The uptake in vitro of sulfur-35 by costal cartilage obtained from nine rabbits 11 days after an intravenous injection of crude papain solution was compared with that in costal cartilage from eight normal untreated rabbits. An increased fixation of the isotope was found in treated animals compared with controls. The depletion of cartilage matrix by papain provided an experimental situation to t...

Human articular chondrocytes are expanded in monolayer culture in order to obtain sufficient cells for matrix-associated cartilage transplantation. During this proliferation process, the cells change their shape as well as their expression profile. These changes resemble those that occur during embryogenesis, when the limb anlagen form the interzone that later develops the joint cleft. We analy...

Endochondral ossification begins from the condensation and differentiation of mesenchymal cells into cartilage. The cartilage then goes through a program of cell proliferation, hypertrophic differentiation, calcification, apoptosis, and eventually is replaced by bone. Unlike most cartilage, articular cartilage is arrested before terminal hypertrophic differentiation. In this study, we showed th...

Osteoarthritis is characterised by progressive loss of articular cartilage through the increase of catabolic metalloproteinases, and chondrocyte cytoskeleton disruption has also been reported. In this regard, we studied the effect of Heterotheca inuloides essential oil (HIEO) on the distribution and immunolocalisation of actin, vimentin and tubulin of chondrocytes from cultured rat articular ca...

Altered chondrocyte differentiation, including development of chondrocyte hypertrophy, mediates osteoarthritis and pathologic articular cartilage matrix calcification. Similar changes in endochondral chondrocyte differentiation are essential for physiologic growth plate mineralization. In both articular and growth plate cartilages, chondrocyte hypertrophy is associated with up-regulated express...

INTRODUCTION 15-Lipoxygenases and their metabolites have been shown to exhibit anti-inflammatory and immunomodulatory properties, but little is known regarding their expression and function in chondrocytes. The objective of this study was to evaluate the expression of 15-lipoxygenase-1 and -2 in human articular chondrocytes, and to investigate the effects of their metabolites 13(S)-hydroxy octa...

BACKGROUND While articular chondrocytes are among those appropriate candidates for cartilage regeneration, the cell dedifferentiation during monolayer culture has limited their application. Several investigations have indicated the usefulness of alginate, but the topic of proliferation and differentiation of chondrocytes in alginate culture has still remained controversial. METHODS Rat articu...

Chondrocytes are the resident cells of cartilage, which synthesize and maintain the extracellular matrix. The range of known potassium channels expressed by these unique cells is continually increasing. Since chondrocytes are non-excitable, and do not need to be repolarized following action potentials, the function of potassium channels in these cells has, until recently, remained completely un...

Prostaglandin E synthase (PGES) including isoenzymes of membrane-associated PGES (mPGES)-1, mPGES-2, and cytosolic PGES (cPGES) is the recently identified terminal enzyme of the arachidonic acid cascade. PGES converts prostaglandin (PG)H2 to PGE2 downstream of cyclooxygenase (COX). We investigated the expression of PGES isoenzyme in articular chondrocytes from patients with osteoarthritis (OA)....

INTRODUCTION Articular cartilage is organized into several zones with differing properties, which as a whole contribute to the overall function of the tissue. These distinct properties arise from zonal differences in chondrocyte phenotype, as previously described [1,2]. To date, however, no studies have addressed zonal variations among single chondrocytes. The goal of this study was to quantify...