Effects of Individual Circulating FFAs on Plasma Oxylipin Levels: Implications for FFA Epoxide-diol Ratios as Indices of Soluble Epoxide Hydrolase Activity.

Raising plasma FFAs has profound effects to decrease plasma FFA epoxides, significantly altering plasma epoxide-diol ratios. These data suggest that caution should be taken in comparing epoxide-diol ratios, as indices of sEH activity, between conditions with different circulating FFA levels. Our data also suggest that plasma FFAs regulate epoxide levels by stimulating a metabolic process independent of sEH, possibly glucuronidation followed by renal excretion.