Oxidative Stress as a Possible Target in the Treatment of Toxoplasmosis: Perspectives and Ambiguities

Abstract

Toxoplasma gondii is an apicomplexan parasite causing toxoplasmosis, a common disease, which is most typically asymptomatic. However, toxoplasmosis can be severe and even fatal in immunocompromised patients and fetuses. Available treatment options are limited, so there is a strong impetus to develop novel therapeutics. This review focuses on the role of oxidative stress in the pathophysiology and treatment of T. gondii infection. Chemical compounds that modify redox status can reduce the parasite viability and thus be potential anti-Toxoplasma drugs. On the other hand, oxidative stress caused by the activation of the inflammatory response may have some deleterious consequences in host cells. In this respect, the potential use of natural antioxidants is worth considering, including melatonin and some vitamins, as possible novel anti-Toxoplasma therapeutics. Results of in vitro and animal studies are promising. However, supplementation with some antioxidants was found to promote the increase in parasitemia, and the disease was then characterized by a milder course. Undoubtedly, research in this area may have a significant impact on the future prospects of toxoplasmosis therapy.

Histopathological, Immunohistochemical and Biochemical Studies of Murine Hepatosplenic Tissues Affected by Chronic Toxoplasmosis

“…The role of this enzyme in toxoplasmosis was evident by increased parasite burdens in infected mice administered iNOS inhibitor aminoguanidine and increased susceptibility to toxoplasmosis in iNOS-deficient mice during the late phase of infection [ 16 ]. Increased NO level during toxoplasmosis is pathognomonic, which is generated to control the disease [ 108 ]. However, all strains of toxoplasmosis adopted an evading strategy to escape NO harmful effect.…”

“…In the present work, a significant rise of nitric oxide level has been recorded in liver homogenate of a chronically infected group of mice sacrificed 9 wpi compared with the non-infected control subjects. This result is not surprising since Toxoplasma infection is known to induce oxidative stress in the liver of infected hosts [ 108 ]. This stressful condition is a state of imbalance between the production of reactive oxygen species (ROS) by the infected host and the antioxidant system of the invading organism [ 110 ].…”

Therapeutic potential of royal jelly to control Toxoplasma gondii infection in mice

“…LPO is recognized as an oxidative stress marker that, when elevated, can cause some biological damage such as destruction of cell membranes and release of hepatotoxicity indicator enzymes (Niki et al, 2005). During the T. gondii infection, mainly in the primary phase of diseases, tissue damage can occur due to the rise in the production of free radicals (Szewczyk-Golec et al, 2021). Here, we reported that the treatment of infected mice with RJ at the doses of 200, 400, and 600 mg/kg resulted in a significant reduction in the levels of LPO and NO (p < 0.01) whereas a significant increase (p < 0.05) in the amount of GPx and SOD was observed.…”

The Antioxidant Effect of Natural Antimicrobials in Shrimp Primary Intestinal Cells Infected with Nematopsis messor

“…An example of such damage was described in the case of Trichomonas vaginalis infections with significant impact on cellular trans-epithelial resistance (TEER) [11]. Following infection, parasites will trigger the host NADPH oxidases to produce and release reactive oxygen species (ROS); however, eukaryotic cells are equipped with molecular mechanisms required to reduce the damaging effects of oxidation [12]. They will activate the defensive enzymes, including superoxide dismutase (SOD) [13] or catalases (CAT), to counteract the damaging effects of the oxidative burst.…”