Isolation and purification of monosialotetrahexosylgangliosides from pig brain by extraction and liquid chromatography

Recent advances in the mass spectrometric analysis of glycosphingolipidome - A review

Aberrant expression of glycosphingolipids has been implicated in a myriad of diseases, but our understanding of the strucural diversity, spatial distribution, and biological function of this class of biomolecules remains limited. These challenges partly stem from a lack of sensitive tools that can detect, identify, and quantify glycosphingolipids at the molecular level. Mass spectrometry has emerged as a powerful tool poised to address most of these challenges. Here, we review the recent developments in analytical glycosphingolipidomics with an emphasis on sample preparation, mass spectrometry and tandem mass spectrometry-based structural characterization, label-free and labeling-based quantification. We also discuss the nomenclature of glycosphingolipids, and emerging technologies like ion mobility spectrometry in differentiation of glycosphingolipid isomers. The intrinsic advantages and shortcomings of each method are carefully critiqued in line with an individual's research goals. Finally, future perspectives on analytical sphingolipidomics are stated, including a need for novel and more sensive methods in isomer separation, low abundance species detection, and profiling the spatial distribution of glycosphingolipid molecular species in cells and tissues using imaging mass spectrometry.

Preparation of Ganglioside GM1 by Supercritical CO2 Extraction and Immobilized Sialidase

Monosialotetrahexosylganglioside (GM1) has good activity on brain diseases and was developed to be a drug applied in clinics for neurological disorders and nerve injury. It is difficult to isolate GM1 in industry scale from the brains directly. In this work, a simple and highly efficient method with high yield was developed for the isolation, conversion, and purification of GM1 from a pig brain. Gangliosides (GLS) were first extracted by supercritical CO₂ (SCE). The optimum extraction time of GLS by SCE was 4 h, and the ratio of entrainer to acetone powder from the pig brain was 3:1 (v/w). GM1 was then prepared from GLS by immobilized sialidase and purified by reverse-phase silica gel. Sodium alginate embedding was used for the immobilization of sialidase. Under the optimized method, the yield of high-purity GM1 was around 0.056%. This method has the potential to be applied in the production of GM1 in the industry.

Unbiased Lipidomics and Metabolomics of Human Brain Samples

Mass spectrometry (MS)-based lipidomics and metabolomics approaches have been used to discover new diagnostic and therapeutic targets of neurodegenerative disorders. Here, we describe a protocol to conduct an integrated metabolomics and lipidomics profiling of postmortem brains of frozen tissue samples from clinically characterized patients and age-matched controls. Metabolites and lipids can be extracted from each brain tissue sample, using a biphasic liquid/liquid extraction method. An unbiased liquid chromatography MS-based lipidomics and metabolomics workflows allows to screen for the content and composition of lipids and polar metabolites for each brain tissue. Data processing and statistical analysis are then used to compare the molecular content of all the samples, grouping them into cluster based on molecular similarities. The final results highlight classes of metabolites and biochemical pathways that are altered in brain samples from diseased brains compared to those from healthy subjects, helping to generate novel hypotheses on their mechanistic and functional significance.