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11.
Lutein Prevents High Fat Diet‐Induced Atherosclerosis in ApoE‐Deficient Mice by Inhibiting NADPH Oxidase and Increasing PPAR Expression
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Hao Han Wei Cui Linzhi Wang Yufang Xiong Liegang Liu Xiufa Sun Liping Hao 《Lipids》2015,50(3):261-273
Epidemiological and experimental studies provide supportive evidence that lutein, a major carotenoid, may act as a chemopreventive agent against atherosclerosis, although the underlying molecular mechanisms are not well understood. The main aim of this study was to investigate the effects of lutein on the alleviation of atherosclerosis and its molecular mechanisms involved in oxidative stress and lipid metabolism. Male apolipoprotein E knockout mice (n = 55) were fed either a normal chow diet or a high fat diet (HFD) supplemented with or without lutein for 24 weeks. The results showed that a HFD induced atherosclerosis formation, lipid metabolism disorders and oxidative stress, but noticeable improvements were observed in the lutein treated group. Additionally, lutein supplementation reversed the decreased protein expression of aortic heme oxygenase‐1 and increased the mRNA and protein expressions of aortic nicotinamide‐adenine dinucleotide phosphate oxidase stimulated by a HFD. Furthermore, the decreased mRNA and protein expression levels of hepatic peroxisome proliferator‐activated receptor‐α, carnitine palmitoyltransferase 1A, acyl CoA oxidase 1, low density lipoprotein receptors and scavenger receptor class B type I observed in mice with atherosclerosis were markedly enhanced after treatment with lutein. Taken together, these data add new evidence supporting the anti‐atherogenic properties of lutein and describing its mechanisms of action in atherosclerosis prevention, including oxidative stress and lipid metabolism improvements. 相似文献
12.
目的探讨利多卡因防治深二度烧伤创面早期加深的作用。方法wistar大鼠背部深二度烧伤,治疗组局部应用利多卡因凝胶,对照组涂抹安慰剂,检测烧伤后创面组织中Na-K-ATP酶、髓过氧化物酶(MPO)活性和琥珀酸脱氢酶(SDH)、丙二醛(MDA)的含量,HE染色及增殖细胞核抗原(PCNA)免疫组化染色显示创面组织坏死程度。结果对照组和治疗组SDH和Na-K-ATP酶活性在伤后24h均达到最低,之后逐渐升高,但远低于正常水平。伤后24h治疗组SDH、Na-K-ATP活性高于对照组(P<0.05);对照组MPO酶活性在伤后24h达最高,治疗组在伤后48h达最高,之后两组都降低,但仍高于正常水平,对照组MPO活性最高值高于治疗组(P<0.05);对照组和治疗组伤后MDA含量一直升高,伤后72h,对照组高于治疗组(P<0.05)。HE及PCNA染色显示治疗组早期创面进行性损伤明显延缓且较轻,创面组织增殖活力好于对照组。结论深二度烧伤创面早期局部应用利多卡因可减轻创面加深,其机制可能与抑制白细胞浸润、减轻氧化损伤、改善组织活力等因素有关。 相似文献
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14.
V. Coman R. Ludwig W. Harreither D. Haltrich L. Gorton T. Ruzgas S. Shleev 《Fuel Cells》2010,10(1):9-16
We report on the fabrication and characterisation of the very first direct electron transfer‐based glucose/oxygen biofuel cell (BFC) operating in neutral glucose‐containing buffer and human serum. Corynascus thermophilus cellobiose dehydrogenase and Myrothecium verrucaria bilirubin oxidase were used as anodic and cathodic bioelements, respectively. The following characteristics of the mediator‐, separator‐ and membrane‐less, a priori, non‐toxic and simple miniature BFC, was obtained: an open‐circuit voltage of 0.62 and 0.58 V, a maximum power density of ca. 3 and 4 μW cm–2 at 0.37 and 0.19 V of cell voltage, in phosphate buffer and human serum, respectively. 相似文献
15.
Ateek Shah Yashwant Kumar S. Rohan Amrita B. Hazra 《Chembiochem : a European journal of chemical biology》2023,24(11):e202300055
Flavin adenine dinucleotide (FAD) is an essential redox cofactor in cellular metabolism. The organic synthesis of FAD typically involves coupling flavin mononucleotide (FMN) with adenosine monophosphate, however, existing synthesis routes present limitations such as multiple steps, low yields, and/or difficult-to-obtain starting materials. In this study, we report the synthesis of FAD nucleobase analogues with guanine/cytosine/uracil in place of adenine and deoxyadenosine in place of adenosine using chemical and enzymatic approaches with readily available starting materials, achieved in 1–3 steps with moderate yields (10–57 %). We find that the enzymatic route using Methanocaldococcus jannaschii FMN adenylyltransferase (MjFMNAT) is versatile and can produce these FAD analogues in high yields. Further, we demonstrate that Escherichia coli glutathione reductase is capable of binding and using these analogues as cofactors. Finally, we show that FAD nucleobase analogues can be synthesized inside a cell from cellular substrates FMN and nucleoside triphosphates by the heterologous expression of MjFMNAT. This lays the foundation for their use in studying the molecular role of FAD in cellular metabolism and as biorthogonal reagents in biotechnology and synthetic biology. 相似文献
16.
