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1.
Nat Commun ; 11(1): 4659, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938936

RESUMO

The αvß6 integrin plays a key role in the activation of transforming growth factor-ß (TGFß), a pro-fibrotic mediator that is pivotal to the development of idiopathic pulmonary fibrosis (IPF). We identified a selective small molecule αvß6 RGD-mimetic, GSK3008348, and profiled it in a range of disease relevant pre-clinical systems. To understand the relationship between target engagement and inhibition of fibrosis, we measured pharmacodynamic and disease-related end points. Here, we report, GSK3008348 binds to αvß6 with high affinity in human IPF lung and reduces downstream pro-fibrotic TGFß signaling to normal levels. In human lung epithelial cells, GSK3008348 induces rapid internalization and lysosomal degradation of the αvß6 integrin. In the murine bleomycin-induced lung fibrosis model, GSK3008348 engages αvß6, induces prolonged inhibition of TGFß signaling and reduces lung collagen deposition and serum C3M, a marker of IPF disease progression. These studies highlight the potential of inhaled GSK3008348 as an anti-fibrotic therapy.


Assuntos
Butiratos/farmacologia , Fibrose Pulmonar Idiopática/tratamento farmacológico , Integrinas/antagonistas & inibidores , Naftiridinas/farmacologia , Pirazóis/farmacologia , Pirrolidinas/farmacologia , Administração por Inalação , Animais , Antígenos de Neoplasias/metabolismo , Bleomicina/toxicidade , Butiratos/administração & dosagem , Butiratos/metabolismo , Butiratos/farmacocinética , Colágeno/metabolismo , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/patologia , Integrinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Naftiridinas/administração & dosagem , Naftiridinas/metabolismo , Naftiridinas/farmacocinética , Pirazóis/administração & dosagem , Pirazóis/metabolismo , Pirazóis/farmacocinética , Pirrolidinas/administração & dosagem , Pirrolidinas/metabolismo , Pirrolidinas/farmacocinética , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Tomografia Computadorizada de Emissão de Fóton Único , Fator de Crescimento Transformador beta/metabolismo , Pesquisa Médica Translacional
2.
Int J Oral Maxillofac Implants ; 35(5): 917-923, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32991641

RESUMO

PURPOSE: Compaction of particulated grafts is done manually; thus, the effect of compression force on bone regeneration remains unclear. The aim of this study was to evaluate the impact of two different compression forces on the consolidation of particulated bovine hydroxyapatite. MATERIALS AND METHODS: Two titanium cylinders were fixed on the calvarium of eight New Zealand rabbits. Both defects were filled with particulated bovine hydroxyapatite subjected to a compression force of 0.7 kg/cm2 or 1.6 kg/cm2 before being covered with a resorbable collagen membrane. A handheld device that uses a spring to control the compression force applied by the plugger was used. At 6 weeks, histomorphometry of the area immediately adjacent to the calvaria bone and to the collagen membrane was performed. RESULTS: It was shown that next to the calvaria, the bone volume per tissue volume (BV/TV) was 29.0% ± 8.8% and 27.6% ± 8.2% at low and high compression force, respectively; the bone-to-biomaterial contact (BBC) was 58.2% ± 25.0% and 69.3% ± 22.9%, respectively (P > .05). In the corresponding area next to the collagen membrane, BV/TV was 4.9% ± 5.1% and 5.7% ± 4.7%, and the BBC was 18.3% ± 20.8% and 20.1% ± 15.9%, respectively (P > .05). In addition, the number and area of blood vessels were not significantly affected by compression force. CONCLUSION: Both compression forces applied resulted in similar consolidation of bovine hydroxyapatite expressed by new bone formation and vascularization based on a rabbit calvaria augmentation model.


Assuntos
Regeneração Óssea , Durapatita , Animais , Materiais Biocompatíveis , Bovinos , Colágeno , Coelhos , Crânio/cirurgia
3.
Nat Commun ; 11(1): 4520, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908154

RESUMO

Tumor extracellular matrix has been associated with drug resistance and immune suppression. Here, proteomic and RNA profiling reveal increased collagen levels in lung tumors resistant to PD-1/PD-L1 blockade. Additionally, elevated collagen correlates with decreased total CD8+ T cells and increased exhausted CD8+ T cell subpopulations in murine and human lung tumors. Collagen-induced T cell exhaustion occurs through the receptor LAIR1, which is upregulated following CD18 interaction with collagen, and induces T cell exhaustion through SHP-1. Reduction in tumor collagen deposition through LOXL2 suppression increases T cell infiltration, diminishes exhausted T cells, and abrogates resistance to anti-PD-L1. Abrogating LAIR1 immunosuppression through LAIR2 overexpression or SHP-1 inhibition sensitizes resistant lung tumors to anti-PD-1. Clinically, increased collagen, LAIR1, and TIM-3 expression in melanoma patients treated with PD-1 blockade predict poorer survival and response. Our study identifies collagen and LAIR1 as potential markers for immunotherapy resistance and validates multiple promising therapeutic combinations.


