Analysis of lipid profile in lipid storage myopathy

Lipid dysmetabolism disease is a condition in which lipids are stored abnormally in organs and tissuesthroughout the body, causing muscle weakness (myopathy). Usually, the diagnosis of this disease and itscharacterization goes through dosage of Acyl CoA in plasma accompanied with evidence of droplets ofintra-fibrils lipids in the patient muscle biopsy. However, to understand the pathophysiological mech-anisms of lipid storage diseases, it is useful to identify the nature of lipids deposited in muscle fiber. Inthis work fatty acids and triglycerides profile of lipid accumulated in the muscle of people suffering frommyopathies syndromes was characterized. In particular, the analyses were carried out on the musclebiopsy of people afflicted by lipid storage myopathy, such as multiple acyl-coenzyme A dehydrogenasedeficiency, and neutral lipid storage disease with myopathy, and by the intramitochondrial lipid storagedysfunctions, such as deficiencies of carnitine palmitoyltransferase II enzyme. A single step extractionand derivatization procedure was applied to analyze fatty acids from muscle tissues by gas chromatog-raphy with a flame ionization detector and with an electronic impact mass spectrometer. Triglycerides,extracted by using n-hexane, were analyzed by high performance liquid chromatography coupled tomass spectrometer equipped with an atmospheric pressure chemical ionization interface. The most rep-resentative fatty acids in all samples were: C16:0 in the 13–24% range, C18:1n9 in the 20–52% range,and C18:2n6 in the 10–25% range. These fatty acids were part of the most representative triglycerides inall samples. The data obtained was statistically elaborated performing a principal component analysis.A satisfactory discrimination was obtained among the different diseases. Using component 1 vs compo-nent 3 a 43.3% of total variance was explained. Such results suggest the important role that lipid profilecharacterization can have in supporting a correct diagnosis.