Impact of nitric oxide precursor L-arginine on oxidative stress against typhoid

Typhoid fever is a global health problem caused by Salmonella. Salmonellae are gram-negative, flagellate, nonsporulating, facultative anaerobic bacilli that ferment glucose, reduce nitrate to nitrite, and synthesize peritrichous flagella when motile. Nowadays, most of the drugs are resistant, the fact of which compels the search for formulated drugs. Nitric oxide (NO) and its congeners react with different compounds or radicals probably mediating the broad-spectrum antimicrobial activity of reactive nitrogen species (RNS) as well as reactive oxygen species (ROS) against diverse microorganisms. Exogenous administration of L-arginine results in increased NO production. The formulation of NO precursors, (i.e. of L -arginine and ciprofloxacin) is used against experimentally induced salmonellosis. Lipid hydroperoxide can be decomposed to produce alkoxy and peroxy radicals which eventually yield numerous carbonyl products such as malondialdehyde (MDA).

Estimation of lipid peroxidation (LPO) was done by modified method of Utley et al (1967).

Infection with S. typhimurium significantly induced lipid peroxidation on days 8 and 11 as indicated by enhancement of MDA levels compared to the control mice (20 % and 9.52 %) (Tab. 1, Fig. 2, Ref. 20).