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1.
Acta Cir Bras ; 35(3): e202000303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32490900

RESUMO

PURPOSE: To evaluate the in vivo response of photobiomodulation therapy associated with norbixin-based poly(hydroxybutyrate) membrane (PHB) in tenotomized calcaneal tendon. METHODS: Thirty rats were randomly allocated to six groups (n=5 each): LED groups (L1, L2 and L3) and membrane + LED groups (ML1, ML2 and ML3). The right calcaneal tendons of all animals were sectioned transversely and were irradiated with LED daily, one hour after surgery every 24 hours, until the day of euthanasia. At the end of the experiments the tendons were removed for histological analysis. RESULTS: The histological analysis showed a significant reduction in inflammatory cells in the ML1, ML2 and ML3 groups (p=0.0056, p=0.0018 and p<0.0001, respectively) compared to those in the LED group. There was greater proliferation of fibroblasts in the ML1 (p<0.0001) and L3 (p<0.0001) groups. A higher concentration of type I collagen was also observed in the ML1 group (p=0.0043) replacing type III collagen. CONCLUSION: Photobiomodulation in association with norbixin-based PHB membrane led to control of the inflammatory process. However, it did not favor fibroblast proliferation and did not optimize type I collagen formation in the expected stage of the repair process.


Assuntos
Tendão do Calcâneo/efeitos da radiação , Carotenoides/farmacologia , Hidroxibutiratos/farmacologia , Terapia com Luz de Baixa Intensidade/métodos , Tendinopatia/radioterapia , Tenotomia/métodos , Tendão do Calcâneo/efeitos dos fármacos , Tendão do Calcâneo/cirurgia , Animais , Colágeno/farmacologia , Colágeno Tipo I/análise , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo III/análise , Colágeno Tipo III/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Fibroblastos/química , Fibroblastos/efeitos dos fármacos , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Cicatrização/efeitos dos fármacos , Cicatrização/efeitos da radiação
2.
Circ Arrhythm Electrophysiol ; 13(7): e007588, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32538131

RESUMO

BACKGROUND: Scientific research on atrial fibrosis in atrial fibrillation (AF) has mainly focused on quantitative or molecular features. The purpose of this study was to perform a clinicoarchitectural/structural investigation of fibrosis to provide one key to understanding the electrophysiological/clinical aspects of AF. METHODS: We characterized the fibrosis (amount, architecture, cellular components, and ultrastructure) in left atrial biopsies from 121 patients with persistent/long-lasting persistent AF (group 1; 59 males; 60±11 years; 91 mitral disease-related AF, 30 nonmitral disease-related AF) and from 39 patients in sinus rhythm with mitral valve regurgitation (group 2; 32 males; 59±12 years). Ten autopsy hearts served as controls. RESULTS: Qualitatively, the fibrosis exhibited the same characteristics in all cases and displayed particular architectural scenarios (which we arbitrarily subdivided into 4 stages) ranging from isolated foci to confluent sclerotic areas. The percentage of fibrosis was larger and at a more advanced stage in group 1 versus group 2 and, within group 1, in patients with rheumatic disease versus nonrheumatic cases. In patients with AF with mitral disease and no rheumatic disease, the percentage of fibrosis and the fibrosis stages correlated with both left atrial volume index and AF duration. The fibrotic areas mainly consisted of type I collagen with only a minor cellular component (especially fibroblasts/myofibroblasts; average value range 69-150 cells/mm2, depending on the areas in AF biopsies). A few fibrocytes-circulating and bone marrow-derived mesenchymal cells-were also detectable. The fibrosis-entrapped cardiomyocytes showed sarcolemmal damage and connexin 43 redistribution/internalization. CONCLUSIONS: Atrial fibrosis is an evolving and inhomogeneous histological/architectural change that progresses through different stages ranging from isolated foci to confluent sclerotic zones which-seemingly-constrain impulse conduction across restricted regions of electrotonically coupled cardiomyocytes. The fibrotic areas mainly consist of type I collagen extracellular matrix and, only to a lesser extent, mesenchymal cells.


Assuntos
Fibrilação Atrial/patologia , Átrios do Coração/patologia , Doenças das Valvas Cardíacas/patologia , Miocárdio/patologia , Cardiopatia Reumática/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/metabolismo , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/terapia , Função do Átrio Esquerdo , Remodelamento Atrial , Biópsia , Colágeno Tipo I/análise , Conexina 43/análise , Feminino , Fibrose , Átrios do Coração/química , Átrios do Coração/fisiopatologia , Doenças das Valvas Cardíacas/metabolismo , Doenças das Valvas Cardíacas/fisiopatologia , Doenças das Valvas Cardíacas/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/química , Estudos Retrospectivos , Cardiopatia Reumática/metabolismo , Cardiopatia Reumática/fisiopatologia , Cardiopatia Reumática/terapia
3.
Braz Oral Res ; 34: e014, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32074214

