types:
PMID: 11975364 [PubMed - indexed for MEDLINE]
Fatty acid saturation of the diet and plasma lipid concentrations, lipoprotein particle concentrations, and cholesterol efflux capacity.
Montoya MT, Porres A, Serrano S, Fruchart JC, Mata P, Gerique JA, Castro GR.
Fundacion Jimenez Diaz, Servicio de Bioquimica Clinica, Madrid, Spain.
BACKGROUND: The fatty acid content and saturation degree of the diet can modulate HDL composition and cholesterol efflux. OBJECTIVE: We studied the modifications in plasma lipoprotein particles and serum capacity to stimulate cholesterol efflux induced by different fatty acids. DESIGN: Seventeen women and 24 men followed in the same sequence 4 diets containing 35% of total energy as fat. The saturated fat diet contained 17% palm oil; the monounsaturated fat diet, 20.9% olive oil; the n-6 polyunsaturated fat diet, 12.5% sunflower oil; and the n-3 polyunsaturated fat diet, sunflower oil supplemented with 4-4.5 g fish oil/d. Each phase lasted 4-5 wk. RESULTS: In both sexes, apolipoprotein (apo) A-I concentrations were significantly lower with unsaturated fat diets than with the saturated fat diet, but concentrations of lipoproteins containing only apo A-I (Lp A-I) were lower only in the men. Concentrations of lipoproteins containing both apo A-I and apo A-II (Lp A-I:A-II) were lower with both polyunsaturated fat diets in the women but significantly higher in the men. Lp E concentrations were significantly higher with the 2 polyunsaturated fat diets. Lp E non-B particle concentrations were not modified in the men but were significantly higher in the women in both polyunsaturated fat phases. Lp C-III concentrations were higher with the saturated fat diet only in the men. The serum samples taken after the n-3 polyunsaturated fat phase were the most efficient for extracting cellular cholesterol in both sexes. CONCLUSIONS: The monounsaturated and polyunsaturated fat diets were healthier, producing a better lipid profile. The n-3 polyunsaturated fat diet increased the capacity of serum to promote the efflux of cholesterol from cells in culture.
Publication Types:
PMID: 11864853 [PubMed - indexed for MEDLINE]
Dietary fat saturation affects apolipoprotein AII levels and HDL composition in postmenopausal women.
Sanchez-Muniz FJ, Merinero MC, Rodriguez-Gil S, Ordovas JM, Rodenas S, Cuesta C.
Departamento de Nutricion, Universidad Complutense de Madrid, Madrid, Spain. frasan@farm.ucm.es
Increased HDL-cholesterol levels have been associated with lower coronary heart disease (CHD) risk. However, HDL are heterogeneous lipoproteins, and particles enriched in apolipoprotein (Apo) AII have been associated with increased CHD risk. We examined the effect of dietary intervention on HDL composition in 14 postmenopausal women subjected to two consecutive diet periods, i.e., an oleic acid sunflower oil diet followed by a palmolein diet, |