Assuntos
Adenocarcinoma de Pulmão/tratamento farmacológico , Antineoplásicos Imunológicos/farmacologia , Linfócitos T CD8-Positivos/imunologia , Colágeno/metabolismo , Resistencia a Medicamentos Antineoplásicos/imunologia , Neoplasias Pulmonares/tratamento farmacológico , Receptores Imunológicos/metabolismo , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/patologia , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Animais , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Conjuntos de Dados como Assunto , Modelos Animais de Doenças , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/imunologia , Matriz Extracelular/patologia , Feminino , Técnicas de Silenciamento de Genes , Células HEK293 , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Humanos , Pulmão/imunologia , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Transgênicos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA-Seq , Receptores Imunológicos/genética
4.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(5): 640-646, 2020 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-32897197

RESUMO

OBJECTIVE: To clarify the molecular signaling mechanism underlying the inhibitory effect of metformin on transforming growth factor-ß1 (TGF-ß1)-stimulated collagen I production in rat biliary fibroblasts. METHODS: Primary biliary fibroblasts were isolated under aseptic condition from 50 Sprague-Dawley rats (half male and half female), and microscopic observation identified no obvious difference in the morphology or viability of the cells from rats with different sexes or body weight. The cells were treated with TGF-ß1 (10 ng/mL), Smad3 siRNA+TGF-ß1, CTGF siRNA+TGF-ß1, metformin (10 mmol/L)+ TGF-ß1, or Compound C (10 µmol/L)+metformin+TGF-ß1. The expressions of CTGF and collagen I in the treated cells were determined using ELISA kit or Western blotting; the phorsphorylated and total Smad3 and AMPK expressions were detected using immunoblotting. RESULTS: TGF-ß1 time- and dose-dependently induced collagen I production in rat biliary fibroblasts. The activated AMPK by metformin dose-dependently inhibited TGF-ß1-induced collagen I production. Pre-incubation of cells with the AMPK inhibitor Compound C restored the inhibitory effect of AMPK on TGF-ß1-induced collagen I secretion (P < 0.01). Activation of AMPK by metformin significantly reduced TGF-ß1-induced collagen I production by suppressing Smad3-driven CTGF expression (P < 0.01), and the application of Compound C reversed such changes in the fibroblasts (P < 0.01). CONCLUSIONS: Metformin inhibits TGF-ß1-stimulated collagen I production by activating AMPK and inhibiting Smad3- driven CTGF expression in rat biliary fibroblasts.


Assuntos
Fibroblastos , Animais , Células Cultivadas , Colágeno , Feminino , Masculino , Metformina , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Proteína Smad3 , Fator de Crescimento Transformador beta1
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(6): 684-692, 2020 Jun 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32879126

RESUMO

OBJECTIVES: To evaluate the repairing ability of nano-pearl powder bone substitute in rabbit with defect of distal femur bone. METHODS: Thirty-two New Zealand rabbits were randomly divided into four groups: a nano-pearl powder/recombinant human bone morphogenetic protein 2 (rhBMP-2)/hyaluronic acid group, a nano-pearl powder/hyaluronic acid group, a nano-pearl powder group and a blank control group (n=8 in each group). A defect with the diameter of 7 mm and height of 10 mm was prepared at the distal femoral metaphysis line of the rabbit.Different bone substitutes were planted, and the effect of repair was evaluated by macroscopic observation, imaging examination, and histopathological examination. RESULTS: The results of imageology showed that: the bone repairing effect in the nano-pearl powder/rhBMP-2/hyaluronic acid group was better than that in the pure pearl powder group and the nano-pearl powder/hyaluronic acid group, and which in the 3 experimental groups was better than that in the blank control group; The results of histology showed that: at the 4th, 8th and 12th weeks after the modeling operation, the speed of bone repair in the nano-pearl powder/rhBMP-2/hyaluronic acid group was faster than that in the pure pearl powder group and the nano-pearl powder/hyaluronic acid group, and which in the blank control group was far slower than that in the 3 experimental groups. The results of immunohistochemistry staining for osteocalcin antibody showed that: the osteogenic effect in the nano-pearl powder/rhBMP-2/hyaluronic acid group was better than that in the pure pearl powder group and the nano-pearl powder/hyaluronic acid group (both P<0.05); there was no significant difference between the nano-pearl powder/hyaluronic acid group and the pure pearl powder group (P>0.05); however, there was significant difference between the pure pearl powder group and the blank control group (P<0.05). According to the staining results of Type I collagen antibody, there was no significant difference in the osteogenic effect between the nano-pearl powder/rhBMP-2/hyaluronic acid group and the nano-pearl powder/hyaluronic acid group (P>0.05), but the osteogenic effect in the nano-pearl powder/hyaluronic acid group was better than that in the pure pearl powder group and the blank control group (both P<0.05). CONCLUSIONS: Nano-pearl powder and its bone substitute can promote the repair of bone defect, and the nano-pearl powder which contains rhBMP-2 has better osteogenic and repairing effect on defect.


