Toxoplasmosis and anti-Toxoplasma effects of medicinal plant extracts-A mini-review

Copaifera spp. oleoresins and two isolated compounds (ent-kaurenoic and ent-polyalthic acid) inhibit Toxoplasma gondii growth in vitro

Toxoplasmosis affects about one-third of the world's population. The disease treatment methods pose several side effects and do not efficiently eliminate the parasite, making the search for new therapeutic approaches necessary. We aimed to assess the anti-Toxoplasma gondii activity of four Copaifera oleoresins (ORs) and two isolated diterpene acids, named ent-kaurenoic and ent-polyalthic acid. We used HeLa cells as an experimental model of toxoplasmosis. Uninfected and infected HeLa cells were submitted to the treatments, and the parasite intracellular proliferation, cytokine levels and ROS production were measured. Also, tachyzoites were pre-treated and the parasite invasion was determined. Finally, an in silico analysis was performed to identify potential parasite targets. Our data show that the non-cytotoxic concentrations of ORs and diterpene acids controlled the invasion and proliferation of T. gondii in HeLa cells, thus highlighting the possible direct action on parasites. In addition, some compounds tested controlled parasite proliferation in an irreversible manner. An additional and non-exclusive mechanism of action involves the modulation of host cell components, by affecting the upregulation of the IL-6. Additionally, molecular docking suggested that ent-polyalthic acid has a high affinity for the active site of the TgCDPK1 protein. Copaifera ORs have great antiparasitic activity against T. gondii, and this effect can be partially explained by the presence of the isolated compounds ent-kaurenoic and ent-polyalthic acid.

Ameliorative effects of propolis and wheat germ oil on acute toxoplasmosis in experimentally infected mice are associated with reduction in parasite burden and restoration of histopathological changes in the brain, uterus, and kidney

Toxoplasmosis continues to be a prevalent parasitic zoonosis with a global distribution. This disease is caused by an intracellular parasite known as Toxoplasma gondii, and the development of effective novel drug targets to combat it is imperative. There is limited information available on the potential advantages of wheat germ oil (WGO) and propolis, both individually and in combination, against the acute phase of toxoplasmosis. In this study, acute toxoplasmosis was induced in Swiss albino mice, followed by the treatment of infected animals with WGO and propolis, either separately or in combination. After 10 days of experimental infection and treatment, mice from all groups were sacrificed, and their brains, uteri, and kidneys were excised for histopathological assessment. Additionally, the average parasite load in the brain was determined through parasitological assessment, and quantification of the parasite was performed using Real-Time Polymerase Chain Reaction targeting gene amplification. Remarkably, the study found that treating infected animals with wheat germ oil and propolis significantly reduced the parasite load compared to the control group that was infected but not treated. Moreover, the group treated with a combination of wheat germ oil and propolis exhibited a markedly greater reduction in parasitic load compared to the other groups. Similarly, the combination treatment effectively restored the histopathological changes observed in the brain, uterus, and kidney, and the scoring of these reported lesions confirmed these findings. In summary, the present results reveal intriguing insights into the potential therapeutic benefits of wheat germ oil and propolis in the treatment of acute toxoplasmosis.

Potent In Vitro and In Vivo Effects of Stachys lavandulifolia Methanolic Extract against Toxoplasma gondii Infection

The present study aimed to evaluate the in vitro, in vivo, and safety of Stachys lavandulifolia Vahl. methanolic extract (SLME) against acute toxoplasmosis caused by Toxoplasma gondii RH strain in mice.

METHODS

MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was used to evaluate the in vitro effect of the SLME on T. gondii tachyzoites. Totally, 72 male BALB/c mice (40 mice for in vivo evaluation of SLME and 32 mice for its toxicity effects on liver and kidney serum enzymes) were used for the present investigation. At first, 40 mice were orally pre-treated with the SLME at doses of 25, 50, and 75 mg/kg/day for two weeks. Mice were checked daily, and the rate of survival and the mean number of tachyzoites were recorded. Liver lipid peroxidation (LPO) and nitric oxide (NO) levels, the effects on kidney and liver function, as well as the expression level of the proinflammatory cytokines such as interleukin-1β (IL-1β) and interferon-γ (IFN-γ), were studied by the quantitative real-time PCR. Flow cytometry analysis was performed on the effects of SLME on the detection of apoptotic and necrotic cells in T. gondii tachyzoites.

