OBJECTIVETo establish an immortalized marrow mesenchymal stem cell line to facilitate advances in cartilage engineering research.

METHODSHuman telomerase reverse transcriptase (hTERT) cDNA was transferred into primary human marrow mesenchymal stem cells (hMSC) by retroviral vector pLEGFP-C1-hTERT. Subsequently G418 resistant cell clone was screened and expanded for further studies. hMSC biomarkers and hTERT expression were confirmed by examination. Transfected hMSC was induced to differentiate into chondrocyte using TGF-P1 and dexamethasone.

RESULTSUp-regulated hTERT expression was detected in transfected hMSC. hMSC-hTERT cells could be induced to differentiate into chondrocyte. Higher telomerase activity in transfected cells was maintained for 50 population doublings so far. Collagen II could be detected in induced transfected hMSC by immunocytochemical and hybridization in situ.

CONCLUSIONSEctopic expression of hTERT can effectively immortalize hMSC in vitro. Immortalized hMSC can be induced to differentiate into chondrocyte under certain condition. It may be an ideal target of further studies in cartilage engineering.

Bone Marrow Cells ; cytology ; drug effects ; metabolism ; Cell Differentiation ; drug effects ; Cell Line, Transformed ; Chondrocytes ; cytology ; Humans ; Mesenchymal Stromal Cells ; cytology ; drug effects ; metabolism ; Telomerase ; genetics ; metabolism ; Transfection

Vertically aligned, laterally spaced nanoscale titanium nanotubes were grown on a titanium surface by anodization, and the growth of chondroprogenitors on the resulting surfaces was investigated. Surfaces bearing nanotubes of 70 to 100 nm in diameter were found to trigger the morphological transition to a cortical actin pattern and rounded cell shape (both indicative of chondrocytic differentiation), as well as the up-regulation of type II collagen and integrin beta4 protein expression through the down-regulation of Erk activity. Inhibition of Erk signaling reduced stress fiber formation and induced the transition to the cortical actin pattern in cells cultured on 30-nm-diameter nanotubes, which maintained their fibroblastoid morphologies in the absence of Erk inhibition. Collectively, these results indicate that a titanium-based nanotube surface can support chondrocytic functions among chondroprogenitors, and may therefore be useful for future cartilaginous applications.
Animals ; Apoptosis ; Cell Differentiation/*drug effects ; Cells, Cultured ; Chick Embryo ; Chickens ; Chondrocytes/cytology/drug effects/metabolism ; Chondrogenesis/*drug effects ; Collagen Type II/metabolism ; Immunohistochemistry ; Integrin beta4/metabolism ; Mesenchymal Stem Cells/*cytology/*drug effects/metabolism ; Nanotubes/*chemistry ; Titanium/*chemistry/*pharmacology

OBJECTIVETo observe the effect of single herb pilose antler (PA) on the expression of Smad2 and Smad3 in the cartilage of osteoarthritis (OA) rats.

METHODSOne hundred 3-month old female healthy SD rats, (200 +/- 20) g, were recruited and routinely fed for 1 week. They were randomly divided into 5 groups, i.e., the low dose PA group, the high dose PA group, the normal saline control group, the model group, and the normal control group, 20 in each group. The model was prepared using classic Hulth method except the normal control group. After 6-week modeling, the model was confirmed successful by pathologic observation. PA at 0.021 g/100 g and 0.084 g/1 00 g was given by gastrogavage to rats in the low dose PA group and the high dose PA group respectively. Normal saline was administered to those in the normal saline control group. No treatment was given to rats in the normal control group and the model group. Bilateral knee cartilages were harvested at week 2,4, and 6. mRNA and protein expressions of Smad2 and Smad3 were detected by immunohistochemical assay, fluorescent quantitative PCR, and Western blot.

RESULTSOA model was successfully prepared by pathological observation. Results of immunohistochemical assay showed that Smad2 and Smad3 expressed extensively in the cartilage, and located inside the chondrocyte membrane. Compared with the model group, mRNA expression of Smad2 and Smad3 obviously increased in the low dose PA group and the high dose PA group at week 2, 4, and 6, showing statistical difference (P < 0.05). Compared with the same group at week 4 after gastrogavage, mRNA expression of Smad2 and Smad3 obviously decreased in the low dose PA group and the high dose PA group at week 6, showing statistical difference (P < 0.05). Compared with the model group, protein expression of Smad2 and Smad3 obviously increased in the chondrocytes of the low dose PA group and the high dose PA group at week 2 and 4, showing statistical difference (P < 0.01). Compared with the same group at week 2 after gastrogavage, protein expression of Smad2 and Smad3 obviously increased in the low dose PA group and the high dose PA group at week 4, showing statistical difference (P < 0.01). Compared with the same group at week 4 after gastrogavage, protein expression of Smad2 and Smad3 obviously decreased in the low dose PA group and the high dose PA group at week 6, showing statistical difference (P < 0.01).

