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1.
Parasitol Res ; 123(1): 65, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38133827

RESUMO

The selection process for advanced therapies in patients with inflammatory bowel diseases (IBDs) must prioritize safety, especially when considering new biologic agents or oral molecule modulators. In C57BL/6 mice, oral infection with Toxoplasma gondii induces intestinal inflammation through excessive tumor necrosis factor (TNF) production, making TNF neutralization a potential therapeutic intervention. Considering this, the present study aimed to evaluate the therapeutic effects of BmooMP-α-I, a snake venom metalloprotease isolated from Bothrops moojeni, which could promote TNF hydrolysis, in treating T. gondii-induced ileitis. The results showed that C57BL/6 mice orally infected with 50 cysts of T. gondii from the Me49 strain and treated with BmooMP-α-I exhibited prolonged survival and improved morbidity scores. Additionally, the treatment ameliorated both the macroscopic and microscopic aspects of the intestine, reduced macrophage influx, and decreased the production of inflammatory mediators by mesenteric lymph node cells. These findings provide compelling experimental evidence supporting the ability of BmooMP-α-I to alleviate ileal inflammation. Considering that the currently available therapeutic protocols are not completely effective and often result in side effects, the exploration of alternative strategies involving novel therapeutic agents, as demonstrated in this study, has the potential to significantly enhance the quality of life for patients suffering from inflammatory bowel diseases.


Assuntos
Doenças Inflamatórias Intestinais , Toxoplasma , Toxoplasmose , Humanos , Animais , Camundongos , Qualidade de Vida , Camundongos Endogâmicos C57BL , Inflamação/tratamento farmacológico , Toxoplasmose/patologia , Metaloproteases , Modelos Teóricos
2.
Front Immunol ; 14: 1243480, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37915581

RESUMO

Introduction: Toxoplasma gondii is the etiologic agent of toxoplasmosis, a disease that affects about one-third of the human population. Most infected individuals are asymptomatic, but severe cases can occur such as in congenital transmission, which can be aggravated in individuals infected with other pathogens, such as HIV-positive pregnant women. However, it is unknown whether infection by other pathogens, such as Trypanosoma cruzi, the etiologic agent of Chagas disease, as well as one of its proteins, P21, could aggravate T. gondii infection. Methods: In this sense, we aimed to investigate the impact of T. cruzi and recombinant P21 (rP21) on T. gondii infection in BeWo cells and human placental explants. Results: Our results showed that T. cruzi infection, as well as rP21, increases invasion and decreases intracellular proliferation of T. gondii in BeWo cells. The increase in invasion promoted by rP21 is dependent on its binding to CXCR4 and the actin cytoskeleton polymerization, while the decrease in proliferation is due to an arrest in the S/M phase in the parasite cell cycle, as well as interleukin (IL)-6 upregulation and IL-8 downmodulation. On the other hand, in human placental villi, rP21 can either increase or decrease T. gondii proliferation, whereas T. cruzi infection increases T. gondii proliferation. This increase can be explained by the induction of an anti-inflammatory environment through an increase in IL-4 and a decrease in IL-6, IL-8, macrophage migration inhibitory factor (MIF), and tumor necrosis factor (TNF)-α production. Discussion: In conclusion, in situations of coinfection, the presence of T. cruzi may favor the congenital transmission of T. gondii, highlighting the importance of neonatal screening for both diseases, as well as the importance of studies with P21 as a future therapeutic target for the treatment of Chagas disease, since it can also favor T. gondii infection.


Assuntos
Doença de Chagas , Toxoplasmose , Trypanosoma cruzi , Recém-Nascido , Humanos , Feminino , Gravidez , Placenta/patologia , Interleucina-8 , Toxoplasmose/patologia , Doença de Chagas/patologia , Proteínas Recombinantes
3.
Front Immunol ; 13: 822567, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572567

RESUMO

Toxoplasma gondii infects one-third of the world population. For decades, it has been considered a silent lifelong infection. However, chronically T. gondii-infected persons may present psychiatric and neurocognitive changes as anxiety, depression, and memory loss. In a model of long-term chronic infection, behavioral alterations parallel neuroinflammation and systemic high cytokine levels, and may reflect brain cyst load. Recent findings support that in chronic infection an active parasite-host interplay involves an immune-mediated control of tissue cysts. Here, we tested the idea that etiological treatment in chronic phase may add advantage to intrinsic immune-mediated cyst control and impact behavioral changes. Thus, we combined sulfadiazine-plus-pyrimethamine (S+P), the first-choice therapy for toxoplasmosis, to study the association of brain cyst load and biological processes related to the immune response (neuroinflammation, blood-brain barrier -BBB- disruption and serum cytokine levels), with behavioral and neurocognitive changes of long-term chronic infection. Female C57BL/6 mice (H-2b) were infected (5 cysts, ME-49 strain) and treated with S+P from 30 to 60 days postinfection (dpi), compared with vehicle (Veh)-treated and noninfected controls. At endpoints (pre-therapy, 30 dpi; S+P therapy, 60 dpi; after ceased therapy, 90 dpi), independent groups were subjected to behavioral tests, and brain tissues and sera were collected. Multiple behavioral and neurocognitive changes were detected in the early (30 dpi) and long-term (60 and 90 dpi) chronic infection. S+P therapy resolved locomotor alterations, anxiety, and depressive-like behavior, partially or transiently ameliorated hyperactivity and habituation memory loss. Analysis after therapy cessation showed that S+P therapy reduced the number of stimuli required for aversive memory consolidation. S+P therapy resulted in reduced brain cyst load, neuroinflammation and BBB disruption, and lowered systemic Th1-cytokine levels. Correlation analysis revealed association between IFNγ, TNF and MCP-1/CCL2 serum levels, brain cyst load and behavioral and neurocognitive alterations. Moreover, principal-component analysis (PCA-2D and 3D projections) highlighted distinction between clusters (noninfected; Veh-treated and S+P-treated infected). Thus, our data suggest that S+P therapy added gain to intrinsic brain cyst control and, direct or indirectly, ameliorated inflammation-related alterations, traits associated with behavioral and neurocognitive alterations.