RESULTS

The SLME at the concentrations 75 and 150 µg/mL completely killed the tachyzoites after 2 hr of incubation. SLME at 25, 50, and 75 mg/kg/day increased the survival rate of infected mice by the sixth, seventh, and eighth days, respectively. SLME also significantly (p < 0.05) decreased the LPO and NO levels and upregulated the IL-1β and IFN-γ mRNA gene expression levels, whereas no considerable change was observed in the serum level of kidney and liver enzymes. Flow cytometry analysis revealed the prompted early and late apoptosis after exposure to T. gondii tachyzoites with various concentrations of SLME.

CONCLUSION

We found the relevant in vitro anti-Toxoplasma effects of SLME against T. gondii. Moreover, the results confirmed the promising in vivo prophylactic effects of SLME. SLME provokes the innate immune system, induces apoptosis, modulates the proinflammatory cytokines, and inhibits hepatic injury in infected mice. With all these descriptions, further surveys are required to support these findings and elucidate this plant's possible mechanisms of action.

Versatile anti-infective properties of pyrido- and dihydropyrido[2,3-d]pyrimidine-based compounds

A series of 1H-indeno[2',1':5,6]dihydropyrido[2,3-d]pyrimidine and 1H-indeno[2',1':5,6]pyrido[2,3-d]pyrimidine derivatives was prepared and screened for antiparasitic and viral RNase H inhibitory activity. Several compounds showed considerable activity against Toxoplasma gondii parasites and Leishmania major amastigotes, which warrants further investigation. Based on the structural similarities of certain derivatives with common viral RNase H inhibitors, a HIV-1 RNase H assay was used to study the RNase H inhibition by selected test compounds. Docking of active derivatives into the active site of the HIV-1 RNase H enzyme was carried out. The new compound 2a, inactive in the antiparasitic tests, showed distinct HIV-1 RNase H inhibition. Thus, ring substitution determines antiparasitic or HIV-1 RNase H inhibitory activity of this promising compound class.

Evaluation of the Antiparasitic and Antifungal Activities of Synthetic Piperlongumine-Type Cinnamide Derivatives: Booster Effect by Halogen Substituents

A series of synthetic N-acylpyrrolidone and -piperidone derivatives of the natural alkaloid piperlongumine were prepared and tested for their activities against Leishmania major and Toxoplasma gondii parasites. Replacement of one of the aryl meta-methoxy groups by halogens such as chlorine, bromine and iodine led to distinctly increased antiparasitic activities. For instance, the new bromo- and iodo-substituted compounds 3 b/c and 4 b/c showed strong activity against L. major promastigotes (IC50 =4.5-5.8 μM). Their activities against L. major amastigotes were moderate. In addition, the new compounds 3 b, 3 c, and 4 a-c exhibited high activity against T. gondii parasites (IC50 =2.0-3.5 μM) with considerable selectivities when taking their effects on non-malignant Vero cells into account. Notable antitrypanosomal activity against Trypanosoma brucei was also found for 4 b. Antifungal activity against Madurella mycetomatis was observed for compound 4 c at higher doses. Quantitative structure-activity relationship (QSAR) studies were carried out, and docking calculations of test compounds bound to tubulin revealed binding differences between the 2-pyrrolidone and 2-piperidone derivatives. Microtubules-destabilizing effects were observed for 4 b in T. b. brucei cells.

Diagnosis of Toxoplasmosis Using Surface Antigen Grade 1 Detection by ELISA, Nano-Gold ELISA, and PCR in Pregnant Women

Introduction

The accurate diagnosis of toxoplasmosis has critical importance in pregnant women. Nanotechnology and molecular biology are making possible opportunities for accurate and rapid diagnosis of many infectious diseases.

