scholarly journals Integrin β1 Gene Therapy Enhances in Vitro Creation of Tissue-Engineered Cartilage Under Periodic Mechanical Stress

2015 ◽  
Vol 37 (4) ◽  
pp. 1301-1314 ◽  
Author(s):  
Wenwei Liang ◽  
Chunhui Zhu ◽  
Feng Liu ◽  
Weiding Cui ◽  
Qing Wang ◽  
...  
Keyword(s):  
Mechanical Stress ◽  
Type Ii Collagen ◽  
Cell Types ◽  
Signal Pathways ◽  
Matrix Synthesis ◽  
Integrin Β1 ◽  
Chondrocyte Proliferation ◽  
Engineered Cartilage

Background/Aims: Periodic mechanical stress activates integrin β1-initiated signal pathways to promote chondrocyte proliferation and matrix synthesis. Integrin β1 overexpression has been demonstrated to play important roles in improving the activities and functions of several non-chondrocytic cell types. Therefore, in the current study, we evaluated the effects of integrin β1 up-regulation on periodic mechanical stress-induced chondrocyte proliferation, matrix synthesis and ERK1/2 phosphorylation in chondrocyte monolayer culture, and evaluated the quality of tissue-engineered cartilage constructed in vitro under periodic mechanical stress combined with integrin β1 up-regulation. Methods and Results: Our results revealed that under periodic mechanical stress, pre-treatment with integrin β1-wild type vector significantly enhanced chondrocyte proliferation and matrix synthesis and promoted ERK1/2 phosphorylation in comparison to mock transfectants. Furthermore, when chondrocytes were seeded in PLGA scaffolds, more accumulated GAG and type II collagen tissue were detected after Lv-integrin β1 transfection compared with sham controls exposed to periodic mechanical stress. In contrast, in the Lv-shRNA-integrin β1 group, the opposite results were observed. Conclusion: Our findings collectively suggest that in addition to periodic mechanical stress, integrin β1 up-regulation in chondrocytes could further improve the quality of tissue-engineered cartilage.

scholarly journals Periodic Mechanical Stress INDUCES Chondrocyte Proliferation and Matrix Synthesis via CaMKII-Mediated Pyk2 Signaling

2017 ◽  
Vol 42 (1) ◽  
pp. 383-396 ◽  
Author(s):  
Wenwei Liang ◽  
Zeng Li ◽  
Zhen Wang ◽  
Jinchun Zhou ◽  
Huanghe Song ◽  
...  
Keyword(s):  
Mechanical Stress ◽  
Cell Counting ◽  
Synthesis Methods ◽  
Matrix Synthesis ◽  
Gene Expressions ◽  
Chondrocyte Proliferation ◽  
Direct Cell ◽  
Engineered Cartilage ◽  
Signal Activation

Background/Aims: Periodic mechanical stress can promote chondrocyte proliferation and matrix synthesis to improve the quality of tissue-engineered cartilage. Although the integrin β1–ERK1/2 signal cascade has been implicated in periodic mechanical stress-induced mitogenic effects in chondrocytes, the precise mechanisms have not been fully established. The current study was designed to probe the roles of CaMKII and Pyk2 signaling in periodic mechanical stress-mediated chondrocyte proliferation and matrix synthesis. Methods: Chondrocytes were subjected to periodic mechanical stress, proliferation was assessed by direct cell counting and CCK-8 assay; gene expressions were analyzed using quantitative real-time PCR, protein abundance by Western blotting. Results: Mechanical stress, markedly enhanced the phosphorylation levels of Pyk2 at Tyr402 and CaMKII at Thr286. Both suppression of Pyk2 with Pyk2 inhibitor PF431396 or Pyk2 shRNA and suppression of CaMKII with CaMKII inhibitor KN-93 or CaMKII shRNA blocked periodic mechanical stress-induced chondrocyte proliferation and matrix synthesis. Additionally, either pretreatment with KN-93 or shRNA targeted to CaMKII prevented the activation of ERK1/2 and Pyk2 under conditions of periodic mechanical stress. Interestingly, in relation to periodic mechanical stress, in the context of Pyk2 inhibition with PF431396 or its targeted shRNA, only the phosphorylation levels of ERK1/2 were abrogated, while CaMKII signal activation was not affected. Moreover, the phosphorylation levels of CaMKII- Thr286 and Pyk2- Tyr402 were abolished after pretreatment with blocking antibody against integrinβ1 exposed to periodic mechanical stress. Conclusion: Our results collectively indicate that periodic mechanical stress promotes chondrocyte proliferation and matrix synthesis through the integrinβ1–CaMKII–Pyk2–ERK1/2 signaling cascade.