Assuntos
Encéfalo , Pirimetamina , Sulfadiazina , Toxoplasmose , Animais , Encéfalo/parasitologia , Citocinas , Feminino , Inflamação/tratamento farmacológico , Transtornos da Memória/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Sulfadiazina/farmacologia , Sulfadiazina/uso terapêutico , Toxoplasmose/tratamento farmacológico , Toxoplasmose/patologia
4.
Tissue Cell ; 73: 101658, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34597888

RESUMO

Crosstalk between trophoblast and monocytes is essential for gestational success, and it can be compromised in congenital toxoplasmosis. Cell death is one of the mechanisms involved in the maintenance of pregnancy, and this study aimed to evaluate the role of trophoblast in the modulation of monocyte cell death in the presence or absence of Toxoplasma gondii infection. THP-1 cells were stimulated with supernatants of BeWo cells and then infected or not with T. gondii. The supernatants were collected and analyzed for the secretion of human Fas ligand, and cells were used to determine cell death and apoptosis, cell death receptor, and intracellular proteins expression. Cell death and apoptosis index were higher in uninfected THP-1 cells stimulated with supernatants of BeWo cells; however, apoptosis index was reduced by T. gondii infection. Macrophage migration inhibitory factor (MIF) and transforming growth factor (TGF)-ß1, secreted by BeWo cells, altered the cell death and apoptosis rates in THP-1 cells. In infected THP-1 cells, the expression of Fas/CD95 and secretion of FasL was significantly higher; however, caspase 3 and phosphorylated extracellular-signal-regulated kinase (ERK1/2) were downregulated. Results suggest that soluble factors secreted by BeWo cells induce cell death and apoptosis in THP-1 cells, and Fas/CD95 can be involved in this process. On the other hand, T. gondii interferes in the mechanism of cell death and inhibits THP-1 cell apoptosis, which can be associated with active caspase 3 and phosphorylated ERK1/2. In conclusion, our results showed that human BeWo trophoblast cells and T. gondii infection modulate cell death in human THP-1 monocyte cells.


Assuntos
Espaço Intracelular/metabolismo , Monócitos/patologia , Monócitos/parasitologia , Proteínas/metabolismo , Receptores de Morte Celular/metabolismo , Toxoplasmose/patologia , Trofoblastos/parasitologia , Caspase 3/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , Meios de Cultivo Condicionados/farmacologia , Regulação para Baixo/efeitos dos fármacos , Proteína Ligante Fas/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fatores Inibidores da Migração de Macrófagos/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Fosforilação/efeitos dos fármacos , Células THP-1 , Trofoblastos/efeitos dos fármacos , Trofoblastos/metabolismo , Receptor fas/metabolismo
5.
Tissue Cell ; 72: 101544, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33892398

RESUMO

During pregnancy, Toxoplasma gondii can triggers serious manifestations and potentially affect the fetal development. In this scenario, differences in susceptibility of trophoblast cells to T. gondii infection might be evaluated in order to establish new therapeutic approaches capable of interfering in the control of fetal infection by T. gondii. This study aimed to evaluate the susceptibility of cytotrophoblast, syncytiotrophoblast and extravillous trophoblast cells to T. gondii infection. Our data demonstrate that HTR-8/SVneo cells (extravillous trophoblast cells) present higher susceptibility to T. gondii infection when compared to syncytiotrophoblast and cytotrophoblast cells, whereas syncytiotrophoblast was the cell type more resistant to the parasite infection. Also, cytotrophoblast and syncytiotrophoblast cells produced significantly more IL-6 than HTR-8/SVneo cells. On the other hand, HTR-8/SVneo cells showed higher ERK1/2 phosphorylation than cytotrophoblast and syncytiotrophoblast cells. ERK1/2 inhibition reduced T. gondii infection and increased IL-6 production in HTR-8/SVneo cells. Thus, it is plausible to conclude that the greater susceptibility of HTR-8/SVneo cells to infection by T. gondii is related to a higher ERK1/2 phosphorylation and lower levels of IL-6 in these cells compared to other cells, suggesting that these mediators may be important to favor the parasite infection in this type of trophoblastic population.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células Gigantes/patologia , Interleucina-6/biossíntese , Toxoplasmose/patologia , Trofoblastos/patologia , Trofoblastos/parasitologia , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Suscetibilidade a Doenças , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Humanos , Fosforilação , Regulação para Cima
6.
Sci Rep ; 11(1): 3137, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33542439

