Project description:LC-MS/MS protein data of Primary Human Hepatocytes (PHH) exposed to Valproic Acid (VPA) for 3 days daily and 3 days daily exposure followed by 3 days washout.
Project description:Study hypothesis: Increasing folate status and the MethyleneTetraHydroFolate Reductase (MTHFR) C677T genotype influence intermediary biomarkers of preclinical neoplasia (DeoxyriboNucleic Acid [DNA] methylation and uracil misincorporation) in human colonic epithelium.
Primary outcome(s): Changes in genomic and gene specific DNA methylation and uracil misincorporation.
Project description:Valproic acid (VPA) is a very potent anti-cancer and neuro-protective drug. However, exposure to VPA may cause accumulation of lipids in the liver which could result in the development of steatosis. As VPA is a fatty acid analogue, most of the performed studies focus on inhibition of the mitochondrial b-oxidation pathway as the possible mode of action. However, investigations exploring the contribution of other processes in particular by using whole genome studies in a relevant human liver model are limited. Furthermore, the contribution of gene expression regulation by DNA methylation changes and/or miRNA changes is hardly known. Therefore, in the present study, we investigated the effect of repetitive VPA exposure on primary human hepatocytes (PHH) on whole genome gene expression-, DNA methylation-, and miRNA changes, using microarrays and integrated data analyses. PHH were exposed to a non-cytotoxic dose of 15 mM VPA for 5 days daily thereby inducing accumulation of lipids. Part of the PHH was left untreated for an additional 3 days in order to study the persistence of changes. VPA modulated the expression of a number of nuclear receptors and their target genes, leading to disturbed fatty acid metabolism and - uptake, ultimately leading to accumulation of triglycerides in the liver which is the key event leading to steatosis. Part of the gene expression changes was epigenetically regulated. Furthermore, after terminating the treatment, the expression and DNA methylation changes of several genes remained persistent, indicating a permanent change in the PHH, causing steatosis development to continue and/or making the PHH more sensitive for steatosis development during a subsequent exposure.
Project description:Valproic acid (VPA) is a very potent anti-cancer and neuro-protective drug. However, exposure to VPA may cause accumulation of lipids in the liver which could result in the development of steatosis. As VPA is a fatty acid analogue, most of the performed studies focus on inhibition of the mitochondrial b-oxidation pathway as the possible mode of action. However, investigations exploring the contribution of other processes in particular by using whole genome studies in a relevant human liver model are limited. Furthermore, the contribution of gene expression regulation by DNA methylation changes and/or miRNA changes is hardly known. Therefore, in the present study, we investigated the effect of repetitive VPA exposure on primary human hepatocytes (PHH) on whole genome gene expression-, DNA methylation-, and miRNA changes, using microarrays and integrated data analyses. PHH were exposed to a non-cytotoxic dose of 15 mM VPA for 5 days daily thereby inducing accumulation of lipids. Part of the PHH was left untreated for an additional 3 days in order to study the persistence of changes. VPA modulated the expression of a number of nuclear receptors and their target genes, leading to disturbed fatty acid metabolism and - uptake, ultimately leading to accumulation of triglycerides in the liver which is the key event leading to steatosis. Part of the gene expression changes was epigenetically regulated. Furthermore, after terminating the treatment, the expression and DNA methylation changes of several genes remained persistent, indicating a permanent change in the PHH, causing steatosis development to continue and/or making the PHH more sensitive for steatosis development during a subsequent exposure.
Project description:Valproic acid (VPA) is a very potent anti-cancer and neuro-protective drug. However, exposure to VPA may cause accumulation of lipids in the liver which could result in the development of steatosis. As VPA is a fatty acid analogue, most of the performed studies focus on inhibition of the mitochondrial b-oxidation pathway as the possible mode of action. However, investigations exploring the contribution of other processes in particular by using whole genome studies in a relevant human liver model are limited. Furthermore, the contribution of gene expression regulation by DNA methylation changes and/or miRNA changes is hardly known. Therefore, in the present study, we investigated the effect of repetitive VPA exposure on primary human hepatocytes (PHH) on whole genome gene expression-, DNA methylation-, and miRNA changes, using microarrays and integrated data analyses. PHH were exposed to a non-cytotoxic dose of 15 mM VPA for 5 days daily thereby inducing accumulation of lipids. Part of the PHH was left untreated for an additional 3 days in order to study the persistence of changes. VPA modulated the expression of a number of nuclear receptors and their target genes, leading to disturbed fatty acid metabolism and - uptake, ultimately leading to accumulation of triglycerides in the liver which is the key event leading to steatosis. Part of the gene expression changes was epigenetically regulated. Furthermore, after terminating the treatment, the expression and DNA methylation changes of several genes remained persistent, indicating a permanent change in the PHH, causing steatosis development to continue and/or making the PHH more sensitive for steatosis development during a subsequent exposure.
Project description:Early during culture of primary mouse HSCs gene expression changes. These expression alterations can be affected by treating cells with histone deacetylase inhibitor, valproic acid Primary mouse Hepatic stellate cells were cultured for short periods of time (4-16-64h) in presence or absence of valproic acid. Gene expression analysis (mouse Gene 1.0 ST arrays according to manufacturerM-bM-^@M-^Ys manual 701880Rev4 (Affymetrix, Santa Clara, CA)), in vitro stellate cell activation and inhibition of the activation by valproic acid treatment.
Project description:Early during culture of primary mouse HSCs gene expression changes. These expression alterations can be affected by treating cells with histone deacetylase inhibitor, valproic acid