Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 340
Filtrar
1.
Acta Parasitol ; 69(1): 567-573, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38231312

RESUMO

PURPOSE: Pyrus boissieriana is a rich source of arbutin and has been used in herbal medicine to treat infectious diseases. This study aimed to investigate the effect of the arbutin-rich fraction of Pyrus boissieriana aerial parts on Toxoplasma gondii In Vitro and In Vivo. METHODS: An arbutin-rich fraction of P. boissieriana was prepared beforehand. Flow cytometry was used to evaluate the effect of different concentrations (1-512 µg/ml) of the P. boissieriana arbutin-rich fraction on Toxoplasma tachyzoites (RH strain). The cytotoxicity of the concentrations on the macrophage J774 cell line was also investigated by MTT assay. For In Vivo investigation, 4-6-week-old female mice infected with the RH strain of T. gondii were treated with different doses (16, 32, 64, 256, and 512 mg/kg) of the fraction using gavage. RESULTS: The highest and lowest lethality of the tachyzoites were 89.6% and 25.9% related to the concentrations of 512 µg/ml and 1 µg/ml, respectively, with an IC50 value of 18.1 µg/ml ± 0.37. The cytotoxicity test showed an IC50 value of 984.3 µg/ml ± 0.76 after 48 h incubation. The mean survival of mice at the lowest treated dose (16 mg/kg) was 6.6 days, and it was 15 days at the highest dose (512 mg/kg). The concentrations of 512, 256, 128, and 64 mg/kg of the fraction compared to the negative control (6.2 days mean survival) significantly increased the survival time of mice (P < 0.001, P = 0.009, P = 0.018, and P = 0.021, respectively). CONCLUSION: The results showed that the arbutin-rich fraction of P. boissieriana is effective against T. gondii In Vitro and In Vivo and may be a reliable alternative to conventional treatment for toxoplasmosis, although further studies are necessary.


Assuntos
Antiprotozoários , Arbutina , Extratos Vegetais , Toxoplasma , Animais , Toxoplasma/efeitos dos fármacos , Camundongos , Feminino , Extratos Vegetais/farmacologia , Linhagem Celular , Arbutina/farmacologia , Antiprotozoários/farmacologia , Macrófagos/parasitologia , Macrófagos/efeitos dos fármacos , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/parasitologia , Concentração Inibidora 50 , Toxoplasmose/tratamento farmacológico , Toxoplasmose/parasitologia
2.
Acta Parasitol ; 68(4): 880-890, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37924457

RESUMO

BACKGROUND: Toxoplasmosis is a cosmopolitan parasitic infection caused by Toxoplasma gondii which is commonly treated by pyrimethamine (PYR) plus sulfadiazine (SDZ) with several adverse side effects. The present study evaluated the therapeutic effects of Urtica dioica L. aqueous extract (UDE) on acute and chronic toxoplasmosis in mice. METHODS: For this purpose, mice were infected with 20 cysts (acute infection) or 10 cysts (chronic infection) of T. gondii (Me49 strain). The mice were treated with 200 mg/kg of UDE intraperitoneally (IP) and intragastric route (IG). The UDE-treated mice were compared with the PYR + SDZ treatment. The histopathological changes, cyst count, total antioxidant capacity (TAC), malondialdehyde (MDA) assay, and serum INF-γ were also evaluated. RESULTS: In the acute toxoplasmosis, UDE by IP and IG administration significantly reduced the number of brain cysts by 93.74 and 92.55%, respectively, and increased the survival rate to 80% compared with 60% in untreated controls. In the chronic infection, cyst burden decreased at 88.2 and 83.4%, respectively, for IP and IG treatments. Moreover, UDE significantly increased INF- γ levels in acute and chronic toxoplasmosis. Tissue inflammatory lesions were reduced in the UDE-treated subgroups compared to the untreated group. UDE treatment significantly reduced MDA levels and elevated TAC in both acute and chronic infections. CONCLUSION: The results show that U. dioica possesses significant immunostimulant and antioxidant activity with a higher cyst reduction in the brain during acute toxoplasmosis. Further studies are required to investigate the fractionations of UDE against T. gondii and its combination with other standard drugs.


Assuntos
Toxoplasma , Toxoplasmose Animal , Toxoplasmose , Urtica dioica , Animais , Camundongos , Antioxidantes/farmacologia , Infecção Persistente , Toxoplasmose/parasitologia , Imunidade , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/parasitologia
3.
Parasite Immunol ; 45(12): e13014, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37807942

RESUMO

This study investigated a 'de Novo' medicinal herb, Ferula asafetida (FA), against toxoplasma encephalitis either alone or combined with spiramycin (SP). Female Swiss-Webster mice (n = 72) were divided into three batches. Batch-I received no DMS to serve as an immunocompetent control, batch-II was immune-suppressed with the DMS (0.25 mg/g/day) for 14 days pre-infection, whilst batch-III was immune-suppressed with the DMS on the same day of infection. All experimental mice were inoculated with Toxoplasma gondii ME49 cysts (n = 75). Each batch was split into four subgroups: Mono-SP, mono-FA, combined drug (SP + FA), or neither. Therapies were administered on day zero of infection in batches (I and II) and 35 days post-infection in batch (III). Treatments lasted for 14 days, and mice were sacrificed 60 days post-infection. Histopathological changes, cysts load, and CD4 and CD8 T-cells were counted in brain tissues. The cyst-load count in mice receiving SP + FA was significantly (p < .0001) the least compared to the mono treatments in all protocols. Interestingly, the combined therapy demolished the T-cell subsets to zero in immunocompetent and immunocompromised infected mice. In conclusion, F. asafetida might be a powerfully natural, safe vehicle of SP in the digestive system and/or across the brain-blood barrier to control toxoplasmosis even through immunodeficient conditions.


