Fructose-1,6-diphosphate alone and in combination with cyclosporine potentiates rat cardiac allograft survival and inhibits lymphocyte proliferation and interleukin-2 expression.

Background Fructose-1,6-diphosphate (FDP) reduces postischemic reperfusion injury and is used alone and in combination with cyclosporine A (CsA) as an immunosuppressant. Methods. Wistar-Furth rat hearts were grafted to Lewis rats. Activated T-cell proliferation, viability, and interleukin-2 expression were determined. Results. Mean survival in days were: saline 7.12±0.64, FDP 350 mg/kg perioperatively 13.5±1.4, FDP 350 mg/kg twice daily 11.4±0.75, CsA 2.5 mg/kg daily 12±0.81, CsA 5.0 mg/kg daily 12.4±0.81, CsA 2.5 mg/kg + FDP 350 mg/kg twice daily 17.6±0.4, and CsA 5 mg/kg + FDP 350 mg/kg twice daily 28.2±0.97. FDP maximally inhibits T-cell proliferation and concomitantly increases cell viability at 5,000 to 500 μg/mL, whereas CsA inhibits at 500 ng/mL. FDP completely inhibited interleukin-2 expression at 5,000 to 500 μg/ mL, whereas CsA partially inhibited at 50 to 500 ng/mL. Conclusion. FDP + CsA prolongs cardiac survival and FDP inhibits T-cell proliferation.