Connective Tissue Research最新文献

{"title":"Pigment epithelium-derived factor modulates periodontal homeostasis in mice and induces osteogenic differentiation of human periodontal ligament fibroblasts.","authors":"Cheng Xu,&nbsp;Yu Du,&nbsp;Jun Tian,&nbsp;Chang Liu,&nbsp;Yihua Huang,&nbsp;Ti Zhou,&nbsp;Yang Ning","doi":"10.1080/03008207.2021.2025224","DOIUrl":"https://doi.org/10.1080/03008207.2021.2025224","url":null,"abstract":"<p><strong>Aim: </strong>The aim of this study was to investigate the influence of pigment epithelium-derived factor (PEDF) on periodontal homeostasis in mice and the osteogenic differentiation of human periodontal ligament fibroblasts (PDLFs).</p><p><strong>Materials and methods: </strong>Micro-computed tomography and histology were performed to compare the alveolar bone volume, density, and bone-related markers between PEDF-deficient (PEDF^-/-) and wild-type (WT) mice. Furthermore, after recombinant human PEDF treatment, the PDLF viability and osteogenic differentiation were examined using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay, alkaline phosphatase (ALP) activity assay, Von Kossa staining, Alizarin red staining, real-time quantitative polymerase chain reaction (qRT-PCR), and immunoblotting.</p><p><strong>Results: </strong>The alveolar bone volume and density of PEDF^-/- mice were significantly lower than those of the WT mice. Higher receptor activator for nuclear factor-κB ligand (RANKL) expression and lower osteoprotegerin (OPG) expression levels were observed in the PEDF^-/- group. Moreover, PEDF treatment did not affect the PDLF proliferation. PEDF dose-dependently improved mineral deposition. Compared with the control group, 250 ng/mL PEDF promoted OPG mRNA expression in PDLFs on Day 3 but inhibited RANKL, Wnt5a, GSK3b mRNA, and non-phosphorylated β-catenin protein expression. However, 250 ng/mL PEDF had no significant effect on the expression of Wnt3a. On Day 7, after culture with 250 ng/mL PEDF in osteogenic medium, the ALP and RUNX2 protein levels were upregulated. VEGF protein expression was reduced in a dose-dependent manner after PEDF stimulation. The PEDF protein expression increased as the osteogenic induction time increased.</p><p><strong>Conclusion: </strong>PEDF gene knockout suppresses periodontal homeostasis in mice, and PEDF treatment induces PDLF osteogenic differentiation <i>in vitro</i>.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39893214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oral mucosa equivalents, prevascularization approaches, and potential applications.","authors":"Daniela S Masson-Meyers, Luiz E Bertassoni, Lobat Tayebi","doi":"10.1080/03008207.2022.2035375","DOIUrl":"10.1080/03008207.2022.2035375","url":null,"abstract":"<p><strong>Background: </strong>Oral mucosa equivalents (OMEs) have been used as <i>in vitro</i> models (eg, for studies of human oral mucosa biology and pathology, toxicological and pharmacological tests of oral care products), and clinically to treat oral defects. However, the human oral mucosa is a highly vascularized tissue and implantation of large OMEs can fail due to a lack of vascularization. To develop equivalents that better resemble the human oral mucosa and increase the success of implantation to repair large-sized defects, efforts have been made to prevascularize these constructs.</p><p><strong>Purpose: </strong>The aim of this narrative review is to provide an overview of the human oral mucosa structure, common approaches for its reconstruction, and the development of OMEs, their prevascularization, and <i>in vitro</i> and clinical potential applications.</p><p><strong>Study selection: </strong>Articles on non-prevascularized and prevascularized OMEs were included, since the development and applications of non-prevascularized OMEs are a foundation for the design, fabrication, and optimization of prevascularized OMEs.</p><p><strong>Conclusions: </strong>Several studies have reported the development and <i>in vitro</i> and clinical applications of OMEs and only a few were found on prevascularized OMEs using different approaches of fabrication and incorporation of endothelial cells, indicating a lack of standardized protocols to obtain these equivalents. However, these studies have shown the feasibility of prevascularizing OMEs and their implantation in animal models resulted in enhanced integration and healing. Vascularization in tissue equivalents is still a challenge, and optimization of cell culture conditions, biomaterials, and fabrication techniques along with clinical studies is required.