title: Modulation of the peroxisomal gene expression pattern by dehydroepiandrosterone and vitamin D: therapeutic implications.
abstract: Peroxisomes are ubiquitous organelles required for several metabolic functions. Their dysfunction is responsible for a group of human inherited disorders. In the search for endogenous factors regulating the peroxisomal compartment in normal liver, we treated female rats with dehydroepiandrosterone (DHEA) and 25-hydroxycholecalciferol for 1 and 6 days. Relative transcription levels of 39 selected genes were evaluated by real-time quantitative RT-PCR analysis. Catalase (peroxisomal marker)-specific activity was assayed in total liver homogenate and peroxisomes were visualized by catalase localization. DHEA induced peroxisome proliferation and raised catalase specific activity. Expression levels of 16 (of which 11 were peroxisomal) genes were altered. Pex 11, acyl-CoA oxidase,l - andd -multifunctional enzyme, thiolase 1, phytanoyl-CoA hydroxylase, 70 kDa peroxisomal membrane protein and very long chain acyl-CoA synthetase were upregulated, three others were downregulated. Vitamin D caused downregulation of six genes. Administration of vitamin D to peroxisomal disorder patients may be contraindicated. The adrenocortical hormone DHEA is a potential natural regulator of the peroxisomal compartment. Its therapeutic use in X-linked adrenoleukodystrophy, some other beta-oxidation defects and classical Refsum should be considered.
authors.affiliation: Department of Human Anatomy, Embryology, Histology and Medical Physics, Ghent University, Godshuizenlaan 4, B-9000 Ghent, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Depreter
authors.forename: J
authors.initials: J
authors.lastname: Vandesompele
authors.forename: M
authors.initials: M
authors.lastname: Espeel
authors.forename: F
authors.initials: F
authors.lastname: Speleman
authors.forename: F
authors.initials: F
authors.lastname: Roels
mesh_terms: D000818:Animals; D001483:Base Sequence; D002112:Calcifediol / Q000494:pharmacology*; D002374:Catalase / Q000032:analysis; D000075202:Contraindications; D017931:DNA Primers / Q000235:genetics; D003687:Dehydroepiandrosterone / Q000494:pharmacology*; D004789:Enzyme Activation; D005260:Female; D015870:Gene Expression; D005786:Gene Expression Regulation / Q000187:drug effects*; D008099:Liver / Q000378:metabolism*; D008969:Molecular Sequence Data; D018901:Peroxisomal Disorders / Q000188:drug therapy; D020675:Peroxisomes / Q000201:enzymology / Q000235:genetics*; D019946:Propylene Glycol / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D003687:Dehydroepiandrosterone; D019946:Propylene Glycol; D002374:Catalase; D002112:Calcifediol