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1.
Br J Pharmacol ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32022249

RESUMO

BACKGROUND AND PURPOSE: Regulating macrophage-hepatocyte crosstalk through P2X7 receptor (P2X7R) has led to the emergence of new pharmacologic strategies to reverse alcoholic hepatosteatosis. We investigated how tetrahydroxystilbene glucoside (2354glu) purified from Polygonum multiflorum modulates macrophage-hepatocyte crosstalk during alcoholic hepatosteatosis. EXPERIMENTAL APPROACH: Alcoholic hepatosteatosis was established by intragastrically administering ethanol to C57BL/6 mice. HepG2 cells were incubated in conditioned medium from LPS/ATP-activated THP-1 human macrophages with silenced or overexpressed P2X7R. THP-1 macrophages or mouse peritoneal macrophages were pretreated with 2354glu for 1 h prior to LPS/ATP stimulation. HepG2 cells were cultured with the conditioned medium from the LPS/ATP-activated THP-1 macrophages. KEY RESULTS: Knockdown or overexpression of P2X7R in THP-1 macrophages altered the release of mature IL-1ß. P2X7R gene expression in the THP-1 macrophages modulated lipid metabolism in the HepG2 cells via LKB-AMPK axis. 2354glu significantly ameliorated hepatosteatosis in mice after alcohol expose by regulating LKB1-AMPK-SREBP1 axis and its target genes. The suppression of P2X7R activation by 2354glu administration inhibited IL-1ß release, and reduced macrophage and neutrophil infiltration. The expression of P2X7R, caspase-1 and NF-κB, the release of IL-1ß, calcium influx and PI uptake were reduced by 2354glu in macrophages stimulated with LPS/ATP. SIRT1-LKB1-AMPK-SREBP1 axis-mediated lipid accumulation in HepG2 cells was reduced, when HepG2 cells were cultured with conditioned medium from LPS/ATP-activated THP-1 macrophages pretreated with 2354glu. CONCLUSIONS AND IMPLICATIONS: Alteration of P2X7R in macrophages might regulate lipid accumulation in hepatocytes during alcoholic hepatosteatosis, and 2354glu might be a promising candidate that targets P2X7R in macrophages interacting with hepatocytes during alcoholic hepatosteatosis.

2.
Oral Dis ; 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31901146

RESUMO

OBJECTIVE: The temporomandibular joint (TMJ) displays a high remodelling capability in response to occlusion changes. The purpose of the current study was to investigate the responses of TMJ condyles of growing mice to the installation of a unilateral anterior crossbite (UAC) prosthesis and the replacement of the UAC prothesis with a bilateral anterior elevation (BAE) prosthesis. MATERIALS AND METHODS: C57BL/6J mice were randomly assigned to the blank control and experimental groups. In mice in the experimental groups, UAC was created, while in others, BAE was created after the creation of UAC or removal of UAC. Changes in TMJ condylar cartilage and subchondral bone were assessed. RESULTS: The degradation of condylar cartilage induced by UAC was reversed by BAE, as evaluated by cartilage histochemical changes, collagen II-positive area, collagen X-positive chondrocytes and expression levels of Adamts-5, Mmp13, Tnf-α and Il-1ß. Subchondral bone was assessed based on the subchondral bone volume, the number of TRAP-positive cells and the Opg/Rankl ratio. CONCLUSION: The growing mouse TMJ condyle displays a high remodelling capability, which can be degenerative or rehabilitative in response to the creation of UAC and the replacement of UAC with BAE. Early correction of occlusion is beneficial for the recovery of degenerative condyles.

