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1.
Acta cir. bras ; 36(4): e360401, 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1248545

RESUMO

ABSTRACT Purpose Quantify the tissue content of metalloproteinase-9 (MMP-9) and collagen in colic mucosa with and without intestinal transit after infliximab administration in rats subjected to Hartmann's surgery. Methods Twenty-two rats underwent colon diversion by Hartmann's surgery. Animals were maintained with intestinal bypass for 12 weeks to induce development of diversion colitis (DC). Afterwards, animals were divided into three groups: first group received subcutaneous application of saline solution (SS) 0.9%, while the remaining two groups received infliximab subcutaneously at doses of 5 or 10 mg·kg-1·week-1 for five consecutive weeks. After the intervention, animals were sacrificed, removing the segments with and without intestinal transit. Diversion colitis was diagnosed by histological study, and its intensity was determined by a validated inflammatory scale. Tissue expression of MMP-9 was assessed byimmunohistochemistry, while total collagen was assessed by histochemistry. Tissue content of both was measuredby computerized morphometry. Results Colon segments without intestinal transit had a higher degree of inflammation, which improved in animals treated with infliximab. Collagen content was always lower in those without intestinal transit. There was an increase in the collagen content in the colon without transit in animals treated with infliximab, primarily at a dose of 10 mg·kg-1·week-1. There was an increase in the content of MMP-9 in the colon without fecal transit, and a reduction was observed in animals treated with infliximab, regardless of the dose used. Conclusions Application of infliximab reduces inflammation, increases the total collagen content and decreases the content of MMP-9 in the colon without intestinal transit.


Assuntos
Animais , Ratos , Colo/cirurgia , Mucosa Intestinal , Colágeno , Ratos Wistar , Metaloproteases , Infliximab
2.
Clinics ; 76: e2145, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153958

RESUMO

OBJECTIVES: Arterial embolization of myomas (AEM) is controversial because of the changes that occur in the extracellular matrix (ECM) of the endometrium and its effect on gestational success in infertile patients desiring reproductive capability. Therefore, we performed this study on the expression of genes in the ECM of the endometrium, such as those coding metalloproteinases (MMP), before and 6 months after embolization of the uterine arteries. METHODS: Seven women with leiomyomas were evaluated, and MMP3 and MMP10 levels were measured. The women underwent pelvic nuclear magnetic resonance (NMR), examination, and endometrial biopsy between the 20th and 24th day of the menstrual cycle, and pre- and post-AEM (after 6 months). For data analysis, the Cq comparative method, also known as the 2-ΔΔCT method, was used to calculate the relative quantities of MMP gene expression among the samples collected. RESULTS: There was a significant decrease by 9.52 times in the expression of MMP3 (p=0.007), and a non-significant change in the expression of MMP10 (p=0.22) in post-AEM-treated women than pre-AEM-treated women. CONCLUSIONS: The results suggest that ECM continues to undergo tissue remodeling 6 months after AEM, at least with regard to MMP3 expression, suggesting that AEM affects the ECM for at least 6 months after the procedure.


Assuntos
Humanos , Feminino , Endométrio , Mioma , Metaloproteases , Matriz Extracelular , Artéria Uterina
3.
J. venom. anim. toxins incl. trop. dis ; 27: e20200180, 2021. tab, graf
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1287094

RESUMO

Snake venoms are composed of pharmacologically active proteins that are evolutionarily diverse, stable and specific to targets. Hence, venoms have been explored as a source of bioactive molecules in treating numerous diseases. Recent evidences suggest that snake venom proteins may affect the formation of new blood vessels. Excessive angiogenesis has been implicated in several pathologies including tumours, diabetic retinopathy, arthritis, inter alia. In the present study, we have examined the effects of P-I metalloproteinases isolated from Bothrops moojeni (BmMP-1) and Bothrops atrox (BaMP-1) and L-amino acid oxidases (LAAO) isolated from B. moojeni (BmLAAO) and B. atrox (BaLAAO) on biochemical and functional aspects of angiogenesis. Methods: P-I metalloproteinases and LAAO were purified from venom by molecular size exclusion and ion-exchange chromatography and subsequently confirmed using mass spectrometry. The P-I metalloproteinases were characterized by azocaseinolytic, fibrinogenolytic and gelatinase activity and LAAO activity was assessed by enzyme activity on L-amino acids. Influence of these proteins on apoptosis and cell cycle in endothelial cells was analysed by flow cytometry. The angiogenic activity was determined by in vitro 3D spheroid assay, Matrigel tube forming assay, and in vivo agarose plug transformation in mice. Results: P-I metalloproteinases exhibited azocaseinolytic activity, cleaved α and partially β chain of fibrinogen, and displayed catalytic activity on gelatin. LAAO showed differential activity on L-amino acids. Flow cytometry analysis indicated that both P-I metalloproteinases and LAAO arrested the cells in G0/G1 phase and further induced both necrosis and apoptosis in endothelial cells. In vitro, P-I metalloproteinases and LAAO exhibited significant anti-angiogenic properties in 3D spheroid and Matrigel models by reducing sprout outgrowth and tube formation. Using agarose plug transplants in mice harbouring P-I metalloproteinases and LAAO we demonstrated a marked disruption of vasculature at the periphery. Conclusion: Our research suggests that P-I metalloproteinases and LAAO exhibit anti-angiogenic properties in vitro and in vivo.(AU)


Assuntos
Animais , Oxirredutases , Bothrops/fisiologia , Inibidores da Angiogênese , Venenos de Crotalídeos , Metaloproteases
4.
J. venom. anim. toxins incl. trop. dis ; 26: e20190058, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135137

RESUMO

Lack of complete genomic data of Bothrops jararaca impedes molecular biology research focusing on biotechnological applications of venom gland components. Identification of full-length coding regions of genes is crucial for the correct molecular cloning design. Methods: RNA was extracted from the venom gland of one adult female specimen of Bothrops jararaca. Deep sequencing of the mRNA library was performed using Illumina NextSeq 500 platform. De novo assembly of B. jararaca transcriptome was done using Trinity. Annotation was performed using Blast2GO. All predicted proteins after clustering step were blasted against non-redundant protein database of NCBI using BLASTP. Metabolic pathways present in the transcriptome were annotated using the KAAS-KEGG Automatic Annotation Server. Toxins were identified in the B. jararaca predicted proteome using BLASTP against all protein sequences obtained from Animal Toxin Annotation Project from Uniprot KB/Swiss-Pro database. Figures and data visualization were performed using ggplot2 package in R language environment. Results: We described the in-depth transcriptome analysis of B. jararaca venom gland, in which 76,765 de novo assembled isoforms, 96,044 transcribed genes and 41,196 unique proteins were identified. The most abundant transcript was the zinc metalloproteinase-disintegrin-like jararhagin. Moreover, we identified 78 distinct functional classes of proteins, including toxins, inhibitors and tumor suppressors. Other venom proteins identified were the hemolytic lethal factors stonustoxin and verrucotoxin. Conclusion: It is believed that the application of deep sequencing to the analysis of snake venom transcriptomes may represent invaluable insight on their biotechnological potential focusing on candidate molecules.(AU)