RESUMO

Although dental implants and bone regenerative procedures are important approaches for the reestablishment of esthetics and function in young patients with a history of generalized aggressive periodontitis (GAP), no predictable outcomes have been reported, and the host osteo-immunoinflammatory response may play a relevant role in this context. In view of the lack of molecular investigations into the bone tissue condition of young patients with periodontitis, the aim of this study was to evaluate the gene expression of bone-related factors in this population. Bone biopsies were obtained from the posterior mandible in 16 individuals previously diagnosed with GAP and on periodontal support therapy and from 17 periodontally healthy (PH) patients. The gene expression of tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-ß, receptor activator of the NF-κB ligand (RANKL), osteoprotegerin (OPG), osteocalcin (OC), bone sialoprotein (BSP), and type I collagen (COL-I), important biomarkers of bone turnover, was evaluated by qRT-PCR. Lower TGF-ß and OPG mRNA levels were observed in GAP patients compared to PH individuals (p ≤ 0.05). There were no between-group differences in levels of TNF-α, BSP, RANKL, OC, or COL-I mRNA (p>0.05). In young adults, a history of periodontal disease can negatively modulate the gene expression of important bone-related factors in alveolar bone tissue. These molecular outcomes may contribute to the future development of therapeutic approaches to benefit bone healing in young patients with history of periodontitis via modulation of osteo-immuno-inflammatory biomarkers.


Assuntos
Periodontite Agressiva/genética , Expressão Gênica , Adulto , Periodontite Agressiva/metabolismo , Processo Alveolar/química , Biomarcadores , Colágeno Tipo I/análise , Colágeno Tipo I/genética , Estudos Transversais , Feminino , Humanos , Sialoproteína de Ligação à Integrina/análise , Sialoproteína de Ligação à Integrina/genética , Masculino , Osteocalcina/análise , Osteocalcina/genética , Osteoprotegerina/análise , Osteoprotegerina/genética , Ligante RANK/análise , Ligante RANK/genética , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência , Método Simples-Cego , Estatísticas não Paramétricas , Fator de Crescimento Transformador beta/análise , Fator de Crescimento Transformador beta/genética , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/genética , Adulto Jovem
4.
Acta Cir Bras ; 34(11): e201901101, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939594

RESUMO

PURPOSE: To determine the efficacy of norbixin-based poly(hydroxybutyrate) (PHB) membranes for Achilles tendon repair. METHODS: Thirty rats were submitted to total tenotomy surgery of the right Achilles tendon and divided into two groups (control and membrane; n = 15 each), which were further subdivided into three subgroups (days 7, 14, and 21; n = 5 each). Samples were analyzed histologically. RESULTS: Histological analysis showed a significant reduction in inflammatory infiltrates on days 7, 14 (p < 0.0001 for both), and 21 (p = 0.0004) in the membrane group compared to that in the control group. There was also a significant decrease in the number of fibroblasts in the control group on days 7, 14 (p < 0.0001), and 21 (p = 0.0032). Further, an increase in type I collagen deposition was observed in the membrane group compared to that in the control group on days 7 (p = 0.0133) and 14 (p = 0.0107). CONCLUSION: Treatment with norbixin-based PHB membranes reduces the inflammatory response, increases fibroblast proliferation, and improves collagen production in the tendon repair region, especially between days 7 and 14.


Assuntos
Tendão do Calcâneo/efeitos dos fármacos , Tendão do Calcâneo/cirurgia , Carotenoides/farmacologia , Hidroxibutiratos/farmacologia , Poliésteres/farmacologia , Tenotomia/métodos , Tendão do Calcâneo/patologia , Animais , Colágeno Tipo I/análise , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo III/análise , Colágeno Tipo III/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Humanos , Masculino , Ratos Wistar , Valores de Referência , Regeneração/efeitos dos fármacos , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
5.
BMC Gastroenterol ; 19(1): 228, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31883514

RESUMO

BACKGROUND: Compounds in clinical development for nonalcoholic steatohepatitis (NASH) improve liver histopathology in diet-induced obese mouse models of biopsy-confirmed NASH. Since the biopsy section used for histopathological evaluation represents only < 1% of the whole mouse liver, we evaluated how well biopsy-based quantitative image analyses correlate to stereology-based whole-liver quantitative changes upon drug treatment. METHODS: Male leptin-deficient Lepob/Lepob mice were fed the Amylin liver NASH (AMLN) diet for 16 weeks before stratification into treatment groups using a biopsy-based evaluation of type I collagen αI (col1a1) levels. Mice were treated for 8 weeks with either vehicle (PO, QD), liraglutide (0.4 mg/kg, SC, QD), elafibranor (30 mg/kg, PO, QD) or INT-767 (10 mg/kg, PO, QD). Terminal quantitative histological assessment of liver lipid (hematoxylin-eosin staining), inflammation (galectin-3 immunohistochemistry (IHC); gal-3), and fibrosis (col1a1 IHC) was performed on terminal liver biopsies and compared with stereologically sampled serial sections spanning the medial, left and right lateral lobe of the liver. RESULTS: The distribution of liver lipid and fibrosis was markedly consistent across lobes, whereas inflammation showed some variability. While INT-767 and liraglutide significantly reduced total liver weight by 20 and 48%, respectively, elafibranor tended to exacerbate hepatomegaly in Lepob/Lepob-NASH mice. All three compounds markedly reduced biopsy-based relative liver lipid content. Elafibranor and INT-767 significantly reduced biopsy-based relative gal-3 levels (P < 0.001), whereas INT-767 and liraglutide tended to reduce relative col1a1 levels. When changes in liver weight was accounted for, both INT-767 and liraglutide significantly reduced biopsy-based total col1a1 content. Although minor differences in absolute and relative liver lipid, inflammation and fibrosis levels were observed across lobes, the interpretation of drug-induced effects were consistent with biopsy-based conclusions. Notably, the incorporation of changes in total liver mass revealed that liraglutide's efficacy reached statistical significances for all analyzed parameters. CONCLUSIONS: In conclusion, in-depth analyses of liver homogeneity demonstrated that drug-induced improvement in liver biopsy-assessed histopathology is representative for overall liver effects assessed using stereology. Importantly, these findings reveal how changes in whole-liver mass should be considered to provide a deeper understanding of apparent drug treatment efficacy in preclinical NASH studies.


