scholarly journals Isolation and characterization of proteoglycans synthesized by mouse osteoblastic cells in culture during the mineralization process

1990 ◽  
Vol 266 (1) ◽  
pp. 15-24 ◽  
Author(s):  
Y Takeuchi ◽  
T Matsumoto ◽  
E Ogata ◽  
Y Shishiba
Keyword(s):  
Core Protein ◽  
Chondroitin Sulphate ◽  
Heparan Sulphate ◽  
Osteoblastic Cell ◽  
Guanidinium Chloride ◽  
Mineralization Process ◽  
Osteoblastic Cell Line ◽  
Isolation And Characterization

Proteoglycans in mineralized (0.5 M-EDTA/4 M-guanidinium chloride-extractable) and non-mineralized (4 M-guanidinium chloride-extractable) matrices synthesized by a mouse osteoblastic-cell line MC3T3-E1 were characterized at different phases of mineralization in vitro. Cell cultures were labelled with [35S]sulphate and either [3H]glucosamine or 3H-labelled amino acids. At the mineralization phase a large majority of proteoglycans were extracted with 4 M-guanidinium chloride (G extract), and at least five species of labelled proteoglycans were identified; dermatan sulphate proteoglycans (DSPG), apparent Mr approx. 120,000 and 70,000), heparan sulphate proteoglycans (HSPG, apparent Mr approx. 200,000 and 120,000) and DS chains with very little core protein. DSPGs weakly bound to an octyl-Sepharose CL-4B column and HSPGs bound more tightly, whereas DS chains did not bind to the column. Amounts of labelled proteoglycans extracted with 0.5 M-EDTA/4 M-guanidinium chloride (EDTA extract) were much less than those in G extract. Although the predominant species in the EDTA extract were comparable with the DS or DSPGs in the G extract, none of them bound to octyl-Sepharose CL-4B, indicating their lack of hydrophobicity. At the nonmineralizing phase a large chondroitin sulphate proteoglycan (Mr greater than 600,000) was found in the matrix in addition to the five proteoglycan species similar to those at the mineralization phase. Although DS chains at the early phase were similar in size to those at the mineralization phase, the ratio of 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-4-O-sulpho-D-galactose to 2-acetamido-2-deoxy-3-O-(beta-D-gluculo-4-enepyranosyluronic acid)-6-O-sulpho-D-galactose was less than that at the mineralization phase. These results agree with those of previous studies performed in vivo and suggest that alteration in the synthesis of proteoglycans is involved in the mineralization process. They also suggest that at the osteoblastic mineralization front proteoglycans undergo partial degradation and lose their hydrophobicity.

scholarly journals β-d-xylosides and their analogues as artificial initiators of glycosaminoglycan chain synthesis. Aglycone-related variation in their effectiveness in vitro and in ovo

1987 ◽  
Vol 241 (2) ◽  
pp. 591-601 ◽  
Author(s):  
M Sobue ◽  
H Habuchi ◽  
K Ito ◽  
H Yonekura ◽  
K Oguri ◽  
...  
Keyword(s):  
Growth Rate ◽  
Core Protein ◽  
Chondroitin Sulphate ◽  
Average Length ◽  
Heparan Sulphate ◽  
Carbon Number ◽  
Average Chain Length ◽  
In Ovo ◽  
Ability To Act