Assuntos
Substitutos Ósseos , Animais , Proteína Morfogenética Óssea 2 , Colágeno , Fêmur , Humanos , Osteogênese , Pós , Coelhos , Proteínas Recombinantes , Fator de Crescimento Transformador beta
6.
J Biomed Nanotechnol ; 16(5): 672-688, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919487

RESUMO

The lack of neo-cartilage integration with host tissues is a great challenge for the clinical translation of new technologies for the repair of articular cartilage (AC) defect. Recently, we developed a promising double-layered collagen-based system for targeted delivery of fibroblast growth factor 2 (FGF2) to the subchondral bone for AC repair. The system effectively promoted the regeneration of both cartilage and subchondral bone. However, neo-cartilage integration was unsatisfactory, which might be due to the presence of a zone of cell death (ZCD) in the cartilage induced by injury. Here, we hypothesized that maintaining cell viability in the region surrounding the defect and decreasing the size of ZCD by using chondroprotective agents such as insulin-like growth factor-1 (IGF-1), might be an effective strategy to improve neo-cartilage integration. A targeted delivery system for IGF-1 to cartilage based on the FGF2 delivery system was formulated to weaken the impact on the effects of FGF2. The two growth factors were incorporated into the different layers of the membrane without interdiffusion. Due to the different densities of collagen fibers in the different layers, the in vitro and in vivo assays demonstrated that both proteins were released via unidirectional diffusion without mixing or lateral diffusion. Particularly, the released IGF-1 increased the viability of chondrocytes, decreased the ZCD size, and enhanced the integration of regenerative neo-cartilage with host tissues, without any undesirable effects on the FGF2mediated regeneration of cartilage and subchondral bone. Taken together, our findings demonstrate that the collagen fiber membrane-aided chondroprotective-based strategy is an effective way to improve neo-cartilage integration.


Assuntos
Cartilagem Articular , Osso e Ossos , Condrócitos , Colágeno , Matriz Extracelular
7.
PLoS One ; 15(8): e0234672, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764753

RESUMO

Opticin is a class III member of the extracellular matrix small leucine-rich repeat protein/proteoglycan (SLRP) family found in vitreous humour and cartilage. It was first identified associated with the surface of vitreous collagen fibrils and several other SLRPs are also known to bind collagen fibrils and it some cases alter fibril morphology. The purpose of this study was to investigate the binding of opticin to the collagen II-containing fibrils found in vitreous and cartilage. Electron microscopic studies using gold labelling demonstrated that opticin binds vitreous and thin cartilage collagen fibrils specifically at a single site in the gap region of the collagen D-period corresponding to the e2 stain band; this is the first demonstration of the binding site of a class III SLRP on collagen fibrils. Opticin did not bind thick cartilage collagen fibrils from cartilage or tactoids formed in vitro from collagen II, but shows high specificity for thin, heterotypic collagen fibrils containing collagens II, and XI or V/XI. Vitreous collagen fibrils from opticin null and wild-type mice were compared and no difference in fibril morphology or diameter was observed. Similarly, in vitro fibrillogenesis experiments showed that opticin did not affect fibril formation. We propose that when opticin is bound to collagen fibrils, rather than influencing their morphology it instead hinders the binding of other molecules to the fibril surfaces and/or act as an intermediary bridge linking the collagen fibrils to other non-collagenous molecules.


Assuntos
Colágeno/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteoglicanas/metabolismo , Animais , Sítios de Ligação , Bovinos , Colágeno/química , Colágeno/ultraestrutura , Proteínas da Matriz Extracelular/química , Proteínas da Matriz Extracelular/deficiência , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Microscopia Imunoeletrônica , Ligação Proteica , Proteoglicanas/química , Proteoglicanas/deficiência , Corpo Vítreo/química , Corpo Vítreo/metabolismo , Corpo Vítreo/ultraestrutura
8.
BMC Infect Dis ; 20(1): 580, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32762658