Assuntos
Fígado/efeitos dos fármacos , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/complicações , Animais , Ácidos e Sais Biliares/uso terapêutico , Biópsia , Peso Corporal/efeitos dos fármacos , Chalconas/uso terapêutico , Colágeno Tipo I/análise , Dieta Hiperlipídica , Galectina 3/análise , Polipeptídeo Amiloide das Ilhotas Pancreáticas/administração & dosagem , Leptina/deficiência , Lipídeos/análise , Liraglutida/uso terapêutico , Fígado/química , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Obesos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Tamanho do Órgão/efeitos dos fármacos , PPAR alfa/agonistas , PPAR delta/agonistas , Propionatos/uso terapêutico , Reprodutibilidade dos Testes
6.
Int J Mol Sci ; 21(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861912

RESUMO

The dermal-epidermal junction (DEJ) provides a physical and biological interface between the epidermis and the dermis. In addition to providing a structural integrity, the DEJ also acts as a passageway for molecular transport. Based on the recently reported importance of the DEJ in skin aging, novel peptide derivatives have been tested for their effects on basement membrane (BM) protein expressions in cultured human epidermal keratinocytes. As a result, protein expressions of collagen XVII, laminin and nidogen were stimulated by the test peptide and peptides complex. Further ex vivo evaluation using excised human skin, confirmed that the topical application of the peptides complex significantly increased dermal collagen expression, as well as expressions of collagen XVII and laminin. Interestingly, while the origin of the laminin protein is epidermal keratinocytes, the immunohistochemical staining of skin showed that laminin was only detected in the uppermost layer of the dermis, which suggests a tight assembly of laminin protein onto the dermal side of the DEJ. These results suggest that a peptide complex could improve the structural properties of the DEJ through its ability to stimulate BM proteins. In order to evaluate the anti-wrinkle benefits of the peptide complex in vivo, a clinical study was performed on 22 healthy Asian female volunteers older than 40 years. As a result, significant improvements in skin wrinkles for all of the five sites were observed after two weeks, as assessed by skin topographic measurements. Collectively, these results demonstrate the anti-aging efficacy of the peptides complex.


Assuntos
Membrana Basal/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Peptídeos/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Adulto , Autoantígenos/análise , Linhagem Celular , Colágeno Tipo I/análise , Feminino , Humanos , Queratinócitos/química , Queratinócitos/citologia , Laminina/análise , Pessoa de Meia-Idade , Colágenos não Fibrilares/análise , Pele/química , Pele/citologia
7.
Acta cir. bras ; 34(11): e201901101, Nov. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1054681

RESUMO

Abstract Purpose: To determine the efficacy of norbixin-based poly(hydroxybutyrate) (PHB) membranes for Achilles tendon repair. Methods: Thirty rats were submitted to total tenotomy surgery of the right Achilles tendon and divided into two groups (control and membrane; n = 15 each), which were further subdivided into three subgroups (days 7, 14, and 21; n = 5 each). Samples were analyzed histologically. Results: Histological analysis showed a significant reduction in inflammatory infiltrates on days 7, 14 (p < 0.0001 for both), and 21 (p = 0.0004) in the membrane group compared to that in the control group. There was also a significant decrease in the number of fibroblasts in the control group on days 7, 14 (p < 0.0001), and 21 (p = 0.0032). Further, an increase in type I collagen deposition was observed in the membrane group compared to that in the control group on days 7 (p = 0.0133) and 14 (p = 0.0107). Conclusion: Treatment with norbixin-based PHB membranes reduces the inflammatory response, increases fibroblast proliferation, and improves collagen production in the tendon repair region, especially between days 7 and 14.


Assuntos
Humanos , Animais , Masculino , Poliésteres/farmacologia , Tendão do Calcâneo/cirurgia , Tendão do Calcâneo/efeitos dos fármacos , Carotenoides/farmacologia , Tenotomia/métodos , Hidroxibutiratos/farmacologia , Valores de Referência , Regeneração/efeitos dos fármacos , Tendão do Calcâneo/patologia , Reprodutibilidade dos Testes , Ratos Wistar , Colágeno Tipo I/análise , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo III/análise , Colágeno Tipo III/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos
8.
Nano Lett ; 19(8): 5443-5451, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31369708

RESUMO

Most living tissues exhibit the specific stiffness, which has been known to have profound influence on cell behaviors, yet how the stiffness affects cellular responses to engineered nanomaterials has not been elucidated. Particularly, discrepancies exist between in vitro and in vivo nanotoxicological studies. Here, we investigated the effects of substrate stiffness on the fibrogenic responses of normal human lung fibroblasts (NHLFs) to multiwalled carbon nanotubes (MWCNTs). NHLFs were grown on polyacrylamide (PAAm) hydrogels with the stiffness comparable to that of human normal and fibrotic lung tissues, and treated with MWCNTs for various time. The fibrogenic responses, including cell proliferation, reactive oxygen species production, and collagen I expression, of NHLFs to MWCNTs were observed to be regulated by substrate stiffness in a time-dependent manner. NHLFs generally were rounded on soft hydrogels and required a long treatment time to exhibit fibrogenic responses, while on stiff hydrogels the cells were well-spread with defined stress fibers and short-time MWCNTs treatment sufficiently induced the fibrogenic responses. Mechanistic studies showed that MWCNTs induced fibrogenesis of NHLFs through promoting expression and phosphorylation of focal adhesion kinase (FAK), while attenuating intracellular tension in the cells on stiff gels could increase MWCNTs uptake and thus elevate the induced fibrogenic responses. Moreover, we proposed a time-stiffness superposition principle to describe the equivalent effects of treatment time and substrate stiffness on nanomaterials-induced fibrogenesis, which suggested that increasing substrate stiffness expedited fibrogenesis and shed light on the rational design of in vitro models for nanotoxicological study.


