Alteration of Multiple Cell Membrane Functions in L-6 Myoblasts by T-2 Toxin: An Important Mechanism of Action

摘要

Recent studies suggest that T-2 toxin interacts with cell membranes and alters membrane function. This study was done to assess the effect of T-2 toxin on a broad range of cell membrane functions in L-6 myoblasts. The following parameters were assessed after exposure to T-2 toxin for 10 min: the uptake of calcium,rubidium, and glucose; the uptake of leucine and tyrosine and incorporation into protein; the uptake of thymidine and incorporation into DNA; and residual cellular lactate dehydrogenase (LDH) as a measure of cell membrane integrity. The effects of T-2 toxin on these parameters were: the minimal effective concentration (MEC) of T-2 toxin that caused a reduction in uptake of calcium and glucose was 4 pg/ml. The MEC for reduction of uptake of leucine and tyrosine and their incorporation into protein was 4 pg/ml. Thymidine uptake and incorporation into DNA showed a biphasic response with an increase at 0.4 pg/ml and a reduction at 4 pg for uptake and 40 pg/ml for incorporation. (4) Intracellular LDH was reduced at 4 ng/ml. (5) Calcium efflux was reduced after 1-, 5-, adn 15-min exposure to T-2 toxin in a concentration of 40 ng/ml. T-2 toxin appears to have multiple effects on cell membrane function including effects on amino acid, nucleotide, and glucose transporters, as well as calcium and potassium (rubidium) channel activities.