RESUMO

BACKGROUND: Dengue virus (DENV) causes the hospitalisation of an estimated 500,000 people every year. Outbreaks can severely stress healthcare systems, especially in rural settings. It is difficult to discriminate patients who need to be hospitalized from those that do not. Earlier work identified thrombocyte count and subsequent function as a promising prognostic marker of DENV severity. Herein, we investigated the potential of quantitative thrombocyte function tests in those admitted in the very early phase of acute DENV infections, using Multiplate™ multiple-electrode aggregometry to explore its potential in triage. METHODS: In this prospective cohort study all patients aged ≥13 admitted to Universitas Airlangga Hospital in Surabaya, Indonesia with a fever (≥38 °C) between 25 January and 1 August 2018 and with a clinical suspicion of DENV, were eligible for inclusion. Exclusion criteria were a thrombocyte count below 100 × 109/L and the use of any medication with a known anticoagulant effect, nonsteroidal anti-inflammatory drugs and acetyl salicylic acid. Clinical data was collected and blood was taken on admission, day 1 and day 7. Samples were tested for acute DENV, using Panbio NS1 ELISA. Platelet aggregation using ADP-, TRAP- and COL-test were presented as Area Under the aggregation Curve (AUC). Significance was tested between DENV+, probably DENV, fever of another origin, and healthy controls (HC). RESULTS: A total of 59 patients (DENV+ n = 10, DENV probable n = 25, fever other origin n = 24) and 20 HC were included. We found a significantly lower thrombocyte aggregation in the DENV+ group, compared with both HCs and the fever of another origin group (p < .001). Low ADP AUC values on baseline correlated to a longer hospital stay in DENV+ and probable DENV cases. CONCLUSION: Thrombocyte aggregation induced by Adenosine diphosphate, Collagen and Thrombin receptor activating peptide-6 is impaired in human DENV cases, compared with healthy controls and other causes of fever. This explorative study provides insights to thrombocyte function in DENV patients and could potentially serve as a future marker in DENV disease.


Assuntos
Plaquetas/metabolismo , Vírus da Dengue/imunologia , Dengue/diagnóstico , Dengue/epidemiologia , Sistemas Automatizados de Assistência Junto ao Leito , Testes Imediatos , Difosfato de Adenosina/sangue , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Colágeno/metabolismo , Dengue/virologia , Ensaio de Imunoadsorção Enzimática , Feminino , Febre/diagnóstico , Humanos , Indonésia/epidemiologia , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Agregação Plaquetária , Contagem de Plaquetas , Estudos Prospectivos , Índice de Gravidade de Doença , Adulto Jovem
9.
Clin Oral Investig ; 24(10): 3363-3394, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32827278

RESUMO

BACKGROUND: Collagen scaffolds are widely used for guided bone or tissue regeneration. Aiming to enhance their regenerative properties, studies have loaded various substances onto these scaffolds. This review aims to provide an overview of existing literature which conducted in vitro, in vivo, and clinical testing of drug-loaded collagen scaffolds and analyze their outcome of promoting oral regeneration. MATERIALS AND METHODS: PubMed, Scopus, and Ovid Medline® were systematically searched for publications from 2005 to 2019. Journal articles assessing the effect of substances on oral hard or soft tissue regeneration, while using collagen carriers, were screened and qualitatively analyzed. Studies were grouped according to their used substance type-biological medical products, pharmaceuticals, and tissue-, cell-, and matrix-derived products. RESULTS: A total of 77 publications, applying 36 different substances, were included. Collagen scaffolds were demonstrating favorable adsorption behavior and release kinetics which could even be modified. BMP-2 was investigated most frequently, showing positive effects on oral tissue regeneration. BMP-9 showed comparable results at lower concentrations. Also, FGF2 enhanced bone and periodontal healing. Antibiotics improved the scaffold's anti-microbial activity and reduced the penetrability for bacteria. CONCLUSION: Growth factors showed promising results for oral tissue regeneration, while other substances were investigated less frequently. Found effects of investigated substances as well as adsorption and release properties of collagen scaffolds should be considered for further investigation. CLINICAL RELEVANCE: Collagen scaffolds are reliable carriers for any of the applied substances. BMP-2, BMP-9, and FGF2 showed enhanced bone and periodontal healing. Antibiotics improved anti-microbial properties of the scaffolds.


