Nerve growth factor protects against palmitic acid- induced injury in retinal ganglion cells

Accumulating evidence supports an important role for nerve growth factor （NGF） in diabetic retinopathy. We hypothesized that NGF has a protective effect on rat retinal ganglion RGC-5 cells injured by palmitic acid （PA）, a metabolic factor implicated in the development of dia- betes and its complications. Our results show that PA exposure caused apoptosis of RGC-5 cells, while NGF protected against PA insult in a concentration-dependent manner. Additionally, NGF significantly attenuated the levels of reactive oxygen species （ROS） and malondialde- hyde （MDA） in RGC-5 cells. Pathway inhibitor tests showed that the protective effect of NGF was completely reversed by LY294002 （PI3K inhibitor）, Akt VIII inhibitor, and PD98059 （ERK1/2 inhibitor）. Western blot analysis revealed that NGF induced the phosphorylation of Akt/FoxO1 and ERK1/2 and reversed the PA-evoked reduction in the levels of these proteins. These results indicate that NGF protects RGC-5 cells against PA-induced injury through anti-oxidation and inhibition of apoptosis by modulation of the PI3K/Akt and ERK1/2 signaling pathways.

Eicosane, pentadecane and palmitic acid: The effects in in vitro wound healing studies

Objective: To examine the wound healing properties of eicosane, pentadecane and palmitic acid by evaluating in term of anti-microbial, anti-inflammatory, proliferation, migration and collagen synthesis. Methods: Anti-microbial activities of Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa were evaluated by carrying out disk diffusion and agar well diffusion methods. Growth rate of tested bacteria was also evaluated for 8 h in conjunction with the sample drugs. Besides, U937 cell lines were used as model study for realtime mRNA genes expression studies of TNF-毩 and IL-12 under the treatment. Proliferation, migration and collagen content synthesis were carried out on human dermal fibroblast. Results: None of the sample drugs possessed significant inhibition of bacteria tested in this study both in disk diffusion and agar well diffusion methods. In contrary, significantly low expressed mRNA gene expression levels of TNF-毩 and IL-12 were found under the treatment of respective drugs. Meanwhile in proliferation, migration and hydroxyproline content analysis, all the sample drugs showed no significant positive stimulation. Conclusions: This study therefore explains that apart from their potential in downregulating pro-inflammatory cytokines, these three compounds which were examined individually may not be good candidates in promoting wound healing.

Cannabidiol (CBD) Prevents Palmitic Acid-Induced Drop in Mitochondrial Membrane Potential

Exposure of macrophages and microglia cells to the saturated palmitic acid (PA) leads to reduction in the mitochondrial membrane potential (), shrinkage of the cells and apoptosis. Here we show that the Cannabis component Cannabidiol (CBD) rescues both macrophages and microglia cells from the detrimental effects of PA. CBD prevents the shrinkage in cell size and the reduction incaused by PA. The protective effect of CBD on the macrophage mitochondria is important for sustaining the macrophage population even under the immunosuppressed conditions caused by this drug. To a similar extent, the antagonistic effect of CBD on PA-mediated microglia cytotoxicity is important for its role in neuroprotection.

Palmitic acid reduces the methylation of the FOXO1 promoter to suppress the development of diffuse large B-cell lymphoma via modulating the miR-429/DNMT3A axis