BMP2 Is Required for Postnatal Maintenance of Osteochondral Tissues of the Temporomandibular Joint

Cartilage ◽  
2020 ◽  
pp. 194760352098015
Author(s):  
Mara H. O’Brien ◽  
Eliane H. Dutra ◽  
Shivam Mehta ◽  
Po-Jung Chen ◽  
Sumit Yadav
Keyword(s):  
Age Groups ◽  
Mandibular Condyle ◽  
Bone Morphogenetic Protein 2 ◽  
Matrix Synthesis ◽  
Cartilage Growth ◽  
Chondrocyte Proliferation ◽  
Conditional Deletion ◽  
Morphogenetic Protein

Objective Bone morphogenetic protein 2 (BMP2) plays important roles in cartilage growth and development. Paradoxically, elevated levels of BMP2 leads to hypertrophic differentiation and osteoarthritis of cartilage. We examined the in vivo loss of BMP2 in cells expressing aggrecan of the mandibular condyle and knee. Design Three-week-old BMP2 flox/flox- CreER-positive mice and their Cre-negative littermates were treated with tamoxifen and raised until 3 or 6 months. We also investigated the direct effects of BMP2 on chondrocytes in vitro. Cells from the mandibular condyle of mice were treated with recombinant human BMP2 (rhBMP2) or rhNoggin (inhibitor of BMP2 signaling). Results Conditional deletion of BMP2 caused breakage of the cartilage integrity in the mandibular condyle of mice from both age groups, accompanied by a decrease in cartilage thickness, matrix synthesis, mineralization, chondrocyte proliferation, and increased expression of degeneration markers, while the effects at articular cartilage were not significant. In vitro results revealed that rhBMP2 increased chondrocyte proliferation, mineralization, and differentiation, while noggin induced opposite effects. Conclusions In conclusion, BMP2 is essential for postnatal maintenance of the osteochondral tissues of the mandibular condyle.

In vitro p53 and/or Rb antisense oligonucleotide treatment in association with growth factors induces the proliferation of peripheral hematopoietic progenitors

1995 ◽  
Vol 108 (3) ◽  
pp. 1287-1293
Author(s):  
T. Mahdi ◽  
A. Brizard ◽  
C. Millet ◽  
P. Dore ◽  
J. Tanzer ◽  
...  
Keyword(s):  
Tumor Suppressor ◽  
Cell Types ◽  
Suppressor Gene ◽  
Antisense Oligodeoxynucleotide ◽  
Signal Pathways ◽  
Semisolid Medium ◽  
Gm Csf ◽  
Colony Forming Units ◽  
Macrophage Colony

In this work we intended to determine whether p53 and/or retinoblastoma (Rb) tumor suppressor genes are involved at specific stages in the process of in vitro human peripheral stem cell hematopoiesis. Mononuclear peripheral blood cells were depleted of adherent cells and T lymphocytes (A-T-PMCs). Cells were then cultured in semisolid medium, under conditions that favor the growth of specific progenitor cell types. A-T-PMCs were exposed to p53 and/or Rb sense, scrambled DNA and antisense oligodeoxynucleotides. p53 and/or Rb antisenses (but not their senses or scrambled DNA) treatment of A-T-PMCs resulted in a significantly increase in the number of granulocyte/macrophage colony-forming units (CFU-GM) in the presence of interleukin-3 (IL-3) and/or granulocyte/macrophage colony-stimulating factor (GM-CSF). After antisense treatment, blast forming units/erythroblasts (BFU-E) derived from A-T-PMCs cultured in the presence of IL-3 + erythropoietin (Epo) were also increased whereas colony forming units/erythroblasts (CFU-E) were not markedly affected in the presence of Epo only. Megakaryocytic colony (CFU-Meg) formation from A-T-PMCs in the presence of interleukin-6 (IL-6) + IL-3 + Epo was also increased after antisense oligodeoxynucleotide treatment. These results are consistent with the hypothesis that p53 and Rb tumor suppressor gene products are involved in the control of distinct signal pathways in different peripheral progenitor cells.

scholarly journals In Vitro Weight-Loaded Cell Models for Understanding Mechanodependent Molecular Pathways Involved in Orthodontic Tooth Movement: A Systematic Review

2018 ◽  
Vol 2018 ◽  
pp. 1-17 ◽  
Author(s):  
Mila Janjic ◽  
Denitsa Docheva ◽  
Olivera Trickovic Janjic ◽  
Andrea Wichelhaus ◽  
Uwe Baumert
Keyword(s):  
Systematic Review ◽  
Mechanical Stress ◽  
Tooth Movement ◽  
Orthodontic Tooth Movement ◽  
Compressive Force ◽  
Cell Types ◽  
Dental Stem Cells ◽  
Protein Protein Interaction ◽  
Different Cell Types