3.
Autophagy ; 16(2): 271-288, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31007149

RESUMO

A switch from autophagy to apoptosis is implicated in chondrocytes during the osteoarthritis (OA) progression with currently unknown mechanism(s). In this study we utilized a flow fluid shear stress (FFSS) model in cultured chondrocytes and a unilateral anterior crossbite (UAC) animal model. We found that both FFSS and UAC actively induced endoplasmic reticulum stress (ERS) in the temporomandibular joints (TMJ) chondrocytes, as demonstrated by dramatic increases in expression of HSPA5, p-EIF2AK3, p-ERN1 and ATF6. Interestingly, both FFSS and UAC activated not only pro-death p-EIF2AK3-mediated ERS-apoptosis programs but also pro-survival p-ERN1-mediated autophagic flux in chondrocytes. Data from FFSS demonstrated that MTORC1, a downstream of p-ERN1, suppressed autophagy but promoted p-EIF2AK3 mediated ERS-apoptosis. Data from UAC model demonstrated that at early stage both the p-ERN1 and p-EIF2AK3 were activated and MTORC1 was inhibited in TMJ chondrocytes. At late stage, MTORC1-p-EIF2AK3-mediated ERS apoptosis were predominant, while p-ERN1 and autophagic flux were inhibited. Inhibition of MTORC1 by TMJ local injection of rapamycin in rats or inducible ablation of MTORC1 expression selectively in chondrocytes in mice promoted chondrocyte autophagy and suppressed apoptosis, and reduced TMJ cartilage loss induced by UAC. In contrast, MTORC1 activation by TMJ local administration of MHY1485 or genetic deletion of Tsc1, an upstream MTORC1 suppressor, resulted in opposite effects. Collectively, our results establish that aberrant mechanical loading causes cartilage degeneration by activating, at least in part, the MTORC1 signaling which modulates the autophagy and apoptosis programs in TMJ chondrocytes. Thus, inhibition of MTORC1 provides a novel therapeutic strategy for prevention and treatment of OA.Abbreviations : ACTB: actin beta; ATF6: activating transcription factor 6; BECN1: beclin 1; BFL: bafilomycin A1; CASP12: caspase 12; CASP3: caspase 3; DAPI: 4',6-diamidino-2-phenylindole; DDIT3: DNA-damage inducible transcript 3; EIF2AK3/PERK: eukaryotic translation initiation factor 2 alpha kinase 3; ER: endoplasmic reticulum; ERS: endoplasmic reticulum stress; ERN1/IRE1: endoplasmic reticulum to nucleus signaling 1; FFSS: flow fluid shear stress; HSPA5/GRP78/BiP: heat shock protein 5; LAMP2: lysosome-associated membrane protein 2; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MTOR: mechanistic target of rapamycin kinase; MTORC1: mechanistic target of rapamycin complex 1; OA: osteoarthritis; PRKAA1/2/AMPK1/2: protein kinase, AMP-activated, alpha 1/2 catalytic subunit; RPS6: ribosomal protein S6; Rapa: rapamycin; SQSTM1/p62: sequestosome 1; TEM: transmission electron microscopy; TG: thapsigargin; TMJ: temporomandibular joints; TSC1/2: tuberous sclerosis complex 1/2; UAC: unilateral anterior crossbite; UPR: unfolded protein response; XBP1: x-box binding protein 1.

4.
Food Chem ; 308: 125576, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31648092

RESUMO

This study investigated the effects of cold storage at different temperatures (4, -0.5, -3, and -20 °C) on protein degradation and its relationship to structural changes of black carp muscle. At -0.5 and 4 °C, major structural changes occurred, including the formation of gaps between myofibers and myofibrils, breakage of myofibrils and myofibers, and degradation of sarcoplasmic reticulum. Gel-based proteomic analysis showed that these structural changes were accompanied by degradation of a series of myofibrillar proteins, including titin, nebulin, troponin, myosin, myomesin, myosin-binding protein, and α-actinin. Loss of extractable gelatinolytic and caseinolytic protease activities was also observed. At -3 and -20 °C, formation of ice crystals was the most noticeable change. The major proteins were degraded at different locations in the black carp muscle, and gelatinolytic and caseinolytic proteases appear to contribute to the degradation of those proteins.


Assuntos
Carpas/metabolismo , Actinina/metabolismo , Animais , Proteínas de Transporte , Temperatura Baixa , Conectina/metabolismo , Cyprinidae/metabolismo , Proteínas Musculares/metabolismo , Miofibrilas/metabolismo , Miosinas/metabolismo , Proteólise , Proteômica
5.
Arch Oral Biol ; 109: 104588, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31669922

RESUMO

OBJECTIVE: Dental occlusion are frequently changed in clinic. Molecular responses in jaw muscles to aberrant dental occlusion are changes are attractive, yet remain are obscure. DESIGN: Unilateral anterior crossbite (UAC) prostheses were applied to Sprague-Dawley rats and then ceased after two weeks to detect the reactions of the masseter, a representative jaw elevator, and the lateral pterygoid muscle (LPM), a representative jaw depressor. RESULTS: Two weeks of UAC elicited mild injury of the two muscles. Myogenesis and protective reactions were detected as increases in αB-crystallin expression in the masseter after 3 days and in the LPM after 2 weeks, and increases in desmin expression in both muscles after 2 weeks. A switch in fibre types from IIb to IIx occurred in the LPM but not in the masseter. Inflammatory responses, shown by the infiltration of inflammatory cells and increases in TNF-α mRNA expression, and fibrosis responses, shown by increased mRNA expression of Type I and III collagens, appeared very mild in the two muscles. These responses were partially recovered by the cessation of UAC. During the whole process, no obvious changes were observed in mitochondrial function, as indicated by the levels of proliferator-activated receptor γ coactivator 1α, mitofusin-2 and voltage-dependent anion channel. CONCLUSIONS: UAC causes injury and very limited inflammatory and fibrosis adaption in the masseter and LPM. Both muscles respond with myogenesis and protective activity. The LPM responds also with muscle fibre isoform alternations. These alterations were partially recovered by the cessation of dental stimulation at an early stage.


