scholarly journals Aggrecan core protein of a certain length is protective against hand osteoarthritis

2006 ◽  
Vol 14 (10) ◽  
pp. 1075-1080 ◽  
Author(s):  
O.-P. Kämäräinen ◽  
S. Solovieva ◽  
T. Vehmas ◽  
K. Luoma ◽  
P. Leino-Arjas ◽  
...  
Keyword(s):  
Core Protein ◽  
Hand Osteoarthritis ◽  
Aggrecan Core Protein

scholarly journals Chondrocyte-mediated catabolism of aggrecan: aggrecanase-dependent cleavage induced by interleukin-1 or retinoic acid can be inhibited by glucosamine

1998 ◽  
Vol 335 (1) ◽  
pp. 59-66 ◽  
Author(s):  
John D. SANDY ◽  
Dan GAMETT ◽  
Vivian THOMPSON ◽  
Christie VERSCHAREN
Keyword(s):  
Retinoic Acid ◽  
Core Protein ◽  
Interleukin 1 ◽  
Cartilage Explants ◽  
Biosynthetic Activity ◽  
Fragment Analysis ◽  
Analysis System ◽  
Chondrosarcoma Cell Line ◽  
Bovine Cartilage ◽  
Aggrecan Core Protein

A rat chondrosarcoma cell line and bovine cartilage explants have been used to study the control of aggrecan degradation by chondrocytes treated with interleukin-1 (IL-1) or retinoic acid (RA). Aggrecan fragment analysis with anti-neo-epitope antibodies suggests that aggrecanase (an as yet unidentified enzyme) is the only aggrecan-degrading proteinase active in these cultures. With rat cells, aggrecanase converts the aggrecan core protein into two major G1-domain-bearing products (60 kDa with a C-terminal Glu-373, and 220 kDa with a C-terminal Glu-1459). Both products were quantified on a standardized Western analysis system with a G1-specific antibody. Immunoblots were analysed by scanning densitometry and the sensitivity, linearity and reproducibility of the assay were established. With rat cells the aggrecanase response to IL-1 was optimal at about 2 mM glutamine, but was progressively inhibited at higher concentrations, with about 90% inhibition at 10 mM glutamine. Such inhibition by glutamine was not, however, observed with bovine explants. On the other hand, marked inhibition of aggrecanase-dependent cleavage was observed with both rat cells and bovine explants when d(+)-glucosamine was included at concentrations above 2 mM. Inhibition was apparently not due to cytotoxicity or interference with IL-1 signalling, since biosynthetic activity was not inhibited and inhibition of the aggrecanase response was also obtained when RA was used as the catabolic stimulator. Possible mechanisms for the inhibition of the aggrecanase response by glucosamine in chondrocytes treated with IL-1 or RA are discussed.

scholarly journals Aggrecan, the Primary Weight-Bearing Cartilage Proteoglycan, Has Context-Dependent, Cell-Directive Properties in Embryonic Development and Neurogenesis: Aggrecan Glycan Side Chain Modifications Convey Interactive Biodiversity

Biomolecules ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1244
Author(s):  
Anthony J Hayes ◽  
James Melrose
Keyword(s):  
Embryonic Development ◽  
Core Protein ◽  
Chondroitin Sulphate ◽  
Weight Bearing ◽  
Neural Crest Cell ◽  
Side Chains ◽  
Neural Crest Cell Migration ◽  
Dependent Cell ◽  
Context Dependent ◽  
Aggrecan Core Protein

This review examines aggrecan’s roles in developmental embryonic tissues, in tissues undergoing morphogenetic transition and in mature weight-bearing tissues. Aggrecan is a remarkably versatile and capable proteoglycan (PG) with diverse tissue context-dependent functional attributes beyond its established role as a weight-bearing PG. The aggrecan core protein provides a template which can be variably decorated with a number of glycosaminoglycan (GAG) side chains including keratan sulphate (KS), human natural killer trisaccharide (HNK-1) and chondroitin sulphate (CS). These convey unique tissue-specific functional properties in water imbibition, space-filling, matrix stabilisation or embryonic cellular regulation. Aggrecan also interacts with morphogens and growth factors directing tissue morphogenesis, remodelling and metaplasia. HNK-1 aggrecan glycoforms direct neural crest cell migration in embryonic development and is neuroprotective in perineuronal nets in the brain. The ability of the aggrecan core protein to assemble CS and KS chains at high density equips cartilage aggrecan with its well-known water-imbibing and weight-bearing properties. The importance of specific arrangements of GAG chains on aggrecan in all its forms is also a primary morphogenetic functional determinant providing aggrecan with unique tissue context dependent regulatory properties. The versatility displayed by aggrecan in biodiverse contexts is a function of its GAG side chains.

