台风过后网箱养殖大黄鱼恢复过程中血清代谢物变化的研究

为了考察台风影响后鱼类恢复过程中血清代谢物的变化,利用超高效液相色谱-四极杆-飞行时间质谱,电喷雾电离源分别在正负离子模式下,对超强台风"罗莎"影响后的象山港网箱养殖大黄鱼血清进行为期半个月的测定,并通过SIMCA-P软件进行主成分分析和正交偏最小二乘法辨别分析.结果表明,大黄鱼恢复过程中潜在生物标志物主要为磷脂酰胆碱和溶血磷脂酰胆碱.另外还有皮五醇和牛黄胆酸.其中,溶血磷脂酰胆碱、含高不饱和度脂肪酰基的磷脂酰胆碱(总不饱和度之和大于9)和牛黄胆酸在恢复过程中均呈现增加的趋势; 而含低不饱和度脂肪酰基的磷脂酰胆碱(总不饱和度之和小于8)和皮五醇则呈现减少的趋势.这些代谢指标物的变化,体现了大黄鱼在台风后恢复过程中,通过皮质类激素调节脂类物质代谢的结果.     

液相色谱-质谱/质谱法测定包装材料中的全氟辛酸及其盐类物质

全氟辛酸（PFOA）具有中等毒性的肝致癌性,并会影响生物体脂类物质的代谢及抑制生物体的免疫系统功能。本文对包装材料中PFOA及其盐类进行检测,所建立的方法可对包装材料的安全性评价提供技术支撑。     

亲水作用色谱/质谱联用方法用于膀胱癌患者血清代谢组学研究

膀胱癌是泌尿系统最常见的恶性肿瘤之一,具有高发病率、高复发率和高进展率的特点.本研究应用69个极性代谢物标样选择合适的分离系统,建立了两性离子亲水作用色谱/质谱联用的代谢组学分析方法.本方法线性范围较宽,检出限低于ng/mL数量级.将本方法用于血清代谢组学分析,85%以上代谢物峰面积的RSD<30%.对64例膀胱癌患者和32例正常人的血清进行代谢组学研究,发现溶血磷脂酰胆碱、游离脂肪酸、氨基酸、胆汁酸、有机酸、核苷等在患病组和正常组中存在显著差异.经筛选和验证,甘磷酸胆碱、胱氨酸、十二碳烯酸、二十碳烯酸和鹅去氧胆酸5种代谢物可以作为区分膀胱癌和正常人的潜在标志物.本研究结果表明,基于亲水作用色谱/质谱联用的代谢组学方法是发现癌症诊断潜在生物标志物的有效手段.     

基于人工智能技术的烟气暴露大鼠代谢生物标志物筛选方法研究

该研究将主成分分析、偏最小二乘判别分析等多元统计分析方法用于烟草血浆、尿液和肺组织代谢组学数据的分析,以揭示暴露于不同烟气中大鼠血浆、尿液和肺组织中内源性生物标志物的整体变化情况,筛选潜在生物标志物;将血样、尿样和肺组织代谢轮廓谱分析得到的生物标志物进行整合,运用神经模糊网络模型对标志物进行缩减,并用人工神经网络评价模型预测能力,确定烟气暴露不同时间(7,14,30 d)以及不同烟气暴露对大鼠内源性代谢物变化影响"因果效应"密切相关的关键生物标志物群,明确不同烟气对大鼠机体损伤机制的异同。     

全氟辛酸的环境行为及其在多环境介质中的分布

全氟辛酸(PFOA)具有优良的疏水疏油性能及热稳定性,是我国重要的化工产品.但近年来,相关研究已经逐步证实PFOA具有持久性有机污染物的诸多特性,如环境持久性、难降解性及生物蓄积性.动物实验表明低剂量条件下,PFOA就能引发生殖、免疫、心血管和遗传发育等毒性.PFOA等现已成为继二恶英、有机氯农药等有机化合物之后的一种新型持久性有机污染物,是目前全氟化合物中最受关注的种类之一.本文作者针对全氟辛酸的环境行为及其在不同环境介质中的分布及特征做了综述,为将来进一步的研究工作的开展提供借鉴.     

