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1.
Janelle-Montcalm A Boileau C Poirier F Pelletier JP Guévremont M Duval N Martel-Pelletier J Reboul P 《Arthritis research & therapy》2007,9(1):R20
In this study we examine the extracellular role of galectin-3 (gal-3) in joint tissues. Following intra-articular injection
of gal-3 or vehicle in knee joints of mice, histological evaluation of articular cartilage and subchondral bone was performed.
Further studies were then performed using human osteoarthritic (OA) chondrocytes and subchondral bone osteoblasts, in which
the effect of gal-3 (0 to 10 μg/ml) was analyzed. Osteoblasts were incubated in the presence of vitamin D3 (50 nM), which is an inducer of osteocalcin, encoded by an osteoblast terminal differentiation gene. Genes of interest mainly
expressed in either chondrocytes or osteoblasts were analyzed with real-time RT-PCR and enzyme immunoassays. Signalling pathways
regulating osteocalcin were analyzed in the presence of gal-3. Intra-articular injection of gal-3 induced knee swelling and
lesions in both cartilage and subchondral bone. On human OA chondrocytes, gal-3 at 1 μg/ml stimulated ADAMTS-5 expression
in chondrocytes and, at higher concentrations (5 and 10 μg/ml), matrix metalloproteinase-3 expression. Experiments performed
with osteoblasts showed a weak but bipolar effect on alkaline phosphatase expression: stimulation at 1 μg/ml or inhibition
at 10 μg/ml. In the absence of vitamin D3, type I collagen alpha 1 chain expression was inhibited by 10 μg/ml of gal-3. The vitamin D3induced osteocalcin was strongly inhibited in a dose-dependent manner in the presence of gal-3, at both the mRNA and protein
levels. This inhibition was mainly mediated by phosphatidylinositol-3-kinase. These findings indicate that high levels of
extracellular gal-3, which could be encountered locally during the inflammatory process, have deleterious effects in both
cartilage and subchondral bone tissues. 相似文献
2.
Kelitha Maxis Aline Delalandre Johanne Martel-Pelletier Jean-Pierre Pelletier Nicolas Duval Daniel Lajeunesse 《Arthritis research & therapy》2007,8(6):R181
Osteoarthritis (OA) is characterized by articular cartilage degradation and hypertrophic bone changes with osteophyte formation
and abnormal bone remodeling. Two groups of OA patients were identified via the production of variable and opposite levels
of prostaglandin E2 (PGE2) or leukotriene B4 (LTB4) by subchondral osteoblasts, PGE2 levels discriminating between low and high subgroups. We studied whether the expression of 5-lipoxygenase (5-LO) or 5-LO-activating
protein (FLAP) is responsible for the shunt from prostaglandins to leukotrienes. FLAP mRNA levels varied in low and high OA
groups compared with normal, whereas mRNA levels of 5-LO were similar in all osteoblasts. Selective inhibition of cyclooxygenase-2
(COX-2) with NS-398-stimulated FLAP expression in the high OA osteoblasts subgroup, whereas it was without effect in the low
OA osteoblasts subgroup. The addition of PGE2 to the low OA osteoblasts subgroup decreased FLAP expression but failed to affect it in the high OA osteoblasts subgroup.
LTB4 levels in OA osteoblasts were stimulated about twofold by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plus transforming growth factor-β (TGF-β), a situation corresponding to their effect on FLAP mRNA levels. Treatments with
1,25(OH)2D3 and TGF-β also modulated PGE2 production. TGF-β stimulated PGE2 production in both OA osteoblast groups, whereas 1,25(OH)2D3 alone had a limited effect but decreased the effect of TGF-β in the low OA osteoblasts subgroup. This modulation of PGE2 production was mirrored by the synthesis of COX-2. IL-18 levels were only slightly increased in a subgroup of OA osteoblasts
compared with normal; however, no relationship was observed overall between IL-18 and PGE2 levels in normal and OA osteoblasts. These results suggest that the shunt from the production of PGE2 to LTB4 is through regulation of the expression of FLAP, not 5-LO, in OA osteoblasts. The expression of FLAP in OA osteoblasts is
also modulated differently by 1,25(OH)2D3 and TGF-β depending on their endogenous low and high PGE2 levels. 相似文献
3.
