scholarly journals High through-put identification of miR-145 targets in human articular chondrocytes

2020 ◽  
Author(s):  
Aida Martinez-Sanchez ◽  
Stefano Lazzarano ◽  
Eshita Sharma ◽  
Chris L. Murphy
Keyword(s):  
Cartilage Repair ◽  
Motif Discovery ◽  
Articular Chondrocytes ◽  
Biological Processes ◽  
Articular Chondrocyte ◽  
Coding Region ◽  
Rna Immunoprecipitation ◽  
Important Regulator ◽  
Discovery Method ◽  
Mmp13 Expression

ABSTRACTObjectiveMicroRNAs play a key role in biological processes, including cartilage development and homeostasis and are dysregulated in many diseases, including osteoarthritis. MiR-145 modulation induces profound changes in the human articular chondrocyte (HAC) phenotype, partially through direct repression of SOX9. Since miRNAs can simultaneously silence multiple targets, we aimed to identify the whole targetome of miR-145 in HACs. This information is critical if miR-145 is to be considered a target for cartilage repair.MethodsRIP-seq (RNA-immunoprecipitation plus HT-sequencing) of miRISC (miRNA-induced silencing complex) was performed in HACs overexpressing miR-145 to identify miR-145 direct targets. The motif discovery method cWords was used to assess enrichment on miR-145 seed matches in the identified targets. RT-qPCR, Western (immuno-)blot and luciferase assays were used to validate miRNA-target interactions.ResultsMiR-145 overexpression affects the expression of over 350 genes and directly targets more than 50 mRNAs through the 3’UTR or, more commonly, the coding region.We also demonstrate that miR-145 targets DUSP6, involved in cartilage organization and development, at the translational level. DUSP6 depletion using specific siRNAs lead to MMP13 up-regulation, suggesting that miR-145-mediated DUSP6 depletion contributes to the effect of miR-145 on MMP13 expression.ConclusionWe demonstrate that miR-145 directly targets several genes in primary chondrocytes including those involved in the expression of the extracellular matrix and inflammation. Thus, we propose miR-145 as an important regulator of chondrocyte function and a new target for cartilage repair.

scholarly journals High-Throughput Identification of MiR-145 Targets in Human Articular Chondrocytes

Life ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 58
Author(s):  
Aida Martinez-Sanchez ◽  
Stefano Lazzarano ◽  
Eshita Sharma ◽  
Helen Lockstone ◽  
Christopher L. Murphy
Keyword(s):  
Cartilage Repair ◽  
High Throughput ◽  
High Throughput Sequencing ◽  
Articular Chondrocytes ◽  
Articular Chondrocyte ◽  
Coding Region ◽  
Cartilage Development ◽  
Rna Immunoprecipitation ◽  
Important Regulator ◽  
Mmp13 Expression

MicroRNAs (miRNAs) play key roles in cartilage development and homeostasis and are dysregulated in osteoarthritis. MiR-145 modulation induces profound changes in the human articular chondrocyte (HAC) phenotype, partially through direct repression of SOX9. Since miRNAs can simultaneously silence multiple targets, we aimed to identify the whole targetome of miR-145 in HACs, critical if miR-145 is to be considered a target for cartilage repair. We performed RIP-seq (RNA-immunoprecipitation and high-throughput sequencing) of miRISC (miRNA-induced silencing complex) in HACs overexpressing miR-145 to identify miR-145 direct targets and used cWords to assess enrichment of miR-145 seed matches in the identified targets. Further validations were performed by RT-qPCR, Western immunoblot, and luciferase assays. MiR-145 affects the expression of over 350 genes and directly targets more than 50 mRNAs through the 3′UTR or, more commonly, the coding region. MiR-145 targets DUSP6, involved in cartilage organization and development, at the translational level. DUSP6 depletion leads to MMP13 upregulation, suggesting a contribution towards the effect of miR-145 on MMP13 expression. In conclusion, miR-145 directly targets several genes involved in the expression of the extracellular matrix and inflammation in primary chondrocytes. Thus, we propose miR-145 as an important regulator of chondrocyte function and a new target for cartilage repair.

