The transforming growth factor-beta 1 was known as having the most important influence on chondrocytes among various growth factors, being abundant in articular chondrocytes and osteocytes. We performed in vitro monolayer cultures of human articular chondrocytes from normal and osteoarthritic patients and studied the transforming growth factor-beta 1 responsiveness of those chondrocytes. The cell-growth curve indicated that the primary osteoarthritic chondrocyte culture with transforming growth factor-beta 1 showed a more rapid growth pattern than normal chondrocytes with or without TGF-beta 1 and osteoarthritic chondrocytes without TGF-beta 1. The osteoarthritic group showed a sharp decline in growth pattern with subsequent culture. The shape of osteoarthritic chondrocytes was bigger and more bizarre compared to those of normal chondrocytes. With subsequent culture, this change became prominent. The transforming growth factor-beta 1 increased the [3H]-TdR uptake in each group. The phenotypes of chondrocytes were more clearly expressed in the normal group. The chondrocytes lost their phenotype (production of collagen type II) following subculture in each group. The transforming growth factor-beta 1 could not inhibit or delay the dedifferentiation process (loss of phenotype).
Cartilage, Articular/drug effects* ; Cartilage, Articular/cytology ; Cell Division/drug effects ; Cells, Cultured ; Human ; Osteoarthritis/pathology ; Reference Values ; Transforming Growth Factor beta/pharmacology*

OBJECTIVETo investigate the effects of different concentrations of Gubishu containing serum on the proliferation of rabbit articular chondrocytes cultured in vitro.

METHODSArticular chondrocytes were obtained from the cartilage of 1-month rabbit and cultured in vitro. They were randomly divided into 8 groups,blank and Gubishu groups in different concentrations (5%, 10%,15%, 20%), MTT assay method was adopted to observe the influence of Gubishu containing serum with different concentrations to the proliferation of chondrocytes after incubated 1, 3, 5, 7 and 9 days.

RESULTSThe proliferation of chondrocytes was dependent on the concentration in Gubishu groups. At same time point,there was significant value between every groups, 20% concentration was greatest (P<0.05); There was significant differences between 5%, 10% and 20% concentration of the blank groups at same time point (P<0.05), and was not between 15% and 20% concentration at the 1, 3, 5 and 7 days (P>0.05), 20% concentration of the blank group was greatest. 20% concentrations of Gubishu containing serum was significantly greater than 20% concentrations of blank group at the 1, 3, 5 and 7 days (P<0.05).

CONCLUSION20% concentrations of Gubishu containing serum can significantly increase the proliferation of chondrocytes, and bring the logarithmic growth period forward to the 3 day.

Animals ; Cartilage, Articular ; cytology ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Chondrocytes ; drug effects ; physiology ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; pharmacology ; Female ; Male ; Rabbits ; Serum

A type of water-soluble carboxymethyl chitosan (O--CMC), with 76% degree of substitution determined by conductivity method, was prepared by using chloroacetic acid to react with C6-OH of chitosan. The solubility of O--CMC was characterized also. Animal experiment in rabbits showed that O--CMC could lubricate arthron, inhibit proliferation of fibroblast cells on rabbits' knee joints, benefit the process of repairing pathologic articular cartilage, and produce good therapeutic effect on rheumatoid arthritis.
Animals ; Arthritis, Experimental ; drug therapy ; pathology ; Cartilage, Articular ; drug effects ; Cell Proliferation ; drug effects ; Chitosan ; administration & dosage ; analogs & derivatives ; therapeutic use ; Female ; Fibroblasts ; drug effects ; Injections, Intra-Articular ; Knee Joint ; drug effects ; Male ; Rabbits

There is evidence from other studies that some degree of cartilage healing may take place after the initiation of an inflammatory response. It is postulated that the induction of the platelet-cartilage interaction may eventuate in cartilage repair. The treatment of fresh articular cartilage with proteolytic enzymes rendered the tissue active as a platelet aggregant. During platelet aggregation a host of active substances are released which are known to play a role in the inflammatory response (Thompson 1975). This study was undertaken to evaluate the effects of trypsin on the surface injury of rabbit hyaline cartilage. The results were as follows: 1) Hyaline cell regeneration was observed only in the group treated with trypsin and blood; 2) Hyaline cartilage regeneration did not occur in the group treated with a single injection of trypsin or blood; 3) There was no significant damage to the healthy articular cartilage by the single injection of trypsin or blood, or both; and 4) Platelets do not adhere to cartilage and superficial damaged cartilage does not induce platelet aggregation.
Animal ; Cartilage, Articular/*drug effects/physiology/ultrastructure ; Cell Division ; Mitosis/physiology ; Platelet Aggregation/drug effects ; Rabbits ; Regeneration ; Trypsin/*pharmacology ; Wound Healing/drug effects/physiology

OBJECTIVETo explore Poloxamer 188, a non-ionic surfactant as a potential tool for early intervention into the chondrocyte damaged by blunt mechanical trauma in vitro.

