# Evaluation of the potential therapeutic efficacy of Cerastes cerastes venom in acute experimental toxoplasmosis

## TL;DR

This study explores the potential of Cerastes cerastes venom as a natural treatment for toxoplasmosis in mice, showing it significantly reduces parasite burden and is safe at low doses.

## Contribution

The first evaluation of Cerastes cerastes venom's anti-Toxoplasma efficacy in both immunocompetent and immunosuppressed mice.

## Key findings

- CCV treatment significantly reduced peritoneal and liver parasite burdens by over 88% in both immunocompetent and immunosuppressed mice.
- The venom caused ultrastructural changes in tachyzoites and showed high antioxidant activity with no significant toxicity.
- CCV increased survival time and reduced infectivity in peritoneal fluid and liver tissues.

## Abstract

The control of toxoplasmosis relies on conventional chemotherapeutics, which have hitherto unresolved concerns.

Swiss albino mice were intraperitoneally (IP) infected with 5 × 103 tachyzoites of RH HXGPRT( −) strain of Toxoplasma gondii, then IP treated with one-fourth lethal dose 50 (one-fourth LD50) of Cerastes cerastes venom (CCV) for three consecutive days (LD = 0.535 mg/kg). The anti-Toxoplasma activity of CCV was evaluated, for the first time, in immunocompetent (IC) and immunosuppressed (IS) mice via estimation of their mortality and survival time, microscopical counting of peritoneal tachyzoites, measurement of liver parasite burdens using quantitative real-time polymerase chain reaction (qRT–PCR), detection of infectivity, and ultrastructural changes of the treated tachyzoites. The safety of the used dose was biochemically assessed by measuring liver, kidney, and oxidative stress markers in serum.

CCV induced an insignificant reduction in mortality rate (MR) and a significant increase in survival time of mice. A statistically significant decrease in the mean peritoneal parasite burden with 89.8% and 90.8% reduction (%R) was observed in both IC and IS-treated subgroups compared with their controls, respectively. This reduction was consistent with 88% and 86% decrease in liver parasite load, respectively, and obvious ultrastructural alterations in treated tachyzoites. Concerning the infectivity study, the percent reduction was 78.8% and 85.5% in the peritoneal fluid and 71.1% and 60.4% in the liver tissues of IC and IS subgroups, respectively. The biochemical safety of the used dose and its high antioxidant activity were verified.

Thus, one-fourth LD50 of CCV can be considered a promising, effective natural alternative to standard chemotherapy for acute toxoplasmosis.

The online version contains supplementary material available at 10.1186/s13071-025-07209-9.