Obesity,metabolic health and omics: Current status and future directions

The growing obesity epidemic is becoming a major public health concern, and the associated costs represent a considerable burden on societies. Among the most common complications of severe obesity are the development of hypertension, dyslipidemia, type 2 diabetes, cardiovascular disease, and various types of cancer. Interestingly, some obese individuals have a favorable metabolic profile and appear to be somehow protected from the detrimental effects of excessive adipose tissue accumulation. These individuals remain normoglycemic, insulin sensitive, and hypotensive with proper blood lipid levels, despite their high body mass index and/or waist circumference. Multiple independent observations have led to the concept of the metabolically healthy obese (MHO) phenotype, yet no consensus has been reached to date regarding a universal definition or the main mechanism behind this phenomenon. Recent technological advances and the use of high-throughput analysis techniques have revolutionized different areas of biomedical research. A multi-omics approach, which is used to investigate changes at different molecular levels in an organism or tissue, may provide valuable insights into the interplay between the molecules or pathways and the roles of different factors involved in the mechanisms underlying metabolic health deterioration. The aim of this review is to present the current status regarding the use of omics technologies to investigate the MHO phenotype, as well as the results of targeted analyses conducted in MHO individuals.     

Diagnosing,discarding, or de-VUSsing: A practical guide to (un)targeted metabolomics as variant-transcending functional tests

PurposeFor patients with inherited metabolic disorders (IMDs), any diagnostic delay should be avoided because early initiation of personalized treatment could prevent irreversible health damage. To improve diagnostic interpretation of genetic data, gene function tests can be valuable assets. For IMDs, variant-transcending functional tests are readily available through (un)targeted metabolomics assays. To support the application of metabolomics for this purpose, we developed a gene-based guide to select functional tests to either confirm or exclude an IMD diagnosis.MethodsUsing information from a diagnostic IMD exome panel, Kyoto Encyclopedia of Genes and Genomes, and Inborn Errors of Metabolism Knowledgebase, we compiled a guide for metabolomics-based gene function tests. From our practical experience with this guide, we retrospectively selected illustrative cases for whom combined metabolomic/genomic testing improved diagnostic success and evaluated the effect hereof on clinical management.ResultsThe guide contains 2047 metabolism-associated genes for which a validated or putative variant-transcending gene function test is available. We present 16 patients for whom metabolomic testing either confirmed or ruled out the presence of a second pathogenic variant, validated or ruled out pathogenicity of variants of uncertain significance, or identified a diagnosis initially missed by genetic analysis.ConclusionMetabolomics-based gene function tests provide additional value in the diagnostic trajectory of patients with suspected IMD by enhancing and accelerating diagnostic success.     

刺络联合舒利迭吸入疗法防治小儿哮喘的疗效观察

目的:探讨刺络联合舒利迭吸入疗法治疗小儿哮喘的临床疗效,并观察其用药前后的代谢组学变化。方法:选取2013年10月至2015年9月上海市宝山区中西医结合医院收治的哮喘患儿50例作为研究对象,按照随机数字表法随机分为对照组和观察组,每组25例。对照组采用沙美特罗替卡松粉吸入剂治疗,观察组在对照组治疗的基础上针刺四缝和少商穴位以及耳尖放血,间隔1 d进行1次,周期90 d。采集患儿用药前0 d,用药30 d,用药60 d,用药90 d的尿液,采用气相色谱-质谱联用技术(GC-MS)检测尿液内源性代谢物,观察治疗前后2组患儿临床症状评分、免疫指标以及代谢谱的变化情况。结果:观察组总有效率高于对照组,2组比较差异有统计学意义(P<0.05);与治疗前比较,2组患儿各项中医症候均明显减轻,观察组改善程度比对照组更为显著,差异有统计学意义,2组免疫学指标与治疗前比较均显著降低(P<0.05),与对照组比较(90 d),观察组(90 d)各指标降低程度更为明显,差异均有统计学意义(P<0.05)。采用有监督的分析-OPLS分析了治疗前对照组和观察组(0 d),治疗后(90 d)对照组和观察组的尿液代谢谱,结果显示4组代谢谱分离良好,鉴定了21个相关代谢标志物。结论:刺络联合舒利迭吸入疗法治疗小儿哮喘的临床效果确切,可改善患儿症状,降低免疫指标,其作用机制可能与丙氨酸,天冬氨酸和谷氨酸代谢、乙醛酸和二羧酸代谢和组氨酸代谢等代谢异常有关。     

癌症患者血清代谢组学的HPLC和LC-MS研究

目的 本实验采用HPLC法和LC-MS技术检测了健康人和肿瘤患者人血清样品中的代谢产物,鉴定了与肿瘤生长相关的代谢物,以阐明癌症患者血清代谢组学规律.方法 HPLC条件:色谱柱为Phenomenex Luna(150mm×4.6mm,5μm),流动相为水-75％甲醇(0.1％醋酸铵水溶液);检测波长为215nm,进样量为l0μL;质谱条件为电喷雾离子检测器(ESI)负离子模式下检测;毛细管电压为2.74kV;锥孔电压为25.52V;离子源温度为100℃;得到保留时间和峰面积,数据经SIMCA-P+软件进行正交-偏最小二乘投影判别分析(OPLS-DA),表达出与肿瘤相关的差异代谢物;利用LC-MS对相关代谢物进行鉴定.结果 检测精密度RSD在0.04％～0.61％之间,健康人血清和肿瘤人血清中代谢规律得到明显区分;5种相关代谢组分得到提取和鉴定,分别为苏氨酸,色氨酸,甘油二酯,磷酰胆碱和硬脂酸.结论 肿瘤患者和健康人血清代谢规律有明显差异,鉴定出的化合物与肿瘤生长代谢密切相关,可为肿瘤疾病生物标记物的研究提供相关基础依据.     

