Targeted Disruption of Hsp110/105 Gene Protects Against Ischemic Stress

Background and Purpose— Hsp110/105 belongs to the HSP110 heat shock protein family, which is a subgroup of the HSP70 family. In mammals, Hsp110/105 is constitutively expressed but exhibits particularly high levels in the brain. It has recently been shown that both Hsp110/105 and Hsp70 are elevated after cerebral ischemia. To study the physiological role of this protein in vivo, we generated hsp110/105 knockout (KO) mice and investigate the effect of reduced Hsp110/105 levels on focal cerebral ischemia. Methods— hsp110/105 KO and wild-type mice were subjected to 30 minutes of transient middle cerebral artery occlusion followed by reperfusion for 24 hours. The infarct volume and neurological scores were measured and compared. The Hsp70 chaperone activity of thermally denatured firefly luciferase was measured in hsp110/105 KO embryonic fibroblasts. Results— The infarct volume and neurological deficit scores were significantly (P<0.05) reduced in hsp110/105 KO mice compared with wild-type controls. In additio...