CONCLUSIONS(1) The pilose antler could repair cartilages by regulating mRNA and protein expressions of Smad2 and Smad3. (2) Up-regulating mRNA and protein expressions of Smad2 and Smad3 might be one of important mechanisms for the pathogenesis of OA.

Animals ; Antlers ; chemistry ; Cartilage ; cytology ; metabolism ; Chondrocytes ; drug effects ; metabolism ; Female ; Medicine, Chinese Traditional ; Osteoarthritis ; drug therapy ; metabolism ; Rats ; Rats, Sprague-Dawley ; Smad2 Protein ; metabolism ; Smad3 Protein ; metabolism

Due to the poor repair ability of cartilage tissue, regenerative medicine still faces great challenges in the repair of large articular cartilage defects. Quercetin is widely applied as a traditional Chinese medicine in tissue regeneration including liver, bone and skin tissues. However, the evidence for its effects and internal mechanisms for cartilage regeneration are limited. In the present study, the effects of quercetin on chondrocyte function were systematically evaluated by CCK8 assay, PCR assay, cartilaginous matrix staining assays, immunofluorescence assay, and western blotting. The results showed that quercetin significantly up-regulated the expression of chondrogenesis genes and stimulated the secretion of GAG (glycosaminoglycan) through activating the ERK, P38 and AKT signalling pathways in a dose-dependent manner. Furthermore, in vivo experiments revealed that quercetin-loaded silk protein scaffolds dramatically stimulated the formation of new cartilage-like tissue with higher histological scores in rat femoral cartilage defects. These data suggest that quercetin can effectively stimulate chondrogenesis in vitro and in vivo, demonstrating the potential application of quercetin in the regeneration of cartilage defects.
Animals ; Cartilage/cytology* ; Chondrocytes/drug effects* ; Chondrogenesis/drug effects* ; Extracellular Matrix/metabolism* ; Quercetin/pharmacology* ; Rats ; Signal Transduction/drug effects* ; Tissue Scaffolds

OBJECTIVETo study the effects of zuogui pill (ZP) contained serum on the gene expressions of type-II collagen and proteoglycan during the differentiation of mesenchymal stem cells (MSCs) towards chondrocytes.

METHODSMSCs isolated from rat bone marrow were in vitro induced differentiation towards chondrocytes and stimulated with high- (57 g/kg), middle- (28.5 g/kg), and low-dose (9.5 g/kg) ZP contained serums and serum of blank rats. The proliferation of MSCs was analyzed by CCK-8 method. The 3rd-passage MSCs were divided into the blank control group (by adding serum of the blank group rats), the induction control group (by adding the induction fluid and serum of the blank group rats), and the ZP contained serum group (by adding the induction fluid and middle-dose ZP contained serum). The expressions of type-II collagen and proteoglycan were determined using reverse transcriptase PCR, Real-time PCR, and immunohistochemistry.

RESULTSCompared with the blank control group, the proliferation of MSCs could be promoted by ZP contained serum at different doses (P < 0.05), with the most obvious effect shown in the middle-dose ZP contained serum group (P < 0.05). The mRNA and protein expressions of type-II collagen could be identified in the induction control group and the ZP contained serum group on the 21st day of the induction. Of them, the mRNA expression of type-II collagen in ZP contained serum groups was obviously higher than that of the induction control group. Results of Real-time PCR showed that on the 21st day of the induction, the mRNA expression quantitation of proteoglycan in ZP contained serum groups was about 16-fold and 3-fold of the levels on the 7th day and the 14th day (P < 0.05), obviously higher than those of the induction control group (P < 0.05).

CONCLUSIONZP contained serum could induce MSCs proliferation, the gene expressions of type- II collagen and proteoglycan, which might be one of its molecular bases for protecting the cartilage.

Animals ; Cell Differentiation ; drug effects ; Cells, Cultured ; Chondrocytes ; cytology ; drug effects ; metabolism ; Collagen Type II ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Female ; Male ; Mesenchymal Stromal Cells ; cytology ; drug effects ; metabolism ; Proteoglycans ; metabolism ; Rats

OBJECTIVETo evaluate the effect of interleukin-6 (IL-6) on the biological behaviors of the chondrocytes in the cartilage endplate of rabbits.

METHODSChondrocytes isolated from the cartilage endplate of New Zealand rabbits, verified for their biological characteristics by such means as toluidine blue staining for type II collagen, were treated with IL-6 at different concentrations. The proliferation of the chondrocytes was evaluated by MTT assay at different time points following the treatment, the cell cycle changes were determined by flow cytometry and the changes of aggrecan and type II collagen mRNAs detected by RT-PCR.