Cells from the mesenchymal lineage in the dental area, including but not limited to PDL fibroblasts, osteoblasts, and dental stem cells, are exposed to mechanical stress in physiological (e.g., chewing) and nonphysiological/therapeutic (e.g., orthodontic tooth movement) situations. Close and complex interaction of these different cell types results in the physiological and nonphysiological adaptation of these tissues to mechanical stress. Currently, different in vitro loading models are used to investigate the effect of different types of mechanical loading on the stress adaptation of these cell types. We performed a systematic review according to the PRISMA guidelines to identify all studies in the field of dentistry with focus on mechanobiology using in vitro loading models applying uniaxial static compressive force. Only studies reporting on cells from the mesenchymal lineage were considered for inclusion. The results are summarized regarding gene expression in relation to force duration and magnitude, and the most significant signaling pathways they take part in are identified using protein-protein interaction networks.

scholarly journals In Vitro Generation of Cartilage-Carrier-Constructs on Hydroxylapatite Ceramics with Different Surface Structures

2008 ◽  
Vol 2 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Katharina Wiegandt ◽  
Christiane Goepfert ◽  
Teresa Richter ◽  
Daniel Fritsch ◽  
Rolf Janßen ◽  
...  
Keyword(s):  
Surface Structure ◽  
Biochemical Properties ◽  
Surface Structures ◽  
Cartilage Defects ◽  
Commercial Grade ◽  
First Results ◽  
Hydroxylapatite Ceramics ◽  
Engineered Cartilage

Tissue engineering approaches for healing cartilage defects are partly limited by the inability to fix cartilage to bone during implantation. To overcome this problem, cartilage can be - already in vitro - generated on a ceramic carrier which serves as bone substitute. In this study, the influence of a hydroxylapatite carrier and its surface structure on the quality of tissue engineered cartilage was investigated. Application of the carrier reduced significantly biomechanical and biochemical properties of the generated tissue. In addition, slight changes in the quality of the formed matrix, in the adhesive strength between cartilage and biomaterial and in attachment and proliferation of a chondrocyte monolayer could be observed for commercial grade carriers, with respect to modified topographies obtained by smooth grinding/polishing. These first results demonstrated an influence of the carrier and its surface structure, but further research is needed for explaining the described effects and for optimization of cartilage-carrier-constructs.

scholarly journals The Stability of the Induced Epigenetic Programs

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Maria J. Barrero
Keyword(s):  
Stem Cells ◽  
Somatic Cells ◽  
Cell Types ◽  
Specific Cell ◽  
Cell Type ◽  
Pluripotent Cells ◽  
Potential Applications ◽  
The Stability

For many years scientists have been attracted to the possibility of changing cell identity. In the last decades seminal discoveries have shown that it is possible to reprogram somatic cells into pluripotent cells and even to transdifferentiate one cell type into another. In view of the potential applications that generating specific cell types in the laboratory can offer for cell-based therapies, the next important questions relate to the quality of the induced cell types. Importantly, epigenetic aberrations in reprogrammed cells have been correlated with defects in differentiation. Therefore, a look at the epigenome and understanding how different regulators can shape it appear fundamental to anticipate potential therapeutic pitfalls. This paper covers these epigenetic aspects in stem cells, differentiation, and reprogramming and discusses their importance for the safety of in vitro engineered cell types.

scholarly journals The Effect of Varying Concentrations and Application Periods of Chondroitinase ABC on Tissue-Engineered Cartilage

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Eric Tong ◽  
Grace D. O'Connell ◽  
Terri-Ann N. Kelly ◽  
Clark T. Hung
Keyword(s):  
Mechanical Properties ◽  
Articular Cartilage ◽  
Treatment Option ◽  
Type Ii Collagen ◽  
Treated Group ◽  
Cartilage Tissue ◽  
Type Ii ◽  
Chondroitinase Abc ◽  
Engineered Cartilage

Osteoarthritis, a chronic malady characterized by joint pain and swelling, is caused by damage to articular cartilage and is perpetuated by low-grade inflammation.  Treatments for osteoarthritis do exist, but many treatments focus on coping with the disease rather than curing it.  Surgical options that replace damaged cartilage tissue with that of donor cartilage tissue or cartilage tissue from other parts of articular joints face complications especially when the tissue is not of the correct size or does not have native-like properties. A more suitable treatment option for osteoarthritis is to develop an in vitro tissue-engineered cartilage construct that can be grown using the patient’s own cells and to surgically remove the patient’s damaged cartilage and replace it with the tissue-engineered cartilage. A challenge in developing such a treatment option is producing tissue-engineered cartilage with mechanical properties akin to those of native human articular cartilage. This challenge may be overcome by maximizing the production of type II collagen by the chondrocytes in vitro. One way to maximize collagen production is through the application of chondroitinase ABC, an enzyme which temporarily suppresses proteoglycans in the cartilage matrix to create more space for type II collagen to develop. In this study, two two levels of cABC treatment were applied (“high” and “low”) to cartilage tissue constructs. The “low” cABC treated group received daily feeding of 0.075 U/mL from day 14 to 21 followed by a replacement of chondrogenic media without cABC.  The “high” cABC treated group received a single addition of 0.15 U/mL from day 14 to 16 followed by a replacement of chondrogenic media without cABC.  At the end of 42 days, the constructs were subjected to mechanical testing and biochemical analyses. These analyses showed that the high cABC treatment yielded more native-like mechanical properties when compared to the low cABC treatment and the control results.  Biochemical and histological analyses confirmed that the proteoglycan and collagen II content were higher in the low and high cABC treated groups when compared to the control. All analyses show that the most efficient application of chondroitinase ABC is through a two day duration treatment of a higher concentration (0.15 U/mL).

