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1.
Findings from epidemiological and observational studies have indicated that diets high in omega-3 polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) may reduce the risk of cognitive decline and Alzheimer’s disease (AD). To determine if increasing intake of DHA and EPA through supplementation is beneficial to cognition and mood in individuals with cognitive impairment no dementia (CIND) or Alzheimer’s disease (AD) a four month, randomised, double-blind, placebo controlled study was conducted. Fifty-seven participants with CIND and nineteen with AD were randomised to receive either omega-3 PUFAs (600 mg EPA and 625 mg DHA per day) or placebo (olive oil) over a four month period. Elevating depleted levels of EPA and DHA through supplementation in individuals with CIND or AD was found to have negligible beneficial effect on their cognition or mood. These findings confirm an overall negligible benefit of omega-3 PUFA supplementation for those with cognitive impairment and dementia. More intervention studies need to be undertaken with longer study durations and larger sample sizes. It may prove fruitful to examine effects of different doses as well as effects in other dementia subtypes.  相似文献   

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The administration of tetradecylthioacetic acid (TTA), a hypolipidemic and anti-inflammatory modified bioactive fatty acid, has in several experiments based on high fat diets been shown to improve lipid transport and utilization. It was suggested that increased mitochondrial and peroxisomal fatty acid oxidation in the liver of Wistar rats results in reduced plasma triacylglycerol (TAG) levels. Here we assessed the potential of TTA to prevent tumor necrosis factor (TNF) α-induced lipid modifications in human TNFα (hTNFα) transgenic mice. These mice are characterized by reduced β-oxidation and changed fatty acid composition in the liver. The effect of dietary treatment with TTA on persistent, low-grade hTNFα overexpression in mice showed a beneficial effect through decreasing TAG plasma concentrations and positively affecting saturated and monounsaturated fatty acid proportions in the liver, leading to an increased anti-inflammatory fatty acid index in this group. We also observed an increase of mitochondrial β-oxidation in the livers of TTA treated mice. Concomitantly, there were enhanced plasma levels of carnitine, acetyl carnitine, propionyl carnitine, and octanoyl carnitine, no changed levels in trimethyllysine and palmitoyl carnitine, and a decreased level of the precursor for carnitine, called γ-butyrobetaine. Nevertheless, TTA administration led to increased hepatic TAG levels that warrant further investigations to ascertain that TTA may be a promising candidate for use in the amelioration of inflammatory disorders characterized by changed lipid metabolism due to raised TNFα levels.  相似文献   

4.
Docosahexaenoic acid (DHA) supply to the fetal brain depends upon the dam’s dietary intake of n-3 fats. In this study, we measured the incorporation of DHA into the fetal brain and liver in n-3 fatty acid deficient (0.1% alpha-linolenate) mice upon switching to an n-3 fatty acid adequate (2.1% alpha-linolenate) diet. Second generation mice raised and maintained on an n-3 deficient diet during mating were switched to an n-3 adequate diet on embryonic day 1 (ED 1) or ED 13. Fatty acid analysis was performed on fetal brains and livers and on maternal serum on ED 13, 15, 17, and 19. Although fetal brain and liver DHA began at a very low level (both exhibited an 85% decline), recovery was nearly complete by ED 15 in the group switched near conception but thereafter diverged. The maternal serum and fetal liver were very similar in their DHA and docosapentaenoic acid time courses. However, when repletion began on ED 13, brain DHA recovery was only about 44%. These results suggest that a nutritional intervention with alpha-linolenic acid can nearly but incompletely rescue the mouse fetal DHA deficiency if began at the time of conception but that the third trimester is too late, thus leaving a large DHA gap.  相似文献   

