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1.
J Sci Food Agric ; 103(14): 6884-6894, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37286475

RESUMO

BACKGROUND: Porcine nasal cartilage type II collagen-derived peptides (PNCPs) may be complexed with calcium to provide a highly bioavailable, low-cost, and effective calcium food supplement. However, the calcium-binding characteristics of PNCPs have not yet been investigated. In the present study, calcium-binding peptides were derived from porcine nasal cartilage type II collagen and the resulting PNCPs-Ca complex was characterized. RESULTS: The study reveals that the calcium-binding capacity of PNCPs is closely related to enzymatic hydrolysis conditions. The highest calcium-binding capacity of PNCPs was observed at a hydrolysis time of 4 h, temperature of 40 °C, enzyme dosage of 1%, and solid-to-liquid ratio of 1:10. Scanning electron microscopy and energy dispersive X-ray spectroscopy revealed that the PNCPs had a pronounced capacity for calcium binding, with the PNCPs-Ca complex exhibiting a clustered structure consisting of aggregated spherical particles. Fourier-transform infrared spectroscopy, fluorescence spectroscopy, X-ray diffraction, dynamic light scattering, amino acid composition, and molecular weight distribution analyses all indicated that the PNCPs and calcium complexed via the carboxyl oxygen and amino nitrogen atoms, leading to the formation of a ß-sheet structure during the chelation process. In addition, the stability of the PNCPs-Ca complex was maintained over a range of pH values consistent with those found in the human gastrointestinal tract, facilitating calcium absorption. CONCLUSION: These research findings suggest the feasibility of converting by-products from livestock processing into calcium-binding peptides, providing a scientific basis for the development of novel calcium supplements and the potential reduction of resource waste. © 2023 Society of Chemical Industry.


Assuntos
Cálcio , Cartilagens Nasais , Humanos , Animais , Suínos , Cálcio/metabolismo , Colágeno Tipo II , Cartilagens Nasais/química , Cartilagens Nasais/metabolismo , Peptídeos/química , Cálcio da Dieta/análise
2.
J Biomed Mater Res A ; 107(4): 893-903, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30650239

RESUMO

Nasal reconstruction remains a challenge for every reconstructive surgeon. Alloplastic implants are proposed to repair nasal cartilaginous defects but they are often associated with high rates of extrusion and infection and poor biocompatibility. In this context, a porous polymeric scaffold filled with an autologous cartilage gel would be advantageous. In this study, we evaluated the capacity of IEIK13 self-assembling peptide (SAP) to serve as support to form such cartilage gel. Human nasal chondrocytes (HNC) were first amplified with FGF-2 and insulin, and then redifferentiated in IEIK13 with BMP-2, insulin, and T3 (BIT). Our results demonstrate that IEIK13 fosters HNC growth and survival. HNC phenotype was assessed by RT-PCR analysis and neo-synthesized extracellular matrix was characterized by western blotting and immunohistochemistry analysis. BIT-treated cells embedded in IEIK13 displayed round morphology and expressed cartilage-specific markers such as type II and type IX collagens and aggrecan. In addition, we did not detect significant production of type I and type X collagens and gene products of dedifferentiated and hypertrophic chondrocytes that are unwanted in hyaline cartilage. The whole of these results indicates that the SAP IEIK13 represents a suitable support for hydrogel-based tissue engineering of nasal cartilage. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 893-903, 2019.