为了提高核糖核酸(RNA)单元应用于棉织物阻燃整理的耐久性以及降低生物阻燃成本,采用烯丙基溴对RNA单元衍生物5'-腺嘌呤核苷酸(AMP)进行改性制备生物阻燃单体。通过紫外光接枝法将AMP单体和AMP单体/丙烯酰胺分别接枝到纯棉织物上,制备了光接枝AMP单体和光接枝AMP单体/丙烯酰胺阻燃棉织物。对阻燃单体化学结构进行了表征。测试了纯棉织物及阻燃棉织物的阻燃性能。研究结果表明:AMP单体中成功引入不饱和双键;2种光接枝阻燃棉织物的分解温度均低于纯棉织物,阻燃棉织物的失重率降低;光接枝AMP单体/丙烯酰胺阻燃棉织物的续燃时间及阴燃时间可降低至0 s,AMP单体与丙烯酰胺之间存在一定的协效阻燃作用且可降低成本。 相似文献
17.
M. Venkateswar Reddy K. AmulyaM.V. Rohit P.N. SarmaS. Venkata Mohan 《International Journal of Hydrogen Energy》2014
Synthesis of bioplastics (polyhydroxyalkanoates (PHA)) using Bacillus tequilensis, a newly isolated strain was investigated under aerobic condition using designed wastewater with synthetic acids (SA) and acidogenic fermented food waste (AFW) collected from biohydrogen (H2) producing anaerobic bioreactors as substrates. The isolate showed the ability to grow and accumulate PHA in both the substrates, with simultaneous waste remediation. Higher PHA synthesis was observed with SA (59% dry cell weight) compared to AFW (36% dry cell weight) with good substrate removal (SA, 87%; AFW, 59%). The PHA composition showed presence of co-polymer [P(3HB-co-3HV)] with varying contents of hydroxy butyrate (HB, 80–90%) and hydroxy valerate (HV, 10–15%) in both the substrates. High dehydrogenase activity was observed which leads to the formation of considerable quantity of PHA. AFW from H2 producing reactor as substrate contributes in reducing the production cost of both H2 as well as PHA embedded with waste valorization. 相似文献
18.
Elettaria cardamomum is one of the most broadly used spices in Moroccan gastronomy. Its antimicrobial activity against both Gram-positive and Gram-negative bacterial species was demonstrated. Likewise, its toxicity was investigated on Swiss albinos mice. Daily, mice were treated orally with 0.003 and 0.3 mg during 7 days. Plasmatic markers and antioxidant defence systems were assessed and histological alterations were evaluated. A significant increase in creatine phosphokinase level was observed. The microscopic evaluation shows that E. cardamomum induce morphological perturbation in mice’s heart. The results show also an inhibitory effect of glyceraldehyde 3-phosphate dehydrogenase and an important increase in the level of thiobarbituric acid reactive substances, succinate dehydrogenase and catalase activities. Results show that E. cardamomum induces toxicity at 0.3 mg/g mouse and affect energy metabolism and oxidative stress. 相似文献
19.
Two anthocyanins (cyanidin-3-O-β-glucoside and peonidin-3-O-β-glucoside) and other phenolic (ferulic acid) were, respectively isolated from black and pigmented brown rices (Oryza sativa L. japonica) and their complete structures were determined by spectroscopic analyses (H NMR, C NMR and MALDI MASS). The HPLC profile of anthocyanins extracted from black rice showed cyanidin-3-O-β-glucoside as the first peak (85%) and peonidin 3-O-β-d-glucoside as the second (15%), while that of pigmented brown rice showed ferulic acid as the first peak (85.7%) and tocols as the second (14.3%). Several tocols were isolated and identified from the unsaponifiable fractions of both rices having some difference on their structures and amounts. The aldose reductase inhibitory activity of isolated compounds was in the following decreasing order: cyanidin-3-glucoside > quercetin > ferulic acid > peonidin-3-glucoside > tocopherol. 相似文献
20.
The optimum conditions for lipids productivity and CO2 fixation of two freshwater strains, namely Chlorella sp. and Pseudochlorococcum sp. and a marine strain; namely Nannochlorpsis sp. have been determined in this work. The species were grown autotrophically under aeration with different CO2 concentrations, ranging from 0.04 to 2% (v/v). The growth was tested in nitrogen sufficient and deficient media at different salinities (0.49–680 mM) and temperatures of 27 and 31 °C. The optimum CO2 enrichment was found to be 1% (v/v) in both media. Nitrogen starvation resulted in an increase in lipid contents, but at lower growth rate, which resulted in a lower overall lipid productivity. The experimental data were used to determine the kinetic parameters of Haldane model. The Chlorella sp. grew well at salinity levels of up to 460 mM. The highest CO2 biofixation rate was observed when Chlorella sp. was grown at 27 °C in seawater (230 mM NaCl).Lipids were extracted from harvested marine strain, Nannochlorpsis sp., and enzymatically transesterified to produce biodiesel in supercritical CO2 (SC–CO2) medium. It was found that the conversion of biodiesel produced from microalgae lipids was 35% higher than that achieved using lamb fat in a similar system. 相似文献