Susana Jurado Natalia Garcia‐Giralt Adolfo Díez‐Pérez Pedro Esbrit Guy Yoskovitz Lídia Agueda Roser Urreizti Lluís Pérez‐Edo Guillem Saló Leonardo Mellibovsky Susana Balcells Daniel Grinberg Xavier Nogués 《Journal of cellular biochemistry》2010,110(2):304-310
The RANKL/RANK/OPG pathway is essential for bone remodeling regulation. Many hormones and cytokines are involved in regulating gene expression in most of the pathway components. Moreover, any deregulation of this pathway can alter bone metabolism, resulting in loss or gain of bone mass. Whether osteoblasts from osteoporotic and nonosteoporotic patients respond differently to cytokines is unknown. The aim of this study was to compare the effect of interleukin (IL)‐1β, proftaglandin E2 (PGE2), and transforming growth factor‐β1 (TGF‐β1) treatments on OPG and RANKL gene expression in normal (n = 11) and osteoporotic (n = 8) primary osteoblasts. OPG and RANKL mRNA levels of primary human osteoblastic (hOB) cell cultures were assessed by real‐time PCR. In all cultures, OPG mRNA increased significantly in response to IL‐1β treatment and decreased in response to TGF‐β1 whereas PGE2 treatment had no effect. RANKL mRNA levels were significantly increased by all treatments. Differences in OPG and RANKL responses were observed between osteoporotic and nonosteoporotic hOB: in osteoporotic hOB, the OPG response to IL‐1β treatment was up to three times lower (P = 0.009), whereas that of RANKL response to TGF‐β1 was five times higher (P = 0.002) after 8 h of treatment, as compared with those in nonosteoporotic hOBs. In conclusion, osteoporotic hOB cells showed an anomalous response under cytokine stimulation, consistent with an enhanced osteoclastogenesis resulting in high levels of bone resorption. J. Cell. Biochem. 110: 304–310, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
4.
Maria J Martíez-Calatrava Ivan Prieto-Potín Jorge A Roman-Blas Lidia Tardio Raquel Largo Gabriel Herrero-Beaumont 《Arthritis research & therapy》2012,14(3):R149-13
Introduction
The receptor activator nuclear factor-kappaB ligand (RANKL) diffuses from articular cartilage to subchondral bone. However, the role of chondrocyte-synthesized RANKL in rheumatoid arthritis-associated juxta-articular bone loss has not yet been explored. This study aimed to determine whether RANKL produced by chondrocytes induces osteoclastogenesis and juxta-articular bone loss associated with chronic arthritis.Methods
Chronic antigen-induced arthritis (AIA) was induced in New Zealand (NZ) rabbits. Osteoarthritis (OA) and control groups were simultaneously studied. Dual X-ray absorptiometry of subchondral knee bone was performed before sacrifice. Histological analysis and protein expression of RANKL and osteoprotegerin (OPG) were evaluated in joint tissues. Co-cultures of human OA articular chondrocytes with peripheral blood mononuclear cells (PBMCs) from healthy donors were stimulated with macrophage-colony stimulating factor (M-CSF) and prostaglandin E2 (PGE2), then further stained with tartrate-resistant acid phosphatase.Results
Subchondral bone loss was confirmed in AIA rabbits when compared with controls. The expression of RANKL, OPG and RANKL/OPG ratio in cartilage were increased in AIA compared to control animals, although this pattern was not seen in synovium. Furthermore, RANKL expression and RANKL/OPG ratio were inversely related to subchondral bone mineral density. RANKL expression was observed throughout all cartilage zones of rabbits and was specially increased in the calcified cartilage of AIA animals. Co-cultures demonstrated that PGE2-stimulated human chondrocytes, which produce RANKL, also induce osteoclasts differentiation from PBMCs.Conclusions
Chondrocyte-synthesized RANKL may contribute to the development of juxta-articular osteoporosis associated with chronic arthritis, by enhancing osteoclastogenesis. These results point out a new mechanism of bone loss in patients with rheumatoid arthritis. 相似文献5.