Dynamical Analysis of bantam-Regulated Drosophila Circadian Rhythm Model

2014 ◽  
Vol 24 (12) ◽  
pp. 1450161 ◽  
Author(s):  
Ying Li ◽  
Zengrong Liu
Keyword(s):  
Circadian Rhythm ◽  
Crucial Role ◽  
Target Genes ◽  
Classical Model ◽  
Dynamical Analysis ◽  
Biological Processes ◽  
Biological Mechanisms ◽  
Environmental Perturbations ◽  
Dynamical Behaviors ◽  
Important Regulator

MicroRNAs (miRNAs) interact with 3′untranslated region (UTR) elements of target genes to regulate mRNA stability or translation, and play a crucial role in regulating many different biological processes. bantam, a conserved miRNA, is involved in several functions, such as regulating Drosophila growth and circadian rhythm. Recently, it has been discovered that bantam plays a crucial role in the core circadian pacemaker. In this paper, based on experimental observations, a detailed dynamical model of bantam-regulated circadian clock system is developed to show the post-transcriptional behaviors in the modulation of Drosophila circadian rhythm, in which the regulation of bantam is incorporated into a classical model. The dynamical behaviors of the model are consistent with the experimental observations, which shows that bantam is an important regulator of Drosophila circadian rhythm. The sensitivity analysis of parameters demonstrates that with the regulation of bantam the system is more sensitive to perturbations, indicating that bantam regulation makes it easier for the organism to modulate its period against the environmental perturbations. The effectiveness in rescuing locomotor activity rhythms of mutated flies shows that bantam is necessary for strong and sustained rhythms. In addition, the biological mechanisms of bantam regulation are analyzed, which may help us more clearly understand Drosophila circadian rhythm regulated by other miRNAs.

scholarly journals Calcium Input Potentiates the Transforming Growth Factor (TGF)-β1-dependent Signaling to Promote the Export of Inorganic Pyrophosphate by Articular Chondrocyte

2011 ◽  
Vol 286 (22) ◽  
pp. 19215-19228 ◽  
Author(s):  
Frederic Cailotto ◽  
Pascal Reboul ◽  
Sylvie Sebillaud ◽  
Patrick Netter ◽  
Jean-Yves Jouzeau ◽  
...  
Keyword(s):  
Growth Factor ◽  
Promoter Activity ◽  
Transforming Growth Factor ◽  
Articular Chondrocytes ◽  
Specific Protein ◽  
Dependent Manner ◽  
Articular Chondrocyte ◽  
Experimental Conditions ◽  
Inorganic Pyrophosphate ◽  
Tgf Β1

Transforming growth factor (TGF)-β1 stimulates extracellular PPi (ePPi) generation and promotes chondrocalcinosis, which also occurs secondary to hyperparathyroidism-induced hypercalcemia. We previously demonstrated that ANK was up-regulated by TGF-β1 activation of ERK1/2 and Ca2+-dependent protein kinase C (PKCα). Thus, we investigated mechanisms by which calcium could affect ePPi metabolism, especially its main regulating proteins ANK and PC-1 (plasma cell membrane glycoprotein-1). We stimulated articular chondrocytes with TGF-β1 under extracellular (eCa2+) or cytosolic Ca2+ (cCa2+) modulations. We studied ANK, PC-1 expression (quantitative RT-PCR, Western blotting), ePPi levels (radiometric assay), and cCa2+ input (fluorescent probe). Voltage-operated Ca2+-channels (VOC) and signaling pathways involved were investigated with selective inhibitors. Finally, Ank promoter activity was evaluated (gene reporter). TGF-β1 elevated cCa2+ and ePPi levels (by up-regulating Ank and PC-1 mRNA/proteins) in an eCa2+ dose-dependent manner. TGF-β1 effects were suppressed by cCa2+ chelation or L- and T-VOC blockade while being mostly reproduced by ionomycin. In the same experimental conditions, the activation of Ras, the phosphorylation of ERK1/2 and PKCα, and the stimulation of Ank promoter activity were affected similarly. Activation of SP1 (specific protein 1) and ELK-1 (Ets-like protein-1) transcription factors supported the regulatory role of Ca2+. SP1 or ELK-1 overexpression or blockade experiments demonstrated a major contribution of ELK-1, which acted synergistically with SP1 to activate Ank promoter in response to TGF-β1. TGF-β1 promotes input of eCa2+ through opening of L- and T-VOCs, to potentiate ERK1/2 and PKCα signaling cascades, resulting in an enhanced activation of Ank promoter and ePPi production in chondrocyte.

