Adiponectin Contributes to the Inflammatory Milieu in Hidradenitis Suppurativa

Introduction: Hidradenitis suppurativa (HS) is a severe chronic skin disease. Although the pathogenesis remains unclear, at the basis of HS there is an enhancement of the immune and inflammatory response together with a susceptibility to environmental factors. Cytokine dysregulation is crucial in HS severity and progression. Objectives: The aim of this study was to analyze serum levels of different cytokines focusing on adiponectin concentration and its oligomers in HS patients compared to both obese and healthy subjects. Methods: The concentrations of adiponectin and cytokines were measured using enzyme-linked immunosorbent assay (ELISA); the oligomeric distribution of adiponectin (low molecular weight (LMW), medium molecular weight (MMW) and high molecular weight (HMW) oligomers)was evaluated through Western Blotting analysis. Results: Total adiponectin is statistically higher in HS patients compared to matched controls and obese subjects. Interestingly, Adiponectin oligomerization state is altered in HS, with an increase of HMW oligomers. Serum levels of PDGF-BB, IL-1β, IL-5, Il-6, IL12, IL13, IL15, IL-17, GMCSF, INFγ, VEGF and MCP-1 are statistically higher while IL-1ra and RANTES levels are statistically lower in HS patients compared to healthy controls. Interestingly, adiponectin positively correlates with PDGF-BB, and IL-13. Conclusions: Our data confirmed that the complex network that links metabolism to immune homeostasis is dysregulated in HS and that adiponectin and its HMW oligomers are actively involved in this disease. In addition, the correlation between adiponectin and PDGF-BB, and IL-13 extends the role of this adipokine in modulation of the immune response, in particular regulating the innate immune system rather that the adaptive one. Further researches are needed to clarify the complex inflammatory milieu that characterizes HS syndrome.