Peripheral expression of ANRIL is increased in axial spondyloarthritis patients, and particularly in females

Abstract AxSpA is the prototypical form of a group of diseases recognized as spondyloarthritis characterized by systemic inflammation and pathological osteogenesis with hundreds of long non-coding RNAs (LncRNAs) deregulated in this disease. ANRIL is an inflammatory-related lncRNA, but its relation to inflammation is contradictory and its involvement in axSpA disease is unknown. We examined the peripheral expression of ANRIL in axSpA patients and healthy controls. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) was used to measure disease activity. NSAID intake score was calculated based on ASAS recommendation. Transcript levels of ANRIL were significantly higher in patients than in control. However, the difference was more eminent and more significant when only comparing female axSpA patients vs sex-matched controls. Moreover, no significant different level of ANRIL transcript was found between male axSpA patients compared to controls, nor to sex- matched controls. While the expression of ANRIL was higher in the active BASDAI group compared to the inactive BASDAI group, it didn't reach a significant level (P value = 0.16). No significant difference between the expressions of ANRIL in female axSpA vs male axSpA subjects was found. No correlation between the levels of ANRIL transcripts and NSAID intake score, and ANRIL expression and age was found, indicating that they didn't have a significant effect on ANRIL expression. The levels of ANRIL transcript could differentiate axSpA patients compared to controls, notably when excluding males of both groups. ANRIL expression was significantly increased in the active disease compared to controls. The current study presents the dysregulation of ANRIL expression in peripheral blood of axSpA patients. However, the dysregulation seems to be mostly related to female subjects. Furthermore, we demonstrated that ANRIL is not significantly affected neither by age nor by NSAID intake.