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- Bas, D. B., et al.
(författare)
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Collagen antibody-induced arthritis evokes persistent pain with spinal glial involvement and transient prostaglandin dependency
- 2012
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Ingår i: Arthritis & Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 64:12, s. 3886-3896
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Tidskriftsartikel (refereegranskat)abstract
- ObjectivePain is one of the most debilitating symptoms reported by rheumatoid arthritis (RA) patients. While the collagen antibody–induced arthritis (CAIA) model is used for studying the effector phase of RA pathologic progression, it has not been evaluated as a model for studies of pain. Thus, this study was undertaken to examine pain-like behavior induced by anticollagen antibodies and to assess the effect of currently prescribed analgesics for RA. In addition, the involvement of spinal glia in antibody-induced pain was explored.MethodsCAIA was induced in mice by intravenous injection of a collagen antibody cocktail, followed by intraperitoneal injection of lipopolysaccharide. Disease severity was assessed by visual and histologic examination. Pain-like behavior and the antinociceptive effect of diclofenac, buprenorphine, gabapentin, pentoxifylline, and JNK-interacting protein 1 were examined in mechanical stimulation experiments. Spinal astrocyte and microglia reactivity were investigated by real-time polymerase chain reaction and immunohistochemistry.ResultsFollowing the induction of CAIA, mice developed transient joint inflammation. In contrast, pain-like behavior was observed prior to, and outlasted, the visual signs of arthritis. Whereas gabapentin and buprenorphine attenuated mechanical hypersensitivity during both the inflammatory and postinflammatory phases of arthritis, diclofenac was antinociceptive only during the inflammatory phase. Spinal astrocytes and microglia displayed time-dependent signs of activation, and inhibition of glial activity reversed CAIA-induced mechanical hypersensitivity.ConclusionCAIA represents a multifaceted model for studies exploring the mechanisms of pain induced by inflammation in the articular joint. Our findings of a time-dependent prostaglandin and spinal glial contribution to antibody-induced pain highlight the importance of using appropriate disease models to assess joint-related pain.
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| 2. |
- Wigerblad, G., et al.
(författare)
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Autoantibodies to citrullinated proteins induce joint pain independent of inflammation via a chemokine-dependent mechanism
- 2016
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Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967 .- 1468-2060. ; 75:4, s. 730-738
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: An interesting and so far unexplained feature of chronic pain in autoimmune disease is the frequent disconnect between pain and inflammation. This is illustrated well in rheumatoid arthritis (RA) where pain in joints (arthralgia) may precede joint inflammation and persist even after successful anti-inflammatory treatment. In the present study, we have addressed the possibility that autoantibodies against citrullinated proteins (ACPA), present in RA, may be directly responsible for the induction of pain, independent of inflammation. METHODS: Antibodies purified from human patients with RA, healthy donors and murinised monoclonal ACPA were injected into mice. Pain-like behaviour was monitored for up to 28 days, and tissues were analysed for signs of pathology. Mouse osteoclasts were cultured and stimulated with antibodies, and supernatants analysed for release of factors. Mice were treated with CXCR1/2 (interleukin (IL) 8 receptor) antagonist reparixin. RESULTS: Mice injected with either human or murinised ACPA developed long-lasting pronounced pain-like behaviour in the absence of inflammation, while non-ACPA IgG from patients with RA or control monoclonal IgG were without pronociceptive effect. This effect was coupled to ACPA-mediated activation of osteoclasts and release of the nociceptive chemokine CXCL1 (analogue to human IL-8). ACPA-induced pain-like behaviour was reversed with reparixin. CONCLUSIONS: The data suggest that CXCL1/IL-8, released from osteoclasts in an autoantibody-dependent manner, produces pain by activating sensory neurons. The identification of this new pain pathway may open new avenues for pain treatment in RA and also in other painful diseases associated with autoantibody production and/or osteoclast activation.
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