Diffuse large B-cell lymphoma(DLBCL)is characterized by significant treatment resistance.Palmitic acid(PA)has shown promising antitumor properties.This study aims to elucidate the molecular mechanisms by which PA influences DLBCL progression.We quantified the expression levels of microRNAs(miRNAs),Forkhead box protein O1(FOXO1),and DNA methyltransferase 3A(DNMT3A)in both untreated and PA-treated DLBCL tumors and cell lines.Assessments were made of cell viability,apoptosis,and autophagy-related protein expression following PA administration.Interaction analyses among miR-429,DNMT3A,and FOXO1 were conducted using luciferase reporter assays and methylation-specific(MSP)Polymerase chain reaction(PCR).After transfecting the miR-429 inhibitor,negative control(NC)inhibitor,shRNA against DNMT3A(sh-DNMT3A),shRNA negative control(sh-NC),over-expression vector for DNMT3A(oe-DNMT3A),or overexpression negative control(oe-NC),we evaluated the effects of miR-429 and DNMT3A on cell viability,mortality,and autophagy-related protein expression in PA-treated DLBCL cell lines.The efficacy of PA was also tested in vivo using DLBCL tumor-bearing mouse models.MiR-429 and FOXO1 expression levels were downregulated,whereas DNMT3A was upregulated in DLBCL compared to the control group.PA treatment was associated with enhanced autophagy,mediated by the upregulation of miR-429 and downregulation of DNMT3A.The luciferase reporter assay and MSP confirmed that miR-429 directly inhibits DNMT3A,thereby reducing FOXO1 methylation.Subsequent experiments demonstrated that PA promotes autophagy and inhibits DLBCL progression by upregulating miR-429 and modulating the DNMT3A/FOXO1 axis.In vivo PA signific-antly reduced the growth of xenografted tumors through its regulatory impact on the miR-429/DNMT3A/FOXO1 axis.Palmitic acid may modulate autophagy and inhibit DLBCL progression by targeting the miR-429/DNMT3A/FOXO1 signaling pathway,suggesting a novel therapeutic target for DLBCL management.

鸢尾素缓解棕榈酸对骨髓间充质干细胞的成骨抑制

背景:鸢尾素是肌肉细胞在运动时从跨膜蛋白FNDC5中分离出来的肌因子,具有诱导白色脂肪组织褐变的功能,但是其对脂毒性引起的成骨分化的影响及机制尚不清楚。目的:探究鸢尾素对棕榈酸诱导的骨髓间充质干细胞成骨能力的影响及作用机制。方法:CCK-8检测不同浓度棕榈酸对小鼠骨髓间充质干细胞增殖的影响,以及鸢尾素对棕榈酸存在条件下骨髓间充质干细胞增殖的影响;鸢尾素和棕榈酸预处理24 h后,对小鼠骨髓间充质干细胞成骨诱导分化,在成骨诱导培养第7天进行碱性磷酸酶染色,qRT-PCR检测成骨相关基因的表达,Western blot检测AMPK/BMP2/SMAD信号通路相关蛋白的表达,第21天进行茜素红染色,检测成骨差异。结果与结论:①CCK-8结果提示骨髓间充质干细胞的扩增与棕榈酸的浓度呈反比,但在0.02 mmol/L浓度时,棕榈酸对骨髓间充质干细胞扩增无显著影响,鸢尾素质量浓度在0.1-20μg/L范围内时,不影响骨髓间充质干细胞增殖;②碱性磷酸酶染色及茜素红染色结果显示,棕榈酸抑制骨髓间充质干细胞成骨分化能力,鸢尾素能改善棕榈酸诱导的骨髓间充质干细胞成骨抑制,qRT-PCR结果显示,棕榈酸可以引起成骨相关基因下调,而鸢尾素可以抑制这一趋势;③Western bolt结果显示,相较于单纯棕榈酸干预组,鸢尾素处理后增强了骨髓间充质干细胞中AMPK/BMP2/SMAD信号通路传导。该研究发现了鸢尾素能够改善棕榈酸预处理骨髓间充质干细胞的成骨分化能力并提出了具体的机制可能是由AMPK/BMP/SMAD信号通路介导的。

