Biochemistry Insights

In the current study, we used immunoprecipitation and immunoblotting to examine the levels and phosphorylation status of the insulin receptor-beta subunit (IR-β), as well as the down stream target in PI3K pathway, total PKB/Akt as well as their phosphorylated forms. The assessment of FFAs treatment showed no direct and significant effect on the PI3K stimulation, specifically the IR-β in primary hepatic control cells treated with insulin. Cells treated with either oleate or palmitate (360 µM) showed no statistically significant values following insulin stimulation (P > 0.05). To further investigate the effect of both FFAs and high insulin (1 µg), we examined the effects of oleate and palmitate at 360 µM concentration on IR-β as well as PKB. There was no significant difference in the total protein levels and their phosphorylated forms in cells treated with or without oleate or plamitate. Interestingly, IR-β tyrosine phosphorylation showed a similar insignificant effect in vivo and ex vivo hepatic cells treated with oleate or palmitate in comparison to their controls in the fructose fed hamsters.