Holecki M Zahorska-Markiewicz B Janowska J Nieszporek T Wojaczyńska-Stanek K Zak-Gołab A Wiecek A 《Obesity (Silver Spring, Md.)》2007,15(8):1925-1929
Objective: To assess the influence of weight reduction therapy on serum osteoprotegerin (OPG) concentration in obese patients and compare these results with normal‐weight controls. Research Methods and Procedures: Forty‐three obese women (BMI, 36.7 ± 4.1 kg/m2; mean age, 50.1 ± 4.5 years) were studied. The control group consisted of 19 normal‐weight women (BMI, 24.2 ± 2.1 kg/m2; mean age, 53.8 ± 5.2 years). In all patients, serum concentrations of OPG, C telopeptide of type I collagen containing the cross‐linking site (CTX), osteocalcin, parathormone, 25‐(OH)‐D3 (vitamin D), and total calcium and phosphorus were assessed before and after a 3‐month weight reduction therapy. Results: In obese subjects, serum concentrations of OPG, 25‐(OH)‐D3, osteocalcin, total calcium, and phosphorus were significantly lower, and serum concentration of parathormone was significantly higher, before weight reduction therapy in comparison with normal‐weight controls. After weight reduction, a significantly higher serum concentration of 25‐(OH)‐D3 and CTX and significantly lower concentration of OPG were found. Discussion: Serum concentration of OPG was significantly lower in obese patients in comparison with normal‐weight controls. Weight reduction therapy resulted in further decrease in OPG serum concentrations. Therefore, OPG cannot be treated as a protective factor from bone loss in obese patients. 相似文献
6.
Insulin-like growth factor I enhances the formation of type I collagen in hydrocortisone-treated human osteoblasts 总被引:2,自引:0,他引:2
Kenneth B. Jonsson Sverker Ljunghall Olle Karlström Anna G. Johansson Hans Mallmin Östen Ljunggren 《Bioscience reports》1993,13(5):297-302
We have studied the effect of insulin-like growth factor I (IGF-I) on the formation of osteocalcin and type I collagen in isolated human osteoblasts. IGF-I at and above 0.1 nM stimulated the formation of type I collagen as measured by the type I procollagen carboxyterminal peptide (PICP), in human osteoblasts, incubated for 72 hrs in serumfree conditions. The secretion of osteocalcin was not affected by IGF-I while 1,25(OH)2 vitamin D3 significantly enhanced the formation of osteocalcin. When human osteoblast-like cells were incubated with hydrocortisone (1 M), a significant decrease in the release of both PICP and osteocalcin was seen. Addition of IGF-I to human osteoblasts also treated with hydrocortisone normalized the PICP-formation but did not affect the suppressed osteocalcin-formation. These data indicate that IGF-I reverses selective effects of hydrocortisone on bone. 相似文献
7.
Tachi K Takami M Zhao B Mochizuki A Yamada A Miyamoto Y Inoue T Baba K Kamijo R 《Cell and tissue research》2010,342(2):213-220
1α,25-dihydroxyvitamin D3 [1,25(OH)2D3] induces osteoclast formation via induction of receptor activator of NF-κB ligand (RANKL, also called TNF-related activation-induced cytokine: TRANCE) in osteoblasts. In cocultures of mouse bone marrow cells and osteoblasts, 1,25(OH)2D3 induced osteoclast formation in a dose-dependent manner, with maximum osteoclast formation observed at concentrations greater than 10?9 M of 1,25(OH)2D3. In the presence of bone morphogenetic protein 2 (BMP-2), the maximum formation of osteoclasts was seen with lower concentrations of 1,25(OH)2D3 (greater than 10?11 M), suggesting that BMP-2 enhances osteoclast formation induced by 1,25(OH)2D3. In addition, the expressions of RANKL mRNA and proteins were induced by 1,25(OH)2D3 in osteoblasts, and further upregulated by BMP-2. In mouse bone marrow cell cultures without 1,25(OH)2D3, BMP-2 did not enhance osteoclast differentiation induced by recombinant RANKL and macrophage colony-stimulating factor (M-CSF), indicating that BMP-2 does not target osteoclast precursors. Furthermore, BMP-2 up-regulated the expression level of vitamin D receptor (VDR) in osteoblasts. These results suggest that BMP-2 regulates mouse osteoclast differentiation via upregulation of RANKL in osteoblasts induced by 1,25(OH)2D3. 相似文献
8.
