1.Effect of five species of Epimedium on growth of cartilage and proliferation of cartilage cell in vitro.
Kun FENG ; Wen XIE ; Bao-Long CHEN ; Jian-Zhi WANG ; Jian-Gang GUO
China Journal of Chinese Materia Medica 2006;31(24):2065-2067
OBJECTIVETo observe the effect of Epimedium brevicornum, E. sagittatum, E. koreanum, E, wushanense and E. elongntum on the growth of cartilage and proliferation of cartilage cell in vitro.
METHODAccording to the paired design method, either femur of each chichen embryo was put into the control tube with the medium containing no Epimedium injection, and the other was put into the treated tube with the medium containing 3% Epimedium injection. The length and weight of cultured cartilage and proliferation of cartilage cell (MTY method) were used as the indices to observe the cartilage biological activities of the five species of Epimedium in culture.
RESULTThe results showed that the indices of length, weight and MTT in the E. brevicornum and E. sagittatum group were significantly higher than those in the contral group, but the above indices in groups E. koreanum, E. wushanens and E. elongntum were similar to those of the control with no statistical difference.
CONCLUSIONE. brevicornum and E. sagittatum can improve the growth of cartilage and proliferation of cartilage cell in vitro, and other three Epimedium have not the same effect in this test.
Animals ; Cartilage ; cytology ; drug effects ; embryology ; Cell Proliferation ; drug effects ; Chick Embryo ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Epimedium ; chemistry ; classification ; Plants, Medicinal ; chemistry ; classification ; Species Specificity
2.Regulation of single herb pilose antler on the expression of Smad2 and Smad3 in the cartilage of OA rats: an experimental research.
Wei NIU ; Zhi-Tao SUN ; Xue-Wei CAO ; Mu-Xun WANG ; Zheng YAN ; Da GUO ; Yue-Guang FANG
Chinese Journal of Integrated Traditional and Western Medicine 2014;34(2):209-213
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
3.Protective effect of diosgenin on chondrocytes mediated by JAK2/STAT3 signaling pathway in mice with osteoarthritis.
Jun LIU ; Xiaole HE ; Ping ZHEN ; Shenghu ZHOU ; Xusheng LI
Journal of Zhejiang University. Medical sciences 2016;45(5):453-460
To investigate the effect of diosgenin (Dgn) on chondrocytes and its relation to JAK2/STAT3 signaling pathway in mice with osteoarthritis (OA).Fifteen male C57BL/6 mice were randomly divided into three groups:control group, OA group and OA+Dgn group. After 4 weeks of treatment, the histopathological changes of cartilage tissue were observed by toluidine blue staining under light microscopy and the ultrastructure of chondrocytes was observed under electron microscopy. The primarily cultured chondrocytes of OA mice were randomly divided into 4 groups:(1) OA group, (2) Dgn group, (3) Dgn+AG490 group, (4) AG490 group. The expression of p-JAK2, p-STAT3, Bax, succinate dehydrogenase (SDH) and cytochrome c oxidase (COX) were detected by Western blotting, and superoxide dismutase (SOD) was detected using colorimetric method.The morphological observation showed that the chondrocytes of OA group presented considerable pathological changes, while the chondrocytes in OA+Dgn group maintained intact membrane. Electron microscopy observation found obvious injury in cartilage tissues of OA group, while that in OA+Dgn group remained smooth. Compared with OA group, the expressions of p-JAK2 and p-STAT3 in chondrocytes of Dgn group were increased (all<0.05), and the expressions of Bax protein, SDH, COX and SOD were decreased (all<0.05). While compared with Dgn group, the expressions of p-JAK2, p-STAT3, SDH, COX and SOD in chondrocytes of Dgn+AG490 group were decreased (all<0.05), and the expression of Bax protein was increased (<0.05).Diosgenin can inhibit apoptosis and increase mitochondrial oxidative stress capacity of chondrocytes in mice with osteoarthritis, which is closely related to the activation of JAK2/STAT3 signaling pathway.
Animals
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Apoptosis
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drug effects
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Cartilage
;
drug effects
;
pathology
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Chondrocytes
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chemistry
;
drug effects
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pathology
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Diosgenin
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pharmacology
;
Electron Transport Complex IV
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metabolism
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Janus Kinase 2
;
drug effects
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Male
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Mice
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Mice, Inbred C57BL
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Mitochondria
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drug effects
;
genetics
;
Osteoarthritis
;
genetics
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physiopathology
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Oxidative Stress
;
drug effects
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STAT3 Transcription Factor
;
drug effects
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Signal Transduction
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Succinate Dehydrogenase
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metabolism
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Superoxide Dismutase
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metabolism
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Tyrphostins
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pharmacology
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bcl-2-Associated X Protein
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metabolism
4.Studies of poly(vinyl alcohol)/hydroxylapatite hydrogels compounds for cartilage implantation.
