• IMMUNE NETWORK
• /
• 제6권4호
• /
• pp.204-210
• /
• 2006

Background: Nitric oxide (NO) in articular chondrocytes regulates dedifferentiation and inflammatory responses by modulating MAP kinases. In this study, we investigated whether the Src kinase in chondrocytes regulates NO-induced dedifferentiation and cyclooxygenase-2 (COX-2) expression. Methods: Primary chondrocytes were treated with various concentrations of SNP for 24 h. The COX-2 and type II collagen expression levels were determined by immunoblot analysis, and prostaglandin $E_2\;(PGE_2)$ was determined by using a $PGE_2$ assay kit. Expression and distribution of p-Caveolin and COX-2 in rabbit articular chondrocytes and cartilage explants were determined by immunohistochemical staining and immunocytochemical staining, respectively. Results: SNP treatment stimulated Src kinase activation in a dose-dependent manner in articular chondrocytes. The Src kinase inhibitors PP2 [4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo(3,4-d)pyrimidine], a significantly blocked SNP-induced p38 kinase and caveolin-1 activation in a dose-dependent manner. Therefore, to determine whether Src kinase activation is associated with dedifferentiation and/or COX-2 expression and $PGE_2$ production. As expected, PP2 potentiated SNP-stimulated dedifferentiation, but completely blocked both COX-2 expression and $PGE_2$ production. And also, levels of p-Caveolin and COX-2 protein expression were increased in SNP-treated primary chondrocytes and osteoarthritic and rheumatoid arthritic cartilage, suggesting that p-Caveolin may playa role in the inflammatory responses of arthritic cartilage. Conclusion: Our previously studies indicated that NO caused dedifferentiation and COX-2 expression is regulated by p38 kinase through caveolin-1 (1). Therefore, our results collectively suggest that Src kinase regulates NO-induced dedifferentiation and COX-2 expression in chondrocytes via p38 kinase in association with caveolin-1.

• 대한의생명과학회지
• /
• 제15권4호
• /
• pp.343-347
• /
• 2009

Cytochalasin D (CD) is known as a disruptor of actin cytoskeleton architecture in chondrocytes. We have studied the role of CD in retinoic acid (RA) caused dedifferentiation and inflammation responses in rabbit articular chondrocytes. We have examined the effect of CD on RA induced dedifferentiation of chondrocytes. CD inhibited RA induced dedifferentiation determined by Western blot analysis and Alcian blue staining in rabbit articular chondrocytes. Also, CD additionally reduced inflammation response molecules such as cyclooxygenase-2 (COX-2) and prostaglandin $E_2$ ($PGE_2$) in RA treated cells. Treatment of CD reduced phosphorylation of p38 by treatment of RA. Inhibiton of p38kinase with SB203580 reduced expression of COX-2 and production of $PGE_2$ by treatment of CD in RA treated cells. But, Inhibiton of p38kinase with SB203580 did not any relationship with effect of CD on RA caused dedifferentiation. In summary, our results indicate that CD regulates RA reduced expression of COX-2 and production of PGE2 via p38kinase pathway.

• 대한수의학회지
• /
• 제33권2호
• /
• pp.189-198
• /
• 1993

The present study was undertaken to provide basic data on endochondral ossification for the axis in developing Miniature Schnauzers. This study was determined to the morphological features and development of growth plast in the axis of this experimental animals by histological and histochemical methods. The axis from 2 healthy Miniature Schnauzers(postnatal 6hr, 5week) was used. The obtained results were as follows : 1. In 5-week-old Miniature Schnauzer, the axis consisted of 4 separate ossification centers : centrum l, intercentrum 2, centrum 2 and epiphysis. Intercentrum 2 was intercalated between centrum 1 cranially, centrum 2 caudally. 2. The space of centrum 1 was more broader than the other ossification centers. 3. The zone of reserved chondrocytes was more extensive than the zone of proliferative chondrocytes, trabeculation was weakly observed, however, the proximal epiphyseal plate of axis was actively trabeculation observed in the zone of calcified chondrocytes. 4. Eighteen columns of chondrocytes were observed in the centrum 1 and five to seven columns of chondrocytes were observed in the centrum 2 of Miniature Schnauzer(postnatal 5 week) 5. A positive reaction to alcianophility was observed in all the territorial matrix at the zone of hypertrophic chondrocytes in this experimental animals.