RESUMO

Ocular toxoplasmosis is the leading cause of posterior uveitis worldwide. We conducted an observational study of 262 consecutive individuals (n = 344 eyes) with ocular toxoplasmosis who were followed over a 34-month period. Most subjects were T. gondii IgG + /IgM- (n = 242; 92.4%; 317 eyes), and 140 eyes (40.7%) had active lesions. For eyes in which retinal lesions were active at recruitment and best-corrected visual acuity (BCVA) could be measured (n = 133), 21.0% (n = 28) remained blind (BCVA below 20/400) after inflammation resolved. In these eyes, atypical ocular toxoplasmosis (OR 4.99; 95% CI 1.14-22.85; p = 0.0330), macular lesion (OR 9.95; 95% CI 2.45-47.15; p = 0.0019) and any complication (OR 10.26; 95% CI 3.82-30.67; p < 0.0001) were associated with BCVA below 20/200. For eyes with only inactive lesions at recruitment and BCVA measured (n = 178), 28.1% (n = 50) were blind. In these eyes, having at least one lesion larger than one disc-diameter (OR 6.30; 95% CI 2.28-22.46; p = 0.0013) and macular lesion (OR 5.69; 95% CI 2.53-13.54; p < 0.0001) were associated with BCVA below 20/200. Older age (OR 1.02; 95% CI 1.00-1.05; p = 0.0493) and active disease at presentation (OR 4.74; 95% CI 1.95-12.91; p = 0.0011) were associated with recurrences. Additional clinical attention should be directed towards patients with risk factors for poor visual outcome.


Assuntos
Cegueira/patologia , Toxoplasma/patogenicidade , Toxoplasmose/patologia , Uveíte Posterior/patologia , Adolescente , Adulto , Fatores Etários , Idoso , Anticorpos Antiprotozoários/sangue , Antiprotozoários/uso terapêutico , Cegueira/tratamento farmacológico , Cegueira/imunologia , Cegueira/parasitologia , Brasil , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Pirimetamina/uso terapêutico , Recidiva , Retina/efeitos dos fármacos , Retina/imunologia , Retina/parasitologia , Retina/patologia , Fatores de Risco , Sulfadiazina/uso terapêutico , Toxoplasma/efeitos dos fármacos , Toxoplasma/crescimento & desenvolvimento , Toxoplasmose/tratamento farmacológico , Toxoplasmose/imunologia , Toxoplasmose/parasitologia , Resultado do Tratamento , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Uveíte Posterior/tratamento farmacológico , Uveíte Posterior/imunologia , Uveíte Posterior/parasitologia , Visão Ocular/efeitos dos fármacos , Acuidade Visual/efeitos dos fármacos
7.
Neurogastroenterol Motil ; 33(1): e13967, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32812313

RESUMO

BACKGROUND: Toxoplasma gondii infection causes intestinal inflammation and diarrhea indicating possible intestinal motor dysfunction. Anatomical studies have shown alterations in the colonic myenteric plexus, but it is unknown whether this impacts motility and therefore whether motility is a target for treatment. We determined whether colonic coordinated movements are compromised by toxoplasmic infection and how it is associated with anatomical changes. METHODS: Male Wistar rats were evaluated at 6, 12, 24, 48, and 72 hours and 30 days postinfection (dpi) and controls. Infected rats received orally 5 × 103 sporulated oocysts of strain ME-49 (genotype II) of T gondii. The colon was collected for anatomical analysis (including the myenteric plexus immunolabeled with HuC/D, nNOS, and ChAT) and motility analysis in vitro (conventional manometry). Fecal output was measured daily. KEY RESULTS: At 12 hours postinfection, T gondii caused hypertrophy of the muscularis externa layer of the distal colon. There was loss of total, nitrergic, and cholinergic myenteric neurons in the proximal colon at 30 day postinfection (dpi); however, only loss of cholinergic neurons was found in the distal colon. Contractile complexes in the middle and distal colon were longer in duration in infected animals, which was associated with slower migration of the colonic motor complex. However, gastrointestinal transit time and fecal pellet output remained unchanged during the T gondii infection. CONCLUSIONS AND INFERENCES: Toxoplasma gondii caused myenteric neuronal loss in the proximal and distal colon and altered the motility pattern in the middle and distal colon to a more propulsive phenotype.