scholarly journals GSK5182, 4-Hydroxytamoxifen Analog, a New Potential Therapeutic Drug for Osteoarthritis

2020 ◽  
Vol 13 (12) ◽  
pp. 429
Author(s):  
Yunhui Min ◽  
Dahye Kim ◽  
Godagama Gamaarachchige Dinesh Suminda ◽  
Xiangyu Zhao ◽  
Mangeun Kim ◽  
...  
Keyword(s):  
Inflammatory Cytokines ◽  
Small Molecule ◽  
Articular Chondrocytes ◽  
Therapeutic Potential ◽  
Inverse Agonist ◽  
Therapeutic Drug ◽  
Articular Chondrocyte ◽  
Orphan Nuclear Receptors ◽  
Genetic Ablation ◽  
Pro Inflammatory Cytokines

Estrogen-related receptors (ERRs) are the first identified orphan nuclear receptors. The ERR family consists of ERRα, ERRβ, and ERRγ, regulating diverse isoform-specific functions. We have reported the importance of ERRγ in osteoarthritis (OA) pathogenesis. However, therapeutic approaches with ERRγ against OA associated with inflammatory mechanisms remain limited. Herein, we examined the therapeutic potential of a small-molecule ERRγ inverse agonist, GSK5182 (4-hydroxytamoxifen analog), in OA, to assess the relationship between ERRγ expression and pro-inflammatory cytokines in mouse articular chondrocyte cultures. ERRγ expression increased following chondrocyte exposure to various pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α. Pro-inflammatory cytokines dose-dependently increased ERRγ protein levels. In mouse articular chondrocytes, adenovirus-mediated ERRγ overexpression upregulated matrix metalloproteinase (MMP)-3 and MMP-13, which participate in cartilage destruction during OA. Adenovirus-mediated ERRγ overexpression in mouse knee joints or ERRγ transgenic mice resulted in OA. In mouse joint tissues, genetic ablation of Esrrg obscured experimental OA. These results indicate that ERRγ is involved in OA pathogenesis. In mouse articular chondrocytes, GSK5182 inhibited pro-inflammatory cytokine-induced catabolic factors. Consistent with the in vitro results, GSK5182 significantly reduced cartilage degeneration in ERRγ-overexpressing mice administered intra-articular Ad-Esrrg. Overall, the ERRγ inverse agonist GSK5182 represents a promising therapeutic small molecule for OA.

scholarly journals A highly efficient and effective motif discovery method for ChIP-seq/ChIP-chip data using positional information

2011 ◽  
Vol 40 (7) ◽  
pp. e50-e50 ◽  
Author(s):  
Xiaotu Ma ◽  
Ashwinikumar Kulkarni ◽  
Zhihua Zhang ◽  
Zhenyu Xuan ◽  
Robert Serfling ◽  
...  
Keyword(s):  
Motif Discovery ◽  
Positional Information ◽  
Chip Data ◽  
Highly Efficient ◽  
Discovery Method ◽  
Chip Chip

scholarly journals MicroRNA-92a-3p Regulates Aggrecanase-1 and Aggrecanase-2 Expression in Chondrogenesis and IL-1β-Induced Catabolism in Human Articular Chondrocytes

2017 ◽  
Vol 44 (1) ◽  
pp. 38-52 ◽  
Author(s):  
Guping Mao ◽  
Peihui Wu ◽  
Ziji Zhang ◽  
Zhiqi Zhang ◽  
Weiming Liao ◽  
...  
Keyword(s):  
Map Kinases ◽  
Articular Chondrocytes ◽  
Quantitative Polymerase Chain Reaction ◽  
Human Mesenchymal Stem Cells ◽  
Human Chondrocytes ◽  
Luciferase Reporter ◽  
Enzyme Linked Immunosorbent Assay ◽  
Repressive Effect ◽  
Important Regulator ◽  
A Disintegrin And Metalloproteinase