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Duncan RE  Archer MC 《Lipids》2008,43(7):619-627
Obesity is associated with impaired fatty acid (FA) oxidation and increased de novo hepatic lipogenesis that may contribute to the development of hypertriglyceridemia, an important risk factor for the development of cardiovascular disease. Strategies to improve hepatocyte FA metabolism, including dietary interventions, are therefore important for the prevention of obesity-associated co-morbidities. Farnesol is consumed in the diet as a component of plant products. In the present study, we administered farnesol orally to rats for seven days and found significantly reduced serum triglyceride concentrations compared with controls. Potential mechanisms underlying the hypotriglyceridemic effect of farnesol were investigated using clone-9 cultured rat hepatocytes. Farnesol significantly upregulated expression of peroxisome proliferator-activated receptor alpha (PPARalpha) and the PPARalpha-regulated genes fatty acyl-CoA oxidase and carnitine palmitoyl transferase 1a, suggesting that increased hepatic FA oxidation may contribute to serum triglyceride lowering in rats. Farnesol did not change SREBP-1c mRNA levels, but significantly down-regulated fatty acid synthase (FAS) mRNA and protein levels and activity, indicating that attenuated lipogenesis may also contribute to hypotriglyceridemic effects of farnesol in vivo. Rescue experiments revealed that down-regulation of FAS by farnesol was not related to activation of PPARalpha, but rather was caused by a 9-cis retinoic acid mediated mechanism that involved down-regulation of retinoid X receptor beta. Diets rich in plant products are associated with a lower risk of cardiovascular disease. Our findings suggest that farnesol may contribute to this protective effect by lowering serum TG levels.  相似文献   

7.
To evaluate the antioxidant and immune effects of low molecular yeast β-glucan on mice, three sulfated glucans from Saccharomyces cerevisiae (sGSCs) with different molecular weight (MW) and degrees of sulfation (DS) were prepared. The structures of the sGSCs were analyzed through high performance liquid chromatography-gel permeation chromatography (HPLC-GPC) and Fourier transform infrared spectroscopy (FTIR). sGSC1, sGSC2, and sGSC3 had MW of 12.9, 16.5 and 19.2 kDa, respectively, and DS of 0.16, 0.24 and 0.27, respectively. In vitro and in vivo experiments were conducted to evaluate the antioxidant and immunological activities of the sGSCs. In vitro experiment, the reactive oxygen species (ROS) scavenging activities were determined. In vivo experiment, 50 male BALB/c mice were divided into five groups. The sGSC1, sGSC2 and sGSC3 treatment groups received the corresponding sGSCs at 50 mg/kg/day each. The GSC (glucans from Saccharomyces cerevisiae) treatment group received 50 mg/kg/day GSC. The normal control group received equal volume of physiological saline solution. All treatments were administered intragastrically for 14 day. Results showed that sGSC1, sGSC2 and sGSC3 can scavenge 1,1-diphenyl-2-picryl-hydrazyl (DPPH), superoxide, and hydroxyl radicals in vitro. The strength of the radical scavenging effects of the sGSCs was in the order of sGSC1 > sGSC2 > sGSC3. Oral administration of sGSC1 significantly improved serum catalase (CAT) and glutathione peroxidase (GSH-Px) activities and decreased malondialdehyde (MDA) level in mice. sGSC1 significantly improved the spleen and thymus indexes and the lymphocyte proliferation, effectively enhanced the percentage of CD4+ T cells, decreased the percentage of CD8+ T cells, and elevated the CD4+/CD8+ ratio. sGSC1 significantly promoted the secretion of IL-2 and IFN-γ. These results indicate that sGSC1 with low MW and DS has better antioxidant and immunological activities than the other sGSCs, and sGSC1 could be used as a new antioxidant and immune-enhancing agent.  相似文献   

8.
Analysis of MCPD esters and glycidyl esters in vegetable oils using the indirect method proposed by the DGF gave inconsistent results when salting out conditions were varied. Subsequent investigation showed that the method was destroying and reforming MCPD during the analysis. An LC time of flight MS method was developed for direct analysis of both MCPD esters and glycidyl esters in vegetable oils. The results of the LC–TOFMS method were compared with the DGF method. The DGF method consistently gave results that were greater than the LC–TOFMS method. The levels of MCPD esters and glycidyl esters found in a variety of vegetable oils are reported. MCPD monoesters were not found in any oil samples. MCPD diesters were found only in samples containing palm oil, and were not present in all palm oil samples. Glycidyl esters were found in a wide variety of oils. Some processing conditions that influence the concentration of MCPD esters and glycidyl esters are discussed.  相似文献   

9.
The effect of calcium glutarate (Cagt) and calcium pimelate (Capt) on the formation of β crystalline form in isotactic polypropylene (iPP) after isothermal crystallization at 130°C for 30 min has been investigated. The maximum KWAXD and KDSC values were 31.97% and 38.06%, respectively, for iPP doped with 0.2 wt.% Cagt. The maximum values of KWAXD and KDSC were 73.60% and 68.44% for iPP doped with 0.3 wt.% and 0.15 wt.% Capt, respectively. The crystal size of iPP doped with Capt is finer than that of iPP doped with Cagt. It is shown that the β nucleation ability of Capt is superior to that of Cagt. The difference in the β nucleation ability between Cagt and Capt is explained by the structural difference of the nucleators with β-iPP.  相似文献   