Aim and Methods

The aim of our study was to compare nano-gold ELISA with ELISA and PCR for diagnosis of toxoplasmosis using Toxoplasma surface antigen grade 1 (SAG1) in pregnant women seeking antenatal care in outpatient clinics.

Results

PCR showed the highest diagnostic values than nano-gold ELISA and ELISA regarding sensitivity (97.3% versus 89.2% and 83.8%); specificity (100% versus 94% and 88%); and diagnostic accuracy (98.9% versus 91.95% and 86.2%), respectively. There is no statistical difference between PCR and nanogold ELISA results.

Discussion

Nano-gold ELISA had a significant improvement in diagnosis than the traditional ELISA method. Most likely with the assistance of nanoparticles, more antibodies enter the antigen-antibody complex because of the considerable improvement in the surface area of nano-gold particles.

Conclusion

Although PCR had higher diagnostic values than nano ELISA, nano ELISA is cheaper and easier than PCR. We recommend nano-gold ELISA with SAG1 as a promising technique in the diagnosis of toxoplasmosis and survey studies.

Anti-Toxoplasma Effects of Dracocephalum Polychaetum Essential Oil

Background

Toxoplasma gondii is a common parasitic disease with a cosmopolitan prevalence, causing severe health problems. Although chemotherapy for toxoplasmosis is readily available, most have side effects.

Objectives

This study assesses the Dracocephalum polychaetum essential oil against T. gondii activity. In vitro, the anti-Toxoplasma effects of D. polychaetum essential oils with different concentrations were evaluated.

Methods

In the present study, T. gondii RH strain tachyzoites were exposed to D. polychaetum essential oil, and their viability effect on the parasite was evaluated. The viability test of tachyzoites was performed by using the staining method trypan blue in vitro. The inhibitory effect of D. polychaetum extract on T. gondii RH strain tachyzoites in the Vero cell line was evaluated.

Results

D. polychaetum has valuable efficacy in vitro, outperforming pyrimethamine and sulfadiazine at 30 and 90 minutes after exposure (p < 0.05). D. polychaetum essential oil showed anti-Toxoplasma activity in the cell line (IC50: 241.7 μg/mL). After T. gondii-infected Vero cells had been incubated with different concentrations of the D. polychaetum essential oil, their viability decreased in a dose-dependent manner.

Conclusions

In conclusion, D. polychaetum extract as an herbal medicine might be a valuable alternative to routine chemotherapy for toxoplasmosis.

Formulation of Neem oil-loaded solid lipid nanoparticles and evaluation of its anti-Toxoplasma activity

BACKGROUND

Toxoplasmosis is caused by an intracellular zoonotic protozoan, Toxoplasma gondii, which could be lethal in immunocompromised patients. This study aimed to synthesize Neem oil-loaded solid lipid nanoparticles (NeO-SLNs) and to evaluate the anti-Toxoplasma activity of this component.

METHODS

The NeO-SLNs were constructed using double emulsification method, and their shape and size distribution were evaluated using transmission electron microscope (TEM) and dynamic light scattering (DLS), respectively. An MTT assay was employed to evaluate the cell toxicity of the component. The anti-Toxoplasma activity of NeO-SLNs was investigated using vital (trypan-blue) staining. Anti-intracellular Toxoplasma activity of NeO-SLNs was evaluated in T. gondii-infected Vero cells.

RESULTS

The TEM analysis represented round shape NeO-SLNs with clear and stable margins. DLS analysis showed a mean particle size 337.6 nm for SLNs, and most of nanoparticles were in range 30 to 120 nm. The cell toxicity of NeO-SLNs was directly correlated with the concentration of the component (P-value = 0.0013). The concentration of NeO-SLNs, which was toxic for at least 50% of alive T. gondii (cytotoxic concentration (CC50)), was > 10 mg/mL. The ability of NeO-SLNs to kill Toxoplasma was concentration-dependent (P-value < 0.0001), and all concentrations killed at least 70% of alive tachyzoites. Furthermore, the viability of T. gondii- infected Vero cells was inversely correlated with NeO-SLNs concentrations (P-value = 0.0317), and in the concentration 100 μg/mL at least 75% of T. gondii- infected Vero cells remained alive.