柚皮苷通过抑制ERK1/2活化和DRP1表达减轻棕榈酸处理后脂肪细胞炎症

目的探讨柚皮苷(Nar)对棕榈酸(PA)处理后成熟脂肪细胞炎症反应的影响及机制。方法3T3-L1前脂肪细胞经成脂化诱导为成熟脂肪细胞后采用不同浓度(0、25、50、100、200μmol·L^(-1))PA处理细胞48 h,CCK-8检测细胞活力,ELISA检测细胞上清IL-6水平,确定后续实验最佳PA浓度。不同浓度(0、12.5、25、50、100μmol·L^(-1))Nar处理成熟脂肪细胞,CCK-8检测细胞活力,确定后续实验最佳Nar浓度。单独PA处理实验分为2组:Ctrl组、PA组;联合Nar处理实验分为4组:Ctrl组、PA组、Nar组、PA+Nar组;western blotting法检测各组p-ERK1/2和DRP1蛋白表达水平。联合线粒体裂变抑制剂Mdivi-1处理实验分为7组:Ctrl组、PA组、Nar组、Mdivi-1组、PA+Nar组、PA+Mdivi-1组、PA+Nar+Mdivi-1组,ELISA和western blotting法分别检测7组细胞上清IL-6水平和p-ERK1/2、DRP1蛋白表达水平。结果后续实验PA和Nar分别选择50和25μmol·L^(-1)。与Ctrl组比较,PA组p-ERK1/2和DRP1表达水平均升高(P<0.001)。与PA组比较,PA+Nar组、PA+Mdivi-1组、PA+Nar+Mdivi-1组IL-6水平、p-ERK1/2和DRP1表达均更低(P<0.05);与PA+Nar组比较,PA+Nar+Mdivi-1组IL-6水平差异无统计学意义(P>0.05),但p-ERK1/2和DRP1表达水平均降低(P<0.05)。结论Nar可减轻PA处理后成熟脂肪细胞的炎症反应,其机制是通过抑制ERK1/2激活和DRP1表达实现的。

棕榈酸诱导斑马鱼脂毒性损伤骨形成抑制模型的建立

目的 建立棕榈酸诱导的斑马鱼脂毒性损伤骨形成抑制模型。方法 将AB品系斑马鱼胚胎分为对照组、棕榈酸组(PA组)和辛伐他汀组(SIM组)。从3 dpf(days post fertilization, dpf)开始,PA组、SIM组给予PA造模。从5 dpf开始,SIM组给予SIM连续给药4 d。9 dpf通过钙黄绿素染色法、尼罗红染色法、甘油三酯及总胆固醇含量测定、q-PCR判断模型是否成功建立。结果 PA显著减少斑马鱼椎骨骨节数目、促进脂质堆积、增加甘油三酯及总胆固醇含量、促进成脂相关基因PPARγ、c/EBPα的表达并抑制成骨相关基因ALP、RUNX2的表达。SIM可以改善PA对斑马鱼的骨形成抑制效应。结论 采用PA给药的方法可成功造成与骨质疏松症(osteoporosis, OP)病理过程相似的脂毒性损伤骨形成抑制模型,该方法简便、灵敏、可控,可用于OP及相关疾病的药物筛选。

固定化脂肪酶ANL-MARE催化酸解合成1-油酸-2-棕榈酸-3-亚油酸甘油三酯

1-油酸-2-棕榈酸-3-亚油酸甘油三酯(OPL)是人乳中主要的脂质组成,为满足婴幼儿配方食品母乳化需求,该试验探究了新型固定化脂肪酶ANL-MARE催化制备OPL的方法。试验成功制备和表征了固定化酶ANLMARE,并以ANL-MARE为生物催化剂,建立了一种用三棕榈酸甘油三酯(PPP)、油酸(OA)和亚油酸(LA)高效酶催化制备富含OPL结构脂的方法。经单因素和响应面试验优化,获得OPL最优合成工艺为:PPP与总脂肪酸的摩尔比1:14.27,OA与LA摩尔比为1:0.76,脂肪酶添加量12.70%,反应温度50℃,反应4 h,此条件下产物中OPL相对含量为47.93%,2位棕榈酸(sn-2 PA)占总棕榈酸(PA)的质量分数(sn-2 PA相对含量)为71.69%。此外,固定化酶ANL-MARE与商业脂肪酶相比,表现出较好的催化合成OPL的活性。综上所述,固定化酶ANL-MARE具有催化制备OPL结构脂的重大潜力,为人乳脂替代脂的高效制备提供了新策略和理论基础。