Hyaluronate degradation as an alternative mechanism for proteoglycan release from cartilage during interleukin-1β-stimulated catabolism

2002 ◽  
Vol 362 (2) ◽  
pp. 473-479 ◽  
Author(s):  
Robert SZTROLOVICS ◽  
Anneliese D. RECKLIES ◽  
Peter J. ROUGHLEY ◽  
John S. MORT
Keyword(s):  
Core Protein ◽  
Cartilage Matrix ◽  
Interleukin 1Β ◽  
Alternative Mechanism ◽  
Human Articular Cartilage ◽  
Link Protein ◽  
Nasal Cartilage ◽  
Fetal Bovine ◽  
Proteoglycan Release ◽  
Aggrecan Core Protein

Data presented previously suggest that release of components of the cartilage matrix, in response to catabolic agents, cannot be accounted for by proteolytic mechanisms alone. In the present study, the release of glycosaminoglycan-containing components from bovine nasal cartilage cultured in the presence of interleukin-1β, and from bovine nasal, fetal bovine epiphyseal and adult human articular cartilage cultured in the presence of retinoic acid, was accompanied by the loss of link protein and hyaluronate into the culture medium. Chromatographic analysis of the released hyaluronate showed it to be markedly reduced in size relative to that extracted from the corresponding tissue. It is proposed that, under stimulation by catabolic agents, two independent, but concurrent, mechanisms act to promote the release of aggrecan from the cartilage matrix. First, proteolytic cleavage of the aggrecan core protein results in the production of glycosaminoglycan-containing fragments that are free to diffuse from the tissue. Secondly, cleavage of hyaluronate renders portions of the proteoglycan aggregate small enough so that complexes of aggrecan (or fragments containing its G1 domain) and link protein are released from the tissue. It is likely that both mechanisms contribute to cartilage metabolism in normal physiology and pathology.

Optimalized transient transfection of chondrogenic primary cell cultures

2010 ◽  
Vol 5 (5) ◽  
pp. 572-584 ◽  
Author(s):  
Tamás Juhász ◽  
Csaba Matta ◽  
Zoltán Mészár ◽  
Georgina Nagy ◽  
Zsolt Szíjgyártó ◽  
...  
Keyword(s):  
Cell Cultures ◽  
Protein Phosphatase ◽  
High Efficiency ◽  
Core Protein ◽  
Transfection Efficiency ◽  
Cartilage Formation ◽  
Transfection Method ◽  
Gfp Fluorescence ◽  
Apoptotic Effects ◽  
Aggrecan Core Protein

AbstractWe aimed to find a transfection method which provides high efficiency with minimal cytotoxic and/or apoptotic effects for gene transfer into multilayer primary chondrogenic cell cultures. The pEGFP-C1 plasmid was introduced into the cell culture and the efficiency of transformation quantified by GFP fluorescence; the resulting nucleofection was effective but resulted in severe apoptosis. Two liposomal reagents designed to allow transfection into adherent cells did not deliver the plasmids sufficiently and cartilage formation did not occur. In addition, a third liposomal compound, recommended for transfection into either adherent or suspension cell cultures, lead to acceptable transfection efficiency but no cartilage formation. When an amphiphilic reagent was used however, there was acceptable transfection efficiency as well as cartilage formation. The viability of the cells which were transfected using the amphiphilic reagent remained unaffected but proliferation was severely diminished, particularly in the presence of GFP. In addition, the amount of cartilage decreased when GFP was expressed, despite unchanged levels of mRNAs of sox9 and aggrecan core protein, factors reflecting on the efficiency of chondrogenesis. Overexpression of both the constitutively active delta and gamma isoforms of catalytic subunit of calcineurin, a protein phosphatase described as a positive regulator of chondrogenesis, decreased protein level of Sox9 and subsequent cartilage formation. In conclusion, we found that amphiphilic reagent applied prior to the adhesion of cells provides a useful means to transfer plasmids to primary differentiating chondrogenic cells.

Localization of the Expression of Type I, II, III Collagen, and Aggrecan Core Protein Genes in Developing Human Articular Cartilage

Matrix ◽  
1992 ◽  
Vol 12 (3) ◽  
pp. 221-232 ◽  
Author(s):  
Isabelle Treilleux ◽  
Frederic Mallein-Gerin ◽  
Dominique Le Guellec ◽  
Daniel Herbage
Keyword(s):  
Articular Cartilage ◽  
Core Protein ◽  
Type I ◽  
Human Articular Cartilage ◽  
Aggrecan Core Protein
Sign in / Sign up

Export Citation Format

Share Document