A series of aryl and alkyl O-beta-D-xylosides and their analogues with S, NH or CH2 in the glycosidic linkage were prepared and examined for their ability to act as artificial chain initiators of chondroitin (dermatan) sulphate synthesis in embryonic chick cartilage, foetal rat skin and 6-week-old-rat aorta under conditions where normal protein-core synthesis was inhibited by cycloheximide. For all these tissues in culture, phenyl O-beta-D-xyloside and phenyl beta-D-thioxyloside were clearly more effective than the corresponding N-xyloside and homo-C-xyloside. Introduction of a carboxy group to the para position of their aglycone yielded derivatives with far lower initiator activity. In a concentration range lower than 0.1 mM, the effectiveness of alkyl beta-D-thioxyloside was greatly influenced by the carbon number (n) of the alkyl group and was at a maximum at n = 7 or 8 for the cartilage, at n = 5 for the skin and at n = 4 for the aorta. In the beta-xyloside-treated cartilages, the average length of newly formed chondroitin sulphate chains reflected the chain-initiator activity of added xyloside, i.e. the higher the initiator activity, the shorter the average chain length. In the skin and aorta, none of the drugs could relieve the inhibition of heparan sulphate synthesis caused by cycloheximide. Fertilized hens' eggs were each injected on day 9 with 9.2 mumol of beta-xyloside and the skeletal systems of embryos were examined a week later. The embryos treated with beta-xylosides of relatively high initiator activity showed a 30-40% decrease in the overall growth rate of skeletons, whereas those treated with beta-xylosides of low initiator activity showed little or no decrease in the growth rate. The results are consistent with the notion that the observed change in skeletal morphology results mainly, if not completely, from beta-xyloside-induced synthesis of core-protein-free chondroitin sulphate, and further suggest that a procedure employing a series of beta-xyloside homologues with various initiator activities will furnish an easily applied criterion on which to test the specificity of xyloside action on biological processes.

scholarly journals Renal glomerular proteoglycans. An investigation of their synthesis in vivo using a technique for fixation in situ

1988 ◽  
Vol 251 (2) ◽  
pp. 411-418 ◽  
Author(s):  
L A Beavan ◽  
M Davies ◽  
R M Mason
Keyword(s):  
Basement Membrane ◽  
Glomerular Basement Membrane ◽  
Membrane Fraction ◽  
Chondroitin Sulphate ◽  
Heparan Sulphate ◽  
Basement Membranes ◽  
Chondroitin Sulphate Proteoglycans

Newly synthesized rat glomerular [35S]proteoglycans were labelled in vivo after injecting Na2[35S]SO4 intraperitoneally. At the end of the labelling period (7 h) the kidneys were perfused in situ with 0.01% (w/v) cetylpyridinium chloride. This fixed proteoglycans in the tissue and increased their recovery 2-3-fold during subsequent isolation of glomeruli from the renal cortex. The glomeruli were fractionated by a modified osmotic lysis and detergent extraction procedure [Meezan, Brendel, Hjelle & Carlson (1978) in The Biology and Chemistry of Basement Membranes (Kefalides, N.A., ed.), Academic Press, New York; Kanwar & Farquhar (1979) Proc. Natl. Acad. Sci. U.S.A. 76, 4493-4497] to obtain a basement membrane preparation. The proteoglycans released at each stage of the procedure were characterized using DEAE-Sephacel ion-exchange chromatography, chondroitinase ABC and HNO2 digestion and Sepharose CL-4B gel-permeation chromatography. About 85% of the [35S]proteoglycans synthesized were of the heparan sulphate variety, the remainder being chondroitin sulphate proteoglycans. Three sizes of heparan sulphate proteoglycans were identified. The largest (HS1, Kav. 0.47) accounts for 44% of the total extractable heparan sulphates. About one third of HS1 were extracted from the glomerular basement-membrane fraction with 8 M-urea and 4 M-guanidine hydrochloride but the remainder were released from the glomerulus during preparation of the fraction. The two smaller molecules (HS2, Kav. 0.56 and HS3, Kav. 0.68) accounted for 27% and 28% of the extractable heparan sulphate respectively and were not associated with the basement membrane fraction. HS1, HS2 and HS3 were also isolated from non-fixed glomeruli labelled in vivo but with much lower recovery. In glomeruli labelled in vitro, heparan sulphate accounted for only 35% of the proteoglycans, the remainder being of the chondroitin sulphate type. Proteoglycans similar to HS1, HS2 and HS3 were present in glomeruli labelled in vitro but, in addition, a large, highly charged heparan sulphate (HS1a) was extracted from the glomerular basement-membrane fraction of these glomeruli. It accounted for 6% of the total heparan sulphate.

