Biological effects of CDP-choline loaded long circulating liposomes on rat cerebral post-ischemic reperfusion

CDP-choline (CDPc) was encapsulated in unilamellar long circulating liposomes to improve biological effectiveness. The liposomal colloidal suspension was prepared by extrusion of multilamellar vesicles through polycarbonate filters. Unilamellar liposomes with a mean size of 50 nm and a polydispersity index of 0.01 were obtained. CDPc encapsulation capacity was 28 ml/mmol. Unilamellar liposome suspension presented a certain stability both in phosphate buffer and in serum, 25% of CDPc was released after 24 h. The colloidal properties and the presence of ganglioside G(M1) in liposome composition ensured a long-circulation of the carrier after i.v. administration. The therapeutic effects of CDPc-loaded unilamellar liposomes compared to the free drug were evaluated by an experimental model of ischemia and reperfusion, performed with Wistar rats (320-350 g). The liposomal formulation improved the survival rate of rats subjected to ischemia and reperfusion by approximately 66%, compared to free CDPc. A clinical application may be proposed.