Effect of microtubule-disrupting agents on superoxide production in human polymorphonuclear leukocytes

We explored the effects of compounds known or proposed to affect microtubule functions on superoxide (O2-) production in human polymorphonuclear leukocytes stimulated by N-formyl-methionyl-phenylalanine (f-Met-Phe), calcium ionophore A23187 and phorbol myristate acetate. F-Met-Phe-induced O2- production was markedly potentiated not only by microtubule-disrupting agents, including colchicine, vincristine, vinblastine, nocodazole, podophyllotoxin and griseofulvin, but also deuterium oxide (2H2O), which is proposed to stabilize microtubules, and not affected by lumicolchicine. Ionophore A23187-induced O2- production was not influenced by colchicine, and markedly enhanced by 2H2O, whereas phorbol myristate acetate-induced O2- production was not influenced by colchicine, and slightly inhibited by 2H2O. 2H2O did not counteract the effects of colchicine and vice versa. Dibutyryl cyclic AMP and prostaglandin E1 inhibited O2- production stimulated by f-Met-Phe and ionophore A23187, whereas phorbol myristate acetate-induced O2- production was strongly resistant to the inhibitory effect of these agents. The enhancing effect of colchicine and 2H2O on f-Met-Phe-induced O2- production was abolished by dibutyryl cyclic AMP. Colchicine promoted concanavalin A cap formation, and 2H2O produced concanavalin A patch formation, whereas dibutyryl cyclic AMP did not affect the distribution of concanavalin A receptors. In addition, 2H2O and dibutyryl cyclic AMP did not interfere with the colchicine-induced concanavalin A cap formation. These findings suggest that f-Met-Phe, ionophore A23187 and phorbol myristate acetate may activate the oxidative metabolism of human polymorphonuclear leukocytes through different mechanisms, and that microtubule-disrupting agents, 2H2O and cyclic AMP agonists may affect the different steps of the activating system of NAD(P)H oxidase.