gw-1929 and Brain-Ischemia

Transient global cerebral ischemia results in acute neurodegeneration in selective brain areas. Global cerebral ischemic-reperfusion (IR) injury induced selective hippocampal damage results into various neurobehavioral deficits including spatial memory and learning deficiencies. In this study, we have investigated the protective effects of a nonthiazolidinedione PPARγ agonist, N-(2-benzoylphenyl)-O-[2-(methyl-2-pyridinylamino)ethyl]-l-tyrosine (GW1929), against global cerebral IR injury induced neurobehavioral deficits and brain damage in gerbils. Bilateral carotid artery occlusion induced global cerebral ischemia in gerbils resulted in neurological deficits, hyperlocomotion, reduced response latency in passive avoidance test and hippocampal damage. Hippocampal neurodegeneration after cerebral IR injury was also associated with significant increase in iNOS and MMP-9 immunoreactivity along with TNFα and IL-6 levels. Massive apoptotic DNA fragmentation as evident from increased TUNEL (terminal deoxynucleotidyl transferase mediated dUTP nick end labelling)-positive cells was also observed in the CA1 hippocampal region of IR challenged gerbils. GW1929 treatment significantly ameliorated cerebral IR induced neurological symptoms, hyperlocomotion, cognitive deficits and hippocampal neuronal damage in CA1 hippocampus region in gerbils. Significant reduction in IR injury induced iNOS and MMP-9 immunoreactivity, TNFα and IL-6 levels and apoptotic DNA fragmentation was also observed with GW1929 treatment. Pioglitazone, thiazolidinedione PPARγ agonist also exhibited similar effects on inflammatory parameters after global cerebral IR injury. In summary, this study demonstrates neuroprotective effects of GW1929 in global cerebral IR injury induced neurobehavioral deficits and brain pathology which may be attributed to reduced inflammation and apoptotic DNA fragmentation, suggesting therapeutic potential of PPARγ agonists in cerebral IR injury.

Topics: Analysis of Variance; Animals; Benzophenones; Brain Damage, Chronic; Brain Ischemia; Cognition Disorders; DNA Fragmentation; Gerbillinae; Hippocampus; Male; Motor Activity; Neuroprotective Agents; PPAR gamma; Reperfusion Injury; Tyrosine

PPARγ agonist; 2-(Benzoylphenyl)-O-[2-(methyl-2-pyridinylamino) ethyl]-L-tyrosine (GW1929) in focal cerebral ischemic-reperfusion (IR) injury in rats. Focal cerebral IR injury resulted significant brain infarction and neurological deficits in rats. A significant increase in various inflammatory mediators like COX-2, iNOS, MMP-9, TNFα and IL-6 and massive apoptotic DNA fragmentation was also observed in the IR challenged brains. GW1929 treatment significantly attenuated the neurological damage in focal cerebral IR injury. Neuroprotective effects of GW1929 were found to be associated with significant reduction in the COX-2, iNOS, MMP-9, TNFα and IL-6 levels. Together, we have also evaluated the effects of Pioglitazone, a clinically available thiazolidinedione PPARγ agonist, against focal cerebral IR injury. Like GW1929, Pioglitazone also showed beneficial effects in cerebral IR injury associated neurological damage but at the higher dose as compared to GW1929. Neuroprotective effects of PPARγ agonists were found to be associated with significant reduction in TUNEL positive cells in IR challenged brain. In summary, these results suggested the neuroprotective potential of PPARγ agonists in cerebral IR injury and these effects may be attributed to their anti-inflammatory and anti-apoptotic potential.

Topics: Animals; Apoptosis; Benzophenones; Brain Ischemia; Enzyme-Linked Immunosorbent Assay; Immunohistochemistry; In Situ Nick-End Labeling; Inflammation; Male; Neuroprotective Agents; PPAR gamma; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tyrosine