Potential effects of alpha-pinene, a monoterpene commonly found in essential oils against Toxoplasma gondii infection; an in vitro and in vivo study

This survey designed to assess the in vitro and in vivo activity of α-pinene, a monoterpene commonly originated in essential oils on Toxoplasma gondii . The in vitro effect of various concentration of α-pinene against tachyzoites of T. gondii Rh strain was assessed by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The activity of α-pinene on the stimulation of apoptosis in tachyzoites of T. gondii was also examined using the caspase 3 colorimetric activity assay. In vivo assay, mice were orally received α-pinene at 2 and 4 mg/kg/day for 14 days, then, pre-treated mice were daily tested and the rate of death was recorded. α-pinene meaningfully declined ( p < 0.001) the tachyzoites viability with the IC 50 value of 23.3 µg/mL. α-pinene induced the apoptosis through increasing the caspase-3 activity by 35.6%. Oral treatment with α-pinene significantly ( p < 0.01) improved the survival rate infected mice with by 9th day. α-pinene + atovauone (50 mg/kg) significantly ( p < 0.01) improved the survival rate infected mice up to 11 days compared with the control groups. α-pinene especially in combined atovaquone at 50 mg/kg for 2 weeks meaningfully ( p < 0.05) declined oxidative stress. We found the promising in vitro anti- Toxoplasma effects of α-pinene on T. gondii RH strain. In addition, we found that α-pinene therapy particularly along with the reference drug declined the mortality rate of infected mice. Although, we just confirmed the stimulation of apoptosis and anti-inflammatory effects as the main anti- Toxoplasma mechanisms of α-pinene; however, more surveys concerning the accurate mechanisms, toxicity, and efficacy on other T. gondii strains are required to confirm these results.