title: The circadian gene Rev-erbα improves cellular bioenergetics and provides preconditioning for protection against oxidative stress.
abstract: Diurnal oscillations in the expression of antioxidant genes imply that protection against oxidative stress is circadian-gated. We hypothesized that stabilization of the core circadian gene Rev-erbα (Nr1d1) improves cellular bioenergetics and protects against nutrient deprivation and oxidative stress. Compared to WT, mouse lung fibroblasts (MLG) stably transfected with a degradation resistant Rev-erbα (Ser(55/59) to Asp; hence referred to as SD) had 40% higher protein content, 1.5-fold higher mitochondrial area (confocal microscopy), doubled oxidative phosphorylation by high-resolution respirometry (Oroboros) and were resistant to glucose deprivation for 24h. This resulted from a 4-fold reduction in mitophagy (L3CB co-localized with MitoTracker Red) versus WT. Although PGC1α protein expression was comparable between SD and WT MLG cells, the role of mitochondrial biogenesis in explaining increased mitochondrial mass in SD cells was less clear. Embryonic fibroblasts (MEF) from C57Bl/6-SD transgenic mice, had a 9-fold induction of FoxO1 mRNA and increased mRNA of downstream antioxidant targets heme oxygenase-1 (HO-1), Mn superoxide dismutase and catalase (1.5, 2 fold and 2 fold respectively) versus WT. This allowed the SD cells to survive 1h incubation with 500 µM H2O2 as well as 24h of exposure to 95% O2 and remain attached whereas most WT cells did not. These observations establish a mechanistic link between the metabolic functions of Rev-erbα with mitochondrial homeostasis and protection against oxidative stress.
authors: Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; University of Pennsylvania, Philadelphia, PA 19104, USA.
authors: Shaon
authors: S
authors: Sengupta
authors: Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors: Guang
authors: G
authors: Yang
authors: University of Pennsylvania, Philadelphia, PA 19104, USA.
authors: John C
authors: JC
authors: O'Donnell
authors: Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors: Maurice D
authors: MD
authors: Hinson
authors: University of Pennsylvania, Philadelphia, PA 19104, USA; Division of Endocrinology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors: Shana E
authors: SE
authors: McCormack
authors: University of Pennsylvania, Philadelphia, PA 19104, USA; Division of Genetics and Metabolism, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors: Marni J
authors: MJ
authors: Falk
authors: Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors: Ping
authors: P
authors: La
authors: University of Pennsylvania, Philadelphia, PA 19104, USA; Division of Developmental and Behavioral Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors: Michael B
authors: MB
authors: Robinson
authors: Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors: Monica L
authors: ML
authors: Williams
authors: Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors: Mekdes T
authors: MT
authors: Yohannes
authors: Division of Genetics and Metabolism, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors: Erzsebet
authors: E
authors: Polyak
authors: University of Pennsylvania, Philadelphia, PA 19104, USA.
authors: Eiko
authors: E
authors: Nakamaru-Ogiso
authors: Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; University of Pennsylvania, Philadelphia, PA 19104, USA.
authors: Phyllis A
authors: PA
authors: Dennery
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000096:biosynthesis; D004734:Energy Metabolism / Q000235:genetics; D005347:Fibroblasts / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000096:biosynthesis; D006861:Hydrogen Peroxide / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D008928:Mitochondria / Q000235:genetics* / Q000378:metabolism; D056953:Nuclear Receptor Subfamily 1, Group D, Member 1 / Q000235:genetics / Q000378:metabolism*; D018384:Oxidative Stress / Q000235:genetics*; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha / Q000096:biosynthesis / Q000235:genetics; D013482:Superoxide Dismutase / Q000096:biosynthesis
chemical_list: D000975:Antioxidants; C498262:Nr1d1 protein, mouse; D056953:Nuclear Receptor Subfamily 1, Group D, Member 1; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D006861:Hydrogen Peroxide; D002374:Catalase; D051547:Heme Oxygenase-1; D013482:Superoxide Dismutase
keywords: Bioenergetics; Circadian; Energy metabolism; Mitochondria; NR1D1; Oxidative stress; Peroxisome proliferator‐activated receptor gamma coactivator 1‐alpha (PGC‐1α)(PPARGC1A); Preconditioning