Assuntos
Colo/inervação , Motilidade Gastrointestinal/fisiologia , Músculo Liso/inervação , Neurônios/patologia , Toxoplasmose/fisiopatologia , Animais , Colo/fisiopatologia , Músculo Liso/fisiopatologia , Plexo Mientérico , Complexo Mioelétrico Migratório/fisiologia , Ratos , Toxoplasmose/patologia
8.
Front Immunol ; 11: 595250, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240284

RESUMO

Trypanosoma cruzi and Toxoplasma gondii are two parasites than can be transmitted from mother to child through the placenta. However, congenital transmission rates are low for T. cruzi and high for T. gondii. Infection success or failure depends on complex parasite-host interactions in which parasites can alter host gene expression by modulating non-coding RNAs such as miRNAs. As of yet, there are no reports on altered miRNA expression in placental tissue in response to either parasite. Therefore, we infected human placental explants ex vivo by cultivation with either T. cruzi or T. gondii for 2 h. We then analyzed the miRNA expression profiles of both types of infected tissue by miRNA sequencing and quantitative PCR, sequence-based miRNA target prediction, pathway functional enrichment, and upstream regulator analysis of differentially expressed genes targeted by differentially expressed miRNAs. Both parasites induced specific miRNA profiles. GO analysis revealed that the in silico predicted targets of the differentially expressed miRNAs regulated different cellular processes involved in development and immunity, and most of the identified KEGG pathways were related to chronic diseases and infection. Considering that the differentially expressed miRNAs identified here modulated crucial host cellular targets that participate in determining the success of infection, these miRNAs might explain the differing congenital transmission rates between the two parasites. Molecules of the different pathways that are regulated by miRNAs and modulated during infection, as well as the miRNAs themselves, may be potential targets for the therapeutic control of either congenital Chagas disease or toxoplasmosis.


Assuntos
Doença de Chagas , Regulação da Expressão Gênica/imunologia , MicroRNAs/imunologia , Placenta , Toxoplasma/imunologia , Toxoplasmose , Trypanosoma cruzi/imunologia , Doença de Chagas/imunologia , Doença de Chagas/patologia , Feminino , Humanos , Placenta/imunologia , Placenta/parasitologia , Placenta/patologia , Gravidez , Toxoplasmose/imunologia , Toxoplasmose/patologia
9.
Mem Inst Oswaldo Cruz ; 115: e200007, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935749

RESUMO

BACKGROUND: Behavioral and neurochemical alterations associated with toxoplasmosis may be influenced by the persistence of tissue cysts and activation of an immune response in the brain of Toxoplasma gondii-infected hosts. The cerebral extracellular matrix is organised as perineuronal nets (PNNs) that are both released and ensheath by some neurons and glial cells. There is evidences to suggest that PNNs impairment is a pathophysiological mechanism associated with neuropsychiatric conditions. However, there is a lack of information regarding the impact of parasitic infections on the PNNs integrity and how this could affect the host's behavior. OBJECTIVES: In this context, we aimed to analyse the impact of T. gondii infection on cyst burden, PNNs integrity, and possible effects in the locomotor activity of chronically infected mice. METHODS: We infected mice with T. gondii ME-49 strain. After thirty days, we assessed locomotor performance of animals using the open field test, followed by evaluation of cysts burden and PNNs integrity in four brain regions (primary and secondary motor cortices, prefrontal and somesthetic cortex) to assess the PNNs integrity using Wisteria floribunda agglutinin (WFA) labeling by immunohistochemical analyses. FINDINGS AND MAIN CONCLUSIONS: Our findings revealed a random distribution of cysts in the brain, the disruption of PNNs surrounding neurons in four areas of the cerebral cortex and hyperlocomotor behavior in T. gondii-infected mice. These results can contribute to elucidate the link toxoplasmosis with the establishment of neuroinflammatory response in neuropsychiatric disorders and to raise a discussion about the mechanisms related to changes in brain connectivity, with possible behavioral repercussions during chronic T. gondii infection.


Assuntos
Cerebelo/metabolismo , Matriz Extracelular/metabolismo , Neurônios Motores/citologia , Neurônios/patologia , Toxoplasmose Animal , Toxoplasmose/patologia , Animais , Cerebelo/citologia , Modelos Animais de Doenças , Camundongos , Neurônios Motores/metabolismo , Neurônios/metabolismo , Toxoplasma , Toxoplasmose/metabolismo
10.
Parasitol Res ; 119(10): 3165-3180, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32789534

RESUMO

Parasitic diseases affect more than one billion people worldwide, and most of them are chronic conditions in which the treatment and prevention are difficult. The appearance of granulomas, defined as organized and compact structures of macrophages and other immune cells, during various parasitic diseases is frequent, since these structures will only form when individual immune cells do not control the invading agent. Th2-typering various parasitic diseases are frequent, since these structures will only form when individual immune cells do not control the invading agent. The characterization of granulomas in different parasitic diseases, as well as recent findings in this field, is discussed in this review, in order to understand the significance of the granuloma and its modulation in the host-parasite interaction and in the immune, pathological, and parasitological aspects of this interaction. The parasitic granulomatous diseases granulomatous amebic encephalitis, toxoplasmosis, leishmaniasis, neurocysticercosis, and schistosomiasis mansoni are discussed as well as the mechanistic and dynamical aspects of the infectious granulomas.


