Untargeted Lipidomic Deep-Profiling of Human Plasma via High-Performance Aza-Prilezhaev Aziridination-LC-MS: Unraveling C=C Isomeric Signatures of Charcot-Marie-Tooth Disease

Background Perturbed lipid metabolism in cellular environment plays an essential role in the progression of peripheral neuropathy, such as Charcot-Marie-Tooth disease type 1A (CMT1A). Current deep-profiling of lipidome still has certain limitations for high-throughput analysis of clinical samples, such as low sensitivity, extensive requirement of instrument modification, technician-dependent pretreatment and lack of method-adapted data-processing software. Results Herein, a new generation aza-Prilezhaev aziridination (APA) reagent has been designed for coupling with high-resolution liquid chromatography mass spectrometry (LC-MS) to conduct comprehensive untargeted deep lipidomics of CMT1A disease. It facilitates large-scale lipid structural annotations over a wide polarity range in a single run with high-sensitivity. With the developed method, an extensive library containing information on retention time, m / z , and MS/MS down to C=C location levels for 393 unsaturated lipids of CMT1A was created. Significant disease-related differences in C=C isomer profiles were observed from the comparison of plasma between CMT1A patients (N=9) and controls (N=8). Specifically, 40 different lipids were identified, predominantly comprising n-6, n-7, and n-9 C=C positional isomers. Significance This innovative methodology would offer substantial potential to enhance diagnosis and therapeutic strategies for CMT1A and other diseases based on lipid isomerization information.