scholarly journals Distinct Concentration-Dependent Molecular Pathways Regulate Bone Cell Responses to Cobalt and Chromium Exposure from Joint Replacement Prostheses

2021 ◽  
Vol 22 (10) ◽  
pp. 5225
Author(s):  
Karan Shah ◽  
Mark Dunning ◽  
Alison Gartland ◽  
J Wilkinson
Keyword(s):  
Gene Expression ◽  
Joint Replacement ◽  
Bone Cells ◽  
Osteoclast Differentiation ◽  
Gene Clusters ◽  
Bone Cell ◽  
Metal Exposure ◽  
Metal Debris ◽  
Gene Expression Response

Systemic cobalt (Co) and chromium (Cr) concentrations may be elevated in patients with metal joint replacement prostheses. Several studies have highlighted the detrimental effects of this exposure on bone cells in vitro, but the underlying mechanisms remain unclear. In this study, we use whole-genome microarrays to comprehensively assess gene expression in primary human osteoblasts, osteoclast precursors and mature resorbing osteoclasts following exposure to clinically relevant circulating versus local periprosthetic tissue concentrations of Co2+ and Cr3+ ions and CoCr nanoparticles. We also describe the gene expression response in osteoblasts on routinely used prosthesis surfaces in the presence of metal exposure. Our results suggest that systemic levels of metal exposure have no effect on osteoblasts, and primarily inhibit osteoclast differentiation and function via altering the focal adhesion and extracellular matrix interaction pathways. In contrast, periprosthetic levels of metal exposure inhibit both osteoblast and osteoclast activity by altering HIF-1α signaling and endocytic/cytoskeletal genes respectively, as well as increasing inflammatory signaling with mechanistic implications for adverse reactions to metal debris. Furthermore, we identify gene clusters and KEGG pathways for which the expression correlates with increasing Co2+:Cr3+ concentrations, and has the potential to serve as early markers of metal toxicity. Finally, our study provides a molecular basis for the improved clinical outcomes for hydroxyapatite-coated prostheses that elicit a pro-survival osteogenic gene signature compared to grit-blasted and plasma-sprayed titanium-coated surfaces in the presence of metal exposure.

Novel in vitro microfluidic platform for osteocyte mechanotransduction studies

2020 ◽  
Vol 12 (12) ◽  
pp. 303-310
Author(s):  
Liangcheng Xu ◽  
Xin Song ◽  
Gwennyth Carroll ◽  
Lidan You
Keyword(s):  
Shear Stress ◽  
Drug Targets ◽  
Fluid Shear Stress ◽  
Bone Cells ◽  
Osteoclast Differentiation ◽  
Bone Cell ◽  
Interstitial Fluid Flow ◽  
Molecule Transport ◽  
Flow Shear Stress

Abstract Osteocytes are the major mechanosensing cells in bone remodeling. Current in vitro bone mechanotransduction research use macroscale devices such as flow chambers; however, in vitro microfluidic devices provide an optimal tool to better understand this biological process with its flexible design, physiologically relevant dimensions and high-throughput capabilities. This project aims to design and fabricate a multi-shear stress, co-culture platform to study the interaction between osteocytes and other bone cells under varying flow conditions. Standard microfluidic design utilizing changing geometric parameters is used to induce different flow rates that are directly proportional to the levels of shear stress, with devices fabricated from standard polydimethylsiloxane (PDMS)-based softlithography processes. Each osteocyte channel (OCY) is connected to an adjacent osteoclast channel (OC) by 20-μm perfusion channels for cellular signaling molecule transport. Significant differences in RANKL levels are observed between channels with different shear stress levels, and we observed that pre-osteoclast differentiation was directly affected by adjacent flow-stimulated osteocytes. Significant decrease in the number of differentiating osteoclasts is observed in the OC channel adjacent to the 2-Pa shear stress OCY channel, while differentiation adjacent to the 0.5-Pa shear stress OCY channel is unaffected compared with no-flow controls. Addition of zoledronic acid showed a significant decrease in osteoclast differentiation, compounding to effect instigated by increasing fluid shear stress. Using this platform, we are able to mimic the interaction between osteocytes and osteoclasts in vitro under physiologically relevant bone interstitial fluid flow shear stress. Our novel microfluidic co-culture platform provides an optimal tool for bone cell mechanistic studies and provides a platform for the discovery of potential drug targets for clinical treatments of bone-related diseases.

