What Fat Does to Arthritis

Less information is available on the role of adipokines in other connective tissue diseases such as systemic sclerosis (SSc). Serum levels of leptin seem to be decreased in patients with SSc, but further details, especially the role of adipokines in fibrosis, still need to be elucidated.¹⁶

Research in vasculitis has only addressed leptin thus far. In studies on antineutrophil cytoplasmic antibody-associated vasculitis, leptin levels were found to be significantly lower than those in healthy controls with or without body mass index (BMI) correction, and leptin levels were correlated negatively with disease activity.¹⁷ In contrast, in Behçet’s disease, leptin concentrations were found to be increased during active disease in comparison to inactive periods in this study.¹⁸ Along this line, resistin and IL-6 serum levels were significantly higher in patients with Behçet’s disease in comparison to healthy controls.

Conclusion

Taken together, studies on the pluripotent effects of adipokines in chronic inflammatory rheumatic diseases, as well as their role in matrix remodelling, are one of the most interesting current topics in rheumatology and other subspecialties involved in the care of patients with chronic inflammatory diseases.^5,8,13 While the role of the adipokines is complex, future studies may lead to novel therapeutic strategies or provide explanations for the benefits of current treatments as well as, importantly, the mechanisms for resistance to antirheumatic drugs. This future will also include the detailed evaluation of other members of the growing family of adipokines, (e.g. omentin, chemerin, cartonectin, and many others), which will also stimulate the cross-fertilization between various clinical disciplines (see Table 3).^19,20 While fat may seem to be an annoying tissue to patients, as studies of adipokines show, it can be a source of important factors that may have an impact on the pathogenesis of arthritis as well as many other diseases. the rheumatologist

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Table 3: The growing family of adipokines in the pathogenesis of rheumatic disease.

Dr. Müller-Ladner is chair and Drs. Frommer and Neumann are professors of internal medicine and rheumatology at Justus-Liebig-University Giessen in Bad Nauheim, Germany.

References

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