Assuntos
Animais , Bothrops , Bothrops/fisiologia , Proteoma , Venenos de Crotalídeos , Perfilação da Expressão Gênica , Metaloproteases , Transcriptoma , Biologia Molecular , Análise por Conglomerados , Sequenciamento de Nucleotídeos em Larga Escala
5.
Rev. ADM ; 76(3): 162-168, mayo-jun. 2019.
Artigo em Espanhol | LILACS | ID: biblio-1022153

RESUMO

Objetivo: Analizar la evidencia disponible sobre los componentes de los adhesivos dentinarios, las causas de la falla de la interface dentinaadhesivo, las alternativas para disminuir este fenómeno y aumentar el tiempo de vida de las restauraciones adhesivas. Material y métodos: Se realizó una revisión de la literatura de tipo descriptiva, la búsqueda de artículos se llevó a cabo en diferentes bases de datos, bibliotecas electrónicas, buscadores académicos y búsqueda manual en revistas. Se revisaron 118 artículos, de los cuales se seleccionaron 68. Conclusiones: La adhesión dentinaria sufre degradación hidrolítica y degradación proteolítica; el acondicionado ácido de la dentina promueve la liberación de metaloproteinasas y con ello el inicio de la degradación de la interface dentino-adhesivo, por el momento los adhesivos con MDP brindan la mejor opción ya que presentan los mejores resultados para contrarrestar la degradación, además de encontrarse comercialmente al alcance de los profesionistas. Los sistemas que presentan una simplificación de la técnica en ocasiones pueden ir en detrimento de los resultados. Aún es necesario realizar investigación que conduzca a reducir la falla de la interface adhesiva a largo plazo y obtener restauraciones óptimas, duraderas y libres de microfiltraciones (AU)


Objective: Analyze the available evidence on the components of dentin adhesives, the causes of failure of the dentin-adhesive interface, the alternatives to reduce this phenomenon and increase the lifetime of adhesive restorations. Material and methods: A review of the descriptive literature was made, the search of articles was carried out in different databases, electronic libraries, academic search engines and manual search in journals. 118 articles were reviewed, of which 68 were selected. Conclusions: Dentin adhesion suffers from hydrolytic and proteolytic degradation; the acid conditioning of dentine promotes the release of metalloproteinases and with it the beginning of the degradation of the dentin-adhesive interface, for the moment the adhesives with MDP offer the best option since they present the best results to counteract the degradation besides being commercially available to professionals. Simpli file Systems less can sometimes be detrimental to the results. It is still necessary to carry out investigations that leads to a reduction on the failure of the long-term adhesive interface and obtain optimal, durable and microfiltration-free restorations (AU)


Assuntos
Condicionamento Ácido do Dente , Adesivos Dentinários , Metaloproteases , Epidemiologia Descritiva , Falha de Restauração Dentária , Infiltração Dentária
6.
Odovtos (En línea) ; 21(1): 41-51, Jan.-Apr. 2019. graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1091470

RESUMO

Abstract 18. Introduction: Tooth development results from a highly coordinated epithelial-mesenchyme interaction in which mesenchyme cells originate the dental papilla and dental follicle, while ectodermal cells originate the enamel organ. Simultaneously, bone tissue is formed around the developing tooth, trapping it in a bony crypt. Tooth eruption requires the resorption of the coronal part of the bony crypt, followed by degradation of the lamina propria, most likely by metalloproteinases (MMPs) activity. Objectives: The aim of this research was to determine MMP-2 expression in the dental germ cells (ameloblasts, odontoblasts, dental papilla and dental follicle) and surrounding tissues (alveolar bone and lamina propria) of rat molars throughout the eruptive process. Material and Methods: A total of 24 rats (4,6,9,11,14 and 16 days old) were used in this study. MMP-2 was detected through immunohistochemistry. A qualitative analysis was performed to investigate the expression of MMP2 in the dental germ cells, lamina propria, and coronal and basal regions of the bony crypt. Results: MMP-2 expression was observed in the dental papilla cells, dental follicle, ameloblasts, odontoblasts and bone cells from the coronal and basal regions of the bony crypt. MMP-2 was also detected in the lamina propria during the mucosal penetration stage of tooth eruption. Conclusion: We conclude that MMP-2 may be important for the extracellular matrix rearrangement necessary for tooth development and secretion of its mineralized tissues. We also conclude that MMP-2 may play a role in the extensive tissue remodeling during the intra-and-extra-osseous phases of the tooth eruption process.


Resumen 24. Introducción: el desarrollo del diente resulta de una interacción epitelial-mesénquima altamente coordinada en la cual las células mesénquima originan la papila dental y el folículo dental, mientras que las células ectodérmicas originan el órgano del esmalte. Simultáneamente, el tejido óseo se forma alrededor del diente en desarrollo y lo atrapa en una cripta ósea. La erupción dentaria requiere la resorción de la parte coronal de la cripta ósea, seguida de la degradación de la lámina propia, muy probablemente por la actividad metaloproteinasas (MMPs). Objetivos: el objetivo de esta investigación fue determinar la expresión de MMP-2 en las células germinales dentales (ameloblastos, odontoblastos, papila dentaria y folículo dentario) y tejidos circundantes (hueso alveolar y lámina propia) de molares de rata a lo largo del proceso eruptivo. Material y métodos: en este estudio se utilizó un total de 24 ratas (4,6,9,11,14 y 16 días de edad). MMP-2 se detectó a través de inmunohistoquímica. Un análisis cualitativo fue realizado para investigar la expresión de MMP-2 en las células de germen dentales, el lámina propria, y las regiones coronales y basales de la cripta ósea. Resultados: la expresión de MMP2 fue observada en las células de la papila dental, el folículo dental, el ameloblastos, el odontoblastos y las células del las regiones basales y coronales de la cripta ósea. La expresión de MMP-2 también se detectó en la lámina propia durante la etapa de penetración de la mucosa de la erupción dental. Conclusión: Concluimos que MMP-2 puede ser importante para el cambio extracelular de la matriz necesario para el desarrollo del diente y la secreción de sus tejidos mineralizados. También concluimos que MMP-2 puede desempeñar un papel en la remodelación extensa del tejido durante las fases intra y extraósea del proceso de erupción dental.


