MicroRNA mmu-miR-511-5p: A promising Diagnostic Biomarker in Experimental Toxoplasmosis Using Different Strains and Infective Doses in Mice with Different Immune States Before and After Treatment.

PURPOSE: Searching for a novel early diagnostic biomarker for toxoplasmosis, real-time-PCR was currently used to measure the serum mmu-miR-511-5p level in male Swiss-albino mice infected with either; ME49 or RH Toxoplasma gondii (T. gondii) strains. METHODS: Three mice groups were used; (GI) constituted the non-infected control group, while (GII) and (GIII) were experimentally infected with ME49 or RH strains, respectively. GII mice were orally infected using 10 or 20 ME49 cysts (ME-10 and ME-20), both were subdivided into; non-treated (ME-10-NT and ME-20-NT) and were further subdivided into; immunocompetent (ME-10-IC and ME-20-IC) [euthanized 3-days, 1, 2, 6 or 8-weeks post-infection (PI)], and immunosuppressed using two Endoxan® injections (ME-10-IS and ME-20-IS) [euthanized 6- or 8-weeks PI], and spiramycin-treated (ME-10-SP and ME-20-SP) that received daily spiramycin, for one-week before euthanasia. GIII mice individually received 2500 intraperitoneal RH strain tachyzoites, then, were subdivided into; non-treated (RH-NT) [euthanized 3 or 5-days PI], and spiramycin-treated (RH-SP) that were euthanized 5 or 10-days PI (refer to the graphical abstract). RESULTS: Revealed significant upregulation of mmu-miR-511-5p in GII, one-week PI, with gradually increased expression, reaching its maximum 8-weeks PI, especially in ME-20-NT group that received the higher infective dose. Immunosuppression increased the upregulation. Contrarily, treatment caused significant downregulation. GIII recorded significant upregulation 3-days PI, yet, treatment significantly decreased this expression. CONCLUSION: Serum mmu-miR-511-5p is a sensitive biomarker for early diagnosis of ME49 and RH infection (as early as one-week and 3-days, respectively), and its expression varies according to T. gondii infective dose, duration of infection, spiramycin-treatment and host immune status.

Intestinal schistosomiasis: Can a urine sample decide the infection?

Intestinal schistosomiasis, one of the neglected tropical diseases whose control depends on accurate diagnosis of the disease prevalence. The use of low sensitive Kato Katz (KK) fecal egg detection method as a reference gold standard is not an accurate indication especially in low transmission areas. Latent class analysis frameworks especially the Bayesian could be used instead to compare between different diagnostic tests without the use of a gold standard method as a reference. Thus, this study compared two urine-based tests for the detection of circulating antigen and cell free DNA of Schistosoma mansoni versus KK method using the Bayesian latent class analytical framework and in two models where the trace results of point of contact - assay of circulating cathodic antigen (POC-CCA) were once estimated as positive, and as negative in the other model. The Bayesian framework in the trace CCA positive model showed an estimate of disease prevalence of 26% (95% BCI:0 to 60%). POC-CCA showed the highest sensitivity (74% with BCI: 9 to 91%) and lowest specificity for (20% with BCI: 0% to 37%) and the reverse for KK. For POC-CCA with traces considered negative, it was found that results between the three tests were moderated where the positivity for infection by Schistosoma antigen detection and PCR for cell free DNA approached that estimated by the Bayesian framework (44%), and the specificity for point of contact assay(81%; 95%BCI: 59% to 100%) rose in hand with its sensitivity(77%, 95% BCI:53% to 100%) and with results for PCR test (sensitivity = 80%; 95% BCI: 61% to 100%, specificity = 69%; 95% BIC: 47% to 100%). KK remains with the highest specificity while its sensitivity in the two models never exceeded 22%. Thus, we conclude that the use of a single urine sample could be very sensitive and highly specific in the diagnosis of intestinal schistosomiasis using either the trace negative model of point of contact assay, or conventional PCR, when compared to the fecal egg detection using duplicate KK. However, the use of a single tool restricts the management of the disease in areas of low endemicity.

