colchiceine and Gout

The aim of the present study was to establish the role of platelet‑activating factor acetyl hydrolase (PAF‑AH) in the resolution phase of gout using an established in vitro mononuclear cell model. The effects of signalling pathway inhibitors on PAF‑AH secretion, as well as the effects of the common treatments hydrocortisone and colchicine, an antibody against the anti‑inflammatory cytokine transforming growth factor β1 (TGFβ1), and the transcriptional inhibitor actinomycin D, were also investigated. The effect of recombinant PAF‑AH on cytokine secretion by these cells was also determined. Human peripheral blood‑derived monocytes were isolated and differentiated into macrophages. Monocytes and macrophages were stimulated with monosodium monohydrate urate (MSU) crystals or lipopolysaccharide in the presence or absence of AEG3482 [a c‑Jun N‑terminal kinase (JNK) inhibitor], MG132 (a proteasome inhibitor), hydrocortisone or colchicine. Cultures were then analysed for PAF‑AH secretion using ELISA. A 6‑fold upregulation of PAF‑AH secretion was observed following macrophage exposure to MSU crystals for 24 h (29.3±6 vs. 5.4±0.3 ng/ml unstimulated; P<0.05). Following 72 h, PAF‑AH levels decreased significantly (11.1±1.8; P<0.01). Secretion was further enhanced following pre‑treatment with the JNK protein kinase inhibitor AEG3482 prior to MSU crystal stimulation (P<0.05) and was abrogated when cells were preincubated with actinomycin D or the proteasome inhibitor MG132 (50, 100 and 200 µM). The addition of recombinant PAF‑AH (2.5‑10 ng/ml) to MSU crystal‑stimulated immature monocyte cultures significantly decreased pro‑inflammatory interleukin (IL)‑1β (unstimulated 687±124 vs. stimulated 113±30 pg/ml) and IL‑6 secretion (unstimulated 590±50 vs. stimulated 182±19 pg/ml). Treatment of MSU crystal‑stimulated macrophages with hydrocortisone (2 µM) also significantly decreased PAF‑AH release (P<0.05). Neutralising anti‑TGFβ1 addition decreased PAF‑AH dose‑dependently with the highest inhibition observed at 1 µg/ml (P<0.05). The results implicated that PAF‑AH may have an anti‑inflammatory role in the resolution phase of gout.

Topics: 1-Alkyl-2-acetylglycerophosphocholine Esterase; Colchicine; Cytokines; Gout; Humans; Hydrocortisone; Inflammation Mediators; Lipopolysaccharides; Macrophages; Monocytes; Transforming Growth Factor beta1; Uric Acid

Gout is one of the common inflammatory arthritis which affects many people for inflicting unbearable pain. Macrophage-mediated inflammation plays an important role in gout. The uptake of monosodium urate (MSU) crystals by macrophages can lead to activation of NOD-like receptors containing a PYD 3 (NLRP3) inflammasome, thus accelerating interleukin (IL)-1β production. Reactive oxygen species (ROS) promoted development of the inflammatory process through NLRP3 inflammasome. Our study aimed to find a food-derived compound to attenuate gout pain via the specific inhibition of the NLRP3 inflammasome in macrophages.. CD-1 mice were used to evaluate the degree of pain and the swelling dimension of joints after an intra-articular (IA) MSU injection in the ankle. The murine macrophage cell line Raw 264.7 was used to investigate the effects of procyanidins and the mechanism underlying such effects. Histological analysis was used to measure the infiltration of inflammatory cells. ROS produced from Raw 264.7 cells were evaluated by flow cytometry. Cell signaling was measured by Western blot assay and immunofluorescence.. Procyanidins significantly attenuated gout pain and suppressed ankle swelling. Procyanidins also inhibited MSU-induced activation of the NLRP3 inflammasome and increase of IL-1β. Furthermore, procyanidins decreased ROS levels in Raw 264.7 cells.. Suppression of the NLRP3 inflammasome in macrophages contributes to the amelioration of gout pain by procyanidins.

Topics: Animals; Ankle; Anti-Inflammatory Agents; Antioxidants; Colchicine; Cytokines; Gout; Grape Seed Extract; Inflammation; Lipopolysaccharides; Mice; NLR Family, Pyrin Domain-Containing 3 Protein; p38 Mitogen-Activated Protein Kinases; Pain; Phosphorylation; Proanthocyanidins; Reactive Oxygen Species; Signal Transduction; Spinal Cord; Uric Acid