Assuntos
Animais , Ratos , Assistência Odontológica , Metaloproteases , Erupção Dentária , Remodelação Óssea , Ameloblastos/patologia
7.
J. venom. anim. toxins incl. trop. dis ; 25: e148218, 2019. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1002496

RESUMO

Tityus serrulatus venom (Ts venom) is a complex mixture of several compounds with biotechnological and therapeutical potentials, which highlights the importance of the identification and characterization of these components. Although a considerable number of studies have been dedicated to the characterization of this complex cocktail, there is still a limitation of knowledge concerning its venom composition. Most of Ts venom studies aim to isolate and characterize their neurotoxins, which are small, basic proteins and are eluted with high buffer concentrations on cation exchange chromatography. The first and largest fraction from carboxymethyl cellulose-52 (CMC-52) chromatography of Ts venom, named fraction I (Fr I), is a mixture of proteins of high and low molecular masses, which do not interact with the cation exchange resin, being therefore a probable source of components still unknown of this venom. Thus, the present study aimed to perform the proteome study of Fraction I from Ts venom, by high resolution mass spectrometry, and its biochemical characterization, by the determination of several enzymatic activities. Methods: Fraction I was obtained by a cation exchange chromatography using 50 mg of crude venom. This fraction was subjected to a biochemical characterization, including determination of L-amino acid oxidase, phospholipase, hyaluronidase, proteases activities and inhibition of angiotensin converting enzyme (ACE) activity. Fraction I was submitted to reduction, alkylation and digestion processes, and the tryptic digested peptides obtained were analyzed in a Q-Exactive Orbitrap mass spectrometer. Data analysis was performed by PEAKS 8.5 software against NCBI database. Results: Fraction I exhibits proteolytic activity and it was able to inhibit ACE activity. Its proteome analysis identified 8 different classes of venom components, among them: neurotoxins (48%), metalloproteinases (21%), hypotensive peptides (11%), cysteine-rich venom protein (9%), antimicrobial peptides (AMP), phospholipases and other enzymes (chymotrypsin and lysozymes) (3%) and phosphodiesterases (2%). Conclusions: The combination of a proteomic and biochemical characterization strategies leads us to identify new components in the T. serrulatus scorpion venom. The proteome of venom´s fraction can provide valuable direction in the obtainment of components in their native forms in order to perform a preliminary characterization and, consequently, to promote advances in biological discoveries in toxinology.(AU)


Assuntos
Animais , Venenos de Escorpião , Produtos Biológicos , Proteoma , Metaloproteases , Neurotoxinas , Fosfolipases , Enzimas
8.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 45-52, Jan.-Feb. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-888079

RESUMO

O objetivo deste estudo foi avaliar a expressão das MMP-2 e MMP-9 no tecido laminar do casco e o perfil leucocitário de equinos submetidos à obstrução intraluminal do cólon menor. Realizaram-se laparotomia e obstrução do cólon menor de oito equinos hígidos, utilizando-se uma bola inserida no lúmem intestinal. A bola foi inflada à pressão de 80mmHg e a obstrução foi mantida por quatro horas. Foram realizadas coletas sanguíneas antes da obstrução (M0), imediatamente após a desobstrução (M4) e a cada 12 horas após M4, até completar 72 horas (M12, M24, M36, M48, M60 e M72). As biópsias de casco foram realizadas em M0, M4 e M72, e as amostras foram submetidas à análise zimográfica. Foi observado aumento nos leucócitos em M12 e M24, decorrente do aumento de neutrófilos segmentados e bastonetes, os quais diminuíram a partir de M36. Segundo a técnica zimográfica, não se observaram alterações nos valores de MMP-2 e -9, possivelmente devido à baixa intensidade das lesões ocasionadas no cólon menor. Com isso, conclui-se que as alterações inflamatórias decorrentes da obstrução do cólon menor não foram suficientes para ocasionar alterações na expressão das MMP-2 e -9 no tecido laminar podal.(AU)


The aim of this study was to evaluate the blood leukocytes and the MMP-2 and -9 expression in the hoof laminar tissue of horses undergoing intraluminal small colon obstruction. Laparotomy and the small colon obstruction was performed in eight healthy horses, inserting a ball in the intestinal lumen. The ball was inflated to 80 mmHg pressure and the occlusion was maintained for 4 hours. The blood was collectedBlood samples were taken before the obstruction (M0), immediately after intestinal clearance (M4), and every 12 hours until completeuntil 72 hours (M12, M24, M36, M48, M60 and M72). The hoof biopsies were performed at M0, M4, and M72 and the samples were subjected to zymography analysis. There was an increase in leukocytes in M12 and M24, due to the increase in segmented neutrophils and band neutrophils, which decreased as of M36. According to zymography technique not observed changes were not not observed in MMP-2 and -9, possibly due to the low intensity of the small colon lesions. Wherefore, it is concludedIn conclusion, that the inflammatory changes resulting from small colon obstruction were not enough to cause changes in the expression of MMP-2 and -9 in the hoof laminar tissue.(AU)


Assuntos
Animais , Biópsia , Metaloproteases/análise , Cavalos/anormalidades , Inflamação/classificação , Claudicação Intermitente/classificação
9.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-976031

RESUMO

Lachesis muta rhombeata (Lmr) is the largest venomous snake in Latin America and its venom contains mainly enzymatic components, such as serine and metalloproteases, L-amino acid oxidase and phospholipases A2. Metalloproteases comprise a large group of zinc-dependent proteases that cleave basement membrane components such as fibronectin, laminin and collagen type IV. These enzymes are responsible for local and systemic changes, including haemorrhage, myonecrosis and inflammation. This study aimed the isolation and enzymatic characterization of the first metalloprotease (Lmr-MP) from Lmr venom (LmrV). Methods and results: Lmr-MP was purified through two chromatographic steps and submitted to enzymatic characterization. It showed proteolytic activity on azocasein with maximum activity at pH 7.0-9.0. It was inhibited by EDTA (a metal chelator that removes zinc, which is essential for enzymatic activity) and no effect was observed with PMSF, iodoacetic acid or pepstatin (inhibitors of serine, cysteine and aspartyl proteases, respectively). Ca2+, Mg2+ and Ba2+ ions increased its activity, while Al3+, Cu2+, Ni2+ and Zn2+ inhibited it. Additionally, ZnCl2 showed a dose dependent inhibition of the enzyme. Lmr-MP activity was also evaluated upon chromogenic substrates for plasma kallikrein (S-2302), plasmin and streptokinase-activated plasminogen (S-2251) and Factor Xa (S-2222) showing the highest activity on S-2302. The activity in different solutions (5 mM or 50 mM ammonium bicarbonate, pH 7.8; 0.1% trifluoroacetic acid + 50% acetonitrile; phosphate buffer saline, pH 7.4; 50 mM sodium acetate, pH 4.0 or ammonium acetate pH 4.5) was also evaluated and the results showed that its activity was abolished at acidic pHs. Its molecular mass (22,858 Da) was determined by MALDI-TOF and about 90% of its primary structure was verified by high-resolution mass spectrometry using HCD and ETD fragmentations and database search against the sequence of closely related species. It is a novel enzyme which shared high identity with other snake venom metalloproteases (svMPs) belonging to the P-I group. Conclusion: The purification procedure achieved a novel pure highly active metalloprotease from LmrV. This new molecule can help to understand the metalloproteases mechanisms of action, the Lachesis envenoming, as well as to open new perspectives for its use as therapeutic tools.(AU)


