Role of Phenylalanine and Its Metabolites in Health and Neurological Disorders

The document reviewed the role of phenylalanine, an essential amino acid, in health and neurological disorders, emphasizing its potential as an antidepressant and its involvement in neurotransmitter formation. It highlighted phenylketonuria (PKU), a genetic disorder caused by phenylalanine hydroxylase deficiency, leading to phenylalanine accumulation and associated symptoms like intellectual disability. Management of PKU required a low-phenylalanine diet and lifelong monitoring. The document also discussed phenylalanine's role in treating vitiligo, weight management, and its interaction with drugs like levodopa. Studies showed phenylalanine improved symptoms in some depressed patients, but side effects included insomnia and increased blood pressure. The review concluded that phenylalanine hydroxylase deficiency led to intolerance to dietary phenylalanine, causing various syndromes and cognitive disabilities.