10.
《Journal of Catalysis》2002,205(1):58-66
The influence of treatment with an NaAlO2 aqueous solution of NaAlO2 on the surface acid properties of zeolite β was studied as a method to increase the number of both Brønsted and Lewis acid sites. The Hβ samples, prepared by treating with an aqueous solution of NaAlO2, were characterized by XRD, NH3-TPD, pyridine-IR, 29Si MAS NMR, and 27Al MAS NMR. The surface properties of the Hβ zeolite changed after treatment with the aqueous NaAlO2 solution: the number of strong and weak acid sites, the total amount of acid, and the Brønsted and Lewis acid sites increased. The treatment of zeolite β with an aqueous solution of NaAlO2 may realuminate an Si(0Al)A site by the isomorphous substitution of Al(OH)4 anions.  相似文献   

11.
The effects of dietary sesamin on the hepatic metabolism of arachidonic (AA) and eicosapentaenoic (EPA) acids, were investigated with respect to their β-oxidation and secretion as triacylglycerol (TG). For 2 wk, rats were fed three types of dietary oils: (i) corn oil (control) group; (ii) FPA group: FPA ethyl esters/rapeseed oil=2∶3; (iii) AA group: AA ethyl esters/palm oil/perilla oil=2∶2∶1, with or without 0.5% (w/w) of sesamin. Dietary sesamin significantly increased the activities of hepatic mitochondrial and peroxisomal fatty acid oxidation enzymes (mitochondrial carnitine acyltransferase I, acyl-CoA dehydrogenase, and peroxisomal acyl-CoA oxidase). Dietary FPA increased mitochondrial carnitine acyltransferase I and peroxisomal acyl-CoA oxidase. Dietary AA, however, had an effect on peroxisomal acyl-CoA oxidase only. In whole liver and the TG fraction, EPA and AA concentrations were significantly increased by dietary EPA and AA, respectively, and were decreased by dietary sesamin. In hepatic mitochondria and peroxisomes, EPA concentration was increased by dietary EPA, but AA was not changed by dietary AA. The addition of dietary sesamin to the EPA-supplemented diet significantly decreased the EPA concentration compared to concentrations found with consumption of dietary EPA alone. These results suggest that sesamin increased β-oxidation enzyme activities and reduced hepatic EPA and AA concentrations by degradation. The stimulating effect of sesamin on β-oxidation, however, was more significant in the EPA group than in the AA group. Hepatic AA concentration was altered by the joint effect of sesamin through esterification into TG and the stimulation of β-oxidation.  相似文献   

12.
Although blending polyunsaturated oil with more saturated or monounsaturated oils has been studied extensively, there is no similar information regarding the partial replacement of palm olein with olive oil (OO). Therefore the main objective of this study was to investigate the effects of OO partial replacement (0, 25, 50, 75, 90 and 100% w/w) on the chemical stability of palm olein oil (POO). The physicochemical properties of oil samples namely iodine value, peroxide value (PV), anisidine value, TOTOX value (total oxidation value, TV), free fatty acid (FFA), cloud point, color and viscosity were considered as response variables. Significant differences among the oil blend properties were determined at the significance level of P < 0.05. Apart from FFA, all the response variables were significantly influenced by type and concentration of oils. The oil blend containing 10% POO and 90% OO showed the highest TV (6.10); whereas the blend containing 90% POO and 10% OO exhibited the least TV (2.41). This study indicated that the chemical stability of oil blend significantly (P < 0.05) increased with increasing the proportion of polyunsaturated/monounsaturated fatty acid.  相似文献   

13.
Using advanced electron paramagnetic resonance techniques (EPR), oxidation of crude vegetable oils and their components (fatty acids and triglycerides) by radicals generated from hydrogen peroxide was investigated. The correlation rotational times were determined allowing us to characterize radicals formed during edible oils oxidation. Additionally 1H- and 14N-hyperfine coupling constants differentiate the fatty acids dependently on their unsaturation. The acids with a higher number of unsaturated bonds exhibit higher AN values of PBN/·lipid adduct. The waste oil with high free fatty acids content underwent the oxidation reaction more efficiently, however due to saturation and the high content of the fatty acids the carbon-centered radicals formed (upon hydrogen peroxide radicals) and their PBN (N-tert-butyl-α-phenylnitrone) adducts were less stable. The antioxidant effect was dependent on the amount of α-tocopherol added. In small amounts of up to 0.35 mg/1 g of fatty acid or triglyceride, it inhibited the creation of PBN/·lipid adducts while with higher amounts it intensified adduct formation. The α-tocopherol (AT) addition influence was also studied as spin scavenging dependence and indicated that any addition of the antioxidant in the investigated samples led to free radical scavenging and the effect increased with the increase in AT content.  相似文献   