In vitro effectivity of three approved drugs and their synergistic interaction against Leishmania infantum. / Efectividad in vitro de tres fármacos aprobados y su interacción sinérgica contra Leishmania infantum

INTRODUCTION: Leishmaniasis remains one of the neglected tropical diseases. Repurposing existing drugs has proven to be successful for treating neglected tropical diseases while combination therapy is a strategic alternative for the treatment of infectious diseases. Auranofin, lopinavir/ritonavir, and sorafenib are FDA approved drugs used in the treatment of diverse diseases by acting on different essential biological enzymes. OBJECTIVE: To evaluate the effects of monotherapy and combined therapies with the three drugs against Leishmania infantum. MATERIALS AND METHODS: We compared the leishmanicidal effects of the three drugs on promastigotes in vitro as regards the parasite count, the drug concentration providing a half-maximal response, and the ultrastructural changes of the parasite. We determined the fractional inhibitory concentration index of combined drugs in two ways, as well as the activity of the three drugs together to establish their synergetic effect. RESULTS: The monotherapy with the three drugs was effective with auranofin showing the best leishmanicidal effect (EC50=1.5 µM), whereas sorafinib reduced parasite growth at EC50=2.5 µM. The scanning electron microscopy of promastigotes from all treated media showed distortion in the shape with loss of flagella and bleb formation. Acidocalcinosis was evident by transmission electron microscopy with all treatments suggesting apoptosis. Treatment with lopinavir/ritonavir showed signs of autophagy. The two-way combination of the drugs led to additive interactions while the combination of the three drugs showed synergistic action. CONCLUSION: Each drug when used as monotherapy against Leishmania spp. was effective, but the combination therapy was more effective than the individual drugs due to the additive or synergistic effects.

Introducción. La leishmaniasis sigue siendo una de las enfermedades tropicales desatendidas. La reutilización de medicamentos existentes ha demostrado ser exitosa para tratar enfermedades tropicales desatendidas y la terapia combinada es una alternativa estratégica para el tratamiento de enfermedades infecciosas. Auranofin, lopinavir/ritonavir y sorafenib son medicamentos aprobados por la Food and Drug Administration (FDA) de Estados Unidos utilizados en el tratamiento de diversas enfermedades, pues actúan sobre diferentes enzimas biológicas esenciales. Objetivo. Evaluar los efectos terapéuticos de la monoterapia y de los tres fármacos combinados contra Leishmania infantum. Materiales y métodos. Los efectos leishmanicidas de los tres fármacos sobre los promastigotes se compararon in vitro en cuanto al recuento de parásitos, la concentración del fármaco que proporcionara una respuesta semimáxima y los cambios ultraestructurales del parásito. Se calculó el índice de concentración inhibitoria de fracciones de fármacos combinados de dos maneras y la actividad de los tres fármacos juntos para determinar el efecto sinérgico. Resultados. La monoterapia con los tres medicamentos fue efectiva, pero la auranofina tuvo el mejor efecto antileishmanicida con un CE50 de 1,5 µM, en tanto que el sorafinib redujo el crecimiento del parásito con un CE50 de 2,5 µM. La microscopía electrónica de barrido de promastigotes de todos los medios tratados mostró una distorsión en la forma, con pérdida de flagelos y formación de ampollas. La acidocalcinosis fue evidente por microscopía electrónica de transmisión con todos los tratamientos, lo que sugiere apoptosis. El tratamiento con lopinavir/ritonavir mostró signos de autofagia. La combinación de dos medicamentos condujo a interacciones aditivas, mientras que la combinación de las tres drogas produjo una acción sinérgica. Conclusión. Los tres medicamentos usados como monoterapia contra Leishmania spp. fueron efectivos, pero el tratamiento combinado lo fue en mayor medida debido a los efectos aditivos o sinérgicos.

In vitro effectivity of three approved drugs and their synergistic interaction against Leishmania infantum / Efectividad in vitro de tres fármacos aprobados y su interacción sinérgica contra Leishmania infantum

Introduction: Leishmaniasis remains one of the neglected tropical diseases. Repurposing existing drugs has proven to be successful for treating neglected tropical diseases while combination therapy is a strategic alternative for the treatment of infectious diseases. Auranofin, lopinavir/ritonavir, and sorafenib are FDA approved drugs used in the treatment of diverse diseases by acting on different essential biological enzymes. Objective: To evaluate the effects of monotherapy and combined therapies with the three drugs against Leishmania infantum. Materials and methods: We compared the leishmanicidal effects of the three drugs on promastigotes in vitro as regards the parasite count, the drug concentration providing a half-maximal response, and the ultrastructural changes of the parasite. We determined the fractional inhibitory concentration index of combined drugs in two ways, as well as the activity of the three drugs together to establish their synergetic effect. Results: The monotherapy with the three drugs was effective with auranofin showing the best leishmanicidal effect (EC50=1.5 µM), whereas sorafinib reduced parasite growth at EC50=2.5 µM. The scanning electron microscopy of promastigotes from all treated media showed distortion in the shape with loss of flagella and bleb formation. Acidocalcinosis was evident by transmission electron microscopy with all treatments suggesting apoptosis. Treatment with lopinavir/ritonavir showed signs of autophagy. The two-way combination of the drugs led to additive interactions while the combination of the three drugs showed synergistic action. Conclusion: Each drug when used as monotherapy against Leishmania spp. was effective, but the combination therapy was more effective than the individual drugs due to the additive or synergistic effects.