Assuntos
Animais , Peptídeo Hidrolases , Venenos de Serpentes , Lachesis muta , Metaloproteases , Ácido Aspártico Proteases
10.
J. venom. anim. toxins incl. trop. dis ; 24: 36, 2018. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-976026

RESUMO

Animal poisons and venoms are sources of biomolecules naturally selected. Rhinella schneideri toads are widespread in the whole Brazilian territory and they have poison glands and mucous gland. Recently, protein from toads' secretion has gaining attention. Frog skin is widely known to present great number of host defense peptides and we hypothesize toads present them as well. In this study, we used a RNA-seq analysis from R. schneideri skin and biochemical tests with the gland secretion to unravel its protein molecules. Methods: Total RNA from the toad skin was extracted using TRizol reagent, sequenced in duplicate using Illumina Hiseq2500 in paired end analysis. The raw reads were trimmed and de novo assembled using Trinity. The resulting sequences were submitted to functional annotation against non-redundant NCBI database and Database of Anuran Defense Peptide. Furthermore, we performed caseinolytic activity test to assess the presence of serine and metalloproteases in skin secretion and it was fractionated by fast liquid protein chromatography using a reverse-phase column. The fractions were partially sequenced by Edman's degradation. Results: We were able to identify several classes of antimicrobial peptides, such as buforins, peroniins and brevinins, as well as PLA2, lectins and galectins, combining protein sequencing and RNA-seq analysis for the first time. In addition, we could isolate a PLA2 from the skin secretion and infer the presence of serine proteases in cutaneous secretion. Conclusions: We identified novel toxins and proteins from R. schneideri mucous glands. Besides, this is a pioneer study that presented the in depth characterization of protein molecules richness from this toad secretion. The results obtained herein showed evidence of novel AMP and enzymes that need to be further explored.(AU)


Assuntos
Anuros/fisiologia , Venenos , Metaloproteases , Serina Proteases , Secreções Corporais , Análise de Sequência de Proteína
11.
Arq. bras. med. vet. zootec ; 69(1): 123-129, jan.-fev. 2017. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-834162

RESUMO

As proteases fibrinolíticas são capazes de degradar coágulos de fibrina formados dentro dos vasos sanguíneos, evitando a trombose intravascular. Em animais, a tromboflebite, que acomete frequentemente os equinos, ocasiona, em seus casos graves, a obstrução jugular e também um edema de laringe, derivando a obstrução das vias aéreas, o que possibilita um edema cerebral, ocorrendo o óbito do animal. Devido ao fato de o tratamento ser de custo elevado, faz-se necessária a investigação de outras fontesde proteases fibrinolíticas com custos menores e com menos efeitos colaterais. Diante disso, este estudo tem como objetivo produzir e caracterizar proteases fibrinolíticas obtidas de Streptomyces parvulus DPUA 1573. Para produção da enzima, foi utilizado um planejamento fatorial 24 avaliando a concentração da farinha de soja (0,5, 1,0 e 1,5%) e da glicose (0, 0,5 e 1,0g/L), temperatura (28, 32 e 37ºC) e agitação (150, 200 e 250rpm) sobre a biomassa e a atividade fibrinolítica. Pode-se verificar que a protease fibrinolítica apresentou atividade máxima (835U/mL) nas condições de concentração de 1,5% de soja, 1g/L de glicose, 28°C e 150rpm com 48 horas de fermentação. A protease fibrinolítica obtida teve temperatura e pH ótimos de 55°C e pH 9,0, respectivamente. A atividade enzimática foi inibida pelo EDTA, pelo íon Fe2+ e pelo SDS, o que indicou a enzima ser uma metaloprotease. A linhagem Streptomyces parvulus DPUA 1573 foi capaz de produzir protease fibrinolítica, possuindo características bioquímicas favoráveis à aplicação na medicina veterinária e possivelmente humana.(AU)


Fibrinolytic proteases are able to degrade fibrin clot formed in the blood vessel, avoiding intravascular thrombosis. In animals, thrombophlebitis often affects horses, and in severe cases causes obstruction of the jugular and laryngeal edema leading to airway obstruction allowing cerebral edema resulting in the death of the animal. Since treatment is costly, the investigation of other sources of fibrinolytic proteases at lower cost and with fewer side effects is needed. Thus, this study aims to produce and characterize fibrinolytic proteases from Streptomyces parvulus DPUA 1573. For enzyme production, a factorial design was performed to evaluate 24 soybean flour concentration (0.5, 1.0 and 1.5%) and glucose (0, 0.5 and 1.0g/L), temperature (28, 32 and 37°C) and agitation (150, 200 and 250rpm) on biomass and fibrinolytic activity. Fibrinolytic protease showed maximum activity (835 U/mL) under these conditions: 1.5% soybean flour, 1g/L glucose, 28°C, and 150rpm 48 hours of fermentation. The optimal temperature was 55°C and optimal pH was 9.0. Fibrinolytic protease activity was inhibited by EDTA, the ion Fe2+, and by SDS, which indicated that the enzyme is a metallo-protease. The strain Streptomyces parvulus DPUA 1573 was able to produce fibrinolytic protease with biochemical characteristics favorable for application in veterinary and human medicine.(AU)


Assuntos
Fermentação , Fibrinolíticos , Peptídeo Hidrolases/análise , Streptomyces , Metaloproteases
12.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954849