Yudong ZHENG ; Yingjun WANG ; Xiaofen CHEN ; Qing LIU ; Yi LU
Journal of Biomedical Engineering 2003;20(3):401-465
The structures and properties of polyvinyl alcohol (PVA)/hydroxylapatite(HA) composites were investigated. The components and processing conditions were studied for preparation of optimum compound hydrogels with good lubricating feature and high bioactivity. The properties, such as stretch strength, compress strength, friction, compress stress relaxation of various compound hydrogels were compared. The micro-morphology of PVA hydrogels and PVA/HA hydrogels were investigated by use of SEM. It was found that the addition of HA could improve the lubricating feature and mechanical strength of hydrogels, and its compress stress relaxation properties were closer to those of natural cartilages.
Biocompatible Materials
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chemical synthesis
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chemistry
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pharmacology
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Biomechanical Phenomena
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Cartilage, Articular
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drug effects
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transplantation
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Durapatite
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chemical synthesis
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chemistry
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pharmacology
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Joint Prosthesis
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Materials Testing
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Polyvinyl Alcohol
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chemical synthesis
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chemistry
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pharmacology
;
Transplantation
5.Methanol extract of Celastrus orbiculatu suppresses synovial hyperplasia and cartilage erosion and degradation in rheumatoid arthritis.
Chang-hong XIAO ; Wei-wang GU ; Jia-ning ZHANG ; Guo-qiang CHEN ; Shi-feng HUANG ; Min YANG ; De-chao CHEN ; Jie CHEN ; Dan XIAO
Journal of Southern Medical University 2007;27(7):945-950
OBJECTIVETo investigate the effects of methanol extract of Celastrus orbiculatu (MECO) on synovial hyperplasia and cartilage erosion and degradation in rheumatoid arthritis (RA), and explore the possible mechanisms to provide clues for new drug development for RA treatment.
METHODSThe articular synovium from patients with RA and normal articular cartilage were co-implanted into the back of severe combined immunodeficient (SCID)mice to establish the chimeric model SCID- HuRAg. Four weeks later, the mice were given MECO intragastrically at 30 mg/day, leflunomide at 500 microg/day or distilled water, respectively, for 4 consecutive weeks. After completion of the treatments, the histological scores of the grafts for synovial hyperplasia, cartilage invasion by synoviocyte and cartilage degradation around the chondrocytes were evaluated, and serum level of tumor necrosis factor-alpha (TNF-alpha) was measured with radioimmunoassay. The expression of TNF-alpha mRNA and the cell apoptosis in the synovium were detected with in situ hybridization (ISH) and TUNEL, respectively, and the results were analyzed with the image analysis system.
RESULTSThe grafts survived in the mice till the end of experiment. MECO and leflunomide, in comparison with distilled water, significantly lowered the scores for synovial hyperlasia (2.00+/-0.76 and 2.25+/-0.89 vs 3.63+/-0.52), cartilage erosion (1.69+/-0.80 and 2.00+/-1.36 vs 3.75+/-0.53), cartilage degradation (1.88+/-0.83 and 2.13+/-0.83 vs 3.63+/-0.74) and serum TNF-alpha level (0.84+/-0.09 and 0.83+/-0.12 vs 0.99+/-0.11 ng/ml). Cell apoptosis of the synovium increased significantly with MECO and leflunomide treatments, but the expression of TNF-alpha mRNA in the synovium decreased significantly in MECO group.
CONCLUSIONMECO can effectively suppress synovial hyperplasia and cartilage erosion and degradation SCID-HuRAg mice by reducing TNF-alpha production in the synovium and promoting synovial apoptosis. MECO can be comparable with leflunomide in their effect, but the former is more effective in suppressing TNF-alpha expression in the synovium.
Animals ; Apoptosis ; drug effects ; Arthritis, Rheumatoid ; complications ; drug therapy ; metabolism ; pathology ; Cartilage Diseases ; complications ; drug therapy ; metabolism ; pathology ; Celastrus ; chemistry ; Cell Transplantation ; Female ; Gene Expression Regulation ; drug effects ; Humans ; Hyperplasia ; complications ; drug therapy ; Male ; Methanol ; chemistry ; Mice ; Plant Extracts ; isolation & purification ; pharmacology ; therapeutic use ; RNA, Messenger ; genetics ; metabolism ; Synovial Membrane ; drug effects ; pathology ; transplantation ; Tumor Necrosis Factor-alpha ; blood ; genetics
6.Experimental study of velvet antler polypeptides against oxidative damage of osteoarthritis cartilage cells.
