Inflammation is Associated with Increased Functional Connectivity in Psoriasis

Background: Psoriasis is a systemic inflammation and immune dysregulation skin disorder and also classified as a type of psychosomatic disease that is highly related to psychological comorbidities. However, the relationship between peripheral inflammation and brain activity in psoriasis remain unclear. Objectives: To explore the relationship between peripheral inflammation and brain activity in psoriasis patients. Methods: A total of 12 psoriasis patients and 12 healthy controls were involved in this study, and all participants underwent resting-state functional magnetic resonance imaging (fMRI) scanning. And the whole-brain functional connectivity (FC) and fractional amplitude of low-frequency fuctuations (fALFF) were calculated. Additionally, the serum levels of pro-inflammatory cytokines in psoriasis patients, including IL-1β, IL-6, IL-17 and TNF-α, were detected. Then correlation analysis was performed to determine the relationship between abnormal fALFF and FC values and pro-inflammatory cytokines levels in paoriasis patients. Results: Compared with healthy controls, psoriasis patients showed increased fALFF in the Occipital_Inf_L and increased FC between the Frontal_Inf_Oper_L and Temporal_Mid_R, Cingulum_Post_L and Temporal_Inf_R, Parietal_Inf_L and Occipital_Sup_R, Angular_L and Occipital_Mid_L. Correlation analysis suggested that the level of IL-17 was both positively correlated with the fALFF values in the Occipital_Inf_L and FC values between Angular_L and Occipital_Mid_L. Conclusions: Our results demonstrated that the abnormal FC in psoriasis patients mainly occurs in the occipital lobe and temporal lobe. Moreover, increased fALFF and FC values of occipital lobe in Psoriasis Patients is positively correlated with their serum levels of IL-17. These results may provide a biological basis for revealing peripheral inflammation induced brain activity changes in psoriasis patients. Registry: ClinicalTrials.gov, ChiCTR2100043142, Registration date: 5 February 2021.