Assuntos
Colágeno Tipo I/metabolismo , Fibroblastos/metabolismo , Pulmão/citologia , Nanotubos de Carbono/efeitos adversos , Linhagem Celular , Movimento Celular , Colágeno Tipo I/análise , Elasticidade , Fibroblastos/patologia , Proteína-Tirosina Quinases de Adesão Focal/análise , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Humanos , Pulmão/metabolismo , Pulmão/patologia , Nanotubos de Carbono/química , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo
9.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(7): 871-876, 2019 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-31298006

RESUMO

Objective: To explore the effect of platelet-rich plasma (PRP) in treatment of Achilles tendinopathy in rabbits, and provide experimental evidence for the clinical application of PRP in treatment of Achilles tendinopathy. Methods: Forty-eight adult New Zealand white rabbits, weighing 2.5-3.0 kg, male or female, were randomly divided into model group (group A), model control group (group B), model+treatment control group (group C), model+treatment group (group D), with 12 in each group. The rabbits were injected with type Ⅰ collagenase to prepare Achilles tendinopathy models in groups A, C, and D, and with an equal dose of normal saline in group B. The blood from the central artery of rabbit ear was taken to preprare PRP by secondary centrifugation in group D. The results of platelet counts showed that PRP platelets reached 3 to 5 times the whole blood. After the model was prepared, the rabbits in groups C and D were injected with physiological saline and autologous PRP at the molding site respectively, once a week, 0.8 mL each time for 4 weeks. At 1 week after PRP injection, the relative hardness (expressed as HRD%) of Achilles tendon was evaluated by ultrasound elastic quantitative imaging detection technique; the maximum breaking load of Achilles tendon was measured by universal electronic tensile testing machine; the contents of collagen type Ⅰ and Ⅲ were determined by ELISA; and the morphology of Achilles tendon collagen fibers was observed by HE and Masson stainings. Results: All animals survived during the experiment. The results of ultrasound elastic quantitative imaging and mechanical tests showed that the HRD% and the maximum breaking load were significantly lower in group A than in group B ( P<0.05) and in group C than in group D ( P<0.05). The results of ELISA showed that the content of collagen type Ⅰ was significantly lower in group A than in group B ( P<0.05) and in group C than in group D ( P<0.05); the content of collagen type Ⅲ was significantly higher in group A than in group B ( P<0.05) and in group D than in group C ( P<0.05). HE and Masson stainings showed that the Achilles tendon collagen fibers were irregularly curled and the structure was severely damaged in group A; the fibers were parallel and ordered, and the structure was complete in group B; the fibers were irregularly curled and structurally disordered in group C; the fibers were slightly curled and the structure was relatively complete in group D. Conclusion: A rabbit model of Achilles tendinopathy can be reconstructed by type Ⅰ collagenase injection. PRP treatment can increase the Achilles tendon hardness and maximum breaking load, up-regulate the expression level of collagen type Ⅰ and Ⅲ, improve the structure of Achilles tendon collagen fiber, and promote the repair in rabbit Achilles tendinopathy model.


Assuntos
Tendão do Calcâneo , Plasma Rico em Plaquetas , Tendinopatia , Tendão do Calcâneo/patologia , Animais , Colágeno Tipo I/análise , Colágeno Tipo III/análise , Feminino , Masculino , Coelhos , Distribuição Aleatória , Tendinopatia/terapia
10.
Exp Physiol ; 104(10): 1562-1574, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31290182

RESUMO

NEW FINDINGS: What is the central question of this study? What are the effects of the antifibrotic peptide acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) on the angiotensin-converting enzyme 2 (ACE2)-angiotensin-(1-7)-Mas axis during the occurrence and progression of silicosis? What is the main finding and its importance? Ac-SDKP inhibited lung fibrosis in rats exposed to silica by activation of the ACE2-angiotensin-(1-7)-Mas axis. Angiotensin-(1-7) potentially promotes Ac-SDKP by increasing the level of meprin α, the major synthetase of Ac-SDKP. Thus, the interaction Ac-SDKP and angiotesin-(1-7) in silicosis could provide a new therapeutic strategy. ABSTRACT: The central role of angiotensin-converting enzyme (ACE) in the occurrence and progression of silicosis has been established. The antifibrotic peptide acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) can be degraded by ACE. The ACE2-angiotensin-(1-7)-Mas axis is protective and acts to counterbalance the detrimental effects of ACE-angiotensin II (Ang II)-Ang II type 1 receptor and exerts antifibrotic effects. Here, we demonstrate an interaction between Ac-SDKP and Ang-(1-7) in the inhibition of collagen deposition and myofibroblast differentiation in rats exposed to silica. Treatment with Ac-SDKP increased the level of ACE2-Ang-(1-7)-Mas in rats or in cultured fibroblasts and decreased the levels of collagen type I and α-smooth muscle actin. Furthermore, exogenous Ang-(1-7) had similar antifibrotic effects and increased the level of meprin α, a major Ac-SDKP synthetase, both in vivo and in vitro. Compared with non-silicotic patients exposed to silica, the level of serum ACE was increased in patients with silicosis phase III; the levels of Ang II and Ang-(1-7) were high in patients with silicosis phase II; and the level of Ac-SDKP was high in the silicosis phase III group. These data imply that Ac-SDKP and Ang-(1-7) have an interactive effect as regulatory peptides of the renin-angiotensin system and exert antifibrotic effects.