Assuntos
Encefalite , Ferula , Espiramicina , Toxoplasma , Toxoplasmose Animal , Toxoplasmose Cerebral , Feminino , Camundongos , Animais , Espiramicina/uso terapêutico , Encéfalo , Toxoplasmose Animal/tratamento farmacológico , Encefalite/tratamento farmacológico , Encefalite/patologia
4.
BMC Vet Res ; 19(1): 110, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542292

RESUMO

BACKGROUND: Toxoplasma gondii is traditionally known as a parasite of felids, with possible infection in intermediate hosts such as dogs and humans, and thus a disease of public health significance. Published data on the prevalence of toxoplasmosis in dogs and cats in Singapore is scanty, and this paper documents a suspect clinical case of toxoplasmosis in a free-roaming puppy trapped from an offshore island of Singapore. CASE PRESENTATION: A 12-week-old puppy presented with hindlimb weakness and sarcopenia, with rapidly progressing ascending paralysis and respiratory distress, one week after trapping. Toxoplasmosis was suspected after indirect fluorescence antibody testing (IFAT) revealed anti-T. gondii antibodies. The puppy responded quickly to clindamycin treatment and was discharged from hospital after 10 days. CONCLUSION: While rare and undocumented, veterinary clinicians in Singapore are advised to also include toxoplasmosis infection as a differential diagnosis in dogs presenting with similar clinical signs. This is especially so for dogs which have access to the outdoors.


Assuntos
Doenças do Gato , Doenças do Cão , Toxoplasma , Toxoplasmose Animal , Humanos , Cães , Animais , Gatos , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/epidemiologia , Doenças do Gato/diagnóstico , Doenças do Gato/tratamento farmacológico , Doenças do Gato/epidemiologia , Singapura , Doenças do Cão/diagnóstico , Doenças do Cão/tratamento farmacológico , Doenças do Cão/epidemiologia , Anticorpos Antiprotozoários , Estudos Soroepidemiológicos
5.
Trop Biomed ; 40(1): 115-123, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37356011

RESUMO

Toxoplasma gondii, the etiologic agent of toxoplasmosis, infects about 30 - 50% of the world population. The currently available anti-Toxoplasma agents have serious limitations. The present study aimed to investigate the effects of two antimalarials; buparvaquone (BPQ) and chloroquine (CQ), on immunocompromised mice with chronic cerebral toxoplasmosis, using spiramycin as a reference drug. The assessed parameters included the estimation of mortality rates (MR) among mice of the different study groups, in addition to the examination of the ultrastructural changes in the brain tissues by transmission electron microscopy. The results showed that only CQ treatment could decrease the MR significantly with zero deaths, while both spiramycin and BPQ caused an insignificant reduction of MR compared to the infected non-treated group. All the used drugs decreased the number of mature ruptured cysts significantly compared to the infected non-treated group, while only CQ increased the number of atrophic and necrotic cysts significantly. Furthermore, both spiramycin and BPQ improved the microvasculopathy and neurodegeneration accompanying the infection with different degrees of reactive astrocytosis and neuronal damage with the best results regarding the repair of the microvascular damage with less active glial cells, and normal neurons in the CQ-treated group. In conclusion, this study sheds light on CQ and its excellent impact on treating chronic cerebral toxoplasmosis in an immunocompromised mouse model.


Assuntos
Cistos , Espiramicina , Toxoplasma , Toxoplasmose Animal , Toxoplasmose Cerebral , Animais , Camundongos , Espiramicina/farmacologia , Espiramicina/uso terapêutico , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Modelos Animais de Doenças , Toxoplasmose Animal/tratamento farmacológico
6.
Parasitol Res ; 122(4): 927-937, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36786888

RESUMO

Toxoplasmosis is an immunologically complex disease, particularly in immunocompromised patients. Although there are several therapeutic regimens for such disease, the majority of them have many drawbacks. Therefore, it is of utmost importance to improve the current regimen in an effort to achieve a well-tolerated therapy while also enhancing the host immune response. Famous for their immunomodulatory effect, Lactobacillus delbrueckii and Lactobacillus fermentum probiotics were chosen to be evaluated in this study as an adjuvant therapy against the virulent RH Toxoplasma gondii (T. gondii) strain. Experimental mice were divided into control and treated groups. The control group was further subdivided into two groups: group I: 10 uninfected mice and group II: 20 infected untreated mice. The treated experimental group was subdivided into three groups (20 mice each); group III: sulfamethoxazole-trimethoprim (SMZ-TMP) treated, group IV: probiotics treated, and group V: SMZ-TMP combined with probiotics. The results obtained revealed that combined therapy increased survival rate and time up to 95% and 16 days, respectively, with an 82% reduction of tachyzoites and marked distortion, as detected by the scanning electron microscope (SEM). Additionally, combined therapy alleviated the severity and the extent of the inflammatory cells' infiltration, thereby reducing hepatocyte degeneration. Intriguingly, serum IF-γ level showed a significant increase to 155.92 ± 10.12 ng/L with combined therapy, reflecting the immunological role of the combined therapy. The current results revealed that probiotics have a high adjuvant potential in alleviating the impact of toxoplasmosis. Using probiotics as a synergistic treatment to modulate conventional therapy in systemic toxoplasmosis may gain popularity due to their low cost and current availability.


