Antitrypanosomal potential of Salvia officinalis terpenoids-rich fraction in Trypanosoma evansi-infected rat model

Abstract Background Trypanosoma evansi (T. evansi) is a major protozoan disease that affects animals, including camels, and causes substantial economic detriments. The failure to control T. evansi infections is due to the unavailability of vaccines and the development of resistance to existing chemical drugs. In this study, we evaluated the effect of Salvia officinalis terpenoids-rich fraction on the degree of parasitemia and associated pathological alterations in rats experimentally infected with T. evansi. Method Eighty adult male rats were equally divided into 4 groups. The first group was a negative control. The second group was intraperitoneally infected with T. evansi at a dose of 1 × 104 trypanosomes. The third group was similarly infected and subsequently treated intramuscularly with diminazene aceturate at a dose of 7 mg/kg body weight (b.wt.). The fourth group received a daily oral administration of Salvia officinalis terpenoids-rich fraction at a dose of 300 mg/kg b.wt. throughout the experimental period and was also infected with T. evansi. Result The infection with T. evansi resulted in normocytic normochromic anemia, leukocytosis, hypoglycemia, hypertriglyceridemia, an increase in very low-density lipoprotein (VLDL) cholesterol, and reductions in high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterols. Additionally, the infection induced upregulation of the pro-inflammatory cytokines such as interleukin-1beta (IL-1β) and interleukin-6 (IL-6), and downregulation of the anti-inflammatory cytokines such as interleukin-10 (IL-10) and transforming growth factor beta (TGF-β). Besides histopathological changes in the brain and spleen, T. evansi markedly elevated brain oxidative stress and acetylcholinesterase (AChE) activity. The treatment with salvia fraction significantly decreased the degree of parasitemia and mitigated the T. evansi–induced pathological alterations. Conclusion The terpenoids-rich fraction from Salvia officinalis exhibits antitrypanosomal activity and may serve as a promising candidate for developing novel trypanocidal agents.