Assuntos
Cicatrização , Proteína Morfogenética Óssea 2 , Osso e Ossos , Colágeno , Cinética , Tecidos Suporte
10.
Sci Total Environ ; 744: 140907, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-32763135

RESUMO

The so-called sea spray effect influences animals and humans living in coastal regions. As a consequence, δ13Ccarbonate, δ18Ocarbonate, δ18Ophosphate, and δ34Scollagen isotope values of affected individuals are more positive than otherwise expected. However, the effect is hidden in the case of humans who actually might have consumed marine food what would (partly) explain their isotopic signature. In order to correct for the sea spray effect in humans the dietary proportions were calculated based on the δ13Ccollagen and δ15Ncollagen isotope values using stable isotope mixing models. Four different programs (SISUS, simmr, IsotopeR, MixSIAR) were applied which resulted in quite different calculated diets. Each individual human can be corrected for the sea spray effect using the calculated proportion of terrestrial food (e.g. domesticated mammals, plants) and the approximated sea spray effect for each isotopic system. The differences in the calculated food proportions detected for the different mixing model programs, however, lead to differences in the correction procedure. We suggest using the dietary proportions as obtained by probabilistic SISUS rather than those of the Bayesian programs (simmr, IsotopeR, MixSIAR). The correction against the sea spray effect using the dietary proportions calculated by SISUS was supported by Gaussian Mixture Model (GMM) clustering which also enables the identification of probably non-local individuals in the dataset.


Assuntos
Colágeno , Fosfatos , Animais , Teorema de Bayes , Isótopos de Carbono , Carbonatos , Dieta , Humanos , Isótopos de Nitrogênio
11.
Int J Nanomedicine ; 15: 4991-5004, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764931

RESUMO

Introduction: Various materials and approaches have been used to reduce the mesh-induced inflammatory response and modify the mesh with tissue-matched mechanical properties, aiming to improve the repair of abdominal wall defects. Materials and Methods: In this study, we fabricated a polycaprolactone (PCL)/silk fibroin (SF) mesh integrated with amoxicillin (AMX)-incorporating multiwalled carbon nanotubes (MWCNTs) via electrospinning, grafting and crosslinking, developing a sustainable antibiotic and flexible mesh. AMX was loaded into the hollow tubular MWCNTs by physical adsorption, and a nanofibrous structure was constructed by electrospinning PCL and SF (40:60 w/w). The AMX@MWCNTs were then chemically grafted onto the surfaces of the PCL/SF nanofibers by treating with 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) solution for simultaneous crosslinking and coating. The incorporation of AMX into the MWCNTs (AMX@MWCNTs) and the integration of the AMX@MWCNTs with the PCL/SF nanofibers were characterized. Then, the functional mesh was fabricated and fully evaluated in terms of antibacterial activity, mechanical properties and host response. Results: Our results demonstrated that the PCL/SF nanofibrous structure was fabricated successfully by electrospinning. After integrating with AMX@MWCNT by grafting and crosslinking, the functional mesh showed undeformed structure, modified surface hydrophilicity and biocompatible interfaces, abdominal wall-matched mechanical properties, and a sustained-release antibiotic profile in E. coli growth inhibition compared to those of PCL/SF mesh in vitro. In a rat model with subcutaneous implantation, the functional mesh incited less mesh-induced inflammatory and foreign body responses than PCL/SF mesh within 14 days. The histological analysis revealed less infiltration of granulocytes and macrophages during this period, resulting in the loosely packed collagen deposition on the functional mesh and prominent collagen incorporation. Discussion: Therefore, this designed PCL/SF-AMX@MWCNT nanofibrous mesh, functionalized with antibacterial and tissue-matched mechanical properties, provides a promising alternative for the repair of abdominal wall defects.


Assuntos
Amoxicilina/química , Antibacterianos/química , Nanofibras/química , Nanotecnologia/métodos , Telas Cirúrgicas , Amoxicilina/farmacocinética , Amoxicilina/farmacologia , Animais , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Colágeno/química , Colágeno/metabolismo , Reagentes para Ligações Cruzadas/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fibroínas/química , Inflamação/etiologia , Masculino , Teste de Materiais , Camundongos , Nanotubos de Carbono/química , Poliésteres/química , Ratos Sprague-Dawley , Telas Cirúrgicas/efeitos adversos
12.
PLoS One ; 15(8): e0236516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32776970

RESUMO

Breast cancer is the most common cause of cancer-related deaths in women worldwide. Identification of reliable prognostic indicators and therapeutic targets is critical for improving patient outcome. Cancer in companion animals often strongly resembles human cancers and a comparative approach to identify prognostic markers can improve clinical care across species. Feline mammary tumors (FMT) serve as models for extremely aggressive triple negative breast cancer (TNBC) in humans, with high rates of local and distant recurrence after resection. Despite the aggressive clinical behavior of most FMT, current prognostic indicators are insufficient for accurately predicting outcome, similar to human patients. Given significant heterogeneity of mammary tumors, there has been a recent focus on identification of universal tumor-permissive stromal features that can predict biologic behavior and provide therapeutic targets to improve outcome. As in human and canine patients, collagen signatures appear to play a key role in directing mammary tumor behavior in feline patients. We find that patients bearing FMTs with denser collagen, as well as longer, thicker and straighter fibers and less identifiable tumor-stromal boundaries had poorer outcomes, independent of the clinical variables grade and surgical margins. Most importantly, including the collagen parameters increased the predictive power of the clinical model. Thus, our data suggest that similarities with respect to the stromal microenvironment between species may allow this model to predict outcome and develop novel therapeutic targets within the tumor stroma that would benefit both veterinary and human patients with aggressive mammary tumors.


