Effects of polyamines on two strains of Trypanosoma brucei in infected rats and in vitro culture.
We studied the effects of polyamines, which are necessary for proliferation and antioxidation in Trypanosoma brucei gambiense Wellcome strain (WS) and Trypanosoma brucei brucei ILtat 1.4 strain (IL). No difference was found in activity of ornithine decarboxylase (ODC), a key enzyme in polyamine synthesis in trypanosomes, in both strains maintained in vitro; higher (P < 0.05) ODC values were found in IL in vivo. However, WS in vivo exhibited higher proliferation rates with higher spermidine content and decreased host survival times than IL. The in vitro proliferation and polyamine contents of WS increased with the addition of polyamine to the 1-difluoromethylornithine culture medium, but not IL. These results suggested that WS uses extracellular polyamine for proliferation. In the in vitro culture, WS was less tolerant of hydrogen peroxide (oxidative stress) than IL, and malondialdehyde levels in WS were higher than in IL. The expression of trypanothione synthetase mRNA in WS in vitro was higher than in IL. These results suggest that IL is dependent on the synthesis of polyamines for proliferation and reduction of oxidative stress, whereas WS is dependent on the uptake of extracellular polyamines. A thorough understanding of the differences in the metabolic capabilities of various trypanosomes is important for the design of more effective medical treatments.
Nishimura
Kazuhiko
K
Course of Veterinary Science, Graduate School Life and Environmental Sciences, Osaka Prefecture University 1-1, Gakuencho, Sakai, Osaka 599-8531, Japan. nisimura@vet.osakafu-u.ac.jp
Yanase
Takako
T
Araki
Noriko
N
Ohnishi
Yoshihiro
Y
Kozaki
Shunji
S
Shima
Kensuke
K
Asakura
Masahiro
M
Samosomsuk
Worada
W
Yamasaki
Shinji
S
D019732:Amide Synthases / Q000235:genetics / Q000378:metabolism; D000818:Animals; D003470:Culture Media; D000518:Eflornithine / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D005978:Glutathione / Q000031:analogs & derivatives / Q000378:metabolism; D006400:Hematocrit; D006861:Hydrogen Peroxide / Q000378:metabolism; D008297:Male; D009247:NADH, NADPH Oxidoreductases / Q000235:genetics / Q000378:metabolism; D009955:Ornithine Decarboxylase / Q000235:genetics / Q000378:metabolism; D065108:Ornithine Decarboxylase Inhibitors; D018384:Oxidative Stress / Q000187:drug effects*; D011073:Polyamines / Q000378:metabolism / Q000494:pharmacology*; D011700:Putrescine / Q000097:blood; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013095:Spermidine / Q000031:analogs & derivatives / Q000032:analysis / Q000097:blood / Q000378:metabolism; D013096:Spermine / Q000097:blood; D014346:Trypanosoma brucei brucei / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D014353:Trypanosomiasis, African / Q000188:drug therapy / Q000469:parasitology*
D003470:Culture Media; D004791:Enzyme Inhibitors; D065108:Ornithine Decarboxylase Inhibitors; D011073:Polyamines; D012333:RNA, Messenger; D013096:Spermine; C044809:trypanothione; D006861:Hydrogen Peroxide; D009247:NADH, NADPH Oxidoreductases; C049608:trypanothione reductase; D009955:Ornithine Decarboxylase; D019732:Amide Synthases; C064407:trypanothione synthetase; D005978:Glutathione; D013095:Spermidine; D011700:Putrescine; D000518:Eflornithine