Assuntos
Lactobacillus delbrueckii , Limosilactobacillus fermentum , Probióticos , Toxoplasma , Toxoplasmose Animal , Toxoplasmose , Animais , Camundongos , Toxoplasmose/tratamento farmacológico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Toxoplasmose Animal/tratamento farmacológico
7.
Acta Trop ; 239: 106810, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36581225

RESUMO

Toxoplasmosis is a disease with a worldwide distribution and significant morbidity and mortality. In search of effective treatment, mefloquine (MQ) was repurposed and loaded with niosomes to treat acute and chronic phases of toxoplasmosis in experimental mice. Mice were orally inoculated with 20 cysts of Toxoplasma gondii (ME 49 strain) for the acute model of infection and 10 cysts for the chronic model of infection. Infected mice were dosed with MQ solution or MQ-niosomes at 50 mg/kg/day, starting from the second day post-infection (PI) (acute model) or the fifth week PI (chronic model), and this was continued for six consecutive days. The effects of MQ solution and MQ-niosomes were compared with a pyrimethamine/sulfadiazine (PYR/SDZ) dosing combination as mortality rates, brain cyst number, inflammatory score, and immunohistochemical studies that included an estimation of apoptotic cells (TUNEL assays). In the acute infection model, MQ solution and MQ-niosomes significantly reduced the mortality rate from 45% to 25 and 10%, respectively, compared with infected untreated controls, and decreased the number of brain cysts by 51.5% and 66.9%, respectively. In the chronic infection model, cyst reduction reached 80.9% and 12.3% for MQ solution and MQ-niosomes treatments, respectively. MQ-niosomes significantly decreased inflammation induced by acute or chronic T. gondii infection. Additionally, immunohistochemical analysis revealed that MQ solution and MQ-niosomes significantly increased the number of TUNEL-positive cells in brain tissue, indicative of induction of apoptosis. Collectively, these results indicate that MQ-niosomes may provide a useful delivery strategy to treat both acute and chronic toxoplasmosis.


Assuntos
Toxoplasma , Toxoplasmose Animal , Toxoplasmose , Animais , Camundongos , Mefloquina/uso terapêutico , Mefloquina/farmacologia , Lipossomos , Toxoplasmose/tratamento farmacológico , Pirimetamina/farmacologia , Sulfadiazina , Toxoplasmose Animal/tratamento farmacológico
8.
Parasitol Res ; 121(12): 3513-3521, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36163518

RESUMO

Chronic Toxoplasma gondii (T. gondii) infection has been revealed to be a risk factor for neuropsychiatric diseases, including anxiety. However, there is no intervention strategy. The present study aimed to investigate the protective effect of ß-glucan on T. gondii Wh6 strain-induced anxiety-like behavior in mice. The anxiety mouse model was established by infection with 10 cysts of the T. gondii Wh6 strain. ß-Glucan was intraperitoneally administered 2 weeks before infection. Open field and elevated plus maze tests were performed to assess anxiety-like behavior. In the open field test, Wh6-infected mice spent less time in the central zone and had fewer entries into the central zone. In the elevated plus maze test, the infection reduced the frequency and time of head entries in the open arms. These results showed that Wh6 causes anxiety-like behavior in mice. Interestingly, the administration of ß-glucan significantly ameliorated anxiety-like behavioral performance. The present study shows that ß-glucan can alleviate the anxiety-like behavior induced by chronic T. gondii infection in mice, which indicates that ß-glucan may be a potential drug candidate for treating T. gondii-related mental disorders, including anxiety.


Assuntos
Toxoplasma , Toxoplasmose Animal , Toxoplasmose , beta-Glucanas , Animais , Camundongos , Toxoplasmose/tratamento farmacológico , Ansiedade/tratamento farmacológico , Ansiedade/psicologia , Modelos Animais de Doenças , Toxoplasmose Animal/tratamento farmacológico
9.
Vet Dermatol ; 33(5): 435-439, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35644925

RESUMO

Toxoplasma gondii is a ubiquitous protozoan, for which felids are the definitive host. Immunocompromised individuals are susceptible to recrudescent toxoplasmosis. This case describes a 6-year-old, feline immunodeficiency virus-positive domestic short hair cat with feline atopic skin syndrome that developed fatal toxoplasmosis after treatment with oclacitinib for five months.


Toxoplasma gondii est un protozoaire ubiquitaire dont les félidés sont l'hôte définitif. Les personnes immunodéprimées sont sensibles à la toxoplasmose recrudescente. Ce cas décrit un chat domestique à poils courts de 6 ans, positif pour le virus de l'immunodéficience féline, atteint du syndrome atopique cutané félin, qui a développé une toxoplasmose mortelle après un traitement à l'oclacitinib pendant cinq mois.