直接法合成棕榈酰基甲基牛磺酸钠的催化剂筛选和反应动力学

N-酰基氨基酸型表面活性剂具有优良的表面活性、安全性和生物降解性,广泛应用于日化、医药和食品等领域。以棕榈酸和N-甲基牛磺酸钠为原料经直接法合成棕榈酰基甲基牛磺酸钠,对比分析了金属氧化物、金属氯化物和硼酸系催化剂对棕榈酰基甲基牛磺酸钠合成反应的影响,筛选出适宜的催化剂,并进行反应动力学研究。结果表明,2-氯苯硼酸可有效催化棕榈酰基甲基牛磺酸钠的合成反应,当2-氯苯硼酸质量为棕榈酸质量的4%时,棕榈酰基甲基牛磺酸钠的收率达到97.5%,选择性达到98.4%。在棕榈酸过量的情况下,反应活化能为68.0 kJ/mol,指前因子为1.6×10^(10 )h^(−1)。

胃腺癌患者血浆脂肪酸组分变化及其对临床分期的预测效能

目的 比较不同临床分期胃腺癌患者的血浆脂肪酸占比,探讨差异脂肪酸对胃腺癌临床分期的预测效能。方法 选择行开放或微创胃腺癌根治性切除手术并经术后病理证实的胃腺癌患者40例,根据第8版美国癌症联合会(AJCC)的临床病理分期标准分为早期组(Ⅰ、Ⅱ期)21例、中晚期组(Ⅲ、Ⅳ期)19例。两组术前采用气相色谱法检测血浆脂肪酸占比,绘制两组间比较有差异的血浆脂肪酸预测临床分期的ROC曲线,计算曲线下面积(AUC),分析其预测价值。结果 按照长短来分:早期组血浆短链脂肪酸(SCFA)、中链脂肪酸(MCFA)、长链脂肪酸(LCFA)占比分别为0.13%(0.04%, 0.53%)、1.66%(0.16%, 2.41%)、96.93%(92.20%, 99.66%),中晚期组分别为0.49%(0.14%, 0.91%)、1.88%(0.24%, 3.52%)、95.64%(93.72%, 98.51%),两组比较差异均无统计学意义(P均>0.05)。按照结构来分:两组血浆饱和脂肪酸(SFA)、单不饱和脂肪酸(MUFA)、多不饱和脂肪酸(PUFA)及PUFA中的Ω-3多不饱和脂肪酸(Ω-3PUFA)、Ω-6多不饱和脂肪酸(Ω-6PUFA)占比比较差异均无统计学意义(P均>0.05);中晚期组血浆SFA中的棕榈酸(PA,C16:0)占比高于早期组,Ω-3PUFA的α-亚麻酸(ALA,C18:3n3)占比低于早期组(P均<0.05);两组其他血浆脂肪酸占比比较差异均无统计学意义(P均>0.05)。血浆PA、ALA单独及联合预测胃腺癌分期的AUC及95%CI分别为0.697(0.534~0.860)、0.703(0.528~0.878)、0.797(0.657~0.937),敏感度分别为58.0%、66.7%、63.2%,特异度分别为76.0%、84.2%、90.5%。结论 中晚期胃腺癌患者血浆PA占比高于早期患者、ALA占比低于早期患者,二者联合检测有助于术前判断胃腺癌患者的临床分期。