Assuntos
Angiotensina I/sangue , Oligopeptídeos/uso terapêutico , Fragmentos de Peptídeos/sangue , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Receptores Acoplados a Proteínas-G/efeitos dos fármacos , Silicose/tratamento farmacológico , Actinas/metabolismo , Angiotensina II/sangue , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/metabolismo , Colágeno Tipo I/análise , Colágeno Tipo I/metabolismo , Fibroblastos/efeitos dos fármacos , Humanos , Masculino , Peptidil Dipeptidase A/sangue , Fibrose Pulmonar/patologia , Fibrose Pulmonar/prevenção & controle , Ratos , Ratos Wistar , Sistema Renina-Angiotensina/efeitos dos fármacos , Silicose/patologia
11.
J Biol Regul Homeost Agents ; 33(2 Suppl. 1): 69-77, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31169006

RESUMO

Several techniques and different biological or artificial tissues have been proposed as graft to restore articular defects. However, among the numerous and heterogeneous procedures proposed over time, the current literature findings are not conclusive. The aim of the current study is to evaluate if human costal cartilage can be suitable as graft for restoring articular cartilage defects. Knee articular cartilage and costal cartilage samples were obtained respectively from patients that underwent anterior cruciate ligament reconstruction (samples from notch plasty) or knee joint replacement and ear reconstruction or rhinoplasty through rib graft. The samples were stained with hematoxylin eosin, safranine-O, Gomori paraldehyde-fuchsin and Von Kossa for light microscopy. Immunohistochemistry was performed using anti-collagen I, II, IV and anti-SOX9 antibodies. Furthermore, samples were analyzed by transmission electron microcopy (TEM). In both cartilage, the cells are arranged in quite similar layers and the matrix show the same hyaline appearance: presence of type II collagen and solphated glycosaminoglycans, and absence of type I collagen and SOX-9. The bigger difference between the two hyaline tissues is the presence of perichondrium that surrounds all the specimens of costal cartilage. It consists of two separate layers where the inner one seems to get thinner with aging. The results show that rib cartilage seems to be an adapt tissue as graft for articular cartilage repair from a histological point of view. However, to date its therapeutic potential remains to be clearly defined by animal and clinical studies.


Assuntos
Cartilagem Articular/cirurgia , Cartilagem Costal/transplante , Cartilagem Costal/ultraestrutura , Cartilagem Articular/lesões , Colágeno Tipo I/análise , Humanos , Imuno-Histoquímica , Articulação do Joelho , Microscopia , Microscopia Eletrônica de Transmissão , Costelas , Fatores de Transcrição SOX9/análise
12.
Clin Chem Lab Med ; 57(10): 1546-1555, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31085740

RESUMO

Background Biochemical bone turnover markers (BTM) are useful tools to assess bone remodeling at the cellular level. N-terminal propeptide of type I procollagen (PINP) has been recommended as a reference marker for bone formation in research studies. Methods We describe the results of a multicenter study for routine clinical laboratory assays for PINP in serum and plasma. Four centers (Athens, Greece [GR], Copenhagen, Denmark [DK], Liege, Belgium [BE] and Sheffield, United Kingdom [UK]) collected serum and plasma (EDTA) samples from 796 patients presenting to osteoporosis clinics. Specimens were analyzed in duplicate with each of the available routine clinical laboratory methods according to the manufacturers' instructions. Passing-Bablok regressions, Bland-Altman plots, V-shape evaluation method and the concordance correlation coefficient for PINP values between serum and plasma specimens and between methods were used to determine the agreement between results. A generalized linear model was employed to identify possible variables that affected the relationship between the methods. Results We showed that both EDTA plasma and serum were suitable for PINP determination. We observed a significant proportional bias between Orion radioimmunoassay and the automated methods for PINP (Roche Cobas and IDS iSYS), which both gave very similar results. The multivariate model did not improve the excellent correlation that was observed between the methods. Conclusions Harmonization of PINP assays is possible by applying a correction factor or correctly assigning the values of the calibrators. This work will benefit from further collaboration between assays manufacturers and clinical laboratory professionals.


