Pyruvate Protects Giardia Trophozoites from Cysteine-Ascorbate Deprived Medium Induced Cytotoxicity
- Author:
Dibyendu RAJ
1
;
Punam CHOWDHURY
;
Rituparna SARKAR
;
Yumiko SAITO-NAKANO
;
Keinosuke OKAMOTO
;
Shanta DUTTA
;
Tomoyoshi NOZAKI
;
Sandipan GANGULY
Author Information
- Publication Type:Original Article
- Keywords: Giardia lamblia; oxidative stress; cysteine-ascorbate; antioxidant; pyruvate; reactive oxygen species; cytotoxicity
- MeSH: Child; Culture Media; DNA Breaks; DNA Damage; DNA Repair; Giardia lamblia; Giardia; Giardiasis; Humans; Metabolism; Oxidative Stress; Parasites; Pyruvic Acid; Reactive Oxygen Species; Trophozoites; Young Adult
- From:The Korean Journal of Parasitology 2018;56(1):1-9
- CountryRepublic of Korea
- Language:English
- Abstract: Giardia lamblia, an anaerobic, amitochondriate protozoan parasite causes parasitic infection giardiasis in children and young adults. It produces pyruvate, a major metabolic product for its fermentative metabolism. The current study was undertaken to explore the effects of pyruvate as a physiological antioxidant during oxidative stress in Giardia by cysteine-ascorbate deprivation and further investigation upon the hypothesis that oxidative stress due to metabolism was the reason behind the cytotoxicity. We have estimated intracellular reactive oxygen species generation due to cysteine-ascorbate deprivation in Giardia. In the present study, we have examined the effects of extracellular addition of pyruvate, during oxidative stress generated from cysteine-ascorbate deprivation in culture media on DNA damage in Giardia. The intracellular pyruvate concentrations at several time points were measured in the trophozoites during stress. Trophozoites viability under cysteine-ascorbate deprived (CAD) medium in presence and absence of extracellular pyruvate has also been measured. The exogenous addition of a physiologically relevant concentration of pyruvate to trophozoites suspension was shown to attenuate the rate of ROS generation. We have demonstrated that Giardia protects itself from destructive consequences of ROS by maintaining the intracellular pyruvate concentration. Pyruvate recovers Giardia trophozoites from oxidative stress by decreasing the number of DNA breaks that might favor DNA repair.