scholarly journals Anti-Osteoporotic Effects of Combined Extract of Lycii Radicis Cortex and Achyranthes japonica in Osteoblast and Osteoclast Cells and Ovariectomized Mice

Nutrients ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2716 ◽  
Author(s):  
Eunkuk Park ◽  
Jeonghyun Kim ◽  
Subin Yeo ◽  
Eunguk Lim ◽  
Chun Whan Choi ◽  
...  
Keyword(s):  
Bone Loss ◽  
Osteoclast Differentiation ◽  
Osteoporotic Bone ◽  
Osteoblastic Cell ◽  
Mouse Bone Marrow ◽  
Osteoblastic Cell Line ◽  
Ovariectomized Mice ◽  
Achyranthes Japonica

Osteoporosis is characterized by low bone density and quality with high risk of bone fracture. Here, we investigated anti-osteoporotic effects of natural plants (Lycii Radicis Cortex (LRC) and Achyranthes japonica (AJ)) in osteoblast and osteoclast cells in vitro and ovariectomized mice in vivo. Combined LRC and AJ enhanced osteoblast differentiation and mineralized bone-forming osteoblasts by the up-regulation of bone metabolic markers (Alpl, Runx2 and Bglap) in the osteoblastic cell line MC3T3-E1. However, LRC and AJ inhibited osteoclast differentiation of monocytes isolated from mouse bone marrow. In vivo experiments showed that treatment of LRC+AJ extract prevented OVX-induced trabecular bone loss and osteoclastogenesis in an osteoporotic animal model. These results suggest that LRC+AJ extract may be a good therapeutic agent for the treatment and prevention of osteoporotic bone loss.

scholarly journals Absence of keratan sulphate from skeletal tissues of mouse and rat

1985 ◽  
Vol 228 (2) ◽  
pp. 443-450 ◽  
Author(s):  
G Venn ◽  
R M Mason
Keyword(s):  
Monoclonal Antibody ◽  
Degradation Products ◽  
Chondroitin Sulphate ◽  
Lumbar Disc ◽  
Heparan Sulphate ◽  
Costal Cartilage ◽  
Animal Experiments ◽  
Keratan Sulphate

The absence of keratan sulphate synthesis from skeletal tissues of young and mature mice and rats has been confirmed by (1) analysis of specific enzyme degradation products of newly synthesized glycosaminoglycans, and (2) immunohistochemistry and radioimmunoassay using a monoclonal antibody directed against keratan sulphate. Approx. 98% of the [35S]glycosaminoglycans synthesized in vivo by mouse and rat costal cartilage, and all of those of lumbar disc, are chondroitin sulphate. The remainder in costal cartilage were identified as heparan sulphate in mature rats. In contrast, [35S]glycosaminoglycans synthesized by cornea of both species comprised both chondroitin sulphate and keratan sulphate. In mice keratan sulphate accounted for 12-25% and in rats 40-50% of the total [35S]glycosaminoglycans, depending on the age of the animal. Experiments in vitro with organ culture of cartilage and cornea confirm these results. Absence of keratan sulphate from mouse costal cartilage and lumbar disc D1-proteoglycans was corroborated by inhibition radioimmunoassay with the monoclonal antibody MZ15 and by lack of staining for keratan sulphate in indirect immunofluorescence studies using the same antibody.

scholarly journals Characterization of proteoglycans associated with mouse splenic AA amyloidosis

1994 ◽  
Vol 303 (2) ◽  
pp. 663-670 ◽  
Author(s):  
T Stenstad ◽  
J H Magnus ◽  
G Husby
Keyword(s):  
Amyloid Fibrils ◽  
Core Protein ◽  
Chondroitin Sulphate ◽  
Heparan Sulphate ◽  
Pulse Labelling ◽  
Sulphate Proteoglycan ◽  
Amyloid Deposits ◽  
Amyloid Fibril Formation