CONCLUSIONS

Overall, our findings demonstrated that the NeO-SLNs was able to kill T. gondii tachyzoites in concentration 100 μg/mL with a cell toxicity lower than 20%. Such results suggest that employing SLNs as carrier for NeO can effectively kill T. gondii tachyzoites with acceptable cell toxicity. Our findings also showed that SLNs capsulation of the NeO can lead to prolonged release of the extract, suggesting that NeO-SLNs could be also employed to clear cyst stages, which should be further investigated in animal models.

Anti-Toxoplasma gondii Effects of a Novel Spider Peptide XYP1 In Vitro and In Vivo

Toxoplasmosis, caused by an obligate intracellular parasite Toxoplasma gondii, is one of the most prevalent zoonoses worldwide. Treatments for this disease by traditional drugs have shown numerous side effects, thus effective alternative anti-Toxoplasma strategies or drugs are urgently needed. In this study, a novel spider peptide, XYP1, was identified from the cDNA library of the venom gland of the spider Lycosa coelestis. Our results showed that XYP1 has potent anti-Toxoplasma activity in vitro and in vivo. Specifically, treatment with XYP1 significantly inhibited the viability, invasion and proliferation of tachyzoites with low cytotoxicity (IC₅₀ = 38.79 μΜ) on human host cells, and increased the survival rate of mice acutely infected with T. gondii. Next, scanning electron microscopy, transmission electron microscopy and RNA sequencing were employed to further explore the functional mechanism of XYP1, and the results indicated that XYP1 causes membrane perforation, swelling and disruption of tachyzoites, which could be closely associated with differential expression of several membrane-associated proteins including HSP29. In conclusion, XYP1 may be a promising new drug candidate for the treatment of toxoplasmosis.

Activity of Fluorinated Curcuminoids against Leishmania major and Toxoplasma gondii Parasites

A new 3,4-difluorobenzylidene analog of curcumin, CDF, was recently reported, which demonstrated significantly enhanced bioavailability and in vivo anticancer activity compared with curcumin. For highlighting the antiparasitic behavior of CDF, we tested this compound together with its new O-methylated analog MeCDF against Leishmania major and Toxoplasma gondii parasites. Both CDF and MeCDF were tested in vitro against L. major and T. gondii. In addition, the in vitro cytotoxicity against Vero cells and macrophages was determined and selectivity indices were calculated. The DPPH radical scavenging activity assay was carried out in order to determine the antioxidant activity of the test compounds. Both compounds showed high activities against both parasite forms with EC₅₀ values in the (sub-)micromolar range (0.35 to 0.8 μM for CDF, 0.31 to 1.2 μM for MeCDF). The higher activity of CDF against L. major amastigotes when compared with MeCDF can in parts be attributed to the antioxidant activity of CDF while MeCDF lacking any antioxidant activity was more active than CDF against T. gondii parasites. In conclusion, CDF and MeCDF are promising antiparasitic drug candidates due to their high activities against L. major and T. gondii parasites.

Phytochemicals and Potential Therapeutic Targets on Toxoplasma gondii Parasite

Identification of drug target in protozoan T. gondii is an important step in the development of chemotherapeutic agents. Likewise, exploring phytochemical compounds effective against the parasite can lead to the development of new drug agent that can be useful for prophylaxis and treatment of toxoplasmosis. In this review, we searched for the relevant literature on the herbs that were tested against T. gondii either in vitro or in vivo, as well as different phytochemicals and their potential activities on T. gondii. Potential activities of major phytochemicals, such as alkaloid, flavonoid, terpenoids and tannins on various target sites on T. gondii as well as other related parasites was discussed. It is believed that the phytochemicals from natural sources are potential drug candidates for the treatment of toxoplasmosis with little or no toxicity to humans.