Funck-Brentano T Lin H Hay E Ah Kioon MD Schiltz C Hannouche D Nizard R Lioté F Orcel P de Vernejoul MC Cohen-Solal ME 《PloS one》2012,7(3):e33543
Objective
Subchondral bone modifications occur early in the development of osteoarthritis (OA). The level of bone resorption might impact cartilage remodeling. We therefore assessed the in vivo and in vitro effects of targeting bone resorption in OA and cartilage metabolism.Methods
OA was induced by meniscectomy (MNX) in ovariectomized osteopenic mice (OP) treated with estradiol (E2), pamidronate (PAM), or phosphate buffered saline (PBS) for 6 weeks. We assessed the subchondral bone and cartilage structure and the expression of cartilage matrix proteases. To assess the involvement of bone soluble factors in cartilage metabolism, supernatant of human bone explants pre-treated with E2 or PAM were transferred to cartilage explants to assess proteoglycan release and aggrecan cleavage. OPG/RANKL mRNA expression was assessed in bone explants by real-time quantitative PCR. The role of osteoprotegerin (OPG) in the bone-cartilage crosstalk was tested using an OPG neutralizing antibody.Results
Bone mineral density of OP mice and osteoclast number were restored by E2 and PAM (p<0.05). In OP mice, E2 and PAM decreased ADAMTS-4 and -5 expression, while only PAM markedly reduced OA compared to PBS (2.0±0.63 vs 5.2±0.95; p<0.05). OPG/RANKL mRNA was increased in human bone explants treated with both drugs (2.2–3.7-fold). Moreover, supernatants from bone explants cultured with E2 or PAM reduced aggrecan cleavage and cartilage proteoglycan release (73±8.0% and 80±22% of control, respectively, p<0.05). This effect was reversed with osteoprotegerin blockade.Conclusion
The inhibition of bone resorption by pamidronate in osteopenic mice alleviates the histological OA score with a reduction in the expression of aggrecanases. Bone soluble factors, such as osteoprotegerin, impact the cartilage response to catabolic factors. This study further highlights the importance of subchondral bone in the regulation of joint cartilage damage in OA. 相似文献9.
Bin Li Kaizhe Chen Niandong Qian Ping Huang Fangqiong Hu Tao Ding Xing Xu Qi Zhou Bo Chen Lianfu Deng Tianwen Ye Lei Guo 《Journal of cellular and molecular medicine》2021,25(11):5283-5294
Osteoarthritis (OA) is one of the most frequent chronic joint diseases with the increasing life expectancy. The main characteristics of the disease are loss of articular cartilage, subchondral bone sclerosis and synovium inflammation. Physical measures, drug therapy and surgery are the mainstay of treatments for OA, whereas drug therapies are mainly limited to analgesics, glucocorticoids, hyaluronic acids and some alternative therapies because of single therapeutic target of OA joints. Baicalein, a traditional Chinese medicine extracted from Scutellaria baicalensis Georgi, has been widely used in anti-inflammatory therapies. Previous studies revealed that baicalein could alleviate cartilage degeneration effectively by acting on articular chondrocytes. However, the mechanisms involved in baicalein-mediated protection of the OA are not completely understood in consideration of integrality of arthrosis. In this study, we found that intra-articular injection of baicalein ameliorated subchondral bone remodelling. Further studies showed that baicalein could decrease the number of differentiated osteoblasts by inhibiting pre-osteoblasts proliferation and promoting pre-osteoblasts apoptosis. In addition, baicalein impaired angiogenesis of endothelial cells and inhibited proliferation of synovial cells. Taken together, these results implicated that baicalein might be an effective medicine for treating OA by regulating multiple targets. 相似文献
10.
Jung Ha Kim Kabsun Kim Bang Ung Youn Jongwon Lee Inyoung Kim Hong-In Shin Haruhiko Akiyama Yongwon Choi Nacksung Kim 《The Journal of cell biology》2014,204(6):1063-1074
Osteoblasts not only control bone formation but also support osteoclast differentiation. Here we show the involvement of Kruppel-like factor 4 (KLF4) in the differentiation of osteoclasts and osteoblasts. KLF4 was down-regulated by 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) in osteoblasts. Overexpression of KLF4 in osteoblasts attenuated 1,25(OH)2D3-induced osteoclast differentiation in co-culture of mouse bone marrow cells and osteoblasts through the down-regulation of receptor activator of nuclear factor κB ligand (RANKL) expression. Direct binding of KLF4 to the RANKL promoter repressed 1,25(OH)2D3-induced RANKL expression by preventing vitamin D receptor from binding to the RANKL promoter region. In contrast, ectopic overexpression of KLF4 in osteoblasts attenuated osteoblast differentiation and mineralization. KLF4 interacted directly with Runx2 and inhibited the expression of its target genes. Moreover, mice with conditional knockout of KLF4 in osteoblasts showed markedly increased bone mass caused by enhanced bone formation despite increased osteoclast activity. Thus, our data suggest that KLF4 controls bone homeostasis by negatively regulating both osteoclast and osteoblast differentiation. 相似文献
11.