RESUMO

Background: Snake venoms are a complex mixture of proteins, organic and inorganic compounds. Some of these proteins, enzymatic or non-enzymatic ones, are able to interact with platelet receptors, causing hemostatic disorders. The possible therapeutic potential of toxins with antiplatelet properties may arouse interest in the pharmacological areas. The present study aimed to purify and characterize an antiplatelet DC protein from Bothrops alternatus snake venom. Methods: The protein, called BaltDC (DC protein from B. alternatus snake venom), was purified by a combination of ion-exchange chromatography on DEAE-Sephacel column and gel filtration on Sephadex G-75. The molecular mass was estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE). The amino acid sequence of the N-terminal region was carried out by Edman degradation method. Platelet aggregation assays were performed in human platelet-rich plasma (PRP). Infrared (IR) spectroscopy was used in order to elucidate the interactions between BaltDC and platelet membrane. Results: BaltDC ran as a single protein band on SDS-PAGE and showed apparent molecular mass of 32 kDa under reducing or non-reducing conditions. The N-terminal region of the purified protein revealed the amino acid sequence IISPPVCGNELLEVGEECDCGTPENCQNECCDA, which showed identity with other snake venom metalloproteinases (SVMPs). BaltDC was devoid of proteolytic, hemorrhagic, defibrinating or coagulant activities, but it showed a specific inhibitory effect on platelet aggregation induced by ristocetin and epinephrine in PRP. IR analysis spectra strongly suggests that PO 3 2 − groups, present in BaltDC, form hydrogen bonds with the PO 2 − groups present in the non-lipid portion of the membrane platelets. Conclusions: BaltDC may be of medical interest since it was able to inhibit platelet aggregation.(AU)


Assuntos
Animais , Venenos de Serpentes , Análise Espectral , Agregação Plaquetária , Bothrops , Transtornos Hemostáticos , Metaloproteases , Dodecilsulfato de Sódio , Eletroforese em Gel de Poliacrilamida
13.
J. venom. anim. toxins incl. trop. dis ; 23: 35, 2017. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954832

RESUMO

Background: Because jellyfish are capable of provoking envenomation in humans, they are considered hazardous organisms. Although the effects of their toxins are a matter of concern, information on the venom components, biological activity and pathological mechanisms are still scarce. Therefore, the aim of the present study was to investigate a serine protease component of Nemopilema nomurai jellyfish venom (NnV) and unveil its characteristics. Methods: To determine the relationship between fibrinolytic activity of NnV and the serine protease, fibrin zymography was performed using metalloprotease and serine protease inhibitors. The biochemical characterization of serine proteases of NnV were determined by the amidolytic assay. Fractions with fibrinolytic activity were obtained by DEAE cation exchange column. Results: NnV displayed fibrinolytic activities with molecular masses of approximately 70, 35, 30, and 28 kDa. The fibrinolytic activity of NnV was completely obliterated by phenylmethylsulfonyl fluoride, a prototype serine protease inhibitor. Based on amidolytic assays using chromogenic substrates specific for various kinds of serine proteases, NnV predominantly manifested a chymotrypsin-like feature. Its activity was completely eliminated at low pH (< 6) and high temperatures (> 37 °C). Some metal ions (Co2+, Cu2+, Zn2+ and Ni2+) strongly suppressed its fibrinolytic activity, while others (Ca2+ and Mg2+) failed to do so. Isolation of a serine protease with fibrionolytic activity from NnV revealed that only p3 showed the fibrinolytic activity, which was completely inhibited by PMSF. Conclusion: The present study showed that N. nomurai jellyfish venom has a chymotrypsin-like serine protease with fibrinolytic activity. Such information might be useful for developing clinical management of jellyfish envenomation and pharmacological agents with therapeutic potential for thrombotic diseases in the future.(AU)


Assuntos
Animais , Fluoreto de Fenilmetilsulfonil , Técnicas In Vitro , Fibrina , Quimotripsina , Venenos de Cnidários , Metaloproteases , Enzimas , Serina Proteases
14.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954813

RESUMO

Abstract Brown spiders are venomous arthropods that use their venom for predation and defense. In humans, bites of these animals provoke injuries including dermonecrosis with gravitational spread of lesions, hematological abnormalities and impaired renal function. The signs and symptoms observed following a brown spider bite are called loxoscelism. Brown spider venom is a complex mixture of toxins enriched in low molecular mass proteins (4-40 kDa). Characterization of the venom confirmed the presence of three highly expressed protein classes: phospholipases D, metalloproteases (astacins) and insecticidal peptides (knottins). Recently, toxins with low levels of expression have also been found in Loxosceles venom, such as serine proteases, protease inhibitors (serpins), hyaluronidases, allergen-like toxins and histamine-releasing factors. The toxin belonging to the phospholipase-D family (also known as the dermonecrotic toxin) is the most studied class of brown spider toxins. This class of toxins single-handedly can induce inflammatory response, dermonecrosis, hemolysis, thrombocytopenia and renal failure. The functional role of the hyaluronidase toxin as a spreading factor in loxoscelism has also been demonstrated. However, the biological characterization of other toxins remains unclear and the mechanism by which Loxosceles toxins exert their noxious effects is yet to be fully elucidated. The aim of this review is to provide an insight into brown spider venom toxins and toxicology, including a description of historical data already available in the literature. In this review article, the identification processes of novel Loxosceles toxins by molecular biology and proteomic approaches, their biological characterization and structural description based on x-ray crystallography and putative biotechnological uses are described along with the future perspectives in this field.(AU)


Assuntos
Animais , Venenos de Aranha , Aranhas , Toxicologia , Metaloproteases , Serina Proteases
15.
Oncol. clín ; 22(3): 89-95, 2017. ilus
Artigo em Espanhol | LILACS | ID: biblio-909368

RESUMO

El cáncer de mama (CM) es uno de los más frecuentes en Argentina y primera causa de muerte por cáncer en mujeres. Las metaloproteasas son endopeptidasas que degradan la matriz extracelular, facilitando la invasión tumoral y las metástasis. Se observó la utilidad de la MMP-9 como un marcador diagnóstico, pronóstico y de seguimiento en pacientes con CM. La MMP-11 parece tener un efecto dual en cáncer, su aumento se asocia a un incremento de tumores primarios de mama, pero con una represión en el desarrollo de metástasis. En el trabajo se analizaron los polimorfismos de nucleótido único (SNPs) Arg574Pro del gen MMP-9 y Ala38Val del MMP-11, con relación a las metástasis de CM. Se tomaron muestras de sangre de pacientes con CM metastásico y no metastásico (controles), con receptores de progesterona+, estrógeno+ y HER2-neu+/-. Se extrajo ADN de 25 muestras y se diseñaron cebadores para amplificar la región que contenían los SNPs Arg574Pro y Ala38Val. Se estandarizó la PCR para los SNPs correspondientes, aclarando que el cebador izquierdo que amplifica Arg574Pro, hibrida sobre los polimorfismos rs146961494 y rs35691798. Se realizó el análisis de las enzimas de restricción, MbiI para Arg574Pro y AatII para Ala38Val. Se concluye que para MMP-9, el polimorfismo presenta el alelo C como el G sólo en el grupo metastásico. En cuanto al gen MMP-11, se encuentra en alta frecuencia la variante alélica T, la cual no corresponde al alelo ancestral, indicando que puede estar su función/expresión relacionada con el carcinoma mamario. Estos hallazgos son preliminares (AU)


