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1.
The purpose of this study was to assess the effect of fish oil with or without vitamin E on plasma vitamin antioxidants. Thirty-three
apparently healthy women aged 18–28 yr were recruited from the university environs, and 30 completed the double-blinded, parallel
design supplementation trial. Blood samples were collected at baseline (week 0) and following 28 d of supplementation with
three capsules/d (0.8 g×3) of either fish oil (FO) or FO with vitamin E (3 IU/g) (FOE). An additional blood sample was taken
at day 91 (washout). Plasma antioxidant vitamins, fatty acid composition, and lipid peroxides were measured. Plasma α-tocopherol
concentrations were increased significantly in both groups postsupplementation FO (P=0.018) and FOF (P=0.003) compared with baseline and washout values. Plasma retinol concentration was significantly increased (P=0.034) compared with baseline and washout values following supplementation with FOE but not FO, while plasma β-carotene was
significantly increased (P=0.036), compared with baseline and washout values, following supplementation with FO but not FOE. There was a trend (P=0.059) toward decreased plasma ascorbic acid following FO supplementation compared with baseline and washout. Plasma lipid
peroxides did not change following either supplementation. Results suggest that low-dose FO feeding with and without vitamin
E differentially modulates plasma antioxidant vitamins but has no significant effect on lipid peroxidation. 相似文献
2.
Apolipoprotein E allele 4 (apo ɛ4) and smoking each have been associated with an unfavorable lipid profile. We used data collected on 1,472 subjects in the
National Heart, Lung, and Blood Institute Family Heart Study to assess whether smoking interacts with apo ɛ4 to influence the levels of plasma lipids. We dichotomized smoking and apo ɛ4 and used analysis of covariance to estimate the means of lipids. Smokers had lower body mass index, were younger, and consumed
less fruits and vegetables. Among individuals without apo ɛ4, comparing nonsmokers with smokers, mean low density lipoprotein cholesterol (LDL) was 129.3 and 134.4 mg/dL, respectively,
for women and 126.1 and 127.6 mg/dL, respectively, for men. Among subjects with an apo ɛ4 allele, corresponding means were 132.0, and 152.9 mg/dL, respectively, for women and 131.3 and 137.3 mg/dL, respectively,
for men (P for interaction <0.001 for women and 0.11 for men). A similar interaction was observed for total cholesterol among women
(P=0.02). This study shows a statistically significant effect modification of the relation of apo ɛ4 to LDL and total cholesterol by smoking among women. Smoking may enhance genetic susceptibility to an unfavorable lipid profile
among subjects with apo ɛ4. 相似文献
3.
CLA refers to isomers of octadecadienoic acid with conjugated double bonds. The most abundant form of CLA (rumenic acid (RA):
c9,t11-18∶2) is found in milk and beef fat. Further, CLA supplements containing RA and t10,c12−18∶2 are now available. Consumption of commercially produced CLA has been shown to decrease adipose accretion in growing
laboratory and production animals and cause milk fat depression in cows. We tested the hypothesis that CLA supplementation
would increase milk CLA concentration and decrease milk fat content in humans. Breastfeeding women (n=9) participated in this double-blind, placebo-controlled, crossover study divided into three periods: intervention l (5 d),
washout (7 d), and intervention II (5 d). Women were randomized to treatment order. During each intervention period, women
consumed 1.5 g of CLA supplement or placebo (olive oil) daily; during the washout period, no supplements were consumed. Milk
was collected by complete breast expression on the final day of each period; milk output was estimated by 24-h weighing on
the penultimate day of each intervention period. Milk RA and t10,c12−18∶2 concentrations were greater (P<0.05) during the CLA treatment period as compared to the placebo period. Milk fat content was significantly lower during
the CLA treatment, as compared to the placebo treatment (P<0.05). Data indicate no effect of treatment on milk output. Therefore, it would be prudent that lactating women not consume
commercially available CLA supplements at this time.