Gina Lisignoli Cristina Manferdini Katia Codeluppi Anna Piacentini Francesco Grassi Luca Cattini Giuseppe Filardo Andrea Facchini 《Journal of cellular physiology》2009,221(1):154-160
Subchondral bone remodeling in osteoarthritis (OA) and rheumatoid arthritis (RA) is mainly characterized by the formation of osteophytes/fibrosis and by the presence of infiltrating cells associated to bone resorption. In this study we analyzed CC (cysteine cysteine motif) chemokine ligand (CCL)20 and CC chemokine receptor (CCR)6 function in subchondral bone tissue and osteoblasts isolated from OA and RA patients. CCL20/CCR6 expression was evaluated by immunohistochemical techniques in bone tissue from OA and RA patients. CCL20‐functional tests were performed on osteoblasts isolated from OA and RA patients to evaluate enzymatic response and cell proliferation. Moreover, we assessed Akt phosphorylation as the major signaling pathway for CCL20. In bone tissue biopsies we found that osteoblasts from both OA and RA patients expressed CCR6 while CCL20 was expressed only by RA osteoblasts. Both CCR6 and CCL20 were highly expressed in osteocytes and mononuclear cells from only RA patients. CCL20‐stimulated OA osteoblasts showed a significant increase in β‐N‐acetylhexosaminidase release compared to RA. Conversely, a significant increase in cellular proliferation was found only in CCL20‐stimulated RA osteoblasts associated to Akt phosphorylation. These data were confirmed in bone tissue biopsies. This study demonstrates a different expression of CCL20‐positive osteoblasts in OA versus RA disease that seem to be associated with the presence of infiltrating mononuclear cells. Moreover, CCL20 stimulation resulted in a greater proliferative response in RA osteoblasts compared to OA osteoblasts, mediated by Akt signaling, while OA osteoblasts showed increased enzymatic activity, thus suggesting a differential role of this chemokine in OA and RA. J. Cell. Physiol. 221: 154–160, 2009. © 2009 Wiley‐Liss, Inc 相似文献
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13.
Juliana S. Cunha Vanessa M. Ferreira Edgar Maquigussa Marcelo A. Naves Mirian A. Boim 《Cell and tissue research》2014,358(1):249-256
Bone disease as a consequence of diabetes mellitus (DM) is not fully understood. The effects of high glucose (30 mM), high insulin (50 nM), or mannitol (30 mM; osmotic control) were evaluated on MC3T3-E1 cells (osteoblasts) in vitro. The mRNA and protein levels of parathyroid hormone (PTH) receptor (PTH1R), collagen I, RANKL, osteoprotegerin (OPG), alkaline phosphatase (ALP), and glucose transporter (GLUT1) were estimated by real-time polymerase chain reaction or Western blotting. The mineralization capacity was analyzed by von Kossa staining. High glucose induced overexpression of RANKL (2×) and OPG (30×), suggesting that RANKL-induced osteoclast activity might not be a dominant mechanism of bone disease in DM, since this increase was followed by increased OPG. Collagen I increased by 12×, indicating an excess of organic matrix production. The expression of ALP decreased by 50 %, indicating a deficit in mineralization capacity, confirmed by von Kossa staining. Mannitol induced similar effects as glucose suggesting that extracellular hyperosmolarity was able to stimulate organic matrix production. GLUT1 expression was not altered, and insulin did not reverse most of the effects of glucose, suggesting that glucose uptake by osteoblasts was not altered by high glucose. The data suggest that the bone fragility typical of DM is not a consequence of excessive bone reabsorption but is instead attributable to a defect in organic matrix mineralization. The heightened increase in OPG versus RANKL might cause a decrease in the bone-remodeling cycle. Osteoblasts appear to be more sensitive to extracellular hypertonicity than to the intracellular metabolic effects of hyperglycemia. 相似文献
14.