Zhen-hua LI ; Wen-hai ZHAO ; Qiu-li ZHOU
China Journal of Orthopaedics and Traumatology 2011;24(3):245-248
OBJECTIVETo study reverse effect of the oxidative damage on cartilage cells of velvet antler polypeptides (VAPS), and to investigate the main mechanism of VAPS to protect cartilage cells through antioxidant.
METHODSFifteen Japanese white rabbits of 5-month-old were selected in this study. Animal model was established by method of Hulth osteoarthritis animal model. The anterior and posterior cruciate ligament and medial collateral ligament were cut off and medial meniscus were cut, articular cartilage cell cultured in vitro. Cells in the sham operation group was the normal control group, osteoarthritis cartilage cells in the model groups were added VAPS 6.25, 12.5, 25 microg/ml respectively. A group of animals were sacrificed every week form the ninth weeks(two months) and the cartilage cells were isolated and cultured. For 8 weeks,the reactive oxygen species level in chondrocytes were detected by DCFH-DA, the content of NO, SOD and GSH-Px in cell culture supernatant were detected by Griess method.
RESULTSDCFH-DA detection of intracellular reactive oxygen species was (5.46 +/- 0.46)in the control group, (12.08 +/- 0.74) in the model groups. The model group compared with the control group by t test with the P value less than < 0.001. DCFH-DA detection of intracellular reactive oxygen species was (9.81 +/- 0.59)in VAPS 6.25 microg/ ml group, (7.83 +/- 0.63) in the VAPS 12.5 microg/ml group, (6.89 +/- 0.71) in the VAPS 25 microg/ml group, as compared with model group there were statistically significant difference (P < 0.05). The content of NaNO2, SOD and GSH-Px in osteoarthritis model group was (5.60 +/- 0.45) microM, (38.56 +/- 12.53) U/ml and (151.90 +/- 25.60) U, as compared with control group there were statistically significant difference (P < 0.001, P < 0.05); The content of NaNO2 was (4.34 +/- 0.39), M in VAPS 6.25 microg/ml group, (3.67 +/- 0.36) microM in the VAPS 12.5 microg/ml group, (3.20 +/- 0.27) microM in the VAPS 25 microg/ml group, as compared with model group there were statistically significant difference (P < 0.01). The content of SOD was (49.91 +/- 5.77) U/ml in VAPS 6.25 microg/ml group, (54.05 +/- 5.27) U/ml in the VAPS 12.5 microg/ml group, (57.44 +/- 5.70) U/ml in the VAPS 25 microg/mL group, as compared with model group there was statistically significant (P < 0.05). The content of GSH-Px was (172.50 +/- 18.65) U in VAPS 6.25 microg/ml group, (202.10 +/- 21.60) U in the VAPS 12.5 microg/ml group, (315.80 +/- 10.50) U in the VAPS 25 microg/ml group, the VAPS 12.5 microg/mL group and VAPS 25 microg/ml group was compared with model group, there were statistically significant difference (P < 0.01).
CONCLUSIONThe VAPS have antioxidative damage effect of osteoarthritis cartilage cells within a certain range and dose-dependent manner. It may be the main mechanism for velvet antler polypeptides to treat osteoarthritis.
Animals ; Antlers ; chemistry ; Cartilage ; drug effects ; metabolism ; pathology ; Female ; Glutathione ; blood ; Male ; Nitric Oxide ; blood ; Osteoarthritis ; blood ; metabolism ; pathology ; Oxidative Stress ; drug effects ; Peptides ; pharmacology ; Rabbits ; Reactive Oxygen Species ; metabolism ; Superoxide Dismutase ; blood
7.Effect of Combined Sex Hormone Replacement on Bone/Cartilage Turnover in a Murine Model of Osteoarthritis.
