EFFECTS OF HYPERPHENYLALANINEMIA ON BRAIN METABOLISM AND NEURODEVELOPMENT IN PHENYLKETONURIA: A SYSTEMATIC REVIEW

Jhoycel A. Bakiki¹; Angelica B. Garalde¹; Maqui P. Macasieb¹; Gecelene C. Estorico¹’².

doi:10.5281/zenodo.21304703

Abstract

Hyperphenylalaninemia, or increased blood phenylalanine levels, is the outcome of phenylketonuria (PKU), an inherited metabolic condition caused by a deficiency of the enzyme phenylalanine hydroxylase. Elevated phenylalanine concentrations still have an impact on brain development and cognitive function, despite the fact that neonatal screening and nutritional treatment have greatly improved outcomes. The consequences of hyperphenylalaninemia on brain metabolism and neurodevelopment in PKU patients are investigated in this systematic study. Recent research indicates that too much phenylalanine affects neurotransmitter production, changes energy metabolism, interferes with myelination and neural maturation, and interferes with the transport of large neutral amino acids over the blood-brain barrier. This review highlights the relationship between longterm metabolic control and neurological outcomes and emphasizes the importance of early diagnosis in reducing the adverse effects of hyperphenylalaninemia on the brain.

Keywords

Cognitive function, brain metabolism, neurodevelopment, phenylketonuria, myelination

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