GABA activates liver regeneration pathways through regulation of CDK9 activity after one hour

Research Authorship:

Maya Basic, Dr. Justin Nguyen, Dr. Fatima Rehman

Faculty Mentor:

Dr. Fatima Rehman | College of Arts and Sciences | Department of Biology

Abstract:

Liver regeneration after partial hepatectomy requires a rapid production of growth factors in order to induce the hepatocyte cell cycle. During this process RNA Polymerase II plays a big role in transcription of mRNA for proteins needed for hepatocytes to go through the cell cycle appropriately. Cyclic-dependent kinase 9 (CDK9) aids in this process by phosphorylating and regulating RNA Polymerase II. Previously we have found that Gamma-Aminobutyric acid (GABA) can help with liver regeneration and has been found to arrest hepatocytes at the G2 phase of the cell cycle. The purpose of this study is to examine if GABA exerts its effect on cell cycle through CDK9 upregulation or activation. HepaRG cells were treated with GABA in vitro and CDK9 expression was examined by immunofluorescence at 0, 1, and 8 hours post GABA treatment. Results showed that peak CDK9 activity occurred during the first hour after GABA treatment and helps support the hypothesis that GABA induce liver regeneration partially through regulation of CDK9. These findings can help elucidate the pathway responsible for GABA related liver regeneration.