基于肝脏代谢组分析研究低聚硒化氨基多糖对黑鲷的免疫调节作用

采用基于液相色谱-飞行时间质谱联用（LC-TOF-MS）技术的代谢组学方法，分析黑鲷肝脏内源性代谢物的变化，研究硒化氨基多糖增强黑鲷的免疫调节机制。采用XCMS^plus软件非靶向分析质谱采集数据，筛选潜在生物标志物，并通过MetaboAnalyst3.0网站分析相关代谢通路。结果表明，饲喂硒化氨基多糖组中的代谢物明显区分于空白组，发现并鉴定了32个有差异的生物标志物。代谢通路分析结果表明，硒化氨基多糖可通过氨基酰基-转运脱氧核糖核苷酸（tRNA）生物合成、氨基酸代谢、核苷酸代谢、氮代谢等代谢通路增强黑鲷自身的免疫机能。该研究为阐明硒化氨基多糖的免疫增强机制提供了科学依据。     

黄芪口服液降低大鼠顺铂毒性作用机制的尿液代谢组学研究

采用基于液相色谱-飞行时间质谱联用(LC-TOF-MS)技术的代谢组学方法,分析大鼠尿液内源性代谢物的变化,研究黄芪口服液(HO)降低大鼠顺铂(CDDP)毒性的作用机制.采用低剂量多次腹腔注射CDDP的方法建立CDDP染毒大鼠模型,并连续给予16天HO.于第18天收集正常对照(Control)组、顺铂模型(CDDP)组和黄芪口服液(HO)组大鼠的24 h尿液, 进行LC-TOF-MS分析,以获取尿液代谢物组数据集,对所得数据进行主成分分析(PCA)和正交偏最小二乘法-判别分析(OPLS-DA)等多元统计分析,以筛选潜在生物标志物.于第20天采集大鼠血清测定肌酐和尿素氮水平.血清指标测定结果表明, HO可以显著降低CDDP染毒大鼠的肌酐和尿素氮水平(p<0.05).PCA得分图显示,3组可分别聚类,HO组位于Control组和CDDP组中间,表明HO可部分改善CDDP所致大鼠尿液代谢产物的异常变化.综合OPLS-DA分析、t检验和倍数变化分析结果,最终共筛选并初步鉴定出35个尿液代谢产物作为HO减毒相关的潜在生物标记物.代谢通路分析结果表明,HO可通过纠正体内氨基酸代谢、能量代谢和核苷酸代谢等通路的紊乱,降低CDDP所致机体毒性.     

全氟辛酸和全氟辛烷磺酸人体暴露途径解析及其污染控制技术*

全氟辛酸（PFOA）和全氟辛烷磺酸（PFOS）是人工合成全氟化合物的典型代表。近年来,大量的环境调查数据表明它们普遍存在于多种环境介质、生物体甚至人体中,呈现出全球分布的态势,具有环境持久性和生物富集性,对人体健康存在潜在的危害,已成为一类新的环境持久性有机污染物而引起人们广泛的关注。本文介绍了PFOA和PFOS的环境来源和传输途径,解析了人体暴露的三种主要途径以及在食物、饮用水和空气/灰尘中的污染现状,并就围绕着它们所开展的污染控制技术方面的研究进行了评述。在此基础上,通过分析目前研究中所存在的问题,对今后的发展方向和研究重点进行了展望。     

基于液相色谱与质谱联用技术的良性前列腺肥大小鼠血清代谢组学分析

良性前列腺肥大已成为影响老龄男性生活质量的一个常见因素,其发病机制迄今尚未完全阐明。本研究采用超高压液相色谱-四极杆飞行时间串联质谱(UPLC-QTOF-MS)技术检测正常小鼠、良性前列腺肥大和非那雄胺干预的模型小鼠血清中代谢物的变化,对3组小鼠的血清代谢谱进行了分析。采用偏最小二乘-判别分析(PLS-DA)对3组小鼠代谢物分类并寻找潜在生物标志物。数据显示,3组小鼠的血清代谢物谱得到了很好的区分,发现并鉴定了3个潜在生物标志物,分别为1-棕榈酰溶血磷脂酰胆碱、1-O-十六烷基-2-O-乙酰基-SN-甘油基-3-磷酸胆碱和(Z)-13-二十二烯酰胺。结果表明良性前列腺肥大的发生与脂质代谢紊乱密切相关。     