A. BittoH. Marini B.P. BurnettF. Polito R.M. LevyN. Irrera L. MinutoliE.B. Adamo F. Squadrito D. Altavilla 《Phytomedicine》2011,18(10):879-886
Genistein aglycone (GEN) has a favorable effect on bone loss. We investigated the effects of GEN alone or in combination with supplemental calcium and vitamin D3 in an animal model of bone loss to evaluate if there was additional benefit. Ovariectomized (OVX) and SHAM-OVX rats were used. OVX were divided into 12 groups and randomized to receive: GEN at 27, 54, 200, 500 or 1000 mg (human equivalent dose (HED)/day/ip injection alone or with calcium carbonate (Ca) (360 mg/kg/day/gavages) and vitamin D3 (D3) (50 IU/kg/day/gavages) or Ca/D3 without GEN or untreated for 6 weeks. SHAM-OVX were randomized into 7 groups and treated with: Ca and D3 alone or in combination with GEN (same doses as OVX), or left untreated. Bone mineral density (BMD), bone-alkaline phosphatase (b-ALP), collagen C-telopeptides (CTX), osteoprotegerin (OPG) and soluble receptor activator of NFκB ligand (sRANKL) were assessed. Femurs were excised and tested for breaking strength and histology. Uterine weight was analyzed to assess GEN's estrogenic effects on the SHAM-OVX.The most effective dose of GEN, independent of Ca/D3 supplementation, was 54 mg/day. Higher doses yielded no further improvement in bone biomarkers, histology or strength. Only 1000 mg/day HED of genistein produced statistically significant changes in uterine weight of the SHAM-OVX. This study suggests that 54 mg/day of GEN is the threshold dose for efficacy. In addition, supplemental calcium and vitamin D3, beyond normal dietary intake do not enhance the effects of genistein on improving measures of bone loss. This observation has implications regarding the use of calcium and vitamin D3 supplementation. 相似文献
15.
Mohan G Perilli E Kuliwaba JS Humphries JM Parkinson IH Fazzalari NL 《Arthritis research & therapy》2011,13(6):R210
Introduction
Osteoarthritis (OA) is a complex, multifactorial joint disease affecting both the cartilage and the subchondral bone. Animal models of OA aid in the understanding of the pathogenesis of OA and testing suitable drugs for OA treatment. In this study we characterized the temporal changes in the tibial subchondral bone architecture in a rat model of low-dose monosodium iodoacetate (MIA)-induced OA using in vivo micro-computed tomography (CT). 相似文献16.
Y Tanaka H K Schnoes C M Smith H F DeLuca 《Archives of biochemistry and biophysics》1981,210(1):104-109
A polar metabolite of vitamin D3 has been produced in vitro from either 1,25-dihydroxyvitamin D3 incubated with kidney homogenate from vitamin D-supplemented chickens or from 25,26-dihydroxyvitamin D3 incubated with vitamin D-deficient chicken kidney homogenate. This compound was isolated in pure form and identified as 1,25,26-trihydroxyvitamin D3 by ultraviolet absorption spectrophotometry and mass spectrometry. Furthermore, its periodate cleavage product comigrates with synthetic 1α-hydroxy-25-keto-27-norvitamin D3 on high-performance liquid chromatography. The 1,25,26-trihydroxyvitamin D3 is 0.1-0.01 as active as 1,25-dihydroxyvitamin D3 in the stimulation of intestinal calcium transport and bone calcium mobilization. 相似文献
17.