Assuntos
Granuloma/imunologia , Granuloma/patologia , Macrófagos/imunologia , Neurocisticercose/imunologia , Esquistossomose mansoni/imunologia , Toxoplasmose/imunologia , Animais , Granuloma/parasitologia , Interações Hospedeiro-Parasita/imunologia , Humanos , Macrófagos/patologia , Neurocisticercose/patologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/patologia , Taenia solium/imunologia , Toxoplasma/imunologia , Toxoplasmose/patologia
11.
Parasitol Res ; 119(6): 1989-1995, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32291469

RESUMO

Recent advances in chronic toxoplasmosis understanding became the focus of discussion about behavioral abnormalities, which could be explained by cyst location and neuronal impairment in specific brain areas. Perineuronal nets (PNNs) are specialized extracellular matrices that surround the neuronal body and proximal dendrites and play key roles in neuronal circuitry maintenance and stabilization. Its impairment can lead to abnormal synaptic functioning with behavioral repercussions. In this context, we analyzed the impact of Toxoplasma gondii infection on neuronal integrity in the Corpus striatum of chronically infected mice. C57BL/6 and Balb/c female mice were infected with T. gondii ME49 cysts. Brain sections were submitted to immunohistochemistry with Wisteria floribunda agglutinin (WFA) for PNN labeling followed by quantification of tissue cyst and labeled neuronal cells 30 days after infection. Our results revealed that C57BL/6 exhibited a significant decrease in PNN-positive (WFA+) labeled neurons and an expressively higher number of tissue cysts than Balb/c mice. It was also possible to observe that the number of T. gondii tissue cysts and the number of WFA+ neurons were inversely correlated for C57BL/6-infected mice. However, no correlation was observed for Balb/c mice. These data suggest how the impact of parasite dissemination in the brain and host characteristics can influence neuronal integrity impairment during infection by decreasing WFA+ neurons. This might be a plausible pathway in which the presence of T. gondii contributes to behavioral changes in the infected host.


Assuntos
Corpo Estriado/patologia , Neurônios/patologia , Toxoplasmose/patologia , Animais , Doença Crônica , Matriz Extracelular/patologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Lectinas de Plantas , Receptores de N-Acetilglucosamina , Toxoplasma , Toxoplasmose/metabolismo
12.
Parasitol Int ; 76: 102065, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32001348

RESUMO

Trypanosoma cruzi, the causative agent of Chagas disease, and Toxoplasma gondii, which is responsible for Toxoplasmosis, are two parasites that cause significant protozoan zoonoses and consequently important economic losses in human, companion animals and livestock. For the congenital transmission to occur, both parasites must cross the barrier present in the mammalian placenta, which differs between species. Particularly, hemochorial, endotheliochorial and epitheliochorial placental barriers are present, respectively, in human, dog and sheep. The type of placental barrier has been associated with the probability of transmission of pathogens. In this study, we used experimental placental ex vivo infection models of T. cruzi and T. gondii in the above-mentioned mammals in order to study tissue alterations and to compare infection efficiency. Here, we infected placental term explants from human, dog and sheep and analyzed tissue damage by standard histological and histochemical methods. Comparative infection efficiency was determined by quantitative PCR. Both parasites are able to infect the different placental explants; however, more T. gondii parasites were detected, and T. gondii causes a more severe tissue damage in human and canine explants than T. cruzi. The histopathological changes observed in ovine placenta explants were similar in presence of both parasites. We conclude that the infection efficiency of T. gondii is higher, compared to T. cruzi, during the ex vivo infection of human, canine and ovine placental explants. In addition, the ex vivo infection of mammalian placental explants constitutes an interesting experimental approach to study part of the infection mechanisms as well as host responses during congenital infection of both parasites.


Assuntos
Doença de Chagas/patologia , Placenta/patologia , Placenta/parasitologia , Toxoplasmose Animal/patologia , Toxoplasmose/patologia , Animais , Doença de Chagas/veterinária , Cães/parasitologia , Feminino , Humanos , Técnicas In Vitro , Gravidez , Ovinos/parasitologia , Toxoplasma/patogenicidade , Trypanosoma cruzi/patogenicidade
13.
Arch Immunol Ther Exp (Warsz) ; 68(1): 3, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31965304

RESUMO

The effects of infection with Toxoplasma gondii vary from asymptomatic to the development of alterations in various organs (including the liver and kidneys) which may be irreversible, and lead to the death of the host. Whereas homeopathy is an alternative and effective method for treating various diseases, including those caused by protozoa, we questioned the effect of using Lycopodium clavatum in mice infected with T. gondii. One hundred male Swiss mice, 60 days old, were divided into four groups (n = 25/group): NIC (uninfected and untreated control), IC (infected and treated with un-dynamized 7% alcohol solution [vehicle]), G48 (infected and treated 48 h before infection and treated three more times; at 2, 4, and 6 days post-infection (dpi) with L. clavatum 200dH), and G72 (infected and treated for 3 consecutive days before infection with L. clavatum 200dH). In this study, physiological, histopathological, and immunological parameters were evaluated. The L. clavatum 200dH intensified renal damage in mice infected with T. gondii from 7 dpi, causing severe and progressive alterations during this period, such as various degrees of inflammation, edema, atrophy, and tubular cystic dilation, degenerated tubules with intra-cytoplasmic vacuoles and coalescing spots, severe vascular lesions, glomerulonephritis, and peri-glomerular congestion. In the G72 animals, which received L. clavatum 200dH, more severe cortex damage was observed (91.66-96.66%) as compared to the IC group (55-80%) and more renal corpuscle, and renal tubule injury was observed (80 ± 5 to 96.7% ± 2.89 of the total area) during all periods, as compared to the IC group (p < 0.05). Both groups presented high liver enzyme levels, and the highest values for AST were observable at 60 dpi. We observed significant increases of type I and III collagen, as well as high levels of TGF-ß1 in both organs of the treated animals, the main factor involved in fibrosis in areas damaged by the process. L. clavatum 200dH intensifies kidney and liver alterations in mice infected with T. gondii. Our results reinforce caution when indicating administration schemes and dosages for ultra-diluted drugs.