线粒体未折叠蛋白反应在棕榈酸诱导肾小管上皮细胞脂质聚集中的作用

目的探讨线粒体未折叠蛋白反应(mitochondrial unfolded protein reaction,UPR^(mt))对肾小管上皮细胞(human kidney 2,HK-2)脂代谢的影响。方法采用棕榈酸(palmitic acid,PA)诱导HK-2细胞内脂质聚集,分别予siRNA抑制UPR^(mt)或巴多索隆(the 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid,CDDO)增强UPR^(mt)。油红染色观察细胞内脂质聚集情况,线粒体膜电位检测试剂盒(JC-1)测定线粒体膜电位(mitochondrial membrane potential,MMP),Mito-SOX测定线粒体内活性氧(reactive oxygen species,ROS)含量,Western blotting检测HSP60、LONP1、CLPP、ACOX1、PPARα、PGC1α、CPT1α蛋白表达。结果PA诱导HK-2细胞脂质聚集、MMP降低、ROS产生增多及UPR^(mt)关键蛋白HSP60、LONP1表达降低;抑制UPR^(mt)可加剧PA导致的脂质聚集、MMP降低、ROS产生增多,HSP60、LONP1表达进一步降低;增强UPR^(mt)可缓解PA导致的脂质聚集、MMP降低、ROS产生增多以及HSP60、LONP1表达降低。结论PA诱导的HK-2细胞脂质聚集可能与线粒体功能障碍有关,UPR^(mt)在该过程中对HK-2细胞具有保护作用。

玉女煎对棕榈酸诱导的L细胞损伤的影响

目的:研究玉女煎对棕榈酸(PA)诱导的肠L细胞损伤的影响。方法:(1)将不同浓度(1.5、3和6 g/L)玉女煎溶液分别与二苯代苦味肼基自由基(DPPH·)溶液(100 mg/L)混合并避光反应30 min,采用全波长酶标仪检测吸光度的变化,评价玉女煎对DPPH·的清除作用。(2)将小鼠肠内分泌细胞系GLUTag分为空白对照组、PA(400μmol/L)组、PA+玉女煎(1.5 g/L)组、PA+玉女煎(3 g/L)组和PA+玉女煎(6 g/L)组,通过Hoechst 33342细胞核染色实验和MTT实验评价玉女煎对PA诱导的细胞凋亡的影响。(3)将GLUTag细胞分为空白对照组、PA组和PA+玉女煎(6 g/L)组,采用免疫荧光染色检测细胞内胰高血糖素样肽1(GLP-1)表达水平,通过2´,7´-二氯荧光素二乙酸酯(DCFH-DA)荧光探针检测细胞内活性氧(ROS)水平,通过Western blot实验检测超氧化物歧化酶1(SOD1)表达水平。结果:(1)玉女煎在体外可显著清除DPPH·(P<0.01)。(2)与PA组比较,玉女煎能以浓度依赖性方式抑制PA诱导的GLUTag细胞活力降低,在6 g/L时效果最明显(P<0.01)。(3)与PA组比较,6 g/L玉女煎能显著恢复GLUTag细胞的GLP-1(P<0.05)和SOD1表达水平(P<0.01),降低ROS水平(P<0.01)。结论:玉女煎可能通过降低细胞内氧化应激水平抑制PA诱导的GLUTag细胞损伤。

膨胀蛭石基复合相变储热材料的制备及性能研究

文章以癸酸-棕榈酸(CA-PA)二元共晶物作为相变材料,膨胀蛭石(EVM)作为支撑材料,采用真空浸渍法制备癸酸-棕榈酸/膨胀蛭石复合相变储热材料(CA-PA/EVM)。通过FT-IR,DSC,TG,热循环等测试方法对癸酸-棕榈酸/膨胀蛭石复合相变储热材料的化学兼容性、储热性能、热稳定性及可靠性进行系统研究。结果表明:膨胀蛭石通过物理作用吸附癸酸-棕榈酸二元共晶物至其层状孔隙结构,且二者化学兼容性良好;癸酸-棕榈酸/膨胀蛭石复合相变储热材料的融化和凝固相变温度分别23.61,20.41℃,熔化和凝固相变潜热分别为67.22,64.87 J/g;膨胀蛭石中癸酸-棕榈酸的封装量可达52.22%,在工作温度下具有良好的热稳定性;癸酸-棕榈酸/膨胀蛭石复合相变储热材料经过100次热循环后仍保持良好的热可靠性,在建筑节能领域具有广阔的应用前景。