METHODSThree groups were control group (n = 6), no treatment group (n = 12) and Poloxamer 188 treatment group (n = 12). Two groups are then loaded to 20 MPa in unconfined compression. At 1 and 24 h the percentages of live and dead cells of superficial zone in compressed and control groups were determined with a cell viability stain.

RESULTSAt 1 h post-trauma, specimens of Poloxamer 188 treatment group (76%) had a significantly increased percentage of live cells in the superficial zone versus the no treatment group (55%). In 24 h the percentages of live cells in the superficial zone of the Poloxamer 188 treatment group (57%) were significantly greater than in the no treatment group (38%).

CONCLUSIONSPoloxamer 188 surfactant could help restore the integrity of cell membranes in cartilage damaged by blunt mechanical trauma. Models of mechanical cartilage injury in vitro may explain aspect of the interactions between mechanical forces and degradative pathways which lead to osteoarthritis progression.

Apoptosis ; drug effects ; Cartilage, Articular ; pathology ; Cell Survival ; drug effects ; Chondrocytes ; drug effects ; pathology ; Humans ; In Vitro Techniques ; Poloxamer ; pharmacology ; Random Allocation ; Weight-Bearing

OBJECTIVETo study the effect of growth hormone (GH) on the proliferation and type II collagen secretion of chondrocytes of mandibular condyle in rabbit in vitro.

METHODSFlow cytometry (FCM) and immunohistochemical technique were employed to observe the possible changes.

RESULTS(1) The exogenic GH can enhance the proliferation and synthesis of DNA of the chondrocytes of mandibular condyle in rabbit in vitro. The suitable concentration of GH is 10 microg/ml. The synthesis of DNA reaches the highest level after 12 hours, while the proliferation index (PI) hits the highest after 24 hours. (2) GH (10 microg/ml) can stimulate the secretion of type II collagen of the chondrocytes.

CONCLUSIONThe exogenic GH can enhance the proliferation, the synthesis of DNA and the secretion of type II collagen of the chondrocytes of mandibular condyle in rabbit in vitro.

Animals ; Cartilage, Articular ; cytology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Chondrocytes ; drug effects ; secretion ; Collagen Type II ; drug effects ; Growth Hormone ; pharmacology ; Mandibular Condyle ; cytology ; Rabbits

OBJECTIVETo study the effects of Bushen Zhuangjin Decoction (BZD) containing serum on the apoptosis of chondrocytes induced by mechanics stimulus.

METHODSThe BZD containing serum was extracted. The chondrocyte nutritive media was divided into 3 groups, i.e., the common nutritive medium group, the blank rabbit serum medium group, and the BZD nutritive medium group. The apoptosis of chondrocytes was induced by continuing mechanics stimulus in 24 h. Then the chondrocytes were collected. The apoptosis rate of chondrocytes was determined by flow cytometry. The contents of interleukin 1beta (IL-1beta) and nitric oxide (NO) in the corresponding media were determined.

RESULTSThe apoptosis of chondrocytes in the BZD nutritive medium group (19.55 +/- 7.98)% was lower than that of the common nutritive medium group (39.32 +/- 13.45)% and the blank rabbit serum medium group (37.87 +/- 9.67)%, showing statistical difference (P < 0.05). The contents of IL-1beta and NO were also lower in the BZD nutritive medium group with statistical difference when compared with those of the other two groups (P < 0.05).

CONCLUSIONBZD containing serum could protect mechanics stimulus induced apoptosis of chondrocytes.

Animals ; Apoptosis ; drug effects ; Cartilage, Articular ; drug effects ; Cells, Cultured ; Chondrocytes ; cytology ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Flow Cytometry ; Interleukin-1beta ; analysis ; Nitric Oxide ; analysis ; Rabbits ; Serum

OBJECTIVETo investigate the effects in vitro of 17 beta-estradiol (E2) on the proliferation and metabolism of rabbit mandibular condylar cartilage cells.

METHODSChondrocytes were derived from neonatal rabbit mandibular condylar cartilage using a modified enzyme method. 17 beta-estradiol was added to the culture medium in a variety of concentrations. Cell growth and DNA, collagen, and proteoglycan synthesis were used as indicators of proliferation and differentiation of condylar chondrocytes. These were measured by cell number, 3H-proline and 35S-incorporation, respectively.