Assuntos
Colágeno Tipo I/análise , Testes Diagnósticos de Rotina/normas , Fragmentos de Peptídeos/análise , Peptídeos/análise , Pró-Colágeno/análise , Adulto , Idoso , Bélgica , Bioensaio , Biomarcadores/sangue , Remodelação Óssea/fisiologia , Colágeno Tipo I/sangue , Dinamarca , Testes Diagnósticos de Rotina/métodos , Feminino , Grécia , Humanos , Imunoensaio/métodos , Imunoensaio/normas , Masculino , Pessoa de Meia-Idade , Osteoporose/metabolismo , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Valores de Referência , Reino Unido
13.
Life Sci ; 228: 30-34, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31004660

RESUMO

Collagen is the most abundant protein in mammalian systems; it can be found in organs such as bones, the liver, kidney, heart, teeth, and skin. Collagen provides the necessary structural framework for tissues in which it is found. However, if there are any alterations in the delicate balance of collagen types in the extracellular matrix (ECM), then problems arise. For example, increasing collagen I:III ratio would provide additional rigidity to tissue structure, whereas decreasing this ratio would provide elasticity and flexibility to the tissue. The proper function of tissues is reliant on this scale not tipping too far in either direction. Major players in the process of ECM remodeling, both normal and adverse, are the fibroblast cells via the secretion of collagen precursors and matrix metalloproteinases, with the latter responsible for ECM degradation. The collagen peptides created by the proteolytic cleavage of these collagen fibrils, while once thought to have an absence of function, have been shown over recent years to potentiate and regulate a variety of cellular processes acting through integrin receptors. Many collagen peptides have been identified from many different collagen types and have been shown to regulate processes such as cell proliferation, migration, apoptosis, and reduce angiogenesis. The collagen peptides of interest are those generated from the primary collagen type of tissue interstitial matrix, collagen type I, and the basement membrane, collagen type IV. Thus, this review looks to highlight some examples of unorthodox functional roles of collagen and its peptides in regulating physiological health and disease.


Assuntos
Colágeno Tipo IV/metabolismo , Colágeno Tipo I/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Animais , Apoptose , Movimento Celular , Proliferação de Células , Colágeno Tipo I/análise , Colágeno Tipo IV/análise , Matriz Extracelular/química , Humanos , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/metabolismo , Proteólise
14.
Ann Anat ; 224: 88-96, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31022516

RESUMO

BACKGROUND: Recent reports in rat models have shown that fibroblasts in the epiligament, an enveloping tissue of the ligament, are not static cells and play an important role during the early ligament healing of isolated grade III injury of the collateral ligaments of the knee. Fibroblasts produce collagen types I, III and V and infiltrate within the ligament body via the endoligament. In addition, similarities have been reported between the structure of the epiligament of the medial collateral ligament and anterior cruciate ligament of the knee in rat and in human. In line with the ascribed role of the epiligament tissue and the synthesis of these collagens and their role in ligament healing, the aim of this study was to determine their presence in the normal epiligament of the aforementioned ligaments in humans, to compare their differential expression and to present a novel hypothesis about the failure of healing of the anterior cruciate ligament in contrast to the medial collateral ligament. MATERIALS AND METHODS: We used samples from the mid-substance of the medial collateral and the anterior cruciate ligament of the knee joint, acquired from 12 fresh knee joints. Routine histological analysis was performed through hematoxylin and eosin stain, Mallory's trichrome stain and Van Gieson's stain. The immunohistochemical analysis was conducted using monoclonal antibodies against collagen type I and V and procollagen type III. The number of cells in the epiligament, endoligament and the ligament tissue was assessed quantitatively through a computerized system for image analysis NIS-Elements Advanced Research and Statistica software. RESULTS: Our observations revealed certain differences in the morphology of the epiligament, as well as variations in the expression of the investigated molecules. Expression of collagen type I was mostly low-positive (1+) in the epiligament and positive (2+) in the ligament tissue of both ligaments. Expression of procollagen type III was mostly positive (2+) in the epiligament and ligament tissue of the medial collateral ligament, low-positive (1+) in the epiligament and negative (0) in ligament tissue of the anterior cruciate ligament. Expression of collagen type V was predominantly low-positive (1+) in the epiligament and negative (0) in the ligament tissue of both ligaments. The immunoreactivity for all three molecules was always higher in the epiligament of the medial collateral ligament than that of the anterior cruciate ligament. CONCLUSIONS: The results of our study illustrate for the first time that fibroblasts in the human epiligament are indeed responsible for the synthesis of the main types of collagen participating in the early ligament healing, thus corresponding to previous data of the medial collateral ligament healing in animal models. The differences between the epiligament of the investigated ligaments could add a novel explanation for the failed anterior cruciate ligament healing.


Assuntos
Ligamento Cruzado Anterior/anatomia & histologia , Colágeno Tipo III/análise , Colágeno Tipo I/análise , Colágeno Tipo V/análise , Ligamento Colateral Médio do Joelho/anatomia & histologia , Ligamento Cruzado Anterior/química , Cadáver , Corantes/classificação , Feminino , Humanos , Imuno-Histoquímica , Masculino , Ligamento Colateral Médio do Joelho/química , Pessoa de Meia-Idade , Coloração e Rotulagem/métodos
15.
Rapid Commun Mass Spectrom ; 33(16): 1311-1317, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31017708

