Previous Article | Next Article ![]()
Antimicrobial Agents and Chemotherapy, May 2006, p. 1788-1797, Vol. 50, No. 5
0066-4804/06/$08.00+0 doi:10.1128/AAC.50.5.1788-1797.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.
Department of Immunology, Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, India,1 Department of Crystallography and Molecular Biology, Saha Institute of Nuclear Physics, Kolkata 700064, India,2 Department of Environmental Carcinogenesis and Toxicology, Chittaranjan National Cancer Institute, Kolkata 700026, India,3 National Centre for Cell Science, Pune 411007, India,4 Department of Cell Biology and Immunology, Institute of Microbial Technology, Chandigarh 160036, India5
Received 23 December 2005/ Returned for modification 7 February 2006/ Accepted 27 February 2006
Pentavalent antimony complexes, such as sodium stibogluconate and sodium antimony gluconate (SAG), are still the first choice for chemotherapy against various forms of leishmaniasis, including visceral leishmaniasis, or kala-azar. Although the requirement of a somewhat functional immune system for the antileishmanial action of antimony was reported previously, the cellular and molecular mechanism of action of SAG was not clear. Herein, we show that SAG induces extracellular signal-regulated kinase 1 (ERK-1) and ERK-2 phosphorylation through phosphoinositide 3-kinase (PI3K), protein kinase C, and Ras activation and p38 mitogen-activated protein kinase (MAPK) phosphorylation through PI3K and Akt activation. ERK-1 and ERK-2 activation results in an increase in the production of reactive oxygen species (ROS) 3 to 6 h after SAG treatment, while p38 MAPK activation and subsequent tumor necrosis factor alpha release result in the production of nitric oxide (NO) 24 h after SAG treatment. Thus, this study has provided the first evidence that SAG treatment induces activation of some important components of the intracellular signaling pathway, which results in an early wave of ROS-dependent parasite killing and a stronger late wave of NO-dependent parasite killing. This opens up the possibility of this metalloid chelate being used in the treatment of various diseases either alone or in combination with other drugs and vaccines.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»