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9357199/pdf/nihms-1823920.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10131613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Axin2-lineage cells contribute to neonatal tendon regeneration.","authors":"B Walia,&nbsp;T M Li,&nbsp;G Crosio,&nbsp;A M Montero,&nbsp;A H Huang","doi":"10.1080/03008207.2022.2036732","DOIUrl":"https://doi.org/10.1080/03008207.2022.2036732","url":null,"abstract":"<p><strong>Purpose: </strong>Tendon injuries are a challenging clinical problem with few treatment options. Identifying the molecular regulators of tendon is required for the development of new therapies. While the Wnt pathway is critical for the maintenance and differentiation of many tissues, the role of Wnt signaling in tendon cell biology remains largely unexplored.</p><p><strong>Methods: </strong>The effects of Wnt activation were tested <i>in vitro</i> using neonatal tendon-derived cells cultured in 2D and 3D conditions. The inducible Axin2CreERT2 was then used to label Axin2+ cells <i>in vivo</i> and cells were traced during neonatal tendon regeneration.</p><p><strong>Results: </strong>We showed that activation of Wnt signaling results in proliferation of neonatal tendon cells. While tendon marker expression was inhibited by Wnt activation under 2D conditions, <i>Scx</i> expression was not affected under 3D uniaxial tension, suggesting that the microenvironment contextualizes tendon cell response to Wnt signaling. Using an <i>in vivo</i> model of neonatal tendon regeneration, we further showed that Wnt signaling cells comprise a subpopulation of tenocyte and epitenon cells that proliferate after injury and are recruited during regeneration.</p><p><strong>Discussion: </strong>Collectively, these studies suggest that Wnt signaling may play a role in tendon cell proliferation, differentiation, and regeneration.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9491382/pdf/nihms-1835287.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10134216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exercise-driven exacerbation of inflammation: contribution of animal models of rheumatoid arthritis and spondyloarthritis.","authors":"Susana Aideé González-Chávez,&nbsp;César Pacheco-Tena","doi":"10.1080/03008207.2022.2036734","DOIUrl":"https://doi.org/10.1080/03008207.2022.2036734","url":null,"abstract":"<p><strong>Purpose: </strong>To describe the observations of studies that have explored the effects of exercise on inflammation and tissue remodeling in animal models of inflammatory arthropathies including Rheumatoid Arthritis and Spondyloarthritis.</p><p><strong>Methods: </strong>A search was performed at Pubmed, Scopus and Web of Science databases from 2010 to 2021. The selected articles were classified into those who reported positive and negative effects of exercise, and the characteristics of their experimental designs, including the animal model, the study groups, the exercise intervention and the evaluation techniques, were detailed.</p><p><strong>Results: </strong>Thirteen original articles that met the selection criteria were included. The effects of exercise on the joint biology of mice with inflammatory arthritis were controversial. Although exercise benefits have been observed in some experimental designs, the majority of them have shown that exercise leads to exacerbation of inflammation, tissue remodeling, and processes associated with arthritis such as oxidative stress and hypoxia.</p><p><strong>Conclusion: </strong>Further research is necessary as the existing guidelines do not consider the negative effects of the exercise evidenced in animal models. The potential risks of exercise for patients should be considered.