RESUMO

RATIONALE: The trophic enrichment factor (TEF) is a parameter reflecting the difference in isotopic ratio between a consumer's tissues and diet, used in isotopic ecology and paleoecology to track dietary habits. The TEF of sulfur is believed to be low, but was, until now, only documented in a limited number of taxa. In this study we use a subfossil accumulation of bones from a red fox (Vulpes vulpes) den to verify the TEF for sulfur in fox bone collagen. METHODS: Collagen was extracted from 30 samples of subfossil bones, including foxes and their prey. The δ34 S values of the bone collagen samples were measured with an elemental analyzer connected to an isotope ratio mass spectrometer. The TEF was calculated as [Δ34 S = (mean δ34 S in predator) - (mean δ34 S in prey)], using taphonomic indices to estimate the mean diet, and calculated separately for different age classes of the predator. RESULTS: We modeled 12 variants of TEF for different estimations of the diet composition and for three fox age classes (adult, subadult, and juvenile). The estimated TEF values range from -0.54 to +0.03‰ and are similar to TEFs known for other mammals. Absolute TEF values are nearly equal to or lower than the analytical error, which is ±0.4‰. CONCLUSIONS: For the first time, we present direct δ34 S data for the bone collagen of a free-living predator and its naturally selected prey. Our results indicate very low or even slightly negative TEF values for sulfur. Furthermore, according to our results, the δ34 S value should not be considered a reliable indicator of trophic position in terrestrial food webs but rather, it should be used to disentangle different food webs based on different primary producers.


Assuntos
Osso e Ossos/química , Colágeno Tipo I/análise , Comportamento Alimentar/fisiologia , Raposas/fisiologia , Isótopos de Enxofre/análise , Animais , Colágeno Tipo I/química , Dieta , Cadeia Alimentar , Paleontologia
16.
J Biomater Appl ; 33(10): 1301-1313, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30791848

RESUMO

The biocompatibility and bioactivity of injectable acellular extracellular matrix nominates its use as an optimal candidate for cell delivery, serving as a reconstructive scaffold. In this study, we investigated the feasibility of preparing a blood vessel matrix (BVM) hydrogel, which revealed its pro-angiogenic effects in vitro and its therapeutic effects in an in vivo skin flap model. Aortic and abdominal aortic arteries from pigs were acellularized by Triton-X 100 and confirmed by hematoxylin and eosin and 4,6-diamidino-2-phenylindole staining. Different concentrations of blood vessel matrix hydrogel were generated successfully through enzymatic digestion, neutralization, and gelation. Hematoxylin and eosin staining, Masson's trichrome staining, collagen type I immunohistochemistry staining, and enzyme-linked immunosorbent assays showed that type I collagen and some growth factors were retained in the hydrogel. Scanning electron microscopy demonstrated the different diametric fibrils in blood vessel matrix hydrogels. A blood vessel matrix hydrogel-coated plate promoted the tube formation of human umbilical vein endothelial cells in vitro. After injection into skin flaps, the hydrogel improved the flap survival rate and increased blood perfusion and capillary density. These results indicated that we successfully prepared a blood vessel matrix hydrogel and demonstrated its general characteristics and angiogenic effects in vitro and in vivo.


Assuntos
Vasos Sanguíneos/química , Matriz Extracelular/química , Células Endoteliais da Veia Umbilical Humana/citologia , Neovascularização Fisiológica , Tecidos Suporte/química , Animais , Vasos Sanguíneos/ultraestrutura , Colágeno Tipo I/análise , Matriz Extracelular/ultraestrutura , Humanos , Hidrogéis/química , Suínos , Engenharia Tecidual
17.
J Biol Chem ; 294(16): 6578-6590, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30733334

RESUMO

Lysyl oxidase-generated intermolecular cross-links are essential for the tensile strength of collagen fibrils. Two cross-linking pathways can be defined, one based on telopeptide lysine aldehydes and another on telopeptide hydroxylysine aldehydes. Since the 1970s it has been accepted that the mature cross-linking structures on the lysine aldehyde pathway, which dominates in skin and cornea, incorporate histidine residues. Here, using a range of MS-based methods, we re-examined this conclusion and found that telopeptide aldol dimerization is the primary mechanism for stable cross-link formation. The C-telopeptide aldol dimers formed labile addition products with glucosylgalactosyl hydroxylysine at α1(I)K87 in adjacent collagen molecules that resisted borohydride reduction and after acid hydrolysis produced histidinohydroxylysinonorleucine (HHL), but only from species with a histidine in their α1(I) C-telopeptide sequence. Peptide MS analyses and the lack of HHL formation in rat and mouse skin, species that lack an α1(I) C-telopeptide histidine, revealed that HHL is a laboratory artifact rather than a natural cross-linking structure. Our experimental results also establish that histidinohydroxymerodesmosine is produced by borohydride reduction of N-telopeptide allysine aldol dimers in aldimine intermolecular linkage to nonglycosylated α1(I) K930. Borohydride reduction of the aldimine promotes an accompanying base-catalyzed Michael addition of α1(I) H932 imidazole to the α,ß-unsaturated aldol. These aldehydes are intramolecular at the N terminus but at the C terminus they can be both intramolecular and intermolecular according to present and earlier findings.


Assuntos
Aldeídos/análise , Colágeno Tipo I/análise , Dipeptídeos/análise , Histidina/análogos & derivados , Hidroxilisina/análogos & derivados , Peptídeos/análise , Pele/química , Aldeídos/química , Animais , Artefatos , Bovinos , Colágeno Tipo I/química , Histidina/análise , Hidroxilisina/análise , Hidroxilisina/química , Peptídeos/química , Proteína-Lisina 6-Oxidase/química
18.
Anal Chem ; 91(3): 1796-1800, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30599131

RESUMO

Leather produced from crocodile, alligator, and caiman skin is widely used in the fashion industry. Crocodilian leather is generally more expensive than mammalian leather, and the value greatly differs even between the crocodilian species. However, inappropriate labeling of the animal source on leather products sometimes arises from accidental or fraudulent substitution, which is difficult to unambiguously detect by existing methods. In the present study, animal source identification of crocodilian leather was carried out using type I collagen-derived marker peptides generated after dechroming, heat denaturation, and trypsin digestion. Definitive discrimination between the three crocodilian species and also a related species, lizard, was achieved based on the detection patterns of selected six marker peptides, determined by LC-MS. Furthermore, powdering of the leather samples enabled a reduction in the sample amount required and allowed the elimination of the dechroming step. Approximately 100 µg of powder was taken from commercial leather watch straps by filing, resulting in only slight damage to the undersides of the straps. The animal sources of the crocodilian products and also a crocodile-embossed calf product were successfully identified using a combination of the crocodilian marker peptides and previously established mammalian marker peptides. This semi-nondestructive species identification method is not only useful for certification of leather products but also for monitoring of international trade of leather and skin.


