Post-Stroke Inhibition of Induced NADPH Oxidase Type 4 Prevents Oxidative Stress and Neurodegeneration

• Published in: PLoS biology Vol. 8; no. 9; p. e1000479
• Main Authors: Kleinschnitz, Christoph, Grund, Henrike, Wingler, Kirstin, Armitage, Melanie E., Jones, Emma, Mittal, Manish, Barit, David, Schwarz, Tobias, Geis, Christian, Kraft, Peter, Barthel, Konstanze, Schuhmann, Michael K., Herrmann, Alexander M., Meuth, Sven G., Stoll, Guido, Meurer, Sabine, Schrewe, Anja, Becker, Lore, Gailus-Durner, Valérie, Fuchs, Helmut, Klopstock, Thomas, de Angelis, Martin Hrabé, Jandeleit-Dahm, Karin, Shah, Ajay M., Weissmann, Norbert, Schmidt, Harald H. H. W.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.09.2010; Public Library of Science (PLoS)
• Subjects: Animals; Antioxidants; Blood clots; Blood-Brain Barrier; Brain - metabolism; Brain - pathology; Brain damage; Cardiovascular Disorders/Cardiovascular Pharmacology; Colleges & universities; Drug therapy; Female; Genetics and Genomics/Gene Function; Health aspects; Ischemia; Male; Mice; Mice, Knockout; Mortality; NADPH Oxidase 4; NADPH Oxidases - antagonists & inhibitors; NADPH Oxidases - genetics; NADPH Oxidases - metabolism; Neurodegeneration; Neurological Disorders/Cerebrovascular Disease; Neurological Disorders/Neuropharmacology; Nitric oxide; Non-Clinical Medicine/Research Methods; Oxidases; Oxidative Stress; Pharmacology/Drug Development; Phenotype; Physiology/Cardiovascular Physiology and Circulation; Prevention; Reactive Oxygen Species - metabolism; Stroke; Stroke (Disease); Stroke - enzymology; Stroke - metabolism; Stroke - pathology; Veins & arteries; United Kingdom; Brain; Phenotype; Stroke; Animals; Reactive Oxygen Species; Oxidative Stress; Female; Male; Mice; Blood-Brain Barrier; Mice, Knockout; NADPH Oxidase
• ISSN: 1545-7885; 1544-9173; 1545-7885
• DOI: 10.1371/journal.pbio.1000479

Ischemic stroke is the second leading cause of death worldwide. Only one moderately effective therapy exists, albeit with contraindications that exclude 90% of the patients. This medical need contrasts with a high failure rate of more than 1,000 pre-clinical drug candidates for stroke therapies. Thus, there is a need for translatable mechanisms of neuroprotection and more rigid thresholds of relevance in pre-clinical stroke models. One such candidate mechanism is oxidative stress. However, antioxidant approaches have failed in clinical trials, and the significant sources of oxidative stress in stroke are unknown. We here identify NADPH oxidase type 4 (NOX4) as a major source of oxidative stress and an effective therapeutic target in acute stroke. Upon ischemia, NOX4 was induced in human and mouse brain. Mice deficient in NOX4 (Nox4(-/-)) of either sex, but not those deficient for NOX1 or NOX2, were largely protected from oxidative stress, blood-brain-barrier leakage, and neuronal apoptosis, after both transient and permanent cerebral ischemia. This effect was independent of age, as elderly mice were equally protected. Restoration of oxidative stress reversed the stroke-protective phenotype in Nox4(-/-) mice. Application of the only validated low-molecular-weight pharmacological NADPH oxidase inhibitor, VAS2870, several hours after ischemia was as protective as deleting NOX4. The extent of neuroprotection was exceptional, resulting in significantly improved long-term neurological functions and reduced mortality. NOX4 therefore represents a major source of oxidative stress and novel class of drug target for stroke therapy.