Environmental enrichment attenuates the age-related decline in the mRNA expression of steroidogenic enzymes and reduces the methylation state of the steroid 5α-reductase type 1 gene in the rat hippocampus. (5th September 2015)

• Record Type: Journal Article
• Authors: Rossetti, María F.; Varayoud, Jorgelina; Moreno-Piovano, Guillermo S.; Luque, Enrique H.; Ramos, Jorge G.
• Is Part Of: Molecular and cellular endocrinology. Volume 412(2015)
• Page Start: 330
• Page End: 338
• Publication Date: 2015-09-05
• Subjects: Aging -- Environmental enrichment -- Hippocampus -- Neurosteroidogenic enzymes -- DNA methylation; 17β-HSD 17β-hydroxysteroid dehydrogenase -- 17β-HSD-3 17β-hydroxysteroid dehydrogenase type 3 -- 3α-HSD 3α-hydroxysteroid dehydrogenase -- 3β-HSD 3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase -- 5α-reductase steroid 5α-reductase -- 5α-reductase-1 steroid 5α-reductase type 1 -- AD Alzheimer's disease -- AP-1 activator protein 1 -- BDNF brain-derived neurotrophic factor -- CREB cAMP response element-binding protein -- Oct-1 octamer-binding factor-1 -- P450(11β)-1 11β-hydroxylase -- P450(11β)-2 aldosterone synthase -- P450(17α) cytochrome P450 17α-hydroxylase/c17, 20-lyase -- P450(2d4) cytochrome P4502d4 -- P450arom cytochrome P450arom -- P450scc cytochrome P450 side chain cleavage -- Sp1 selective promoter factor 1 -- SREBP- sterol regulatory element-binding protein -- StAR steroidogenic acute regulatory protein; Endocrinology -- Periodicals; Molecular biology -- Periodicals; Cytology -- Periodicals; Endocrinology -- Periodicals; Hormones -- Periodicals; Endocrinologie -- Périodiques; Cytology; Endocrinology; Molecular biology; Periodicals; 573.4
• DOI: 10.1016/j.mce.2015.05.024
• Languages: English
• ISSNs: 0303-7207

Abstract

Highlights: The mRNA expression of hippocampal steroidogenic enzymes decreases during aging. The promoter methylation of P450scc, 5α-reductase-1 and 3α-HSD increases in adults. Aged enriched rats show enhanced mRNA expression of neurosteroidogenic enzymes. An enriched environment reduces methylation of the 5α-reductase-1 gene. Abstract: We analyzed the effects of aging and environmental enrichment on the mRNA expression and DNA methylation state of steroidogenic enzymes in the hippocampus. The effects of aging were evaluated by comparing young adult (90-day-old) and middle-aged (450-day-old) female Wistar rats. To elucidate the effects of environmental enrichment, a subgroup of middle-aged rats exposed to sensory and social stimulation for 105 days was compared to rats housed under standard laboratory conditions. Aging decreased the transcription of neurosteroidogenic-related genes and increased the promoter methylation state of cytochrome P450 side chain cleavage, 3α-hydroxysteroid dehydrogenase (3α-HSD) and 5α-reductase-1. Exposure of middle-aged rats to environmental enrichment increased mRNA levels of 5α-reductase-1, 3α-HSD and cytochrome P450 17α-hydroxylase/c17, 20-lyase and decreased the methylation state of the 5α-reductase-1 gene. Thus, sensory and social stimulation attenuate the age-related decline in the mRNA expression of hippocampal steroidogenic enzymes. Epigenetic mechanisms associated with differential promoter methylation could be involved.