基于超高效液相色谱-质谱的胶质瘤患者血浆代谢组学研究

采用超高效液相色谱-四极杆-静电场轨道阱质谱(UHPLC-Q-OrbitrapHRMS)技术对胶质瘤患者和正常对照人群的血浆进行代谢轮廓分析,筛选胶质瘤代谢标志物,为其发病机制阐明和临床早期诊断提供科学依据。通过对UHPLC-Q-OrbitrapHRMS采集得到的谱图进行峰识别、峰匹配和去噪等处理后,应用主成分和正交偏最小二乘-判别分析法对代谢组学数据进行统计分析,筛选VIP1.0及P0.05的差异代谢物,并进一步对其诊断能力进行评价。结果显示,胶质瘤患者的血浆代谢轮廓发生明显变化,发现并鉴定得到10个差异代谢物,其中亮氨酸、缬氨酸、色氨酸、胆碱和牛磺酸在胶质瘤患者血浆中含量降低,组氨酸、柠檬酸、乳酸、肌酸和丙酮酸含量升高,与正常对照组比较具有显著性差异(P0.05),提示氨基酸和能量等代谢异常可能对胶质瘤的发生发展具有重要影响。此外,各差异性代谢物对胶质瘤均显示出较好的诊断能力(AUC0.8),可作为潜在诊断标志物。     

Nontargeted urine metabolomics analysis of the protective and therapeutic effects of Citri Reticulatae Chachiensis Pericarpium on high-fat feed-induced hyperlipidemia in rats

In this study, we focused on studying the changes in urine metabolites in hyperlipidemic rats using ultra-performance liquid chromatography coupled with quadrupole time-of-fight mass spectrometry (UPLC–Q-TOF/MS) and metabolomics, as well as the effect of Citri Reticulatae Chachiensis Pericarpium (CRCP) on hyperlipidemia. These urine samples were examined by UPLC–Q-TOF/MS to obtain MS data. The MS data were analyzed by principal component analysis and partial least squares-discriminant analysis to identify the differential metabolites. CRCP reduced the body weight and levels of triglycerides, total cholesterol and low-density lipoprotein cholesterol and abnormally decreased high-density lipoprotein cholesterol in hyperlipidemic rats, which were significantly raised by a high-fat diet. Twenty-seven potential biomarkers were identified within the complex sample matrix of urine. Fourteen biomarkers increased in the hyperlipidemia rats compared with normal rats. Meanwhile, 13 biomarkers decreased. CRCP reversed abnormal changes in biomarkers, including 5-l -glutamyl-taurine, 5-aminopentanoic acid, cis-4-octenedioic acid and 2-octenedioic acid. These biomarkers show that hyperlipidemia is related to the metabolic pathways of taurine and hypotaurine metabolism, fatty acid biosynthesis , and arginine and proline metabolism . CRCP mainly prevents hyperlipidemia by intervening in these metabolic pathways.     

气相色谱-质谱和液相色谱-质谱联用方法用于口腔癌代谢组学分析

口腔癌的发病率占全身恶性肿瘤的第6位,正确区分正常状态与良性和恶性口腔肿瘤,是恰当选择治疗方案的关键所在。本研究中,首先利用液相色谱-质谱和气相色谱-质谱联用方法分别得到健康人、良性口腔肿瘤患者和恶性口腔肿瘤患者血浆、尿液和唾液的代谢轮廓,然后应用正交信号校正的偏最小二乘法进行多变量统计分析。结果表明健康人、良性肿瘤患者和恶性肿瘤患者在血浆、尿液和唾液等3种体液代谢中都可以被区分开,而且找到和鉴定出19个重要差异代谢物。相关代谢通路分析显示,与健康人相比,良性和恶性口腔肿瘤患者都存在能量代谢紊乱和脂类代谢失衡的现象,但恶性口腔肿瘤患者还表现出三羧酸循环和肌醇代谢异常,这为临床诊断及治疗提供了重要信息。     

基于气相色谱-飞行时间质谱技术的佐剂性关节炎大鼠尿液代谢组学的研究

采用弗氏完全佐剂(FCA)诱导佐剂性关节炎(AA)大鼠模型,观察大鼠足趾肿胀度和踝关节组织的病理学形态变化。应用气相色谱-飞行时间质谱(GC-TOF MS)技术检测AA大鼠尿液代谢物谱,并对数据进行主成分分析(PCA)、偏最小二乘法-判别分析(PLS-DA)及正交偏最小二乘法-判别分析(OPLS-DA),探讨可能的发病机制。通过变量重要性投影值(VIP>1)和P值(<0.05),筛选出尿液中的差异代谢物。在模型组大鼠的尿液中共发现异柠檬酸、α-酮戊二酸、柠康酸、肌酸、3-羟基丁酸等20种差异代谢物。推断AA代谢组学的发病机制可能与能量代谢、氨基酸代谢、脂肪酸代谢途径有关。     