RESULTSAt the concentrations of 10, 50 and 100 ng/ml, IL-6 did not obviously affect the rate of chondrocyte proliferation. IL-6 at 50 ng/ml resulted in no obvious changes of the cell cycle of the chondrocytes, but significantly decreased the expression of collagen IIa mRNA.

CONCLUSIONIL-6 has no effect on the proliferation and cell cycle of the chondrocytes, but at higher concentrations, it inhibits matrix synthesis of the chondrocytes to promote intervertebral disc degeneration.

Aggrecans ; genetics ; Animals ; Cartilage ; cytology ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Chondrocytes ; cytology ; drug effects ; metabolism ; Collagen Type II ; genetics ; Female ; Gene Expression Regulation ; drug effects ; Interleukin-6 ; pharmacology ; Male ; RNA, Messenger ; genetics ; metabolism ; Rabbits

OBJECTIVE: To explore the effect of insulin-like growth factor (IGF-1) on the concentration of NO and PGE(2) in the supernatant of rabbit articular chondrocytes induced by IL-1, and to explore the mechanism of IGF-1 in the development of osteoarthritis (OA). METHODS: The samples were divided into 7 groups: IL-1beta 10 microg/L group, IL-1beta 10 microg/L+IGF-1 1 microg/L group, IL-1beta 10 microg/L+IGF-1 10 microg/L group, IL-1beta 10 microg/L+IGF-1 50 microg/L group, IL-1beta 10 microg/L+IGF-1 100 microg/L group, IGF-1 50 microg/L group, and a blank control group. The chondrocytes from the articular cartilage of 2 month old rabbits were cultivated and identified, and then co-cultured in the second filial generation chondrocytes on plates with or without recombinant human IGF-1 or IL-1. The concentration of NO was detected by nitrate reductase kit, and that of PGE(2) by enzyme-linked immunosorbent assay (ELISA). The results were analyzed by statistical method. RESULTS: The average value of NO and PGE(2) was (89.971+/-10.224) micromol/L and (22.028+/-8.731) micromol/L in the IL-1beta 10 microg/L group, and (12.404+/-8.809) micromol/L and (1.900+/-0.227) ng/L in the blank control group. The concentration of NO and PGE(2) in IL-1beta 10 microg/L group was significantly higher than that in the blank control group (P<0.05). At the same concentration of 10 microg/L, IGF-1 could dose-dependently decrease the increase of NO and PGE(2) concentration induced by IL-1beta in the chondrocytes supernatant in vitro, and the optimum concentration of IGF-1 was 50 microg/L. CONCLUSION IL-1 can significantly increase the concentration of NO and PGE(2), and IGF-1 can dose-dependently decrease the concentration of NO and PGE(2) in the chondrocytes supernatant in vitro. The optimum concentration of IGF-1 was 50 microg/L.
Animals ; Cartilage, Articular ; cytology ; metabolism ; Cells, Cultured ; Chondrocytes ; drug effects ; metabolism ; Dinoprostone ; metabolism ; Insulin-Like Growth Factor I ; pharmacology ; Interleukin-1 ; pharmacology ; Nitric Oxide ; metabolism ; Osteoarthritis ; metabolism ; Rabbits

OBJECTIVETo investigate the effect of water extracts from Duhuo Jisheng decoction on chondrocyte G1 phase.

METHODSChondrocytes were collected from four-week-old SD rats to establish the chondrocyte in vitro culture system. The third generation of chondrocytes was intervened. MTT method was used to measure the effect of water extracts from different concentrations of Duhuo Jisheng decoction on chondrocyte activity. The expressions of Chondrocyte Cyclin D1, CDK4, CDK6 and P21 mRNA in the blank group and low, middle and high-dose groups (100, 200, 400 mg x L(-1)) were detected by RT-PCR method.

RESULTThe MTT assay showed that the chondrocyte activity significantly increased within specific drug concentrations (50-800 mg x L(-1)) (P < 0.01); After the intervention for 24 h, the expressions of CyclinD1, CDK4 and CDK6 mRNA in all dose groups notably increased (P < 0.05), with the maximum expressions at the concentration of 200 mg x L(-1); The expression of P21 mRNA decreased, particularly at the concentration of 200 mg x L(-1) (P < 0.01).

CONCLUSIONWater extracts from Duhuo Jisheng decoction can promote chondrocyte proliferation by effecting the expression of chondrocyte G1 phase regulator mRNA.

Animals ; Cell Cycle Proteins ; genetics ; metabolism ; Cell Proliferation ; drug effects ; Cells, Cultured ; Chondrocytes ; cytology ; drug effects ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; G1 Phase ; drug effects ; Gene Expression Regulation ; drug effects ; Male ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVEThis study was to explore the cytotoxic effect and the related injury mechanism of deoxynivalenol (DON) on articular chondrocytes in human embryo.