Assuntos
Colágeno/metabolismo , Neoplasias Mamárias Animais/cirurgia , Prognóstico , Neoplasias de Mama Triplo Negativas/cirurgia , Animais , Gatos , Colágeno/genética , Modelos Animais de Doenças , Feminino , Humanos , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Glândulas Mamárias Animais/cirurgia , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Microambiente Tumoral/genética
14.
Int J Nanomedicine ; 15: 4943-4956, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764927

RESUMO

Background: Hydroxyapatite (HA) [Ca5(PO4)3(OH)] is a naturally occurring calcium phosphate which makes up 60-70% of the dry weight of human bones. Nano-scale HA particles are increasingly being used as carriers for controlled and targeted delivery of bioactive agents like drugs, proteins, and nucleic acids due to their high porosity, negative charge, and biodegradability. Purpose: Although much effort has been devoted to understanding the delivery kinetics and effects of the payloads in such carriers, a thorough understanding of the influence of the carriers themselves is lacking. Methods: HA particles (300 µg/mL) were administered to primary human dermal fibroblasts (HDFs). The uptake and intracellular localization of the particles were determined by flow cytometry, confocal imaging, and transmission electron microscopy (TEM). Immunological assays and PCR were performed to determine the levels of pro-inflammatory cytokines and collagens in cell lysates and media supernatant. Results: The current study explores the effects of poly-dispersed HA particles on primary HDFs as a model system. The majority of the particles were determined to range between 150 and 200 nm in diameter. Upon exposure to HA suspensions, primary HDFs internalized the particles by endocytosis within 6 hours of exposure, showing maximum uptake at 72 hours following which the particles were exocytosed by 168 hours. This correlated to reduced secretion of various pro-inflammatory and pro-collagenic cytokines. Biochemical analysis further revealed a reduction in Type I collagen expression and secretion. Conclusion: HA particles have an immune-modulatory effect on dermal fibroblasts and reduce collagen production, which may impact the integrity of the extracellular matrix (ECM). This study demonstrates the need to consider the secondary effects of particulate carriers like HA, beyond basic cytotoxicity, in the specific tissue environment where the intended function is to be realized.


Assuntos
Colágeno/metabolismo , Durapatita/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Pele/citologia , Colágeno Tipo I/metabolismo , Citocinas/metabolismo , Durapatita/química , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Humanos
15.
Bone Joint J ; 102-B(8): 1095-1106, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32731821

RESUMO

AIMS: Achilles tendon injuries are a frequent problem in orthopaedic surgery due to their limited healing capacity and the controversy surrounding surgical treatment. In recent years, tissue engineering research has focused on the development of biomaterials to improve this healing process. The aim of this study was to analyze the effect of tendon augmentation with a nanostructured fibrin-agarose hydrogel (NFAH) or genipin cross-linked nanostructured fibrin-agarose hydrogel (GP-NFAH), on the healing process of the Achilles tendon in rats. METHODS: NFAH, GP-NFAH, and MatriDerm (control) scaffolds were generated (five in each group). A biomechanical and cell-biomaterial-interaction characterization of these biomaterials was then performed: Live/Dead Cell Viability Assay, water-soluble tetrazolium salt-1 (WST-1) assay, and DNA-released after 48 hours. Additionally, a complete section of the left Achilles tendon was made in 24 Wistar rats. Animals were separated into four treatment groups (six in each group): direct repair (Control), tendon repair with MatriDerm, or NFAH, or GP-NFAH. Animals were euthanized for further histological analyses after four or eight weeks post-surgery. The Achilles tendons were harvested and a histopathological analysis was performed. RESULTS: Tensile test revealed that NFAH and GP-NFAH had significantly higher overall biomechanical properties compared with MatriDerm. Moreover, biological studies confirmed a high cell viability in all biomaterials, especially in NFAH. In addition, in vivo evaluation of repaired tendons using biomaterials (NFAH, GP-NFAH, and MatriDerm) resulted in better organization of the collagen fibres and cell alignment without clinical complications than direct repair, with a better histological score in GP-NFAH. CONCLUSION: In this animal model we demonstrated that NFAH and GP-NFAH had the potential to improve tendon healing following a surgical repair. However, future studies are needed to determine the clinical usefulness of these engineered strategies. Cite this article: Bone Joint J 2020;102-B(8):1095-1106.