In vitro and in vivo Anti-Toxoplasma activity of Dracocephalum kotschyi essential oil

Toxoplasma gondii is a zoonotic parasite of worldwide importance, responsible for toxoplasmosis in homeotherms. Although treatment options are readily available, most drugs often cause serious side effects. Extracts of Dracocephalum kotschyi (D. kotschyi) have shown significant pharmacological activity against various parasites, viruses, and bacteria. In this study, we evaluated the anti-T. gondii activity in vitro and in vivo of D. kotschyi essential oil. The thiazolyl blue tetrazolium bromide (MTT) method was used to assess the anti-T. gondii activity and cytotoxicity of the essential oil. The presence of T. gondii was observed by Giemsa staining, and the viability was evaluated by the trypan blue staining method. Furthermore, the survival rate of acutely infected mice was evaluated by intraperitoneal injecting of the essential oil (50, 100, and 200 mg kg-1 day-1) for five days after infection with 2 × 104 tachyzoites. Essential oil, negative, and positive controls that showed the best toxoplasmacidal activity were assayed in triplicate at each concentration. The essential oil exhibited the highest anti-Toxoplasma activity with a half-maximal inhibitory concentration (IC50) of 9.94 ± 0.38 µg, with a selectivity index of 2.463. On Vero cells, the CC50 of the oil was 24.49 ± 0.96 µg and exhibited a significant anti-Toxoplasma activity. Moreover, the treatment by essential oil significantly increased the survival rate compared to untreated infected control. In conclusion, the essential oil might be a useful compound, and with more testing, it may be an excellent alternative to standard chemical drugs in the treatment of toxoplasmosis.

New Pyrano-4H-benzo[g]chromene-5,10-diones with Antiparasitic and Antioxidant Activities

New pyranonaphthoquinone derivatives were synthesized and investigated for their activity against Trypanosoma brucei, Leishmania major, and Toxoplasma gondii parasites. The pentafluorophenyl derivative was efficacious against T. brucei with single digit micromolar EC₅₀ values and against T. gondii with even sub-micromolar values. The 3-chloro-4,5-dimethoxyphenyl derivative showed an activity against amastigotes of Leishmania major parasites comparable to that of amphotericin B. In addition, antioxidant activities were observed for the bromophenyl derivatives, and their redox behavior was studied by cyclovoltammetry. Anti-parasitic and antioxidative activities of the new naphthoquinone derivatives appear uncorrelated.

Urolithin-A attenuates neurotoxoplasmosis and alters innate response towards predator odor

Neurotoxoplasmosis, also known as cerebral toxoplasmosis, is an opportunistic chronic infection caused by the persistence of parasite Toxoplasma gondii cysts in the brain. In wild animals, chronic infection is associated with behavioral manipulation evident by an altered risk perception towards predators. In humans, reactivation of cysts and conversion of quiescent parasites into highly invasive tachyzoites is a significant cause of mortality in immunocompromised patients. However, the current standard therapy for toxoplasmosis is not well tolerated and is ineffective against the parasite cysts. In recent years, the concept of dietary supplementation with natural products derived from plants has gained popularity as a natural remedy for brain disorders. Notably, urolithin-A, a metabolite produced in the gut following consumption of ellagitannins-enriched food such as pomegranate, is reported to be blood-brain barrier permeable and exhibits neuroprotective effects in-vivo. In this study, we investigated the potential of pomegranate extract and urolithin-A as anti-neurotoxoplasmosis agents in-vitro and in-vivo. Treatment with pomegranate extract and urolithin-A reduced the parasite tachyzoite load and interfered with cyst development in differentiated human neural culture. Administration of urolithin-A also resulted in the formation of smaller brain cysts in chronically infected mice. Interestingly, this phenomenon was mirrored by an enhanced risk perception of the UA-treated infected mice towards predatory cues. Together, our findings demonstrate the potential of dietary supplementation with urolithin-A-enriched food as a novel natural remedy for the treatment of acute and chronic neurotoxoplasmosis.

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Pomegranate extract reduces T. gondii tachyzoite load and cyst formation in-vitro.

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Urolithin-A, in part, underlies the anti-T. gondii effect of pomegranate extract.

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Urolithin-A perturbs cyst development in the brain of chronically infected mice.

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The reduction in brain cyst burden associates with enhanced fear of infected mice towards cat odor.

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Dietary supplementation with urolithin-A is a potential therapy for neurotoxoplasmosis.