Assuntos
Condrócitos/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Hidrogéis/química , Cartilagens Nasais/metabolismo , Peptídeos/química , Adulto , Condrócitos/citologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cartilagens Nasais/citologia
3.
Oral Dis ; 24(1-2): 78-83, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29480643

RESUMO

Craniofacial development is a delicate process that involves complex interactions among cells of multiple developmental origins, their migration, proliferation, and differentiation. Tissue morphogenesis of the craniofacial skeleton depends on genetic and environmental factors, and on specific signaling pathways, which are still not well understood. Developmental defects of the midface caused by the absence, delays, or premature fusion of nasal and maxillary prominences vary in severity; leading to clefts, hypoplasias, and midline expansion. In the current review, we focus on the importance of the chondrocranium in craniofacial growth and how its impaired development leads to midface hypoplasia. More importantly, we reported how Matrix Gla protein (MGP), a potent inhibitor of extracellular matrix mineralization, facilitates midface development by preventing ectopic calcification of the nasal septum. In fact, MGP may act as a common link in multiple developmental pathologies all showing midface hypoplasia caused by abnormal cartilage calcification. This brief review discusses the gap in knowledge in the field, raises pertinent questions, which remain unanswered, and sheds light on the future research directions.


Assuntos
Calcinose/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Face/anormalidades , Ossos Faciais/crescimento & desenvolvimento , Desenvolvimento Maxilofacial , Cartilagens Nasais/crescimento & desenvolvimento , Calcinose/congênito , Matriz Extracelular/metabolismo , Ossos Faciais/anormalidades , Humanos , Cartilagens Nasais/anormalidades , Cartilagens Nasais/metabolismo , Proteína de Matriz Gla
4.
Laryngoscope ; 127(11): E399-E407, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28846132

RESUMO

OBJECTIVES/HYPOTHESIS: To characterize the histologic and biochemical properties of auricular and septal cartilage and analyze age-related changes in middle-aged to older adults. STUDY DESIGN: Cross-sectional study of auricular and septal cartilage from 33 fresh cadavers. METHODS: Auricular and septal cartilage specimens were stained using Safranin O for glycosaminoglycans, Verhoeff's stain for elastin, and Masson's trichrome for collagen. Percentage of tissue stained, cell density and size were quantified. Relationships between donor characteristics and histologic properties were evaluated using mixed model analyses. RESULTS: The average donor age was 75 years (standard deviation = 11 years; range, 55-93 years). In auricular cartilage, each 1-year increase in age was associated with a 0.97% decrease in glycosaminoglycans (P < .001) and a 0.98% decrease in elastin (P < .001). In septal cartilage, glycosaminoglycans decreased 2.4% per year (P < .001). Age did not affect collagen content significantly in auricular (P = .417) or septal cartilage (P = .284). Cell density and cell size declined with age in auricular (both P < .001) and septal cartilage (P = .044, P = .032, respectively). Compared to septal cartilage in patients of all ages, auricular cartilage had more glycosaminoglycans, less collagen, higher cell density, and smaller cells. CONCLUSIONS: In auricular and septal cartilage, glycosaminoglycans, elastin, cell density, and cell size decrease significantly with age in patients over 55 years of age. Glycosaminoglycan content declines faster with age in septal cartilage than auricular cartilage. These age-related changes may affect biomechanical properties and tissue viability, and thereby have implications for graft choice in functional, aesthetic, and reconstructive nasal surgery. LEVEL OF EVIDENCE: NA. Laryngoscope, 127:E399-E407, 2017.


Assuntos
Envelhecimento/fisiologia , Cartilagem da Orelha/patologia , Cartilagens Nasais/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Cadáver , Estudos Transversais , Cartilagem da Orelha/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Pessoa de Meia-Idade , Cartilagens Nasais/metabolismo , Coloração e Rotulagem
5.
Eur Arch Otorhinolaryngol ; 274(9): 3503-3512, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28669050