Toxoplasma gondii es un protozoo ubicuo, cuyo huésped definitivo son los felinos. Las personas inmunocomprometidas son susceptibles a la toxoplasmosis recrudescente. Este caso describe un gato doméstico de pelo corto positivo para el virus de la inmunodeficiencia felina de 6 años de edad con síndrome de piel atópica felina, que desarrolló toxoplasmosis fatal después del tratamiento con oclacitinib durante cinco meses.


Toxoplasma gondii é um protozoário ubíquo para o qual os felídeos são o hospedeiro definitivo. Indivíduos imunocomprometidos são suscetíveis a toxoplasmose recrudescente. Este relato descreve um caso de um felino doméstico de pelo curto de seis anos de idade, positivo para o vírus da imunodeficiência felina, com síndrome atópica felina, que desenvolveu toxoplasmose fatal após tratamento com oclacitinib por cinco meses.


Assuntos
Doenças do Gato , Dermatite Atópica , Vírus da Imunodeficiência Felina , Toxoplasma , Toxoplasmose Animal , Animais , Doenças do Gato/tratamento farmacológico , Gatos , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/veterinária , Pirimidinas , Sulfonamidas , Toxoplasmose Animal/tratamento farmacológico
10.
Acta Trop ; 232: 106508, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35568067

RESUMO

BACKGROUND: Toxoplasmosis is a deleterious parasitic disease with harmful impact on both humans and animals. The present study was carried out to evaluate the antiparasitic effect of chloroquine (CQ), spiramycin (SP), and combination of both against the highly virulent RH HXGPRT (-) strain of Toxoplasma gondii (T. gondii) and to explore the mechanisms underlying such effect. METHODS: We counted the tachyzoites in the peritoneal fluid and liver smears of mice and performed scanning and transmission electron microscopy and immunofluorescence staining of tachyzoites. Moreover, relative caspase 3 gene expression was measured by real time polymerase chain reaction of liver tissues and immunoassay of anti-apoptotic markers [B cell lymphoma-2 (Bcl-2) and X-chromosome linked inhibitor of apoptosis (XIAP)] and interferon gamma (IFN-γ) was done in liver tissues by ELISA. In addition, we estimated serum levels of aspartate transaminase (AST) and alanine transaminase (ALT) and performed histopathological examination of liver sections for scoring of inflammation. RESULTS: We found that both CQ and CQ/SP combination significantly reduced parasitic load in the peritoneal fluid and liver smears, induced apical disruption of tachyzoites, triggered host cell apoptosis through elevation of relative caspase 3 gene expression and suppression of both Bcl-2 and XIAP. Also, they upregulated IFN-γ level, reduced serum AST and ALT, and ameliorated liver inflammation. CONCLUSIONS: Either of CQ and CQ/SP combination was more effective than SP alone against T. gondii with the CQ/SP combination being more efficient. Therefore, adding CQ to other anti-Toxoplasma therapeutic regimens may be considered in future research.


Assuntos
Toxoplasma , Toxoplasmose Animal , Alanina Transaminase , Animais , Antiparasitários/uso terapêutico , Aspartato Aminotransferases , Caspase 3/farmacologia , Caspase 3/uso terapêutico , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Inflamação/tratamento farmacológico , Interferon gama/genética , Interferon gama/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/uso terapêutico , Toxoplasma/genética , Toxoplasmose Animal/tratamento farmacológico
11.
Pathog Glob Health ; 116(2): 107-118, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34420500

RESUMO

Toxoplasmosis is a zoonotic disease of major significant perspectives in public health and veterinary medicine. So far, the available drugs control only the active infection, once the parasite encysts in the tissues, they lose their efficacy. Cytokines; IFN-γ and IL-10, play a critical role in the modulation of toxoplasmic encephalitis and neuro-inflammation in chronic toxoplasmosis. Antiretroviral protease inhibitors applied in the treatment of acquired immunodeficiency syndrome, revealed activity against multiple parasites. Aluvia (lopinavir/ritonavir) (L/R); an aspartyl protease inhibitor, had efficiently treated T. gondii RH strain infection. We investigated the potential activity of L/R against experimental T. gondii infection with a cystogenic Me49 strain in mice, considering the role of IFN-γ and IL-10 in the neuropathology versus pyrimethamine-sulfadiazine combination therapy. Three aluvia regimens were applied; starting on the day of infection (acute phase), 2-week PI (early chronic phase) and eight weeks PI (late chronic phase). L/R reduced the brain-tissue cyst burden significantly in all treatment regimens. It impaired the parasite infectivity markedly in the late chronic phase. Ultrastructural changes were detected in Toxoplasma cyst membrane and wall, bradyzoite membrane and nuclear envelope. The signs of bradyzoite paraptosis and cytoplasmic lipid droplets were observed. L/R had significantly reduced the brain-homogenate levels of IFN-γ and IL-10 in its three regimens however, they could not reach the normal level in chronic phases. Cerebral hypercellularity, perivascular inflammatory response, lymphoplasmacytic infiltrates and glial cellular reaction were ameliorated by L/R treatment. Herein, L/R was proved to possess promising preventive and therapeutic perspectives in chronic cerebral toxoplasmosis.


