Abnormal T-cell function in patients with psoriatic arthritis: evidence for decreased interleukin 2 production

Complexities in Genetics of Psoriatic Arthritis

PURPOSE OF THE REVIEW

To provide a general overview and current challenges regarding the genetics of psoriatic disease. With the use of integrative medicine, multiple candidate loci identified to date in psoriatic disease will be annotated, summarized, and visualized. Recent studies reporting differences in genetic architecture between psoriatic arthritis and cutaneous-only psoriasis will be highlighted.

RECENT FINDINGS

Focusing on functional pathways that connect previously identified genetic variants can increase our understanding of psoriatic diseases. The genetic architecture differs between psoriatic arthritis and cutaneous-only psoriasis with arthritis-specific signals in linkage disequilibrium independent of the published psoriasis signals. Integrative medicine is helpful in understanding cellular mechanisms of psoriatic diseases. Careful selection of the psoriatic disease cohort has translated into mechanistic differences among psoriatic arthritis and cutaneous psoriasis.

Therapy with cyclosporine in psoriatic arthritis

OBJECTIVE

To evaluate the efficacy and toxicity of cyclosporin A (CsA) in the treatment of patients with psoriatic arthritis (PsA).

METHODS

We reviewed the literature dealing with CsA treatment of PsA.

RESULTS

In the 1980s, some studies evaluating CsA in severe cases of psoriasis documented an improvement in the associated arthritis. Subsequently, open prospective studies included patients with active peripheral arthritis. Using initial CsA dose of 3 to 6 mg/kg/day, improvement in the clinical parameters was noted. A controlled trial showed that CsA and methotrexate (MTX) are equally effective treatment for PsA. CsA and MTX combination was effective in PsA patients resistant to previous second-line therapy. No studies have evaluated the efficacy of CsA on axial disease and on the progression of radiological damage. The most important side effect was nephrotoxicity. However, of 170 CsA-treated patients in 16 studies, only 10 (6%) discontinued the drug because of renal side effects.

CONCLUSIONS

CsA seems to be an effective and safe therapy for PsA. However, controlled studies on large number of patients are necessary.

The role of tumor necrosis factor-alpha in the pathogenesis of anorexia and bulimia nervosa, cancer cachexia and obesity

In this paper a new immunological model of anorexia and bulimia nervosa will be presented in which the inflammatory cytokines are conceived as the fundamental regulators of body metabolism. This conception differs from the conventional view in which the inflammatory cytokines are perceived primarily as peptide molecules utilized by the immune system to control infection, inflammation and tissue or neuronal damage. Given that the inflammatory cytokines are also fundamental regulators of body metabolism, when they become dysregulated they create physiological chaos which results in the development of a number of autoimmune, metabolic and psychiatric disorders. In this proposed immunological model of anorexia and bulimia nervosa, elevated tumor necrosis factor-alpha features as the primary cause of these conditions. Pathophysiological parallels are drawn between anorexia nervosa and cancer cachexia in terms of the causal role the cytokines, neuropeptides and neurotransmitters play in the manifestation of shared symptoms. These shared symptoms include elevated tumour necrosis factor-alpha, down-regulated interleukin-2 and interleukin-4 and depletion of lean body mass. Furthermore, the following neuropeptides are dysregulated in both anorexia nervosa and cancer cachexia: vasoactive intestinal peptide, cholecystokinin, corticotropin-releasing factor, neuropeptide Y, peptide YY and beta-endorphin. In addition, in anorexia and bulimia nervosa, secretion of the neurotransmitter serotonin is inhibited while norepinephrine is enhanced. It will be argued that the causal interplay between the cytokines, neuropeptides and neurotransmitters initiates a cascade of biochemical events which may result in either anorexia or bulimia nervosa, or cancer cachexia. The extent to which these inflammatory cytokines, neuropeptides and neurotransmitters are causally efficacious in the pathogenesis of other autoimmune disorders, such as diabetes mellitus and rheumatoid arthritis, will also be addressed.