We here report for the first time on the chemical characteristics of proteoglycans associated with mouse splenic reactive AA amyloid. Amyloid was induced in CBA/J mice by two different procedures; conventional casein treatment and by employing Freund's complete adjuvant, accelerated by Trypan Blue. Pulse-labelling was employed at distinct stages during amyloid development, followed by [35S]proteoglycan characterization of organ extracts. Repetitive 35S injections were also administered during the phase where amyloid deposition occurred most rapidly. Proteoglycans were extracted with guanidine in the presence of protease inhibitors and purified. The results showed that the production of proteoglycans is dramatically enhanced during amyloidogenesis, the glycosaminoglycan and proteoglycan accumulation being not only dependent on alterations in proteoglycan catabolism, but rather on increased synthesis. The increment could be demonstrated even at the stage before microscopic detection of amyloid deposits, clearly suggesting that the upregulation of proteoglycan expression precedes amyloid fibril formation. Two major proteoglycans were found to accumulate in advanced splenic amyloid; one a heparan sulphate proteoglycan of approx. 200 kDa with a core protein of 70 kDa, the other a chondroitin sulphate proteoglycan of smaller size. Moreover, free dermatan sulphate chains seemed to specifically accumulate in the organs during amyloid fibrillogenesis. We suggest that free glycosaminoglycans may be a specific feature of amyloidosis and that different proteoglycans and glycosaminoglycans play a role in formation and stabilization of amyloid fibrils in vivo.

PTH Stimulates Osteoblastic VEGF-A Production and Remodels Bone Marrow Micro-Endothelial Structures

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 722-722
Author(s):  
Julianne N Smith ◽  
Jonathan M Weber ◽  
Laura M Calvi
Keyword(s):  
Bone Marrow ◽  
Extracellular Matrix ◽  
Conflicts Of Interest ◽  
Fold Change ◽  
Osteoblastic Cells ◽  
Osteoblastic Cell ◽  
Osteoblastic Cell Line ◽  
Hematopoietic Stem

