scholarly journals Study of Endochondral Ossification in Human Fetalcartilage Anlagen of Metacarpals: Comparative Morphology of Mineral Deposition in Cartilage and in the Periosteal Bone Matrix

2018 ◽  
Vol 301 (4) ◽  
pp. 571-580 ◽  
Author(s):  
Ugo E. Pazzaglia ◽  
Marcella Reguzzoni ◽  
Francesca Pagani ◽  
Valeria Sibilia ◽  
Terenzio Congiu ◽  
...  
1993 ◽  
Vol 41 (2) ◽  
pp. 193-203 ◽  
Author(s):  
P Bianco ◽  
M Riminucci ◽  
G Silvestrini ◽  
E Bonucci ◽  
J D Termine ◽  
...  

Bone sialoprotein (BSP), a bone matrix-enriched glycoprotein containing the Arg-Gly-Asp (RGD) motif and endowed with cell binding properties, was localized in osteoblasts and early bone matrix of developing rat bone at the ultrastructural level. Preliminary light microscopic observations indicated that intracellular labelling was restricted to a paranuclear dot corresponding to the "negative Golgi image" of classical histology. The same pattern was observed whether antisera against the fully glycosylated protein or a peptide antiserum to a stretch of amino acids in human BSP sequence were employed. At the EM level, we obtained labeling over the Golgi area of osteoblasts but not over the rER. The labeling was concentrated over distensions of the trans Golgi and over pro-secretory granules. In the matrix, BSP was distributed in a non-random manner. The label was concentrated over spherical aggregates of finely fibrillar material corresponding to the sites of early mineral deposition (so-called "mineralization nodules"). Such BSP-positive foci were seen both close to and away from the cell surface. The predominant association of BSP with Golgi and post-Golgi secretory structures and its absence from rER, as well as the reproducibility of the same pattern of localization with different antisera, might indicate a slow transit of the protein through the Golgi, not necessarily associated with protein glycosylation.


Development ◽  
1996 ◽  
Vol 122 (10) ◽  
pp. 3151-3162 ◽  
Author(s):  
A.R. Hayman ◽  
S.J. Jones ◽  
A. Boyde ◽  
D. Foster ◽  
W.H. Colledge ◽  
...  

Mature osteoclasts specifically express the purple, band 5 isozyme (Acp 5) of tartrate-resistant acid phosphatase, a binuclear metalloenzyme that can generate reactive oxygen species. The function of Acp 5 was investigated by targeted disruption of the gene in mice. Animals homozygous for the null Acp 5 allele had progressive foreshortening and deformity of the long bones and axial skeleton but apparently normal tooth eruption and skull plate development, indicating a role for Acp 5 in endochondral ossification. Histomorphometry and mineralization density analysis of backscattered electron imaging revealed widened and disorganized epiphyseal growth plates with delayed mineralization of cartilage in 6- to 8-week-old mutant mice. The membrane bones of the skull showed increased density at all ages examined, indicating defective osteoclastic bone turnover. Increased mineralization density was observed in the long bones of older animals which showed modelling deformities at their extremities: heterozygotes and homozygous Acp 5 mutant mice had tissue that was more mineralized and occupied a greater proportion of the bone in all regions. Thus the findings reflect a mild osteopetrosis due to an intrinsic defect of osteoclastic modelling activity that was confirmed in the resorption pit assay in vitro. We conclude that this bifunctional metalloprotein of the osteoclast is required for normal mineralization of cartilage in developing bones; it also maintains integrity and turnover of the adult skeleton by a critical contribution to bone matrix resorption.


1993 ◽  
Vol 06 (01) ◽  
pp. 21-28 ◽  
Author(s):  
Elaine Forell ◽  
Barbara Powers ◽  
J. Johnson ◽  
Mary Cooper ◽  
St. J. Withrow ◽  
...  

SummaryThe osteoinductive capacity of canine demineralized bone matrix (DBM), implanted in epaxial muscle sites of athymic rats, was evaluated using calcium content and histomorphometry at two, four and six weeks after implantation. Results of this study confirm that DBM, derived from canine sources, does possess significant osteoinductive ability since histological examination revealed the presence of new cartilage, bone, or both, at 21/24 implantation sites. The osteogenesis induced by canine DBM continued as an active, cumulative process throughout the six week investigation period. The mean percentage of total induced osteogenic components including new, live cartilage, woven bone, lamellar bone and bone marrow cellular elements, was significantly greater after six weeks than after two weeks of implantation (p <0.01). Comparison of histomorphometric point counts at two, four and six weeks of implantation supported the conclusion that bone for mation as induced by canine DBM, proceeds primarily via an endochondral ossification pathway. Although the amount of calcium deposited in tissues harvested from DBM implanted sites tended to increase as implantation time lengthened, there was not a statistically significant correlation between calcium content and the level of osteogenic activity seen histologically (r = 0.32, p = 0.13).The osteoinductive capacity of canine demineralized bone matrix (DBM), implanted in ep-axial muscle sites of athymic rats, was evaluated using calcium content and histomorphometry at two, four and six weeks after implantation. Results of this investigation confirm that DBM, derived from canine sources, does possess significant osteo-inductive ability and that bone formation proceeds primarily via a pathway of endochondral ossification.


