Serum metabolomics study of patients with allergic rhinitis

Allergic rhinitis (AR) negatively affects the healthy lives of many individuals. Most previous studies on AR focused on the expression of cytokines, with only a few analyzing cytokine expression from a metabolomics viewpoint. Therefore, it is worthwhile to study AR at the metabolic level. Consequently, we aimed to identify differential serum biomarkers by metabolomics. In this study, the orthogonal partial least squares discriminant analysis (OPLS-DA) model was applied to characterize the differences in serum samples collected from patients with AR and healthy volunteers. Ten metabolites (except hexadecanoic acid) were found to be altered significantly (p < .05) in the former group, according to results of principal component analysis and OPLS-DA, indicating that these metabolites could be potential biomarkers. MetaboAnalyst 4.0 and pathway enrichment analysis showed that these changes in metabolites mainly involved three pathways, namely, porphyrin and chlorophyll metabolism, arachidonic acid metabolism, and purine metabolism. Our findings may contribute to a better understanding of the potential pathogenesis mechanisms and provide a metabolic evidence for in-depth studies of AR.     

Metabolomics approach based on utra-performance liquid chromatography coupled to mass spectrometry with chemometrics methods for high-throughput analysis of metabolite biomarkers to explore the abnormal metabolic pathways associated with myocardial dysfunction

Ultra-performance liquid chromatography/mass spectrometry-based metabolomics can been used for discovery of metabolite biomarkers to explore the metabolic pathway of diseases. Identification of metabolic pathways is key to understanding the pathogenesis and mechanism of disease. Myocardial dysfunction induced by sepsis (SMD) is a severe complication of septic shock and represents major causes of death in intensive care units; however its pathological mechanism is still not clear. In this study, ultrahigh-pressure liquid chromatography with mass spectrometry-based metabolomics with chemometrics anaylsis and multivariate pattern recognition analysis were used to detect urinary metabolic profile changes in a lipopolysaccharide-induced SMD mouse model. Multivariate statistical analysis including principal component analysis and orthogonapartial least squares discriminant analysis for the discrimination of SMD was conducted to identify potential biomarkers. A total of 19 differential metabolites were discovered by high-resolution mass spectrometry-based urinary metabolomics strategy. The altered biochemical pathways based on these metabolites showed that tyrosine metabolism, phenylalanine metabolism, ubiquinone biosynthesis and vitamin B6 metabolism were closely connected to the pathological processes of SMD. Consequently, integrated chemometric analyses of these metabolic pathways are necessary to extract information for the discovery of novel insights into the pathogenesis of disease.     

基于超高效液相色谱-高分辨质谱联用技术的桑黄干预后大鼠尿液代谢组学分析

为探讨服用桑黄水煎液对机体的影响,采用超高效液相色谱-高分辨质谱（UPLC-HDMS）联用技术,检测灌胃给予桑黄水煎液后大鼠尿液中代谢物的变化。采用正交偏最小二乘法判别分析（OPLS-DA）对空白组和给药组大鼠尿液代谢物进行聚类分析,筛选出潜在的生物标志物,并通过MetaboAnalyst 3.0网站分析相关代谢通路。数据显示,两组大鼠尿液中的代谢物在第28天得到了很好的区分,发现并鉴定了10个生物标记物。灌胃给予桑黄水煎液主要对机体的半胱氨酸和甲硫氨酸代谢、精氨酸和脯氨酸代谢、嘌呤代谢等代谢通路产生影响。研究结果为深入探讨桑黄药效作用机制奠定了一定的实验基础。     

Urinary biomarker and treatment mechanism of Rhizoma Alismatis on hyperlipidemia

Rhizoma Alismatis (RA), a diuretic in Asia and Europe, was found to possess anti‐hyperlipidemic activity. Since the biomarkers and mechanisms of RA in the treatment of hyperlipidemia are inadequate, ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight synapt high‐definition mass spectrometry and multivariate data analysis were employed to investigate the urinary metabolomics of RA on hyperlipidemic rats induced by high‐fat diet. The metabolic profile of RA‐treated hyperlipidemic group located between control and diet‐induced hyperlipidemic groups. Nineteen metabolites with significant fluctuations were identified as potential biomarkers related to the hyperlipidemia and anti‐hyperlipidemia of RA using partial least‐squares‐discriminate analysis, heatmap analysis and correlation coefficient analysis. The fluctuations of these biomarkers represented disturbances in amino acid metabolism, purine metabolism, pyrimidine metabolism and energy metabolism. After RA treatment, these perturbed metabolites were restored to normal or nearly normal levels. RA can alleviate high‐fat diet‐induced dysfunctions in these metabolic pathways.     