Assuntos
Implantes Dentários/efeitos adversos , Má Oclusão , Músculo Masseter/fisiopatologia , Músculos Pterigoides/fisiopatologia , Animais , Fibrose , Inflamação , Arcada Osseodentária , Músculo Masseter/lesões , Fibras Musculares Esqueléticas , Músculos Pterigoides/lesões , Ratos , Ratos Sprague-Dawley
6.
Bone ; 130: 115123, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31678498

RESUMO

Oestrogen and hypoxia inducible factor-2α (HIF2α) are key regulators in the pathogenesis of osteoarthritis (OA). However, the cellular interaction between oestrogen and HIF2α in articular cartilage during OA process remains unknown. Our previous study has revealed that high-physiological level of oestrogen aggravates the degradation of condylar cartilage in the early stage of temporomandibular joint osteoarthritis (TMJ OA). Here, we hypothesize that HIF2α involves the effect of oestrogen on mandibular condylar cartilage in the progression of TMJ OA. Our experiment in vivo found that the degeneration of condylar cartilage caused by unilateral anterior crossbite (UAC) model, characterized by obvious degenerative morphology, loss of cartilage extracellular matrix, up-regulation of TNF-α, HIF2α and its' down-stream OA-related cytokines (MMP-13, VEGF and Col X), could be alleviated by lack of oestrogen while aggravated by high level of oestrogen in rats. Meanwhile, our in vitro study found that 17ß-estradiol stimulation resulted in the loss of extracellular matrix, increased expression of TNF-α, IL-1, HIF2α and its' down-stream OA-related cytokines (MMP-13, VEGF and Col X) in primary condylar chondrocytes via oestrogen receptor beta (ERß), which could be reversed by ER antagonist, selective estrogen receptor modulators (SERMs) and HIF2α translation inhibitor. Our results reveal that high level of oestrogen can aggravate the degenerative changes of mandibular condylar cartilage, while lack of oestrogen can alleviate it via oestrogen-ERß-HIF2α pathway during TMJ OA progression.

7.
Chem Sci ; 10(39): 9140-9151, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31827756

RESUMO

The activities of biomolecules are affected by the proton concentrations at biological membranes. Here, we succeeded in evaluating the interface proton concentration (-log[H+] defined as pH') of cardiolipin (CL)-enriched membrane models of the inner mitochondrial membrane (IMM) using a spiro-rhodamine-glucose molecule (RHG). According to fluorescence microscopy and 1H-NMR studies, RHG interacted with the Stern layer of the membrane. The acid/base equilibrium of RHG between its protonated open form (o-RHG) and deprotonated closed spiro-form (c-RHG) at the membrane interface was monitored with UV-vis absorption and fluorescence spectra. The interface pH' of 25% cardiolipin (CL)-containing large unilamellar vesicles (LUVs), which possess similar lipid properties to those of the IMM, was estimated to be ∼3.9, when the bulk pH was similar to the mitochondrial intermembrane space pH (6.8). However, for the membranes containing mono-anionic lipids, the interface pH' was estimated to be ∼5.3 at bulk pH 6.8, indicating that the local negative charges of the lipid headgroups in the lipid membranes are responsible for the deviation of the interface pH' from the bulk pH. The peroxidase activity of cyt c increased 5-7 fold upon lowering the pH to 3.9-4.3 or adding CL-containing (10-25% of total lipids) LUVs compared to that at bulk pH 6.8, indicating that the pH' decrease at the IMM interface from the bulk pH enhances the peroxidase activity of cyt c. The peroxidase activity of cyt c at the membrane interface of tetraoleoyl CL (TOCL)-enriched (50% of total lipids) LUVs was higher than that estimated from the interface pH', while the peroxidase activity was similar to that estimated from the interface pH' for tetramyristoyl CL (TMCL)-enriched LUVs, supporting the hypothesis that when interacting with TOCL (not TMCL), cyt c opens the heme crevice to substrates. The present simple methodology allows us to estimate the interface proton concentrations of complex biological membranes.

8.
Biochim Biophys Acta Proteins Proteom ; 1867(11): 140265, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31437585

