Transcriptome Profiling of Phenylalanine-Treated Human Neuronal Model: Spotlight on Neurite Impairment and Synaptic Connectivity

• Published in: International journal of molecular sciences Vol. 25; no. 18; p. 10019
• Main Authors: Stankovic, Sara, Lazic, Andrijana, Parezanovic, Marina, Stevanovic, Milena, Pavlovic, Sonja, Stojiljkovic, Maja, Klaassen, Kristel
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 18-09-2024; MDPI
• Subjects: Axons; Brain research; Cell Differentiation - drug effects; Cells; Cognition disorders; Complications and side effects; Dendrites; Development and progression; Diet; Disease; Enzymes; Gene expression; gene expression profile; Gene Expression Profiling; Gene Expression Regulation - drug effects; Genotype & phenotype; Health aspects; Humans; Intellectual disabilities; Medical screening; Metabolism; Neural circuitry; neurite impairment; Neurites - drug effects; Neurites - metabolism; Neurons; Neurons - drug effects; Neurons - metabolism; Neuropathology; Neurosciences; NT2-derived neurons; Pathophysiology; Phenylalanine - pharmacology; Phenylketonuria; Phenylketonurias - genetics; Phenylketonurias - metabolism; Physiological aspects; Proteins; Risk factors; RNA sequencing; Synapses - drug effects; Synapses - metabolism; Transcriptome; Serbia; RNA sequencing; synaptic connectivity; transcriptome; neurite impairment; gene expression profile; NT2-derived neurons; phenylketonuria
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms251810019

Phenylketonuria (PKU) is the most common inherited disorder of amino acid metabolism, characterized by high levels of phenylalanine (Phe) in the blood and brain, leading to cognitive impairment without treatment. Nevertheless, Phe-mediated brain dysfunction is not fully understood. The objective of this study was to address gene expression alterations due to excessive Phe exposure in the human neuronal model and provide molecular advances in PKU pathophysiology. Hence, we performed NT2/D1 differentiation in culture, and, for the first time, we used Phe-treated NT2-derived neurons (NT2/N) as a novel model for Phe-mediated neuronal impairment. NT2/N were treated with 1.25 mM, 2.5 mM, 5 mM, 10 mM, and 30 mM Phe and subjected to whole-mRNA short-read sequencing. Differentially expressed genes (DEGs) were analyzed and enrichment analysis was performed. Under three different Phe concentrations (2.5 mM, 5 mM, and 10 mM), DEGs pointed to the
,
,
,
,
,
and
genes, placing them in the context of PKU for the first time. Enriched processes included dendrite and axon impairment, synaptic transmission, and membrane assembly. In contrast to these groups, the 30 mM Phe treatment group clearly represented the neurotoxicity of Phe, exhibiting enrichment in apoptotic pathways. In conclusion, we established NT2/N as a novel model for Phe-mediated neuronal dysfunction and outlined the Phe-induced gene expression changes resulting in neurite impairment and altered synaptic connectivity.