Assuntos
Inibidores da Protease de HIV , Toxoplasma , Toxoplasmose Animal , Toxoplasmose Cerebral , Animais , Inibidores da Protease de HIV/farmacologia , Inibidores da Protease de HIV/uso terapêutico , Interleucina-10 , Camundongos , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/prevenção & controle , Toxoplasmose Cerebral/tratamento farmacológico , Toxoplasmose Cerebral/prevenção & controle
12.
Molecules ; 26(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34770802

RESUMO

The quinolone decoquinate (DCQ) is widely used in veterinary practice for the treatment of bacterial and parasitic infections, most notably, coccidiosis in poultry and in ruminants. We have investigated the effects of treatment of Toxoplasma gondii in infected human foreskin fibroblasts (HFF) with DCQ. This induced distinct alterations in the parasite mitochondrion within 24 h, which persisted even after long-term (500 nM, 52 days) treatment, although there was no parasiticidal effect. Based on the low half-maximal effective concentration (IC50) of 1.1 nM and the high selectivity index of >5000, the efficacy of oral treatment of pregnant mice experimentally infected with T. gondii oocysts with DCQ at 10 mg/kg/day for 5 days was assessed. However, the treatment had detrimental effects, induced higher neonatal mortality than T. gondii infection alone, and did not prevent vertical transmission. Thus, three quinoline-O-carbamate derivatives of DCQ, anticipated to have better physicochemical properties than DCQ, were assessed in vitro. One such compound, RMB060, displayed an exceedingly low IC50 of 0.07 nM, when applied concomitantly with the infection of host cells and had no impact on HFF viability at 10 µM. As was the case for DCQ, RMB060 treatment resulted in the alteration of the mitochondrial matrix and loss of cristae, but the changes became apparent at just 6 h after the commencement of treatment. After 48 h, RMB060 induced the expression of the bradyzoite antigen BAG1, but TEM did not reveal any other features reminiscent of bradyzoites. The exposure of infected cultures to 300 nM RMB060 for 52 days did not result in the complete killing of all tachyzoites, although mitochondria remained ultrastructurally damaged and there was a slower proliferation rate. The treatment of mice infected with T. gondii oocysts with RMB060 did reduce parasite burden in non-pregnant mice and dams, but vertical transmission to pups could not be prevented.


Assuntos
Antiprotozoários/farmacologia , Carbamatos , Decoquinato/farmacologia , Quinolinas/farmacologia , Toxoplasma/efeitos dos fármacos , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/parasitologia , Animais , Antiprotozoários/química , Carbamatos/química , Decoquinato/análogos & derivados , Decoquinato/química , Modelos Animais de Doenças , Feminino , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Camundongos , Estrutura Molecular , Oocistos/efeitos dos fármacos , Gravidez , Quinolinas/química , Toxoplasma/ultraestrutura
13.
Ultrastruct Pathol ; 45(6): 376-383, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34595988

RESUMO

Over one billion people worldwide are expected to have Toxoplasma gondii infection with anonymous health problems. Available therapies are ineffective for persistent chronic toxoplasmosis. So, there is an imperative need for effective therapies to eliminate chronic tissue stage. In this study, we aimed to assess the effect of a drug combination of atovaquone and proguanil hydrochloride in the treatment of experimental chronic toxoplasmosis. Fifty Swiss Webster mice were used in the study. Forty mice were infected with Me49 type II cystogenic Toxoplasma gondii strain and allocated into four groups: infected untreated (vehicle-administered), infected and treated with cotrimoxazole (CTX) 370 mg/kg/day, infected and treated with atovaquone (ATV) 100 mg/kg/day, and infected and treated with atovaquone/proguanil (ATV/PROG) 50 mg/kg/day. An additional group of uninfected mice was used as an uninfected control group. Drug treatment was initiated 8 weeks post-infection and continued for two weeks. All mice were sacrificed 12 weeks post-infection. Parasitological and histopathological parameters were assessed. Toxoplasma gondii cysts recovered from brain tissue homogenates of both infected untreated and ATV/PROG-treated groups were examined by scanning electron microscopy. Combined ATV/PROG treatment demonstrated a significant reduction of Toxoplasma gondii cyst count in brain tissue (a reduction rate of 84.87%) compared to untreated group (P < .001). Brain tissues obtained from ATV/PROG treated group showed reduction of inflammatory infiltrate and marked attenuation and deformation of recovered Toxoplasma gondii cysts. We conclude that ATV/PROG drug combination could offer a potential drug therapy for Toxoplasma gondii chronic cystic stage.


Assuntos
Naftoquinonas , Toxoplasma , Toxoplasmose Animal , Animais , Atovaquona/farmacologia , Encéfalo , Camundongos , Proguanil , Toxoplasmose Animal/tratamento farmacológico
14.
Antimicrob Agents Chemother ; 65(10): e0100321, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34339265

