Authors :
Presenting Author: Haiying Shen, MD, PhD – University of Nebraska Medical Center
Sadie Baer, Msc – Legacy Research Institute; Becky Peng, BS – Molecular Vision Laboratory; Landon Phung, Msc – Legacy Research Institute; Raey Gesese, Bs – Legacy Research Institute
Rationale:
DNA methylation contributes to seizure development and epileptogenesis. We previously reported that sarcosine, a glycine transporter inhibitor, effectively reduced epileptogenesis in a rat kindling model, accompanied by reversal effects on seizure-related DNA methylation in rat hippocampus. This study aims to investigate the sarcosine effect on the hippocampal methylome in epileptogenesis.Methods:
Adult Sprague-Dawley rats were used for the kindling epileptogenesis model. Sarcosine (3g/kg. i.p.) versus saline vehicle was administrated to rats daily for five days during the kindling period. Reduced representation bisulfite sequencing (RRBS) and quantitative real-time PCR were used to quantify DNA methylation levels across the genome and to determine the mRNA levels of genes in epileptogenesis and sarcosine treatment. Differentially methylated regions (DMRs) were identified via bioinformatics analysis.
Results:
We demonstrated (i) a total of 516 DMRs in the hippocampus of kindled rats versus non-kindled controls, (ii) 341 DMRs were identified in the hippocampus of kindled rats with daily sarcosine treatment versus vehicle treatment, (iii) kindling epileptogenesis and sarcosine treatment produce substantial changes in 217 epiPathway and Gene Ontology; 13 pathways changes were identified under influences of epileptogenesis and sarcosine, (iv) the mRNA level of three genes (i.e., HDAC9, Smad7, and FOS genes,) among 12 selected genes with significant changes in DMRs, were identified with significant changes in epileptogenesis and sarcosine treatment.Conclusions:
Our findings demonstrated sarcosine-mediated epigenetic changes that affect the expression of epilepsy-associated genes.Funding: Good Samaritan Research Foundation; NIH R01 NS084920