Interleukin-4 protects matrix synthesis in chondrocytes under excessive mechanical stress in vitro

2004 ◽  
Vol 14 (4) ◽  
pp. 296-300 ◽  
Author(s):  
Akira Shimizu ◽  
Shohei Watanabe ◽  
Seiji Iimoto ◽  
Haruyasu Yamamoto
Keyword(s):  
Mechanical Stress ◽  
Interleukin 4 ◽  
Matrix Synthesis

scholarly journals Method for in vitro production of cartilage microtissues from scaffold-free spheroids composed of human adipose-derived stem cells

2020 ◽  
Vol 7 (4) ◽  
pp. 3697-3708
Author(s):  
Vy Thi-Kieu Tu ◽  
Ha Thi-Ngan Le ◽  
Xuan Hoang-Viet To ◽  
Phuc Dang-Ngoc Nguyen ◽  
Phat Duc Huynh ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cartilage Damage ◽  
Cartilage Regeneration ◽  
Type Ii Collagen ◽  
Adipose Derived Stem Cells ◽  
Type Ii ◽  
In Vitro Production ◽  
Engineered Cartilage

Introduction: Cartilage damage is one of the injuries that is difficult for the human body to self-repair due to the avascular and completely mature tissue with only few stem or progenitor cells present. Recently, some studies showed that engineered cartilage tissues could be used to treat or improve this injury. This study aimed to produce the cartilage microtissues from the differentiation of scaffold-free spheroids composed of human adipose-derived stem cells. Methods: Human adipose-derived stem cells (ADSCs) were isolated and expanded following the previously published study. They were then cultured in the non-adherent condition to produce spheroids. The spheroids of the ADSCs were collected and induced into cartilage microtissues in the inducible medium for 21 days. The cartilage microtissue was characterized by some cartilage phenotype markers, including the accumulation of extracellular matrix proteins (aggrecan, glycosaminoglycan, and type II collagen), and the expression of certain genes specific to chondrocytes (Sox9, Col2, Col1, and Acan). Results: The results showed that the expression of chondrocyte-specific genes gradually increased during the 21 days of culture for differentiation. On day 21, the microtissues expressed aggrecan, glycosaminoglycan, and type II collagen proteins. Conclusion: This study demonstrated that cartilage microtissues could easily be produced from scaffold-free spheroids from ADSCs. Thus, cartilage microtissues can be produced in this manner for in vivo transplantation to promote cartilage regeneration, or to produce cartilage tissues for in vitro studies.  

scholarly journals Electromagnetic Field as a Treatment for Cerebral Ischemic Stroke

2021 ◽  
Vol 8 ◽  
Author(s):  
Amanda Moya Gómez ◽  
Lena Pérez Font ◽  
Bert Brône ◽  
Annelies Bronckaers
Keyword(s):  
Ischemic Stroke ◽  
Treatment Options ◽  
Cell Types ◽  
Cerebral Stroke ◽  
Signal Pathways ◽  
Extensive Literature ◽  
New Therapeutic Approaches ◽  
Cerebral Ischemic Stroke ◽  
Cerebral Ischemic

Cerebral stroke is a leading cause of death and adult-acquired disability worldwide. To this date, treatment options are limited; hence, the search for new therapeutic approaches continues. Electromagnetic fields (EMFs) affect a wide variety of biological processes and accumulating evidence shows their potential as a treatment for ischemic stroke. Based on their characteristics, they can be divided into stationary, pulsed, and sinusoidal EMF. The aim of this review is to provide an extensive literature overview ranging from in vitro to even clinical studies within the field of ischemic stroke of all EMF types. A thorough comparison between EMF types and their effects is provided, as well as an overview of the signal pathways activated in cell types relevant for ischemic stroke such as neurons, microglia, astrocytes, and endothelial cells. We also discuss which steps have to be taken to improve their therapeutic efficacy in the frame of the clinical translation of this promising therapy.

Sign in / Sign up

Export Citation Format

Share Document