Urinary metabolomic study of systemic lupus erythematosus based on gas chromatography/mass spectrometry

Systemic lupus erythematosus (SLE) is an autoimmune disease with heterogeneous organ and system manifestations. In this study, urinary metabolic alterations related to SLE were investigated by performing gas chromatography/mass spectrometry (GC/MS) based metabolomics and multivariate statistical analysis. Patients with SLE and healthy controls could be clearly differentiated in view of the metabolic abnormity in urine. Among 70 identified endogenous metabolites, 23 metabolites were dramatically increased in SLE patients, which involved in several key metabolic pathways including energy metabolism, nucleotide metabolism, oxidative stress and gut‐microbiome‐derived metabolism. This noninvasive and GC/MS‐based metabolomic technique is a promising and potent strategy for identifying novel biomarkers and understanding pathogenesis of SLE. Copyright © 2016 John Wiley & Sons, Ltd.     

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。     

Metabolic profiling of serum in patients with cartilage tumours using 1H-NMR spectroscopy: A pilot study

Cartilage-forming lesions include tumours that can vary in severity from benign enchondromas to high-grade malignant chondrosarcomas. Chondrosarcoma is the second most frequent malignant bone tumour, accounting for 20–30% of all malignant bone neoplasms. Surgery is the standard treatment for cartilage tumours (CTs); however, their incidental diagnosis and the difficult differentiation of low-grade lesions like chondrosarcoma grade I from benign entities like enchondroma are challenges for clinical management. In this sense, the search for circulating biomarkers for early detection and prognosis is an ongoing interest. Targeted metabolomics is a powerful tool that can propose potential biomarkers in biological fluids as well as help to discover disturbed metabolic pathways to reveal tumour pathogenesis. In this context, the aim of this study was to investigate the ¹H nuclear magnetic resonance metabolomic serum profile of patients with CTs contrasted with healthy controls. Forty-one metabolites were identified and quantified; the multivariate statistical methods principal component analysis and partial least squares discriminant analysis reveal a clear separation of the CT group, that is, the differential metabolites that were involved in two main metabolic pathways: the taurine and hypotaurine metabolism and synthesis and degradation of ketone bodies. Our results represent preliminary work for emergent serum-based diagnostics or prognostic methods for patients with chondrogenic tumours.     

Metabonomics analysis of semen euphorbiae and semen Euphorbiae Pulveratum using UPLC–Q-TOF/MS

Semen Euphorbiae (SE), the dry and mature seed of Euphorbia lathyris L., a common traditional Chinese medicine, has significant pharmacological activity. However, its toxicity limits its clinical application, and less toxic Semen Euphorbiae Pulveratum (SEP) is often used clinically. To explore the possible mechanism of SE frost-making and attenuation, this study used ultrahigh-performance liquid chromatography coupled with quadrupole time of flight mass spectrometry to perform a comprehensive metabolomics analysis of serum and urine samples from rats treated with SE and SEP, and performed histopathological evaluation of liver, kidney and colon tissues. Meanwhile, the different metabolites were visualized through multivariate statistical analysis and the HMDB and KEGG databases were used to distinguish the differential metabolites of SE and SEP to reveal related metabolic pathways and their significance. In total, 32 potential biomarkers, 14 in serum and 18 in urine, were identified. The metabolic pathway analysis revealed that arachidonic acid metabolism, sphingolipid metabolism, tyrosine and tryptophan biosynthesis, the tricarboxylic acid cycle and seven other metabolic pathways were significantly altered. Importantly, compared with SE, SEP reduced the metabolic disorder related to endogenous components. The mechanism may be related to the regulation of lipid metabolism, intestinal flora metabolites, amino acid metabolism and energy metabolism. This study provided new insights into the possible mechanism of SE freezing and attenuation.     

