TAT-Hsp70-mediated neuroprotection and increased survival of neuronal precursor cells after focal cerebral ischemia in mice.
Cerebral ischemia stimulates endogenous neurogenesis within the subventricular zone and the hippocampal dentate gyrus of the adult rodent brain. However, such newly generated cells soon die after cerebral ischemia. To enhance postischemic survival of neural precursor cells (NPC) and long-lasting neural regeneration, we applied the antiapoptotic chaperone heat shock protein 70 (Hsp70) fused to a cell-penetrating peptide derived from the HIV TAT to ensure delivery across the blood-brain barrier and the cell membrane. After transient focal cerebral ischemia in mice, TAT-Hsp70 was intravenously injected concomitant with reperfusion and additionally on day 14 after stroke. TAT-Hsp70 treatment resulted in smaller infarct size (27.1+/-9.0 versus 109.0+/-14.0 and 88.5+/-26.0 mm(3) in controls) and in functional improvement as assessed by the rota rod, tight rope, and water maze tests when compared with saline- and TAT-hemagglutinin-treated controls. In addition, postischemic survival of endogenous doublecortin (Dcx)-positive NPC was improved within the lesioned striatum of TAT-Hsp70-treated animals for up to 4 weeks after stroke without changing overall cell proliferation of BrdU(+) cells. Thus, TAT-Hsp70 treatment after stroke may be a promising tool to act neuroprotective and improve postischemic functional outcome, and also to increase survival of endogenous NPC after stroke.
Doeppner
Thorsten R
TR
Department of Neurology, University of Goettingen Medical School, Goettingen, Germany. thorsten.doeppner@medizin.uni-goettingen.de
Nagel
Florian
F
Dietz
Gunnar Ph
GP
Weise
Jens
J
Tönges
Lars
L
Schwarting
Sönke
S
Bähr
Mathias
M
D000818:Animals; D002545:Brain Ischemia / Q000188:drug therapy* / Q000473:pathology*; D001973:Bromodeoxyuridine / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D000089662:Doublecortin Protein; D015696:Gene Products, tat / Q000235:genetics / Q000378:metabolism / Q000627:therapeutic use*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism / Q000627:therapeutic use*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018696:Neuroprotective Agents / Q000378:metabolism / Q000627:therapeutic use*; D051381:Rats
C000714847:Dcx protein, mouse; C000714848:Dcx protein, rat; D000089662:Doublecortin Protein; D015696:Gene Products, tat; D018840:HSP70 Heat-Shock Proteins; D018696:Neuroprotective Agents; D001973:Bromodeoxyuridine