Breast cancer (BC) is one of the most common in Argentina and the leading cause of cancer death in women. Metalloproteases are endopeptidases that degrade the extracellular matrix, facilitating tumor invasion and metastases. The utility of MMP-9 was observed as a diagnostic, prognostic and follow-up marker in BC patients. MMP-11 appears to have a dual effect on cancer. High levels are associated with an increase in primary breast tumors, but with repression in the development of metastases. Arg574Pro SNPs of the MMP-9 gene and Ala38Val of MMP-11 gene were analyzed in relation to BC metastases. Blood samples were taken from patients with BC metastatic and non-metastatic (controls), with progesterone+, estrogen+ and HER2-neu+/- receptors. DNA from 25 samples was drawn and primers were designed to amplify the region containing the SNPs Arg574Pro and Ala38Val. PCR was standardized for the corresponding SNPs, clarifying that the Arg574Pro amplified left primer hybridizes to polymorphisms rs146961494 and rs35691798. The restriction enzyme analysis was performed, MbiI for Arg574Pro and AatII for Ala38Val. It is concluded that for MMP-9, the polymorphism presents the C allele as the G only in the metastatic group. As for the MMP-11 gene, the allelic variant T is found in high frequency, which does not correspond to the ancestral allele, indicating that its function/expression may be related to mammary carcinoma. These findings are preliminary (AU)


Assuntos
Humanos , Neoplasias da Mama , Metástase Neoplásica , Polimorfismo de Nucleotídeo Único , Metaloproteases
16.
Motriz (Online) ; 23(4): e1017107, 2017. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-895018

RESUMO

AIMS: The aim of the present study was to investigate the influence of resistance training (RT) and hormone replacement (HR) on MMP-2 activity, biomechanical and physical properties bone of ovariectomized (OVX) rats. METHODS: Sprague-Dawley female rats were grouped into six experimental groups (n = 11 per group): sham-operated sedentary (SHAM Sed), ovariectomized sedentary (OVX Sed), sham-operated resistance training (SHAM RT), ovariectomized resistance training (OVX RT), ovariectomized sedentary hormone replacement (OVX Sed-HR), and ovariectomized resistance training hormone replacement (OVX RT-HR). HR groups received implanted silastic capsules with a 5% solution of 17ß-estradiol (50 mg 17ß-estradiol/ml of sunflower oil). In a 12-week RT period (27 sessions; 4-9 climbs) the animals climbed a 1.1 m vertical ladder with weights attached to their tails. Biomechanical and physical bone analyses were performed using a universal testing machine, and MMP-2 activity analysis was done by zymography. RESULTS: Bone density and bone mineral content was higher in the RT and HR groups. The MMP-2 activity was higher in the RT and HR groups. The biomechanical analysis (stiffness, fracture load and maximum load) demonstrated better bone tissue quality in the RT associated with HR. CONCLUSION: The RT alone as well as when it is associated with HR was efficient in increasing MMP-2 activity, biomechanical and biophysical properties bone of ovariectomized rats.(AU)


Assuntos
Animais , Feminino , Ratos , Osteoporose , Ovariectomia , Terapia de Reposição Hormonal , Metaloproteases/administração & dosagem , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Treinamento de Força
17.
Braz. j. oral sci ; 15(4): 304-307, Oct.-Dec. 2016. tab
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-875864

RESUMO

Polymorphisms in matrix metalloproteinases (MMPs) genes have been associated with several pathologies, including dental implant loss. MMP-3 is crucial to the connective tissue remodeling process. The objective of this study was to investigate the possible relationship between -1612 MMP-3 polymorphism and the early implant failure. A sample of 240 non-smokers was divided: test group 120 patients with one or more early failed implants and control group 120 patients with one or more healthy implants. Genomic DNA from oral mucosa was analyzed by PCR-RFLP. No association of early implant loss with genotypes and alleles of the -1612 polymorphism in MMP-3 were found by the Chi-squared test. Only the presence of the -1612 polymorphism of MMP-3 is not a genetic risk factor for early loss of implants (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Metaloproteinase 3 da Matriz , Metaloproteases , Polimorfismo Genético , Fatores de Risco , Implantes Dentários
18.
Braz. dent. j ; 27(4): 442-445, July-Aug. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-794610

RESUMO

Abstract This study evaluated the effect of matrix metalloproteinase (MMP) inhibitors - 2% (CHX) and sodium fluoride (NaF) (5000 ppm) - on microtensile bond strength (μTBS) of composite resin to Er:YAG laser-irradiated dentin after chemical degradation of the bond interface. The occlusal surface of forty sound human molars was removed exposing the dentin surface (n=10), which was polished, irradiated with Er:YAG laser, acid etched and dried. Twenty specimens were rewetted with 2% CHX (control group) and 20 were rewetted with NaF (5000 ppm). The adhesive system was applied and a 4-mm-high plateau of light-cured composite resin was built up. Resin-dentin sticks were obtained with a rectangular cross-sectional area (0.8-1 mm2) and were either stored in water at 37 ?#61616;C for 24 h or submitted to chemical degradation. For chemical degradation, they were immersed in 10% NaOCl aqueous solution for 5 h and rinsed in water for 1 h. The sticks were submitted to microtensile test in a mechanical testing machine at 0.5 mm/min until failure. Fracture pattern was analyzed using SEM. μTBS values were calculated in MPa and submitted to analysis of variance ANOVA (α=0.05). The variance analysis showed that the 'MMP inhibitor' and 'degradation' factors (p=0.214 and p=0.093, respectively) and interaction between the factors were not statistically significant (p=0.143). Mixed failure predominated in all groups. In conclusion, the 2% CHX and NaF 5000 ppm presented similar μTBS of composite resin to laser-irradiated dentin before and after chemical degradation.