Assuntos
Tendão do Calcâneo/cirurgia , Microambiente Celular/efeitos dos fármacos , Colágeno/uso terapêutico , Elastina/uso terapêutico , Regeneração/efeitos dos fármacos , Traumatismos dos Tendões/cirurgia , Tendão do Calcâneo/lesões , Animais , Materiais Biocompatíveis/farmacologia , Modelos Animais de Doenças , Fibrina/farmacologia , Hidrogéis/farmacologia , Masculino , Nanoestruturas , Distribuição Aleatória , Ratos , Ratos Wistar , Tendões/fisiologia , Engenharia Tecidual/métodos , Cicatrização/efeitos dos fármacos , Cicatrização/fisiologia
16.
Adv Exp Med Biol ; 1265: 187-199, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32761577

RESUMO

Amino acids are the building blocks of all proteins, including the most abundant fibrous proteins in the skin, as keratins, collagen and elastin. Sagging and wrinkled skin are features of chronic sun-damaged and aged uncared skin, and they are mainly associated with the deterioration of collagen and elastic fibers. The maintenance of skin structures by self-repair processes is essential to skin health. Thus, amino acids significantly impact the appearance of the skin. Amino acids are important nutrients required for (a) wound healing promotion and repair of the damaged skin; (b) acid-base balance and water retention in cellular layers, such as stratum corneum; (c) protection against sunlight damage; (d) maintenance of an appropriate skin microbiome. This review highlights the contribution of all proteinogenic amino acids and some related metabolites to the skin structures as constituents of the main cutaneous proteins or as signaling molecules for the regulation and determination of skin physiology.


Assuntos
Aminoácidos/metabolismo , Pele/metabolismo , Colágeno , Elastina , Humanos , Queratinas , Pele/citologia , Pele/microbiologia , Envelhecimento da Pele
17.
Gene ; 761: 145024, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32755659

RESUMO

Understanding how various pathologies of breast cancer respond to their environment may be imperative in the creation of novel therapeutic targets. Central to the organisation and behaviour of cells within the tumour microenvironment is the extracellular matrix (ECM), a meshwork of fibrous proteins and glycoproteins that directly influences cell behaviour and the bioavailability of signalling molecules. Our appreciation on how the composition of the ECM can influence cancer behaviour has evolved significantly and although we are highly cognisant of the dramatic impact the ECM can have on cancer cell behaviour, we continue to neglect this during diagnosis and treatment. In the following study, we aimed to identify how three breast cancer cell lines respond functionally and genetically to common components of the ECM. Using real time and end point assays we have identified similar patterns of behaviour among the three breast cancer cell lines in response to commonly found ECM components of the breast. Using a selected gene panel, we have been able to identify cell line specific changes in gene differentiation when breast cancer cells are in contact with these elements. Although the response of our cells to these elements differ at the genetic level, their functional responses are consistent. This work adds to the growing arguments that highlight a need for histologically assessing ECM composition of breast tumours. In particular monitoring of fibrous protein deposition at the site of malignancy could provide critical information during clinical assessment influencing disease prognosis and treatment decisions for breast cancer patients.


Assuntos
Neoplasias da Mama/genética , Colágeno/genética , Fibronectinas/genética , Mama/patologia , Linhagem Celular Tumoral , Colágeno/metabolismo , Colágeno Tipo I/genética , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/genética , Feminino , Fibronectinas/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Genótipo , Glicoproteínas/genética , Humanos , Fenótipo , Prognóstico , Transdução de Sinais , Microambiente Tumoral
18.
Clin Oral Implants Res ; 31(10): 1010-1024, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32799365

RESUMO

OBJECTIVES: The objective of this randomized controlled trial was to compare alveolar ridge preservation using a bone substitute material and covered with a synthetic or porcine collagen membrane. MATERIALS AND METHODS: Thirty-two sockets in the aesthetic maxillary region of 30 patients were randomized into two groups. Randomization was stratified according to bone wall defect. Flapless technique was used, and sockets were grafted with bi-phasic calcium phosphate particulate bone substitute and covered by synthetic polyethylene glycol (PEG; test group) or porcine-derived collagen membrane (CM; control group). No primary closure was attempted. A cone beam computed tomography (CBCT) scan was performed immediately after the surgical procedure and repeated 22 weeks later. OnDemand3D was used to superimpose scan images and assess changes. The mean vertical and horizontal percentage bone loss were calculated and implants placed after 6 months with or without additional augmentation. RESULTS: There were no baseline differences between groups or dropouts. The mean percentage loss at the labial plate and at the coronal part of the sockets was statistically significantly lower in the test group compared with controls (-2.86% [SD = 13.48] versus 7.42% [SD = 11.95]; 13.45% [SD = 11.97] versus 28.59% [SD = 16.97]). Implants were placed after 6 months, and there was no difference in need for further augmentation between PEG (n = 5) or CM (n = 4). CONCLUSION: Sites treated with PEG membrane showed less percentage loss in horizontal and vertical measurements in this trial.