Early response of gene clusters is associated with mouse lung resistance or sensitivity to cigarette smoke

2009 ◽  
Vol 296 (3) ◽  
pp. L418-L429 ◽  
Author(s):  
Eleonora Cavarra ◽  
Paolo Fardin ◽  
Silvia Fineschi ◽  
Annamaria Ricciardi ◽  
Giovanna De Cunto ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cigarette Smoke ◽  
Gene Clusters ◽  
Early Response ◽  
Cigarette Smoke Exposure ◽  
Mouse Lung ◽  
Individual Response ◽  
Molecular Signaling ◽  
Gene Expression Response ◽  
Real Time Quantitative Pcr

We have investigated the effects of cigarette smoke exposure in three different strains of mice. DBA/2 and C57BL/6J are susceptible to smoke and develop different lung changes in response to chronic exposure, whereas ICR mice are resistant to smoke and do not develop emphysema. The present study was carried out to determine early changes in the gene expression profile of mice exposed to cigarette smoke with either a susceptible or resistant phenotype. The three strains of mice were exposed to smoke from three cigarettes per day, 5 days/wk, for 4 wk. Microarray analysis was carried out on total RNA extracted from the lung using the Affymetrix platform. Cigarette smoke modulates several clusters of genes (i.e., proemphysematous, acute phase response, and cell adhesion) in smoke-sensitive DBA/2 or C57BL/6J strains, but the same genes are not altered by smoke in ICR resistant mice. Only a few genes were commonly modulated by smoke in the three strains of mice. This pattern of gene expression suggests that the response to smoke is strain-dependent and may involve different molecular signaling pathways. Real-time quantitative PCR was used to verify the pattern of modulation of selected genes and their potential biological relevance. We conclude that gene expression response to smoke is highly dependent on the mouse genetic background. We speculate that the definition of gene clusters associated, to various degrees, with mouse susceptibility or resistance to smoke may be instrumental in defining the molecular basis of the individual response to smoke-induced lung injury in humans.

scholarly journals Minireview: Transcriptional Regulation in Development of Bone

Endocrinology ◽  
2005 ◽  
Vol 146 (3) ◽  
pp. 1012-1017 ◽  
Author(s):  
Tatsuya Kobayashi ◽  
Henry Kronenberg
Keyword(s):  
Gene Expression ◽  
Transcriptional Regulation ◽  
Transcription Factors ◽  
Bone Cells ◽  
Genetic Manipulation ◽  
Bone Development ◽  
Regulation Of Gene Expression ◽  
Bone Cell ◽  
Cellular Functions ◽  
Multiple Differentiation

Regulation of gene expression by transcription factors is one of the major mechanisms for controlling cellular functions. Recent advances in genetic manipulation of model animals has allowed the study of the roles of various genes and their products in physiological settings and has demonstrated the importance of specific transcription factors in bone development. Three lineages of bone cells, chondrocytes, osteoblasts, and osteoclasts, develop and differentiate according to their distinct developmental programs. These cells go through multiple differentiation stages, which are often regulated by specific transcription factors. In this minireview, we will discuss selected transcription factors that have been demonstrated to critically affect bone cell development. Further study of these molecules will lead to deeper understanding in mechanisms that govern development of bone.

scholarly journals Protocol of Co-Culture of Human Osteoblasts and Osteoclasts to Test Biomaterials for Bone Tissue Engineering