RESUMO

The aim of this study was to analyze the role of Ki-67, p53, and the "aberrant p53 pattern" in squamous cell carcinomas of the nasal vestibule. Patients between 1995 and 2014 were included. Baseline characteristics and outcome were analyzed with respect to immunohistochemical staining of Ki-67 and p53. "Aberrant p53 pattern" was represented by a moderate or strong staining of at least 60% of the tumor cells or a complete absence of immunoreactivity. Forty-six patients were included of whom 31 (67.4%) were available for Ki-67 and 32 (69.9%) for p53 immunohistochemistry. The "aberrant pattern" of p53 was present in 50% of the patients. While immunoreactivity for both Ki-67 and p53 was not related to each other or outcome, the "aberrant p53 pattern" was associated with a worse disease-free survival (p = 0.014). The "aberrant p53 pattern" is a negative prognostic factor in squamous cell carcinoma of the nasal vestibule and might enable a patient-tailored treatment.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Nasais/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Cartilagens Nasais/metabolismo , Cartilagens Nasais/patologia , Estadiamento de Neoplasias , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/mortalidade , Prognóstico , Taxa de Sobrevida/tendências , Suíça/epidemiologia
6.
Regen Med ; 12(3): 303-314, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28524733

RESUMO

This review provides an update on cartilage tissue engineering with particular focus on the head and neck. It is aimed at scientists and clinicians who are interested in tissue engineering and its clinical applicability. Principal tissue engineering strategies are summarized in the first part of this review. In the second part, current clinical approaches to auricular, nasal and tracheal reconstruction are discussed from a surgical perspective. By this approach, the requirements for clinical applicability are outlined and new insight into relevant aims of research is given to accelerate the transfer from bench to bedside.


Assuntos
Cartilagem da Orelha , Cartilagens Nasais , Procedimentos de Cirurgia Plástica/métodos , Engenharia Tecidual/métodos , Traqueia , Animais , Cartilagem da Orelha/metabolismo , Cartilagem da Orelha/cirurgia , Humanos , Cartilagens Nasais/metabolismo , Cartilagens Nasais/cirurgia , Traqueia/metabolismo , Traqueia/cirurgia
7.
Tissue Cell ; 49(4): 503-513, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28515001

RESUMO

Chondrocyte based regenerative therapies for intervertebral disc repair such as Autologous Disc Cell Transplantation (ADCT, CODON) and allogeneic juvenile chondrocyte implantation (NuQu®, ISTO Technologies) have demonstrated good outcomes in clinical trials. However concerns remain with the supply demand reconciliation and issues surrounding immunoreactivity which exist for allogeneic-type technologies. The use of stem cells is challenging due to high growth factor requirements, regulatory barriers and differentiation towards a stable phenotype. Therefore, there is a need to identify alternative non-disc cell sources for the development and clinical translation of next generation therapies for IVD regeneration. In this study, we compared Nasal Chondrocytes (NC) as a non-disc alternative chondrocyte source with Articular Chondrocytes (AC) in terms of cell yield, morphology, proliferation kinetics and ability to produce key extracellular matrix components under 5% and 20% oxygen conditions, with and without exogenous TGF-ß supplementation. Results indicated that NC maintained proliferative capacity with high amounts of sGAG and lower collagen accumulation in the absence of TGF-ß supplementation under 5% oxygen conditions. Importantly, osteogenesis and calcification was inhibited for NC when cultured in IVD-like microenvironmental conditions. The present study provides a rationale for the exploration of nasal chondrocytes as a promising, potent and clinically feasible autologous cell source for putative IVD repair strategies.


Assuntos
Cartilagem Articular , Condrócitos , Matriz Extracelular/metabolismo , Disco Intervertebral , Cartilagens Nasais , Medicina Regenerativa/métodos , Animais , Cartilagem Articular/citologia , Cartilagem Articular/metabolismo , Bovinos , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Condrócitos/transplante , Feminino , Cartilagens Nasais/citologia , Cartilagens Nasais/metabolismo
8.
Stem Cells Transl Med ; 6(2): 601-612, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28191761