RESUMO

Many c-type cytochromes (cyts) can form domain-swapped oligomers. The positively charged Hydrogenobacter thermophilus (HT) cytochrome (cyt) c552 forms domain-swapped oligomers during expression in the Escherichia coli (E. coli) expression system, but the factors influencing the oligomerization remain unrevealed. Here, we found that the dimer of the negatively charged Shewanella violacea (SV) cyt c5 exhibits a domain-swapped structure, in which the N-terminal helix is exchanged between protomers, similar to the structures of the HT cyt c552 and Pseudomonas aeruginosa (PA) cyt c551 domain-swapped dimers. Positively charged horse cyt c and HT cyt c552 domain swapped during expression in E. coli, whereas negatively charged PA cyt c551 and SV cyt c5 did not. Oligomers were formed during expression in E. coli for HT cyt c552 attached to either a co- or post-translational signal peptide for transportation through the cytoplasm membrane, but not for PA cyt c551 attached to either signal peptide. HT cyt c552 formed oligomers in E. coli in the presence and absence of rare codons. More oligomers were obtained from the in vitro folding of horse cyt c and HT cyt c552 by the addition of negatively charged liposomes during folding, whereas the amount of oligomers for the in vitro folding of PA cyt c551 and SV cyt c5 did not change significantly by the addition. These results indicate that the protein surface charge affects the oligomerization of c-type cyts in cells; positively charged c-type cyts assemble on a negatively charged membrane, inducing formation of domain-swapped oligomers during folding.


Assuntos
Proteínas de Bactérias/química , Grupo dos Citocromos c/química , Multimerização Proteica , Pseudomonas aeruginosa/enzimologia , Shewanella/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Grupo dos Citocromos c/genética , Grupo dos Citocromos c/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Domínios Proteicos , Pseudomonas aeruginosa/genética , Shewanella/genética , Propriedades de Superfície
9.
Int J Mol Sci ; 20(15)2019 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-31382618

RESUMO

The temporomandibular joint (TMJ), which is biomechanically related to dental occlusion, is often insulted by osteoarthritis (OA). This study was conducted to clarify the relationship between Indian hedgehog (Ihh) and parathyroid hormone receptor 1 (PTH1R) signaling in modulating the enhanced chondrocyte terminal differentiation in dental stimulated TMJ osteoarthritic cartilage. A gain- and loss-of-function strategy was used in an in vitro model in which fluid flow shear stress (FFSS) was applied, and in an in vivo model in which the unilateral anterior cross-bite (UAC) stimulation was adopted. Ihh and PTH1R signaling was modulated through treating the isolated chondrocytes with inhibitor/activator and via deleting Smoothened (Smo) and/or Pth1r genes in mice with the promoter gene of type 2 collagen (Col2-CreER) in the tamoxifen-inducible pattern. We found that both FFSS and UAC stimulation promoted the deep zone chondrocytes to undergo terminal differentiation, while cells in the superficial zone were robust. We demonstrated that the terminal differentiation process in deep zone chondrocytes promoted by FFSS and UAC was mediated by the enhanced Ihh signaling and declined PTH1R expression. The FFSS-promoted terminal differentiation was suppressed by administration of the Ihh inhibitor or PTH1R activator. The UAC-promoted chondrocytes terminal differentiation and OA-like lesions were rescued in Smo knockout, but were enhanced in Pth1r knockout mice. Importantly, the relieving effect of Smo knockout mice was attenuated when Pth1r knockout was also applied. Our data suggest a chondrocyte protective effect of suppressing Ihh signaling in TMJ OA cartilage which is dependent on PTH1R signaling.


Assuntos
Proteínas Hedgehog/genética , Osteoartrite/genética , Receptor Tipo 1 de Hormônio Paratireóideo/genética , Receptor Smoothened/genética , Animais , Cartilagem Articular/crescimento & desenvolvimento , Cartilagem Articular/metabolismo , Diferenciação Celular/genética , Condrócitos/metabolismo , Condrócitos/patologia , Condrogênese/genética , Colágeno Tipo II/genética , Oclusão Dentária , Humanos , Camundongos , Camundongos Knockout , Osteoartrite/patologia , Transdução de Sinais/genética , Estresse Mecânico , Articulação Temporomandibular/crescimento & desenvolvimento , Articulação Temporomandibular/metabolismo
10.
Theranostics ; 9(15): 4265-4286, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31285761

RESUMO

Periodontal ligament stem cells (PDLSCs) can repair alveolar bone defects in periodontitis in a microenvironment context-dependent manner. This study aimed to determine whether different extracellular matrices (ECMs) exert diverse effects on osteogenic differentiation of PDLSCs and accurately control alveolar bone defect repair. Methods: The characteristics of PDLSCs and bone marrow mesenchymal stem cells (BMSCs) with respect to surface markers and multi-differentiation ability were determined. Then, we prepared periodontal ligament cells (PDLCs)-derived and bone marrow cells (BMCs)-derived ECMs (P-ECM and B-ECM) and the related decellularized ECMs (dECMs). Transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), and protein mass spectrometry were used to distinguish the ECMs. The expression of Type IV collagen A2 (COL4A2) in the ECMs was inhibited by siRNA or activated by lentiviral transduction of relevant cells. The stemness, proliferation, and differentiation of PDLSCs were determined in vitro in different dECMs. For the in vivo analysis, different dECMs under the regulation of COL4A2 mixed with PDLSCs and Bio-Oss bone powder were subcutaneously implanted into immunocompromised mice or in defects in rat alveolar bone. The repair effects were identified by histological or immunohistochemical staining and micro-CT. Results: B-dECM exhibited more compact fibers than P-dECM, as revealed by TEM, SEM, and AFM. Protein mass spectrometry showed that COL4A2 was significantly increased in B-dECM compared with P-dECM. PDLSCs displayed stronger proliferation, stemness, and osteogenic differentiation ability when cultured on B-dECM than P-dECM. Interestingly, B-dECM enhanced the osteogenic differentiation of PDLSCs to a greater extent than P-dECM both in vitro and in vivo, whereas downregulation of COL4A2 in B-dECM showed the opposite results. Furthermore, the classical Wnt/ß-catenin pathway was found to play an important role in the negative regulation of osteogenesis through COL4A2, confirmed by experiments with the Wnt inhibitor DKK-1 and the Wnt activator Wnt3a. Conclusion: These findings indicate that COL4A2 in the ECM promotes osteogenic differentiation of PDLSCs through negative regulation of the Wnt/ß-catenin pathway, which can be used as a potential therapeutic strategy to repair bone defects.

