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Human Synoviocytes (human + synoviocyte)
Selected AbstractsInhibition of synoviocytes proliferation by two types of c-myc antisense oligodeoxynucleotidesINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 2 2004Xinxin ZHAO Abstract Aim:, The c-myc proto-oncogene is over-expressed in synoviocytes from patients with rheumatoid arthritis (RA). For improving the inhibition of c-myc antisense oligodeoxynucleotides (AS ODN) on RA synoviocytes proliferation, we used two antisense sequences: one (antimyc-AUG AS ODN) targeting the initiation codon (AUG) and the next four codons on c-myc mRNA; another (antimyc-CRD AS ODN) targeting the coding region determinant (CRD) on c-myc mRNA to investigate if there was a difference on inhibiting synoviocytes proliferation. Methods:, Cultured human synoviocytes from patients with RA. The sequences were modified by phosphorothioates. Lipofectin was used as carrier. MTT assay was used to examine the inhibition of cell proliferation. Results:, Antimyc-AUG AS ODN and antimyc-CRD AS ODN both can inhibit synoviocytes proliferation dose-dependently. The maximum decrement of cell number was 40% at 2.5 µM and 48 h, 41.4% at 5 µM and 48 h, respectively. The action time of antimyc-AUG AS ODN inhibiting synoviocytes proliferation was earlier than that of antimyc-CRD AS ODN. ODN at high levels had non-sequence-specific cytotoxicity. Conclusions:, Both c-myc AS ODN are useful in inhibiting synoviocytes proliferation. [source] Prevention of cartilage degeneration and restoration of chondroprotection by lubricin tribosupplementation in the rat following anterior cruciate ligament transectionARTHRITIS & RHEUMATISM, Issue 8 2010Gregory D. Jay Objective To investigate whether cartilage degeneration is prevented or minimized following intraarticular injections of lubricin derived from human synoviocytes in culture, recombinant human PRG4 (rhPRG4), or human synovial fluid (SF) in a rat model of anterior cruciate ligament (ACL) injury. Methods Unilateral ACL transection (ACLT) was performed in Lewis rats (n = 45). Nine animals were left untreated. The remaining rats were given intraarticular injections (50 ,l/injection) of either phosphate buffered saline (PBS) (n = 9), human synoviocyte lubricin (200 ,g/ml; n = 9), rhPRG4 (200 ,g/ml; n = 9), or human SF lubricin (200 ,g/ml; n = 9) twice weekly beginning on day 7 after injury. Joints were harvested on day 32 after injury. Histologic analysis was performed using Safranin O,fast green staining, and articular cartilage degeneration was graded using the Osteoarthritis Research Society International (OARSI),modified Mankin criteria. Histologic specimens were immunoprobed for lubricin and sulfated glycosaminoglycans. A 24-hour urine collection was performed on days 17 and 29 postinjury, and urinary C-terminal telopeptide of type II collagen (CTX-II) levels were measured. Results Treatment with human synoviocyte lubricin resulted in significantly lower OARSI scores for cartilage degeneration compared with no treatment or PBS treatment (P < 0.05). Increased immunostaining for lubricin in the superficial zone chondrocytes and on the surface of cartilage was observed in lubricin-treated, but not untreated or PBS-treated, joints. On day 17, urinary CTX-II levels in human synoviocyte lubricin, and human SF lubricin,treated animals were significantly lower than those in untreated animals (P = 0.005 and P = 0.002, respectively) and in PBS-treated animals (P = 0.002 and P < 0.001, respectively). Conclusion After treatment with any of the 3 types of lubricin evaluated in this study, a reduction in cartilage damage following ACLT was evident, combined with a reduction in type II collagen degradation. Our findings indicate that intraarticular lubricin injection following an ACL injury may be beneficial in retarding the degeneration of cartilage and the development of posttraumatic OA. [source] Chondroitin sulfate increases hyaluronan production by human synoviocytes through differential regulation of hyaluronan synthases: Role of p38 and AktARTHRITIS & RHEUMATISM, Issue 3 2009Maha David-Raoudi Objective To uncover the mechanism by which chondroitin sulfate (CS) enhances hyaluronan (HA) production by human osteoarthritic (OA) fibroblast-like synoviocytes (FLS). Methods The production of HA was investigated by exposing human OA FLS to CS in the presence or absence of interleukin-1, (IL-1,). HA levels were determined by enzyme-linked immunosorbent assay, and levels of messenger RNA (mRNA) for HA synthase 1 (HAS-1), HAS-2, and HAS-3 were determined by real-time polymerase chain reaction analysis. The effect of CS and IL-1, on signaling pathways was assessed by Western blotting. Specific inhibitors were used to determine their effects on both HA production and HAS expression. The molecular size of HA was analyzed by high-pressure liquid chromatography. Results CS increased HA production by FLS through up-regulation of the expression of HAS1 and HAS2. This was associated with activation of ERK-1/2, p38, and Akt, although to a lesser extent. Both p38 and Akt were involved in CS-induced HA accumulation. IL-1, increased HA production and levels of mRNA for HAS1, HAS2, and HAS3. CS enhanced the IL-1,,induced level of HAS2 mRNA and reduced the level of HAS3 mRNA. IL-1,,induced activation of p38 and JNK was slightly decreased by CS, whereas that of ERK-1/2 and Akt was enhanced. More high molecular weight HA was found in CS plus IL-1,,treated FLS than in FLS treated with IL-1, alone. Conclusion CS stimulates the synthesis of high molecular weight HA in OA FLS through up-regulation of HAS1 and HAS2. It reduces the IL-1,,enhanced transcription of HAS3 and increases the production of HA of large molecular sizes. These effects may be beneficial for maintaining viscosity and antiinflammatory properties in the joint. [source] Expression and functional role of adenosine receptors in regulating inflammatory responses in human synoviocytesBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2010K Varani Background and purpose:, Adenosine is an endogenous modulator, interacting with four G-protein coupled receptors (A1, A2A, A2B and A3) and acts as a potent inhibitor of inflammatory processes in several tissues. So far, the functional effects modulated by adenosine receptors on human synoviocytes have not been investigated in detail. We evaluated mRNA, the protein levels, the functional role of adenosine receptors and their pharmacological modulation in human synoviocytes. Experimental approach:, mRNA, Western blotting, saturation and competition binding experiments, cyclic AMP, p38 mitogen-activated protein kinases (MAPKs) and nuclear factor (NF)-,B activation, tumour necrosis factor , (TNF-,) and interleukin-8 (IL-8) release were assessed in human synoviocytes isolated from patients with osteoarthritis. Key results:, mRNA and protein for A1, A2A, A2B and A3 adenosine receptors are expressed in human synoviocytes. Standard adenosine agonists and antagonists showed affinity values in the nanomolar range and were coupled to stimulation or inhibition of adenylyl cyclase. Activation of A2A and A3 adenosine receptors inhibited p38 MAPK and NF-,B pathways, an effect abolished by selective adenosine antagonists. A2A and A3 receptor agonists decreased TNF-, and IL-8 production. The phosphoinositide 3-kinase or Gs pathways were involved in the functional responses of A3 or A2A adenosine receptors. Synoviocyte A1 and A2B adenosine receptors were not implicated in the inflammatory process whereas stimulation of A2A and A3 adenosine receptors was closely associated with a down-regulation of the inflammatory status. Conclusions and implications:, These results indicate that A2A and A3 adenosine receptors may represent a potential target in therapeutic modulation of joint inflammation. [source] | ||||||||||