IGL-1 preservation solution protects rat liver against apoptosis in orthotopic liver transplantation

Background: Injury due to cold ischemia reperfusion (I/R) is a major cause of graft non-function following liver transplantation and the use of an appropriate preservation solution is crucial for the viability of liver grafts. Glycogen synthase kinase-3b (GSK3b) phosphorylates voltage-dependent anion channel (VDAC), the most abundant protein in the outer membrane of mitochondria, and this in turn increases cell death during the ischemic insult. Thus, the inhibition of GSK3b activity is crucial for mitochondrial protection and the subsequent suppression of apoptosis. In this communication, we investigated the involvement of GSK3b in livers subjected to orthotopic liver transplantation (OLT) when IGL-1 preservation solution was used. Methods: Male Sprague Dawley (200-250 g.b.w.) rats were classified as follows: Group1 = Sham; Group2 (UW) = Livers were flushed and preserved in UW for 8 h at 4°C and subjected to OLT. Rats were sacrificed at 24 h after transplantation according to Kamada 's cuff technique; Group 3 (IGL-1) = Livers were flushed and preserved in IGL-1 for 8 h at 4°C and subjected to OLT. Rats were sacrificed at 24 h after transplantation and then blood and liver samples were collected.ALT/AST, AMPK, PI3K/AKT and their direct substrate, GSK3-b and pVDAC were determined by Western blot. Mitochondrial injury (GLDH) and oxidative stress (MDA) were measured. Measure of apoptosis parameters was also performed. Results: (i) IGL-1 significantly reduced liver injury (AST/ ALT) and mitochondrial damage when compared to UW. This graft protection was accompanied by increased AKT phosphorylation and subsequent GSK3-b inhibition, (ii) A significant reduction in pVDAC and release of Cytochrome C and caspases levels were found. Conclusion: IGL-1 preservation solution increases the tolerance of the liver graft against IRI through inhibition of GSK3b, preventing thus liver apoptosis.