RESUMO

Individuals infected with Toxoplasma gondii are prone to psychobehavioral disorders, most notably schizophrenia and bipolar disorder. Valproic acid reportedly inhibits the proliferation of T. gondii tachyzoites in vitro. However, animals treated with the drug neither lived longer during acute infection nor had fewer brain cysts upon chronic infection. In this study, a quantitative real-time PCR (qPCR) method was applied to quantify copy numbers of BAG1 (a bradyzoite-specific protein), REP529 DNA (a repetitive DNA fragment of the parasite), and SAG1 (a highly expressed tachyzoite-specific surface protein) in the brains of chronically infected mice treated with valproic acid. The treatment inhibited the infection and decreased BAG1, SAG1, and REP529 copy numbers in mice brains (P < 0.0001), comparable to the effects of trimethoprim-sulfamethoxazole (TMP-SMZ), the common medication for toxoplasmosis treatment. Moreover, valproic acid decreased brain tumor necrosis factor alpha (TNF-α) expression (P < 0.0001) comparably to TMP-SMZ. Histological examination of mouse brains showed marked reductions in cyst establishment, perivascular infiltration of lymphocytes, and glial nodules to the same levels as those in the TMP-SMZ group. Our results provide direct evidence for the efficacy of valproic acid, a mood-stabilizing and antipsychotic drug, against chronic Toxoplasma infection. These results might help modulate therapeutic regimens for neuropsychiatric patients and aid in the design of more effective anti-Toxoplasma drugs.


Assuntos
Encefalite , Toxoplasma , Toxoplasmose Animal , Toxoplasmose , Animais , Encéfalo , Humanos , Camundongos , Toxoplasmose/tratamento farmacológico , Toxoplasmose Animal/tratamento farmacológico , Ácido Valproico/farmacologia
15.
Acta Parasitol ; 66(4): 1472-1479, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34050875

RESUMO

PURPOSE: Nowadays, due to the lack of an effective vaccine to prevent the toxoplasmosis, chemotherapy with the combination of pyrimethamine and sulfadiazine is considered as the "gold standard" treatment for toxoplasmosis. Recent reports have exhibited that these synthesized chemical drugs are associated with some serious side effects. The present study aims to evaluate the prophylactic effects of copper nanoparticles (CuNPs) green synthesized by Capparis spinosa fruit methanolic extract alone and combined with atovaquone against chronic toxoplasmosis induced by the Tehran strain of Toxoplasma gondii in mice METHODS: Mice were then orally administrated with CuNPs at the doses of 2 and 4 mg/kg/day and in combined with atovaquone 50 mg/kg for 14 days. Male BALB/c mice were divided into two seven groups include C1 (non-treated non-infected); C2 (treated with normal saline); C3 (Infected mice treated with atovaquone 100 mg/kg/day); Ex1 (treated with CuNPs 2 mg/kg/day); Ex2 (treated with CuNPs 4 mg/kg/day); Ex3 (treated with CuNPs 2 mg/kg/day + atovaquone 50 mg/kg/day); Ex3 (treated with CuNPs 4 mg/kg/day + atovaquone 50 mg/kg/day). On the 15th day, the mice were infected with the intraperitoneal inoculation of 20-25 tissue cysts from the Tehran strain of T. gondii. The mean numbers of brain tissue cysts and the mRNA levels of IL-12, IFN-γ, and inducible nitric oxide synthase (iNOS) in mice of each tested group were measured. RESULTS: CuNPs were green synthesized by C. spinosa methanolic extract. Scanning electron microscopy showed that the particle size of CuNPs was 17 and 41 nm with maximum peak at the wavelength of 414 nm. The mean number of T. gondii tissue cysts in mice of tested groups of Ex1, Ex2, Ex3, and Ex4, significantly decreased as a dose-dependent response compared with control group. Moreover, in similar to the control group C3, no T. gondii tissue cysts was observed in mice of experimental group Ex3 and Ex4. The mRNA levels of IFN-γ, IL-12, and iNO was measured in mice of all tested groups. The mRNA levels of IFN-γ, IL-12, and iNO was increased in all mice of experimental groups in comparison with the control group C2; however, a significant enhancement was detected in mRNA level of IFN-γ, IL-12, and iNO in the tested groups of Ex3 and Ex4 when compared with control group C3. CONCLUSION: The obtained results revealed the high potency of CuNPs alone and combined with atovaquone to prevent toxoplasmosis in mice. Although, the prophylactic effects of CuNPs and other properties, such as improved cellular immunity and low toxicity, are positive topics; however, more studies are required to approve these findings especially in clinical settings.


Assuntos
Nanopartículas , Toxoplasma , Toxoplasmose Animal , Toxoplasmose , Animais , Cobre , Irã (Geográfico) , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/prevenção & controle
16.
Pol J Vet Sci ; 24(1): 51-61, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33847093