RESUMO

Craniofacial deformities caused by congenital defects or trauma remain challenges for clinicians, whereas current surgical interventions present limited therapeutic outcomes. Injection of bone marrow-derived mesenchymal stem cells (BMSCs) into the defect is highly desirable because such a procedure is microinvasive and grafts are more flexible to fill the lesions. However, preventing hypertrophic transition and morphological contraction remain significant challenges. We have developed an "all host derived" cell transplantation system composed of chondrocyte brick (CB)-enriched platelet-rich plasma (P) gel and BMSCs (B). Without exogenous biomaterials or growth factors, such grafts regenerate cartilage efficiently and present great clinical promise. In immunodeficient mice, we compared performance of BMSCs and BMSCs lacking angiogenic potential in CB-B-P constructs and followed the cartilage maturation process by histology, immunostaining, micro-computed tomography, and protein analysis. We determined that angiogenesis occurred quickly inside rudimentary cartilage derived from CB-B-P constructs after implantation, which improved tissue survival, tissue growth, and production of chondrogenic signals from chondrocytes. In contrast, silencing angiogenic potential of BMSCs led to poor chondrogenesis accompanied by necrosis. Chondrocyte bricks merged rapidly with angiogenesis, which constituted an enclosed chondrogenic niche and effectively inhibited runt-related transcription factor-2-dependent hypertrophic transition of BMSCs as well as endochondral ossification; progressive chondrogenic differentiation of BMSCs resulted in vascularization regression, thus favoring persistent chondrogenesis and effectively augmenting nasal cartilage. In conclusion, these findings provided a novel, efficient approach to regenerating cartilage tissues in vivo. Chondrocyte bricks mixed with P provide transient vascularization and a persistently chondrogenic microenvironment for BMSCs; this provides a mini-invasive approach for craniofacial cartilage reconstruction. Stem Cells Translational Medicine 2017;6:601-612.


Assuntos
Condrócitos/metabolismo , Condrócitos/transplante , Condrogênese , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Cartilagens Nasais/irrigação sanguínea , Cartilagens Nasais/cirurgia , Neovascularização Fisiológica , Engenharia Tecidual/métodos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Comunicação Celular , Células Cultivadas , Técnicas de Cocultura , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos Nus , Camundongos SCID , Cartilagens Nasais/metabolismo , Cartilagens Nasais/fisiopatologia , Transdução de Sinais , Alicerces Teciduais
9.
Development ; 142(7): 1357-67, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25742798

RESUMO

Bone morphogenetic protein (BMP) signaling plays many roles in skull morphogenesis. We have previously reported that enhanced BMP signaling through the BMP type IA receptor (BMPR1A) in cranial neural crest cells causes craniosynostosis during postnatal development. Additionally, we observed that 55% of Bmpr1a mutant mice show neonatal lethality characterized by a distended gastrointestinal tract. Here, we show that severely affected mutants exhibit defective nasal cartilage, failure of fusion between the nasal septum and the secondary palate, and higher levels of phosphorylated SMAD1 and SMAD5 in the nasal tissue. TUNEL demonstrated an increase in apoptosis in both condensing mesenchymal tissues and cartilage of the nasal region in mutants. The levels of p53 (TRP53) tumor suppressor protein were also increased in the same tissue. Injection of pifithrin-α, a chemical inhibitor of p53, into pregnant mice prevented neonatal lethality while concomitantly reducing apoptosis in nasal cartilage primordia, suggesting that enhanced BMP signaling induces p53-mediated apoptosis in the nasal cartilage. The expression of Bax and caspase 3, downstream targets of p53, was increased in the mutants; however, the p53 expression level was unchanged. It has been reported that MDM2 interacts with p53 to promote degradation. We found that the amount of MDM2-p53 complex was decreased in all mutants, and the most severely affected mutants had the largest decrease. Our previous finding that the BMP signaling component SMAD1 prevents MDM2-mediated p53 degradation coupled with our new data indicate that augmented BMP signaling induces p53-mediated apoptosis by prevention of p53 degradation in developing nasal cartilage. Thus, an appropriate level of BMP signaling is required for proper craniofacial morphogenesis.


