PTPA and Insulin resistance: Indeed, based on the previously reported observation that active PP2A can mediate palmitate-induced insulin resistance [30], it is plausible that the ability of the saturated fatty acid (or lipid intermediates derived from it, such as ceramide) to inhibit PKB/Akt may be mediated, at least in part, through promoting REDD1-dependent interactions between PP2A and PKB/Akt.