This paper was published in part in Masters, N., McGuire, M.A., and McGuire, M.K. (1999) Conjugated Linoleic Acid Supplementation
and Milk Fat Content in Humans, FASEB J. 13, A697. 相似文献
4.
The purpose of this study was to investigate in healthy humans the effect of eicosapentaenoic acid (EPA) and docosahexaenoic
acid (DHA) intake, alone or in combination with dL-α-tocopherol acetate (vitamin E) supplements on lipid peroxidation. Eightly
men were randomly assigned in a double-blind fashion to take daily for 6 wk either menhaden oil (6.26 g, n−3 fatty acids)
or olive oil supplements with either vitamin E (900 IU) or its placebo. Antioxidant vitamins, phospholipid composition, malondialdehyde
(MDA), and lipid peroxides were measured in the plasma at baseline and week 6. At the same time, breath alkane output was
measured. Plasma α-tocopherol concentration increased in those receiving vitamin E (P<0.0001). In those supplemented with n−3 fatty acids, EPA and DHA increased in plasma phospholipids (P<0.0001) and plasma MDA and lipid peroxides increased (P<0.001 and P<0.05, respectively). Breath alkane output did not change significantly and vitamin E intake did not prevent the increase
in lipid peroxidation during menhaden oil supplementation. The results demonstrate that supplementing the diet with n−3 fatty
acids resulted in an increase in lipid peroxidation, as measured by plasma MDA release and lipid peroxide products, which
was not suppressed by vitamin E supplementation. 相似文献
5.
Orlistat is a lipase inhibitor that is applied for treating obesity. Lipases are required for digestion and absorption of
dietary lipids and fat-soluble vitamins and carotenoids. The aim of this study was to compare the effects of orlistat therapy
on plasma concentrations of oxygenated (β-cryptoxanthin, lutein/zeaxanthin) and hydrocarbon (α-, β-carotene, lycopene) carotenoids.
Six patients with a body mass index (BMI)≥30 kg/m2 received 360 mg/d orlistat over 4.5 mon. Plasma carotenoid concentrations were determined at baseline (T
0) and after 3 (T
3) and 4.5 mon (T
4.5) along with anthropometric, dietary, and biochemical indices, including plasma lipids, retinol, α- and γ-tocopherols, and
FA. Baseline BMI was 32.7±1.97 kg/m2. Five of six patients lost weight; the average weight loss was 3.6±2.4% (P=0.47). There were no significant changes in dietary carotenoid intakes. In contrast, plasma α-and β-carotene concentrations
decreased significantly from T
0 to T
4.5 by 45% (P=0.006) and 32% (P=0.013), respectively. Plasma lycopene decreased from T
0 to T
3 but increased again from T
3 to T
4.5, while β-cryptoxanthin and lutein/zeaxanthin concentrations did not change. There were no significant alterations in tocopherol,
retinol, and FA concentrations. In conclusion, even though weight loss was not significant, orlistat therapy was associated
with significant decreases in plasma concentrations of the highly lipophilic hydrocarbon carotenoids, α- and β-carotene. 相似文献
6.
Supplementation with conjugated linoleic acid (CLA) induces a number of physiological effects in experimental animals, including
reduced body fat content, decreased aortic lipid deposition, and improved serum lipid profile. Controlled trials on the effects
of CLA in humans have hitherto been scarce. The aim of this study was to evaluate the effects of supplementation with CLA
in healthy humans on anthropometric and metabolic variables and on the fatty acid composition of serum lipids and thrombocytes.
Fifty-three healthy men and women, aged 23–63 yr, were randomly assigned to supplementation with CLA (4.2 g/d) or the same
amount of olive oil during 12 wk in a double-blind fashion. The proportion of body fat decreased (−3.8%, P<0.001) in the CLA-treated group, with a significant difference from the control group (P=0.050). Body weight, body mass index, and sagittal abdominal diameter were unchanged. There were no major differences between
the groups in serum lipoproteins, nonesterified fatty acids, plasma insulin, blood glucose, or plasminogen activator inhibitor
1 (PAI-1). In the CLA group the proportions of stearic, docosatetraenoic, and docosapentaenoic acids increased in serum lipids
and thrombocytes, while proportions of palmitic, oleic, and dihomoγ-linolenic acids decreased, causing a decrease of the estimated
Δ-6 and Δ-9 and an increase in the Δ-5 desaturase activities. These results suggest that supplementation with CLA may reduce
the proportion of body fat in humans and that CLA affects fatty acid metabolism. No effects on body weight, serum lipids,
glucose metabolism, or PAI-1 were seen. 相似文献
7.