多西他赛注射液在注射液用局部覆聚四氟乙烯膜溴化丁基橡胶塞中棕榈酸及硬脂酸迁移量的测定

目的:建立多西他赛注射液与注射液用局部覆聚四氟乙烯膜溴化丁基橡胶塞相容性研究中棕榈酸及硬脂酸迁移量的气相色谱分析方法。方法:采用DB-FFAP色谱柱,采用程序升温:170℃保持2 min,10℃/min速率升高至240℃,保持11 min,流速:2 ml/min;进样口温度220℃;检测器为FID,温度260℃。结果:棕榈酸甲酯及硬脂酸甲酯分别在0.1959~195.86μg/ml(r=0.9999)、0.1918~191.85μg/ml(r=0.9998)浓度范围内呈良好的线性关系;棕榈酸甲酯及硬脂酸甲酯加样回收率分别为96.66%(RSD为0.42%)和96.53%(RSD为0.45%);棕榈酸甲酯、硬脂酸甲酯的检测限分别为58和98 ng/ml。3批样品5个时间点硬脂酸的迁移量为15.21~26.35μg/ml,棕榈酸的迁移量为12.82~16.26μg/ml。结论:经方法学验证,所建立的方法准确可靠,可用于测定多西他赛注射液在注射液用局部覆聚四氟乙烯膜溴化丁基橡胶塞中棕榈酸和硬脂酸迁移量的测定。

Lipase-Catalyzed Synthesis of Sn-2 Palmitate: A Review

Human milk fat(HMF)is an important source of nutrients and energy for infants.Triacylglycerols(TAGs)account for about 98%of HMF and have a unique molecular structure.HMF is highly enriched in palmitic acid(PA)at the sn-2 position of the glycerol backbone(more than 70%)and in unsaturated fatty acids at the sn-1,3 position.The specific TAG structure in HMF plays a valuable function in infant growth.Sn-2 palmitate(mainly 1,3-dioleoyl-2-palmitoyl-glycerol)is one of the structured TAGs that is commonly supplemented into infant formula in order to enable it to present a similar structure to HMF.In this review,the development of the lipase-catalyzed synthesis of sn-2 palmitate over the last 25 years are summarized,with a focus on reaction schemes in a laboratory setting.Particular attention is also paid to the commercialized sn-1,3 regioselective lipases that are used in structured TAGs synthesis,to general methods of TAG analysis,and to successfully developed sn-2 palmitate products on the market.Prospects for the lipase-catalyzed synthesis of sn-2 palmitate are discussed.

Lipase-catalyzed regioselective synthesis of palmitolyglucose ester in ionic liquids

Candida antarctica lipase B (CAL-B) was used as a catalyst in the synthesis of palmitolyglucose ester in the ionic liquids, 1-butyl-3-methylimidazolium triflu- oromethanesulfonate ([Bmim][TfO]), with glucose as a substrates and palmitic acid vinyl ester as the acyl donor. The effect of substrate ratio, lipase content, and temperature on the activity and stability of lipase was studied. The reaction conditions in [Bmim][TfO] re- sulting in the highest yield of the sugar ester were a temperature of 50?C, enzyme concentration of 50 mg/ mL, and a molar ratio of glucose/vinyl palmitate of 1:3. The major reaction product was purified and char- acterized by FT-IR, HPLC, MS and NMR, as being 6-O-palmitolyglucose ester. The advantages of ionic liquid vs. organic solvent were noted.

C₁₆Saturated Fatty Acid Induced Autophagy in A549 Cells through Topoisomerase I Inhibition

C16 saturated fatty acid (Palmitic acid) is one of the most common dietary fatty acids which played an important role in the cellular biological functions. Palmitic acid (PA) was tested for potential inhibition of DNA topoisomerase I (topo I) and it exhibited inhibitory activity in the nanomolar range. Treatment of lung adenocarcinoma cell line A549 with PA resulted in a decrease in cell viability in a concentration-dependent manner, and PA showed cytotoxicity with an IC50 value of 150 μM. DNA fragmentation assay and caspase activity indicated that PA does not induce apoptotic cell death in A549 cells. Finally, we found that PA was able to cause an increase in autophagic flux in a time-dependent manner, evidenced by the accumulation of LC3 through monodansylcadaverine (MDC) staining. More importantly, inhibition of autophagy by blocking autophagosome formation via the inhibition of type III Phosphatidylinositol 3-kinases (PI-3K), by 3-Methyladenine (3-MA) was able to effectively suppress PA-induced autophagy. We showed that inhibition of autophagy sensitized the cells signal to PA-induced apoptosis, suggesting the pro-survival function of autophagy induced by PA. Taken together, results from this study reveal that PA as a topo I inhibitor induced autophagic cell death in A549 cells.

