PR000575 (Project)

Description:The loss of myelin, degeneration of the myelin producing oligodendroglia and impaired remyelination are essential features of traumatic spinal cord injury (SCI) that significantly limit patient recovery of function. The lipid rich composition of myelin, including exceptionally high levels of saturated fatty acids, underlie its essential physiological roles, including its structural and signaling properties and electrical insulation of axons to facilitate the conduction of nerve impulses. The myelin sheaths also provide metabolic support to the axons they wrap, and myelin health is therefore essential to the maintenance of axon integrity and function in the brain and spinal cord. The primary goal of this Pilot Proposal to the Mayo Clinic Metabolomics Core is to integrate highly sensitive metabolomics liquid chromatography-tandem mass spectrometry (LC/MS/MS) assays to quantify the lipid composition of the myelin membrane, with our conventional neurobehavioral approaches, enabling us to explore the metabolic basis of new interventions capable of promoting myelin regeneration and restoration of patient function. Metabolomics Core expertise in Magnetic Resonance Spectroscopy (NMR) based evaluation of key metabolites involved in CNS injury and repair (N-acetyl-L-aspartate, choline, myo-inositol, glucose/ glutamine and lactate) will also be applied to strengthen our mechanistic understanding of myelin injury and repair. Specifically, utilizing these innovative approaches we will test a novel hypothesis driven by new preliminary findings that the levels of dietary fatty acids can be optimized alone, or in combination with exercise training, to facilitate myelin regeneration and recovery of neurobehavioral function after injury to the adult spinal cord. In Aim 1, we will determine whether alterations in dietary fat, including saturated fat or omega-3 fatty acids, facilitate restoration of the myelin membrane and metabolite signatures of central nervous system repair after experimental SCI in adult mice. In Aim 2, we will determine whether exercise training alone or in combination with dietary fatty acid supplementation fosters myelin regeneration and recovery of function after experimental SCI. The proposed studies will leverage the expertise of the Mayo Metabolomics Core with that of Dr. Scarisbrick (Mayo) in myelin biology and Dr. Gomez Pinilla (UCLA) in central nervous system plasticity to investigate whether two highly targetable lifestyle variables, that is diet and exercise, can be modulated to improve myelin metabolism and functional recovery after SCI.