Effect of low-to-moderate amounts of dietary fish oil on neutrophil lipid composition and function 总被引:8,自引:0,他引:8
Although essential to host defense, neutrophils are also involved in numerous inflammatory disorders including rheumatoid
arthritis. Dietary supplementation with relatively large amounts of fish oil [containing >2.6 g eicosapentaenoic acid (EPA)
plus 1.4 g docosahexaenoic acid (DHA) per day] can attenuate neutrophil functions such as chemotaxis and superoxide radical
production. In this study, the effects of more moderate supplementation with fish oil on neutrophil lipid composition and
function were investigated. The rationale for using lower supplementary doses of fish oil was to avoid adverse gastrointestinal
problems, which have been observed at high supplementary concentrations of fish oil. Healthy male volunteers aged <40 yr were
randomly assigned to consume one of six dietary supplements daily for 12 wk (n=8 per treatment group). The dietary supplements included four different concentrations of fish oil (the most concentrated
fish oil provided 0.58 g EPA plus 1.67 g DHA per day), linseed oil, and a placebo oil. The percentages of EPA and DHA increased
(both P<0.05) in neutrophil phospholipids in a dose-dependent manner after 4 wk of supplementation with the three most concentrated
fish oil supplements. No further increases in EPA or DHA levels were observed after 4 wk. The percentage of arachidonic acid
in neutrophil phospholipids decreased (P<0.05) after 12 wk supplementation with the linseed oil supplement or the two most concentrated fish oil supplements. There
were no significant changes in N-formyl-met-leu-phe-induced chemotaxis and superoxide radical production following the dietary supplementations. In conclusion,
low-to-moderate amounts of dietary fish oil can be used to manipulate neutrophil fatty acid composition. However, this may
not be accompanied by modulation of neutrophil functions such as chemotaxis and superoxide radical production. 相似文献
8.
Aldo Ferretti Joseph T. Judd Rachel Ballard-Barbash Padmanabhan P. Nair Philip R. Taylor Beverly A. Clevidence 《Lipids》1991,26(7):500-503
We investigated the effect of fish oil supplementation on the synthesis of prostaglandin E (PGE)in vivo by measuring the excretion of its catabolite, PGE-M, in 24-hr urine by gas chromatography/mass spectrometry. Forty healthy
male volunteers (24–57 years of age) consumed a controlled basal diet providing 40% of energy from fat (P/S ratio about 0.8∶1),
130 mg/1000 kcal cholesterol, and a minimum of 22 mg/day of α-tocopherol (α-T), for three experimental periods lasting a total
of 28 weeks. During period 1 (10 weeks) the diet was supplemented with placebo (PO) capsules (15×1 g/day) consisting of a
blend of fats approaching the fatty acid profile of the basal diet. This was followed by a second 10-week period during which
the subjects received 15×1 g/day capsules of fish oil concentrate (FOC). During period 3 (8 weeks) they continued the 15 g/day
intake of FOC but received an additional 200 mg/day of α-T. PO and FOC capsules contained 1 mg α-T/g fat as antioxidant. A
14% reduction of PGE-M excretion was observed after 10 weeks of FOC supplementation (period 2), compared to an identical period
of placebo supplementation (period 1), P=0.009. PGE-M excretion during the last week of period 3 was not significantly different
from that at the end of period 2. The reduction in PGE synthesis in response to the relatively high marine oil supplementation
was large in many subjects participating in this study. 相似文献
9.
