Effect of diacerein and rhein on the osteoclastic levels of metalloprotease-13 (MMP-13) and cathepsin K

Determination was performed in the conditioned medium for MMP-13 and on cell lysates for cathepsin K. Raw 264.7 cells were incubated for 5 days with RANKL (100 ng/mL), allowing the cells to differentiate into osteoclasts. After this period, the cells were incubated for 2 days together with RANKL in the presence or absence of interleukin-1-beta (IL-1β) (100 pg/mL) and diacerein or rhein (10 or 20 μg/mL). Data are expressed as fold changes compared with IL-1β-treated control, which was assigned a value of 1. Statistical analysis was performed versus IL-1β-treated control. RANKL, receptor activator of nuclear factor-κB ligand.<p><b>Copyright information:</b></p><p>Taken from "Diacerein inhibits the synthesis of resorptive enzymes and reduces osteoclastic differentiation/survival in osteoarthritic subchondral bone: a possible mechanism for a protective effect against subchondral bone remodelling"</p><p>http://arthritis-research.com/content/10/3/R71</p><p>Arthritis Research & Therapy 2008;10(3):R71-R71.</p><p>Published online 25 Jun 2008</p><p>PMCID:PMC2483463.</p><p></p

Representative immunohistochemical staining section for metalloprotease-13 (MMP-13) and cathepsin K in human osteoarthritis subchondral bone

MMP-13 was detected in the osteoblasts (Ob) as well as in the osteoclasts (Oc). Cathepsin K was detected only in osteoclasts. Original magnification, ×100.<p><b>Copyright information:</b></p><p>Taken from "Diacerein inhibits the synthesis of resorptive enzymes and reduces osteoclastic differentiation/survival in osteoarthritic subchondral bone: a possible mechanism for a protective effect against subchondral bone remodelling"</p><p>http://arthritis-research.com/content/10/3/R71</p><p>Arthritis Research & Therapy 2008;10(3):R71-R71.</p><p>Published online 25 Jun 2008</p><p>PMCID:PMC2483463.</p><p></p

Effect of diacerein and rhein on metalloprotease-13 (MMP-13) production in human osteoarthritis subchondral bone

Subchondral bone explants were incubated for 5 days with or without interleukin-1-beta (IL-1β) (5 ng/mL) and diacerein or rhein (10 or 20 μg/mL). Data are expressed as fold changes compared with IL-1β-treated control, which was assigned a value of 1. Statistical analysis was performed versus IL-1β-treated control.<p><b>Copyright information:</b></p><p>Taken from "Diacerein inhibits the synthesis of resorptive enzymes and reduces osteoclastic differentiation/survival in osteoarthritic subchondral bone: a possible mechanism for a protective effect against subchondral bone remodelling"</p><p>http://arthritis-research.com/content/10/3/R71</p><p>Arthritis Research & Therapy 2008;10(3):R71-R71.</p><p>Published online 25 Jun 2008</p><p>PMCID:PMC2483463.</p><p></p

Effect of diacerein and rhein on subchondral bone osteoblast intracellular mitogen-activated protein (MAP) kinase pathways

Subchondral bone osteoblasts were pre-incubated for 2 hours with diacerein or rhein at 20 μg/mL and incubated for 30 minutes in the presence or absence of interleukin-1-beta (IL-1β) (100 pg/mL). Levels of phosphorylated extracellular signal-regulated kinase-1/2 (ERK1/2), p38, and stress-activated protein kinase/c-jun N-terminal kinase (SAPK/JNK) (p46 and p54) MAP kinases were studied by Western blot and quantified by densitometry as described in Materials and methods. Data are expressed as fold changes compared with IL-1β-treated control, which was assigned a value of 1. Statistical analysis was performed versus IL-1β-treated control.<p><b>Copyright information:</b></p><p>Taken from "Diacerein inhibits the synthesis of resorptive enzymes and reduces osteoclastic differentiation/survival in osteoarthritic subchondral bone: a possible mechanism for a protective effect against subchondral bone remodelling"</p><p>http://arthritis-research.com/content/10/3/R71</p><p>Arthritis Research & Therapy 2008;10(3):R71-R71.</p><p>Published online 25 Jun 2008</p><p>PMCID:PMC2483463.</p><p></p

Signalling pathways induced by specific proteinase-activated receptor 2 (PAR-2) activation

<p><b>Copyright information:</b></p><p>Taken from "Activation of proteinase-activated receptor 2 in human osteoarthritic cartilage upregulates catabolic and proinflammatory pathways capable of inducing cartilage degradation: a basic science study"</p><p>http://arthritis-research.com/content/9/6/R121</p><p>Arthritis Research & Therapy 2007;9(6):R121-R121.</p><p>Published online 21 Nov 2007</p><p>PMCID:PMC2246240.</p><p></p> Representative Western blot of time and dose curves of PAR-2 signalling in osteoarthritic chondrocytes (= 3 or 4). Phosphorylated forms of Erk1/2 (p-Erk1/2) , p38 (p-p38) , and JNK (p-JNK) treated with PAR-2-activating peptide (PAR-2-AP) at 0 (-), 10, 100, and 400 μM in the absence or presence of interleukin 1 beta (IL-1β) (100 pg/mL) for 0 to 60 minutes . values indicate the comparison between the untreated (-) and the PAR-2-AP-treated chondrocytes. For p-Erk1/2, all of the times and concentrations showed a statistically significant increase (< 0.03). For p-p38, statistical significance was reached for each concentration at 5 and 15 minutes (< 0.03). values indicate the comparison between the untreated and the IL-1β-treated chondrocytes in the absence or presence of PAR-2-AP. Erk1/2, extracellular signal-regulated kinase 1/2; JNK, c-jun N-terminal kinase