Metabolomic profiling reveals a role for CPT1c in neuronal oxidative metabolism

Background

Carnitine Palmitoyltransferase-1c (CPT1c) is a neuron specific homologue of the carnitine acyltransferase family of enzymes. CPT1 isoenzymes transfer long chain acyl groups to carnitine. This constitutes a rate setting step for mitochondrial fatty acid beta-oxidation by facilitating the initial step in acyl transfer to the mitochondrial matrix. In general, neurons do not heavily utilize fatty acids for bioenergetic needs and definitive enzymatic activity has been unable to be demonstrated for CPT1c. Although there are studies suggesting an enzymatic role of CPT1c, its role in neurochemistry remains elusive.

Results

In order to better understand how CPT1c functions in neural metabolism, we performed unbiased metabolomic profiling on wild-type (WT) and CPT1c knockout (KO) mouse brains. Consistent with the notion that CPT1c is not involved in fatty acid beta-oxidation, there were no changes in metabolites associated with fatty acid oxidation. Endocannabinoids were suppressed in the CPT1c KO, which may explain the suppression of food intake seen in CPT1c KO mice. Although products of beta-oxidation were unchanged, small changes in carnitine and carnitine metabolites were observed. Finally, we observed changes in redox homeostasis including a greater than 2-fold increase in oxidized glutathione. This indicates that CPT1c may play a role in neural oxidative metabolism.

Conclusions

Steady-state metabolomic analysis of CPT1c WT and KO mouse brains identified a small number of metabolites that differed between CPT1c WT and KO mice. The subtle changes in a broad range of metabolites in vivo indicate that CPT1c does not play a significant or required role in fatty acid oxidation; however, it could play an alternative role in neuronal oxidative metabolism.

     

Quantification of plasma carnitine and acylcarnitines by high-performance liquid chromatography-tandem mass spectrometry using online solid-phase extraction

Carnitine is an amino acid derivative that plays a key role in energy metabolism. Endogenous carnitine is found in its free form or esterified with acyl groups of several chain lengths. Quantification of carnitine and acylcarnitines is of particular interest for screening for research and metabolic disorders. We developed a method with online solid-phase extraction coupled to high-performance liquid chromatography and tandem mass spectrometry to quantify carnitine and three acylcarnitines with different polarity (acetylcarnitine, octanoylcarnitine, and palmitoylcarnitine). Plasma samples were deproteinized with methanol, loaded on a cation exchange trapping column and separated on a reversed-phase C8 column using heptafluorobutyric acid as an ion-pairing reagent. Considering the endogenous nature of the analytes, we quantified with the standard addition method and with external deuterated standards. Solid-phase extraction and separation were achieved within 8 min. Recoveries of carnitine and acylcarnitines were between 98 and 105 %. Both quantification methods were equally accurate (all values within 84 to 116 % of target concentrations) and precise (day-to-day variation of less than 18 %) for all carnitine species and concentrations analyzed. The method was used successfully for determination of carnitine and acylcarnitines in different human samples. In conclusion, we present a method for simultaneous quantification of carnitine and acylcarnitines with a rapid sample work-up. This approach requires small sample volumes and a short analysis time, and it can be applied for the determination of other acylcarnitines than the acylcarnitines tested. The method is useful for applications in research and clinical routine.

Chemical knockout of pantothenate kinase reveals the metabolic and genetic program responsible for hepatic coenzyme A homeostasis

Coenzyme A (CoA) is the major acyl group carrier in intermediary metabolism. Hopantenate (HoPan), a competitive inhibitor of the pantothenate kinases, was used to chemically antagonize CoA biosynthesis. HoPan dramatically reduced liver CoA and mice developed severe hypoglycemia. Insulin was reduced, glucagon and corticosterone were elevated, and fasting accelerated hypoglycemia. Metabolic profiling revealed a large increase in acylcarnitines, illustrating the role of carnitine in buffering acyl groups to maintain the nonesterified CoASH level. HoPan triggered significant changes in hepatic gene expression that substantially increased the thioesterases, which liberate CoASH from acyl-CoA, and increased pyruvate dehydrogenase kinase 1, which prevents the conversion of CoASH to acetyl-CoA. These results identify the metabolic rearrangements that maintain the CoASH pool which is critical to mitochondrial functions, including gluconeogenesis, fatty acid oxidation, and the tricarboxylic acid and urea cycles.     

