Faculty Bibliography

Elevated levels of PGE(2) have been reported in synovial fluid and cartilage from patients with osteoarthritis (OA). However, the functions of PGE(2) in cartilage metabolism have not previously been studied in detail. To do so, we cultured cartilage explants, obtained from patients undergoing knee replacement surgery for advanced OA, with PGE(2) (0.1-10 muM). PGE(2) inhibited proteoglycan synthesis in a dose-dependent manner (maximum 25% inhibition (p < 0.01)). PGE(2) also induced collagen degradation, in a manner inhibitable by the matrix metalloproteinase (MMP) inhibitor ilomastat. PGE(2) inhibited spontaneous MMP-1, but augmented MMP-13 secretion by OA cartilage explant cultures. PCR analysis of OA chondrocytes treated with PGE(2) with or without IL-1 revealed that IL-1-induced MMP-13 expression was augmented by PGE(2) and significantly inhibited by the cycolooygenase 2 selective inhibitor celecoxib. Conversely, MMP-1 expression was inhibited by PGE(2), while celecoxib enhanced both spontaneous and IL-1-induced expression. IL-1 induction of aggrecanase 5 (ADAMTS-5), but not ADAMTS-4, was also enhanced by PGE(2) (10 muM) and reversed by celecoxib (2 muM). Quantitative PCR screening of nondiseased and end-stage human knee OA articular cartilage specimens revealed that the PGE(2) receptor EP4 was up-regulated in OA cartilage. Moreover, blocking the EP4 receptor (EP4 antagonist, AH23848) mimicked celecoxib by inhibiting MMP-13, ADAMST-5 expression, and proteoglycan degradation. These results suggest that PGE(2) inhibits proteoglycan synthesis and stimulates matrix degradation in OA chondrocytes via the EP4 receptor. Targeting EP4, rather than cyclooxygenase 2, could represent a future strategy for OA disease modification

Primary fibromyalgia, a poorly-understood chronic pain syndrome, is characterized by widespread musculoskeletal pain, nonrestorative sleep, fatigue, psychological distress, and specific regions of localized tenderness, all in the absence of otherwise apparent organic disease. While the etiology of fibromyalgia is unclear, accumulating data suggest that disordered central pain processing likely plays a role in the pathogenesis of symptoms. Although various pharmacological treatments have been studied and espoused for treating fibromyalgia, no single drug or group of drugs has proved to be particularly useful in treating fibromyalgia patients as a whole, and only one drug to date has earned U.S. Food and Drug Administration approval for treating the syndrome in the United States. This review critically and systematically evaluates clinical investigations of medicinal and nonmedicinal treatments for fibromyalgia dating from 1970 to 2007

Gout is the most common inflammatory arthritis in the United States, with more than three million sufferers. Management of gout has changed relatively little in the past 50 years, despite the fact that many gout patients have contraindications to one or more currently available gout therapies. However, recent insights into gout pathophysiology suggest that time is ripe for a change. This article reviews recent updates in the management of gout, including new insights into dietary management that may permit better control of hyuperuricemia. Also reviewed are the biological and clinical data behind newly-developed drugs for gout that are likely to receive serious consideration for FDA approval, and clinical use, in the foreseeable future

Traditional NSAIDs and some cyclooxygenase (COX)-2 inhibitors used to treat persons with osteoarthritis (OA) have adverse effects. However, traditional NSAIDs remain first-line therapy for some patients. The toxicities (eg, renal and GI effects) mostly are the result of COX inhibition. The ideal NSAID would inhibit COX-2 while sparing COX-1. The mechanisms for increased COX-2 cardiovascular toxicity remain less than fully understood. Several conservative strategies may help physicians use these agents effectively and safely. OA therapies under investigation (eg, inhibition of prostaglandin E synthases and disease-modifying osteoarthritis drugs) may render NSAIDs and COX-2 inhibitors obsolete