LC Coupled with TOFMS for Metabonomics Study of Mini-pigs with Atherosclerosis

In this study, serum metabolic profiles of mini-pigs with atherosclerosis (AS) were analyzed by LC–TOFMS. Partial least-squares to latent structure-discriminant analysis and orthogonal projection to latent structure-discriminant analysis were used for group differentiation and selection of potential biomarkers. The mini-pig disease models were constructed by feeding a high-fat diet and inducing coronary injury, in accordance with the mechanism of AS pathogenesis. To characterize the development of AS, serum samples were collected and analyzed at two time points (two and ten weeks). Separate distinct clustering of results from normal and model mini-pigs could be observed for both the two and ten-week samples. With the development of AS, the metabolism of the model mini-pigs was more substantially disturbed. Major metabolites contributing to the discrimination were fatty acids, lysophosphatidylcholines, and bile acids. These potential biomarkers are related with inflammation, oxidative stress, and abnormal lipid and energy metabolism.

     

Metabonomics Study of Heart Homogenates from Myocardial Infarction Rats Using Liquid Chromatography/Time of Flight Mass Spectrometry

In this study, a metabonomics analysis of heart homogenates from myocardial ischemic rats was performed by LC–TOF–MS. Hydrophilic interaction chromatography (HILIC) was used to separate the endogenous metabolites in heart homogenates. Partial least squares to latent structure-discriminant analysis (PLS-DA) was used for data analysis. Good separations were observed between the normal and model groups and 15 potential biomarkers were identified. The major disturbed metabolic pathways were purine metabolism, pyrimidine metabolism, urea cycle, and energy metabolism. The results demonstrated that a metabonomics approach based on HILIC-MS was useful for studying metabolic mechanism on target tissue of the myocardial infarction rat.

     

Serum metabolomic profiling in patients with Alzheimer disease and amnestic mild cognitive impairment by GC/MS

The aim of this study was to characterize the serum metabolic profiles of patients with Alzheimer’s disease (AD) and amnestic mild cognitive impairment (AMCI) using metabolomics based on gas chromatography–mass spectrometry (GC/MS). Serum samples were collected from patients with AD (n = 30) and AMCI (n = 32), and normal healthy controls (NOR, n = 40). Metabolite profiles were performed with GC/MS in conjunction with multivariate statistical analysis, and possible biomarker metabolites were identified. Thirty-one kinds of endogenous metabolites could be identified simultaneously. Eleven components were chosen as biomarker metabolites between AD and NOR groups, and these metabolites were closely related to seven biological pathways: arginine and proline metabolism, phenylalanine metabolism, β-alanine metabolism, primary bile acid synthesis, glutathione metabolism, starch and sucrose metabolism, and steroid hormone biosynthesis. Meanwhile, 10 components were chosen as biomarker metabolites between AMCI and NOR groups and seven biological pathways were closely related: arginine and proline metabolism, phenylalanine metabolism, citrate cycle, alanine, aspartate and glutamate metabolism, taurine and hypotaurine metabolism, starch and sucrose metabolism, and steroid hormone biosynthesis. Our study distinguished serum metabotypes between AD, AMCI and NOR patients successfully. The implementation of this metabolomic strategy may help to develop biochemical insight into the metabolic alterations in AD/AMCI and will be helpful for the further understanding of pathogenesis.     

High-throughput lipidomics analysis to discover lipid biomarkers and profiles as potential targets for evaluating efficacy of Kai-Xin-San against APP/PS1 transgenic mice based on UPLC–Q/TOF–MS

Lipid metabolism has a significant function in the central nervous system and Alzheimer's disease (AD) is an age-related senile disease characterized by central nerve degeneration. The pathological development of AD is closely related to lipid metabolism disorders. To reveal the influence of Kai-Xin-San (KXS) on lipid metabolism in APP/PSI transgenic mice and potential therapeutic targets for treating AD, brain tissue samples were collected and analyzed by high-throughput lipidomics based on UPLC–Q/TOF-MS. The collected raw data were processed by multivariate data analysis to discover the potential biomarkers and lipid metabolic profiles. Compared with the control wild-type mouse group, nine potential lipid biomarkers were found in the AD model group, of which seven were up-regulated and two were down-regulated. Orally administrated KXS can reverse the changes in these potential biomarkers. Compared with the model group, a total of six differential metabolites showed a recovery trend and may be potential targets for KXS to treat AD. This study showed that high-throughput lipidomics can be used to discover the perturbed pathways and lipid biomarkers as potential targets to reveal the therapeutic effects of KXS.     

