A recent study by Andrei Pernambucoand colleagues from the Federal University of Minas Gerais, Belo Horizonte, MG, Brazil is perhaps the first to document increased plasma levels of interleukin (IL)-17A in fibromyalgia (FM) patients.
Interleukin-17 and the T helper (Th)-17 cells play a key role in tissue inflammation and host defense and, recently, the Th17-pathway has been implicated in numerous inflammatory and autoimmune diseases. The concept that FM is an inflammatory state is not generally accepted. However, a recent systematic review of 25 selected articles reveals that FM patients have high serum levels of IL-1 receptor antagonist, IL-6 and IL-8 (Uçeyler N et al., BMC Musculoskelet Disord, 2011, 12:24).
In the study from Brazil, involving 58 women with FM, high plasma levels of IL-17 correlated positively with the levels of IL-2, TNF and IFN-γ, thus suggesting the involvement of inflammatory mechanisms in the development of this syndrome.
Interestingly, according to the authors, previous research, in other clinical conditions, indicates that IL-17A positively correlates with indices of pain, depression and anxiety, which are symptoms frequently reported by patients with FM.
The study may provide some new insights into the pathogenesis of FM, and may suggest an anti-inflammatory approach and/or new therapeutic target(s) for this common condition and syndrome.