Oral Administration of Fumonisin B and T-2 Individually and in Combination Affects Hepatic Total and Mitochondrial Membrane Lipid Profile of Rabbits

Weaned rabbits were fed diets contaminated with 2 mg/kg diet T-2 toxin alone, or 10 mg/kg diet fumonisin B (FB) alone, and both toxins in combination (2 + 10 mg/kg, respectively) compared to a toxin-free control diet. Samplings were performed after 4 weeks (blood and liver). Bodyweight of T-2-fed group was lower after 4 weeks; the liver weight was increased dramatically (threefold of control). Liver total phospholipids (PLs) provided slight alterations in the fatty acid (FA) composition; all three toxin-treated groups showed a decrease in palmitoleic acid (C16:1 n7) proportion. In the liver mitochondrial PL FA composition, margaric acid (C17:0) proportion decreased in the separated toxin treatments compared to the combined setting. Oleic acid (C18:1 n9) proportion was increased and arachidonic acid (C20:4 n6) was decreased in the FB-treated group, while docosapentaenoic acid (C22:5 n3) was decreased in the separated treatments. The total monounsaturation was significantly higher in the FB group's mitochondrial PL FA profile. After 4 weeks, all toxin treatments decreased the blood plasma reduced glutathione and glutathione peroxidase activity, and FB increased the plasma sphinganine/sphingosine ratio. Both mycotoxins seem to cross the hepatocellular and the hepatic mitochondrial membrane, without drastic membrane disruption, as assessed from the PL FA composition, but inducing detectable lipid peroxidation.