Assuntos
Colágeno Tipo I/análise , Peptídeos/análise , Proteínas de Répteis/análise , Pele/química , Jacarés e Crocodilos , Sequência de Aminoácidos , Animais , Biomarcadores/análise , Biomarcadores/química , Cromatografia Líquida/métodos , Colágeno Tipo I/química , Proteólise , Proteínas de Répteis/química , Espectrometria de Massas em Tandem , Tripsina/química
19.
Reprod Sci ; 26(6): 724-733, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30185141

RESUMO

AIMS: Hypoxia and the resulting oxidative stress play a major role in postoperative tissue fibrosis. The objective of this study was to determine the effect of l-alanyl-l-glutamine (Ala-Gln) on key markers of postoperative tissue fibrosis: hypoxia-inducible factor (HIF) 1α and type I collagen. METHODS: Primary cultures of human normal peritoneal fibroblasts (NPF) established from normal peritoneal tissue were treated with increasing doses of Ala-Gln (0, 1, 2, or 10 mM) with hypoxia ([2% O2] 0-48 hours; continuous hypoxia) or after hypoxia (0.5, 1, 2, 4 hours) and restoration of normoxia (episodic hypoxia) with immediate treatment with Ala-Gln. Hypoxia-inducible factor 1α and type 1 collagen levels were determined by enzyme-linked immunosorbent assay. Data were analyzed with 1-way analysis of variance followed by Tukey tests with Bonferroni correction. RESULTS: Hypoxia-inducible factor 1α and type I collagen levels increased in untreated controls by 3- to 4-fold in response to continuous and episodic hypoxia in human NPF. Under continuous hypoxia, HIF-1α and type I collagen levels were suppressed by Ala-Gln in a dose-dependent manner. l-alanyl-l-glutamine treatment after episodic hypoxia also suppressed HIF-1α and type I collagen levels for up to 24 hours for all doses and up to 48 hours at the highest dose, regardless of exposure time to hypoxia. CONCLUSIONS: l-alanyl-l-glutamine significantly suppressed hypoxia-induced levels of key tissue fibrosis (adhesion) phenotype markers under conditions of continuous as well as episodic hypoxia in vitro. This effect of glutamine on molecular events involved in the cellular response to insult or injury suggests potential therapeutic value for glutamine in the prevention of postoperative tissue fibrosis.


Assuntos
Dipeptídeos/farmacologia , Fibrose/metabolismo , Complicações Pós-Operatórias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Aderências Teciduais/prevenção & controle , Biomarcadores/análise , Hipóxia Celular , Células Cultivadas , Colágeno Tipo I/análise , Dipeptídeos/administração & dosagem , Fibroblastos/química , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Peritônio/citologia
20.
Surg Obes Relat Dis ; 15(1): 117-125, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30471928

RESUMO

BACKGROUND: In bariatric surgery, preoperative very low-calorie diets (VLCD) may better meet the technical demands of surgery by shrinking the liver. However, diets may affect tissue healing and influence bowel anastomosis in an as-yet-undefined manner. OBJECTIVE: This randomized controlled trial aimed to examine the effect on collagen deposition in wounds in patients on a 4-week VLCD before laparoscopic gastric bypass. SETTING: University hospital. METHODS: The trial was undertaken in patients undergoing laparoscopic Roux-en-Y gastric bypass, with a control group (n = 10) on normal diet and an intervention group (n = 10) on VLCD (800 kcal) for 4 weeks. The primary outcome measured was expression of collagen I and III in skin wounds, with biopsies taken before and after the diet and 7 days postoperatively as a surrogate of anastomotic healing. Secondary outcome measures included liver volume and fibrosis score, body composition, operating time, blood loss, hospital stay, and complications. RESULTS: Patients in both groups were similar in age, sex, body mass index (53.4 versus 52.8 kg/m2), co-morbidities, liver volume, and body composition. Expression of mature collagen type I was significantly decreased in diet patients compared with controls after 4 weeks of diet and 7 days after surgery. This was significant decrease in liver volume (23% versus 2%, P = .03) but no difference in operating times (129 versus 139 min, P = .16), blood loss, length of stay, or incidence of complications. CONCLUSIONS: Preoperative diets shrink liver volume and decrease expression of mature collagen in wounds after surgery. Whether the latter has a detrimental effect on clinical outcomes requires further evaluation.


Assuntos
Cirurgia Bariátrica/métodos , Dieta Redutora , Fígado/fisiologia , Obesidade Mórbida , Cicatrização/fisiologia , Adulto , Colágeno Tipo I/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/dietoterapia , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/fisiopatologia , Cuidados Pré-Operatórios , Resultado do Tratamento
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