14.
In the present paper, the effect of β-cyclodextrin (β-CD) inclusion complexation on the solubility and enzymatic hydrolysis of naringin was investigated. The inclusion complex of naringin/β-CD at the molar ratio of 1:1 was obtained by the dropping method and was characterized by differential scanning calorimetry. The solubility of naringin complexes in water at 37 ± 0.1 °C was 15 times greater than that of free naringin. Snailase-involved hydrolysis conditions were tested for the bioconversion of naringin into naringenin using the univariate experimental design. Naringin can be transformed into naringenin by snailase-involved hydrolysis. The optimum conditions for enzymatic hydrolysis were determined as follows: pH 5.0, temperature 37 °C, ratio of snailase/substrate 0.8, substrate concentration 20 mg·mL−1, and reaction time 12 h. Under the optimum conditions, the transforming rate of naringenin from naringin for inclusion complexes and free naringin was 98.7% and 56.2% respectively, suggesting that β-CD complexation can improve the aqueous solubility and consequently the enzymatic hydrolysis rate of naringin.  相似文献   

15.
Three temperature-sensitive monolithic columns were prepared by atom transfer radical polymerization and oxidation–reduction method using the initiator systems of CCl4/FeCl2, BPO/DMA, and APS/TEMED, respectively. The three monoliths were characterized by scanning electron microscopy, nitrogen adsorption, and thermogravimetric analysis. The obtained monolithic columns were used as on-line solid phase extraction sorbent coupled with high-performance liquid chromatography for the enrichment of β-sitosterol. By comparing some influencing factors on the adsorption, the optimum temperature-sensitive monolithic column which was initiated by CCl4/FeCl2 was selected for enrichment of β-sitosterol from plant oil. The maximum adsorption capacity of the monolith for β-sitosterol was 10.0031 mg/g. The limit of detection and limit of quantitation were 0.039 and 0.13 mg/mL, respectively. The recovery was in the range of 90.21–98.26%. The results showed that the monolith had better selectivity for β-sitosterol and could be used for enrichment of β-sitosterol in food samples. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47683.  相似文献   

16.
In traditional Chinese medicine, shikonin and its derivatives, has been used in East Asia for several years for the prevention and treatment of several diseases, including cancer. We previously identified that β,β-dimethylacrylshikonin (DA) could inhibit hepatocellular carcinoma growth. In the present study, we investigated the inhibitory effects of DA on human colorectal cancer (CRC) cell line HCT-116 in vitro and in vivo. A viability assay showed that DA could inhibit tumor cell growth in a time- and dose-dependent manner. Flow cytometry showed that DA blocks the cell cycle at G(0)/G(1) phase. Western blotting results demonstrated that the induction of apoptosis by DA correlated with the induction of pro-apoptotic proteins Bax, and Bid, and a decrease in the expression of anti-apoptotic proteins Bcl-2 and Bcl-xl. Furthermore, treatment of HCT-116 bearing nude mice with DA significantly retarded the growth of xenografts. Consistent with the results in vitro, the DA-mediated suppression of HCT-116 xenografts correlated with Bax and Bcl-2. Taken together, these results suggest that DA could be a novel and promising approach to the treatment of CRC.  相似文献   

17.
Docosahexaenoic acid (DHA) is considered to be important for cardiac and brain function, and 17β-estradiol (E2) appears to increase the conversion of α-linolenic acid (ALA) into DHA. However, the effect of varying ALA intake on the positive effect of E2 on DHA synthesis is not known. Therefore, the objective of this study was to investigate the effects of E2 supplementation on tissue and serum fatty acids in mice fed a low-ALA corn oil-based diet (CO, providing 0.6 % fatty acids as ALA) or a high ALA flaxseed meal-based diet (FS, providing 11.2 % ALA). Ovariectomized mice were implanted with a slow-release E2 pellet at 3 weeks of age and half the mice had the pellet removed at 7 weeks of age. Mice were then randomized onto either the CO or FS diet. After 4 weeks, the DHA concentration was measured in serum, liver and brain. A significant main effect of E2 was found for liver and serum DHA, corresponding to 25 and 15 % higher DHA in livers of CO and FS rats, respectively, and 19 and 13 % in serum of CO and FS rats, respectively, compared to unsupplemented mice. There was no effect of E2 on brain DHA. E2 results in higher DHA in serum and liver, at both levels of dietary ALA investigated presently, suggesting that higher ALA intake may result in higher DHA in individuals with higher E2 status.  相似文献   