11.
Oral Dis ; 25(7): 1759-1768, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31357246

RESUMO

OBJECTIVES: To detect whether early growth response 1 (EGR1) in peripheral blood leucocytes (PBLs) indicates temporomandibular joint (TMJ) osteoarthritis (OA) lesions. MATERIALS AND METHODS: Egr1 mRNA expression levels in PBLs were detected in eight malocclusion patients without temporomandibular disorder (TMD) signs and 16 malocclusion patients with clinical TMD signs with (eight) or without (eight) imaging signs of TMJ OA. Twelve 6-week-old rats were randomized to a control group and a unilateral anterior crossbite (UAC) group and were sampled at 4 weeks. The Egr1 mRNA expression levels in PBLs and protein expression levels in different orofacial tissues were measured. RESULTS: Patients with TMD signs with/without TMJ OA diagnosis showed lower Egr1 mRNA expression levels in PBLs than patients without TMD signs. The lower Egr1 mRNA expression was also found in the PBLs of UAC rats, which were induced to exhibit early histo-morphological signs of TMJ OA lesions. In subchondral bone of UAC rats, EGR1 protein expression was decreased, co-localization of EGR1 with osterix or dentin matrix protein-1 was identified, and the number of EGR1 and osterix double-positive cells was reduced (all p < .05). CONCLUSION: Egr1 reduction in PBLs potentially indicates subchondral bone OA lesions at an early stage.


Assuntos
Cartilagem Articular , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Côndilo Mandibular , Osteoartrite , Transtornos da Articulação Temporomandibular/etiologia , Animais , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Proteína 1 de Resposta de Crescimento Precoce/genética , Má Oclusão/complicações , RNA Mensageiro , Distribuição Aleatória , Ratos , Articulação Temporomandibular , Transtornos da Articulação Temporomandibular/metabolismo , Tomografia Computadorizada por Raios X , Fatores de Transcrição/análise
12.
Oral Dis ; 25(6): 1589-1599, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31132303

RESUMO

OBJECTIVE: We aimed to develop a mouse model predominating in a proliferative response in the articular cartilage of the temporomandibular joints. MATERIALS AND METHODS: Bilateral anterior elevation of occlusion was developed by installing metal tubes onto the incisors of mice with edge-to-edge relation to prevent tooth wear, leading to an increase in the vertical height of the dental occlusion with time. Morphological changes and expression changes in Cyclin D1, Aggrecan, and type II and type X collagen in the mandibular condylar cartilage were detected. In addition, cells were isolated from the mandibular condylar cartilage and exposed to cyclic tensile strain (CTS). RESULTS: Compared with age-matched controls, the tooth length was longer at 3 weeks, 7 weeks, and 11 weeks in BAE mice (p < 0.05), with increased condylar cartilage thickness, matrix amount, and cell number (p < 0.05). Compared with the deep zone cells, CTS stimulated the superficial zone cells to express a higher level of proliferating cell nuclear antigen, Cyclin D1, Aggrecan, and type II collagen but a lower level of type X collagen and alkaline phosphatase. CONCLUSION: Bilateral anterior elevation stimulated the proliferative response in the mandibular condylar cartilage, offering a new therapeutic strategy for cartilage degeneration.


