In-Vivo High-Resolution Magic Angle Spinning Proton MR Spectroscopy of Drosophila Melanogaster Flies as a Model System to Investigate Trauma, Innate Immunity and Aging

Burns are lesions often due to direct transfer of energy from any source of heat to the body. The thermal injury may determine severe metabolic alterations due to the liberation of inflammatory mediators and hormonal disturbances induced by stress. Burn trauma in skeletal muscle has both local and systematic effects, as functionally debilitating changes are seen to occur at local and distant site, especially when burn size exceeds 30% of total body surface area. Nuclear magnetic resonance Spectroscopy HRMAS has been used to explore lipidic accumulation after burn trauma. On these bases we perform a solid-state NMR method that maximizes the advantages of high-resolution magic-angle-spinning (HRMAS) 1H MRS applied to intact burn tissue biopsies when compared to more conventional liquid-state NMR approaches. Numerical simulations and experimental results of an optimized adiabatic TOBSY (Total through Bond correlation SpectroscopY) solidstate NMR pulse sequence for two-dimensional 1H-1H homonuclear scalar-coupling mixing indicate that a significant SNR gain (>100% theoretically and 20-50% experimentally) relative to its liquid-state analogue TOCSY (TOtal Correlation SpectroscopY) sequence is attainable. Multidimensional 1H-MRS is crucial for unambiguous assignment and quantification of overlapping 1H spectra of tissues. Hence, ensuring the best sensitivity is highly desirable. Here we present experiments using our novel 2D TOBSY HRMAS 1H MRS, which aim to suggest its use as a sensitive MR sequence to investigate burn metabolic injury.