Polyamine uptake by a rodent filariid, Acanthocheilonema viteae (Nematoda: Filarioidea).

Helminth parasites lack the capacity to synthesize polyamines de novo. With the view to characterise alternative pools for the replenishment of polyamines, uptake of spermidine and spermine, were studied in Acanthocheilonema viteae, a parasite known to infect rodents. Motile worms recovered from the subcutaneous tissues of experimentally infected Mastomys natalensis were incubated in vitro with radiolabelled polyamines for the uptake assays. A time-dependent, temperature-sensitive, energy-requiring and saturable-uptake of the polyamines was observed. Male worms exhibited better uptake than the females and spermidine influx occurred at a higher rate than for spermine. A marginal competition of spermine with spermidine uptake and vice-versa was noticed while putrescine did not compete with uptake of either polyamines. Methyl-glyoxal-bis-guanyl hydrazone and Berenil caused significant inhibition of spermidine as well as spermine uptake. Subcutaneous tissues of A. viteae infected animals exhibited markedly higher levels of polyamines compared with the tissues obtained from healthy animals. Filarial worms are thus equipped with multiple polyamine transport systems which may aid their growth and survival within the host.