Assuntos
Cartilagem Articular , Implantes Dentários , Côndilo Mandibular , Animais , Proliferação de Células , Condrócitos , Camundongos
13.
J Oral Rehabil ; 46(9): 820-827, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31046158

RESUMO

Biomarkers of temporomandibular joint (TMJ) osteoarthritis (OA) remain unknown. The objective was to detect whether molecular biomarkers from peripheral blood leucocytes (PBLs) engage in TMJ OA lesions. Thirty-four six-week-old Sprague Dawley rats were used. The top upregulated gene ontology categories and gene-fold changes in PBLs were detected by a microarray analysis comparing rats that received 20-week unilateral anterior crossbite (UAC) treatment with age-matched controls (n = 4). Twenty weeks of UAC treatment had been reported to induce TMJ OA-like lesions. The other twenty-four rats were randomly placed in the UAC and control groups at 12- and 20-week time points (n = 6). The mRNA expression levels of the selected biomarkers derived from the microarray analysis and their protein expression in the alveolar bone and TMJ were detected. The microarray analysis indicated that the three most highly involved genes in PBLs were Egr1, Ephx1 and Il10, which were confirmed by real-time PCR detection. The increased protein expression levels of the three detected molecules were demonstrated in cartilage and subchondral bone (P < 0.05), and increased levels of EPHX1 were reported in discs (P < 0.05); however, increased levels were not present in the alveolar bone. Immunohistochemistry revealed the increased distribution of EGR1-positive, EXPH1-positive and IL10-positive cells predominantly in the osteochondral interface, with EXPH1 also present in TMJ discs. In conclusion, the increased mRNA expression of Egr1, Ephx1 and Il10 in PBLs may serve as potential biomarkers for developed osteoarthritic lesions relating to osteochondral interface hardness changes induced by dental biomechanical stimulation.


Assuntos
Cartilagem Articular , Transtornos da Articulação Temporomandibular , Animais , Côndilo Mandibular , Ratos , Ratos Sprague-Dawley , Articulação Temporomandibular
14.
Int J Comput Assist Radiol Surg ; 14(6): 1069-1077, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30968351

RESUMO

PURPOSE: Efficient image-based catheter localization in 3D US during cardiac interventions is highly desired, since it facilitates the operation procedure, reduces the patient risk and improves the outcome. Current image-based catheter localization methods are not efficient or accurate enough for real clinical use. METHODS: We propose a catheter localization method for 3D cardiac ultrasound (US). The catheter candidate voxels are first pre-selected by the Frangi vesselness filter with adaptive thresholding, after which a triplanar-based ConvNet is applied to classify the remaining voxels as catheter or not. We propose a Share-ConvNet for 3D US, which reduces the computation complexity by sharing a single ConvNet for all orthogonal slices. To boost the performance of ConvNet, we also employ two-stage training with weighted cross-entropy. Using the classified voxels, the catheter is localized by a model fitting algorithm. RESULTS: To validate our method, we have collected challenging ex vivo datasets. Extensive experiments show that the proposed method outperforms state-of-the-art methods and can localize the catheter with an average error of 2.1 mm in around 10 s per volume. CONCLUSION: Our method can automatically localize the cardiac catheter in challenging 3D cardiac US images. The efficiency and accuracy localization of the proposed method are considered promising for catheter detection and localization during clinical interventions.


Assuntos
Cateteres , Imagem Tridimensional/métodos , Ultrassonografia/métodos , Algoritmos , Humanos
15.
Am J Chin Med ; 47(3): 577-594, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30974967

RESUMO

Thymoquinone (TQ) is a main aromatic component of Nigella sativa L. seeds or Agastache rugosa (Fisch. & C.A.Mey.) Kuntze. The protective mechanism of TQ against acute liver injury induced by acetaminophen (APAP), however, remains unclear. We aimed to investigated the hepato-protective mechanism of TQ on the development of APAP-induced acute liver injury. Male kunming mice were pretreated with TQ or N-acetylcysteine (NAC) before a single APAP injection. Human Chang liver cells were incubated with TQ, SP600125 or AICAR in presence of APAP for 24 h. TQ pretreatment reduced levels of serum aminotransferases and increased hepatic glutathione and glutathione peroxidase activities via inhibiting CYP2E1 expression. TQ inhibited JNK, ERK and P38 phosphorylation induced by APAP. Meanwhile, TQ inhibited PI3K/mTOR signaling activation and activated AMPK phosphorylation. Moreover, TQ prevented APAP-induced hepatocytes apoptosis regulated by Bcl-2 and Bax. Furthermore, TQ inhibited STAT3 phosphorylation on APAP-induced acute liver injury. In addition, TQ significantly inhibited P2X7R protein expression and IL-1 ß release. APAP-enhanced JNK phosphorylation and APAP-suppressed AMPK phosphorylation were also observed in Chang liver cells, and these changes were recovered by pretreatment with TQ, SP600125 and AICAR. Our findings suggest that TQ may actively prevent APAP-induced acute liver injury, and the effect may be mediated by JNK and AMPK signaling pathways.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Acetaminofen/administração & dosagem , Acetaminofen/efeitos adversos , Benzoquinonas/farmacologia , Benzoquinonas/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Overdose de Drogas/complicações , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fitoterapia , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Modelos Animais de Doenças , Hepatócitos/efeitos dos fármacos , Humanos , Inflamação , Masculino , Camundongos
16.
Arch Oral Biol ; 101: 108-121, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30927660

