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101.
Oxidized low-density lipoprotein (ox-LDL)-induced oxidative injury in vascular endothelial cells is crucial for the progression of cardiovascular diseases, including atherosclerosis. Several flavonoids have been shown cardiovascular protective effects. Recently, our research group confirmed that the novel flavonoids isolated from the deep-sea-derived fungus Arthrinium sp., 2,3,4,6,8-pentahydroxy-1-methylxanthone (compound 1) and arthone C (compound 2) effectively scavenged ROS in vitro. In this study, we further investigated whether these compounds could protect against ox-LDL-induced oxidative injury in endothelial cells and the underlying mechanisms. Our results showed that compounds 1 and 2 inhibited ox-LDL-induced apoptosis and adhesion factors expression in human umbilical vein vascular endothelial cells (HUVECs). Mechanistic studies showed that these compounds significantly inhibited the ROS level increase and the NF-κB nuclear translocation induced by ox-LDL. Moreover, compounds 1 and 2 activated the Nrf2 to transfer into nuclei and increased the expression of its downstream antioxidant gene HO-1 by inducing the phosphorylation of AKT in HUVECs. Importantly, the AKT inhibitor MK-2206 2HCl or knockdown of Nrf2 by RNA interference attenuated the inhibition effects of these compounds on ox-LDL-induced apoptosis in HUVECs. Meanwhile, knockdown of Nrf2 abolished the effects of the compounds on ox-LDL-induced ROS level increase and the translocation of NF-κB to nuclei. Collectively, the data showed that compounds 1 and 2 protected endothelial cells against ox-LDL-induced oxidative stress through activating the AKT/Nrf2/HO-1 pathway. Our study provides new strategies for the design of lead compounds for related cardiovascular diseases treatment.  相似文献   
102.
甜叶菊提取液对星斑川鲽生长性能和生理生化指标的影响   总被引:1,自引:0,他引:1  
试验采用添加甜叶菊提取液的饲料饲喂星斑川鲽56d后,进行形体、生长和生理生化指标的测.定,结果表明,添加甜叶菊提取液显著提高了饲料系数、高密度脂蛋白含量及超氧化物歧化酶活性,对其他指标无显著影响。  相似文献   
103.
红松仁蛋白对实验小鼠血脂代谢的影响   总被引:1,自引:0,他引:1  
利用高脂饲料建立实验小鼠模型,然后灌胃不同剂量的红松仁蛋白,4周后检测血清中总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)及高密度脂蛋白胆固醇(HDL-C)的含量.结果表明,红松仁蛋白能明显降低肥胖小鼠血清中TC、TG、LDL-C的含量,升高HDL-C的含量,红松仁蛋白对肥胖小鼠具有降血脂的作用.  相似文献   
104.
前后做了2个试验.试验Ⅰ选用80只60周龄海兰褐商品蛋鸡,随机分为1个对照组(CK)和4个处理组(T1、T2、T3、T4).处理组T1、T2分别在日粮中添加质量分数为0.4×10- 6和0.8×10- 6(以Cr计)的无机氯化铬(CrC13·6H2O);处理组T3、T4分别在日粮中添加质量分数为0.4×10- 6和0.8×10- 6(以Cr计)的铬酵母(Cryeast, Cr-Y).试验Ⅱ选用90只55周龄父母代种用蛋鸡,同样分成1个CK 组和4个处理组(t1、t2、t3、t4).处理组t1,t2分别在日粮中添加质量分数为0.4×10- 6和0.8×10- 6(以Cr计)的Cr-Y;t3,t4分别在日粮中添加质量分数为0.4×10- 6和0.8×10- 6(以Cr计)的烟酸铬(Cr nicotinate, Cr-Nic).2个试验均为期1个月.结果表明,日粮补充无机Cr或有机Cr对产蛋鸡各项生产性能未见明显影响,但于试验未,添加有机Cr组的蛋黄胆固醇质量分数和血清总胆固醇水平均比CK组和无机Cr组显著降低,而血清高密度脂蛋白胆固醇水平则有所提高;有机Cr组中质量分数为0.8×10- 6的与0.4×10- 6的相比,前者作?  相似文献   
105.