Copaifera spp. oleoresins impair Toxoplasma gondii infection in both human trophoblastic cells and human placental explants

The combination of pyrimethamine and sulfadiazine is the standard care in cases of congenital toxoplasmosis. However, therapy with these drugs is associated with severe and sometimes life-threatening side effects. The investigation of phytotherapeutic alternatives to treat parasitic diseases without acute toxicity is essential for the advancement of current therapeutic practices. The present study investigates the antiparasitic effects of oleoresins from different species of Copaifera genus against T. gondii. Oleoresins from C. reticulata, C. duckei, C. paupera, and C. pubiflora were used to treat human trophoblastic cells (BeWo cells) and human villous explants infected with T. gondii. Our results demonstrated that oleoresins were able to reduce T. gondii intracellular proliferation, adhesion, and invasion. We observed an irreversible concentration-dependent antiparasitic action in infected BeWo cells, as well as parasite cell cycle arrest in the S/M phase. The oleoresins altered the host cell environment by modulation of ROS, IL-6, and MIF production in BeWo cells. Also, Copaifera oleoresins reduced parasite replication and TNF-α release in villous explants. Anti-T. gondii effects triggered by the oleoresins are associated with immunomodulation of the host cells, as well as, direct action on parasites.

Age-related changes in cerebral congenital toxoplasmosis: Histopathological and immunohistochemical evaluation

Congenital toxoplasmosis is a widespread worldwide disease producing varying degrees of damage to the fetus including ocular and neurological impairment. However, the underlying mechanisms are not yet clear. Therefore, the current study aimed to investigate the progress of congenital cerebral toxoplasmosis in experimentally infected offspring animal model at different age groups till become adults. To fulfill this aim, the offspring of Me49 T. gondii infected pregnant mice were divided into groups; embryo, infant, young and adult phases. Blood and brain samples were collected for further hormonal and histopathological studies and immunohistochemical staining of glial fibrillary acidic protein (GFAP) and synaptophysin (SYN). Our results showed several encephalitic changes in the infected groups ranging from gliosis to reduced cortical cell number and fibrinoid degeneration of the brain. We showed increased expression of GFAP and SYN indicating activation of astrocytes and modification of the synaptic function, respectively. These changes started intrauterine following congenital infection and increased progressively afterward. Moreover, infected mice had elevated corticosterone levels. In conclusion, the current study provided new evidences for the cellular changes especially in the infected embryo and highlighted the role of GFAP and SYN that may be used as indicators for T. gondii-related neuropathy.

Anti-Toxoplasma activity and chemical compositions of aquatic extract of Mentha pulegium L. and Rubus idaeus L.: An in vitro study

This study aimed to determine the chemical compositions of crude aquatic extracts of M. pulegium L. and R. idaeus L., and their anti-Toxoplasma activity. Crude aquatic extraction of aerial parts of R. idaeus L. and M. pulegium L. was performed. GC-MS and HTPLC analyses were carried out. MTT assay was performed on Vero cells treated by different concentrations (Log -10 from 10-1 to 10-6) of the extracts. The anti-Toxoplasma activity of the concentrations was investigated using vital staining. Menthol (99.23%) and limonene (0.227%) were the major compounds of the aquatic extract of M. pulegium L. Phytochemical compositions of R. idaeus L. were terpenoids, esterols, and flavonoids. The cell toxicity of M. pulegium L. was lower than R. idaeus L. (CC50 > 10-2 versus. ≥ 10-4). Aquatic extract of M. pulegium L. showed higher anti-Toxoplasma activity (LC50 ≥ 10-6) than R. idaeus L. (LC50 ≥ 10-5). Statistically significant cell toxicity and anti-Toxoplasma activity (p < .05) were seen regarding the different concentrations of R. idaeus L. and M. pulegium L. Both R. idaeus L. and M. pulegium L. revealed anti-Toxoplasma activities. Cell toxicity of R. idaeus L. was significantly higher than M. pulegium L. M. pulegium L. extract could be more applicable due to its lower cell toxicity.