Background/Aims: Aggrecanase-1 (ADAMTS-4) and aggrecanase-2 (ADAMTS-5) are secreted enzymes belonging to the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family that play significant roles in the progression of osteoarthritis (OA). Here, we aimed to determine whether the expression of ADAMTS-4/5 in chondrogenesis and inflammation is regulated by microRNA-92a-3p (miR-92a-3p). Methods: MiR-92a-3p and ADAMTS-4/5 expressions were determined by quantitative polymerase chain reaction (qPCR). To investigate the repressive effect of miR-92a-3p on ADAMTS-4/5 expression, chondrogenic human mesenchymal stem cells (hMSCs) and human chondrocytes were transfected with mature miR-92a-3p or an antisense inhibitor (anti-miR-92a-3p), respectively. ADAMTS-4/5 protein production was quantified by enzyme-linked immunosorbent assay (ELISA), and miR-92a-3p involvement in IL-1β-mediated catabolic effects was examined by immunoblotting. The roles of activated MAP kinases (MAPK) and nuclear factor (NF)-κB were evaluated by using specific inhibitors. Interaction between miR-92a-3p and its putative binding site in the 3′-untranslated region (3′-UTR) of ADAMTS-4/5 mRNA was confirmed by luciferase reporter assay. Results: miR-92a-3p expression was elevated in chondrogenic hMSCs, with significantly lower expression in OA cartilage than in normal cartilage. Stimulation with IL-1β significantly reduced miR-92a-3p expression in primary human chondrocytes (PHCs). Transfection of chondrocytes with miR-92a-3p downregulated IL-1β-induced ADAMTS-4/5 expression, and the activity of a reporter construct containing the 3′-UTR of human ADAMTS-4/5 mRNA. MiR-92a-3p expression was suppressed upon IL-1β-induced activation of MAPK and NF-κB in chondrocytes. Conclusion: MiR-92a-3p is an important regulator of ADAMTS-4/5 in human chondrocytes and may contribute to the development of OA.

Facilitating In Vivo Articular Cartilage Repair by Tissue-Engineered Cartilage Grafts Produced From Auricular Chondrocytes

2017 ◽  
Vol 46 (3) ◽  
pp. 713-727 ◽  
Author(s):  
Chin-Chean Wong ◽  
Chih-Hwa Chen ◽  
Li-Hsuan Chiu ◽  
Yang-Hwei Tsuang ◽  
Meng-Yi Bai ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Articular Cartilage ◽  
Cartilage Repair ◽  
Articular Chondrocytes ◽  
Type Ii Collagen ◽  
Type Ii ◽  
Articular Cartilage Repair ◽  
3 Dimensional ◽  
Cell Conversion

Background: Insufficient cell numbers still present a challenge for articular cartilage repair. Converting heterotopic auricular chondrocytes by extracellular matrix may be the solution. Hypothesis: Specific extracellular matrix may convert the phenotype of auricular chondrocytes toward articular cartilage for repair. Study Design: Controlled laboratory study. Methods: For in vitro study, rabbit auricular chondrocytes were cultured in monolayer for several passages until reaching status of dedifferentiation. Later, they were transferred to chondrogenic type II collagen (Col II)–coated plates for further cell conversion. Articular chondrogenic profiles, such as glycosaminoglycan deposition, articular chondrogenic gene, and protein expression, were evaluated after 14-day cultivation. Furthermore, 3-dimensional constructs were fabricated using Col II hydrogel-associated auricular chondrocytes, and their histological and biomechanical properties were analyzed. For in vivo study, focal osteochondral defects were created in the rabbit knee joints, and auricular Col II constructs were implanted for repair. Results: The auricular chondrocytes converted by a 2-step protocol expressed specific profiles of chondrogenic molecules associated with articular chondrocytes. The histological and biomechanical features of converted auricular chondrocytes became similar to those of articular chondrocytes when cultivated with Col II 3-dimensional scaffolds. In an in vivo animal model of osteochondral defects, the treated group (auricular Col II) showed better cartilage repair than did the control groups (sham, auricular cells, and Col II). Histological analyses revealed that cartilage repair was achieved in the treated groups with abundant type II collagen and glycosaminoglycans syntheses rather than elastin expression. Conclusion: The study confirmed the feasibility of applying heterotopic chondrocytes for cartilage repair via extracellular matrix–induced cell conversion. Clinical Relevance: This study proposes a feasible methodology to convert heterotopic auricular chondrocytes for articular cartilage repair, which may serve as potential alternative sources for cartilage repair.