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.     

Metabolomic profiles delineate the effect of Sanmiao wan on hyperuricemia in rats

A serum metabolomic method based on ultra‐high‐performance liquid chromatography coupled with mass spectrometry was developed to characterize hyperuricemia‐related metabolic profiles and delineate the mechanism of Sanmiao wan (SMW), a traditional Chinese medicine (TCM), in treating hyperuricemic rats. With partial least‐squares discriminant analysis for classification and selection of biomarkers, 13 potential biomarkers in mouse serum were identified in the screen, primarily involved in purine metabolism, arginine and proline metabolism, citrate cycle, phenylalanine metabolism, tryptophan metabolism and glycerophospholipid metabolism. Taking these potential biomarkers as screening indexes, SMW could reverse the pathological process of hyperuricemia through partially regulating the perturbed metabolic pathway except for glycerophospholipid metabolism. Our results showed that a metabolomic approach offers a useful tool to identify hyperuricemia‐related biomarkers and provides a new methodological cue for systematically dissecting the underlying efficacies and mechanisms of TCM in treating hyperuricemia.     

Exploratory urinary metabolic biomarkers and pathways using UPLC-Q-TOF-HDMS coupled with pattern recognition approach

Metabolomics represents an emerging and powerful discipline concerned with the comprehensive analysis of small molecules and provides a powerful approach to discover biomarkers in biological systems. Recent development of biomarkers for diagnosis and therapeutic monitoring of liver-stagnation and spleen-deficiency syndrome (LSS)-type disease remains challenging. This study was undertaken to discover novel potential biomarkers for the non-invasive early diagnosis of human LSS. Urine samples which are potentially a rich source of metabolites were collected from patients with LSS, together with healthy control samples. Metabolite profiling was performed by ultra-performance liquid-chromatography/electrospray-ionization synapt high-definition mass spectrometry (UPLC-Q-TOF-HDMS) in conjunction with multivariate data analysis and ingenuity pathway analysis that were used to select the metabolites to be used for the non-invasive diagnosis of LSS. Twelve urinary differential metabolites contributing to the complete separation of LSS patients from matched healthy controls were identified involving several key metabolic pathways such as pentose and glucuronate interconversions, ascorbate, aldarate, cysteine, methionine, tyrosine, tryptophan, amino sugar and nucleotide sugar metabolism. More importantly, of the 12 differential metabolites, 4 metabolite markers, prolylhydroxyproline, l-homocystine, 2-octenoylcarnitine and α-N-phenylacetyl-l-glutamine, were effective for the diagnosis of human LSS, with an achieved sensitivity of 93.0%. These results demonstrate that robust metabolomics has the potential as a non-invasive strategy and promising screening tool to evaluate the potential of these metabolites in the early diagnosis of LSS patients and provides new insight into pathophysiological mechanisms.     

Identification of the constituents and metabolites in rats after oral administration of Zi Shen Formula by UPLC‐Q‐TOF/MS combined pattern recognition analysis

An ultra‐high‐performance liquid chromatography mass spectrometry method was established to detect and identify the chemical constituents of Zi Shen Formula (ZSF) and its metabolites in serum, urine and feces, after oral administration to rats. A total of 68 compounds were characterized in ZSF extracts. In vivo, 38 prototype components and 32 metabolites of ZSF were tentatively identified in rat serum, urine and feces. Seven metabolic pathways including demethylation, hydroxylation, oxidation, sulfation, glucuronidation, methylation and de‐caffeoyl were proposed to be involved in the generation of these metabolites. It was found that glucuronidation, methylation and demethylation were the major metabolic processes of alkaloids, while demethylation, methylation, sulfation and de‐caffeoyl were the major metabolic pathways of phenylethanoid glycosides. The main metabolic pathways of steroidal saponins were oxidation and isotype reactions. These findings are significant for our understanding of the metabolism of ZSF. The proposed metabolic pathways of bioactive components might be crucial for further studies of the mechanisms of action and pharmacokinetic evaluations of ZSF.     