• Physical Therapy Rehabilitation Science
• /
• 제2권1호
• /
• pp.21-26
• /
• 2013

Objective: The aim of this study was to investigate the effect of therapeutic ultrasound (US) of cell viability and inflammatory cytokine in rat articular chondrocyte cultures stimulated with lipopolysaccharide (LPS). Design: One group pretest-posttest design. Methods: Cultured chondrocytes were treated with US and/or LPS and assessed for viability, Tumor necrosis factor $(TNF)-{\alpha}$ and Interleukin (IL)-1 production. Results: Oxidative stress was induced in rat chondrocytes with LPS. The cell viability was decreased in chondrocytes after treatment with LPS. The viability revealed that low-intensity pulsed ultrasound (LIPUS) exerted no significant cytotoxicity in the rat chondrocyte. LIPUS inhibited decreased cell viability in the presence of LPS ($30{\mu}g/ml$) in a intensity dependent pattern at LIPUS (p<0.05). $TNF-{\alpha}$ production in the presence of LPS was also inhibited in a dose dependent manner (p<0.05 from $30mW/cm^2$). IL-1 production in the presence of LPS was inhibited as well (p<0.05 from $7.5mW/cm^2$). Conclusions: Our results demonstrate that US was the anti-inflammatory effect of chondrocytes. LIPUS may exert its anti inflammatory effects through inhibition of $TNF-{\alpha}$ and IL-1 synthesis. These results suggest that US have potential for use as a pain relief and reduce the articular destruction.

• 대한예방한의학회지
• /
• 제21권3호
• /
• pp.87-98
• /
• 2017

Objectives : The objective of present study is to evaluate anti-arthritic effects of dried pomegranate concentrate powders (PCP), Eucommiae Cortex aqueous (EC) and ethanolic (ECe) extracts, Achyranthis Radix aqueous (AR) and ethanolic (ARe) extracts on the primary cultured rat articular chondrocytes. Methods : MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium Bromide) assay was performed cytotoxic effect of test substances. In addition, anti-inflammatory effects were also observed on the lipopolysaccaride (LPS) treated chondrocytes through prostaglandin $E_2\;(PGE_2)$ production and 5-lipoxygenase (LPO) activities, and inhibitory effects on metalloproteinase (MMP)-2 and MMP-9 activities were observed on the recombinant human interleukin $(rhIL)-1{\alpha}$ treated chondrocytes with their extracellular matrix (ECM) related mRNA expressions - collagen type II, SOX9 and aggrecan. Results : As results, ECe and ARe showed obvious cytotoxicity against primary cultured rat articular chondrocytes at a dose level of 10 mg/ml, respectively. However, no obvious cytotoxic effects of PCP, EC and AR were demonstrated at a dose level of 10 mg/ml, on the primary cultured rat articular chondrocytes. In addition, treatment of LPS $50{\mu}g/ml$ induced significant increases of $PGE_2$ contents and 5-LPO activities indicating inflammatory responses of the primary cultured rat articular chondrocytes, and also decreases of cell viabilities, increases of MMP-2 and MMP-9 activities with decreases of extracellular matrix (ECM) related collagen type II, SOX9 and aggrecan mRNA expressions were observed by treatment of $rhIL-1{\alpha}$ 50 ng/ml, suggesting damages on the primary cultured rat articular chondrocytes and related ECM degradations. However, these inflammatory responses and related ECM degradations were inhibited by pretreatment of all test substances, in order of PCP > ECe > ARe > EC > AR, and $rhIL-1{\alpha}$ induced chondrocytes deaths are inhibited by treatment in order of PCP > EC > AR > ECe > ARe. Conclusions : Taken together, it is expected that mixed formulation of PCP as main components with appropriate proportion of EC and AR as additional components will be achieved a potent alternative medicinal food for osteoarthritis.

