什么是代谢组学？

Metabolism is the assembly of biochemical reactions in living organisms, the material basis for life maintenance of living organisms, and an important basis for the study of life activities.Metabolomics研究内源性的内源性代谢活动在内部和外部环境的影响下，包括对代谢物类型和数量及其变化模式的检测和分析，从而研究了集体生活活动的发生和发展的性质。与其他组织学相比，代谢组学具有多个优点。

• 代谢物的类型和数量的变化易于检测。
• 与基因组学和蛋白质组学相比，技术手段更简单。
• Compared with genomics and of proteomics, the number of metabolites is small and easy to detect, verify and analyze.
• 代谢物水平的变化可以实时揭示生物体的生理病理状态。

Classification of metabolomics

Metabolomics can be divided into untargeted and targeted metabolomics depending on the purpose of the study.

非靶向代谢组学is a comprehensive and systematic analysis of endogenous metabolites in organisms, and is an unbiased metabolomic analysis that can identify new biomarkers.靶向代谢组学专注于对一类代谢产物的研究。

As both metabolomics approaches have their own advantages and disadvantages. Untargeted metabolomics is unbiased and provides a comprehensive and systematic response to the metabolomic profile of living organisms, but is less reproducible and has a limited linear range. Targeted metabolomics, on the other hand, has improved reproducibility and sensitivity, simple metabolite confirmation, and a wide linear range, but requires a prior knowledge background and is a biased metabolomic analysis method. Therefore, in practice, both are often used in combination and work together.

Fig 1. Flowchart for metabolomic studies (Tugizimanaet al。，2013年）。

What are the types of samples that can be tested in metabolomics?

Metabolomics focuses on small molecule metabolites (molecular weight <1000) that serve as substrates and products of various metabolic pathways. The samples analyzed in metabolomics are mainly plasma or serum, urine, saliva, cells, and animal and plant tissues. In addition, plant, fungal and microbial extracts, cerebrospinal fluid, lymphatic fluid, insect hemolymph, amniotic fluid, follicular fluid, knee synovial fluid, tears, semen, placenta, fecal and intestinal contents extracts can also be tested.

代谢组学可以检测到多少物质？

Different mass spectrometry platforms have different sensitivities and biases, and the different platforms are complementary to each other. In general, GC-MS can accurately characterize about 200 substances for serum samples, about 200 substances for urine samples, and several hundred for other samples (e.g. liver, stool, intestinal contents). If comprehensive two-dimensional gas chromatography–mass spectrometry (GC×GC–MS) is used, the number of detectable substances can be more than 1,000. LC-MS can detect far more substances than GC-MS, and depending on the detector (TQ, QTOF, etc.), it may be possible to detect tens to 2-3 hundred substances.

代谢组学的应用

Metabolomics can be used to discover and quantify differentiated metabolites, to delve into and analyze subsequent metabolic molecular markers, and to play an important role in food identification, disease research, animal model validation, biomarker discovery, disease diagnosis, drug development, drug screening,药物评估，临床研究，plant metabolism research， 和microbial metabolism research.

参考

1. Tugizimana, F., Piater, L., & Dubery, I. (2013). Plant metabolomics: A new frontier in phytochemical analysis. South African Journal of Science, 109(5-6), 01-11.