Production of metalloproteinase (MMP)-1 , MMP-13 , and cyclooxygenase 2 (COX-2) following interleukin 1 beta (IL-1β) and specific proteinase-activated receptor 2 (PAR-2) activation

<p><b>Copyright information:</b></p><p>Taken from "Activation of proteinase-activated receptor 2 in human osteoarthritic cartilage upregulates catabolic and proinflammatory pathways capable of inducing cartilage degradation: a basic science study"</p><p>http://arthritis-research.com/content/9/6/R121</p><p>Arthritis Research & Therapy 2007;9(6):R121-R121.</p><p>Published online 21 Nov 2007</p><p>PMCID:PMC2246240.</p><p></p> Immunostaining data of osteoarthritic cartilage untreated (= 12) and treated with IL-1β (= 12), PAR-2-activating peptide (PAR-2-AP) 1 μM (= 3), PAR-2-AP 10 μM (= 4), PAR-2-AP 100 μM (= 4), and PAR-2-AP 400 μM (= 9). values indicate the comparison with the untreated (CTL) specimens

Proteinase-activated receptor 2 (PAR-2) gene expression and protein synthesis

<p><b>Copyright information:</b></p><p>Taken from "Activation of proteinase-activated receptor 2 in human osteoarthritic cartilage upregulates catabolic and proinflammatory pathways capable of inducing cartilage degradation: a basic science study"</p><p>http://arthritis-research.com/content/9/6/R121</p><p>Arthritis Research & Therapy 2007;9(6):R121-R121.</p><p>Published online 21 Nov 2007</p><p>PMCID:PMC2246240.</p><p></p> mRNA levels, as determined by real-time quantitative polymerase chain reaction as described in Materials and methods, in normal (= 4) and osteoarthritis (= 6) chondrocytes. PAR-2 immunostaining in normal (= 4) and osteoarthritis (= 4) cartilage. The percentage of positive chondrocytes represents the number of chondrocytes staining positive for PAR-2 of the total number of chondrocytes. Data are expressed as median and range and are presented as box plots, in which the boxes represent the first and third quartiles, the line within the box represents the median, and the lines outside the box represent the spread of values. values indicate the comparison of normal to osteoarthritis cartilage using the Mann-Whitney test. Representative sections showing PAR-2 immunostaining in normal and osteoarthritis cartilage. The arrows refer to positive chondrocytes

Histological score for mice four days after intra-articular galectin-3 (gal-3) injection

<p><b>Copyright information:</b></p><p>Taken from "Extracellular localization of galectin-3 has a deleterious role in joint tissues"</p><p>http://arthritis-research.com/content/9/1/R20</p><p>Arthritis Research & Therapy 2007;9(1):R20-R20.</p><p>Published online 27 Feb 2007</p><p>PMCID:PMC1860078.</p><p></p> Total score, cartilage score and bone histomorphometric score. Data are expressed as median and (range) and are presented in box plot, where the boxes represent the 1st and 3rd quartiles, the line within the box represents the median, and the lines outside the box represent the spread of the values. Control (Ctl): mice injected with PBS. versus control group; = four animals per group

Effects of exogenous galectin-3 (gal-3) on markers of subchondral bone osteoblasts

<p><b>Copyright information:</b></p><p>Taken from "Extracellular localization of galectin-3 has a deleterious role in joint tissues"</p><p>http://arthritis-research.com/content/9/1/R20</p><p>Arthritis Research & Therapy 2007;9(1):R20-R20.</p><p>Published online 27 Feb 2007</p><p>PMCID:PMC1860078.</p><p></p> Osteoblasts were treated with 1 or 10 μg/ml of recombinant human gal-3 in the presence or absence of vitamin D. Both alkaline phosphatase and osteocalcin expression were analyzed by real time RT-PCR. Insert illustrates the protein level of osteocalcin. = 4

Effects of exogenous galectin-3 (gal-3) on type I collagen expression in osteoblasts

<p><b>Copyright information:</b></p><p>Taken from "Extracellular localization of galectin-3 has a deleterious role in joint tissues"</p><p>http://arthritis-research.com/content/9/1/R20</p><p>Arthritis Research & Therapy 2007;9(1):R20-R20.</p><p>Published online 27 Feb 2007</p><p>PMCID:PMC1860078.</p><p></p> Osteoblasts were treated with 1 or 10 μg/ml of recombinant human gal-3 in the presence or not of vitamin D. Collagen type I α1 chain expression was analyzed by real time RT-PCR. *versus control (Ctl; without vitamin D3 or gal-3); **versus 1 μg gal-3 alone; = 4