Toxoplasma Reduces Complications of Parkinson's Disease: An Experimental Study in BALB/c Mice.

Background: Parkinson's disease (PD) has been described in dopamine brain level reductions. Conversely, several studies have shown that Toxoplasma parasite can increase the level of dopamine in an infected host. This study was conducted to assess the serum, cerebral dopamine levels, and downregulation of Parkinson's disease manifestations in mice with chronic toxoplasmosis. Methods: PD induction was done by oral inoculation of rotenone into BALB/c mice. To induce the chronic infection, cysts of T. gondii Prugniaud strain (genotype II) were injected intraperitoneally into the mice. The rotarod test was used for the evaluation of functional motor disorders in experimental mice. The serum and cerebral dopamine levels of the mice were also measured by using high-performance liquid chromatography (HPLC) on consecutive periods (10 days). Results: Findings of the rotarod test showed the highest and lowest average of running duration belonged to the uninfected mice and PD mice, respectively. Remarkably, the running duration of infected mice with PD was higher than PD mice. As well, the level of serum and cerebral dopamine increased in mice with PD and toxoplasmosis in comparison with PD mice. Conclusion: Increasing the serum and cerebral dopamine levels in mice infected with toxoplasmosis is related to the presence of the parasite. Moreover, the dopamine upregulation due to the infection is effective in the reduction of PD complications.

In vivo and in vitro evaluation of the effect of glyphosate (Roundup) on Toxoplasma gondii.

Apicoplast, a derived non-photosynthetic plastid, which is found in most Apicomplexa, provides essential functions to parasites. The shikimate pathway is localized in the plant chloroplast as a remarkable route for the survival of the Toxoplasma. In this study, in vivo and in vitro effects of glyphosate (Roundup, Herbicide), as an inhibitor of the enzyme, were evaluated on T. gondii. Tachyzoites of RH strain were incubated for 1.5 h in various concentrations (1-128 µg/ml) of glyphosate. The parasite was cultivated in the cell monolayer of the heLa cell, and then the cultures were exposed to various concentrations. To evaluate the therapeutic quality, 2 × 105 tachyzoites were intradermally inoculated into ten mice from each group. Four doses of the compound were daily administrated every 24 h after inoculation due 10 days continuously. Also, two other groups were assigned as the positive and negative control. In flow cytometry, the highest mortality rate was related to concentrations of 128 and 256 µg/ml, 18.29% and 18.64%, respectively, while the mortality rate was 0.03% in the negative control (P value > 0.05). Based on microscopic observation of the stained touch smear of the liver, all treated mice were killed by the parasite. This compound also had no lethal effect on the mice. According to the results of this study, glyphosate is not a good candidate for the treatment of toxoplasmosis. It seems that the parasite has another pathway for providing the essential amino acids.

Evaluation of the Tyrosine and Dopamine Serum Levels in Experimental Infected BALB/c Mice with Chronic Toxoplasmosis.

BACKGROUND: Toxoplasma parasite alters the transduction of neurotransmitter signals and leads to changes in the level of brain neurotransmitters including tyrosine and dopamine, so behavior changes can occur in infected hosts. Based on this concept, this study was conducted for evaluation of the tyrosine and dopamine serum levels in infected mice with chronic toxoplasmosis. MATERIALS AND METHODS: Toxoplasma gondii (Prugniaud strain II) was injected intraperitoneally into BALB/c mice to induce chronic toxoplasmosis. Modified agglutination test (MAT), polymerase chain reaction (PCR), and microscopic methods were conducted to confirm the induction of chronic toxoplasmosis. The infected mouse sera were separated at days 40, 50, 60, 70, and 80 for evaluation of tyrosine and dopamine serum levels using high-performance liquid chromatography (HPLC). RESULTS: Microscopic methods confirmed the formation of the Toxoplasma cysts in mouse tissues. Inducing chronic toxoplasmosis is also confirmed by MAT, PCR, and histological methods. HPLC results indicated a decrease in serum tyrosine level at day 40 in infected mice in comparison to control, and the levels were too low to be measured at other times. However, a significantly high serum dopamine level was observed that gradually increased after parasite inoculation. CONCLUSIONS: No detection of tyrosine level in most of the sample groups is probably related to the very low concentration of tyrosine in sera. However, low concentration of tyrosine at day 40 and increase of dopamine in most of the sample groups suggest the production of dopamine from tyrosine due to the presence of Toxoplasma in infected mice.

Introduction of protocols for mass production of Toxoplasma gondii tachyzoites of the genotype II PRU strain.

Background: Few investigations of genotype II of Toxoplasma gondii, the most prevalent form of the Toxoplasma parasite in humans, have been carried out on due to the rapid conversion of tachyzoites to bradyzoites in its life cycle. The current study aimed to create animal and in vitro models for production of the tachyzoites of the Prugniaud (PRU) genotype II strain. Methods: To develop an immunocompromised model and obtain tachyzoites of the PRU strain, BALB/c mice were orally treated with dexamethasone (10 mg/kg), cyclophosphamide (36 mg/kg), and cyclosporine (18 mg/kg) from 5 days prior to inoculation. Then, 10-15 tissue cysts of PRU strain were inoculated intraperitoneally into the mice. The tachyzoites obtained from mice were then cultivated in a HeLa cell culture. The resulting yield of tachyzoites was cryopreserved in 92% fetal calf serum, 8% dimethyl sulfoxide. The infectivity of these tachyzoites was evaluated using in vivo and in vitro examinations. Results: Numerous tachyzoites were observed in the peritoneal fluid of the immunosuppressed mice within 10-15 days after inoculation, and many tachyzoites were harvested from the HeLa cell culture. Trypan Blue staining showed 80% viability of the tachyzoites recovered from cryopreservation and this was confirmed by HeLa cell culture. In addition, mice infected intraperitoneally with the recovered tachyzoites presented with cysts in the brain after 2 months. Conclusion: We have developed an animal model for mass production of T. gondii tachyzoites of the PRU strain. This method can provide fresh viable tachyzoites of Toxoplasma gondii for use as and when required in future investigations.

Cutaneous leishmaniasis associated with Systemic Lupus Erythematosus (SLE).

Cutaneous Leishmaniasis (CL) is a protozoan disease caused by Leishmania spp. and is endemic in the Americas, the Mediterranean basin, Middle East, and Central Asia. There are reports regarding the co-infection of CL with other diseases, especially immune system disorders. Herein, we presented a patient with several leishmania lesions who suffered from Systemic Lupus Erythematosus (SLE). He was a 22-year-old man from Fars province, southern Iran who was treated with corticosteroid drugs to control the manifestations of SLE. The presence of leishmanial bodies was confirmed by microscopic and molecular methods. Treatment was performed based on sodium antimony gluconate (1.5 mg/5ml) for three weeks, resulting in acceptable outcomes. However, recurrence of the lesions was observed after two months when the medication was discontinued. This was the first report of Zoonotic Cutaneous Leishmaniasis (ZCL) in an SLE patient.