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Approximately 12 mL of blood was collected from the antecubital vein by the standard venipuncture technique using a commercially produced vacuum-sealed kit. Tubes were centrifuged (Centrifugal machine, 3250RPM, Model Centurion, São Paulo, Brazil) at room temperature for 15 min at 2500 rotations per minute (≈ 1000×g). Serum was aliquoted (250 μL) and directly stored at − 80 °C until analyses by a blinded examiner. Serum levels of TGF-β and IGF-1 were obtained by regular enzyme-linked immunosorbent assays (ELISA). The circulating assessment of IL-1β, IL-6, IL-8, IL-10, and TNF-α was performed by a multiplexed flow cytometry method. The proteolytic activity was measured by analysis of metalloproteinases 2 and 9 activity using the zymographic method. Biological replicate samples of patients containing 1 μL of plasma were added to 1 μL of SDS (8%) (v:v). Metalloproteinases 2 and 9 activity were visualized as clear white bands against a blue background by densitometric scanning (ImageScanner III, Lab- Scan 6.0, Geneva, Switzerland). The analyses were performed in triplicate by a single-blinded examiner using ImageMaster 2D Platinum v7.0 (GeneBio) equipment, and the mean value of peak area was used in the final analysis (further details can be seen in Additional files 1 and 2).