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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.
Mediators Inflamm ; 2019: 5195134, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467484

RESUMO

It has been described that the metalloprotease BmooMP-alpha-I purified from Bothrops moojeni snake venom is able to hydrolyze the TNF molecule. However, this observation has been based mainly on in vitro investigation, in addition to molecular modeling and docking approaches. Considering that there is no in vivo study to demonstrate the biological effects of this enzyme, the major aim to the present work was to investigate whether the BmooMP-alpha-I has any anti-inflammatory efficacy by setting up a murine experimental design of colitis induced by dextran sulfate sodium (DSS). For this purpose, C57BL/6 mice were divided into six groups, as follows: (i) animals without intestinal inflammation, (ii) animals without intestinal inflammation treated with BmooMP-alpha-I (50 µg/animal/day), and (iii) animals with intestinal inflammation induced by 3% of DSS, (iv) mice with intestinal inflammation induced by DSS and treated with BmooMP-alpha-I enzyme at the 50, 25, or 12.5 µg/animal/day dosages by intraperitoneal route. Clinical signs of colitis were observed daily for calculating the morbidity scores, cytokine measurements, and histological features. We observed that the animals treated with different doses of the enzyme presented a remarkable improvement of colitis signs, as confirmed by a significant increase of the intestine length in comparison to the DSS group. Also, no difference was observed between the groups treated with the enzyme or vehicle, as the colon length of these animals was slightly lower than that of the group of healthy animals, without induction of intestinal inflammation. The cytokine quantification in supernatants of intestinal tissue homogenates showed a significant reduction of 38% in IFN-gamma levels, when the animals were treated with 50 µg of the BmooMP-alpha-I compared to the animals receiving DSS only. A significant reduction of 39% in TNF levels was also observed in all doses of treatment with BmooMP-alpha-I, in addition to a significant reduction of 35% in the amount of IL-12p40. Histological examinations revealed that the BmooMP-alpha-I 50 µg treated group preserved colon architecture and goblet cells and reduced the ulcer area, when compared with DSS mice, which showed typical inflammatory changes in tissue architecture, such as ulceration, crypt dilation, loss of tissue architecture, and goblet cell depletion, accompanied by a significant cell infiltration. In conclusion, our results suggest that the improvement of clinical scores and histological findings related to BmooMP-alpha-I treatment in this experimental model could be attributed to the metalloprotease ability to modulate cytokine production locally at the inflamed intestine. These findings highlight the potential anti-inflammatory role and effectiveness of this enzyme as a therapeutic alternative in this type of immunopathological condition.


Assuntos
Colite/induzido quimicamente , Colite/tratamento farmacológico , Sulfato de Dextrana/toxicidade , Metaloendopeptidases/uso terapêutico , Animais , Bothrops , Colite/metabolismo , Citocinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
3.
Toxins (Basel) ; 8(7)2016 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-27447669

RESUMO

Tumor necrosis factor (TNF) is a major cytokine in inflammatory processes and its deregulation plays a pivotal role in several diseases. Here, we report that a zinc metalloprotease extracted from Bothrops moojeni venom (BmooMP-alpha-I) inhibits TNF directly by promoting its degradation. This inhibition was demonstrated by both in vitro and in vivo assays, using known TLR ligands. These findings are supported by molecular docking results, which reveal interaction between BmooMP-alpha-I and TNF. The major cluster of interaction between BmooMP-alpha-I and TNF was confirmed by the structural alignment presenting Ligand Root Mean Square Deviation LRMS = 1.05 Å and Interactive Root Mean Square Deviation IRMS = 1.01 Å, this result being compatible with an accurate complex. Additionally, we demonstrated that the effect of this metalloprotease on TNF is independent of cell cytotoxicity and it does not affect other TLR-triggered cytokines, such as IL-12. Together, these results indicate that this zinc metalloprotease is a potential tool to be further investigated for the treatment of inflammatory disorders involving TNF deregulation.


Assuntos
Bothrops , Venenos de Crotalídeos/metabolismo , Metaloendopeptidases/metabolismo , Simulação de Acoplamento Molecular , Proteínas de Répteis/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Zinco/metabolismo , Animais , Células Cultivadas , Venenos de Crotalídeos/química , Venenos de Crotalídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Metaloendopeptidases/química , Metaloendopeptidases/farmacologia , Camundongos Endogâmicos C57BL , Ligação Proteica , Conformação Proteica , Proteólise , Proteínas de Répteis/química , Proteínas de Répteis/farmacologia , Relação Estrutura-Atividade , Especificidade por Substrato , Receptores Toll-Like/agonistas , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/química , Zinco/química
4.
Toxins (Basel) ; 7(12): 5114-28, 2015 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-26633501

RESUMO

Hymenoptera venoms constitute an interesting source of natural toxins that may lead to the development of novel therapeutic agents. The present study investigated the enzymatic and biological characteristics of the crude venom of the ant Odontomachus bauri. Its crude venom presents several protein bands, with higher staining for six proteins with gelatinolytic activity (17, 20, 26, 29, 43 and 48 kDa). The crude venom showed high proteolytic activity on azocasein at optimal pH 8.0 and 37 °C. In the presence of protease inhibitors as aprotinin, leupeptin and EDTA, the azocaseinolytic activity was reduced by 45%, 29% and 9%, respectively, suggesting that the enzymes present in the crude venom belong to the three classes of proteases, with the serine proteases in greater intensity. The crude venom degraded the fibrinogen α-chain faster than the ß-chain, while the fibrinogen γ-chain remained unchanged. In biological assays, O. bauri venom showed hemolytic and coagulant activity in vitro, and defibrinating activity in vivo. In addition, the venom showed antimicrobial activity against Staphylococcus aureus and Escherichia coli as well as antiparasitic activity on Toxoplasma gondii infection in vitro. In that sense, this study sheds perspectives for pharmacological applications of O. bauri venom enzymes.


Assuntos
Venenos de Formiga , Proteínas de Insetos , Peptídeo Hidrolases , Animais , Venenos de Formiga/enzimologia , Venenos de Formiga/toxicidade , Antibacterianos/toxicidade , Antiparasitários/toxicidade , Formigas , Sobrevivência Celular/efeitos dos fármacos , Coagulantes/toxicidade , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Células HeLa , Hemólise , Humanos , Proteínas de Insetos/metabolismo , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Peptídeo Hidrolases/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Toxoplasma/efeitos dos fármacos , Toxoplasma/patogenicidade
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