• Nutrition Research and Practice
• /
• 제10권6호
• /
• pp.569-574
• /
• 2016

BACKGROUND/OBJECTIVES: We investigated the anti-osteoarthritic effects of deer bone extract on the gene expressions of matrix metalloproteinases (MMPs) and collagen type II (COL2) in interleukin-$1{\beta}$-induced osteoarthritis (OA) chondrocytes. MATERIALS/METHODS: Primary rabbit chondrocytes were treated as follows: CON (PBS treatment), NC (IL-$1{\beta}$ treatment), PC (IL-$1{\beta}+100{\mu}g/mL$ glucosamine sulphate/chondroitin sulphate mixture), and DB (IL-$1{\beta}+100{\mu}g/mL$ deer bone extract). RESULTS: The results of the cell viability assay indicated that deer bone extract at doses ranging from 100 to $500{\mu}g/mL$ inhibits cell death in chondrocytes induced by IL-$1{\beta}$. Deer bone extract was able to significantly recover the mRNA expression of COL2 that was down-regulated by IL-$1{\beta}$ (NC: 0.79 vs. DB: 0.87, P < 0.05) and significantly decrease the mRNA expression of MMP-3 (NC: 2.24 vs. DB: 1.75) and -13 (NC: 1.28 vs. DB: 0.89) in OA chondrocytes (P < 0.05).CONCLUSIONS: We concluded that deer bone extract induces accumulation of COL2 through the down-regulation of MMPs in IL-$1{\beta}$-induced OA chondrocytes. Our results suggest that deer bone extract, which contains various components related to OA, including chondroitin sulphate, may possess anti-osteoarthritic properties and be of value in inhibiting the pathogenesis of OA.

• 생명과학회지
• /
• 제21권4호
• /
• pp.534-541
• /
• 2011

Retinoic acid (RA)는 Vitamin A의 대사산물로서 토끼 관절 연골세포의 탈분화를 유도하는 물질로 알려져 있다. 그러나 RA가 탈분화를 조절하는 정확한 메커니즘은 잘 알려져 있지 않다. 따라서, Nitric Oxide (NO)가 유도하는 탈분화에 미치는 RA의 분자적 기전에 관한 연구를 수행하였다. 그 결과, RA는 NO가 유도하는 탈분화를 촉진시키는 것을 확인 할 수 있었다. 이와 같은 결과는 Western blot analysis를 통해 연골세포 분화의 표지 단백질인 type II collagen 및 Sox-9의 발현양상을 통해 확인 할 수 있었으며, Alcian blue staining을 통해 연골세포의 기질을 구성하고 있는 단백질인 sulfated proteoglycan의 발현량을 통해서도 확인 할 수 있었다. 또한, RA는 NO 가 유도하는 ERK의 활성을 더욱 증가 시켰다. ERK의 억제자인 PD98059를 사용하여 ERK의 활성을 억제하였을 때 RA가 감소시키는 type II collagen 및 Sox-9의 발현과 sulfated proteoglycan의 생성 양상이 PD98059에 의해 다시 회복되는 것을 확인 할 수 있었다. 이러한 모든 결과를 종합해 볼 때, RA는 NO가 유도하는 탈분화를 ERK 신호전달경로를 통해 조절하는 것을 확인 할 수 있었다.