RESUMO

OBJECTIVE: Chondrocyte apoptosis is a pathological manifestation of osteoarthritis. The goal of this report was to explore the role of nitric oxide in chondrocyte apoptosis in osteoarthritic mandibular condylar cartilage. DESIGN: This study used our reported experimental unilateral anterior crossbite in vivo rat model and chondrocyte fluid flow shear stress in vitro model. In the in vivo model, apoptosis in the mandibular condylar cartilage was assessed by detection of the TUNEL-positive cells, the expression levels of inducible nitric oxide synthase (iNOS), caspase-9, and caspase-3. In the in vitro model, mitochondrial injury was evaluated, the nitric oxide and superoxide dismutase (SOD) production levels were measured, and the cytochrome C (Cyt C) expression level was detected. The expression levels of apoptosis-related proteins B cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase-3, and poly-ADP-ribose polymerase 1 (PARP1) were analyzed in both in vivo and in vitro models. The effects of iNOS inhibitor on chondrocyte apoptosis were also investigated. RESULTS: The data indicated that the unilateral anterior crossbite induced cartilage degeneration with enhanced cell apoptosis and stimulated the expression of caspase-3/-9 and iNOS. The fluid flow shear stress upregulated the expression of iNOS, SOD, and nitric oxide, reduced mitochondrial membrane potential, and promoted Cyt C to enter the cytoplasm. All of these changes were reversed by iNOS inhibitors. CONCLUSION: The abnormal occlusion stimulated mitochondrial damage and apoptosis of the chondrocytes in the mandibular condylar cartilage mediated by nitric oxide. Inhibiting nitric oxide production could be a therapeutic strategy.


Assuntos
Apoptose , Condrócitos/citologia , Oclusão Dentária , Côndilo Mandibular/citologia , Mitocôndrias/efeitos dos fármacos , Óxido Nítrico/efeitos adversos , Animais , Cartilagem Articular/patologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Citocromos c/metabolismo , Potencial da Membrana Mitocondrial , Mitocôndrias/patologia , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Superóxido Dismutase/metabolismo
17.
J Med Imaging (Bellingham) ; 6(1): 015001, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30662926

RESUMO

Ultrasound (US) has been increasingly used during interventions, such as cardiac catheterization. To accurately identify the catheter inside US images, extra training for physicians and sonographers is needed. As a consequence, automated segmentation of the catheter in US images and optimized presentation viewing to the physician can be beneficial to accelerate the efficiency and safety of interventions and improve their outcome. For cardiac catheterization, a three-dimensional (3-D) US image is potentially attractive because of no radiation modality and richer spatial information. However, due to a limited spatial resolution of 3-D cardiac US and complex anatomical structures inside the heart, image-based catheter segmentation is challenging. We propose a cardiac catheter segmentation method in 3-D US data through image processing techniques. Our method first applies a voxel-based classification through newly designed multiscale and multidefinition features, which provide a robust catheter voxel segmentation in 3-D US. Second, a modified catheter model fitting is applied to segment the curved catheter in 3-D US images. The proposed method is validated with extensive experiments, using different in-vitro, ex-vivo, and in-vivo datasets. The proposed method can segment the catheter within an average tip-point error that is smaller than the catheter diameter (1.9 mm) in the volumetric images. Based on automated catheter segmentation and combined with optimal viewing, physicians do not have to interpret US images and can focus on the procedure itself to improve the quality of cardiac intervention.

18.
J Bone Miner Res ; 34(4): 726-738, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30496623

RESUMO

Traumatic joint injuries produce osteoarthritic cartilage manifesting accelerated chondrocyte terminal differentiation and matrix degradation via unknown cellular and molecular mechanisms. Here we report the ability of biomechanical stress to increase expression of the calcium-sensing receptor (CaSR), a pivotal driver of chondrocyte terminal differentiation, in cultured chondrogenic cells subjected to fluid flow shear stress (FFSS) and in chondrocytes of rodent temporomandibular joint (TMJ) cartilage subjected to unilateral anterior cross-bite (UAC). In cultured ATDC5 cells or TMJ chondrocytes, FFSS induced Ca2+ loading and CaSR localization in endoplasmic reticulum (ER), casually accelerating cell differentiation that could be abrogated by emptying ER Ca2+ stores or CaSR knockdown. Likewise, acute chondrocyte-specific Casr knockout (KO) prevented the UAC-induced acceleration of chondrocyte terminal differentiation and matrix degradation in TMJ cartilage in mice. More importantly, local injections of CaSR antagonist, NPS2143, replicated the effects of Casr KO in preventing the development of osteoarthritic phenotypes in TMJ cartilage of the UAC-treated rats. Our study revealed a novel pathological action of CaSR in development of osteoarthritic cartilage due to aberrant mechanical stimuli and supports a therapeutic potential of calcilytics in preventing osteoarthritis in temporomandibular joints by targeting the CaSR. © 2018 American Society for Bone and Mineral Research.