Resumo Este estudo avaliou o efeito dos inibidores de metaloproteinase, clorexidina 2% e fluoreto de sódio (5000 ppm), na resistência de união entre a dentina irradiada por laser Er:YAG e a resina composta após a degradação química da interface de união. A superfície oclusal de quarenta molares humanos hígidos (n=10) foi removida expondo uma superfície de dentina, que foi polida, irradiada com laser Er:YAG, condicionada com ácido e seca. Vinte espécimes foram re-umedecidos com clorexidina 2% (Grupo controle) e 20 com fluoreto de sódio (5000 ppm). O sistema adesivo foi aplicado e um platô de resina composta fotopolimerizável de 4 mm de altura foi construído. Palitos de resina-dentina foram obtidos com secção transversal retangular (0,8-1 mm2). Eles foram armazenados em água (24 h a 37 ?#61616;C) ou submetidos a degradação química. Para a degradação química, foram imersos em solução aquosa de hipoclorito de sódio a 10% durante 5 horas e lavados em água durante 1 h. Os palitos foram submetidos ao teste de microtração em uma máquina de ensaios mecânicos a 0,5 mm/min até a fratura. O padrão de fratura foi analisado em MEV. Os valores de resistência de união foram calculados em MPa e submetidos à análise de variância ANOVA (α=0,05). A análise de variância mostrou que os fatores inibidor de metaloproteinases e degradação (p=0,214 e p=0,093, respectivamente), e a interação entre os fatores não foram estatisticamente significantes (p=0,143). A predominância de falha mista foi detectada para todos os grupos. Em conclusão, a clorexidina a 2% e fluoreto de sódio (ppm 5000) apresentaram resistência de união entre dentina irradiada e resina composta semelhante antes e após a degradação química.


Assuntos
Resinas Compostas , Lasers de Estado Sólido , Metaloproteases/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Resistência à Tração , Metaloproteases/metabolismo
19.
São Paulo; s.n; 2016. [120] p. ilus, tab, graf.
Tese em Português | LILACS | ID: biblio-870905

RESUMO

Micose fungoide poiquilodérmica (MFp) é uma variante clínica de micose fungoide (MF). É mais indolente e caracterizada pela presença da poiquilodermia. As metaloproteinases (MMP) e seus inibidores específicos TIMP (Tissue Inhibitors of Metaloproteinases) estão envolvidos na oncogênese. Especificamente as MMP2 e MMP9 e seus inibidores, TIMP-2 e TIMP-1, respectivamente, foram relacionados ao prognóstico em tumores. Poucos trabalhos estudaram MMP e nenhum estudou a ação dos TIMP na MF. Objetivos: avaliar a relação entre MMP2 e MMP9 e seus inibidores TIMP2 e TIMP1 e a agressividade da MF e descrever a casuística de micose fungoide poiquilodérmica no ambulatório de linfomas cutâneos da Divisão de Clínica Dermatológica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Métodos: análise retrospectiva de 54 casos de MFp, sendo 25 de MFp localizada 14 de MFp generalizada e 15 de MFp mista. Para análise das MMP e TIMP, os grupos de MFp foram comparados com 7 amostras de pele normal (PN), 10 casos de MF clássica inicial (MFi), 9 casos de MF tumoral não-transformada (MFT nt) e 10 de MF tumoral transformada (MFT t). Resultados: A proporção de mulheres: homens foi 2,44. MFp apresentou maior tempo entre os primeiros sintomas e o diagnóstico. MFpG apresentou maior prevalência de lesões do tipo pitiríase liquenoide crônica (PLC) (79%). Houve alta prevalência de MF hipocromiante (62%) no grupo MFp mista. A histologia da MFp apresentou características típicas de MF e, adicionalmente, atrofia, telangectasias e derrame pigmentar, específicos da forma poiquilodérmica. Na imuno-histoquímica predominou o fenótipo CD3+, CD4+, CD7-, CD8- em todos os grupos, e MFp apresentou significantemente menor predomínio do fenótipo CD8+ que o grupo MFi. O grupo MFpG apresentou baixa positividade para pesquisa de clonalidade T da pele (12,5%). A MMP2 esteve mais presente na epiderme em MFi e MFp relativamente a MFT. Na derme superficial, os grupos MFi e MFp...


Poikilodermatous mycosis fungoides (pMF) is a clinical variant of mycosis fungoides (MF). It is more indolent than classic MF and is characterized by the presence of poikiloderma. The matrix metalloproteinases (MMPs) and their specific inhibitors TIMP (Tissue Inhibitors of Metalloproteinases) are involved in oncogenesis. Specifically, MMP2 and MMP9 and their inhibitors, TIMP-2 and TIMP-1, respectively, have been related to prognosis in tumors. There are few studies on MMP and none on the role of TIMPs in MF. Objectives: To evaluate if there is a relationship between the presence and activity of MMP2 and MMP9 and their inhibitors TIMP2 and TIMP1, and the aggressiveness of MF. To describe a casuistic of poikilodermatous mycosis fungoides in an outpatient clinic in the Dermatological Division of Hospital das Clinicas of University of Sao Paulo Medical School. Methods: Retrospective analysis of 54 cases of pMF, this included 25 localized pMF (LpMF), 14 generalized pMF (GpMF) and 15 mixed pMF. For the analysis of MMPs and TIMPs, the pMF groups were compared with 7 normal skin samples (NS), 10 cases of initial classical MF (cMF), 9 cases of non-transformed tumor MF (nt MFT) and 10 transformed tumor MF (t MFT). Results: The proportion of women : men was 2.44. The pMFs groups showed a longer period of time from the first symptoms to the diagnosis than the cMF group. The GpMF group had a higher incidence of pityriasis lichenoides chronica-like lesions (PLC) (79%) than the other groups. There was a high incidence of hypopigmented MF (62%) in the mixed pMF group. Histology showed typical characteristics of MF and, additionally, atrophy, telangiectasia and pigmentary alterations compatible with pMF. At immunohistochemistry the cases were predominantly CD3+, CD4+, CD7-, CD8- phenotype in all groups, and the pMF groups had a significantly lower prevalence of CD8+ phenotype than the cMF group. The GPMF group showed low positivity for clonality of the T-cell...