• Molecules and Cells
• /
• 제40권3호
• /
• pp.222-229
• /
• 2017

Adipose-derived stem cells (ADSCs) were previously considered to have an anti-inflammatory effect, and Interleukin-$1{\beta}$ ($IL-1{\beta}$) was found to be a pro-inflammatory factor in chondrocytes, but the mechanism underlying ADSCs and $IL-1{\beta}$ is unclear. In this study, we investigate whether P2X7 receptor (P2X7R) signalling, regulated by microRNA 373 (miR-373), was involved in the ADSCs and $IL-1{\beta}$ mediated inflammation in osteoarthritis (OA). Chondrocytes were collected from 20 OA patients and 20 control participants, and ADSCs were collected from patients who had undergone abdominal surgery. The typical surface molecules of ASDCs were detected by flow cytometry. The level of nitric oxide (NO) was determined by Griess reagent. Concentrations of prostaglandin E2 (PGE2), interleukin 6 (IL-6), matrix metallopeptidase 3 (MMP-3) were detected by enzyme-linked immunosorbent assay (ELISA). The expressions of IL-6, MMP-3, miR-373 and P2X7R were determined by real-time polymerase chain reaction (PCR), and Western blot was used to detect the protein expression of P2X7R. The typical potential characters of ADSCs were verified. In chondrocytes or OA tissues, the miR-373 expression level was decreased, but the P2X7R expression was increased. $IL-1{\beta}$ stimulation increased the level of inflammatory factors in OA chondrocytes, and ADSCs co-cultured with $IL-1{\beta}$-stimulated chondrocytes decreased the inflammation. OA chondrocytes transfected with the miR-373 inhibitor increased the inflammation level. The miR-373 mimic suppressed the inflammation by targeting P2X7R and regulated its expression, while its effect was reversed by overexpression of P2X7R. $IL-1{\beta}$ induced inflammation in OA chondrocytes, while ADSCs seemed to inhibit the expression of P2X7R that was regulated by miR-373 and involved in the anti-inflammatory process in OA.

• 대한의생명과학회지
• /
• 제15권2호
• /
• pp.113-118
• /
• 2009

Actin cytoskeletal architecture is believed to be a crucially important modulator of chondrocyte phenotype. 2DG(2-Dexoy-D-glucose) induces reorganization of actin cytoskeletal architecture in chondrocytes. In this study, we have investigated the effects of 2DG on dedifferentiation and inflammation via reorganization of cytoskeletal architecture in rabbit articular chondrocytes, with a focus on p38 kinase pathway. Treatment of 2DG alone reduced type II collagen and COX-2 expression in chondrocytes. But, 2DG reduced type II collagen was recovered by CD, disruptor of actin cytoskeletal architecture, whereas did not affect on COX-2 expression and production of $PGE_2$ compared with 2DG alone treated cells. Treatment of 2DG with JAS, inducer of cytoskeletal architecture polymerization, accelerated reduction of type II collagen expression and synthesis of proteoglycan but did not affect on COX-2 expression and production of $PGE_2$. Also, 2DG stimulated activation of p38 kinase. This result showed that 2DG regulates type II collagen but not cyclooxygenase-2 expression through reorganization of cytoskeletal architecture via p38 kinase pathway in rabbit articular chondrocytes.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
• /
• pp.421-424
• /
• 2000

Cartilage injuries are frequent nowadays. The previous surgical treatment of cartilage defect was limited. Another approach in the treatment of cartilage injuries is the use of reconstitute cartilage consisting of chondrocytes cultured in suitable biodegradable scaffolds. Current studies have demonstrated the compatibility of chondrocytes with different biomaterials and the chondrogenesis in various types of porous scaffolds. The cell ingrowth into the porous scaffolds is modulated by initial cell loading efficiency. Therefore, well-interconnected pore structure and even pore distribution of the scaffolds are essential for efficient cell seeding. According to our previous work, well-interconnected macroporous scaffolds can be prepared by gas-foaming/salt-leaching method using ammonium bicarbonate salt as porogen additives. In this work, primary chondrocytes were cultured in PLGA 65/35 scaffolds fabricated by using our method. Cells seeded in the scaffolds showed well distribution by agitated seeding method. Histochemical staining of proteoglycans present in the scaffolds was used to visualize the chondrocyte ingrowth in the scaffolds. At 3 weeks, the population of chondrocytes was increased for the most part of the scaffolds, and extra cellular matrix (ECM) secretion was increased as culture periods progressed.