Anna Kats Natalija Gerasimcik Tuomas Nreoja Jonas Nederberg Simon Grenlv Ekaterina Lagnhed Suchita Desai Gran Andersson Tülay Yucel‐Lindberg 《Journal of cellular and molecular medicine》2019,23(2):1152-1163
Inflammatory mediator prostaglandin E2 (PGE2) contributes to bone resorption in several inflammatory conditions including periodontitis. The terminal enzyme, microsomal prostaglandin E synthase‐1 (mPGES‐1) regulating PGE2 synthesis is a promising therapeutic target to reduce inflammatory bone loss. The aim of this study was to investigate effects of mPGES‐1 inhibitors, aminothiazoles TH‐848 and TH‐644, on PGE2 production and osteoclastogenesis in co‐cultures of periodontal ligament (PDL) and osteoclast progenitor cells RAW 264.7, stimulated by lipopolysaccharide (LPS), and bone resorption in RANKL‐mediated peripheral blood mononuclear cells (PBMCs). PDL and RAW 264.7 cells were cultured separately or co‐cultured and treated with LPS alone or in combination with aminothiazoles. Multinucleated cells stained positively for tartrate‐resistant acid phosphatase (TRAP) were scored as osteoclast‐like cells. Levels of PGE2, osteoprotegerin (OPG) and interleukin‐6, as well as mRNA expression of mPGES‐1, OPG and RANKL were analysed in PDL cells. PBMCs were treated with RANKL alone or in combination with aminothiazoles. TRAP‐positive multinucleated cells were analysed and bone resorption was measured by the CTX‐I assay. Aminothiazoles reduced LPS‐stimulated osteoclast‐like cell formation both in co‐cultures and in RAW 264.7 cells. Additionally, aminothiazoles inhibited PGE2 production in LPS‐stimulated cultures, but did not affect LPS‐induced mPGES‐1, OPG or RANKL mRNA expression in PDL cells. In PBMCs, inhibitors decreased both osteoclast differentiation and bone resorption. In conclusion, aminothiazoles reduced the formation of osteoclast‐like cells and decreased the production of PGE2 in co‐cultures as well as single‐cell cultures. Furthermore, these compounds inhibited RANKL‐induced bone resorption and differentiation of PBMCs, suggesting these inhibitors for future treatment of inflammatory bone loss such as periodontitis. 相似文献
18.
Ramesh K. Wali Marc Bissonnette Kenneth Jiang Sharon M. Niedziela Sharad Khare Hemant K. Roy Michael D. Sitrin Thomas A. Brasitus 《Journal of cellular physiology》1995,162(2):172-180
Our laboratory has recently demonstrated that 1,25-dihydroxyvitamin D3(1,25(OH)2D3) rapidly stimulated membrane polyphosphoinositide breakdown and increased intracellular calcium, as well as activated protein kinase C (PKC) in vitamin D-sufficient rat colonocytes. These effects of 1,25(OH)2D3 were, however, lost in vitamin D-insufficient rats and restored by the in vivo repletion of 1,25(OH)2D3. In the present studies we have examined the ability of 1,25(OH)2D3 to stimulate the phosphorylation of colonic membrane proteins in intact D-sufficient cells. In addition, we investigated the effects of vitamin D status on the phosphorylation of these membrane proteins in broken cell preparations. These studies demonstrated that 1,25(OH)2D3 increased the phosphorylation of at least two colonic membrane proteins with apparent molecular weights of 42,000 (pp42) and 48,000 (pp48) in intact cells of vitamin D-sufficient rats. Moreover, in vitamin D-sufficient rats, treatment of colonocytes with 1,25(OH)2D3 or 12-Otertradecanoyl phorbol 13-acetate (TPA), a known activator of PKC, significantly increased the phosphorylation of pp42 and pp48 in broken cell preparations. The kinetics of these phosphorylations in response to 1,25(OH)2D3 were both rapid and transient. In addition, PKC19–36, a specific PKC inhibitor, decreased the phosphorylation of pp42 and pp48, whereas okadaic acid (OA), a type 1 and 2A protein phosphatase inhibitor, further augmented their phosphorylation in response to 1,25(OH)2D3. The isoelectric points of pp42 and pp48 were 5.79 and 5.97, respectively, and both were predominantly phosphorylated on threonine residues. In contrast to our findings in colonocytes from vitamin D-sufficient animals, basal phosphorylation of pp42 and pp48 were increased in membranes prepared from vitamin D-insufficient rats. Moreover, these phosphorylations failed to change in response to 1,25(OH)2D3-treatment of colonocytes from vitamin D-insufficient rats. The basal phosphorylation of each of these proteins was restored to control levels, as was their ability to respond to the direct addition of 1,25(OH)2D3 following the in vivo repletion of vitamin D-insufficient rats with this secosteroid. In summary, we have identified two acidic membrane proteins from rat colonocytes that are phosphorylated in both intact and broken cell preparations in response to 1,25(OH)2D3 treatment, an event modulated by vitamin D status and mediated, at least in part, by PKC. © 1995 Wiley-Liss, Inc. 相似文献
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20.
Steeve Kwan Tat Jean-Pierre Pelletier Nathalie Amiable Christelle Boileau Martin Lavigne Johanne Martel-Pelletier 《Arthritis research & therapy》2009,11(4):R119-10