Assuntos
Glomerulonefrite/patologia , Hepatite/patologia , Homeopatia/efeitos adversos , Lycopodium/efeitos adversos , Toxoplasmose/tratamento farmacológico , Animais , Colágeno/metabolismo , Modelos Animais de Doenças , Fibrose , Glomerulonefrite/metabolismo , Glomerulonefrite/parasitologia , Hepatite/metabolismo , Hepatite/parasitologia , Masculino , Camundongos , Preparações de Plantas/efeitos adversos , Toxoplasma/patogenicidade , Toxoplasmose/patologia , Fator de Crescimento Transformador beta1/metabolismo
14.
Mem. Inst. Oswaldo Cruz ; 115: e200007, 2020. graf
Artigo em Inglês | LILACS, Sec. Est. Saúde SP | ID: biblio-1135242

RESUMO

BACKGROUND Behavioral and neurochemical alterations associated with toxoplasmosis may be influenced by the persistence of tissue cysts and activation of an immune response in the brain of Toxoplasma gondii-infected hosts. The cerebral extracellular matrix is organised as perineuronal nets (PNNs) that are both released and ensheath by some neurons and glial cells. There is evidences to suggest that PNNs impairment is a pathophysiological mechanism associated with neuropsychiatric conditions. However, there is a lack of information regarding the impact of parasitic infections on the PNNs integrity and how this could affect the host's behavior. OBJECTIVES In this context, we aimed to analyse the impact of T. gondii infection on cyst burden, PNNs integrity, and possible effects in the locomotor activity of chronically infected mice. METHODS We infected mice with T. gondii ME-49 strain. After thirty days, we assessed locomotor performance of animals using the open field test, followed by evaluation of cysts burden and PNNs integrity in four brain regions (primary and secondary motor cortices, prefrontal and somesthetic cortex) to assess the PNNs integrity using Wisteria floribunda agglutinin (WFA) labeling by immunohistochemical analyses. FINDINGS AND MAIN CONCLUSIONS Our findings revealed a random distribution of cysts in the brain, the disruption of PNNs surrounding neurons in four areas of the cerebral cortex and hyperlocomotor behavior in T. gondii-infected mice. These results can contribute to elucidate the link toxoplasmosis with the establishment of neuroinflammatory response in neuropsychiatric disorders and to raise a discussion about the mechanisms related to changes in brain connectivity, with possible behavioral repercussions during chronic T. gondii infection.


Assuntos
Animais , Camundongos , Cerebelo/metabolismo , Toxoplasmose/patologia , Toxoplasmose Animal , Matriz Extracelular/metabolismo , Neurônios Motores/citologia , Neurônios/patologia , Toxoplasma , Cerebelo/citologia , Toxoplasmose/metabolismo , Modelos Animais de Doenças , Neurônios Motores/metabolismo , Neurônios/metabolismo
15.
Parasitol Res ; 118(6): 1899-1918, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30949853

RESUMO

After host cell invasion, Toxoplasma secretes a variety of dense granule proteins (GRA proteins) from its secretory dense granules, which are involved in the biogenesis of the parasitophorous vacuole (PV). TgGRA8I is predicted to contain proline-rich domains, which are structural features of some cytoskeleton-related proteins. In agreement with this observation, previous proteomic analyses revealed the presence of TgGRA8I in the Toxoplasma sub-pellicular cytoskeleton. In the present study, we show (1) by docking analyses that TgGRA8I may interact with both Toxoplasma ß-tubulin and actin; (2) by immunoelectron microscopy, proteomic, biochemical, and cellular approaches that TgGRA8I associates with sub-pellicular microtubules and actin at the parasite sub-pellicular cytoskeleton; (3) that type I parasites (RH strain) lacking the GRA8 gene (RHΔku80Δgra8) exhibit loss of conoid extrusion, diminished cell infection, and egress capabilities, and that these motility impairments were likely due to important alterations in their sub-pellicular cytoskeleton, in particular their sub-pellicular microtubules and meshwork. Parasites lacking the GRA4 gene (RHΔku80Δgra4) did not show modifications in the organization of the sub-pellicular cytoskeleton. Collectively, these results demonstrated that TgGRA8I is a dense granule protein that, besides its role in the formation of the PV, contributes to the organization of the parasite sub-pellicular cytoskeleton and motility. This is the first proline-rich protein described in the Toxoplasma cytoskeleton, which is a key organelle for both the parasite motility and the invasion process. Knowledge about the function of cytoskeleton components in Toxoplasma is fundamental to understand the motility process and the host cell invasion mechanism. Refining this knowledge should lead to the design of novel pharmacological strategies for the treatment against toxoplasmosis.