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39637061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IGF-1R/YAP signaling pathway is involved in collagen V-induced insulin biosynthesis and secretion in rat islet INS-1 cells.","authors":"Yingying Zhu,&nbsp;Shuaigao Chen,&nbsp;Weiwei Liu,&nbsp;Fanxing Xu,&nbsp;Jingyu Lu,&nbsp;Toshihiko Hayashi,&nbsp;Kazunori Mizuno,&nbsp;Shunji Hattori,&nbsp;Hitomi Fujisaki,&nbsp;Takashi Ikejima","doi":"10.1080/03008207.2021.2025225","DOIUrl":"https://doi.org/10.1080/03008207.2021.2025225","url":null,"abstract":"<p><strong>Purpose: </strong>Type V collagen (collagen V) is one of the important components of extracellular matrix (ECM) in pancreas. We previously reported that pre-coating collagen V on the culture dishes enhanced insulin production in INS-1 rat pancreatic β cells. In this study, we investigate the underlying mechanism.</p><p><strong>Results: </strong>Insulin biosynthesis and secretion are both increased in INS-1 cells cultured on collagen V-coated dishes, accompanied by the reduced nuclear translocation of Yes-associated protein (YAP), a transcriptional co-activator. YAP, the downstream effector of Hippo signaling pathway, plays an important role in the development and function of pancreas. Inhibition of YAP activation by verteporfin further up-regulates insulin biosynthesis and secretion. Silencing large tumor suppressor (LATS), a core component of Hippo pathway which inhibits activity of YAP by phosphorylation, by siRNA transfection inhibits both insulin biosynthesis and secretion. In the present study, the protein level of insulin-like growth factor 1 receptor (IGF-1 R), detected as the upstream molecule of YAP, is reduced in the INS-1 cells cultured on the dishes coated with collagen V. The silencing of IGF-1 R by siRNA transfection further enhances insulin biosynthesis and secretion. IGF-1 treatment reduces collagen V-induced up-regulation of insulin biosynthesis and secretion, accompanying the increased nuclear YAP.</p><p><strong>Conclusion: </strong>Inhibition of IGF-1 R/YAP signal pathway is involved in collagen V-induced insulin biosynthesis and secretion in INS-1 cells.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39896179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RHOA inhibits chondrogenic differentiation of mesenchymal stem cells in adolescent idiopathic scoliosis.","authors":"Mingyuan Yang,&nbsp;Kai Chen,&nbsp;Canglong Hou,&nbsp;Yilin Yang,&nbsp;Xiao Zhai,&nbsp;Kai Chen,&nbsp;Xianzhao Wei,&nbsp;Yushu Bai,&nbsp;Ming Li","doi":"10.1080/03008207.2021.2019247","DOIUrl":"https://doi.org/10.1080/03008207.2021.2019247","url":null,"abstract":"<p><strong>Purpose: </strong>The etiology of adolescent idiopathic scoliosis (AIS) remains unclear. The chondrogenic differentiation of mesenchymal stem cells (MSCs) is important in AIS, and the Ras homolog gene family member A (RHOA) is associated with chondrogenesis. The purpose of this study was to explore the effect of RHOA on the chondrogenic differentiation of MSCs in AIS.</p><p><strong>Methods: </strong>We isolated MSCs from patients with AIS (AIS MSCs) and individuals without AIS (control MSCs). The inhibitor Y27632 was used to inhibit the function of RHOA/ROCK signaling, and plasmid-based overexpression and siRNA-mediated knockdown were used to manipulate RHOA expression. CCK-8 was used to detect cell viability. The phosphorylation levels of LIMK1, MLC2 and cofilin were detected by Western blotting. The mRNA expression of aggrecan, SOX9, and COL2A1 were confirmed using RT-PCR. Immunofluorescence was used to analyze F-actin and collagen II. Alcian blue staining was performed to assess the secretion of glycosaminoglycans (GAGs).</p><p><strong>Results: </strong>We found that RHOA was significantly upregulated in AIS MSCs, and the phosphorylation levels of LIMK1, MLC2, and cofilin were increased. The mRNA expressions of aggrecan, SOX9, and COL2A1 were notably reduced in AIS MSCs. However, these effects were abolished by Y27632 treatment and RHOA knockdown in AIS MSCs. In addition, RHOA knockdown in AIS MSCs increased the content of collagen II and GAGs. RHOA overexpression in the control MSCs markedly activated the RHOA/ROCK signaling and decreased the expression of aggrecan, SOX9, and COL2A1, F-actin, and GAGs.</p><p><strong>Conclusion: </strong>RHOA regulates the chondrogenic differentiation ability of MSCs in AIS via the RHOA/ROCK signaling pathway and this regulation may involve SOX9.