Supplementation with CLA: Isomer incorporation into serum lipids and effect on body fat of women 总被引:5,自引:5,他引:0
Animal studies have suggested that CLA, a natural component of meat and dairy products, may confer beneficial effects on health.
However, human studies using supplementation with CLA have produced contradictory results. The aim of the present study was
to further investigate the effect of CLA supplementation on human body fat, serum leptin, and serum lipids, as well as the
incorporation of CLA isomers into serum lipids classes. Sixteen young healthy nonobese sedentary women received 2.1 g of CLA
(divided equally between the cis,trans-9,11 and trans,cis-10,12 isomers) daily for 45 d and placebo for 45 d in a randomized double-blind crossover design. Body fat was estimated
(by measurement of skinfold thickness at 10 sites), and blood was sampled at the beginning, middle, and end of the entire
intervention period; an additional blood sample was obtained 2 wk thereafer. No significant differences in energy, carbohydrate,
lipid, or protein intake existed between the CLA and placebo intake periods. No significant differences were found in body
fat or serum leptin, TAG, total cholesterol, HDL-cholesterol, and alanine aminotransferase between CLA and placebo. The CLA
isomer content of serum TAG, phospholipids, and total lipids increased 2–5 times with CLA supplementation (P<0.05). In contrast, the CLA content of cholesteryl esters did not change significantly. The period of 2 wk after the end
of CLA supplementation was sufficient for its washout from serum lipids. These data indicate that supplementation with 2.1
g of CLA daily for 45 d increased its levels in blood but had no effect on body composition or the lipidemic profile of nonobese
women. 相似文献
10.
Fish oil supplementation of lactating mothers affects cytokine production in 2 1/2-year-old children
n−3 PUFA influence immune functioning and may affect the cytokine phenotype during development. To examine whether maternal
fish oil supplementation during lactation could modify later immune responses in children, 122 lactating Danish mothers with
a fish intake below the population median were randomized to groups supplemented for the first 4 mon of lactation with 4.5
g/d of fish oil (equivalent to 1.5 g/d of n−3 long-chain PUFA) or olive oil. Fifty-three mothers with a fish intake in the
highest quartile of the population were also included. The FA composition of erythrocyte membranes was measured at 4 mon and
at 2 1/2 yr. Plasma immunoglobulin E (IgE) levels and cytokine production in lipopolysaccharide-stimulated whole-blood cultures
were determined at 2 1/2 yr. Erythrocyte n−3 PUFA at 4 mon were higher in infants from the fish oil group compared with the
olive oil group (P<0.001) but were no longer different at 2 1/2 yr. The median production of lipopolysaccharide-induced interferon γ(IFN-γ)
in the fish oil group was fourfold higher than that in the olive oil group (P=0.034), whereas interleukin-10 (IL-10) production was similar. The IFN-γ/IL-10 ratio was twofold higher in the fish oil group
(P=0.019) and was positively correlated with 20∶5n−3/20∶4n−6 in erythrocytes at 4 mon (P=0.050). The percentages of atopic children and plasma IgE were not different in the two groups, but the study was not designed
to look at atopy. Cytokine responses and erythrocyte FA composition in children of mothers with a high fish intake were intermediate
in comparison with those in the randomized groups. Fish oil supplementation during lactation resulted in increased in vitro IFN-γ production in the children 2 yr after the supplementation was given, which may reflect a faster maturation of the immune
system. 相似文献
11.
The aim of this research was to investigate the effect of fish oil supplementation, in the third trimester of pregnancy and
early lactation period of healthy pregnant Danish women. Forty-four pregnant women were randomly allocated to fish oil supplementation
(1.3 g EPA and 0.9 g DHA per day) from week 30 of gestation (FO-group) or to a control regimen (olive oil or no oil; controls).