Abstract Abstract 722 In their niches within the bone marrow (BM) microenvironment, hematopoietic stem cells (HSCs) interact with a number of other cellular and molecular factors that can affect their regulation. We previously demonstrated that activation of osteoblasts (OBs) by intermittent Parathyroid Hormone (PTH) stimulation or by expression of a constitutively active PTH receptor (Col1caPTH1R mice, hereafter referred to as TG) expands HSCs with long term repopulating ability. PTH treatment has also been found to improve survival after BM injuries that severely disrupt the hematopoietic system as well as the BM vasculature; however the mechanism for this effect is unknown. Osteoblastic cells respond directly to PTH administration, whereas HSCs lack expression of the PTH1R, indicating that PTH-mediated HSC expansion occurs through the BM microenvironment. Both endosteal osteoblastic cells and the vasculature constitute HSC niches within the BM. Intermittent PTH exerts an anabolic effect on bone, expanding trabecular bone and bone-lining stromal cells. New vessel formation is required for adult bone remodeling. To test if PTH also increases the BM vasculature, we treated mice with an intensive regimen of systemic PTH that expanded hematopoietic stem and progenitor cells (HSPCs) and analyzed hindlimb histology as well as BM cell immunophenotype. In the tibial and femoral metaphyseal region, PTH increased microvessels (167 ± 18.1 vs 348 ± 39.3 microvessels/hindlimb, n=5 mice per group, p=0.0030) and vascular area ((mm2): 0.135 ± 0.0194 vs 0.281 ± 0.00951, n=5 mice per group, p=0.0001) measured by histomorphometry. PTH also increased the frequency of PECAM+ BM endothelial cells (0.0935 ± 0.0173 vs 0.196 ± 0.0172, n=4–5 mice per group, p=0.0043) measured flow cytometrically. To determine if PTH increases osteoblast-derived angiogenic signals, mouse calvarial MC3T3 cells were treated with PTH(1-34) at various stages of osteoblastic maturation. Differentiation of MC3T3 cells did not affect baseline Vegfa expression. PTH strongly induced total Vegfa expression in day 7 cells at two hours, an effect that peaked at six hours (3.83 ± 1.76 vs 50.7 ± 9.72 fold change above baseline, n=3, p=0.0090) and was sustained 24 hours after treatment. The magnitude of the effect increased throughout osteoblastic differentiation. In vitro PTH also increased levels of secreted VEGF-A protein at corresponding time points (VEGF-A(pg/mL): 43.4 ± 2.27 vs 464 ± 24.2, n=3, p<0.0001). Similarly, PTH induced Vegfa expression two hours post-stimulation in a second osteoblastic cell line, derived from rat osteosarcoma (1.133 ± 0.2963 vs 8.500 ± 1.320 fold change above baseline, n=3, p=0.0055). Vegfa pre-mRNA comprises eight exons that undergo alternative splicing to form variants encoding several VEGF-A isoforms. These isoforms differ functionally primarily due to their varying heparan-binding affinity. Specifically, VEGF189 remains mostly cell and matrix-associated due to its interactions with heparan sulfate proteoglycans in extracellular matrix and on cell surfaces. Because PTH stimulation dramatically increases extracellular matrix and bone volume, expression of the splice variant encoding matrix-associated VEGF189 was assayed in PTH-stimulated MC3T3 cells. PTH strongly increased expression of the VEGF189-encoding variant six hours after treatment of maturing MC3T3 cells (1.70 ± 1.100 vs 113 ± 25.1, n=3, p=0.0416), suggesting that PTH may favor expression of a more highly localized VEGF-A isoform. Analysis of BM plasma revealed that soluble VEGF-A levels were significantly decreased both in TG mice (VEGF-A(pg/mL): 74.2 ± 7.05 vs 44.0 ± 3.67, n=3-5 mice per group, p=0.0054) and in mice treated systemically with PTH (VEGF-A(pg/mL): 105 ± 6.62 vs 78.6 ± 4.95, n=9 mice per group, two independent experiments, p=0.0054), while serum VEGF-A levels were unchanged. Since PTH strongly stimulates osteoblastic expression of matrix-bound VEGF-A but less soluble VEGF-A is detected in the BM during PTH stimulation in vivo, we speculated that PTH-dependent proangiogenic signals in the BM microenvironment may be highly localized via modulation of Vegfa pre-mRNA splicing in osteoblastic cells. Because the blood perfusion status of BM niches profoundly affects HSPC behavior, these findings may suggest a mechanism by which PTH establishes highly localized niches to instruct the fate of resident HSCs. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Glomerular mesangial cells in vitro synthesize an aggregating proteoglycan immunologically related to versican

1994 ◽  
Vol 302 (1) ◽  
pp. 49-56 ◽  
Author(s):  
G J Thomas ◽  
M T Bayliss ◽  
K Harper ◽  
R M Mason ◽  
M Davies
Keyword(s):  
Mesangial Cell ◽  
Mesangial Cells ◽  
Core Protein ◽  
Chondroitin Sulphate ◽  
Heparan Sulphate ◽  
Gel Chromatography ◽  
Glomerular Mesangial Cells ◽  
Glomerular Cell ◽  
Core Proteins

