Prophylactic Activity of Biogenic Selenium Nanoparticles Against Chronic Toxoplasma gondii Infection.

BACKGROUND: Studies showed that biogenic selenium nanoparticles (SeNPs) have a number of pharmacological properties, such as antimicrobial ones. OBJECTIVE: The present investigation assesses the efficacy of biogenic selenium nanoparticles (SeNPs) as a new patent against latent toxoplasmosis in a mice model. METHODS: Male BALB/c mice were orally treated with SeNPs at the doses of 2.5, 5, 10 mg/kg once a day for 14 days. On the 15th day, the mice were infected with the intraperitoneal inoculation of 20-25 tissue cysts from the Tehran strain of Toxoplasma gondii. The mean numbers of brain tissue cysts and the mRNA levels of TNF-α, IL-12, IL-10, IFN-γ, and inducible nitric oxide synthase (iNOS) in mice of each tested group were measured. Moreover, serum clinical chemistry factors in treated mice were examined to determine the safety of SeNPs. RESULTS: The mean number of the brain tissue cysts was significantly (P<0.001) decreased in mice treated with SeNPs at doses 2.5 (n=37), 5 (n=11), and 10 mg/kg (n=3) based on a dose dependent manner compared with the control group (n=587). The mRNA levels of IFN-γ, TNF-α, IL-12, and iNO were significantly increased in mice treated with SeNPs at the doses 10 mg/kg compared with control subgroups (p<0.05). No significant variation (p>0.05) was observed in the clinical chemistry parameters among the mice in the control subgroups compared with groups treated with SeNPs. CONCLUSION: The results of the present study showed a new patent in the treatment of toxoplasmosis; so that taking the biogenic selenium nanoparticles in concentrations of 2.5-10 mg/kg for 2 weeks was able to prevent severe symptoms of the toxoplasmosis in a mice model. This indicated the prophylactic effects of SeNPs with no considerable toxicity against latent toxoplasmosis. However, more studies are required to elucidate the correct anti-Toxoplasma mechanisms of SeNPs.

Efficacy and Safety Curcuma zadoaria L. to Inactivate the Hydatid Cyst Protoscoleces.

BACKGROUND: The present work aimed to evaluate the chemical composition of Curcuma zadoaria essential oil and to investigate its efficacy and safety against hydatid cyst protoscoleces. METHODS: Collected protoscoleces from liver fertile hydatid cysts of infected sheep were exposed to different concentrations of the essential oil (75, 150, 300 µl/mL) for 5-30 min in vitro and ex vivo. Then, by using the eosin exclusion assay, the viability of protoscoleces was studied. In the next step, 24 male NMRI mice were examined to assess the toxicity of C. zadoaria essential oil by measuring the biochemical and hematological parameters. RESULTS: Based on the obtained results, the LD50 value of intraperitoneal injection of the C. zadoaria essential oil was 1.76 mL/kg of body weight and the maximum non-fatal dose was 0.96 mL/kg of body weight. C. zadoaria essential oil had a strong proto scolicidal activity in vitro so that at the 300 and 150 µl/ml entirely eliminates the parasite after 5 and 10 minutes; whereas, weak proto scolicidal activity was observed at lower doses. Ex vivo assay, no similar effect with in vitro was observed, therefore, more time is required to show a potent proto scolicidal activity. C. zadoaria essential oil at the concentrations of 300 and 150 µl/mL after an exposure time of 7 and 12 min, killed 100% of protoscoleces within the hydatid cyst, respectively. After intraperitoneal injection of the C. zadoaria essential oil for 2 weeks, no significant difference (p > 0.05) was observed in the clinical chemistry and hematologic parameters at the doses of 0.15, 0.3, 0.6 mL/kg. CONCLUSION: The obtained results in vitro and ex vivo exhibited that C. zadoaria essential oil had a favorable proto scolicidal activity on hydatid cyst protoscoleces. However, more supplementary works are required to verify these findings by assessing clinical subjects.

Leishmanicidal and cytotoxic activities of Nigella sativa and its active principle, thymoquinone.