2020 ◽  
Vol 21 (2) ◽  
pp. 677 ◽  
Author(s):  
Hiroaki Takebe ◽  
Nazmus Shalehin ◽  
Akihiro Hosoya ◽  
Tsuyoshi Shimo ◽  
Kazuharu Irie

Bone fracture healing involves the combination of intramembranous and endochondral ossification. It is known that Indian hedgehog (Ihh) promotes chondrogenesis during fracture healing. Meanwhile, Sonic hedgehog (Shh), which is involved in ontogeny, has been reported to be involved in fracture healing, but the details had not been clarified. In this study, we demonstrated that Shh participated in fracture healing. Six-week-old Sprague–Dawley rats and Gli-CreERT2; tdTomato mice were used in this study. The right rib bones of experimental animals were fractured. The localization of Shh and Gli1 during fracture healing was examined. The localization of Gli1 progeny cells and osterix (Osx)-positive cells was similar during fracture healing. Runt-related transcription factor 2 (Runx2) and Osx, both of which are osteoblast markers, were observed on the surface of the new bone matrix and chondrocytes on day seven after fracture. Shh and Gli1 were co-localized with Runx2 and Osx. These findings suggest that Shh is involved in intramembranous and endochondral ossification during fracture healing.


1976 ◽  
Vol 69 (3) ◽  
pp. 557-572 ◽  
Author(s):  
A H Reddi ◽  
W A Anderson

Transplantation of collagenous matrix from the rat diaphyseal bone to subcutaneous sites resulted in new bone formation by an endochondral sequence. Functional bone marrow develops within the newly formed ossicle. On day 1, the implanted matrix was a discrete conglomerate with fibrin clot and polymorphonuclear leukocytes. By day 3, the leukocytes disappeared, and this event was followed by migration and close apposition of fibroblast cell surface to the collagenous matrix. This initial matrix-membrane interaction culminated in differentiation of fibroblasts to chondroblasts and osteoblasts. The calcification of the hypertrophied chondrocytes and new bone formation were correlated with increased alkaline phosphatase activity and 45Ca incorporation. The ingrowth of capillaries on day 9 resulted in chondrolysis and osteogenesis. Further remodelling of bony trabeculae by osteoclasts resulted in an ossicle of cancellous bone. This was followed by emergence of extravascular islands of hemocytoblasts and their differentiation into functional bone marrow with erythropoietic and granulopoietic elements and megakaryocytes in the ossicle. The onset and maintenance of erythropoiesis in the induced bone marrow were monitored by 59Fe incorporation into protein-bound heme. These findings imply a role for extracellular collagenous matrix in cell differentiation.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
L. Masi ◽  
◽  
S. Ferrari ◽  
M. K. Javaid ◽  
S. Papapoulos ◽  
...  

Abstract Background Bone tissue represents a large systemic compartment of the human body, with an active metabolism, that controls mineral deposition and removal, and where several factors may play a role. For these reasons, several non-skeletal diseases may influence bone metabolism. It is of a crucial importance to classify these disorders in order to facilitate diagnosis and clinical management. This article reports a taxonomic classification of non-skeletal rare congenital disorders, which have an impact on bone metabolism Methods The International Osteoporosis Foundation (IOF) Skeletal Rare Diseases Working Group (SRD-WG), comprised of basic and clinical scientists, has decided to review the taxonomy of non-skeletal rare disorders that may alter bone physiology. Results The taxonomy of non-skeletal rare congenital disorders which impact bone comprises a total of 6 groups of disorders that may influence the activity of bone cells or the characteristics of bone matrix. Conclusions This paper provides the first comprehensive taxonomy of non-skeletal rare congenital disorders with impact on bone physiology.


