PROTEIN KINASE D1 MODULATION BY GENE THERAPY AS A NOVEL THERAPEUTIC APPROACH FOR AMYOTROPHIC LATERAL SCLEROSIS

AMONG THE PROGRESSIVE NEURODEGENERATIVE DISORDERS AFFECTING MOTONEURONS (MNS), AMYOTROPHIC LATERAL SCLEROSIS (ALS) IS THE MOST COMMON FORM. ALS IS A FATAL ADULT-ONSET NEURODEGENERATIVE DISEASE CAUSED BY SELECTIVE LOSS OF MOTONEURONS (MNS). ALS AFFECTS THOUSANDS OF PEOPLE EVERY YEAR IN EUROPE, PRODUCES IMPORTANT HEALTH CARE COSTS AND COMPROMISES FAMILY ECONOMY AND CAREGIVERS HEALTH. ALS IS A COMPLEX MULTIFACTORIAL DISEASE, A FACT THAT DIFFICULTS THE FINDING OF EFFECTIVE THERAPIES. ALTHOUGH MANY CELL TYPES SUFFER ALTERATIONS IN ALS, THE RESULT IS THAT MNS CANNOT MAINTAIN THEIR AXONAL PROJECTIONS AND THE APPROPRIATE MUSCLE INNERVATION. THUS, THE IDENTIFICATION AND EXPLORATION OF PLEIOTROPIC THERAPEUTIC TARGETS TO SIMULTANEOUSLY MODIFY SEVERAL PATHOLOGIC MECHANISMS AFFECTING MNS IS AN EMERGING CHALLENGE FOR ALS. PROTEIN KINASE D1 (PKD1) IS A MEMBER OF PKD PROTEINS FAMILY POORLY EXPLORED IN NEURONS, AND UNEXPLORED IN ALS. PKD1 ACTIVATION HELPS NEURONS TO FIGHT AGAINST OXIDATIVE STRESS AND APOPTOSIS, MODULATES SYNAPTIC PLASTICITY, NEURONAL MICROENVIRONMENT AND SEVERAL TRANSCRIPTION FACTORS, SUGGESTING THAT PKD1 ACTIVATION MAY POTENTIATE NEURONAL SURVIVAL. IN THE PKDALS PROJECT WE HYPOTHESIZE THAT I) DEACTIVATION OR UPSTREAM DYSREGULATION OF PKD1 OCCURS IN ALS PATHOPHYSIOLOGY AND THAT II) CONSEQUENTLY, SUSTAINED PKD1 ACTIVATION IN MICE AND IN HUMAN-DERIVED MNS MIGHT AMELIORATE THE COURSE OF THE DISEASE AND CELL TOXICITY RESPECTIVELY, PREVENTING MN DEGENERATION. THEREFORE, OVEREXPRESSION OF ACTIVE PKD1 BY GENE THERAPY BASED ON ADENOASSOCIATED VECTORS TO ACHIEVE HIGH AND SUSTAINED ACTIVATED PKD1 LEVELS IN MNS WILL BE EXPLORED AS A THERAPEUTIC TARGET FOR ALS DISEASE. TO CONFIRM OUR HYPOTHESIS, WE PLAN FOUR OBJECTIVES: I) TO INVESTIGATE THE ROLE OF PKD1 IN MN DEGENERATION, BY EVALUATING CHANGES OF PKD1 LEVELS AND ACTIVATION ALONG THE COURSE OF THE DISEASE IN THE TRANSGENIC SOD1G93A MICE; II) TO EVALUATE THE THERAPEUTIC EFFICACY OF A VIRAL VECTOR OVEREXPRESSING ACTIVE PKD1 BY INTRATHECAL ADMINISTRATION IN THE SOD1G93A MICE SPINAL CORD MNS; III) TO INVESTIGATE THE ROLE OF PKD1 IN MN DEGENERATION IN HUMANS, BY ASSESSING PKD1 LEVELS AND ACTIVATION IN SPINAL CORD TISSUE SAMPLES FROM ALS PATIENTS AND IN HUMAN INDUCED PLURIPOTENT STEM CELLS (IPSC)-DERIVED MNS FROM ALS PATIENTS AND IV) TO EVALUATE THE EFFICACY OF A VIRAL VECTOR OVEREXPRESSING ACTIVE PKD1 TO PREVENT MN DEATH IN CULTURES OF IPSC-DERIVED MNS FROM ALS PATIENTS SUBJECTED TO CELL STRESS. THE METHODOLOGIES PLANNED IN PKDALS ARE HIGHLY INTERDISCIPLINARY, BASED ON MOLECULAR AND CELLULAR BIOLOGY, ELECTROPHYSIOLOGY, MORPHOLOGY AND GENE THERAPY RESEARCH, APPLIED TO TRANSGENIC ALS MICE, INDUCED MNS DERIVED FROM ALS PATIENTS AND HUMAN SPINAL CORD SAMPLES. PKDALS FINDINGS AND RESULTS WILL IMPACT, IF SUCCESSFUL, FOR THE IMPROVEMENT OF QUALITY OF LIFE AND THE THERAPIES OF ALS PATIENTS.