Putative endogenous mediators of preconditioning-induced ischemic tolerance in rat brain identified by genomic and proteomic analysis.
In brain, a brief ischemic episode induces protection against a subsequent severe ischemic insult. This phenomenon is known as preconditioning-induced neural ischemic tolerance. An understanding of the molecular mechanisms leading to preconditioning helps in identifying potential therapeutic targets for preventing the post-stroke brain damage. The present study conducted the genomic and proteomic analysis of adult rat brain as a function of time following preconditioning induced by a 10-min transient middle cerebral artery (MCA) occlusion. GeneChip analysis showed induction of 40 putative neuroprotective transcripts between 3 to 72 h after preconditioning. These included heat-shock proteins, heme oxygenases, metallothioneins, signal transduction mediators, transcription factors, ion channels and apoptosis/plasticity-related transcripts. Real-time PCR confirmed the GeneChip data for the transcripts up-regulated after preconditioning. Two-dimensional gel electrophoresis combined with MALDI-TOF analysis showed increased expression of HSP70, HSP27, HSP90, guanylyl cyclase, muskelin, platelet activating factor receptor and beta-actin at 24 h after preconditioning. HSP70 protein induction after preconditioning was localized in the cortical pyramidal neurons. The infarct volume induced by focal ischemia (1-h MCA occlusion) was significantly smaller (by 38 +/- 7%, p < 0.05) in rats subjected to preconditioning 3 days before the insult. Preconditioning also prevented several gene expression changes induced by focal ischemia.
Dhodda
Vinay K
VK
Department of Neurological Surgery, University of Wisconsin-Madison, Madison, Wisconsin 53792, USA. vemugant@neurosirg.wisc.edu
Sailor
Kurt A
KA
Bowen
Kellie K
KK
Vemuganti
Raghu
R
D000818:Animals; D001921:Brain / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology; D004195:Disease Models, Animal; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000502:physiology; D023281:Genomics; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D019194:Ischemic Preconditioning; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D040901:Proteomics; D051381:Rats; D011918:Rats, Inbred SHR; D015398:Signal Transduction / Q000235:genetics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013997:Time Factors; D015854:Up-Regulation / Q000235:genetics
D018840:HSP70 Heat-Shock Proteins