The FO-group was randomly subdivided into women stopping fish oil supplementation at delivery [FO(pregn)], and women continuing
supplementation for an, additional 30 d [FO(pregn/lact)]. Thirty-six women agreed to collect milk samples at days 4, 16, and
30 postpartum. The FA composition of the milk samples was determined by GLC. At days 4, 16, and 30 in lactation, FO(pregn/lact)
women (n=12) had, respectively 2.3 (P=0.001), 4.1 (P=0.001), and 3.3 (P=0.001) times higher mean contents of LCPUFA(n−3) in their breast milk compared with controls (n=13), and 1.7 (P=0.005), 2.8 (P=0.001), and 2.8 (P=0.001), times higher LCPUFA(n−3) contents, respectively, at these days compared with FO(pregn) women (n=11). The latter group did not differ significantly from controls with regard to LCPUFA(n−3) content in the breast milk. Similar
results were obtained when analyzing separately for effects on the milk content of DHA. Dietary supplementation with 2.7 g
LCPUFA(n−3) per day from week 30 of gestation and onward more than tripled the LCPUFA(n−3) content in early breast milk; supplementation
limited to pregnancy only was much less effective. 相似文献
12.
Fitó M Gimeno E Covas MI Miró E López-Sabater Mdel C Farré M de lT Marrugat J 《Lipids》2002,37(3):245-251
It is generally believed that virgin olive oil consumption has beneficial effects, but little is known about its effects postprandially
on oxidant/antioxidant status. The aim of this study was to determine changes in oxidative stress biomarkers and lipid profile
after a single dose of virgin olive oil and after 1 wk of daily consumption. Sixteen subjects (9 men, 7 women) ingested 50
mL of virgin olive oil in a single dose. Blood samples were collected from 0 to 24 h. Thereafter, 14 participants (8 men,
6 women) followed a 1-wk 25 mg/d virgin olive oil dietary intervention. Blood samples were collected at the end of this period.
Serum TAG (P=0.016), plasma FA (P<0.001) and lipid peroxidation products in plasma (P<0.001) and VLDL (P=0.007) increased, reaching a peak at 4–6 h, and returning to baseline values at 24 h after oil ingestion. The opposite changes
were observed in plasma glutathione peroxidase (P=0.001) and glutathione reductase (GR) (P=0.042). No changes in LDL lipid peroxidation or resistance to oxidation were observed postprandially. At 24 h, plasma oleic
acid remained increased (P<0.05) and resistance of LDL to oxidation improved (P<0.05). After 1 wk of virgin olive oil consumption, plasma oleic acid (P=0.031), resistance of LDL to oxidation (P<0.05), and plasma GR activity (P=0.005) increased. These results indicate that changes in oxidant/antioxidant status occur after oral virgin olive oil. Virgin
olive oil consumption could provide short-term benefits for LDL resistance to oxidation and in glutathione-related enzyme
activities. 相似文献
13.
To assess the validity of two techniques used to measure human cholesterol synthesis, the rate of uptake of deuterium (D)
into plasma free cholesterol (FC), and plasma cholesterol precursor (squalene, lanosterol, desmosterol and lathosterol) levels
were compared in 14 women [65–71 yr with low density lipoprotein-cholesterol (LDL-C)≥3.36 mmol·l
−1]. Subjects consumed each of six diets for 5-wk periods according to a randomized crossover design. The experimental diets
included a baseline diet (39% energy as fat, 164 mg chol·4.2 MJ−1) and five reduced-fat diets (30% of energy as fat), where two-thirds of the fat was either soybean oil; squeeze, tub or stick
margarines; or butter. Fractional and absolute synthesis rates (FSR and ASR) of FC were determined using the deuterium incorporation
(DI) method, while cholesterol precursor levels were measured using gas-liquid chromatography. Data were pooled across diets
for each variable and correlation coefficients were calculated to determine if associations were present. There was good agreement
among levels of the various cholesterol precursors. In addition, FSR in pools/d (p·d−1) and ASR in grams/d (g·d−1) were strongly associated with lathosterol (r=0.72 and 0.71, P=0.0001), desmosterol (r=0.75 and 0.75, P=0.0001), lanosterol (r=0.67 and 0.67), and squalene (r=0.69 and 0.68) when levels of the precursors were expressed as μmol·mmol−1C. Significant but lower correlations were observed between the D uptake and plasma cholesterol precursor levels when the
latter were expressed in absolute amounts (μmol·L−1). The wide range of fatty acid profiles of the experimental diets did not influence the degree of association between methods.