2022 ◽  
Vol 5 (1) ◽  
pp. 8
Author(s):  
Giorgia Borciani ◽  
Giorgia Montalbano ◽  
Nicola Baldini ◽  
Chiara Vitale-Brovarone ◽  
Gabriela Ciapetti
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Bone Cells ◽  
Bone Cell ◽  
Seeding Density ◽  
Bone Homeostasis ◽  
Bone Microenvironment

New biomaterials and scaffolds for bone tissue engineering (BTE) applications require to be tested in a bone microenvironment reliable model. On this assumption, the in vitro laboratory protocols with bone cells represent worthy experimental systems improving our knowledge about bone homeostasis, reducing the costs of experimentation. To this day, several models of the bone microenvironment are reported in the literature, but few delineate a protocol for testing new biomaterials using bone cells. Herein we propose a clear protocol to set up an indirect co-culture system of human-derived osteoblasts and osteoclast precursors, providing well-defined criteria such as the cell seeding density, cell:cell ratio, the culture medium, and the proofs of differentiation. The material to be tested may be easily introduced in the system and the cell response analyzed. The physical separation of osteoblasts and osteoclasts allows distinguishing the effects of the material onto the two cell types and to evaluate the correlation between material and cell behavior, cell morphology, and adhesion. The whole protocol requires about 4 to 6 weeks with an intermediate level of expertise. The system is an in vitro model of the bone remodeling system useful in testing innovative materials for bone regeneration, and potentially exploitable in different application fields. The use of human primary cells represents a close replica of the bone cell cooperation in vivo and may be employed as a feasible system to test materials and scaffolds for bone substitution and regeneration.

Control of Oriented Extracellular Matrix Similar to Anisotropic Bone Microstructure

2014 ◽  
Vol 783-786 ◽  
pp. 72-77 ◽  
Author(s):  
Takayoshi Nakano ◽  
Aira Matsugaki ◽  
Takuya Ishimoto ◽  
Mitsuharu Todai ◽  
Ai Serizawa ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Bone Tissue ◽  
Bone Cells ◽  
Crystal Surface ◽  
Early Stage ◽  
Bone Microstructure ◽  
Bone Cell ◽  
Collagen Fibers

Bone microstructure is dominantly composed of anisotropic extracellular matrix (ECM) in which collagen fibers and epitaxially-oriented biological apatite (BAp) crystals are preferentially aligned depending on the bone anatomical position, resulting in exerting appropriate mechanical function. The regenerative bone in bony defects is however produced without the preferential alignment of collagen fibers and the c-axis of BAp crystals, and subsequently reproduced to recover toward intact alignment. Thus, it is necessary to produce the anisotropic bone-mimetic tissue for the quick recovery of original bone tissue and the related mechanical ability in the early stage of bone regeneration. Our group is focusing on the methodology for regulating the arrangement of bone cells, the following secretion of collagen and the self-assembled mineralization by oriented BAp crystallites. Cyclic stretching in vitro to bone cells, principal-stress loading in vivo on scaffolds, step formation by slip traces on Ti single crystal, surface modification by laser induced periodic surface structure (LIPSS), anisotropic collagen substrate with the different degree of orientation, etc. can dominate bone cell arrangement and lead to the construction of the oriented ECM similar to the bone tissue architecture. This suggests that stress/strain loading, surface topography and chemical anisotropy are useful to produce bone-like microstructure in order to promote the regeneration of anisotropic bone tissue and to understand the controlling parameters for anisotropic osteogenesis induction.

