Valproic acid influences the expression of genes implicated with hyperglycaemia-induced complement and coagulation pathways

Marina Barreto Felisbino,Camila Borges Martins De Oliveira,Assam El-Osta,Ishant Khurana,Keith Al-Hasani,Maria Luiza S Mello,Jun Okabe,K N Harikrishnan,Mark Ziemann,Scott Maxwell

doi:10.1038/s41598-021-81794-4

Abstract

Because the liver plays a major role in metabolic homeostasis and secretion of clotting factors and inflammatory innate immune proteins, there is interest in understanding the mechanisms of hepatic cell activation under hyperglycaemia and whether this can be attenuated pharmacologically. We have previously shown that hyperglycaemia stimulates major changes in chromatin organization and metabolism in hepatocytes, and that the histone deacetylase inhibitor valproic acid (VPA) is able to reverse some of these metabolic changes. In this study, we have used RNA-sequencing (RNA-seq) to investigate how VPA influences gene expression in hepatocytes. Interesting, we observed that VPA attenuates hyperglycaemia-induced activation of complement and coagulation cascade genes. We also observe that many of the gene activation events coincide with changes to histone acetylation at the promoter of these genes indicating that epigenetic regulation is involved in VPA action.

Highlights

Because the liver plays a major role in metabolic homeostasis and secretion of clotting factors and inflammatory innate immune proteins, there is interest in understanding the mechanisms of hepatic cell activation under hyperglycaemia and whether this can be attenuated pharmacologically
We have previously shown that treatment of HepG2 human hepatocytes with the HDACis Trichostatin A (TSA) and valproic acid (VPA) attenuated hepatic glucose production, no significant difference was detected in global chromatin structure and epigenetic landscape
In order to understand the effect of high glucose on whole genome hepatic gene expression, RNA-seq was performed on HepG2 cells cultured under continuous low glucose (LG) or stimulated with 48 h high glucose (HG; 20 mM) in triplicate

Summary

Introduction

Because the liver plays a major role in metabolic homeostasis and secretion of clotting factors and inflammatory innate immune proteins, there is interest in understanding the mechanisms of hepatic cell activation under hyperglycaemia and whether this can be attenuated pharmacologically. Several important coagulation pathway proteins are elevated by hyperglycaemia in vivo including fibrinogen, prothrombin 1 and 2, tissue factor, thrombin-antithrombin complexes, plasminogen activator inhibitor-1, tissue plasminogen activator and complement C3 which contribute to this hypercoagulative state[4,5,6] This prothrombotic state co-exist with chronic low-grade inflammation and oxidative s tress[7]. The recent discovery that histone deacetylase (HDAC) inhibitors (HDACi) have the ability to reduce the severity of inflammatory and autoimmune diseases, including diabetes, in several animal models, has positioned them as alternative anti-inflammatory a gents[18,19,20,21] Their paradigmatic mode of action has been defined as increased histone acetylation of target genes, leading to higher gene expression; recent studies have shown a more diverse mechanism of gene regulation[22,23,24,25]

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Results

Conclusion