Arctic char (Salvelinus alpinus L.) were fed over a three-week period with a commercial diet or one of seven casein-based diets. The latter were either lipid-free or supplemented with 50–200 g linseed oil kg–1 diet by dry weight, 160 g linseed oil and 40 g 14:0 or 160 g linseed oil and 40 g 16:0. Three fish having filled guts were sampled from each dietary group and analysed for ultrastructural changes in the pyloric caecum.Increasing the dietary lipid level increased the accumulation of lipid droplets in columnar absorptive enterocytes from about 9% of epithelial volume in fish fed a diet of 50 g linseed oil, to almost 61% in fish fed a diet of 200 g linseed oil. Replacing linseed oil in the diet with 14:0 (160 g linseed oil + 40 g 14:0 kg–1 diet) appeared to produce a smaller lipid loading (roughly 53%) but the difference was not statistically significant. However, replacing 40 g linseed oil with 40 g of 16:0 in the diet decreased lipid loading significantly to just under 10%. Epithelial damage to enterocytes was assessed using a ranking scale based on ultrastructural signs of cell and organelle swelling and degeneration. The extent of damage closely followed the level of lipid loading, being lowest in fish fed the lipid-free or low-lipid (damage index 0.07–0.13) diets, and highest in char maintained on a diet containing 200 g linseed oil (index 1.41). Replacing linseed oil with 14:0 (160 g linseed oil + 40 g 14:0) appeared to reduce the damage index to 0.77 but this was not significant. However, a significant reduction of the damage index to 0.27 was observed when linseed oil was replaced by 16:0.We conclude that higher dietary linseed oil promotes lipid droplet accumulation in enterocytes. The droplets are probably related to the amount of polyunsaturated fatty acids in the lipid. Intracellular droplet formation and cellular damage are both reduced by adding saturated fatty acids to the diet. This could be related to disruptions in the lipoprotein assembly rate. The cellular damages observed with high lipid diets are likely to be pathological and may lead to intestinal malfunction and represent a major infection route for pathogenic bacteria.  相似文献   
106.
苜蓿总黄酮对小鼠脂类代谢及氧自由基的影响   总被引:2,自引:0,他引:2  
试验结果显示:灌胃给予苜蓿总黄酮(TFA)的小鼠全血中甘油三酯(TG)和低密度脂蛋白胆固醇(LDL—C)的含量明显降低(P〈0.05),而高密度脂蛋白胆固醇(HDL—C)含量升高,而且其肝脏和肾脏组织匀浆中过氧化物歧化酶(SOD)的活性显著升高(P〈0.05),丙二醛(MDA)的含量降低。因此得出结论:TFA具有降血脂、降低低密度脂蛋白胆固醇含量、预防和减轻动脉硬化的作用;同时也具有抑制氧自由基损伤、防止脂质过氧化的作用。  相似文献   
107.
The antioxidative effect of the carotenoids phytoene and phytofluene in biological systems has not yet been studied. We therefore sought to investigate the effect of these carotenoids, isolated from the alga Dunaliella bardawil, in a biological system and used the in vitro low density lipoprotein (LDL) oxidation method to assay their antioxidative effects. We found that similar to beta-carotene and alpha-tocopherol, a carotenoid algal preparation containing phytoene and phytofluene inhibited LDL oxidation. These findings and the presence of phytoene and phytofluene in human tissues suggest that they can be part of the defense system against oxidative stress.  相似文献   
108.