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39903177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructured collagen films for 3D corneal stroma modelling.","authors":"Juha Prittinen,&nbsp;Xin Zhou,&nbsp;Fouzia Bano,&nbsp;Ludvig Backman,&nbsp;Patrik Danielson","doi":"10.1080/03008207.2021.2007901","DOIUrl":"https://doi.org/10.1080/03008207.2021.2007901","url":null,"abstract":"<p><strong>Purpose/aim: </strong>Corneal injury is a major cause of impaired vision around the globe. The fine structure of the corneal stroma plays a pivotal role in the phenotype and behavior of the embedded cells during homeostasis and healing after trauma or infection. In order to study healing processes in the cornea, it is important to create culture systems that functionally mimic the natural environment.</p><p><strong>Materials and methods: </strong>Collagen solution was vitrified on top of a grated film to achieve thin collagen films with parallel microgrooves. Keratocytes (corneal stromal cells) were cultured on the films either as a single layer or as stacked layers of films and cells. SEM and F-actin staining were used to analyze the pattern transference onto the collagen and the cell orientation on the films. Cell viability was analyzed with MTS and live/dead staining. Keratocytes, fibroblasts, and myofibroblasts were cultured to study the pattern's effect on phenotype.</p><p><strong>Results: </strong>A microstructured collagen film-based culture system that guides keratocytes (stromal cells) to their native, layerwise perpendicular orientation in 3D and that can support fibroblasts and myofibroblasts was created. The films are thin and transparent enough to observe cells at least three layers deep. The cells maintain viability in 2D and 3D cultures and the films can support fibroblast and myofibroblast phenotypes.</p><p><strong>Conclusions: </strong>The films provide an easily reproducible stroma model that maintains high cell viability and improves the preservation of the keratocyte phenotype in keratocytes that are differentiated to fibroblasts.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39592528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative analysis of tendon histopathology using digital pathology in rat models with Achilles tendon injury.","authors":"Jae Hyeon Park,&nbsp;Sun G Chung,&nbsp;Ji-Young Jun,&nbsp;Jin-Ju Lee,&nbsp;Kyoungbun Lee","doi":"10.1080/03008207.2021.2011251","DOIUrl":"https://doi.org/10.1080/03008207.2021.2011251","url":null,"abstract":"<p><p>Although digital image analysis methods that quantify histopathologic features have emerged, no validated quantitative methods are available to evaluate tendon injury. This study aimed to propose and validate a quantitative analysis method to identify the histopathologic features of tendon injuries. The histopathologic features of two Achilles tendon injury models (a partial full-thickness defect model and a collagenase injection model) using Sprague-Dawley rats were evaluated by semiquantitative grading and a quantitative analysis method using a digital pathology software at weeks 1 and 4 after tendon injury (six tendons per group at each time point). The outcome variables between tendon injury models and between time points were compared, and the correlation between semiquantitative scores and the results of the quantitative analysis was investigated. The proposed analysis method quantified the severity of the histopathological features after tendon injury. Quantitative analysis differentiated the cell morphology between tendon injury models and time points better than semiquantitative scoring. The results from quantitative measurements correlated significantly with the semiquantitative scores. The proposed quantitative method can be effective in evaluating the histopathology of tendon injuries.