Both selective cyclooxygenase (COX)-2 inhibitors and non-steroidal anti-inflammatory drugs (NSAIDs) have been beneficial pharmacological agents for many patients suffering from arthritis pain and inflammation. However, selective COX-2 inhibitors and traditional NSAIDs are both associated with heightened risk of myocardial infarction. Possible pro-atherogenic mechanisms of these inhibitors have been suggested, including an imbalance in prostanoid production leaving the pro-aggregatory prostaglandins unopposed, but the precise mechanisms involved have not been elucidated. We explored the possibility that downregulation of proteins involved in reverse cholesterol transport away from atheromatous plaques contributes to increased atherogenesis associated with COX inhibition. The reverse cholesterol transport proteins cholesterol 27-hydroxylase and ATP-binding cassette transporter A1 (ABCA1) export cholesterol from macrophages. When mechanisms to process lipid load are inadequate, uncontrolled cholesterol deposition in macrophages transforms them into foam cells, a key element of atheromatous plaques. We showed that in cultured THP-1 human monocytes/macrophages, inhibition of COX-1, COX-2, or both reduced expression of 27-hydroxylase and ABCA1 message (real-time reverse transcription-polymerase chain reaction) and protein (immunoblot). The selective COX-2 inhibitor N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide (NS398) significantly reduced 27-hydroxylase and ABCA1 message (to 62.4% +/- 2.2% and 71.1% +/- 3.9% of control, respectively). Incubation with prostaglandin (PG) E2 or PGD2 reversed reductions in both of these cholesterol transport proteins induced by NS398. Cholesterol-loaded THP-1 macrophages showed significantly increased foam cell transformation in the presence of NS398 versus control (42.7% +/- 6.6% versus 20.1% +/- 3.4%, p = 0.04) as determined by oil red O staining. Pharmacological inhibition of COX in monocytes is involved in downregulation of two proteins that mediate cholesterol efflux: cholesterol 27-hydroxylase and ABCA1. Because these proteins are anti-atherogenic, their downregulation may contribute to increased incidence of cardiac events in patients treated with COX inhibitors. Reversal of inhibitory effects on 27-hydroxylase and ABCA1 expression by PGD2 and PGE2 suggests involvement of their respective signaling pathways. NS398-treated THP-1 macrophages show greater vulnerability to form foam cells. Increased cardiovascular risk with COX inhibition may be ascribed at least in part to altered cholesterol metabolism

Colchicine is the only drug known to effectively prevent familial Mediterranean fever (FMF) attacks, as well as FMF-associated amyloidosis. Unfortunately, colchicine is neither always effective nor always well tolerated, leaving some patients and their physicians with inadequate weaponry to fight this hazardous disease. We present a patient with recurrent episodes of abdominal, scrotal, and joint attacks, who was diagnosed with FMF and advised to take colchicine. Diarrhea prevented optimal treatment with this drug and led to a trial of etanercept, with resolution of FMF manifestations. This case adds to a growing body of evidence suggesting that tumor necrosis factor (TNF) blockade may result in resolution and prevention of further FMF attacks

Primary fibromyalgia is a common yet poorly understood syndrome characterized by diffuse chronic pain accompanied by other somatic symptoms, including poor sleep, fatigue, and stiffness, in the absence of disease. Fibromyalgia does not have a distinct cause or pathology. Nevertheless, in the past decade, the study of chronic pain has yielded new insights into the pathophysiology of fibromyalgia and related chronic pain disorders. Accruing evidence shows that patients with fibromyalgia experience pain differently from the general population because of dysfunctional pain processing in the central nervous system. Aberrant pain processing, which can result in chronic pain and associated symptoms, may be the result of several interplaying mechanisms, including central sensitization, blunting of inhibitory pain pathways, alterations in neurotransmitters, and psychiatric comorbid conditions. This review provides an overview of the mechanisms currently thought to be partly responsible for the chronic diffuse pain typical of fibromyalgia.

The production of nitric oxide (NO) by chondrocytes is increased in human osteoarthritis. The excessive production of NO inhibits matrix synthesis and promotes its degradation. Furthermore, by reacting with oxidants such as superoxide anion, NO promotes cellular injury and renders the chondrocyte susceptible to cytokine-induced apoptosis. Thus, NO produced by activated chondrocytes in diseased cartilage may modulate disease progression in osteoarthritis and should therefore be considered a potential target for therapeutic intervention.