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1.
Front Cell Infect Microbiol ; 14: 1412345, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38988814

RESUMEN

P21 is a protein secreted by all forms of Trypanosoma cruzi (T. cruzi) with recognized biological activities determined in studies using the recombinant form of the protein. In our recent study, we found that the ablation of P21 gene decreased Y strain axenic epimastigotes multiplication and increased intracellular replication of amastigotes in HeLa cells infected with metacyclic trypomastigotes. In the present study, we investigated the effect of P21 in vitro using C2C12 cell lines infected with tissue culture-derived trypomastigotes (TCT) of wild-type and P21 knockout (TcP21-/-) Y strain, and in vivo using an experimental model of T. cruzi infection in BALB/c mice. Our in-vitro results showed a significant decrease in the host cell invasion rate by TcP21-/- parasites as measured by Giemsa staining and cell count in bright light microscope. Quantitative polymerase chain reaction (qPCR) analysis showed that TcP21-/- parasites multiplied intracellularly to a higher extent than the scrambled parasites at 72h post-infection. In addition, we observed a higher egress of TcP21-/- trypomastigotes from C2C12 cells at 144h and 168h post-infection. Mice infected with Y strain TcP21-/- trypomastigotes displayed higher systemic parasitemia, heart tissue parasite burden, and several histopathological alterations in heart tissues compared to control animals infected with scrambled parasites. Therewith, we propose that P21 is important in the host-pathogen interaction during invasion, cell multiplication, and egress, and may be part of the mechanism that controls parasitism and promotes chronic infection without patent systemic parasitemia.


Asunto(s)
Enfermedad de Chagas , Proteínas Protozoarias , Trypanosoma cruzi , Animales , Humanos , Ratones , Línea Celular , Enfermedad de Chagas/parasitología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Modelos Animales de Enfermedad , Técnicas de Inactivación de Genes , Interacciones Huésped-Parásitos , Ratones Endogámicos BALB C , Parasitemia , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Trypanosoma cruzi/genética , Trypanosoma cruzi/patogenicidad , Trypanosoma cruzi/fisiología , Trypanosoma cruzi/metabolismo , Virulencia
2.
Toxicon ; 243: 107742, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38705486

RESUMEN

Phospholipases A2 (PLA2s) from snake venom possess antitumor and antiangiogenic properties. In this study, we evaluated the antimetastatic and antiangiogenic effects of MjTX-II, a Lys49 PLA2 isolated from Bothrops moojeni venom, on lung cancer and endothelial cells. Using in vitro and ex vivo approaches, we demonstrated that MjTX-II reduced cell proliferation and inhibited fundamental processes for lung cancer cells (A549) growth and metastasis, such as adhesion, migration, invasion, and actin cytoskeleton decrease, without significantly interfering with non-tumorigenic lung cells (BEAS-2B). Furthermore, MjTX-II caused cell cycle alterations, increased reactive oxygen species production, modulated the expression of pro- and antiangiogenic genes, and decreased vascular endothelial growth factor (VEGF) expression in HUVECs. Finally, MjTX-II inhibited ex vivo angiogenesis processes in an aortic ring model. Therefore, we conclude that MjTX-II exhibits antimetastatic and antiangiogenic effects in vitro and ex vivo and represents a molecule that hold promise as a pharmacological model for antitumor therapy.


Asunto(s)
Inhibidores de la Angiogénesis , Bothrops , Proliferación Celular , Venenos de Crotálidos , Neoplasias Pulmonares , Animales , Humanos , Inhibidores de la Angiogénesis/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Fosfolipasas A2/farmacología , Movimiento Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Células A549 , Línea Celular Tumoral , Antineoplásicos/farmacología , Neovascularización Patológica/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Serpientes Venenosas
3.
Cancer Epidemiol ; 91: 102593, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38815484

RESUMEN

INTRODUCTION: Acute myeloid leukemia patients are at high risk for infections, which contribute to increased mortality rates of up to 70%. The use of antimicrobial prophylaxis has been shown to significantly lower rates of infection. Therefore, this retrospective study aimed to evaluate the effect of two agents that showed effective results in the literature, levofloxacin and fluconazole, as prophylaxis strategies in AML patients. METHODOLOGY: A total of 85 AML patients' medical records treated with a 7+3 induction chemotherapy protocol in the Cancer Hospital of Uberlândia from 2017 to 2021 were screened and their data was collected. Within these patients, groups for analysis were created based on whether the acting physician included an antibacterial or antifungal prophylaxis protocol during induction. Contingency tables with χ² and odds ratio tests were realized to verify associations between prophylaxis and infection. Additionally, Kaplan-Meier curves with Cox regression were developed to analyze survival. RESULTS: The use of prophylaxis with either fluconazole or levofloxacin did not lower rates of infection, as those who with prophylaxis did not demonstrate significant differences when compared to those without (20.3-29.7%, and 12.3-23.3%, respectively). Patients who suffered a bacterial infection during induction were shown to have lower overall survival, with a similar trend seen in fungal infections. CONCLUSION: Bacterial and fungal infections were associated with higher rates of induction mortality and lower overall survival, and prophylaxis using fluconazole and levofloxacin did not present any significant difference in preventing these infections in this study, contrasting results found in the literature. The individuality of each treatment center should be taken into consideration and future studies should be realized to better determine the most effective methods and agents for prophylaxis.