scholarly journals Human Serum for Culture of Articular Chondrocytes

2005 ◽  
Vol 14 (7) ◽  
pp. 469-479 ◽  
Author(s):  
Tommi Tallheden ◽  
Josefine Van Der Lee ◽  
Camilla Brantsing ◽  
Jan-Eric Månsson ◽  
Eva Sjögren-Jansson ◽  
...  
Keyword(s):  
Growth Factor ◽  
Human Serum ◽  
Articular Chondrocytes ◽  
Autologous Serum ◽  
Foreign Protein ◽  
Articular Chondrocyte ◽  
Cell Therapies ◽  
High Proliferation Rate ◽  
Protein Contamination

In the field of cell and tissue engineering, culture expansion of human cells in monolayer plays an important part. Traditionally, cell cultures have been supplemented with serum to support attachment and proliferation, but serum is a potential source of foreign protein contamination and viral protein transmission. In this study, we evaluated the use of human serum for experimental human articular chondrocyte expansion and to develop a method for preparation of large volumes of high-quality human serum from healthy blood donors. Human autologous serum contained high levels of epidermal-derived growth factor and platelet-derived growth factor-AB and supported proliferation up to 7 times higher than FCS in primary chondrocyte cultures. By letting the coagulation take place in a commercially available transfusion bag overnight, up to 250 ml of growth factor-rich human serum could be obtained from one donor. The allogenic human serum supported high proliferation rate without loosing expression of cartilage-specific genes. The expanded chondrocytes were able to redifferentiate and form cartilage matrix in comparable amounts to autologous serums. In conclusion, the transfusion bags allow preparation of large volumes of growth factor-rich human serum with the capacity to support in vitro cell expansion. The data further indicate that by controlling the coagulation process there are possibilities of optimizing the release of growth factors for other emerging cell therapies.

scholarly journals Articular chondrocyte-derived exosomes promote cartilage differentiation of human umbilical cord mesenchymal stem cells by activation of autophagy

2020 ◽  
Author(s):  
Ke Ma ◽  
Bo Zhu ◽  
Zetao Wang ◽  
Peian Cai ◽  
Mingwei He ◽  
...  
Keyword(s):  
Stem Cells ◽  
Umbilical Cord ◽  
Cartilage Repair ◽  
Chondrogenic Differentiation ◽  
Phenotypic Expression ◽  
Cartilage Regeneration ◽  
Human Umbilical Cord ◽  
Articular Chondrocyte ◽  
Differentiation And Proliferation

Abstract Background Umbilical cord mesenchymal stem cell (HUCMSC)-based therapies were previously utilised for cartilage regeneration because of the chondrogenic potential of MSCs. However, chondrogenic differentiation of HUMSCs is limited by the administration of growth factors like TGF-β that may cause cartilage hypertrophy. It has been reported that exosomes could modulate the phenotypic expression of stem cells. However, the role of human chondrogenic-derived exosomes (C-EXOs) in chondrogenic differentiation of HUCMSCs has not been reported. Results In this study, we successfully isolated chondrocyte-derived exosomes (C-EXO) from human multi-finger cartilage and found that C-EXO efficiently promoted the proliferation and chondrogenic differentiation of HUCMSCs, evidenced by highly expressed aggrecan (ACAN), COL2A and SOX-9. Also, the expression of the fibrotic marker, COL1A and hypertrophic marker, COL10, was significantly lower than that induced by TGF-β. In vivo, stimulation of C-EXO accelerated HUCMSCs-mediated cartilage repair in rabbit models. Furthermore, C-EXO led to increasing autophagosomes during the process of chondrogenic differentiation, indicating that C-EXO promoted cartilage regeneration might be through the activation of autophagy. Conclusions C-EXOs play an essential role in fostering chondrogenic differentiation and proliferation of HUCMSCs, which may be beneficial for articular cartilage repair.

Sign in / Sign up

Export Citation Format

Share Document