Plasmodium-Salmonella Co-Infection Induces Intense Inflammatory Responsanirban Pal, Phd, Cisr-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh Indiae, Oxidative Stress and Liver Damage: A Mice Model Study for Therapeutic Strategy

Impairment of host immune response in malaria favours bacteraemia caused by typhoidal or non-typhoidal serovars of Salmonella enterica. Ofloxacin and Artesunate are the drugs that are clinically proven for treating typhoid and malaria respectively. The study evaluates the host responses upon treatment with antibiotic (Ofloxacin) and anti-malarial (Artesunate) in a standardized mice model harbouring co-infection. BALB/c mice (18-22 gm) were simultaneously co-infected with Plasmodium yoelii nigeriensis (Pyn) and Salmonella enterica Serovar Typhimurium (STm) and then treated with Ofloxacin or/and Artesunate from day 4 to day 7. The bacterial burden, Liver function enzymes, oxidative stress, m-RNA expression of Toll Like Receptors (TLR-2 and TLR-4), Th1/Th2 cytokines, Heme Oxygenase -1 and NFкB were assessed. Ofloxacin treatment failed to counter the bacterial proliferation in Pyn-STm co-infected mice. However, upon controlling parasitemia with anti-malarial, the efficacy of Ofloxacin could be regained. Elevated bacterial burden with malaria induces the expression of TLR-2 and TLR-4 triggering intense inflammatory response (NFκB, Th1/Th2 cytokines) in co-infected mice. This results in critical liver damage (ALT, AST and ALP), oxidative stress (Lipid peroxidation, Total GSH, Catalase and Super oxide dismutase) and Heme-oxygenase-1 (HO-1). The study concludes that malaria infection aggravates the secondary infection of Salmonella serovars and the control of septicaemia is critical in recovery of the co-infected subject.