[Different concentrations of specialized pro-resolving mediators in eosinophilic and non-eosinophilic chronic...

Objective: To investigate the difference of concentrations of specialized pro-resolving mediators (SPMs) derived from fatty acids in eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) and non-eosinophilic chronic rhinosinusitis with nasal polyps (nECRSwNP). Methods: A total of 36 patients with bilateral chronic rhinosinusitis with nasal polyps (CRSwNP) who underwent endoscopic nasal surgeries in Peking Union Medical College Hospital from May 2019 to September 2020 were enrolled, including 27 males and 9 females, with the age from 13 to 67 years. There were 23 cases of ECRSwNP and 13 cases of nECRSwNP. At the same time, 12 control subjects were enrolled. The concentrations of multiple SPMs, including lipoxins (LXA₄ and LXB₄), resolvins (RvD₁, RvD₂, RvD₃, RvD₅ and RvE₁), protectins (PDX) and maresins (Mar-1) in nasal polyps with different histological subtypes and normal nasal mucosa were analyzed using liquid chromatography-tandem mass spectrometry. The concentrations of SPMs between groups were compared using Mann-Whitney U test. Spearman's rank correlation coefficient was used to measure the correlation between the concentrations of SPMs in nasal polyps and tissue eosinophil counts. Results: The concentrations of RvD₂, RvD₃, RvD₅, LXA₄, LXB₄, Mar-1 and PDX in ECRSwNP group were significantly higher than that in controls (Z value was -2.276, -2.313, -3.371, -2.094, -2.051, -3.104 and -2.294, respectively, all P<0.05). The concentrations of RvD₂, RvD₅, Mar-1 and PDX in ECRSwNP group were significantly higher than those in nECRSwNP group (Z value was -2.175, -2.289, -2.243 and -2.124, respectively, all P<0.05). There was no significant difference in all these SPMs between nECRSwNP and controls (all P>0.05). The concentrations of RvD₂, RvD₃, RvD₅, LXB₄, Mar-1 and PDX in nasal polyps correlated positively with tissue eosinophil counts (r value was 0.443, 0.436, 0.371, 0.502, 0.340 and 0.386, respectively, all P<0.05). Conclusions: A varienty of SPMs are elevated in ECRSwNP. Dysregulation of fatty acid metabolism might play an important role in the chronic inflammation of ECRSwNP.