Fucoidan Cures Infection with both Antimony-Susceptible and -Resistant Strains of Leishmania Donovani through Th1 Response and Macrophage-Derived Oxidants
IR@IICB: CSIR-Indian Institute of Chemical Biology, KolkataView Archive Info
Fucoidan Cures Infection with both Antimony-Susceptible
and -Resistant Strains of Leishmania Donovani through Th1 Response and Macrophage-Derived Oxidants
Das, Pijush K
Infectious Diseases and Immunology
The aim of this study was to evaluate and characterize the antileishmanial efficacy of fucoidan, a
polyanionic sulphated polysaccharide from brown algae, in experimental infections of BALB/c mice with antimony-
susceptible (AG83) and -resistant (GE18ER) Leishmania donovani.
The effect of fucoidan was assessed against intracellular parasites in cultured macrophages and in
suppressing splenic and liver parasite burdens in a BALB/c mouse model of visceral leishmaniasis by microscopic
evaluation of surviving intracellular amastigotes stained with Giemsa. To evaluate the type of immunological
responses, real-time PCR and ELISA were performed for various Th1 and Th2 cytokines in both in vitro
and in vivo infected conditions. To determine the effector mechanism, reactive oxygen species (ROS) and NO
were measured in fucoidan-treated animals by H2DCFDA-based fluorometric analysis and Griess reaction,
In addition to having appreciable inhibitory effect on amastigote multiplication within macrophages
(.93% inhibition at 50 mg/mL), complete elimination of liver and spleen parasite burden was achieved by fucoidan
at a dose of 200 mg/kg/day given orally, 3 times weekly, in a 6-week mouse model of both antimony-susceptible
and -resistant strains. This curative effect is associated with switching of T cell differentiation from Th2
to Th1 mode. Further, splenocytes of fucoidan-treated infected (AG83 and GE18FR) mice generated significantly
enhanced levels of superoxide and NO. Not only was this treatment curative when administered
orally 15 days post-infection, but it also imparted resistance to reinfection. These results suggest the effectiveness of fucoidan as potent immunomodulator for controlling
both antimony-susceptible and -resistant visceral leishmaniasis.
Kar, Susanta and Sharma, Gunjan and Das, Pijush K (2011) Fucoidan Cures Infection with both Antimony-Susceptible and -Resistant Strains of Leishmania Donovani through Th1 Response and Macrophage-Derived Oxidants. Journal of Antimicrobial Chemotherapy, 66. pp. 618-625.