Introducción. La leishmaniasis sigue siendo una de las enfermedades tropicales desatendidas. La reutilización de medicamentos existentes ha demostrado ser exitosa para tratar enfermedades tropicales desatendidas y la terapia combinada es una alternativa estratégica para el tratamiento de enfermedades infecciosas. Auranofin, lopinavir/ritonavir y sorafenib son medicamentos aprobados por la Food and Drug Administration (FDA) de Estados Unidos utilizados en el tratamiento de diversas enfermedades, pues actúan sobre diferentes enzimas biológicas esenciales. Objetivo. Evaluar los efectos terapéuticos de la monoterapia y de los tres fármacos combinados contra Leishmania infantum. Materiales y métodos. Los efectos leishmanicidas de los tres fármacos sobre los promastigotes se compararon in vitro en cuanto al recuento de parásitos, la concentración del fármaco que proporcionara una respuesta semimáxima y los cambios ultraestructurales del parásito. Se calculó el índice de concentración inhibitoria de fracciones de fármacos combinados de dos maneras y la actividad de los tres fármacos juntos para determinar el efecto sinérgico. Resultados. La monoterapia con los tres medicamentos fue efectiva, pero la auranofina tuvo el mejor efecto antileishmanicida con un CE50 de 1,5 µM, en tanto que el sorafinib redujo el crecimiento del parásito con un CE50 de 2,5 µM. La microscopía electronica de barrido de promastigotes de todos los medios tratados mostró una distorsión en la forma, con pérdida de flagelos y formación de ampollas. La acidocalcinosis fue evidente por microscopía electrónica de transmisión con todos los tratamientos, lo que sugiere apoptosis. El tratamiento con lopinavir/ritonavir mostró signos de autofagia. La combinación de dos medicamentos condujo a interacciones aditivas, mientras que la combinación de las tres drogas produjo una acción sinérgica. Conclusión. Los tres medicamentos usados como monoterapia contra Leishmania spp. fueron efectivos, pero el tratamiento combinado lo fue en mayor medida debido a los efectos aditivos o sinérgicos.

Cannabinoid receptor-1 antagonism: a new perspective on treating a murine schistosomal liver fibrosis model.

BACKGROUND: Formation of schistosomal granulomata surrounding the ova can result in schistosomiasis-associated liver fibrosis (SSLF). The current standard of treatment is praziquantel (PZQ), which cannot effectively reverse SSLF. The role of the cannabinoid (CB) receptor family in liver fibrosis has recently been highlighted. OBJECTIVES: This study aimed to assess the therapeutic effect of CB1 receptor antagonism in reversing SSLF in a murine model of Schistosoma mansoni infection. METHODS: One hundred male Swiss albino mice were divided equally into five groups: healthy uninfected control (group I), infected control (group II), PZQ treated (group III), rimonabant (RIM) (SR141716, a CB1 receptor antagonist)-treated (group IV) and group V was treated with combined PZQ and RIM. Liver sections were obtained for histopathological examination, alpha-1 smooth muscle actin (α-SMA) immunostaining and assessment of CB1 receptor expression using real-time polymerase chain reaction (RT-PCR). FINDINGS: The most effective reduction in fibrotic marker levels and granuloma load was achieved by combined treatment with PZQ+RIM (group V): CB1 receptor expression (H = 26.612, p < 0.001), number of α-SMA-positive cells (F = 57.086, p < 0.001), % hepatic portal fibrosis (F = 42.849, p < 0.001) and number of granulomata (F = 69.088, p < 0.001). MAIN CONCLUSIONS: Combining PZQ with CB1 receptor antagonists yielded the best results in reversing SSLF. To our knowledge, this is the first study to test this regimen in S. mansoni infection.

Evaluation of nitazoxanide as a novel drug for the treatment of acute and chronic toxoplasmosis.