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39777689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PDGF-AA promotes gap junction intercellular communication in chondrocytes via the PI3K/Akt pathway.","authors":"Siqun Xu,&nbsp;Yang Liu,&nbsp;Demao Zhang,&nbsp;Hongcan Huang,&nbsp;Jiachi Li,&nbsp;Jieya Wei,&nbsp;Yueyi Yang,&nbsp;Yujia Cui,&nbsp;Jing Xie,&nbsp;Xuedong Zhou","doi":"10.1080/03008207.2022.2036733","DOIUrl":"https://doi.org/10.1080/03008207.2022.2036733","url":null,"abstract":"<p><strong>Background: </strong>Gap junction intercellular communication (GJIC) plays an important role in cell growth, development and homeostasis. Connexin 43 (Cx43) is an important half-channel protein responsible for gap junction formation. Platelet-derived growth factor AA (PDGF-AA) regulates the proliferation, migration, metabolism, apoptosis and cell cycle of chondrocytes. However, the role of PDGF-AA in gap junction intercellular communication in chondrocytes is not fully understood. In the current study, we performed experiments to explore the effect of PDGF-AA on GJIC and its underlying biomechanical mechanism.</p><p><strong>Methods: </strong>qPCR was performed to determine the expression of PDGF, PDGFR and connexin family genes in chondrocytes and/or cartilage. A scrape loading/dye transfer assay was used to determine GJIC. Western blot analysis was applied to detect the expression of Cx43 and PI3K/Akt signaling pathway proteins. Immunofluorescence staining was utilized to examine protein distribution. Scanning electron microscopy was used to delineate the morphology of chondrocytes.</p><p><strong>Results: </strong>Expression of <i>PDGF-A</i> mRNA was highest among the PDGF family in chondrocytes and cartilage tissues. PDGF-AA promoted functional GJIC formation in chondrocytes by upregulating the expression of Cx43. Enhanced functional GJIC formation in chondrocytes induced by PDGF-AA occurred through the activation of PI3K/Akt signaling and its nuclear accumulation.</p><p><strong>Conclusion: </strong>For the first time, this study provides evidence demonstrating the role of PDGF-AA in cell-to-cell communication in chondrocytes through mediating Cx43 expression.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39913863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The potential role of mechanosensitive ion channels in substrate stiffness-regulated Ca²⁺ response in chondrocytes.","authors":"Genlai Du,&nbsp;Weiyi Chen,&nbsp;Li Li,&nbsp;Quanyou Zhang","doi":"10.1080/03008207.2021.2007902","DOIUrl":"https://doi.org/10.1080/03008207.2021.2007902","url":null,"abstract":"<p><strong>Purpose: </strong>The stiffness of the pericellular matrix (PCM) decreases in the most common degenerative joint disease, osteoarthritis (OA). This study was undertaken to explore the potential functional role of transient receptor potential vanilloid 4 (TRPV4), Piezo1, and Piezo2 in transducing different PCM stiffness in chondrocytes.</p><p><strong>Methods and results: </strong>Polydimethylsiloxane (PDMS) substrates with different stiffness (designated 197 kPa, 78 kPa, 54 kPa, or 2 kPa, respectively) were first prepared to simulate the decrease in stiffness of the PCM that chondrocytes encounter in osteoarthritic cartilage. Next, the TRPV4-, Piezo1-, or Piezo2-knockdown primary chondrocytes (designated TRPV4-KD, Piezo1-KD, or Piezo2-KD cells) were seeded onto these different PDMS substrates. Then, using a Ca²⁺-imaging system, substrate stiffness-regulated intracellular Ca²⁺ influx ([Ca²⁺]<i>_i</i>) in chondrocytes was examined to investigate the role of TRPV4, Piezo1, and Piezo2 in Ca²⁺ signaling in response to different stiffness. Results showed that the characteristics of intracellular [Ca²⁺]<i>_i</i> in chondrocytes regulated by PDMS substrate exhibited stiffness-dependent differences. Additionally, stiffness-evoked [Ca²⁺]<i>_i</i> changes were suppressed in TRPV4-KD, Piezo1-KD, or Piezo2-KD cells compared with control siRNA-treated cells, implying that any channel is fundamental for Ca²⁺ signaling induced by substrate stiffness. Furthermore, TRPV4-mediated Ca²⁺ signaling played a central role in the response of chondrocytes to 197 kPa and 78 kPa substrate, while Piezo1/2-mediated Ca²⁺ signaling played a central role in the response of chondrocytes to 54 kPa and 2 kPa substrate.</p><p><strong>Conclusions: </strong>Collectively, these findings indicate that chondrocytes might perceive and distinguish the different PCM stiffness by using different mechanosensitive ion channels.</p>","PeriodicalId":10661,"journal":{"name":"Connective Tissue Research","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39652418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}