347 - Decrease levels of miR-20b, miR-93 and miR-532 in Neonatal Encephalopathy Resolve in childhood and signify potential therapeutic targets.

Poster Number: 347
Publication Number: 347.3102

Background: Following Neonatal Encephalopathy (NE) children are at high risk of brain injury and poor outcomes later into childhood. MicroRNA (miRs) are ~21–23-nucleotide single-stranded RNA (ssRNAs) sequences that can be players in the immunopathology of NE and could be used as prognosis markers.

Objective: Assess the expression of miR-20a, miR-20b, miR-93 and miR-532 in neonates and children with NE and compare to healthy controls.

Design/Methods: The study included: Neonates with NE, control neonates, Children with NE and Control Children. Whole blood was stimulated with lipopolysaccharide (LPS). Total RNA was extracted from serum and identification of miR-20a, miR-20b, miR-93 and miR-532 was performed by TaqMan® Advanced miRNA Assays. miRNAs displayed as Delta CT levels.

Results: Forty-six children were recruited (n=11-12 in each group), Neonates’ samples were obtained in the first week of life and children’s samples at age 2-5 years. miR-20b, miR-93 and miR-532 were significantly decreased in neonates with NE when compared to neonatal controls. miR-20b expression increased in children with NE compared to neonates with NE, to similar levels to childhood controls. Meanwhile, miR-93 decreased in childhood controls compared to neonatal controls. Following an endotoxin challenge, miR-20b significantly increased with LPS in children with NE compared to their paired neonatal NE sample. miR-20a, miR-93 and miR-532 did not change significantly after endotoxin treatment compared to their corresponding basal samples within the group or when comparing control children to either neonates or children with NE.

Conclusion(s): miR-20b has been linked to neuron development and proliferation, while miR-93 and miR-532-5p are associated with homeostasis mechanisms protecting cells under stress conditions, such as autophagy, apoptosis and cell viability. Decreased levels of miR-20b, miR-93 and miR-532 in neonates with NE could be evidence of brain injury during that stage of life. Alterations in miRNAs at a specific time point may result in neurodevelopmental conditions later in life. Analysis of specific target genes would help to identify pathologic pathways and might have therapeutic value.