Metabolomic Fingerprinting of Three Strains of Rat using Ultra High Resolution Time-of-Flight Mass Spectrometry - Qualitative and Semiquantitative Comparison of Fat, Diabetic and Control Zucker Rats

摘要

Metabolomic profiling in normal and diseased animals is a challenging and rapidly growing area of research. The objective, providing potential dynamic markers of disease states, is at the interface of medicine and pharmacology. Rats represent a common model animal used in studying disease for a variety of reasons, with diabetes and obesity being well-characterized states. UHPLC combined with ultra high-resolution time-of-flight mass spectrometry was utilized in the comparative analysis of metabolomic profiles of serum from three strains of Zucker rats. Specifically, metabolite profiles for lean, fatty, and obese animals are differentially compared and statistically significant features are identified. Accurate mass determination and in source CID were utilized to facilitate analyte identification. Protein removal was accomplished using either simple acetonitrile precipitation or size-based filtration. The samples were analyzed using a global survey at acquisition rates up to 100 spectra/second. The utility of this was evaluated by examining the effect of high-speed separation on metabolite coverage and the number of compounds identified. In addition to analysis by LC/MS, samples were analyzed by GC-TOF-MS using high resolution MS and by GCxGC-TOF. The two GC approaches are compared for coverage and the complementarity of the GC and LC approaches are evaluated. The high-speed acquisition capability facilitates analysis times substantially faster than typically used in serum metabolomics with minimal loss of coverage. The differences in analyte coverage between approaches and analyte levels between disease states are demonstrated. Differences in carbohydrates, small and long chain fatty acids and ketone bodies are observed and compared.