Phosphatidylserine-containing liposomes promote maximal survival of retinal neurons after ischemic injury

We investigated the systemic effect of liposomes bearing apoptotic signals on the level of inflammation and neuronal death induced by ischemia-reperfusion (IR). Using a model of retinal ischemia, we showed that treatment with phosphatidylserine (PS) and phosphatidylcholine (PC) liposomes significantly reduced the expression of proinflammatory genes, including that of Il1b, Il6, Ccl2, Ccl5, Cxcl10, and Icam1, 24 h after reperfusion. Phosphatidylserine liposome treatment was the most efficient and correlated with significantly reduced neuronal death in the retina 7 days after reperfusion. The results of our study indicate that therapeutic strategy based on mimicking a systemic increase in apoptotic signaling can significantly reduce central nervous system damage induced by IR and improve neurologic outcome. Journal of Cerebral Blood Flow & Metabolism (2009) 29, 1755-1759; doi:10.1038/jcbfm.2009.95; published online 15 July 2009