RESUMO

Toxoplasmosis is one of the most important protozoa zoonotic diseases worldwide. The present study describes the clinical, seroprevalence findings with ocular toxoplasmosis and the outcome of medicinal treatment of these cats. This study was carried out on 105 cats with various ocular signs, no historical evidence of ocular trauma or drug/vaccine exposure for at least 3 months prior to admission, and without clinical or laboratory evidence of other systemic diseases. Complete case history, physical and ophthalmic examinations were carried out. The seroprevalence of Toxoplasma gondii antibodies was determined using the Toxoplasma Ab Rapid Test and Enzyme Linked Immunosorbent Assay. Out of 105 examined cats with ocular lesions, 60 cats representing 57.14% were seropositive to T. gondii. Out of these 60 cats, 15 cats (25%) had bilateral ocular abnormalities, 25 cats (41.67%) had right-sided ocular disease, and 20 cats (33.33%) had left-sided ocular disease. There were 38 cats (63.33%) with anterior uveitis, 12 cats (20%) with posterior segment involvement, 5 cats (8.33%) with anterior uveitis and anterior chamber abnormalities, 3 cats (5%) with corneal abnormalities and 2 cats (3.34%) with anterior uveitis with concurrent corneal involvement. There was a significant difference in the index values of IgM and IgG between seropositive and seronegative cats with T. gondii antibodies (p⟨0.05). There was no significant difference between the different ages, genders and breeds of cats with seroprevalence of T. gondii antibodies as well as between the age and total number of cats with seropositive and seronegative T. gondii. Out of 60 treated cats, 28 cats (46.7%), 25 cats (41.7%) and 7 cats (11.6%) showed complete, partial and poor response to treatment, respectively. In conclusion, cats showing ocular signs without obvious etiology should be examined serologically for toxoplasmosis and the seropositive cats should be treated with both specific topical and systemic treatments.


Assuntos
Doenças do Gato/parasitologia , Oftalmopatias/veterinária , Toxoplasmose Animal/patologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Doenças do Gato/diagnóstico , Doenças do Gato/tratamento farmacológico , Gatos , Clindamicina/uso terapêutico , Oftalmopatias/diagnóstico , Oftalmopatias/tratamento farmacológico , Oftalmopatias/parasitologia , Midriáticos/administração & dosagem , Midriáticos/uso terapêutico , Soluções Oftálmicas , Inibidores da Síntese de Proteínas/uso terapêutico , Combinação Tobramicina e Dexametasona/uso terapêutico , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/tratamento farmacológico , Tropicamida/uso terapêutico
17.
Vet Parasitol Reg Stud Reports ; 23: 100542, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33678395

RESUMO

Toxoplasma gondii, an obligatory intracellular protozoan parasite infecting warm-blooded animals, can cause toxoplasmosis, a major zoonosis. A male neutered, domestic cat was referred to the Hebrew University Veterinary Teaching Hospital due to dyspnea after long term treatment with cyclosporine for obsessive self-grooming and pruritis. After thorough diagnostics, including non - invasive imaging, broncho-alveolar lavage, blood serology, hematology and biochemistry, and evaluation of the aspirated fluid components, a severe pneumonia and abdominal effusion were detected with observation of free tachyzoites under light microscopy from lavage fluids. PCR and DNA sequencing of broncho-alveolar lavage was positive for T. gondii. Despite aggressive treatment with antibiotics, oxygen supplementation and T. gondii specific antimicrobials, the cat died. It is suggested that potential candidates for cyclosporine be screened for T. gondii antibodies, kept entirely indoors and not fed uncooked meat in order to prevent exposure to T. gondii infection.


Assuntos
Doenças do Gato , Ciclosporinas , Toxoplasmose Animal , Animais , Doenças do Gato/diagnóstico , Doenças do Gato/tratamento farmacológico , Doenças do Gato/parasitologia , Gatos , Ciclosporinas/uso terapêutico , Hospitais Veterinários , Hospitais de Ensino , Masculino , Toxoplasma/genética , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/tratamento farmacológico
18.
J Ethnopharmacol ; 273: 114019, 2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-33716084

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sulfadiazine and pyrimethamine are the two drugs used as part of the standard therapy for toxoplasmosis, however; they may cause adverse side effects and fail to prevent relapse in many patients, rendering infected individuals at risk of reactivation upon becoming immunocompromised. Extracts from various parts of Annona muricata have been widely used medicinally for the management, control and/or treatment of several human diseases, acting against parasites that cause diseases in humans. AIM OF THE STUDY: This study was performed to investigate the action of the ethanolic extract of A. muricata (EtOHAm) and its fractions in the control of the apicomplexan parasite Toxoplasma gondii in vitro and in vivo, and the effect of EtOHAm on the inflammatory response and lipid profile alteration induced by in vivo T. gondii infection. MATERIALS AND METHODS: The cytotoxicity of EtOHAm and its fractions ethyl acetate (EtOAcAm), n-butanol (BuOHAm), aqueous (H2OAm), hexane (HexAm) and dichloromethane (CH2Cl2Am) was evaluated in NIH/3T3 fibroblasts using the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The cells were infected with T. gondii, treated with the extracts, and parasite proliferation was analyzed. For the in vivo experiments, C57BL/6 mice were orally infected with T. gondii and, treated with different concentrations of extract fractions that were effective in vitro (EtOHAm, EtOAcAm, HexAm and CH2Cl2Am). Tissue parasitism, histological alterations, systemic cytokine and lipid profile were investigated. RESULTS: EtOHAm, EtOAcAm, BuOHAm, H2OAm presented low cytotoxicity until doses of 200 µg/mL, while HexAm and CH2Cl2Am presented toxicity from doses of 100µg/mL. EtOHAm, HexAm and CH2Cl2Am decreased the parasitism in vitro, presenting a therapeutic index of 2.62, 2.44, and 2.96, respectively. In vivo, EtOHAm, HexAm and CH2Cl2Am improved the survival rate of infected animals, however, only EtOHAm was able to decrease the parasitism in the small intestine and lung. Additionally, EtOHAm decreased the systemic interferon (IFN)-γ and tumor necrosis factor (TNF) systemically in infected mice, and was able to maintain the triglycerides and very-low-density lipoprotein (VLDL) lipid fractions at similar levels to uninfected animals. Although treatment with EtOHAm could not control the inflammation induced by oral infection in the tissues analyzed, it was able to preserve the number of goblet cells in the small intestine. CONCLUSIONS: Ethanolic A. muricata leaf extract could be considered as a good candidate for the development of a complementary/alternative therapy against toxoplasmosis, and also as an anti-inflammatory alternative for decreasing TNF and IFN-γ concentrations and lipid fractions in specific diseases.