Gene expression response of the rat small intestine following oralSalmonellainfection

2007 ◽  
Vol 30 (2) ◽  
pp. 123-133 ◽  
Author(s):  
Wendy Rodenburg ◽  
Ingeborg M. J. Bovee-Oudenhoven ◽  
Evelien Kramer ◽  
Roelof van der Meer ◽  
Jaap Keijer
Keyword(s):  
Gene Expression ◽  
Expression Profiles ◽  
Inflammatory Marker ◽  
Molecular Response ◽  
Lipocalin 2 ◽  
Ileal Mucosa ◽  
Gene Expression Response ◽  
Expression Response

Data on the molecular response of the intestine to the food-borne pathogen Salmonella are derived from in vitro studies, whereas in vivo data are lacking. We performed an oral S. enteritidis infection study in Wistar rats to obtain insight in the in vivo response in time. Expression profiles of ileal mucosa (IM) and Peyer's patches (PP) were generated using DNA microarrays at days 1, 3, and 6 postinfection. An overview of Salmonella-regulated processes was obtained and confirmed by quantitative real-time PCR on pooled and individual samples. Salmonella-induced gene expression responses in vivo are fewer and smaller than observed in vitro, and the response develops over a longer period of time. Few effects are seen at day 1 and mainly occur in IM, suggesting the mucosa as the primary site of invasion. Later, a bigger response is observed, especially in PP. Decreased expression of anti-microbial peptides genes (in IM at day 1) suggests inhibition of this process by Salmonella. Newly identified target processes are carbohydrate transport (increased expression in IM at day 1) and phase I and phase II detoxification (decreased expression at days 3 and 6). Increase of cytokine and chemokine expression occurs at later time points, both in PP and IM. Pancreatitis-associated protein, lipocalin 2, and calprotectin, potential inflammatory marker proteins, showed induced expression from day 3 onward. We conclude that the in vivo gene expression response of the ileum to Salmonella differs to a large extent from the response seen in vitro.

Study on Bone Cell Adaptability of α-TCP/HAp Functionally Graded Porous Beads for Biomaterials Application

2010 ◽  
Vol 76 ◽  
pp. 143-146
Author(s):  
S. Ohtake ◽  
T. Asaoka ◽  
K. Furukawa ◽  
T. Ushida ◽  
T. Tateishi
Keyword(s):  
Bone Cells ◽  
High Strength ◽  
Bone Cell ◽  
Functionally Graded ◽  
The Body ◽  
Tissue Adhesive ◽  
Adhesive Properties ◽  
Living Body ◽  
Porous Beads

Porous beads of bioactive ceramics such as HAp, TCP are considered to be promising as excellent scaffolds for cultivating bone cells. To realize this type of beads which maintains the function of scaffold with sufficient strength up to growth of new bone, and is expected to absorbed completely after the growth, a-TCP/ HAp functionally graded porous beads were fabricated. HAp is bioactive material which has both high strength and better tissue-adhesive properties, but that is not readily absorbed by the human body. On the contrary, a-TCP is highly bioabsorbable; it is quickly absorbed by the body, and, therefore, disappears before bone is completely replaced. Fabricated new beads are composed of a-TCP at the center and HAp at the surface, to control the solubility in living body. Bone cell adaptability of these beads were confirmed in vitro.

scholarly journals Evolutionary insights into primate skeletal gene regulation using a comparative cell culture model

2021 ◽  
Author(s):  
Genevieve Housman ◽  
Emilie Briscoe ◽  
Yoav Gilad
Keyword(s):  
Gene Expression ◽  
Gene Regulation ◽  
Bone Cells ◽  
Cell Types ◽  
Differentially Expressed ◽  
Functional Genomic ◽  
Cell Culture Model ◽  
Culture Model ◽  
Study Gene Regulation