Toxoplasmosis is a widespread, neglected disease with significant morbidity and mortality. In search of an effective treatment, nitazoxanide (NTZ) was evaluated in the treatment of acute and chronic toxoplasmosis in experimental mice. For this purpose, mice were infected with 20 cysts (acute infection model) or 10 cysts (chronic infection model) of Toxoplasma gondii (ME 49 strain). Treated mice received NTZ (at doses of 100 and 150 mg/kg), starting from the third day (acute model) or the fifth week (chronic model) post-infection, which continued for 14 consecutive days. The effects of NTZ were evaluated in comparison to the pyrimethamine/sulfadiazine combination. Evaluation included mortality rates, brain cyst count, inflammatory scoring and immunological studies. The latter included estimation of interferon-gamma (IFN-γ) and induced nitric oxide synthase (iNOS). In the acute infection model, NTZ at 100 and 150 mg/kg significantly reduced the number of brain cysts by 78 and 87% compared to the infected untreated controls and reduced the mortality rate to 24 and 20%, respectively, compared with 44% in the infected untreated control. In the chronic infection model, cyst reduction reached 32 and 38% for 100 and 150 mg/kg NTZ treatments, respectively. NTZ was significantly able to reduce inflammation caused by acute and chronic T. gondii infection with slight necrosis and few infiltrating mononuclear cells. Additionally, the immunological analysis revealed that NTZ significantly increased the production of serum IFN-γ and enhanced iNOS production in brain tissue, suggesting an immunomodulatory role for the drug. Based on the findings of the present study, it can be concluded that NTZ is a potential drug for the treatment of acute and chronic toxoplasmosis.

Urinary circulating DNA and circulating antigen for diagnosis of schistosomiasis mansoni: a field study.

OBJECTIVE: To evaluate three non-invasive assays for the diagnosis of schistosomiasis mansoni in an Egyptian village. METHODS: Urine was collected for the detection of circulating cathodic antigen (CCA) and cell-free parasite DNA (cfpd) by Point-of-contact (POC)-cassette assay and PCR, respectively. These tests were compared to Kato-Katz (KK) faecal thick smear for detection of Schistosoma mansoni eggs. RESULTS: Disease prevalence by POC-CCA assay was 86%; by PCR it was 39% vs. 27% by KK. Compared to KK, the sensitivity of POC-CCA reached 100%, but its specificity was only 19.2% with 41% accuracy. Sensitivity of the PCR assay for cfpd was 55.56%, and specificity was 67.12% with 64% accuracy. A new end point was calculated for combined analysis of KK, POC-CCA assay and PCR. Sensitivity for the three tests was 52.94%, 90.2% and 76.47%; specificity was 100% for KK and PCR and 18.37% for POC-CCA. The accuracy calculated for the three tests at the end point was 76% for KK, 55% for POC-CCA assay and 88% for PCR. CONCLUSION: Conventional PCR assay for detection of cfpd provides a potential screening tool for intestinal schistosomiasis with reliable specificity, reasonable accuracy and affordable financial and technical cost.

OBJECTIF: Evaluer trois tests non invasifs pour le diagnostic de la schistosomiase mansoni dans un village égyptien. MÉTHODES: L'urine a été collectée pour la détection de l'antigène cathodique circulant (ACC) et de l'ADN du parasite libéré des cellules (cfpd) par le test en cassette POC (point-of-contact) et par PCR, respectivement. Ces tests ont été comparés au test de Kato Katz (KK) sur frottis fécal épais pour la détection des œufs de Schistosoma mansoni. RÉSULTATS: La prévalence de la maladie par dosage POC-ACC était de 86%; elle était de 39% par PCR contre 27% par KK. Par rapport à KK, la sensibilité du POC-ACC atteignait 100%, mais sa spécificité n'était que de 19,2% avec une précision de 41%. La sensibilité du PCR pour la cfpd était de 55,56% et sa spécificité de 67,12% avec une précision de 64%. Un nouveau seuil a été calculé pour l'analyse combinée des tests KK, POC-ACC et PCR. La sensibilité pour les trois tests était de 52,94%, 90,2% et 76,47%; la spécificité était de 100% pour KK et PCR et de 18,37% pour POC-ACC. La précision calculée pour les trois tests au point seuil était de 76% pour KK, 55% pour le POC-ACC et 88% pour la PCR. CONCLUSION: Le test PCR conventionnel pour la détection de la cfpd constitue un outil de dépistage potentiel de la schistosomiase intestinale avec une spécificité fiable, une précision raisonnable et un coût financier et technique abordable.