Promising In Vitro Anti-Toxoplasma gondii Effects of Commercial Chitosan

CDATA[Background: Toxoplasmosis is a disease that results from infection with an obligate intracellular T. gondii parasite, one of the world's most common parasites. Considering the complications of chemical drugs and the need for an appropriate drug combination for treatment of toxoplasmosis and considering the antimicrobial potential of chitosan, as a natural source, this study was aimed to evaluate in vitro activity of commercial chitosan (CC) on T. gondii.

METHODS

In this experimental study, the tachyzoites of T. gondii were collected from the peritoneal exudates from infected Balb/c mice. The tachyzoites were diluted in phosphate buffer saline (PBS) solution. Chitosan with low molecular weight was commercially purchased. Then, at concentrations of 10, 50, 100, and 200 μg/mL and after 30, 60, 120, and 180 minutes, the viability of tachyzoites was determined by using trypan blue 0.1%. Anti-T.gondii activity of CC in all concentrations was significantly higher than pyrimethamine as the control group (P=0.05).

RESULTS

The concentration of 200 μg/mL of CC had the highest effects and killed 30.5, 52, 59, and 81.5% of tachyzoites after 30, 60, 120, and 180 minutes. Moreover, IC50 values of CC were 515, 171, 12.5, and <10 μg/mL in comparison with pyrimethamine as 58.82 μg/mL for 30, 60, 120, and 180 min of exposure time.

CONCLUSION

Our results indicate that chitosan in low molecular weight had potent activity against T. gondii tachyzoites and could be an appropriate candidate for the treatment of at least acute toxoplasmosis, certainly, after complementary in vivo experiments.

Anti-toxoplasma, antioxidant and cytotoxic activities of Pleopeltis crassinervata (Fée) T. Moore hexane fraction

The apicomplexan parasite Toxoplasma gondii (T. gondii) causes toxoplasmosis in humans. Pyrimethamine and sulfadiazine that are the drugs of choice to treat the disease, produce severe side effects as well as failure treatments because of drug resistance; thus, novel anti-Toxoplasma compounds are needed and natural compounds can be a good source to obtain them, as medicinal plants have been used to control other apicomplexan parasites. Pleopeltis crassinervata (P. crassinervata) is a fern used in some rural areas of Mexico to treat among other malaises, mouth ulcers, gastrointestinal problems and parasites. Therefore, the efficacy of extracts and fractions obtained from P. crassinervata fronds was evaluated on the viability of T. gondii RH strain tachyzoites by the Stytox green method. RH is the prototypical type 1 Toxoplasma strain, isolated for the first time from the brain of a patient boy named R. H. Its phytochemical profile, MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, Hep-2 cytotoxicity and antioxidant activity by ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) methods, were also assessed. Hexane fraction exhibited the highest anti-Toxoplasma activity with an IC50 of 16.90 µg/mL. This fraction did not show antioxidant activity and contained at least 2 terpenoid type compounds with retention factor (Rf) of 0.75 and 0.86. The fraction was not toxic to the host cells in doses up to 50 µg/mL. P. crassinervata frond hexane fraction seems to be a good candidate to obtain possible anti-Toxoplasma compounds. This study is the first to report the biological, antioxidant and cytotoxic activity of P. crassinervata fern.

Nanomedicine advances in toxoplasmosis: diagnostic, treatment, and vaccine applications

Toxoplasmosis is an infectious disease caused by the intracellular parasite Toxoplasma gondii that affects about one third of the world's population. The diagnosis of this disease is carried out by parasite isolation and host antibodies detection. However, the diagnosis presents problems in regard to test sensitivity and specificity. Currently, the most effective T. gondii treatment is a combination of pyrimethamine and sulfadiazine, although both drugs are toxic to the host. In addition to the problems that compromise the effective diagnosis and treatment of toxoplasmosis, there are no reports or indications of any vaccine capable of fully protecting against this infection. Nanomaterials, smaller than 1000 nm, are currently being investigated as an alternative tool in the management of T. gondii infection. This article reviews how recent nanotechnology advances indicate the utility of nanomaterials in toxoplasmosis diagnosis, treatment, and vaccine development.