Deletion of the ageing gene p66(Shc) reduces early stroke size following ischaemia/reperfusion brain injury.

Abstract

AIMS:

Stroke is a leading cause of morbidity and mortality, and its incidence increases with age. Both in animals and in humans, oxidative stress appears to play an important role in ischaemic stroke, with or without reperfusion. The adaptor protein p66(Shc) is a key regulator of reactive oxygen species (ROS) production and a mediator of ischaemia/reperfusion damage in ex vivo hearts. Hence, we hypothesized that p66(Shc) may be involved in ischaemia/reperfusion brain damage. To this end, we investigated whether genetic deletion of p66(Shc) protects from ischaemia/reperfusion brain injury.

METHODS AND RESULTS:

Transient middle cerebral artery occlusion (MCAO) was performed to induce ischaemia/reperfusion brain injury in wild-type (Wt) and p66(Shc) knockout mice (p66(Shc-/-)), followed by 24 h of reperfusion. Cerebral blood flow and blood pressure measurements revealed comparable haemodynamics in both experimental groups. Neuronal nuclear antigen immunohistochemical staining showed a significantly reduced stroke size in p66(Shc-/-) when compared with Wt mice (P < 0.05, n = 7-8). In line with this, p66(Shc-/-) mice exhibited a less impaired neurological function and a decreased production of free radicals locally and systemically (P < 0.05, n = 4-5). Following MCAO, protein levels of gp91phox nicotinamide adenine dinucleotide phosphate oxidase subunit were increased in brain homogenates of Wt (P < 0.05, n = 4), but not of p66(Shc-/-) mice. Further, reperfusion injury in Wt mice induced p66(Shc) protein in the basilar and middle cerebral artery, but not in brain tissue, suggesting a predominant involvement of vascular p66(Shc).

CONCLUSION:

In the present study, we show that the deletion of the ageing gene p66(Shc) protects mice from ischaemia/reperfusion brain injury through a blunted production of free radicals. The ROS mediator p66(Shc) may represent a novel therapeutical target for the treatment of ischaemic stroke.

• Authors: Remo D Spescha, Yi Shi, Susanne Wegener, Stephan Keller, Bruno Weber, Matthias M Wyss, Nadine Lauinger, Ghazaleh Tabatabai, Francesco Paneni, Francesco Cosentino, Christoph Hock, Michael Weller, Roger M Nitsch, Thomas F Lüscher, Giovanni G Camici
• Journal: European heart journal (Eur Heart J) Vol. 34 Issue 2 Pg. 96-103 (Jan 2013) ISSN: 1522-9645 [Electronic] England
• PMID: 23008506 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Membrane Glycoproteins
• Reactive Oxygen Species
• Shc Signaling Adaptor Proteins
• Shc1 protein, mouse
• Src Homology 2 Domain-Containing, Transforming Protein 1
• Cybb protein, mouse
• NADPH Oxidase 2
• NADPH Oxidases

Topics

• Animals
• Blood Flow Velocity (physiology)
• Blood Pressure (physiology)
• Brain Diseases (physiopathology)
• Cerebrovascular Circulation (physiology)
• Gene Deletion
• Infarction, Middle Cerebral Artery (genetics, physiopathology)
• Male
• Membrane Glycoproteins (metabolism)
• Mice
• Mice, Knockout
• NADPH Oxidase 2
• NADPH Oxidases (metabolism)
• Oxidative Stress (genetics)
• Reactive Oxygen Species (metabolism)
• Reperfusion Injury (genetics)
• Shc Signaling Adaptor Proteins (genetics)
• Src Homology 2 Domain-Containing, Transforming Protein 1
• Stroke (genetics, physiopathology)