A metabolic flux analyis to quantify the hepatic metabolism during defatting

Macrosteatotic livers, with hepatocytes that have accumulated lipids in the form of large lipid droplets, have been shown to be at a significant risk for primary graft nonfunction due to increased sensitivity to ischemia reperfusion (I/R) injury in the transplantation process. Nearly 30% of donated livers are discarded annually due to their macrosteatotic state. Our lab has previously demonstrated that a cocktail of defatting agents can clear excess lipid storage in fatty livers, thus providing a new means to recondition donated livers that would otherwise be discarded. Currently, however, the process is highly rate-limited and therefore not yet translatable to the workflow of transplant surgeries. To identify reaction-rate limited metabolic pathways in the defatting process, a metabolic flux analysis (MFA) was conducted. The changes in metabolic reaction fluxes of macrosteatotic HepG2 hepatocytes undergoing defatting were elucidated. We hope the insights from the MFA will allow us to metabolically optimize hepatic function in the macrosteatotic state and potentially identify novel metabolic supplements for a more rapid defatting of marginal donor livers.