In conclusion, the DI method and levels of some cholesterol precursors correspond as methods for shortterm measurement of
cholesterol synthesis. 相似文献
14.
G. E. Onibi J. R. Scaife I. Murray V. R. Fowler 《Journal of the American Oil Chemists' Society》1998,75(2):189-198
Thirty-two pigs were allocated to one of four diets, FFRD0 and FFRD200, containing full-fat rapeseed (FFR), 150 g/kg [25–50
kg liveweight (LW)], and 250 g/kg (50–90 kg LW), or CD0 and CD200, containing equivalent quantities of rapeseed meal and 34
g/kg (25–50 kg LW) or 59.2 g/kg (50–90 kg LW) coconut oil and lard (0.5:0.5, w/w). Diets FFRD200 and CD200 were supplemented
with 200 mg/kg α-tocopherol acetate (ATA). ATA supplementation significantly (P<0.001) reduced muscle drip loss. The melting point (°C) of subcutaneous fat was significantly lowered by FFR (P<0.001) but increased by ATA supplementation (P<0.05). Tissue α-tocopherol (AT) concentrations were significantly increased by ATA supplementation. Longissimus dorsi AT concentration was positively correlated with AT concentration in subcutaneous fat (r=0.86) and in plasma at 35 (r=0.65) and 77 (r=0.85) days of feeding (P<0.001). In both L. dorsi and subcutaneous adipose tissue lipids, FFRD caused a significant (P<0.001) decrease in the ratio of n-6 to n-3 fatty acids and a significant (P<0.001) increase in the ratio of polyunsaturated to saturated fatty acids. AT supplementation significantly reduced the susceptibility
of L. dorsi and subcutaneous fat to lipid oxidation during storage at 4°C for up to 16 d. For all dietary treatments and storage times,
lipid oxidation [mg malondialdehyde (MDA)/kg muscle] was greater in the surface layer (0–2.5 mm) of L. dorsi than below the surface (2.5–5 mm). Oxidative stability of L. dorsi lipids to iron-induced lipid peroxidation was significantly improved (P<0.001) by AT supplementation. Meat from pigs fed FFRD diets was significantly less stable to iron-induced oxidation (nmoles
MDA/mg protein) at the longer incubation periods (100 and 200 min). The susceptibility of L. dorsi to iron-induced lipid oxidation decreased as the ratio of the tissue concentration of AT to unsaturated fatty acid increased. 相似文献
15.
Donald F. Steenson David B. Min 《Journal of the American Oil Chemists' Society》2000,77(11):1153-1160
The relative oxidative stability of soybean oil samples containing either thermally degraded β-carotene or lycopene was determined
by measuring peroxide value (PV) and headspace oxygen depletion (HOD) every 4 h for 24 h. Sobyean oil samples containing 50
ppm degraded β-carotene that were stored in the dark at 60°C displayed significantly (P<0.01) higher HOD values compared with controls. Lycopene degradation products (50 ppm) in soybean oil significantly (P<0.05) decreased HOD of samples when stored in the dark. PV and HOD values for samples containing 50 ppm of either β-carotene
or lycopene degradation products stored under lighted conditions did not differ significantly from controls (P<0.05). However, soybean oil samples containing 50 ppm of unheated, all-trans β-carotene or lycopene stored under light showed significantly lower PV and HOD values than controls (P<0.01). These results indicated that during autoxidation of soybean oil held in the dark, β-carotene thermal degradation products
acted as a prooxidant, while thermally degraded lycopene displayed antioxidant activity in similar soybean oil systems. In
addition, β-carotene and lycopene degradation products exposed to singlet oxygen oxidation under light did not increase or
decrease the oxidative stability of their respective soybean oil samples. 相似文献
16.