Assuntos
Perda do Osso Alveolar , Aumento do Rebordo Alveolar , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/prevenção & controle , Perda do Osso Alveolar/cirurgia , Animais , Colágeno , Tomografia Computadorizada de Feixe Cônico , Estética Dentária , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Suínos , Extração Dentária , Alvéolo Dental/diagnóstico por imagem , Alvéolo Dental/cirurgia
19.
PLoS One ; 15(8): e0237231, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853250

RESUMO

In this study, we examined the effect of differing gap lengths on regeneration of transected recurrent laryngeal nerves using silicon tubes containing type I collagen gel and the ability of this regeneration to result in restoration of vocal fold movements in rats. We simulated nerve gaps in Sprague-Dawley rats by transecting the left recurrent laryngeal nerves and bridged the nerve stumps using silicon tubes containing type 1 collagen gel. Three experimental groups, in which the gap lengths between the stumps were 1, 3, or 5 mm, were compared with a control group in which the nerve was transected but was not bridged. After surgery, we observed vocal fold movements over time with a laryngoscope. At week 15, we assessed the extent of nerve regeneration in the tube, histologically and electrophysiologically. We also assessed the degree of atrophy of the thyroarytenoid muscle (T/U ratio). Restoration of vocal fold movements was observed in 9 rats in the 1-mm group, in 6 rats in the 3-mm group, and in 3 rats in the 5-mm group. However, in most rats, restoration was temporary, with only one rat demonstrating continued vocal fold movements at week 15. In electromyograph, evoked potentials were observed in rats in the 1-mm and 3-mm groups. Regenerated tissue in the tube was thickest in the 1-mm group, followed by the 3-mm and 5-mm groups. The regenerated tissue showed the presence of myelinated and unmyelinated nerve fibers. In assessment of thyroarytenoid muscle atrophy, the T/U ratio was highest in the 1-mm group, followed by the 3-mm and 5-mm groups. We successfully regenerated the nerves and produced a rat model of recurrent laryngeal nerve regeneration that demonstrated temporary recovery of vocal fold movements. This rat model could be useful for assessing novel treatments developing in the future.


Assuntos
Colágeno/uso terapêutico , Regeneração Nervosa , Traumatismos do Nervo Laríngeo Recorrente/terapia , Nervo Laríngeo Recorrente/fisiopatologia , Animais , Materiais Biocompatíveis/química , Colágeno/administração & dosagem , Modelos Animais de Doenças , Géis/administração & dosagem , Géis/uso terapêutico , Masculino , Regeneração Nervosa/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Nervo Laríngeo Recorrente/fisiologia , Traumatismos do Nervo Laríngeo Recorrente/fisiopatologia , Silício/química
20.
PLoS One ; 15(8): e0237116, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857787

RESUMO

Bone metastases are a frequent complication in prostate cancer, and several studies have shown that vitamin D deficiency promotes bone metastases. However, while many studies focus on vitamin D's role in cell metabolism, the effect of chronically low vitamin D levels on bone tissue, i.e. insufficient mineralization of the tissue, has largely been ignored. To investigate, whether poor tissue mineralization promotes cancer cell attachment, we used a fluorescence based adhesion assay and single cell force spectroscopy to quantify the adhesion of two prostate cancer cell lines to well-mineralized and demineralized dentin, serving as biomimetic bone model system. Adhesion rates of bone metastases-derived PC3 cells increased significantly on demineralized dentin. Additionally, on mineralized dentin, PC3 cells adhered mainly via membrane anchored surface receptors, while on demineralized dentin, they adhered via cytoskeleton-anchored transmembrane receptors, pointing to an interaction via exposed collagen fibrils. The adhesion rate of lymph node derived LNCaP cells on the other hand is significantly lower than that of PC3 and not predominately mediated by cytoskeleton-linked receptors. This indicates that poor tissue mineralization facilitates the adhesion of invasive cancer cells by the exposure of collagen and emphasizes the disease modifying effect of sufficient vitamin D for cancer patients.


Assuntos
Calcificação Fisiológica , Adesão Celular , Neoplasias da Próstata/metabolismo , Animais , Materiais Biomiméticos/química , Linhagem Celular Tumoral , Colágeno/metabolismo , Citoesqueleto/metabolismo , Dentina/química , Elefantes , Humanos , Masculino , Receptores de Superfície Celular/metabolismo , Tecidos Suporte/química , Vitamina D/metabolismo
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