The DNA repair enzyme, PARP-1, has emerged as a critical determinant of neuronal death in brain ischemia and other conditions. Work supported by this grant in the prior funding period elucidated the mechanism and role of bioenergetic failure in PARP-1 - mediated acute cell death, and identified several mechanisms by which PARP-1 activity is regulated. In the course of these studies we also identified a dominant role for PARP-1 in regulating microglial activation, MMP-9 release, and microglial-induced neuronal death. PARP-1 inhibitors are currently entering clinical trials for the treatment of stroke, myocardial ischemia, and other conditions as both cytoprotective and anti-inflammatory agents. Minocycline is also a PARP-1 inhibitor, and has also entered clinical trials for CNS disorders. However, the mechanism by which these compounds influence the inflammatory response remains poorly understood. This is an important translational question, because inflammation has beneficial as well as deleterious effects on brain recovery from stroke, with some aspects of the inflammatory response required for normal brain recovery after injury. A second, related question concerns the long-term consequences of PARP-1 inhibition. Given that PARP-1 is involved in DNA repair, and that PARP-1 deficient mice have an accelerated rate of mutagenesis, there is the possibility that treatment with PARP-1 inhibitors could increase DNA mutations in surviving cells, particularly in the setting of oxidative stress. Accumulated mutations could impact neuronal function and long term survival. The studies proposed here will address these related questions through three specific aims.
Aim 1 will establish the effect of PARP inhibitors on specific aspects of post-ischemic brain inflammation and recovery, Aim 2 will identify the mechanisms by which PARP-1 and PARG influence microglial activation, and Aim 3 will establish the effects of PARP and PARG inhibitors on DNA mutations induced by oxidative stress and stroke. Success with these studies will increase our understanding of regulatory processes in brain inflammation, the mechanisms by which PARP-1 and PARG inhibitors suppress brain inflammation, and the mutagenic potential of these agents when used in the post-ischemic setting.

Public Health Relevance

Stroke is a major cause of death and disability in the United States and throughout the world. Studies proposed here will evaluate an approach to suppressing inflammation in brain after stroke as a means of improving recovery from stroke. These studies will also establish a way to evaluate DNA mutations in brain caused by stroke and by post-stroke inflammation.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS041421-07
Application #
8252214
Study Section
Brain Injury and Neurovascular Pathologies Study Section (BINP)
Program Officer
Bosetti, Francesca
Project Start
2001-04-01
Project End
2015-05-31
Budget Start
2012-06-01
Budget End
2013-05-31
Support Year
7
Fiscal Year
2012
Total Cost
$311,697
Indirect Cost
$69,024
Name
Northern California Institute Research & Education
Department
Type
DUNS #
613338789
City
San Francisco
State
CA
Country
United States
Zip Code
94121
Robbins, Nathaniel M; Swanson, Raymond A (2014) Opposing effects of glucose on stroke and reperfusion injury: acidosis, oxidative stress, and energy metabolism. Stroke 45:1881-6
Chen, Y; Won, S J; Xu, Y et al. (2014) Targeting microglial activation in stroke therapy: pharmacological tools and gender effects. Curr Med Chem 21:2146-55
Swanson, Raymond A (2014) Glucose, acid, and aspartate: Friends and foes of the axon. Ann Neurol 75:490-1
Jain, Mohit; Ngoy, Soeun; Sheth, Sunil A et al. (2014) A systematic survey of lipids across mouse tissues. Am J Physiol Endocrinol Metab 306:E854-68
Cleaver, James E; Brennan-Minnella, Angela M; Swanson, Raymond A et al. (2014) Mitochondrial reactive oxygen species are scavenged by Cockayne syndrome B protein in human fibroblasts without nuclear DNA damage. Proc Natl Acad Sci U S A 111:13487-92
Baxter, Paul; Chen, Yanting; Xu, Yun et al. (2014) Mitochondrial dysfunction induced by nuclear poly(ADP-ribose) polymerase-1: a treatable cause of cell death in stroke. Transl Stroke Res 5:136-44
Swanson, Raymond A (2012) One cell's poison is another cell's cure. Nat Neurosci 15:505-6
d'Avila, Joana C; Lam, Tina I; Bingham, Deborah et al. (2012) Microglial activation induced by brain trauma is suppressed by post-injury treatment with a PARP inhibitor. J Neuroinflammation 9:31
Kauppinen, Tiina M; Suh, Sang Won; Higashi, Youichirou et al. (2011) Poly(ADP-ribose)polymerase-1 modulates microglial responses to amyloid *. J Neuroinflammation 8:152
Burns, David M; Ying, Weihai; Kauppinen, Tiina M et al. (2009) Selective down-regulation of nuclear poly(ADP-ribose) glycohydrolase. PLoS One 4:e4896

Showing the most recent 10 out of 25 publications