Cannabinoid receptor-1 antagonism: a new perspective on treating a murine schistosomal liver fibrosis model

BACKGROUND Formation of schistosomal granulomata surrounding the ova can result in schistosomiasis-associated liver fibrosis (SSLF). The current standard of treatment is praziquantel (PZQ), which cannot effectively reverse SSLF. The role of the cannabinoid (CB) receptor family in liver fibrosis has recently been highlighted. OBJECTIVES This study aimed to assess the therapeutic effect of CB1 receptor antagonism in reversing SSLF in a murine model of Schistosoma mansoni infection. METHODS One hundred male Swiss albino mice were divided equally into five groups: healthy uninfected control (group I), infected control (group II), PZQ treated (group III), rimonabant (RIM) (SR141716, a CB1 receptor antagonist)-treated (group IV) and group V was treated with combined PZQ and RIM. Liver sections were obtained for histopathological examination, alpha-1 smooth muscle actin (α-SMA) immunostaining and assessment of CB1 receptor expression using real-time polymerase chain reaction (RT-PCR). FINDINGS The most effective reduction in fibrotic marker levels and granuloma load was achieved by combined treatment with PZQ+RIM (group V): CB1 receptor expression (H = 26.612, p < 0.001), number of α-SMA-positive cells (F = 57.086, p < 0.001), % hepatic portal fibrosis (F = 42.849, p < 0.001) and number of granulomata (F = 69.088, p < 0.001). MAIN CONCLUSIONS Combining PZQ with CB1 receptor antagonists yielded the best results in reversing SSLF. To our knowledge, this is the first study to test this regimen in S. mansoni infection.

The effect of lopinavir/ritonavir and lopinavir/ritonavir loaded PLGA nanoparticles on experimental toxoplasmosis.

A marked reduction has been achieved in the incidence and clinical course of toxoplasmic encephalitis after the introduction of protease inhibitors within the treatment regimen of HIV (HIV-PIs). This work was undertaken to study for the first time, the efficacy of HIV-PIs, lopinavir/ritonavir (L/R), as a therapeutic agent in acute experimental toxoplasmosis. Lopinavir/ritonavir (L/R) were used in the same ratio present in aluvia, a known HIV-PIs drug used in the developing countries in the treatment regimens of AID's patient. Poly lactic-co-glycolic acid (PLGA) nanoparticles were used as a delivery system to L/R therapy. L/R alone or after its encapsulation on PLGA were given to Swiss strain albino mice that were infected with RH virulent toxoplasma strain. Both forms caused parasitological improvement in both mortality rate and parasite count. The higher efficacy was achieved by using L/R PLGA together with minimizing the effective dose. There was significant reduction in the parasite count in the peritoneal fluid and the liver. Parasite viability and infectivity were also significantly reduced. The anti-toxoplasma effect of the drug was attributed to the morphological distortion of the tachyzoites as evident by the ultrastructure examination and suppressed the egress of tachyzoites. L/R also induced changes that suggest apoptosis and autophagy of tachyzoites. The parasitophorous vacuole membrane was disrupted and vesiculated. The nanotubular networks inside the parasitophorous vacuole were disrupted. Therefore, the present work opens a new possible way for the approved HIV-PIs as an alternative treatment against acute toxoplasmosis. Furthermore, it increases the list of the opportunistic parasites that can be treated by this drug. The successful in vivo effect of HIV-PIs against Toxoplasma gondii suggests that this parasite may be a target in HIV treated patients, thus decrease the possibility of toxoplasmic encephalitis development.

Encephalitozoon cuniculi infection among immunocompromised and immunocompetent humans in Egypt.

BACKGROUND: Encephalitozoon cuniculi infects a wide range of homoeothermic animals, including man. Complications due to this microsporidian have been reported only in immunocompromised patients. Reports on E. cuniculi in immunocompetent humans are lacking, most probably, because it is not linked to any clinical manifestations in such hosts. The present work was carried out with the aim of studying, for the first time in Egypt, the prevalence of E. cuniculi infection of urinary tract among non-HIV immunocompromised patients and immunocompetent individuals. It tested also the influence of some factors on the risk of infection. METHODS: Blood and urine samples were collected from 88 persons (44 non-HIV immunocompromised patients and 44 subjects as immunocompetent control group). IFAT serological assay and Weber's green modified trichrome stain (MTS) urine smears were carried out. Molecular study by PCR was also performed to detect DNA of E. cuniculi in urine samples. A full history sheet was fulfilled for each subject to test the suspected risk factors. RESULTS: The IFAT examination confirmed the presence of antibodies against E. cuniculi in 44.3% of the human subjects. The seroprevalence of E. cuniculi was significantly higher in the immunocompromised patients compared with the immunocompetent individuals (77.3% versus 11.4%). Compared with IFAT (the gold standard), the sensitivity and specificity of Weber's green MTS smears were 69.23% and 89.80%. By using PCR, no positive cases were detected among human subjects. CONCLUSION: A high prevalence of E. cuniculi infection in the studied individuals was noted. Although infection was found in some immunocompetent individuals, the immune status of the host remains the corner stone for occurrence of the infection.