METHODSArticular cartilage cells were isolated from knees of human embryo and cultured in DMEM/F12 medium. The cells of the 4th generation were divided into five groups and incubated with varying concentrations of DON as the followings: control group and group with DON of 0.1, 0.2, 0.4, 1.0 µg/ml. The effects of DON were observed 72 hours after incubation. Cell apoptosis was assayed by flow cytometry (FCM) with Annexin V-FITC/PI staining; MMP-13 and PGE2 were detected by ELISA kits; NO was measured by Griess assay with spectrophotometer. Inducible nitric oxide synthase (iNOS) and collagen II in cells were detected by FCM. The expression levels of iNOS, mRNA and collagen II mRNA were measured with RT-PCR.

RESULTSThe rates of cell apoptosis in DON groups were 6.78% - 19.05%, which were significantly higher than that in control (1.20%, F = 174.761, P < 0.05). The levels of NO in DON groups were 20.8 - 40.7 µmol/L, which were significantly higher than that in control (10.2 µmol/L, F = 91.966, P < 0.05). The levels of MMP-13 in DON groups were 0.25 - 0.56 µmol/L, which were significantly higher than that in control (0 µmol/L, F = 78.420, P < 0.05). The levels of PGE2 in DON groups were 3.2-20.6 µmol/L, which were significantly higher than that in control (11.6 µmol/L, F = 276.453, P < 0.05). The proportions of cells with positive iNOS in DON groups were 14.8% - 56.8% which were significantly higher than that in controls (7.1%, F = 214.614, P < 0.05). The proportions of cells with positive collagen II in groups with DON of 0.4 µg/ml and 1.0 µg/ml were 56.7% and 52.7%, which were significantly lower than that in control (62.2%, F = 5.134, P < 0.05). The relative absorbance values of iNOS mRNA in DON groups were 1.07 - 1.33, which were significantly higher than that in control (0.62, F = 8.358, P < 0.05). The levels of collagen II mRNA in groups with DON of 0.4 µg/ml and 1.0 µg/ml were 0.83 and 0.82, which were significantly lower than that in control (1.14, F = 7.887, P < 0.05).

CONCLUSIONDON could promote anabolism of NO in articular cartilage cells by which up-regulated the expression of PGE2 and MMP-13, which both promoted resolution of articular cartilage matrix such as collagen II. DON induced apoptosis in articular cartilage cells.

Cartilage, Articular ; cytology ; embryology ; Cells, Cultured ; Chondrocytes ; drug effects ; metabolism ; Dinoprostone ; metabolism ; Humans ; Matrix Metalloproteinase 13 ; metabolism ; Nitric Oxide ; biosynthesis ; Trichothecenes ; toxicity

OBJECTIVETo investigate regulation function of anodonta glucan HBP-A on chondrocytes through Wnt pathway in vitro.

METHODSRat chondrocytes were cultured and differentiated induced with IL-1beta (10 ng/ml) in vitro. Chondrocytes were divided into five groups:IL-13 group,IL-1beta + IWP-2 (5 microM,Wnt pathway inhibitor) group, IL-1beta + HBP-A (0.3 mg/ml) group and IL-1beta + IWP-2 + HBP-A group. Wnt-3a, beta-catenin (24 h,48 h,72 h) and MMP-13(72 h) genes expression were detected by Rt-PCR, while beta-catenin, MMP-13, Sox-9 and coll-II (48 h) protein expression were measured by Western-blot.

RESULTSAfter induction of IL-1beta, gene expression of Wnt-3a, beta-catenin and MMP-13 were increased,so were the protein expression of beta-catenin and MMP-13. In contrast,protein expression of Sox-9 and Coll-II were declined. Following addition of HBP-A, Wnt-3a, beta-catenin and MMP-13 were shown as induction of IL-1beta, but protein expression of Sox-9 and Coll-II were upgraded. Combining HBP-A with IWP-2 led to the lowest level in Wnt-3a, beta-catenin gene and beta-catenin protein expression and highest expression of Sox-9 protein.

CONCLUSIONHBP-A could not only delay the differentiation of chondrocytes through downgrading the signal expression of Wnt/beta-catenin,but also adjust the expression of Wnt-3a, beta-catenin and Sox-9 when combinated with the Wnt inhibitor.

Animals ; Anodonta ; chemistry ; Cell Differentiation ; drug effects ; Cells, Cultured ; Chondrocytes ; cytology ; drug effects ; metabolism ; Glucans ; pharmacology ; Interleukin-1beta ; metabolism ; Rats ; Wnt Signaling Pathway ; drug effects ; Wnt3A Protein ; genetics ; metabolism ; beta Catenin ; metabolism