Asunto(s)
Antifúngicos , Fluconazol , Leucemia Mieloide Aguda , Levofloxacino , Humanos , Fluconazol/administración & dosificación , Fluconazol/uso terapéutico , Levofloxacino/uso terapéutico , Levofloxacino/administración & dosificación , Leucemia Mieloide Aguda/tratamiento farmacológico , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Antifúngicos/uso terapéutico , Antifúngicos/administración & dosificación , Adulto , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Profilaxis Antibiótica/métodos , Infecciones Bacterianas/prevención & control , Infecciones Bacterianas/epidemiología , Micosis/prevención & control , Micosis/epidemiología , Quimioterapia de Inducción/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Adulto Joven
4.
Biochem Biophys Res Commun ; 706: 149748, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38460450

RESUMEN

Angiogenesis is a process that is controlled by a delicate combination of proangiogenic and antiangiogenic molecules and can be disrupted in various illnesses, including cancer. Non-cancerous diseases can also have an abnormal or insufficient vascular growth, inflammation and hypoxia, which exacerbate angiogenesis. These conditions include atherosclerosis, psoriasis, endometriosis, asthma, obesity and AIDS. Based on that, the present work assessed the in vitro and ex vivo antiangiogenic properties stemming from BthMP, a P-I metalloproteinase from Bothrops moojeni snake venom, via the VEGF pathway. BthMP at a concentration of 5 and 40 µg/mL showed no toxicity to endothelial cells (HUVEC) in the MTT assay and was not able to induce necrosis and colony proliferation. Interestingly, BthMP inhibited adhesion, migration and invasion of HUVECs in Matrigel and arrested in vitro angiogenesis by reducing the average number of nodules in toxin-treated cells by 9.6 and 17.32 at 5 and 40 µg/mL, respectively, and the number of tubules by 15.9 at 5 µg/mL and 21.6 at 40 µg/mL in a VEGF-dependent way, an essential proangiogenic property. Furthermore, BthMP inhibited the occurrence of the angiogenic process in an ex vivo aortic ring test by decreasing new vessel formation by 52% at 5 µg/mL and by 66% at 40 µg/mL and by increasing the expression of an antiangiogenic gene, SFLT-1, and decreasing the expression of the proangiogenic genes VEGFA and ANGPT-1. Finally, this toxin reduces the production of nitric oxide, a marker that promotes angiogenesis and VEGF modulation, and decreases the protein expression of VEGFA in the supernatant of the HUVEC culture by about 30 %. These results suggest that BthMP has a promising antiangiogenic property and proves to be a biotechnological mechanism for understanding the antiangiogenic responses induced by snake venom metalloproteinases, which could be applied to a variety of diseases that exhibit an imbalance of angiogenesis mechanisms.


Asunto(s)
Bothrops , Células Endoteliales , Serpientes Venenosas , Animales , Femenino , Humanos , Células Endoteliales/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Bothrops/metabolismo , Metaloproteasas/metabolismo , Venenos de Serpiente , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Inhibidores de la Angiogénesis/farmacología
5.
Cancer Treat Res Commun ; 38: 100790, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38241969

RESUMEN

PURPOSE: Hodgkin's lymphoma is currently treated with a chemotherapy protocol consisting of doxorubicin, bleomycin, vinblastine, and dacarbazine. Due to Brazil facing a bleomycin shortage in 2017, and this drug's high toxicity, this retrospective study evaluates the effect that the absence of bleomycin had on treatment response and overall survival of Hodgkin's lymphoma patients. METHODS: The medical records of 126 HL patients treated between 2007 and 2021 were reviewed and their data collected, followed by grouping into ABVD and AVD groups according to bleomycin use. Data concerning the patient's characteristics, cancer type, and treatment plan were analyzed with proportion tests, Kaplan-Meier curves. univariate Cox regression, and χ2 tests. RESULTS: No discernible differences were found in this study between the overall survival and recurrence rate of patients treated with bleomycin compared to those without. Additionally, there was an increased risk of death in each subsequent cycle of chemotherapy of the complete ABVD protocol, demonstrating a risk of toxicity. Among the variables analyzed, hypertension and the presence of B symptoms were also associated with an increased risk of death, while the use of radiotherapy significantly improved survival. CONCLUSION: The results of this study suggest that bleomycin did not impact the outcome of Hodgkin's lymphoma treatment. Moreover, the increased risk of death associated with its toxicity during each cycle of treatment raises concerns about its role as an essential component of the gold standard for Hodgkin's lymphoma treatment. Therefore, further research and consideration are needed to reassess the use of bleomycin in Hodgkin's lymphoma treatment protocols.