Monica L. Assunção Haroldo S. Ferreira Aldenir F. dos Santos Cyro R. CabralJr Telma M. M. T. Florêncio 《Lipids》2009,44(7):593-601
The effects of dietary supplementation with coconut oil on the biochemical and anthropometric profiles of women presenting
waist circumferences (WC) >88 cm (abdominal obesity) were investigated. The randomised, double-blind, clinical trial involved
40 women aged 20–40 years. Groups received daily dietary supplements comprising 30 mL of either soy bean oil (group S; n = 20) or coconut oil (group C; n = 20) over a 12-week period, during which all subjects were instructed to follow a balanced hypocaloric diet and to walk
for 50 min per day. Data were collected 1 week before (T1) and 1 week after (T2) dietary intervention. Energy intake and amount
of carbohydrate ingested by both groups diminished over the trial, whereas the consumption of protein and fibre increased
and lipid ingestion remained unchanged. At T1 there were no differences in biochemical or anthropometric characteristics between
the groups, whereas at T2 group C presented a higher level of HDL (48.7 ± 2.4 vs. 45.00 ± 5.6; P = 0.01) and a lower LDL:HDL ratio (2.41 ± 0.8 vs. 3.1 ± 0.8; P = 0.04). Reductions in BMI were observed in both groups at T2 (P < 0.05), but only group C exhibited a reduction in WC (P = 0.005). Group S presented an increase (P < 0.05) in total cholesterol, LDL and LDL:HDL ratio, whilst HDL diminished (P = 0.03). Such alterations were not observed in group C. It appears that dietetic supplementation with coconut oil does not
cause dyslipidemia and seems to promote a reduction in abdominal obesity. 相似文献
17.
Serum HDL cholesterol (HDL-C) is inversely associated with coronary artery disease, ischemic stroke, and atherosclerosis in
men and women. Among postmenopausal women, oral conjugated equine estrogen (CEE) increases serum HDL-C. This is due to activation
of hepatic nuclear estrogen receptors, resulting in increased HDL-C expression, as well as modulation of proteins which metabolize
HDL-C. 2-methoxyestradiol (2-MeOE2), an estrogen metabolite, has several vasculoprotective effects and may play a role in
HDL-C production. 2-MeOE2 inhibits HMG-CoA reductase in vitro but no study has examined the relationship between serum 2-MeOE2
and serum HDL-C. A population-based sample provided information regarding demographic characteristics and use of antihyperlipidemic
medications. Serum was analyzed for 17β-estradiol (E2), estrogen metabolites (EMs), and lipoproteins. Results included serum
EM data from 51 men and 47 postmenopausal women. Preliminary analysis revealed no correlation between 2-MeOE2 and serum HDL-C
in men so the current analysis includes only women (N = 40) with no missing demographic, medication, EM, or lipoprotein data. Linear regression revealed that serum 2-MeOE2 and
antihyperlipidemic medications were positively associated with serum HDL-C (β = 0.276, P = 0.043, and β = 0.307, P = 0.047, respectively) when age, race/ethnicity, and body mass index were held constant. Prospective studies are needed to
determine if 2-MeOE2 is causally related to HDL-C in women. 相似文献
18.
Vitamin E supplementation could elevate circulating vitamin E metabolites while modulating oxidative and inflammatory status
in end-stage renal failure patients undergoing hemodialysis. Plasma concentrations of carboxyethyl-hydroxychromanols (α-and
γ-CEHC), ascorbic acid, α-and γ-tocopherols, E2-isoprostanes, and inflammatory biomarkers [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), ferritin, and C-reactive
protein (CRP)] were measured in blood samples obtained from patients (n=11) before and after dialysis on two occasions prior to, and at 1 and 2 mon of daily vitamin E supplementation (400 IU RRR-α-tocopherol). Supplementation nearly doubled plasma α-tocopherol concentrations (from 18±0.5 to 31±1.7 μM, P<0.0001), whereas γ-tocopherol concentrations decreased (from 2.8±0.3 to 1.7±0.2 μM, P=0.001). Serum α-CEHC increased 10-fold from 68±3 to 771±175 nM (P<0.0001), and γ-CEHC increased from 837±164 to 1136±230 nM (P=0.008). Vitamin E supplementation also increased postdialysis hematocrits from 38±1% to 41±1% (P<0.001). Dietary antioxidant intakes (vitamins E and C) were low in most subjects; plasma ascorbic acid levels (88±27 μM)
decreased significantly with dialysis (33±11 μM, P=0.01). Plasma Il-6, CRP, TNF-α, and free F2-isoprostane concentrations were elevated throughout the study. There is a complex relationship between chronic inflammation
and oxidative stress that is not mitigated by short-term vitamin E supplementation. Importantly, serum vitamin E metabolite
concentrations that increased 10-fold within 30 d of supplementation did not increase further, suggesting routes other than
urine for removal of metabolites. 相似文献
19.