Assuntos
Actinas/metabolismo , Antígenos de Protozoários/metabolismo , Movimento Celular/genética , Citoesqueleto/metabolismo , Proteínas de Protozoários/metabolismo , Toxoplasma/metabolismo , Toxoplasma/patogenicidade , Tubulina (Proteína)/metabolismo , Animais , Antígenos de Protozoários/genética , Transporte Biológico , Microscopia Imunoeletrônica , Microtúbulos/metabolismo , Simulação de Acoplamento Molecular , Proteômica , Proteínas de Protozoários/genética , Vesículas Secretórias/metabolismo , Toxoplasma/genética , Toxoplasmose/parasitologia , Toxoplasmose/patologia , Vacúolos/parasitologia
16.
PLoS One ; 14(2): e0212375, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30763391

RESUMO

Human toxoplasmosis, a protozoonosis caused by Toxoplasma gondii, has been described as a worldwide foodborne disease with important public health impact. Despite infection has reportedly varied due to differences in alimentary, cultural and hygienic habits and geographic region, social vulnerability influence on toxoplasmosis distribution remains to be fully established. Accordingly, the present study has aimed to assess T. gondii seroprevalence and factors associated to social vulnerability for infection in households of Ivaiporã, southern Brazil, with 33.6% population making half minimum wage or less, ranked 1,055th in population (31,816 habitants), 1,406th in per capita income (U$ 211.80 per month) and 1,021st in HDI (0.764) out of 5,570 Brazilian cities. Serum samples and epidemiological questionnaires were obtained from citizen volunteers with official City Secretary of Health assistance in 2015 and 2016. In overall, serosurvey has revealed 526/715 (73.57%) positive samples for anti-T. gondii antibodies by Indirect Fluorescent Antibody Test. Logistic regression has shown a significant increase associated to adults (p = 0.021) and elderly (p = 0.014) people, illiterates (p = 0.025), unemployment (p <0.001) and lack of household water tank (p = 0.039). On the other hand, sex (male or female), living area (urban or rural), yard hygiene, meat ingestion, sand or land contact, owning pets (dog, cat or both) were not significant variables of positivity for anti-T. gondii antibodies in the surveyed population. Although no significant spatial cluster was found, high intensity areas of seropositive individuals were located in the Kernel map where the suburban neighborhoods are located. In conclusion, socioeconomic vulnerability determinants may be associated to Toxoplasma gondii exposure. The increased risk due to illiteracy, adult or elderly age, unemployment and lack of household water tank were confirmed by multivariate analysis and the influence of low family income for seropositivity by the spatial analysis.


Assuntos
Toxoplasma/isolamento & purificação , Toxoplasmose/patologia , Adolescente , Adulto , Fatores Etários , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Toxoplasma/imunologia , Toxoplasma/fisiologia , Toxoplasmose/economia , Toxoplasmose/epidemiologia , Desemprego , Adulto Jovem
17.
Pathog Dis ; 77(9)2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32068829

RESUMO

In this study, we evaluated homeostatic and functional disorders of the spleen in mice inoculated with Toxoplasma gondii. The kinetics of megakaryocyte and leukocyte production, body and spleen mass and certain histopathological aspects were analyzed. There was increased (P < 0.05) the accumulation of lipofuscin in the red pulp of the spleen, in the periods of 30 and 60 dpi of the infection, that is, in the chronification stage of the disease and decrease of the white pulp area. In addition, we observed (from 7dpi) a quantitative and qualitative increase (P < 0.05) in the deposition of collagen fibers in the spleen of all infected mice. Since resolution of the inflammatory process resulted in pathophysiological changes, we can suggest that the T. gondii invaded and multiplied in the cells of the white and red pulps of the spleen. Although we did not find the parasite in the spleen, this hypothesis is supported by the presence of diffuse inflammatory infiltrate, which extended through the spleen parenchyma of all inoculated mice. Taken together, our results suggest that T. gondii causes severe homeostatic disorders that have altered spleen physiology, including diffuse parenchymal inflammation, lipofuscinosis in histiocytes, early aging, collagenopathy, systemic sclerosis and spleen and white pulp atrophy.