This study investigated the effects of dietary phosphatidylcholine (PC) at different growth stages of Litopenaeus vannamei (L. vannamei) with an initial weight of 0.70 ± 0.00 g (juvenile) and 4.25 ± 0.00 g (subadult) for 8 weeks. Six isonitrogenous and isoenergetic diets containing PC (0, 1.7, 5.1, 6.8, 10.2 and 13.6 g/kg) were confected using formulated with redfish meal, dehulled soybean meal and peanut meal as protein source, fish oil and corn oil as fat source. The juveniles were reared in 0.3 m3 aquarium at the density of 40 in triplicates, as well as the subadults in 0.5 m3 at the density of 40 in triplicates. Results showed PC level had significant effects on weight gain rate (WGR), specific growth rate, feed conversion ratio in juvenile and subadult shrimps and hepatosomatic index in juvenile shrimps (< 0.05). No significant differences were found in moisture, whole body protein and crude ash (> 0.05). Crude fat of juveniles had no significant change (> 0.05), but subadults increased significantly (< 0.05). Both juveniles and subadults showed that triglyceride and low‐density lipoprotein presented a downward trend with PC elevating, but high‐density lipoprotein increased gradually. Cholesterol in juveniles presented upward, but downward in subadults (p < 0.05). Dietary PC also significantly reduced the aspartate transaminase in juveniles and alanine transaminase in subadults (< 0.05). PC supplementation significantly improved the glutathione S‐transferase activity and reduced the content of malondialdehyde in the hepatopancreas (< 0.05). PC supplementation significantly improved gill filament sodium‐potassium adenosine triphosphatase enzyme of juvenile shrimps (< 0.05), but subadult shrimps were not influenced (> 0.05). PC supplementation significantly elevated the content of hepatopancreas eicosapentaenoic acid, highly unsaturated fatty acid (HUFA) and n‐3HUFA (< 0.05), but the content of linoleic acid significantly reduced (< 0.05). The broken‐line and quadratic regression model based on WGR showed the optimum dietary PC requirement was 10.3 g/kg and 6.5 g/kg for juveniles and subadults, respectively.  相似文献   
109.
AIM:To explore the role of phosphatidylinositiol 3-kinase/protein kinase B/endothelial nitric oxide synthase (PI3K/Akt/eNOS) signaling pathways in the inhibitory effects of puerarin on oxidized low-density lipoprotein (ox-LDL)-induced tissue factor (TF) expression in vascular endothelial cells.METHODS:The mRNA expression of TF was detected by real-time fluorescent quantitative PCR.The protein levels of TF and Akt was determined by Western blot.The content of the nitric oxide (NO) was measured by nitrate reduction method.RESULTS:Compared with control group,incubating endothelial cells with ox-LDL significantly induced TF expression at mRNA and protein levels and the dephosphorylation of Akt protein,and decreased NO production.Incubation of the endothelial cells with puerarin for 1 h and then treatment of the cells with ox-LDL decreased the TF expression at mRNA and protein levels,increased Akt protein phosphorylation and intracellular NO content.Co-incubation of the endothelial cells with PI3K inhibitor LY294002 and puerarin for 1 h and then treatment of the cells with ox-LDL augmented the TF expression at mRNA and protein levels and the Akt protein dephosphorylation,and decreased NO production.Co-incubation of the endothelial cells with eNOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME) and puerarin significantly decreased the inhibitory effect of puerarin on ox-LDL-induced TF expression at mRNA and protein levels in the endothelial cells,and reduced Akt protein phosphorylation and NO production.CONCLUSION:Puerarin inhibits ox-LDL-induced TF expression at mRNA and protein levels in the human umbilical vein endothelial cells via activation of PI3K/Akt/eNOS signaling pathway.  相似文献   
110.
High-density lipoprotein (HDL) is negatively related to the risk of cardiovascular diseases such as atherosclerosis. Recent studies have shown that HDL activates a variety of target cells, such as vascular endothelial cells and macrophages, and activates the related cell signaling pathway to exert an anti-atherosclerosis role. HDL is a complex substance which composes of multiple particles. The changes of many factors affect the characteristics and functions of HDL, and then affect the activation of endothelial nitric oxide synthase (eNOS).This paper summarizes the recent correlation studies, and expounds the related factors that affect the HDL-eNOS signaling pathway.  相似文献   
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