Assuntos
Apoptose , Proteínas Morfogenéticas Ósseas/metabolismo , Morfogênese , Cartilagens Nasais/embriologia , Crista Neural/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Benzotiazóis/farmacologia , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Perda do Embrião/metabolismo , Perda do Embrião/patologia , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/patologia , Fatores de Crescimento de Fibroblastos/metabolismo , Integrases/metabolismo , Mesoderma/efeitos dos fármacos , Mesoderma/embriologia , Mesoderma/patologia , Camundongos , Morfogênese/efeitos dos fármacos , Mutação/genética , Cartilagens Nasais/anormalidades , Cartilagens Nasais/metabolismo , Cartilagens Nasais/patologia , Mucosa Nasal/metabolismo , Crista Neural/efeitos dos fármacos , Crista Neural/embriologia , Nariz/embriologia , Ligação Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Tolueno/análogos & derivados , Tolueno/farmacologia
10.
Eur Arch Otorhinolaryngol ; 272(7): 1667-71, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25129374

RESUMO

Any abnormality of collagen may affect the tissues with higher collagen content, e.g., joints, heart valves, and great arteries. Mitral valve prolapse (MVP) is a characteristic of generalized collagen abnormality. Nasal septum (NS) is constituted by osseous and cartilaginous septums that are highly rich in collagen. We evaluated the co-existence of deviation of NS (DNS) in patients with MVP. We retrospectively evaluated the recordings of echocardiographic and nasal examinations of subjects with MVP and DNS. We analyzed the features of MVP and anatomical classification of DNS among subjects. Totally, 74 patients with DNS and 38 subjects with normal nasal passage were enrolled to the study. Presence of MVP was significantly higher in patients with DNS compared to normal subjects (63 vs 26%, p < 0.001). Prolapse of anterior, posterior and both leaflets was higher in patients with DNS. Thickness of anterior mitral leaflet was significantly increased in patients with DNS (3.57 ± 0.68 vs 4.59 ± 1.1 mm, p < 0.001) compared to normal subjects. Type I, II, and III, IV DNS were higher in frequency in patients with MVP while type V and VI were higher in normal subjects. DNS is highly co-existent with MVP and increased thickness of mitral anterior leaflet. Generalized abnormality of collagen which is the main component of mitral valves and nasal septum may be accounted for co-existence of MVP and DNS. Also co-existence of them may exaggerate the symptoms of patients with MVP due to limited airflow through the nasal passage.


Assuntos
Prolapso da Valva Mitral , Septo Nasal/patologia , Deformidades Adquiridas Nasais , Nariz/anormalidades , Adulto , Colágeno/metabolismo , Ecocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/patologia , Prolapso da Valva Mitral/complicações , Prolapso da Valva Mitral/diagnóstico , Cartilagens Nasais/metabolismo , Cartilagens Nasais/patologia , Deformidades Adquiridas Nasais/complicações , Deformidades Adquiridas Nasais/diagnóstico , Estudos Retrospectivos
11.
Arthritis Rheum ; 65(7): 1822-30, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23575963

RESUMO

OBJECTIVE: To examine the ability of a broad-spectrum histone deacetylase (HDAC) inhibitor to protect cartilage in vivo, and to explore the effects of class-selective HDAC inhibitors and small interfering RNA (siRNA)-induced knockdown of HDACs on metalloproteinase expression and cartilage degradation in vitro. METHODS: A destabilization of the medial meniscus (DMM) model was used to assess the in vivo activity of the HDAC inhibitor trichostatin A (TSA). Human articular chondrocytes (HACs) and SW-1353 chondrosarcoma cells were treated with cytokines and TSA, valproic acid, MS-275, or siRNA, and quantitative reverse transcription-polymerase chain reaction was performed to determine the effect of treatment on metalloproteinase expression. HDAC inhibitor activity was detected by Western blotting. A bovine nasal cartilage (BNC) explant assay was performed to measure cartilage resorption in vitro. RESULTS: Systemically administered TSA protected cartilage in the DMM model. TSA, valproic acid, and MS-275 repressed cytokine-induced MMP1 and MMP13 expression in HACs. Knockdown of each class I HDAC diminished interleukin-1-induced MMP13 expression. All of the HDAC inhibitors prevented degradation of BNC, in which TSA and MS-275 repressed cytokine-induced MMP expression. CONCLUSION: Inhibition of class I HDACs (HDAC-1, HDAC-2, HDAC-3) by MS-275 or by specific depletion of HDACs is capable of repressing cytokine-induced metalloproteinase expression in cartilage cells and BNC explants, resulting in inhibition of cartilage resorption. These observations indicate that specific inhibition of class I HDACs is a possible therapeutic strategy in the arthritides.


