Abstract | PURPOSE: METHODS: For the oxygen-induced retinopathy (OIR) model, wild-type (WT), and PPARα knockout (PPARα(-/-)) mice were exposed to 75% O₂ from postnatal day 7 (P7) to P12 and treated with the PPARα agonist fenofibric acid (Feno-FA) from P12 to P16. At P17, the effects of Feno-FA on retinal glial fibrillary acidic protein (GFAP) expression, apoptotic DNA cleavage, and TUNEL labeling were analyzed. Cultured retinal cells were exposed to CoCl₂ to induce hypoxia, and TUNEL staining and 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein dye were used to measure apoptosis and reactive oxygen species (ROS) generation. Western blotting was used to measure GFAP levels and cell signaling. RESULTS: Feno-FA decreased retinal apoptosis and oxidative stress in WT but not PPARα(-/-) OIR mice. Peroxisome proliferator-activated receptor-alpha knockout OIR mice showed increased retinal cell death and glial activation in comparison to WT OIR mice. Feno-FA treatment and PPARα overexpression protected cultured retinal cells from hypoxic cell death and decreased ROS levels. Nuclear hypoxia-inducible factor-α (HIF-1α) and nicotine adenine dinucleotide phosphate oxidase-4 (Nox 4) were increased in OIR retinas and downregulated by Feno-FA in WT but not in PPARα(-/-) mice. CONCLUSIONS:
Peroxisome proliferator-activated receptor-alpha has a potent antiapoptotic effect in the ischemic retina. This protective effect may be mediated in part through downregulation of HIF-1α/Nox 4 and consequently alleviation of oxidative stress.
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Authors | Elizabeth Moran, Lexi Ding, Zhongxiao Wang, Rui Cheng, Qian Chen, Robert Moore, Yusuke Takahashi, Jian-xing Ma |
Journal | Investigative ophthalmology & visual science
(Invest Ophthalmol Vis Sci)
Vol. 55
Issue 7
Pg. 4568-76
(May 13 2014)
ISSN: 1552-5783 [Electronic] United States |
PMID | 24825105
(Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
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Copyright | Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc. |
Chemical References |
- Antioxidants
- Glial Fibrillary Acidic Protein
- Hif1a protein, mouse
- Hypolipidemic Agents
- Hypoxia-Inducible Factor 1, alpha Subunit
- Nerve Tissue Proteins
- PPAR alpha
- Reactive Oxygen Species
- glial fibrillary astrocytic protein, mouse
- fenofibric acid
- NADPH Oxidase 4
- NADPH Oxidases
- Nox4 protein, mouse
- Oxygen
- Fenofibrate
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Topics |
- Animals
- Animals, Newborn
- Antioxidants
(physiology)
- Apoptosis
(drug effects)
- Blotting, Western
- Cells, Cultured
- Disease Models, Animal
- Enzyme-Linked Immunosorbent Assay
- Fenofibrate
(analogs & derivatives, therapeutic use)
- Glial Fibrillary Acidic Protein
- Hypolipidemic Agents
(therapeutic use)
- Hypoxia-Inducible Factor 1, alpha Subunit
(metabolism)
- In Situ Nick-End Labeling
- Ischemia
(metabolism, pathology, prevention & control)
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- NADPH Oxidase 4
- NADPH Oxidases
(metabolism)
- Nerve Tissue Proteins
(metabolism)
- Oxidative Stress
(drug effects)
- Oxygen
(toxicity)
- PPAR alpha
(agonists, physiology)
- Reactive Oxygen Species
(metabolism)
- Retinal Diseases
(metabolism, pathology, prevention & control)
- Retinal Vessels
(physiopathology)
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