CONTEXT: Leishmaniasis is a complex disease with a broad spectrum of clinical presentations. OBJECTIVE: We evaluated the anti-leishmanial effects of Nigella sativa L. (Ranunculaceae) against Leishmania tropica and Leishmania infantum with an in vitro model. MATERIALS AND METHODS: Antileishmanial effects of essential oil and methanolic extract of N. sativa (0-200 µg/mL) and thymoquinone (0-25 µg/mL) on promastigotes of both species and their cytotoxicity activities against murine macrophages were evaluated using the MTT assay at 24, 48, and 72 h. Moreover, their leishmanicidal effects against amastigotes were investigated in a macrophage model, for 48 and 72 h. RESULTS: The findings showed that essential oil (L. tropica IC50 9.3 µg/mL and L. infantum IC50 11.7 µg/mL) and methanolic extract (L. tropica IC50 14.8 µg/mL and L. infantum IC50 15.7 µg/mL) of N. sativa, particularly thymoquinone (L. tropica IC50 1.16 µg/mL and L. infantum IC50 1.47 µg/mL), had potent antileishmanial activity on promastigotes of both species after 72 h. In addition, essential oil (L. tropica IC50 21.4 µg/mL and L. infantum IC50 26.3 µg/mL), methanolic extract (L. tropica IC50 30.8 µg/mL and L. infantum IC50 34.6 µg/mL), and thymoquinone (L. tropica IC50 2.1 µg/mL and L. infantum IC50 2.6 µg/mL) mediated a significant decrease in the growth rate of amastigote forms of both species. Thymoquinone (CC50 38.8 µg/mL) exhibited higher cytotoxic effects against murine macrophages than the other extracts. CONCLUSION: N. sativa, especially its active principle, thymoquinone, showed a potent leishmanicidal activity against L. tropica and L.infantum with an in vitro model.

Evaluation of antileishmanial activity and cytotoxicity of the extracts of Berberis vulgaris and Nigella sativa against Leishmania tropica.

BACKGROUND & OBJECTIVES: Leishmaniasis is a major public health problem, and the alarming spread of parasite resistance underlines the importance of discovering new therapeutic products. The present study aims to investigate the in vitro antileishmanial activity and cytotoxicity of the ethanolic extract of Berberis vulgaris fruits and chloroform extract of Nigella sativa seeds against Leishmania tropica. METHODS: In this study, antileishmanial activity of B. vulgaris and N. sativa extracts on promastigote and amastigote stages of L. tropica in comparison to meglumine antimoniate (MA) was evaluated, using MTT assay and macrophage model, respectively. MTT test was also used to assess the cytotoxicity of extracts on murine macrophages. The significance of differences was determined by analysis of variances (ANOVA) and student's t-test using SPSS software. RESULTS: The results showed that ethanolic extract of B. vulgaris (IC50 4.83 µg/ml) and chloroform extract of N. sativa (IC50 7.83 µg/ml) significantly reduced the viability of promastigotes of L. tropica in comparison to MA (IC50 11.26 µg/ml). Furthermore, extracts of B. vulgaris (IC50 24.03 µg/ml) and N. sativa (IC50 30.21 µg/ml) significantly decreased the growth rate of amastigotes in each macrophage as compared with positive control (p <0.05). Our findings also revealed that extracts of B. vulgaris and N. sativa had no significant cytotoxicity against murine macrophages. CONCLUSION: The B. vulgaris and N. sativa extracts exhibited an effective leishmanicidal activity against L. tropica on in vitro model. Further, works are required to evaluate the exact effect of these extracts on Leishmania species using a clinical setting.

Scolicidal effects of biogenic selenium nanoparticles against protoscolices of hydatid cysts.

Cystic echinococcosis (hydatid cyst, CE) as a zoonotic parasitic infection caused by the larval stage of the dog tapeworm Echinococcus granulosus is still an important economic and public health concern in the world. One of the treatment options for CE is surgical removal of the cysts combined with chemotherapy using albendazole and/or mebendazole before and after surgery. Currently, many scolicidal agents, which have some complications, have been used for inactivation of the cyst contents. Therefore the development of new scolicidal agents with low side effects and more efficacies is an urgent need for surgeons. The present study was aimed to investigate the in vitro scolicidal effect of selenium nanoparticles biosynthesized by a newly isolated marine bacterial strain Bacillus sp. MSh-1 against protoscoleces of E. granulosus. Protoscolices were aseptically aspirated from sheep livers having hydatid cysts. Various concentrations (50-500 µg/ml) of Se NPs (in size range of about 80-220 nm) were used for 10-60 min. Viability of protoscoleces was confirmed by 0.1% eosin staining. The results indicated that biogenic Se NPs at all concentrations have potent scolicidal effects especially at concentrations 500 and 250 µg/ml after 10 and 20 min of application, respectively. In conclusion, the findings of present study proven that Se NPs have potent scolicidal effects, therefore may be used in CE surgery. However, the in vivo efficacy of these NPs remains to be explored.