Metabolomic Characterization of Cerebrospinal Fluid from Intracranial Bacterial Infection Pediatric Patients: A Pilot Study

Intracranial bacterial infection remains a major cause of morbidity and mortality in neurosurgical cases. Metabolomic profiling of cerebrospinal fluid (CSF) holds great promise to gain insights into the pathogenesis of central neural system (CNS) bacterial infections. In this pilot study, we analyzed the metabolites in CSF of CNS infection patients and controls in a pseudo-targeted manner, aiming at elucidating the metabolic dysregulation in response to postoperative intracranial bacterial infection of pediatric cases. Untargeted analysis uncovered 597 metabolites, and screened out 206 differential metabolites in case of infection. Targeted verification and pathway analysis filtered out the glycolysis, amino acids metabolism and purine metabolism pathways as potential pathological pathways. These perturbed pathways are involved in the infection-induced oxidative stress and immune response. Characterization of the infection-induced metabolic changes can provide robust biomarkers of CNS bacterial infection for clinical diagnosis, novel pathways for pathological investigation, and new targets for treatment.     

Serum metabolomics using ultra-high performance liquid chromatography–Q-Exactive tandem mass spectrometry reveals the mechanism of action of exercise training on chronic obstructive pulmonary disease rats

Exercise training is the cornerstone component of pulmonary rehabilitation, which results in symptom-reducing, psychosocial, and health economic benefits for chronic obstructive pulmonary disease (COPD) patients. However, the potential mechanisms of its action are poorly understood. This study conducted serum metabolomics using ultra-high performance liquid chromatography–Q-Exactive tandem mass spectrometry to determine the metabolic changes in COPD rats, and the effects of exercise training on improvement in COPD were further investigated. Twelve differential metabolites—which are primarily related to tryptophan metabolism, sphingolipid metabolism, glycerophospholipid metabolism, riboflavin metabolism, pantothenate and CoA biosynthesis, and lysine degradation—were identified in relation to COPD. After the intervention of exercise training, the levels of most metabolites were restored, and the changes in five metabolites were statistically significant, which suggested that exercise training provided effective protection against COPD and might play its role by rebalancing disordered metabolism pathways. This work enhanced our comprehension of the protective mechanism of exercise training on COPD.     

基于快速高分辨液相色谱-质谱的中波紫外线辐射诱导大鼠急性光损伤的代谢组学研究

利用快速高分辨液相色谱-四极杆-飞行时间质谱( RRLC-Q-TOF-MS)联用技术结合多元统计分析方法,考察在中波紫外线( Ultraviolet B, UVB)辐射前后,大鼠尿液中内源性代谢物谱的变化,研究UVB辐射导致急性光损伤的生理机制。急性光损伤大鼠模型由窄谱中波紫外线光源(TL-01,峰值312 nm)照射,采用离心沉降后四倍稀释法处理尿液样本, Supelco Ascentis? Express C18色谱柱,水(含0.1％甲酸)与乙腈为流动相梯度洗脱,液相色谱-串联质谱分析测定。利用主成分分析( PCA)法、聚类分析( CA)法等对辐射前后的大鼠尿液样本进行代谢轮廓分析,寻找对分组贡献大的差异代谢物及通路,并阐明其作用机制;运用偏最小二乘判别分析( PLS-DA)法建立预测模型,考察此模型在UVB致光损伤模型诊断上的预测能力。多元统计分析结果显示,空白对照组与UVB模型组能够获得很好地区分,通过将差异代谢物与数据库、串联质谱数据及标准品比对,发现并鉴定出11种潜在生物标记物,表明UVB辐射可影响正常大鼠的鞘脂类代谢、核酸代谢、亚油酸代谢、氨基酸代谢等通路,这些差异代谢物对UVB辐射致光损伤类疾病的诊断具有较好的预判能力。