18.
In this work, multiwall-carbon-nanotubes (MWCNTs), β nucleating agent(TMB-5) and isotactic polypropylene(iPP) were mixed to prepare MWCNTs/iPP composites, which were processed by a corotating twin screw extruder at 270 °C. MWCNTs at 0 wt%, 0.05 wt%, 0.3 wt%, 1 wt%, 2 wt% and 3 wt% were added into the composites respectively and the concentration of TMB-5 was 0.3 wt% consistently. Polarized light microscopy (POM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and Wide-angle X-ray diffraction (WAXD) were used to study the dispersion of MWCNTs in the β-Nucleated iPP and the crystallization of the composites. SEM and TEM graphs showed that MWCNTs dispersed individually in the iPP matrix when TMB-5 was added in the composites. In the contrast, there were many aggregates of MWCNTs in iPP matrix without TMB-5. DSC and WAXD results indicate that TMB-5 and individual MWCNTs have a synergistic effect on inducing the formation of β crystals. However, with the content of MWCNTs increasing in the composites, β crystal content decreased and α crystal content increased, which indicated that MWCNTs aggregating in the iPP matrix acted as α nucleating agent restricting the formation of β crystals and the effect of TMB-5 on dispersion became limited at a relatively high MWCNTs content.  相似文献   

19.
Patients with cystic fibrosis, caused by mutations in CFTR, exhibit specific and consistent alterations in the levels of particular unsaturated fatty acids compared with healthy controls. Evidence suggests that these changes may play a role in the pathogenesis of this disease. Among these abnormalities are increases in the levels of n-7 and n-9 fatty acids, particularly palmitoleate (16:1n-7), oleate (18:1n-9), and eicosatrienoate or mead acid (20:3n-9). The underlying mechanisms of these particular changes are unknown, but similar changes in the n-3 and n-6 fatty acid families have been correlated with increased expression of fatty acid metabolic enzymes. This study demonstrated that cystic fibrosis cells in culture exhibit increased metabolism along the metabolic pathways leading to 16:1n-7, 18:1n-9, and 20:3n-9 compared with wild-type cells. Furthermore, these changes are accompanied by increased expression of the enzymes that produce these fatty acids, namely Δ5, Δ6, and Δ9 desaturases and elongases 5 and 6. Taken together, these findings suggest that fatty acid abnormalities of the n-7 and n-9 series in cystic fibrosis are as a result, at least in part, of increased expression and activity of these metabolic enzymes in CFTR-mutated cells.  相似文献   

20.
Ketonization of valeric acid, which can be obtained by lignocellulosic biomass conversion, was carried out in a fixed bed flow reactor over ZrO2, 5–20 % CeO2/ZrO2 and CeO2 both under hydrogen and nitrogen stream at 628 K and atmospheric pressure. Regardless gas-carrier 10 wt% CeO2/ZrO2 was found to show higher catalytic activity compared to zirconia per se as well as other ceria modified zirconia while ceria per se exhibited very low catalytic activity. All catalysts provided higher acid conversion in H2 than in N2 whereas selectivity to 5-nonanone was insensitive to gas atmosphere. XRD, FTIR, UV–Vis DRS, XPS, HRTEM methods were applied to characterize catalysts in reduced and unreduced states simulating corresponding reaction conditions during acid ketonization. XRD did not reveal any changes in zirconia and ceria/zirconia lattice parameters as well as crystalline phase depending on gas atmosphere while insertion of ceria in zirconia caused notable increase in lattice parameter indicating some distortion of crystalline structure. According to XPS, FTIR and UV–Vis methods, the carrier gas was found to affect catalyst surface composition leading to alteration in Lewis acid sites ratio. Appearance of Zr3+ cations was observed on the ZrO2 surface after hydrogen pretreatment whereas only Zr4+ cations were determined using nitrogen as a gas-carrier. These changes of catalyst’s surface cation composition affected corresponding activity in ketonization probably being crucial for reaction mechanism involving metal cations catalytic centers for acid adsorption and COO? stabilization at the initial step.  相似文献   

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