Abstract:
:Purpose: The osteocyte is considered the major mechanosensor in bone, capable of detecting forces at a cellular level to coordinate bone formation and resorption. The pathology of age-related bone loss, a hallmark of osteoporosis, is attributed in part to impaired osteocyte mechanosensing. However, real-time evidence of the effect of aging on osteocyte responses to mechanical load is lacking. Intracellular calcium (Ca2+) oscillations have been characterized as an early mechanosensitive response in osteocytes in systems of multiple scales and thus can serve as a real-time measure of osteocyte mechanosensitivity. Our objective was to utilize an ex vivo model to investigate potentially altered mechanosensing in the osteocyte network with aging.Methods: Tibiae were explanted from young-adult (5 mo) and aged (22 mo) female mice and incubated with Fluo-8 AM to visualize osteocyte intracellular Ca2+. Whole tibiae were cyclically loaded while in situ osteocyte Ca2+ dynamics were simultaneously imaged with confocal microscopy. Responsive osteocyte percentage and Ca2+ peak characteristics were quantified, as well as signaling synchrony between paired cells in the field of view.Results: Fewer osteocytes responded to mechanical loading in aged mice compared to young-adult and did so in a delayed manner. Osteocytes from aged mice also lacked the well-correlated relationship between Ca2+ signaling synchrony and cell-cell distance exhibited by young-adult osteocytes.Conclusions: We have demonstrated, for the first time, real-time evidence of the diminished mechanosensing and lack of signaling coordination in aged osteocyte networks in tibial explants, which may contribute to pathology of age-induced bone loss.
journal_name
Connect Tissue Resjournal_title
Connective tissue researchauthors
Morrell AE,Robinson ST,Silva MJ,Guo XEdoi
10.1080/03008207.2020.1712377subject
Has Abstractpub_date
2020-05-01 00:00:00pages
389-398issue
3-4eissn
0300-8207issn
1607-8438journal_volume
61pub_type
杂志文章abstract::Oral mandibular epithelium determines the position and number of tooth organs. Cranial neural crest-derived ectomesenchyme provides inductive signals for (i) tooth shape, and (ii) sequential determination and expression of several different epithelial-derived enamel proteins. Inductive signalling follows a precise seq...
journal_title:Connective tissue research
pub_type: 杂志文章,评审
doi:10.3109/03008208909023878
更新日期:1989-01-01 00:00:00
abstract::Scanning electron microscopy and high angle X-ray diffraction were used to define the relationship between collagen and elastin of bovine aortic wall. The diffraction pattern shows on one hand that the broad rings at 4.5 A and 9 A, due to elastin, do not orient on stretching and on the other hand, that the collagen ri...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008207709152610
更新日期:1977-01-01 00:00:00
abstract::To investigate the source of bone brittleness in the disease osteogenesis imperfecta (OI), biomechanical properties have been measured in the femurs from a homozygous (oim/oim) mutant mouse model of OI, its heterozygous littermates, and wild-type animals. The novel technique of ultrasound critical-angle reflectometry ...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008209909005282
更新日期:1999-01-01 00:00:00
abstract::Monoclonal antibodies (mAbs) (4F2 and 7E12) were prepared against heparan sulfate proteoglycan (HSPG) isolated from bovine glomeruli. Enzyme linked immunosorbent assays (ELISA) and immunoblotting demonstrated that the mABs reacted with HSPG. Indirect immunofluorescence (IF) showed that the mAbs stained renal basement ...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008208809019069
更新日期:1988-01-01 00:00:00
abstract::The interaction of sodium dodecyl sulfate with elastin has been studied by complexometric titration. Approximately 1.2 mumoles of protons with a pKapp of 5.45 are taken up by 10 milligrams of insoluble elastin upon the binding of detergent, apparently due to the protonation of normally ionized carboxylate functions in...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008207809152627
更新日期:1978-01-01 00:00:00
abstract::Aseptic loosening remains the primary cause of failure in total joint arthroplasty. Implant-derived particles are thought to be a main cause of osteolysis that leads to the failure. Substance P (SP) immunoreactive nerve fibers have been detected in the periprosthetic membrane of aseptic loose hip prostheses. We isolat...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008207.2013.823953
更新日期:2013-01-01 00:00:00
abstract::Collagenolytic enzymes were quantitated by a method based on spectrophotometry of suspended reconstituted collagen fibrils. To obtain optically stable suspensions it was necessary to perform a short sonication of the aggregated fibrils at 10 degrees C. When fibrils were cleaved with mammalian fibroblast collagenase at...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008209109152442
更新日期:1991-01-01 00:00:00
abstract::Bone sialoprotein (BSP) expression is restricted to cells associated with the mineralization of bones and teeth. We previously identified a homeodomain binding element in a 2.5 kb fragment of the murine Bsp promoter that is required for osteoblast-selective expression in cell culture. To examine the role of this eleme...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:
更新日期:2003-01-01 00:00:00
abstract::This study examines the similarities and differences in the noncollagenous domain (NC1) of type IV collagen from human glomerular basement membrane (hGBM), alveolar basement membrane (hABM), and placenta (hPBM). Following collagenase digestion, NC1 domain was isolated on Bio-Gel A-0.5m or by cation exchange chromatogr...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008209009152156
更新日期:1990-01-01 00:00:00
abstract::Transforming growth factor beta-1 (TGF beta-1) is a multifunctional growth factor that is expressed in numerous cell types. It has been shown to induce secretion of dentin extracellular matrix components associated with primary dentinogenesis and to play a role in tertiary or reparative dentinogenesis. In this study, ...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.1080/03008200290000565
更新日期:2002-01-01 00:00:00
abstract::This study evaluated the effect of short bouts of stretching on the soleus muscle after immobilization, by measuring the birefringence of the intramuscular connective tissue (ICT) and the muscle fiber area. Thirty rats were divided into five groups: the left soleus was immobilized in the shortened position; after immo...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.1080/03008200600995940
更新日期:2006-01-01 00:00:00
abstract::A partially purified BMP preparation was combined with a fibrous glass membrane (FGM) or porous particles of hydroxyapatite (PPHAP), and then implanted subcutaneously into the backs of rats. As a control of these new carriers, a conventional carrier of insoluble bone matrix (IBM) was also used. These new geometrically...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008209509013726
更新日期:1995-01-01 00:00:00
abstract::The critical remembrance of my research activity displays aspects of inconsequence and mental rigidity. Particular probative examples are called to mind. Unpublished observations concerning immortalized dental cells are summarized. As a consequence, if I could start again, I would improve several aspects of my behavio...
journal_title:Connective tissue research
pub_type:
doi:10.1080/03008200290001195
更新日期:2002-01-01 00:00:00
abstract::In the absence of ascorbic acid, confluent human skin fibroblasts incubated in 0.5% serum-supplemented medium had one-third of the level of lysyl hydroxylase activity of cells incubated in media containing high serum concentrations (5-20%). This difference appeared to be due to a decline in the enzyme activity followi...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008208509152396
更新日期:1985-01-01 00:00:00
abstract::Bone morphogenetic proteins (BMPs) are known to promote periodontal tissue regeneration, while noggin inhibits the biological activities of BMP-2, -4, and -7. To investigate the effect of BMPs and noggin gene transfer on cementogenesis, we used cloned murine cementoblasts (OCCM). Cells were transduced using adenovirus...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.1080/03008200490278142
更新日期:2004-01-01 00:00:00
abstract::Scars formed after tendonitis result in altered tissue mechanical properties after injury. The interaction of collagen molecules with decorin affects collagen fibrogenesis, and scar tissue is fragile as a consequence of a large amount of decorin in the scar. We hypothesized that scar formation could be prevented by co...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.1080/03008200590935510
更新日期:2005-01-01 00:00:00
abstract::Sea urchin's teeth from four families of order Echinoida and from orders Temnopleuroida, Arbacioida and Cidaroida were studied with synchrotron X-ray diffraction. The high and very high Mg calcite phases of the teeth, i.e. the first and second stage mineral constituents, respectively, have the same crystallographic or...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008207.2014.923865
更新日期:2014-08-01 00:00:00
abstract::Changes in the structure and organization of collagen fibrils were recently described in the skin of aspartylglycosaminuria patients. The skin of the patients contained a normal amount and distribution of glycosaminoglycans, but the dermatan sulfate of aspartylglycosaminuria skin was more sensitive to chondroitinase A...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008208709005621
更新日期:1987-01-01 00:00:00
abstract:PURPOSE:Treatment of meniscal injury is important for osteoarthritis (OA) prevention. Meniscus cells are divided between inner and outer cells, which have different characteristics and vascularity. We evaluated the effects of hyaluronic acid (HA) on the proliferation and migration of human inner and outer meniscus cell...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.1080/03008207.2018.1465053
更新日期:2019-03-01 00:00:00
abstract::Vascular smooth muscle cells (VSMC)s are characterized by their acute growth inhibition by heparin and heparan sulfates; however, recently the isolation of VSMCs which display greatly diminished sensitivity to the antiproliferative action of heparin have been reported. These heparin resistant (HR) VSMCs have been deri...