Jae Hyuk YANG ; Ji Hun KIM ; Deuk Soo LIM ; Kwang Jun OH
Clinics in Orthopedic Surgery 2012;4(3):234-241
BACKGROUND: Estrogens act on estrogen receptors distributed in articular cartilages, synovial membrane, and ligaments, which are thought to be related with degenerative changes. Meanwhile, progesterone is known to have a weak anabolic action on bone formation This study evaluates the effects of estrogen and progesterone hormone on bone/cartilage turnover in ovariectomized (OVX) rats. METHODS: Thirty-five 7-month-old female Sprague-Dawley rats were randomly divided into 5 groups and then ovariectomized bilaterally except the sham control group. The first and the second group acting as controls did not receive hormonal therapy, the third group received estrogen, the fourth group received progesterone, and the fifth group received combination of both hormones 10 weeks after surgery. Evaluations were done using the serum levels of cartilage oligomeric matrix protein (COMP) for cartilage turnover, collagen type I C-telopeptide (CTX-1) and osteocalcin (OC) for bone turnover at 11, 15, 19 weeks after OVX and histology using the Osteoarthritis Research Society International (OARSI) osteoarthritis (OA) cartilage histopathology assessment system. RESULTS: Significantly less cartilage degradation (decreased levels of COMP) was found in the combined hormone treated group in comparison with OVX group. Similarly, both hormonal treatment resulted in increased bone formation and decreased bone resorption i.e., a low overall bone turnover status (decrease in the serum OC and CTX-1 levels). CONCLUSIONS: Combined estrogen and progesterone therapy was found to be convincing in terms of reducing the severity of OA in this experimental model.
Animals
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Biological Markers/blood/metabolism
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Bone Remodeling/*drug effects
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Bone and Bones/chemistry/drug effects
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Cartilage/chemistry/*drug effects
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Collagen Type I/blood/metabolism
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Disease Models, Animal
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Estrogens/*pharmacology
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Extracellular Matrix Proteins/blood/metabolism
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Female
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Glycoproteins/blood/metabolism
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Histocytochemistry
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Hormone Replacement Therapy/*methods
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Osteoarthritis/blood/*drug therapy
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Osteocalcin/blood/metabolism
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Ovariectomy
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Progesterone/*pharmacology
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Rats
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Rats, Sprague-Dawley
8.Inhibitory effects of SRT1720 on the apoptosis of rabbit chondrocytes by activating SIRT1 via p53/bax and NF-κB/PGC-1α pathways.
Bi LIU ; Ming LEI ; Tao HU ; Fei YU ; De-Ming XIAO ; Hao KANG
Journal of Huazhong University of Science and Technology (Medical Sciences) 2016;36(3):350-355
SRT1720, a new discovered drug, was reported to activate silent information regulator 1 (SIRT1) and inhibit the chondrocyte apoptosis. However, the underlying mechanism remains elusive. In the present study, the chondrocytes were extracted from the cartilage tissues of New Zealand white rabbits, cultured in the presence of sodium nitroprusside (SNP) (2.5 mmol/L) and divided into five groups: 1, 5, 10, and 20 μmol/L SRT1720 groups and blank control group (0 μmol/L SRT1720). MTT assay was used to detect the chondrocyte viability and proliferation, and DAPI staining and flow cytometry to measure the chondrocyte apoptosis. The expression levels of SIRT1, p53, NF-κB/p65, Bax, and peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α) were detected by Western blotting and the expression levels of SIRT1, type II collagen, and aggrecan mRNA by RT-PCR. The results showed that in the SRT1720-treated groups, the nuclei of chondrocytes were morphologically intact and had uniform chromatin. In the blank control group, nuclear rupture into debris was observed in chondrocytes. With the SRT1720 concentration increasing, the chondrocyte viability increased, the apoptosis rate decreased, the protein expression levels of SIRT1 and PGC-1α and the mRNA expression levels of type II collagen and aggrecan increased ({ptP}<0.05), and the expression levels of p53, NF-κB and bax decreased (P<0.05). It was suggested that SRT1720 inhibits chondrocyte apoptosis by activating the expression of SIRT1 via p53/bax and NF-κB/PGC-1α pathways.
Aggrecans
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genetics
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metabolism
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Animals
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Apoptosis
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drug effects
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Cartilage, Articular
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cytology
;
drug effects
;
metabolism
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Cell Proliferation
;
drug effects
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Cell Survival
;
drug effects
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Chondrocytes
;
cytology
;
drug effects
;
metabolism
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Chromatin
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chemistry
;
drug effects
;
metabolism
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Collagen Type II
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genetics
;
metabolism
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Gene Expression Regulation
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Heterocyclic Compounds, 4 or More Rings
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pharmacology
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Nitroprusside
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toxicity
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Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
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genetics
;
metabolism
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Primary Cell Culture
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Rabbits
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Signal Transduction
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drug effects
;
genetics
;
Sirtuin 1
;
genetics
;
metabolism
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Transcription Factor RelA
;
genetics
;
metabolism
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Tumor Suppressor Protein p53
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genetics
;
metabolism
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bcl-2-Associated X Protein
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genetics
;
metabolism
9.Inflammatory cytokines and oxidative stress markers in the inhibition of osteoarthritis by curcumin.