Assuntos
Annona/química , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Toxoplasma/efeitos dos fármacos , Toxoplasmose Animal/tratamento farmacológico , Animais , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Fitoterapia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química
19.
Acta Parasitol ; 66(3): 827-836, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33555553

RESUMO

PURPOSES: Evaluate the effect of auranofin on the early and late stages of chronic infection with Toxoplasma gondii avirulent ME49 strain. METHODS: Swiss albino mice were orally inoculated with 10 cysts of Toxoplasma gondii, and orally treated with auranofin or septazole in daily doses of 20 mg/kg or 100 mg /kg, respectively, for 30 days. Treatment began either on the same day of infection and mice were sacrificed at the 60th day postinfection or the treatment started after 60 days of infection and mice were sacrificed at the 90th day postinfection. RESULTS: Auranofin significantly reduced the brain cyst burden and inflammatory reaction at both stages of infection compared to the infected non-treated control. More remarkably, auranofin significant reduced the brain cyst burden in the late stage, while septazole failed. Hydrogen peroxide level was significantly increased in the brain homogenate of mice treated with auranofin only at the early stage of infection. Ultrastructral studies revealed that the anti-Toxoplasma effect of auranofin is achieved by changing the membrane permeability and inducing apoptosis. CONCLUSIONS: Thus, auranofin could be an alternative for the standard treatment regimen of toxoplasmosis and these results are considered another achievement for the drug against parasitic infection. Being a FDA-approved drug, it can be rapidly evaluated in clinical trials.


Assuntos
Toxoplasma , Toxoplasmose Animal , Toxoplasmose Cerebral , Animais , Auranofina/farmacologia , Auranofina/uso terapêutico , Encéfalo , Reposicionamento de Medicamentos , Camundongos , Toxoplasmose Animal/tratamento farmacológico
20.
Parasitol Res ; 120(2): 593-603, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33415386

RESUMO

Toxoplasma gondii is a widespread zoonotic protozoan that infects most species of mammals and birds, including poultry. This study aimed to investigate the course of T. gondii infection and the efficacy of diclazuril and Artemisia annua in preventing infection in experimentally infected chickens. Seventy-five 1-month-old chickens, female and male, were randomly divided into five groups (n = 15 each) as follows: (1) uninfected untreated (negative control, NC); (2) infected with T. gondii genotype II/III isolated from a wild cat (group WC); (3) infected with T. gondii genotype II isolated from a domestic cat (group DC); (4) infected with T. gondii domestic cat strain and treated with the anticoccidial diclazuril (group DC-D); and (5) infected with T. gondii domestic cat strain and treated with the medicinal plant Artemisia annua (group DC-A). Clinical signs, body temperature, mortality rate, weight gain, feed conversion ratio, hematological parameters, and the presence of T. gondii-specific IgY antibodies were recorded in all groups. Five chickens per group were euthanized 28 days post-infection (p.i.) and their brains, hearts, and breast muscle tested for T. gondii by mouse bioassay and polymerase chain reaction (PCR). No clinical signs related to the experimental infection were observed throughout the study period. T. gondii-specific antibodies were detected by day 28 p.i., but not in all infected chickens. Overall, T. gondii DNA was detected (bioassay or tissue digests) in all infected and untreated chickens (10/10), while viable parasite (bioassay) was isolated from 7 out of 10 chickens. The parasite was most frequently identified in the brain (7/10). There were no differences in the T. gondii strains regarding clinical infection and the rate of T. gondii detection in tissues. However, higher antibody titers were obtained in chickens infected with T. gondii WC strain (1:192) comparing with T. gondii DC strain (1:48). A. annua reduced replication of the parasite in 3 out of 5 chickens, while diclazuril did not. In conclusion, broiler chickens were resistant to clinical toxoplasmosis, irrespective of the strain (domestic or wild cat strain). The herb A. annua presented prophylactic efficacy by reduced parasite replication. However, further studies are required aiming at the efficacy of diclazuril and A. annua for the prevention of T. gondii infection in chickens using quantitative analysis methods.


Assuntos
Anticorpos Antiprotozoários/imunologia , Artemisia annua , Coccidiostáticos/farmacologia , Nitrilas/farmacologia , Doenças das Aves Domésticas/prevenção & controle , Toxoplasma/imunologia , Toxoplasmose Animal/prevenção & controle , Triazinas/farmacologia , Animais , Encéfalo/parasitologia , Gatos , Galinhas , Feminino , Genótipo , Coração/parasitologia , Masculino , Camundongos , Músculos Peitorais/parasitologia , Plantas Medicinais , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/parasitologia , Distribuição Aleatória , Soroconversão , Distribuição Tecidual , Toxoplasma/genética , Toxoplasma/fisiologia , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/parasitologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...