RESULTSE2 increased cell number and 3H-thymidine incorporation at 10(-8) to 10(-10) mol/L, and 10(-8) to 10(-11) mol/L in a dose-dependent manner, peaking at 10(-8) mol/L and 10(-9) mol/L, respectively. However, further increase in the concentration of estradiol caused inhibition of both cell number and 3H-thymidine incorporation, and this was significant at 10(-6) mol/L. The effect of E2 on proteoglycan synthesis was similar; the maximum stimulating effect was at 10(-8) mol/L, and inhibition was significant at 10(-6) mol/L. There was no obvious stimulatory effect of E2 on 3H-thymidine incorporation observed.

CONCLUSIONSEstradiol affects condylar chondrocyte cell growth, DNA, and proteoglycan synthesis in a biphasic manner depending on its concentration. This indicates that estrogen may be important in the proliferation and differentiation of mandibular condylar chondrocytes, and could be relevant to some aspects of certain temporomandibular joint diseases by modulating the function of the chondrocytes.

Animals ; Cartilage, Articular ; cytology ; metabolism ; Cell Differentiation ; Cell Division ; drug effects ; Cells, Cultured ; Estradiol ; pharmacology ; Mandibular Condyle ; cytology ; metabolism ; Rabbits

The mechanical properties of natural and synthetic extracellular matrices affect cellular processes and regulate tissue formation. In order to explore the optimal environment for chondrocytes growth in vitro, we investigated the relationship between the mechanical properties of the alginate beads and the ability of chondrocyte proliferation in this study. We measured the compressive properties of alginate with different concentrations by INSTRON 3365,and found that compressive moduli significantly increased with increasing alginate concentration. The rabbit chondrocytes were encapsulated in 1%, 2% and 3% (w/v) alginate beads at high (1 x 10(7)/ml) density. After 4 week's culturing, all the three groups resulted in the limited proliferation of the chondrocytes and the formation of cell clusters resembling cartilaginous tissues. Chondrocytes proliferation was more rapid on lower concentrate gels (1%, 2%) than on the higher concentrate gels (3%). These results suggested that the mechanical properties of scaffold architecture had certain effect on chondrocytes proliferation.
Alginates ; pharmacology ; Animals ; Cartilage, Articular ; cytology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Chondrocytes ; cytology ; Compressive Strength ; drug effects ; Glucuronic Acid ; pharmacology ; Hexuronic Acids ; pharmacology ; Hydrogels ; pharmacology ; Rabbits

OBJECTIVETo observe the effect of isolating the chondrocytes from articular cartilage with the method of three-step enzymatic digestion, and the biological characteristics of the isolated chondrocytes during cultivation in vitro in order to evaluate their biological activity.

METHODSThe method of three-step enzymatic digestion was designed that the articular cartilage was digested one by one with the 1 g/L trypsin and 1 g/L EDTA, 1 g/L hyaluronidase and 2 g/L collagenase I in the culture medium to isolate chondrocytes. The harvesting and viability rate of the primary chondrocytes were detected. During the passage cultivation in vitro, the changes of the chondrocytes shape and growth were observed, the changes of the collagen type I and II and aggrecan in the extracellular matrix were investigated and detected.

RESULTS(1) The extracellular matrix of articular cartilage was completely dissolved by the three-step enzymatic digestion, and the chondrocytes were completely isolated from the solid matrix. The number of the harvested chondrocytes from every gram of wet cartilage was 50.3 x 10(6) on average, and their viability rate was 98.8% on average. (2) The primary and first passage chondrocytes had triangle or multi-angle shape, and became elliptic shape at the growing confluence with the positive immunohistochemical stain of collagen type II and the strong heterochromia to toluidine blue. The content of sulfate glycosaminoglycans (GAG) in the extracellular matrix of the primary passage cells was (92 +/- 10) microg/cm(2). The chondrocytes after the third passaging gradually became spindle shape with the negative stain of collagen type II and the weak heterochromia to toluidine blue. The content of sulfate GAG of the fourth passage cells was (48 +/- 12) microg/cm(2).

CONCLUSION(1) The method of three-step enzymatic digestion can make the extracellular matrix of articular cartilage completely degraded, and has advantages in the high efficiency of harvesting primary chondrocytes, high cellular viability rate and simple manipulation. (2) The primary and first passage chondrocytes have fine biological activity, and the chondrocytes after the third passaging have lost their special biological activity.

Animals ; Cartilage, Articular ; cytology ; drug effects ; Cell Culture Techniques ; Cell Separation ; methods ; Cells, Cultured ; Chondrocytes ; cytology ; Collagenases ; pharmacology ; Female ; Hyaluronoglucosaminidase ; pharmacology ; Male ; Rabbits ; Trypsin ; pharmacology