Cheek cells (buccal epithelia) were utilized as a noninvasive index of fatty acid status in a study of the effects of n−3
long chain polyunsaturated fatty acid supplementation on visual function in preterm infants. The fatty acid profile of cheek
cell phospholipids was directly correlated with the dietary docosahexenoic acid (DHA) intake of infants receiving: (i) primarily
human milk; (ii) n−3 fatty acid-deficient, corn oil-based, commercial formula (CO); (iii) α-linolenic acid-enriched, soy oilbased,
commercial formula; or (iv) experimental formula enriched with soy and marine oils providing a DHA level equivalent to that
in human milk. In a subset of infants with complete cheek cell fatty acid profiles and visual function assessments, preterm
infants at both 36 wk (n=63) and 57 wk (n=45) postconceptional age had significantly (P<0.0005) reduced cheek cell phospholipid DHA levels in the n−3-dificient, CO-fed group compared to the other diet groups.
The DHA content in cheek cell phospholipids was highly correlated (P<0.0005) with that of both red blood cell lipids and plasma phospholipids at the 36-and 57-wk time points. The DHA content
in cheek cell lipids of infants at 36 wk was significantly correlated with electroretinographic responses (r=−0.29; P<0.03) and visual acuity (r=−0.31; P<0.02) as measured by visual-evoked potentials (VEP). Cheek cell DHA was highly correlated (r=−0.57; P<0.0005) with VEP acuity at the 57-wk time point. These results suggest that the fatty acid profile of cheek cells is a valid
index of essential fatty acid status, can be monitored frequently, and is associated with functional parameters in infants. 相似文献
20.
Neil J. Mann Stella L. O’Connell Kylie M. Baldwin Indu Singh Barbara J. Meyer 《Lipids》2010,45(8):669-681
Fish are a rich source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two long-chain polyunsaturated n-3 fatty
acids (LC n-3 PUFA) with cardiovascular benefits. A related but less-investigated LC n-3 PUFA, docosapentaenoic acid (DPA),
is more common in seal oil and pasture-fed red meats. This study compared indicators of platelet function and plasma lipids
in healthy volunteers given supplements containing these different fatty acids (FA) for 14 days. Subjects, randomised into
three groups of ten, consumed capsules of tuna oil (210 mg EPA, 30 mg DPA, 810 mg DHA), seal oil (340 mg EPA, 230 mg DPA,
450 mg DHA) or placebo (sunola) oil. Supplementary LC n-3 PUFA levels were approximately 1 g/day in both fish and seal oil
groups. Baseline dietary FA and other nutrient intakes were similar in all groups. Both fish and seal oil elevated platelet
DHA levels (P < 0.01). Seal oil also raised platelet DPA and EPA levels (P < 0.01), and decreased p-selectin (P = 0.01), a platelet activation marker negatively associated with DPA (P = 0.03) and EPA (P < 0.01) but not DHA. Plasma triacylglycerol decreased (P = 0.03) and HDL-cholesterol levels increased (P = 0.01) with seal oil only. Hence, seal oil may be more efficient than fish oil at promoting healthy plasma lipid profiles
and lowering thrombotic risk, possibly due to its high DPA as well as EPA content. 相似文献