Jun LIU ; Xiaole HE ; Ping ZHEN ; Shenghu ZHOU ; Xusheng LI
Journal of Zhejiang University. Medical sciences 2016;45(5):461-468
To observe the influence of matrix metalloproteinases-2 (MMP-2), monocyte chemoattractant protein-1 (MCP-1), CD47, L-selectin and advanced oxidation proteinproducts (AOPP) in osteoarthritis and the intervention of curcumin.A total of 20 male C57BL/6 mice (10.05-15.00 g) were randomly divided into control group, OA group, Cur25 group and Cur50 group (intraperitoneal injected 25 μmol/L or 50 μmol/L of curcumin everyday after modeling). After 4 weeks treatment, we observed the morphological changes of the gross specimen by immunohistochemical method, and observed the ultrastructure of cartilage tissue under electron microscope. The expression of MMP-2, MCP-1 and CD47 were detected by western blotting, and L-selectin and AOPP were detected by ELISA and spectrophotometer, respectively.In the cartilage tissue morphology, the chondrocytes of OA group showed obvious change, while Cur25 and Cur50 groups maintained the good cartilage cell membrane intact. Compared with control group, the expressions of MMP-2, MCP-1, L-selectin and AOPP in OA group, Cur25 group and Cur50 group were increased (all<0.05), while CD47 levels were decreased (all<0.05). Compared with OA group, the expressions of MMP-2, MCP-1, L-selectin and AOPP in Cur25 group and Cur50 group were decreased (all<0.05), while CD47 levels were increased (all<0.05), and such changes were more significant in Cur50 group (all<0.05).The MMP-2, MCP-1, CD47, L-selectin and AOPP are closely associated with the pathology course of OA. Curcumin has protection effect on cartilage, which can relieve joint cartilage degeneration, reduce cartilage inflammation and increase the metabolic activity of chondrocytes.
Advanced Oxidation Protein Products
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metabolism
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Animals
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Biomarkers
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CD47 Antigen
;
metabolism
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Cartilage
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chemistry
;
drug effects
;
pathology
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Chemokine CCL2
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metabolism
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Chondrocytes
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drug effects
;
pathology
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Curcumin
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administration & dosage
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pharmacology
;
Cytokines
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L-Selectin
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metabolism
;
Male
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Matrix Metalloproteinase 2
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metabolism
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Mice, Inbred C57BL
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Osteoarthritis
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genetics
;
pathology
;
physiopathology
;
Oxidative Stress
10.Experimental study of the isolation, culture and in chondrogenic differentiation of human bone mesenchymal stem cell.
Xi-min GUO ; Chang-yong WANG ; Yong-hong WANG ; Cui-mi DUAN ; Qiang ZHAO ; Da-ming SUN
Chinese Journal of Stomatology 2003;38(1):63-66
OBJECTIVETo study the isolation of human bone marrow mesenchymal stem cells (MSCs) and in vitro differentiation into chondrocytes as potential seed cell for condyle cartilage tissue engineering.
METHODSHuman MSCs were isolated by percoll solution from normal human bone marrow sample and cultured in flasks. Specific cell surface markers were identified by flow-cytometry. After the cells were treated with inductive medium containing insulin, transferrin, pyruvate, dexathemesone and TGF-beta for 7 - 14 days, microscopic, histological and immuno-histo-chemical studies were performed for chondrogenic phenotype identification.
RESULTSPrimary cultures of human MSCs express CD29 and CD44 positively and meanly, but CD34, CD45 and HLA-DR negatively. After 14 days of induction, the cells were positively stained by safranin O. Immunohistochemical analysis proved strong type II collagen expression.
CONCLUSIONSPercoll helps to generate a better isolation of MSCs from human bone marrow aspirates with a purity more above 95%. The isolated MSCs can be expanded and induced in vitro to differentiate into chondrocytes by inductive medium.
Bone Marrow Cells ; cytology ; Cartilage, Articular ; chemistry ; cytology ; Cell Culture Techniques ; methods ; Cell Differentiation ; drug effects ; Cells, Cultured ; Chondrocytes ; chemistry ; cytology ; Collagen Type II ; analysis ; Dexamethasone ; pharmacology ; Humans ; Immunohistochemistry ; Insulin ; pharmacology ; Mesoderm ; cytology ; Pyruvates ; pharmacology ; Stem Cells ; cytology ; Tissue Engineering ; methods ; Transferrin ; pharmacology ; Transforming Growth Factor beta ; pharmacology