AbstractThe evolution of complex skeletal traits in primates was likely influenced by both genetic and environmental factors. Because skeletal tissues are notoriously challenging to study using functional genomic approaches, they remain poorly characterized even in humans, let alone across multiple species. The challenges involved in obtaining functional genomic data from the skeleton, combined with the difficulty of obtaining such tissues from nonhuman apes, motivated us to consider an alternative in vitro system with which to comparatively study gene regulation in skeletal cell types. Specifically, we differentiated six human and six chimpanzee induced pluripotent stem cell lines (iPSCs) into mesenchymal stem cells (MSCs) and subsequently into osteogenic cells (bone cells). We validated differentiation using standard methods and collected single-cell RNA sequencing data from over 100,000 cells across multiple samples and replicates at each stage of differentiation. While most genes that we examined display conserved patterns of expression across species, hundreds of genes are differentially expressed (DE) between humans and chimpanzees within and across stages of osteogenic differentiation. Some of these interspecific DE genes show functional enrichments relevant in skeletal tissue trait development. Moreover, topic modeling indicates that interspecific gene programs become more pronounced as cells mature. Overall, we propose that this in vitro model can be used to identify interspecific regulatory differences that may have contributed to skeletal trait differences between species.Author SummaryPrimates display a range of skeletal morphologies and susceptibilities to skeletal diseases, but the molecular basis of these phenotypic differences is unclear. Studies of gene expression variation in primate skeletal tissues are extremely restricted due to the ethical and practical challenges associated with collecting samples. Nevertheless, the ability to study gene regulation in primate skeletal tissues is crucial for understanding how the primate skeleton has evolved. We therefore developed a comparative primate skeletal cell culture model that allows us to access a spectrum of human and chimpanzee cell types as they differentiate from stem cells into bone cells. While most gene expression patterns are conserved across species, we also identified hundreds of differentially expressed genes between humans and chimpanzees within and across stages of differentiation. We also classified cells by osteogenic stage and identified additional interspecific differentially expressed genes which may contribute to skeletal trait differences. We anticipate that this model will be extremely useful for exploring questions related to gene regulation variation in primate bone biology and development.

Response of normal and osteoporotic human bone cells to mechanical stress in vitro

1998 ◽  
Vol 274 (6) ◽  
pp. E1113-E1120 ◽  
Author(s):  
Jozien G. H. Sterck ◽  
Jenneke Klein-Nulend ◽  
Paul Lips ◽  
Elisabeth H. Burger
Keyword(s):  
Nitric Oxide ◽  
Mechanical Stress ◽  
Cell Cultures ◽  
Bone Cells ◽  
Bone Cell ◽  
Human Bone ◽  
Animal Bone ◽  
Bone Cell Cultures

Bone adapts to mechanical stress, and bone cell cultures from animal origin have been shown to be highly sensitive to mechanical stress in vitro. In this study, we tested whether bone cell cultures from human bone biopsies respond to stress in a similar manner as animal bone cells and whether bone cells from osteoporotic patients respond similarly to nonosteoporotic donors. Bone cell cultures were obtained as outgrowth from collagenase-stripped trabecular bone fragments from 17 nonosteoporotic donors between 7 and 77 yr of age and from 6 osteoporotic donors between 42 and 72 yr of age. After passage, the cells were mechanically stressed by treatment with pulsating fluid flow (PFF; 0.7 ± 0.03 Pa at 5 Hz for 1 h) to mimic the stress-driven flow of interstitial fluid through the bone canaliculi, which is likely the stimulus for mechanosensation in bone in vivo. Similar to earlier studies in rodent and chicken bone cells, the bone cells from nonosteoporotic donors responded to PFF with enhanced release of prostaglandin E2(PGE2) and nitric oxide as well as a reduced release of transforming growth factor-β (TGF-β). The upregulation of PGE2 but not the other responses continued for 24 h after 1 h of PFF treatment. The bone cells from osteoporotic donors responded in a similar manner as the nonosteoporotic donors except for the long-term PGE2 release. The PFF-mediated upregulation of PGE2 release during 24 h of postincubation after 1 h of PFF was significantly reduced in osteoporotic patients compared with six age-matched controls as well as with the whole nonosteoporotic group. These results indicate that enhanced release of PGE2 and nitric oxide, as well as reduced release of TGF-β, is a characteristic response of human bone cells to fluid shear stress, similar to animal bone cells. The results also suggest that bone cells from osteoporotic patients may be impaired in their long-term response to mechanical stress.

Sign in / Sign up

Export Citation Format

Share Document