Assuntos
Humanos , Masculino , Feminino , Imuno-Histoquímica , Linfoma Cutâneo de Células T , Metaloproteases , Micose Fungoide , Prognóstico , Dermatopatias , Inibidores Teciduais de Metaloproteinases
20.
São Paulo; s.n; s.n; 2016. 130 p. tab, graf, ilus.
Tese em Português | LILACS | ID: biblio-846663

RESUMO

A desnutrição proteica (DP) pode ocasionar alterações na matriz extracelular (MEC) de diferentes órgãos e tecidos, inclusive o hematopoético, com comprometimento funcional. Estudos do nosso laboratório demonstraram, em modelo murino de DP, aumento da expressão proteica de fibronectina (FN) no estroma medular ósseo in vivo, principalmente na região subendosteal (local de fixação da célula tronco progenitora hemopoética). Já in vitro, no estroma medular ósseo, observou-se tanto o aumento quanto a diminuição de FN e a presença de suas isoformas. Essas alterações de FN parecem estar envolvidas com a hipoplasia da medula óssea (MO) em camundongos desnutridos. As modificações quantitativas de FN podem ser devidas: (i) à ação das metaloproteinases de matriz (MMP) responsáveis pela degradação das proteínas da MEC; (ii) aos inibidores de metaloproteinases (TIMP) que regulam a degradação da MEC; (iii) às alterações transcricionais, reguladas pela via de AKT/mTOR, que controla os splicing alternativos na FN, resultando em isoformas dessa proteína; (iv) a processos pós-transcricionais modulados por LC3, que aumenta a tradução do RNAm de FN. Assim, o objetivo deste estudo foi elucidar os mecanismos que alteram o turnover de FN no estroma medular ósseo em modelo murino de DP. Utilizamos camundongos, C57BL/6J machos, adultos, separados em dois grupos: controle e desnutrido, alimentados, ad libitum, com ração contendo 12% e 2% de proteína, respectivamente. Após cinco semanas de indução à desnutrição os camundongos foram eutanasiados, e coletado o material biológico. Avaliamos: o estado nutricional, o hematológico, a histologia da MO femoral bem como a determinação imunohistoquímica da FN, MMP-2 e MMP-9, determinação da expressão de FN e suas isoformas em células totais da MO, o estabelecimento do estroma medular ósseo in vitro, por 28 e 35 dias de cultivo. A partir das culturas foram avaliadas a expressão de RNAm de FN e suas isoformas, MMP-2, MMP-9, TIMP-1, TIMP-2, AKT, mTOR e LC3α e ß, quantificação de MMP-2, MMP-9, TIMP-1, TIMP-2,TNFα, TGFß e IL-1ß e determinação de LC3ß e proteínas da via de AKT/mTOR. Não observamos alterações na expressão do RNAm de FN e suas isoformas ex vivo e in vitro, mas um aumento da deposição de FN na MO.Também não observamos modificações na imunolocalização de MMP-2 e MMP-9 na MO e na atividade dessas proteínas no sobrenadante de culturas de células estromais in vitro, mas houve aumento da expressão do RNAm de MMP-9 em 28 dias de cultivo. Não detectamos alterações na expressão de RNAm e na concentração de TIMP-1 e TIMP-2 no sobrenadante das culturas. Houve redução significativa de TNFα e TGFß no sobrenadante das culturas de 28 dias. Observamos aumento da expressão do RNAm de mTOR em culturas de 28 dias e LC3α e LC3ß em 35 dias de células estromais. Encontramos menor fosforilação de PI3K, AKT, PTEN, mTOR e mTOR total e aumento de LC3ß em culturas de 28 dias, mas redução de LC3ß em 35 dias. Em função dos dados inferimos que a DP conduz a alterações da FN que não estão relacionadas à ação de MMPs e TIMPs e sim a modificações de LC3ß e da via de AKT/mTOR


Protein malnutrition (PM) can lead changes in extracellular matrix (ECM) from several organs and tissues, including hematopoietic, with functional impairments. Research from our laboratory demonstrated, in a murine model of protein malnutrition, increase in proteic expression of fibronectin (FN) in vivo bone marrow stroma, principally in subendosteal region (attachment site of hematopoietic stem/progenitor cell - HSPC). It was observed as both an increase and a decrease in the presence of FN and its isoforms in vitro bone marrow stroma. These FN changes seem to be related to bone marrow (BM) hypoplasia in malnourished mice. Quantitative FN changes may be due to: (i) action of matrix metalloproteinases (MMP) responsible for ECM proteins degradation; (ii) tissue inhibitors of metalloproteinases (TIMP) that regulate ECM degradation; (iii) transicional changes regulated by AKT/mTOR pathway, which controls alternative splicing in FN, resulting in isoforms from this protein; (iv) post-transcriptional processes modulated by LC3 that increases FN mRNA translation. Therefore, the aim of this study was to elucidade the mechanisms that changes the FN turnover in bone marrow stroma in a murine model of PM. C57BL/6J, adult and male mice were used and divided into two groups: control and malnourished, fed ad libitum with ration containing 12% and 2% of protein, respectively. After five weeks of induction malnutrition, mice were euthanized and the biological material was collected. We evaluated: nutritional and hematologic status, the femoral BM histology, immunohistochemistry determination of FN, MMP-2 and MMP-9, the FN and its isoforms expression determination in total BM cells, establishment of in vitro bone marrow stroma for 28 and 35 days of culture. From the cultures were evaluated FN mRNA expressions and its isoforms, MMP-2, MMP-9, TIMP-1, TIMP-2, AKT, mTOR, LC3α and ß, quantification of MMP-2, MMP-9, TIMP-1, TIMP-2,TNFα, TGFß and IL-1ß and determination of LC3ß and AKT/mTOR proteins. No changes were observed, ex vivo and in vitro, in the expression of FN mRNA and its isoforms, but there was a FN deposition increase in BM. We did not observe modifications in MMP-2 e MMP-9 immunolocalization in BM and in these proteins activity in the supernatant of in vitro stromal cell culture, but there was an increase in MMP-9 mRNA expression after 28 days of culture. We did not detect changes in mRNA and in TIMP-1 and TIMP-2 expressions in the supernatant of cultures. There was significant reduction of TNFα and TGFß in the cultures supernatant of 28 days. We observed an increase of mTOR RNAm in 28 days cultures and also LC3α and LC3ß in stromal cells with 35 days. We found lower phosphorylation of PI3K, AKT, PTEN, mTOR e total mTOR and an LC3ß increase in 28 days cultures, yet an LC3ß reduction in 35 days. According to the data we conclude that PM leads to FN changes that are not related to MMPs and TIMPs actions, but the LC3ß and AKT/mTOR pathway modifications


Assuntos
Animais , Masculino , Camundongos , Medula Óssea , Fibronectinas , /induzido quimicamente , /complicações , Hematologia , Metaloproteinases da Matriz/síntese química , Metaloproteases/síntese química , Proteínas Serina-Treonina Quinases/análise
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