19.
Arch Oral Biol ; 98: 17-25, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30419485

RESUMO

OBJECTIVE: To investigate the changes in insulin-like growth factor-1 (IGF-1) expression levels in the degenerative mandibular condylar cartilage. DESIGN: Thirty-six rats were divided into the unilateral anterior crossbite and control groups. The expression levels of IGF-1; IGF-1 receptor (IGF-1R); IGF-binding protein-3 and -5 (IGFBP-3 and -5); proliferating cell nuclear antigen (PCNA); aggrecan; type-I, -II, -VI, and -X collagen; tissue inhibitor of metalloproteinases-1 and -3 (TIMP-1 and -3); metalloproteinases of matrix metalloproteinases-3 and-13 (MMP-3 and -13); a disintegrin and metalloproteinase thrombospondin-4 and -5 (ADAMTS-4 and -5); alkaline phosphatase (ALP); ß-glucuronidase; and N-acetyl-ß-glucosaminidase in the mandibular condylar cartilage were assessed. RESULTS: The protein expression levels of IGF-1and IGF-1R were increased from week 4 in the unilateral anterior crossbite group. The mRNA expression level of IGFBP-3 and -5 was upregulated from week 4 and week 2, respectively; that of IGFBP-3 was downregulated at week 8; and that of PCNA, type-II collagen, type-X collagen, aggrecan, TIMP-1, and TIMP-3 was downregulated, whereas that of MMP-3, MMP-13, ADAMTS-4, ADAMTS-5, ß-glucuronidase, and N-acetyl-ß-glucosaminidase were upregulated from week 2. The positive area size of type-I collagen was increased and that of type VI collagen was decreased from week 2. The positive area size of type X collagen was increased at week 2 but decreased at week 8. The percentage of ALP-positive cells was increased from week 4. CONCLUSIONS: Unilateral anterior crossbite stimulated the multifarious expression of IGF-1 and IGFBP, which may be linked to chondrocyte proliferation and differentiation in the mandibular condylar cartilage that showed progressive degeneration.


Assuntos
Doenças das Cartilagens/etiologia , Cartilagem Articular/patologia , Fator de Crescimento Insulin-Like I/metabolismo , Má Oclusão/complicações , Côndilo Mandibular/metabolismo , Côndilo Mandibular/patologia , Transtornos da Articulação Temporomandibular/etiologia , Proteína ADAMTS4/metabolismo , Proteína ADAMTS5/metabolismo , Agrecanas/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Condrócitos/patologia , Colágeno/metabolismo , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Glucuronidase/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor IGF Tipo 1/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-3/metabolismo , Regulação para Cima
20.
J Oral Rehabil ; 46(4): 340-348, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30556174

RESUMO

BACKGROUND: The temporomandibular joint (TMJ) disc plays a role in joint movement and in load absorbance and distribution. An experimental unilateral anterior crossbite (UAC) prosthesis induces mandibular condylar cartilage degeneration in rats. However, the changes in the articular disc are still unknown. OBJECTIVE: To describe changes in the TMJ discs of UAC rats. METHODS: The discs of fifty-four Sprague-Dawley rats, equally distributed into a UAC group and an age-matched sham-operated control group at 4, 12 and 20 weeks (n = 9), were evaluated by gross and histomorphological observation and by detection at the mRNA or protein expression levels of the markers related to the matrix elements. RESULTS: No macro- or micro-morphological differences were observed between groups. However, there were catabolic degradative changes at the molecular level in the UAC group, showing a significant reduction in the mRNA and/or protein expression levels of many molecules. The reduction became worse with time (P < 0.05). The reduced molecules included: (a) those related to the extracellular matrix, such as type I collagen, decorin and fibromodulin; (b) those related to chondrogenesis, such as type II collagen and aggrecan; and (c) those related to osteogenesis, such as alkaline phosphatase and runt-related transcription factor 2. The mRNA expression of vascular endothelial growth factor did not change. In contrast, fibronectin, which can promote wound healing, and its N-terminal fragment, which can induce cartilage degradation, were accumulated (P < 0.05). CONCLUSION: TMJ discs were stimulated to catabolic changes by the aberrant dental occlusion and seemed to go to inanimate with time.


Assuntos
Má Oclusão/metabolismo , Má Oclusão/patologia , Côndilo Mandibular/metabolismo , Côndilo Mandibular/patologia , Disco da Articulação Temporomandibular/metabolismo , Disco da Articulação Temporomandibular/patologia , Animais , Cartilagem Articular/patologia , Condrócitos/patologia , Oclusão Dentária , Modelos Animais de Doenças , Feminino , Má Oclusão/complicações , Fenômenos Mecânicos , Ratos , Ratos Sprague-Dawley
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