Part II: Latest Advances in Metabolomics Research

In Part I: Recent Advances in Metabolomics Research, we have two advances introduced, "Gut: "Metabnomics" Distinguishes Between Pancreatic Cancer" and "Pancreatitis and Urine Metabolites are Used to Predict the Risk of Diabetes in Individuals".

Progress in the Development of Single-Neuron Identification Of Chemical Constituents, Physiological Changes, And Metabolism Using Mass Spectrometry by Scientists from University of Science and Technology of China

Recently, Proceedings of the National Academy of Sciences of the United States of America (PNAS), the authoritative journal of the National Academy of Sciences published a research paper entitled "Single-Neuron Identification Of Chemical Constituents, Physiological Changes, And Metabolism Using Mass Spectrometry". The study relies on electrophysiological patch clamp and electrospray ion source technology to establish stable single neuron intracellular component sampling and mass spectrometry analysis techniques for mouse hippocampus, prefrontal cortex, amygdala, striatum and other brain regions. Thousands of small chemical molecules in a single neuron were detected by rapid mass spectrometry. Meanwhile, the electrophysiological signals were acquired simultaneously, and the function of neurons, metabolites and metabolic pathways were successfully completed at the single cell level.

This study is the first to use chemical mass spectrometry to directly detect a variety of small neurotransmitters, metabolites, lipids and other small chemical molecules in a single neuron, enabling real-time analysis of individual neuronal chemical components and metabolites. At present, the research on neural cell component analysis has pushed to a living cell and single cell level, and it is expected to study the major problems of life sciences such as neurobiology, metabolomics and toxicology at the single cell level, which is of important application prospects.

Mass spectrometry is gradually being used for single-cell cellular metabolics analysis because of its high sensitivity, large linear range, and high-throughput analytical chemical molecules. However, the current method requires the use of a large amount of organic reagents to treat the cells, and the activity of the cells at the time of sampling cannot be maintained. The lengthy processing and separation process also leads to a slower analysis speed, and it is impossible to complete a large number of single cell analyses in a short time, Ultimately, mass spectrometry analysis of single cell metabolites cannot be used on a large scale for the analysis of nerve cells.

This study successfully established a stable single-cell mass spectrometry technique, and qualitative and quantitative analysis was carried out on glutamine, glutamate and GABA chemical molecules in individual neurons of hippocampus, amygdala and striatum of different age groups, and neuronal classification. Finally, the technique was used to successfully identify the metabolic pathway of glutamine in a single neuron. The maturity and popularity of this method are going to provide a powerful means for subsequent analysis of individual neuron components, neuron classification, and compositional changes in individual neurons under pathological conditions.