Recent studies have shown that mesangial cells derived from human adult glomeruli synthesize a number of 35S-labelled proteoglycans including a large chondroitin sulphate proteoglycan (CSPG), two dermatan sulphate proteoglycans (biglycan and decorin) and two heparan sulphate proteoglycans [Thomas, Mason and Davies (1991) Biochem. J. 277, 81-88]. In the present study we have examined the interaction of these proteoglycans with hyaluronan (HA) using associative gel chromatography. Only the large CSPG bound to HA, with 60% of those molecules in the medium and 80% of those in the cell layer being able to interact. Reduction and alkylation, or treatment of the monomer CSPG with proteinases, prevented the formation of aggregates, suggesting that the core protein was involved. The aggregates formed between purified CSPG and HA could be dissociated in the presence of HA-oligosaccharides of at least 10 monosaccharides in length. The inclusion of link protein with CSPG and HA promoted the formation of aggregates. Experiments with 3H-labelled mesangial-cell proteoglycans confirmed that only the large CSPG, with core protein molecular masses of 400 kDa and 500 kDa, interacted with HA. After chondroitin ABC lyase treatment of CSPG isolated from conditioned culture medium, several bands similar to those observed with 3H-labelled core proteins were identified using a polyclonal antiserum that recognizes versican. A monoclonal antibody recognizing the 1-C-6 epitope in the G1 and G2 globular regions of aggrecan did not recognize either mesangial-cell CSPG or bovine aortic versican. Northern-blot analysis confirmed that human mesangial cells express versican. Thus human mesangial large CSPG is a member of the versican family of proteoglycans. The interaction of CSPG and HA within the glomerulus may be important in glomerular cell migration and proliferation.

scholarly journals Extracellular vesicles as mediators and markers of acute organ injury: current concepts

2021 ◽  
Author(s):  
Birte Weber ◽  
Niklas Franz ◽  
Ingo Marzi ◽  
Dirk Henrich ◽  
Liudmila Leppik
Keyword(s):  
Extracellular Vesicles ◽  
Inflammatory Diseases ◽  
Organ Injury ◽  
Isolation And Characterization ◽  
Communication Processes ◽  
Incidence And Mortality ◽  
New Biomarkers ◽  
And Function

AbstractDue to the continued high incidence and mortality rate worldwide, there is a need to develop new strategies for the quick, precise, and valuable recognition of presenting injury pattern in traumatized and poly-traumatized patients. Extracellular vesicles (EVs) have been shown to facilitate intercellular communication processes between cells in close proximity as well as distant cells in healthy and disease organisms. miRNAs and proteins transferred by EVs play biological roles in maintaining normal organ structure and function under physiological conditions. In pathological conditions, EVs change the miRNAs and protein cargo composition, mediating or suppressing the injury consequences. Therefore, incorporating EVs with their unique protein and miRNAs signature into the list of promising new biomarkers is a logical next step. In this review, we discuss the general characteristics and technical aspects of EVs isolation and characterization. We discuss results of recent in vitro, in vivo, and patients study describing the role of EVs in different inflammatory diseases and traumatic organ injuries. miRNAs and protein signature of EVs found in patients with acute organ injury are also debated.

scholarly journals Isolation and characterization of a gene (CBF2) specifying a protein component of the budding yeast kinetochore.

1993 ◽  
Vol 121 (3) ◽  
pp. 513-519 ◽  
Author(s):  
W Jiang ◽  
J Lechner ◽  
J Carbon
Keyword(s):  
Molecular Motors ◽  
Cell Biology ◽  
Budding Yeast ◽  
Isolation And Characterization ◽  
Sequence Homologies ◽  
Binding Factor ◽  
Microtubule Motor

We have cloned and determined the nucleotide sequence of the gene (CBF2) specifying the large (110 kD) subunit of the 240-kD multisubunit yeast centromere binding factor CBF3, which binds selectively in vitro to yeast centromere DNA and contains a minus end-directed microtubule motor activity. The deduced amino acid sequence of CBF2p shows no sequence homologies with known molecular motors, although a consensus nucleotide binding site is present. The CBF2 gene is essential for viability of yeast and is identical to NDC10, in which a conditional mutation leads to a defect in chromosome segregation (Goh, P.-Y., and J. V. Kilmartin, in this issue of The Journal of Cell Biology). The combined in vitro and in vivo evidence indicate that CBF2p is a key component of the budding yeast kinetochore.

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