Assuntos
Benzamidas/farmacologia , Condrócitos/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Metaloproteases/efeitos dos fármacos , Cartilagens Nasais/efeitos dos fármacos , Osteoartrite do Joelho , Piridinas/farmacologia , Animais , Bovinos , Linhagem Celular Tumoral , Células Cultivadas , Condrócitos/metabolismo , Modelos Animais de Doenças , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Metaloproteases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Cartilagens Nasais/metabolismo , RNA Interferente Pequeno/farmacologia , Tubulina (Proteína)/efeitos dos fármacos , Tubulina (Proteína)/metabolismo
12.
Ann Rheum Dis ; 71(3): 455-62, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22072016

RESUMO

OBJECTIVES: To investigate the effect of leptin on cartilage destruction. METHODS: Collagen release was assessed in bovine cartilage explant cultures, while collagenolytic and gelatinolytic activities in culture supernatants were determined by bioassay and gelatin zymography. The expression of matrix metalloproteinases (MMP) was analysed by real-time RT-PCR. Signalling pathway activation was studied by immunoblotting. Leptin levels in cultured osteoarthritic joint infrapatellar fat pad or peri-enthesal deposit supernatants were measured by immunoassay. RESULTS: Leptin, either alone or in synergy with IL-1, significantly induced collagen release from bovine cartilage by upregulating collagenolytic and gelatinolytic activity. In chondrocytes, leptin induced MMP1 and MMP13 expression with a concomitant activation of STAT1, STAT3, STAT5, MAPK (JNK, Erk, p38), Akt and NF-κB signalling pathways. Selective inhibitor blockade of PI3K, p38, Erk and Akt pathways significantly reduced MMP1 and MMP13 expression in chondrocytes, and reduced cartilage collagen release induced by leptin or leptin plus IL-1. JNK inhibition had no effect on leptin-induced MMP13 expression or leptin plus IL-1-induced cartilage collagen release. Conditioned media from cultured white adipose tissue (WAT) from osteoarthritis knee joint fat pads contained leptin, induced cartilage collagen release and increased MMP1 and MMP13 expression in chondrocytes; the latter being partly blocked with an anti-leptin antibody. CONCLUSIONS: Leptin acts as a pro-inflammatory adipokine with a catabolic role on cartilage metabolism via the upregulation of proteolytic enzymes and acts synergistically with other pro-inflammatory stimuli. This suggests that the infrapatellar fat pad and other WAT in arthritic joints are local producers of leptin, which may contribute to the inflammatory and degenerative processes in cartilage catabolism, providing a mechanistic link between obesity and osteoarthritis.


Assuntos
Tecido Adiposo Branco/metabolismo , Cartilagem Articular/metabolismo , Leptina/fisiologia , Metaloproteinases da Matriz/fisiologia , Animais , Bovinos , Células Cultivadas , Colágeno/metabolismo , Colagenases/biossíntese , Colagenases/genética , Meios de Cultivo Condicionados , Relação Dose-Resposta a Droga , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Mediadores da Inflamação/farmacologia , Leptina/biossíntese , Leptina/farmacologia , Metaloproteinases da Matriz/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Cartilagens Nasais/efeitos dos fármacos , Cartilagens Nasais/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Técnicas de Cultura de Tecidos
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