Asunto(s)
Enfermedad de Hodgkin , Humanos , Enfermedad de Hodgkin/patología , Bleomicina/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Estudios Retrospectivos , Doxorrubicina/efectos adversos , Vinblastina/efectos adversos , Dacarbazina/efectos adversos
6.
Braz. oral res. (Online) ; 36: e065, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS, BBO | ID: biblio-1374743

RESUMEN

Abstract: Solubility, pH, ion release, cytotoxicity, and osteoclastogenesis inhibition in bone marrow-derived monocyte macrophages (BMMs) were evaluated in EndoSequence BC Sealer (END), Bio-C Sealer (BC), and Sealer Plus BC (SPBC). pH was determined after immersion of the sealers in deionized water (DW) and Minimum Essential Medium Alpha (α-MEM). Solubility was obtained by mass loss. Ion release was measured by using X-ray fluorescence spectroscopy (XRF). Cytotoxicity was evaluated by MTT assay. Inhibition of osteoclastogenesis was evaluated by tartrate-resistant acid phosphatase (TRAP). Data were analyzed using the t-test, ANOVA and Tukey/Dunnett's post-hoc tests (α = 0.05). END had the highest pH in DW (p < 0.05), and BC, in α-MEM (p < 0.05). Solubility in DW was the lowest for SPBC (p < 0.005). The highest calcium release was observed for BC in DW at 12 h (p < 0.05), and in α-MEM at 12 and 24 h (p < 0.05). The lowest toxicity was detected for END (p < 0.05). BC had the highest inhibitory effect on osteoclasts (p < 0.05). Overall, the highest solubility and pH values were found in DW. However, the calcium silicate-based sealer showed higher solubility than the ISO standards. Calcium release was the highest for BC. END showed the highest cell viability, and BC, the highest osteoclast inhibition.

7.
Biosci. j. (Online) ; 36(6): 2203-2210, 01-11-2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1148290

RESUMEN

Sensitization with conceptus antigens has been shown to be useful for improving reproductive performance facilitating maternal acceptance of an allogeneic embryo through the induction of cytokines and immunoregulatory cells in the uterine microenvironment. As FOXP3, IDO, IL10 and CSF1 in the uterus are important on the recognition and development of embryos during early pregnancy, this study aimed to determine whether simultaneous or isolated administration of paternal (semen) and maternal (PBMCs) antigens in the uterus of cow, on the day of estrus, influence the gene expression of these cytokines. Forty crossbred cows were divided into four treatments: T0: Control; T1: Semen; T2: PBMCs (peripheral blood mononuclear cells) from another cow and T3: PBMCs+Semen. Antigens were administered into the uterine body on the estrus day (D0). Uterine biopsies designed for molecular analysis of gene expression were collected in vivo seven (D7) and fourteen (D14) days after immunostimulation. Transcripts from FOXP3, IDO, IL-10 and CSF-1 were detected in all RNA samples extracted from uterine biopsies. The semiquantitative analysis showed that none of the treatments caused significant increase in the expression of these genes. Furthermore, on D14 all treatments led to a decline in the number of CSF-1 transcripts; moreover, treatment with PBMCs+Semen also led to a drop in the abundance of IL-10 transcripts. Such results suggest that isolated or simultaneous administration of both antigens would not increase maternal tolerance to embryo alloantigens, nor would it create favorable conditions to its growth and pre-implantation development, at least regarding the effects mediated by these genes on D7 and D14 of the estrous cycle.


A sensibilização intrauterina com antígenos do concepto tem-se mostrado útil para melhorar o desempenho reprodutivo, facilitando a aceitação materna de um embrião alogênico por meio da indução de citocinas e células imunorreguladoras no microambiente uterino. Como FOXP3, IDO, IL10 e CSF1 no útero são importantes no reconhecimento e desenvolvimento de embriões durante a gestação inicial, este estudo teve como objetivo determinar se a administração simultânea ou isolada de antígenos paterno (sêmen) e materno (PBMCs) no útero de vacas, no dia do estro, influenciam a expressão gênica dessas citocinas. Quarenta vacas mestiças foram divididas em quatro tratamentos: T0: Controle; T1: Sêmen; T2: PBMCs (células mononucleares do sangue periférico) e T3: PBMCs + Sêmen. Os antígenos foram administrados no corpo do útero no dia do estro (D0). Biópsias uterinas projetadas para análise molecular da expressão gênica foram coletadas in vivo sete (D7) e catorze (D14) dias após imunoestimulação. Transcritos de FOXP3, IDO, IL-10 e CSF-1 foram detetados em todas as amostras de RNA extraídas de biópsias uterinas. A análise semiquantitativa mostrou que nenhum dos tratamentos causou um aumento significativo na expressão desses genes. Além disso, no D14, todos os tratamentos levaram a um declínio na quantidade de transcritos do CSF-1; Além disso, o tratamento com PBMCs + sêmen também levou a uma queda na abundância de transcritos de IL-10. Estes resultados sugerem que a administração isolada ou simultânea de ambos os antígenos não deve aumentar a tolerância materna aos aloantígenos do embrião, nem deve criar condições favoráveis ao seu crescimento e desenvolvimento pré-implantação, pelo menos em relação aos efeitos mediados por esses genes nos dia sete e catorze do ciclo estral.


Asunto(s)
Bovinos
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