Urinary metabolomic study of non‐small cell lung carcinoma based on ultra high performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry

Metabolic profiles from human urine reveal the significant difference of carnitine and acylcarnitines levels between non‐small cell lung carcinoma patients and healthy controls. Urine samples from cancer patients and healthy individuals were assayed in this metabolomic study using ultra high performance liquid chromatography coupled to quadrupole time‐of‐flight mass spectrometry. The data were normalized by the sum of all intensities and creatinine calibration, respectively, before orthogonal partial least squares discriminant analysis. Twenty differential metabolites were identified based on standard compounds or tandem mass spectrometry fragments. Among them, some medium‐/long‐chain acylcarnitines, for example, cis‐3,4‐methylene heptanoylcarnitine, were found to be downregulated while carnitine was upregulated in urine samples from the cancer group compared to the control group. Receiver operating characteristic analysis of the two groups showed that the area under curve for the combination of carnitine and 11 selected acylcarnitines was 0.958. This study suggests that the developed carnitine and acylcarnitines profiling method has the potential to be used for screening non‐small cell lung carcinoma.     

基于超高效液相色谱-四极杆飞行时间质谱联用技术的血瘀模型大鼠血浆代谢组学分析

采用盐酸肾上腺素加冰水浴建立急性血瘀大鼠模型，使用超高效液相色谱-四极杆飞行时间质谱（UPLC-Q-TOF/MS）检测空白对照组与血瘀模型组中血浆代谢物，用主成分分析（PCA）、有监督偏最小二乘法判别分析（PLS-DA）及正交偏最小二乘法判别分析（OPLS-DA）对代谢组学数据进行多维统计分析，筛选潜在生物标志物。与对照组相比，在血瘀模型组大鼠血浆中检测出46个差异代谢物，血瘀模型组中乙酰胆碱、N6，N6，N6-三甲基-L-赖氨酸、胞嘧啶、乙酰肉碱等21个代谢物显著上调，吲哚丙酸、LysoPC（14：0）等25个代谢物显著下调，可能与脂质代谢、半乳糖代谢、亚油酸代谢、不饱和脂肪酸生物合成、糖酵解、花生四烯酸代谢等通路有关。代谢产物可作为血瘀证研究中的重要标记物，该研究结果有助于揭示血瘀证的发病机制，可为临床血瘀疾病的诊断及选用药物治疗提供思路，为后续治疗手段提供参考依据。     

Modified Jiu Wei Qiang Huo decoction improves dysfunctional metabolomics in influenza A pneumonia‐infected mice

In order to study the effective mechanism of a traditional Chinese medicine (TCM), modified Jiu Wei Qiang Huo decoction (MJWQH), against H1N1‐induced pneumonia in mice, we chose a holistic approach. A reverse‐phase liquid chromatography with quadruple time‐of‐flight mass spectrometry (LC‐Q‐TOF‐MS) was developed to determine metabolomic biomarkers in mouse serum for the MJWQH effects. Thirteen biomarkers of H1N1‐induced pneumonia in mice serum were identified, which comprised l ‐valine, lauroylcarnitine, palmitoyl‐l ‐carnitine, l ‐ornithine, uric acid, taurine, O‐succinyl‐l ‐homoserine, l ‐leucine, l ‐phenylalanine, PGF2α, 20‐ethyl‐PGE2, arachidonic acid, and glycerophospho‐N‐arachidonoyl ethanolamine. Among them, metabolites of amino acids, fatty acids and arachidonic acid had the most relevant changes in mice with H1N1‐induced pneumonia. MJWQH effectively improved weight loss, lung index, biomarkers and inflammatory mediators such as prostaglandin E2 and phospholipase A2 in the infected mice. Importantly, MJWQH reversed the elevated biomarkers to the control levels from the infection, which provided a systematic view and a theoretical basis for its prevention or treatment. The results suggest that the protective effect of MJWQH against H1N1‐induced pneumonia is possibly through regulation of pathways for amino acid, fatty acid and arachidonic acid metabolism. They also suggest that the LC‐MS‐based metabolomic strategy is a powerful tool for elucidation of the mechanisms of TCM. Copyright © 2013 John Wiley & Sons, Ltd.