Arthritis and rheumatism
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Arthritis and rheumatism · Dec 2010
Phenotypic alterations of neurons that innervate osteoarthritic joints in rats.
Pain is a prominent feature of osteoarthritis (OA). To further understand the primary mechanisms of nociception in OA, we studied the expression of the phenotype markers calcitonin gene-related peptide (CGRP), isolectin B4 (IB4), and neurofilament 200 (NF200) in sensory neurons innervating the OA knee joint in rats. ⋯ These results indicate that MIA-induced OA causes an up-regulation of CGRP in different subpopulations of primary afferent neurons in DRG due to a phenotypic switch and/or cell hypertrophy which may be functionally relevant in terms of the onset of pain in this pathologic condition.
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Arthritis and rheumatism · Nov 2010
Engagement of fatty acids with Toll-like receptor 2 drives interleukin-1β production via the ASC/caspase 1 pathway in monosodium urate monohydrate crystal-induced gouty arthritis.
The concept that intraarticular crystals of uric acid by themselves trigger episodes of painful gouty arthritis is inconsistent with the clinical reality. Patients with large deposits of monosodium urate monohydrate (MSU) crystals (tophi) do not necessarily experience gouty attacks. In fact, it is the excessive consumption of food or alcohol that elicits the inflammation of the acute gout attack. The aim of this study was to identify the precise mechanism that initiates flares of gouty arthritis. ⋯ The synergistic effect between FFAs and MSU crystals leads to ASC/caspase 1-driven IL-1β release. This mechanism could explain how constitutionally derived metabolic events initiate attacks of gout via the induction of IL-1β-mediated joint inflammation.
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Arthritis and rheumatism · Oct 2010
Meta AnalysisSimilar effects of disease-modifying antirheumatic drugs, glucocorticoids, and biologic agents on radiographic progression in rheumatoid arthritis: meta-analysis of 70 randomized placebo-controlled or drug-controlled studies, including 112 comparisons.
To define the differences in effects on joint destruction in rheumatoid arthritis (RA) patients between therapy with single and combination disease-modifying antirheumatic drugs (DMARDs), glucocorticoids, and biologic agents. ⋯ Treatment with DMARDs, glucocorticoids, biologic agents, and combination agents significantly reduced radiographic progression at 1 year, with a relative effect of 48-84%. A direct comparison between the combination of a biologic agent plus MTX and the combination of 2 DMARDs plus initial glucocorticoids revealed no difference. Consequently, biologic agents should still be reserved for patients whose RA is resistant to DMARD therapy. Future trials of the effects of biologic agents on RA should compare such agents with combination treatments involving DMARDs and glucocorticoids.
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Arthritis and rheumatism · Oct 2010
Alteration of sensory neurons and spinal response to an experimental osteoarthritis pain model.
To verify the biologic links between progressive cellular and structural alterations within knee joint components and development of symptomatic chronic pain that are characteristic of osteoarthritis (OA), and to investigate the molecular basis of alterations in nociceptive pathways caused by OA-induced pain. ⋯ Our results indicate that MIA-induced joint degeneration in rats generates an animal model that is suitable for mechanistic and pharmacologic studies on nociceptive pain pathways caused by OA, and provide key in vivo evidence that OA pain is caused by central sensitization through communication between peripheral OA nociceptors and the central sensory system. Furthermore, our data suggest a mechanistic overlap between OA-induced pain and neuropathic pain.
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Arthritis and rheumatism · Oct 2010
Thalamic atrophy associated with painful osteoarthritis of the hip is reversible after arthroplasty: a longitudinal voxel-based morphometric study.
Voxel-based morphometry (VBM) is a method of assessing brain gray matter volume that has previously been applied to various chronic pain conditions. From this previous work, it appears that chronic pain is associated with altered brain morphology. The present study was undertaken to assess these potential alterations in patients with painful hip osteoarthritis (OA). ⋯ Our findings confirm that gray matter volume decreases within the left thalamus in the presence of chronic pain and disability in patients with hip OA. The results also show that these thalamic volume changes reverse after hip arthroplasty and are associated with decreased pain and increased function. These findings have potential implications with regard to optimizing the timing of orthopedic interventions such as arthroplasty.