Assuntos
Colágeno/metabolismo , Lipofuscina/metabolismo , Baço/patologia , Toxoplasma , Toxoplasmose/patologia , Animais , Atrofia , Inflamação , Camundongos , Baço/metabolismo , Toxoplasmose/metabolismo
18.
Neurogastroenterol Motil ; 31(3): e13523, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30537037

RESUMO

BACKGROUND: Toxoplasma gondii infection can occur through the ingestion of raw meat that contains tissue cysts or food that contains oocysts. Through the ingestion of oocysts, the parasite crosses the intestinal barrier, where the enteric nervous system is located. The objective was to investigate the kinetics of neuronal and glial responses during acute T. gondii infection. METHODS: We used 45 Wistar rats that were divided into a control group and infected groups that were evaluated at 6, 12, 24, 48, 72 hours, 7 days, 10 days, and 15 days after infection. The rats received 5000 sporulated oocysts of the parasite orally. To detect neurons and enteric glia cells, the myenteric and submucosal plexuses of the duodenum underwent double-labeling immunohistochemical techniques to evaluate HuC/HuD and S100, HuC/HuD and ChAT, and HuC/HuD and nNOS. KEY RESULTS: We observed a reduction of the total neuron population in the submucosal plexus 72 hours after infection. Cholinergic neurons decreased in the submucosal plexus 15 days after infection, and nitrergic neurons decreased in the myenteric plexus 72 hours after infection. A decrease in the number of glial cells was observed 7 days after infection in the submucosal plexus, and an increase in the enteric glial cell (EGC)/neuron ratio was found in both plexuses 48 hours after infection. CONCLUSIONS AND INFERENCES: We found decrease of neurons and increase in the EGC/neuron ratio in both plexuses caused by acute T. gondii infection, with major alterations 72 hours after oral infection. The number of cholinergic neurons decreased in the submucosal plexus, and the number of nitrergic neurons decreased in the myenteric plexus. A decrease in the number of enteric glial cells was observed in the submucosal plexus, and an increase in the enteric glial cell/neuron ratio was observed in both ganglionate plexuses of the duodenum.


Assuntos
Duodeno/patologia , Neuroglia/patologia , Neurônios/patologia , Toxoplasmose/patologia , Doença Aguda , Animais , Contagem de Células , Imuno-Histoquímica , Plexo Mientérico/patologia , Sistema Nervoso Parassimpático/patologia , Ratos , Ratos Wistar , Plexo Submucoso/patologia
19.
Microb Pathog ; 123: 153-161, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30003946

RESUMO

This study was conducted to investigate annexin A1 (ANXA1) functions in human placental explants infected with Toxoplasma gondii (T. gondii). We examined the first and third trimester placental explants infected with T. gondii (n = 7 placentas/group) to identify the number and location of parasites, ANXA1 protein, potential involvement of formyl peptide receptors (FPR1 and FPR2), and COX-2 expressions by immunohistochemistry. Treatments with Ac2-26 mimetic peptide of ANXA1 were performed to verify the parasitism rate (ß-galactosidase assay), prostaglandin E2 levels (ELISA assay), and ANXA1, FPR1 and COX-2 expression in third trimester placentas. Placental explants of third trimester expressed less ANXA1 and were more permissive to T. gondii infection than first trimester placentas that expressed more ANXA1. Ac2-26 treatment increases endogenous ANXA1 and decreases parasitism rate, COX-2, and prostaglandin E2 levels. Altogether, these data provide further insight into the anti-parasitic and anti-inflammatory effects of ANXA1 in placentas infected with T. gondii.


Assuntos
Anexina A1/farmacologia , Antiparasitários/farmacologia , Placenta/efeitos dos fármacos , Toxoplasma/efeitos dos fármacos , Toxoplasma/patogenicidade , Toxoplasmose/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Estudos Transversais , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Feminino , Humanos , Inflamação/tratamento farmacológico , Peptídeos/farmacologia , Placenta/patologia , Placenta/fisiopatologia , Gravidez , Terceiro Trimestre da Gravidez , Receptores de Formil Peptídeo/metabolismo , Receptores de Lipoxinas/metabolismo , Toxoplasmose/patologia , beta-Galactosidase/análise
20.
Autops. Case Rep ; 8(1): e2018012, Jan.-Mar. 2018. ilus
Artigo em Inglês | LILACS | ID: biblio-905427

RESUMO

Extracerebral toxoplasmosis, with pulmonary involvement and shock, is a rare form of toxoplasmosis in patients with advanced AIDS. It can mimic pneumocystosis, histoplasmosis, and disseminated tuberculosis, and should be considered in the differential diagnosis of causes of respiratory failure and fulminant disease in this group of individuals, especially in areas where the Toxoplasma gondii infection is highly prevalent and in those without proper use of antimicrobial prophylaxis. We report the case of a 46-year-old male patient who presented to the emergency department with uremia, requiring urgent dialysis. During the laboratorial investigation, the patient had confirmed HIV infection, with a low CD4+ peripheral T-cell count (74 cells/µL). During hospitalization, the patient presented drug-induced hepatitis due to trimethoprim/sulfamethoxazole in a prophylactic dose, requiring interruption of this medication. On the 55th day of hospitalization, the patient developed refractory shock and died. At the autopsy, disseminated toxoplasmosis with encephalitis and severe necrotizing pneumonia were diagnosed, with numerous tachyzoites in the areas of pulmonary necrosis.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas Relacionadas com a AIDS/complicações , Encefalite Infecciosa/complicações , Pneumonia/complicações , Choque/complicações , Toxoplasmose Cerebral/complicações , Autopsia , Diagnóstico Diferencial , Evolução Fatal , Toxoplasma , Toxoplasmose/patologia
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