Antimalarial effect of agmatine on Plasmodium berghei K173 strain.
OBJECTIVE
To study the antimalarial effect of agmatine (Agm) on chloroquine-susceptible Plasmodium berghei K173 strain (S strain) and the P berghei K173 resistant strain (R strain).


METHODS
The antimalarial effects of Agm on P berghei K173 S strain and R strain were evaluated by Peters 4-d suppression test in mice.


RESULTS
Agm (12.5-200 mg/kg, ig, daily) decreased the parasitemia for both P berghei K173 S strain (IC(50)=139 mg/kg) and R strain (IC(50)=126 mg/kg) in mice. Subcutaneous injection (sc) of Agm (5-40 mg/kg, tid) showed relatively stronger antimalarial effect than intragastric gavage (IC(50)=30 mg/kg ) in P berghei K173 S strain. Spermidine antagonized the antimalarial effect of Agm for P berghei K173 S strain and R strain. Agm did not reverse the chloroquine resistance of P berghei K173 S strain. dl-alpha-Difluoromethylornithine (DFMO, sc) decreased the parasitemia of P Berghei K173 S strain and this effect was antagonized by spermidine.


CONCLUSIONS
Agm has an antimalarial effect and the mechanism is related to its inhibition of polyamine synthesis.
Su
Rui-Bin
RB
Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China. Ruibinsu@yahoo.com
Wei
Xiao-Li
XL
Liu
Yin
Y
Li
Jin
J
D000376:Agmatine / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D000962:Antimalarials / Q000494:pharmacology* / Q000627:therapeutic use; D002738:Chloroquine / Q000494:pharmacology; D004195:Disease Models, Animal; D004351:Drug Resistance; D000518:Eflornithine / Q000494:pharmacology; D005260:Female; D008288:Malaria / Q000188:drug therapy*; D008297:Male; D051379:Mice; D065108:Ornithine Decarboxylase Inhibitors; D018512:Parasitemia / Q000188:drug therapy; D021261:Parasitic Sensitivity Tests; D010962:Plasmodium berghei / Q000187:drug effects*
D000962:Antimalarials; D065108:Ornithine Decarboxylase Inhibitors; D000376:Agmatine; D002738:Chloroquine; D000518:Eflornithine