Dihydroartemisinin ameliorates palmitate-induced apoptosis in cardiomyocytes via regulation on miR-133b/Sirt1 axis

Excessive fat ectopically deposited in the non-adipose tissues is considered as one of the leading causes of myopathy.The aim of this study was to investigate the role of Dihydroartemisinin(DHA)in palmitate(PAL)-incubated H9c2 cells(lipotoxicity-induced cell injury model).Cell viability of PAL-treated cells was determined by MTT assay,and apoptotic regulators were examined by qRT-PCR and western blot analysis,in the absence or in the presence of DHA,respectively.Expression levels of miR-133b and Sirt1 were also evaluated by qRT-PCR and western blotting examination.PAL decreased the viability of H9c2 cells and enhanced the expression of apoptotic genes.DHA reversed the effect of PAL on cell viability and lowed the level of Caspase3 and Bax.It also lowered the expression of miR-133b,while enhanced the expression of Bcl-2.Sirt1 was revealed as target of miR-133b through transcriptional regulation and the process was affected by DHA.DHA partially protected against the PAL-induced lipotoxicity by influencing the expression of miR-133b that hindered the activity of Sirt1.DHA may be used as a potential treatment in clinical management for lipotoxicity induced heart complications.

基于棕榈酸-硬脂酸/膨胀石墨定形复合相变储能材料的制备与表征

以棕榈酸(PA)和硬脂酸(SA)共晶混合物为相变材料(PCM)、膨胀石墨(EG)为支撑材料,采用熔融共混法制备了新型定形PCM,并研究了其微观结构和热性能。复合PCM中PA-SA二元共晶混合物与EG的最佳吸附质量比为8∶1,PA-SA均匀分布在EG孔隙中,PCM在熔融状态下不发生泄漏。实验表明,复合PCM的最佳堆积密度为800 kg/m^(3),且热导率与堆积密度成正比。DSC结果表明,复合PCM具有适宜的相变温度(T m:54.34℃,T f:54.02℃)和较高的潜热(ΔH m:163.19 J/g,ΔH f:161.65 J/g)。蓄放热循环与TGA结果表明,复合PCM在1000次热循环后仍保持优异的热循环稳定性,在低温储能领域有着广阔的应用前景。

人乳替代脂鲳鱼油和巴沙鱼油的脂肪酸、甘油三酯组成及含量分析

为寻找与中国人乳脂脂质组成高相似的天然人乳替代脂,分析比较了3种鱼油(金鲳鱼油、银鲳鱼油和巴沙鱼油)的总脂肪酸、sn-2位脂肪酸、甘油三酯组成和含量。结果表明:金鲳鱼油中棕榈酸、油酸和亚油酸含量分别为24.93%、25.61%和26.52%,其中sn-2位棕榈酸的含量为39.71%,占总棕榈酸比例为53.10%;在3种鱼油中,金鲳鱼油总脂肪酸组成最接近中国人乳脂;甘油三酯组成分析结果证实,金鲳鱼油中富含1-油酸-2-棕榈酸-3-亚油酸甘油三酯(OPL,24.36%),其含量显著高于其他两种鱼油,且其1,3-二油酸-2-棕榈酸甘油三酯(OPO)的含量(16.79%)接近报道的中国人乳脂的平均含量(15.84%)。因此,金鲳鱼油是理想的中国婴儿配方奶粉专用油脂基料油,在人乳替代脂中具有良好的发展前景。