The role of the complement cascade in ischemia/reperfusion injury: implications for neuroprotection.
BACKGROUND
The complement cascade plays a deleterious role in multiple models of ischemia/reperfusion (I/R) injury, including stroke. Investigation of the complement cascade may provide a critical approach to identifying neuroprotective strategies that can be effective at clinically relevant time points in cerebral ischemia. This review of the literature describes the deleterious effects of complement activation in systemic I/R models and previous attempts at therapeutic complement inhibition, with a focus on the potential role of complement inhibition in ischemic neuroprotection. Translation of these concepts into ischemic stroke models and exploration of related neuroprotective strategies are also reviewed.


RESULTS
We performed a MEDLINE search to identify any studies published between 1966 and 2001 dealing with complement activation in the setting of I/R injury. We also searched for studies demonstrating up-regulation of any complement components within the central nervous system during inflammation and/or ischemia.


CONCLUSIONS
The temporal and mechanistic overlap of the complement cascade with other biochemical events occurring in cerebral I/R injury is quite complex and is only beginning to be understood. However, there is compelling evidence that complement is quite active in the setting of acute stroke, suggesting that anticomplement strategies should be further investigated through genetic analysis, nonhuman primate models, and clinical investigations.
D'Ambrosio
A L
AL
Columbia University Department of Neurological Surgery, The Neurological Institute, New York, New York 10032, USA.
Pinsky
D J
DJ
Connolly
E S
ES
D000818:Animals; D002545:Brain Ischemia / Q000188:drug therapy / Q000276:immunology / Q000503:physiopathology*; D003167:Complement Activation; D003169:Complement Inactivator Proteins / Q000494:pharmacology* / Q000627:therapeutic use; D004195:Disease Models, Animal; D006801:Humans; D009474:Neurons / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D015427:Reperfusion Injury / Q000188:drug therapy / Q000276:immunology / Q000503:physiopathology*; D020521:Stroke / Q000188:drug therapy / Q000276:immunology / Q000503:physiopathology*
D003169:Complement Inactivator Proteins; D018696:Neuroprotective Agents