Location: Arkansas Children's Nutrition CenterTitle: Synthesis, spectroscopic characterization & detection of cyclopropyl heptanoylcarnitine stereoisomers in human plasma
|SOBHI, HANY - Coppin State University|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 12/17/2019
Publication Date: N/A
Technical Abstract: Acylcarnitine profiles have been used as a biomarker for the clinical diagnoses of metabolic disorder diseases, such as medium and long-chain acyl- CoAdehydrogenase (MCAD, LCAD) deficiency, by using tandem mass spectrometry analyses. Acyltransferace enzymes reversibly interconvert acyl-CoA and acylcarnitine derivatives, thereby facilitating the translocation of the fatty acyl moiety across the mitochondrial membrane. In addition to serving as biomarkers, recent investigations point to bioactivities for some acylcarnitines, including induction of reactive oxygen species, muscle and cardiomyocyte insulin resistance or cell stress. Incomplete fatty acid B-oxidation results in accumulation and increase in acyl carnitine levels in different skeletal muscle tissues and heart. We present the development of a method for the synthesis of less common medium chain acyl carnitine stereoisomers that are hypothesized to originate from long-chain parental fatty acids formed during gut microbe metabolism. We synthesized cis-3,4-methylene-heptanoylcarnitine and its stereoisomer trans-3,4-methylene-heptanoylcarnitine. In the current presentation, the synthesis of these compounds will be presented, based on O-acylation of carnitine chloride, and replacement of the acid chloride by thionyl chloride followed by the addition of carnitine chloride. Furthermore, the spectroscopic characterization of the free fatty acids and the two acylcarnitine steroisimers was achieved using 400 MHz NMR, GC/MS EI-QQQ, and LC/MS QTRAP 5500. Both synthesized steroiomers are purified by solid phase extraction –SPE-, followed by high performance liquid chromatography-HPLC. These new tools will enable further biological characterization of these unique xenolipids in animal models and human clinical studies.