Acetyl L carnitine physical chemical, metabolic, and therapeutic properties: relevance for its mode of action in Alzheimer's disease and geriatric depression Molecular Psychiatry Nitric Oxide Supplement Allergy Research Group Frontiers Discovery and validation of acetyl L carnitine in serum for diagnosis of major depressive disorder and remission status through metabolomic approach Carnitine Deficiency in Chronic Kidney Disease: Pathophysiology, Clinical Implications, and Therapeutic Perspectives