1987 ◽  
Vol 105 (6) ◽  
pp. 2569-2579 ◽  
Author(s):  
E J Mackie ◽  
I Thesleff ◽  
R Chiquet-Ehrismann

The tissue distribution of the extracellular matrix glycoprotein, tenascin, during cartilage and bone development in rodents has been investigated by immunohistochemistry. Tenascin was present in condensing mesenchyme of cartilage anlagen, but not in the surrounding mesenchyme. In fully differentiated cartilages, tenascin was only present in the perichondrium. In bones that form by endochondral ossification, tenascin reappeared around the osteogenic cells invading the cartilage model. Tenascin was also present in the condensing mesenchyme of developing bones that form by intramembranous ossification and later was present around the spicules of forming bone. Tenascin was absent from mature bone matrix but persisted on periosteal and endosteal surfaces. Immunofluorescent staining of wing bud cultures from chick embryos showed large amounts of tenascin in the forming cartilage nodules. Cultures grown on a substrate of tenascin produced more cartilage nodules than cultures grown on tissue culture plastic. Tenascin in the culture medium inhibited the attachment of wing bud cells to fibronectin-coated substrates. We propose that tenascin plays an important role in chondrogenesis by modulating fibronectin-cell interactions and causing cell rounding and condensation.


2020 ◽  
Vol 318 (1) ◽  
pp. C111-C124 ◽  
Author(s):  
Paul H. Schlesinger ◽  
Harry C. Blair ◽  
Donna Beer Stolz ◽  
Vladimir Riazanski ◽  
Evan C. Ray ◽  
...  

Bone differs from other connective tissues; it is isolated by a layer of osteoblasts that are connected by tight and gap junctions. This allows bone to create dense lamellar type I collagen, control pH, mineral deposition, and regulate water content forming a compact and strong structure. New woven bone formed after degradation of mineralized cartilage is rapidly degraded and resynthesized to impart structural order for local bone strength. Ossification is regulated by thickness of bone units and by patterning via bone morphogenetic receptors including activin, other bone morphogenetic protein receptors, transforming growth factor-β receptors, all part of a receptor superfamily. This superfamily interacts with receptors for additional signals in bone differentiation. Important features of the osteoblast environment were established using recent tools including osteoblast differentiation in vitro. Osteoblasts deposit matrix protein, over 90% type I collagen, in lamellae with orientation alternating parallel or orthogonal to the main stress axis of the bone. Into this organic matrix, mineral is deposited as hydroxyapatite. Mineral matrix matures from amorphous to crystalline hydroxyapatite. This process includes at least two-phase changes of the calcium–phosphate mineral as well as intermediates involving tropocollagen fibrils to form the bone composite. Beginning with initiation of mineral deposition, there is uncertainty regarding cardinal processes, but the driving force is not merely exceeding the calcium-phosphate solubility product. It occurs behind a epithelial-like layer of osteoblasts, which generate phosphate and remove protons liberated during calcium-phosphate salt deposition. The forming bone matrix is discontinuous from the general extracellular fluid. Required adjustment of ionic concentrations and water removal from bone matrix are important details remaining to be addressed.


2018 ◽  
Vol 315 (4) ◽  
pp. C587-C597 ◽  
Author(s):  
Harry C. Blair ◽  
Quitterie C. Larrouture ◽  
Irina L. Tourkova ◽  
Li Liu ◽  
Jing Hao Bian ◽  
...  

Osteoblasts secrete collagen and isolate bone matrix from extracellular space. In the matrix, alkaline phosphatase generates phosphate that combines with calcium to form mineral, liberating 8 H+ per 10 Ca+2 deposited. However, pH-dependent hydroxyapatite deposition on bone collagen had not been shown. We studied the dependency of hydroxyapatite deposition on type I collagen on pH and phosphate by surface plasmon resonance in 0–5 mM phosphate at pH 6.8–7.4. Mineral deposition saturated at <1 mM Ca2+ but was sensitive to phosphate. Mineral deposition was reversible, consistent with amorphous precipitation; stable deposition requiring EDTA removal appeared with time. At pH 6.8, little hydroxyapatite deposited on collagen; mineral accumulation increased 10-fold at pH 7.4. Previously, we showed high expression Na+/H+ exchanger (NHE) and ClC transporters in osteoblasts. We hypothesized that, in combination, these move protons across osteoblasts to the general extracellular space. We made osteoblast membrane vesicles by nitrogen cavitation and used acridine orange quenching to characterize proton transport. We found H+ transport dependent on gradients of chloride or sodium, consistent with apical osteoblast ClC family Cl−,H+ antiporters and basolateral osteoblast NHE family Na+/H+ exchangers. Little, if any, active H+ transport, supported by ATP, occurred. Major transporters include cariporide-sensitive NHE1 in basolateral membranes and ClC3 and ClC5 in apical osteoblast membranes. The mineralization inhibitor levamisole reduced bone formation and expression of alkaline phosphatase, NHE1, and ClC5. We conclude that mineral deposition in bone collagen is pH-dependent, in keeping with H+ removal by Cl−,H+ antiporters and Na+/H+-exchangers. Periodic orientation hydroxyapatite is organized on type I collagen-coiled coils.


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