代谢组学在妇科常见肿瘤治疗和预后评估中的应用

卵巢癌、子宫内膜癌和宫颈癌是妇科常见的三大恶性肿瘤,尽管随着手术、放化疗等综合治疗的不断发展,妇科常见恶性肿瘤患者的预后得到了大幅提升,但由于早期没有明显症状且缺乏准确诊断或发现时已是晚期,仍有相当比例的患者预后不佳,生命受到严重威胁。因此,寻找新的治疗靶点和监测疗效的有效标志物至关重要。代谢组学（metabonomics）是肿瘤研究领域颇受关注的研究方法,其理论基础是肿瘤存在有别于正常组织的代谢特征,肿瘤独特的代谢特征与生物表型存在紧密的关联。代谢组学通过对生物系统中内源性代谢物进行全面分析,阐明肿瘤在发生和进展过程中某些关键生化途径的重塑机制,并对其进行解析与精准干预。综述代谢组学在妇科常见肿瘤治疗和预后评估中的应用,预期其可为妇科常见肿瘤的个性化、精准化治疗提供潜在靶点,为妇科常见肿瘤筛选预后生物标志物提供重要参考。     

肠道菌群及联用组学技术在中药领域上的研究进展

肠道菌群与各脏器相关联,能够反映中医药整体观特点。肠道菌群在中药作用机制、配伍应用和毒理等领域广泛应用。中药可影响肠道菌群数量和组成,改善肠菌丰度和多样性,同时肠道菌群也可代谢转化中药活性成分,与中药相互影响,促进中药药效发挥。肠道菌群联合代谢组学等多组学技术通过多层次分析,有利于全面阐释肠道菌群与中药作用机制。本文利用数据库综合检索近十年发表的相关文献,阐释肠道菌群和中药之间的相互作用,归纳总结肠道菌群在中药药效、配伍、炮制、毒理领域的研究进展以及与代谢组学等多组学技术联合应用,为深入研究肠道菌群和中药之间的关系及多组学技术在肠道菌群与中药之间的应用提供理论依据和参考。     

Analysis of the metabolic footprint and tissue metabolome of placental villous explants cultured at different oxygen tensions reveals novel redox biomarkers

Pre-eclampsia (PE) is a multi-system disorder of pregnancy hypothesised to arise from circulating factors derived from an unhealthy placenta. Some changes in placental phenotype seen in PE can be reproduced by culture in altered oxygen (O(2)) tension. Currently, these circulating factors are unidentified, partly due to the complexity of maternal plasma. Investigation of factors released from placental tissue provides a potential method to identify bioactive compounds. Experimental strategies to study compounds present in a biological system have expanded greatly in recent years. Metabolomics can detect and identify endogenous and secreted metabolites. We aimed to determine whether metabolites could be identified in placental cultures with acceptable experimental variability and to determine whether altered O(2) tension affects the composition of the placental metabolome. In this study we used gas-chromatography-mass spectroscopy to determine the presence of metabolites in conditioned culture medium (CCM) and tissue lysates of placental villous explants cultured in 1, 6 and 20% atmospheric O(2) for 96h. This experimental strategy had an intra-assay variation of 6.1-11.6%. Intra and inter-placental variability were 15.7-35.8% and 44.8-46.2% respectively. Metabolic differences were identified between samples cultured in 1, 6 and 20% O(2) in both CCM and tissue lysate. Differentially expressed metabolites included: 2-deoxyribose, threitol or erythritol and hexadecanoic acid. We conclude that metabolomic strategies offer a novel approach to investigate placental function. When conducted under carefully controlled conditions, with appropriate statistical analysis, metabolic differences can be identified in placental explants in response to altered O(2) tension. Metabolomics could be used to identify changes in conditions associated with placental pathology.     

Erythrocyte sphingolipid species as biomarkers of Alzheimer's disease

Diagnosing Alzheimer's disease (AD) in the early stage is challenging. Informative biomarkers can be of great value for population-based screening. Metabolomics studies have been used to find potential biomarkers, but commonly used tissue sources can be difficult to obtain. The objective of this study was to determine the potential utility of erythrocyte metabolite profiles in screening for AD. Unlike some commonly-used sources such as cerebrospinal fluid and brain tissue, erythrocytes are plentiful and easily accessed. Moreover, erythrocytes are metabolically active, a feature that distinguishes this sample source from other bodily fluids like plasma and urine. In this preliminary pilot study, the erythrocyte metabolomes of 10 histopathologically confirmed AD patients and 10 patients without AD (control (CTRL)) were compared. Whole blood was collected post-mortem and erythrocytes were analyzed using ultra-performance liquid chromatography tandem mass spectrometry. Over 750 metabolites were identified in AD and CTRL erythrocytes. Seven were increased in AD while 24 were decreased (P<0.05). The majority of the metabolites increased in AD were associated with amino acid metabolism and all of the decreased metabolites were associated with lipid metabolism. Prominent among the potential biomarkers were 10 sphingolipid or sphingolipid-related species that were consistently decreased in AD patients. Sphingolipids have been previously implicated in AD and other neurological conditions. Furthermore, previous studies have shown that erythrocyte sphingolipid concentrations vary widely in normal, healthy adults. Together, these observations suggest that certain erythrocyte lipid phenotypes could be markers of risk for development of AD.