journal_title:Connective tissue research
pub_type: 杂志文章,评审
doi:10.3109/03008209809028903
更新日期:1998-01-01 00:00:00
abstract:PURPOSE/AIM:Glutamate is one of the signaling molecules responsible for transmission in the central nervous system. Periodontal ligament (PDL) cells were recently reported to express metabotropic glutamate receptors (mGluRs). However, the functions of mGluR signaling in PDL cells or PDL-related cells remain largely unk...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.1080/03008207.2016.1195826
更新日期:2016-09-01 00:00:00
abstract::The purpose of this study was to investigate overall degradative changes occurring to enamel matrix proteins in small, freeze-dried pieces of rat incisor enamel homogenized and incubated directly for 0-48 hours in a synthetic enamel fluid solution (165 mM total ionic strength with 0.153 mM calcium chloride) versus oth...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008209809023914
更新日期:1998-01-01 00:00:00
abstract::Part of the hyaluronic acid (HA) synthesized in peripheral tissues enters the blood circulation through the lymph. It is rapidly taken up by the endothelial cells in the liver (half-life in blood is 2.5-5.5 minutes) and degraded. Pure primary cultures of liver endothelial cells were obtained by a newly developed techn...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008208609001971
更新日期:1986-01-01 00:00:00
abstract::We previously reported that circulating peripheral blood-borne cells (PBCs) contribute to early-phase meniscal reparative change. Because macrophages and myofibroblasts are important contributors of tissue regeneration, we examined their origin and distribution in the reparative meniscus. Reparative menisci were evalu...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.1080/03008207.2017.1284825
更新日期:2017-11-01 00:00:00
abstract::The small leucine-rich repeat proteoglycans (SLRPs) constitute a group of structurally and functionally related molecules that participate in the organization of the extracellular matrix ECM and have important effects on cell behavior. Osteosarcomas are heterogeneous bone tumors whose common characteristic is the prod...
journal_title:Connective tissue research
pub_type: 杂志文章,评审
doi:10.1080/03008200802147589
更新日期:2008-01-01 00:00:00
abstract::Laminin promotes adhesion of various cell types via multiple interactions with cell surface components. We have used a laminin domain involved in adhesion of melanoma cells, peptide F9 (Charonis et al., J. Cell Biol. 107:1253 [( 1988]), to examine its specific interaction with cell surface components. Cells were surfa...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008209109152435
更新日期:1991-01-01 00:00:00
abstract::The purpose of this investigation is to evaluate enamel thickness in extant and extinct hominoids. The material used in this study spans the evolutionary history of this group, from 20 million years ago to the present. The objectives of this investigation are to test three hypotheses: (1) the Loading Hypothesis: loadi...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008209809023927
更新日期:1998-01-01 00:00:00
abstract::Hyperhomocysteinemia causes connective tissue pathology. Several theories on the mechanism of homocysteine toxicity in connective tissue are reviewed briefly. A possible new mechanism was revealed recently in the discovery of a reaction in which homocysteine thiolactone is converted to mercaptopropionaldehyde. The rea...
journal_title:Connective tissue research
pub_type: 杂志文章,评审
doi:10.1080/03008200801913742
更新日期:2008-01-01 00:00:00
abstract::The binding of highly purified bovine aortic lysyl oxidase to native fibrils of type I collagen has been measured by assay of unbound lysyl oxidase activity in the supernatants of enzyme-collagen mixtures after centrifugation. The apparent binding affinity of lysyl oxidase for native fibrils is quite similar to that f...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008208509015017
更新日期:1985-01-01 00:00:00
abstract::In the early mineralized enamel crystals, ribbon-like crystals appear near the ameloblasts. Some ribbon-like crystals showed helical or spiral structure within restricted environment during the preparation of embryonic bovine specimens for electron microscope. These specimens did not suffer from the cutting damages no...
journal_title:Connective tissue research
pub_type: 杂志文章
doi:10.3109/03008209809017027
更新日期:1998-01-01 00:00:00