Analysis of the tear MicroRNA levels in primary sjogren's syndrome

Abstract

Purpose : We investigated the expression of microRNAs (miRNAs) in the tears of patients with primary sjögren’s syndrome (pSS) compared to the tears of healthy controls. And we also examined the correlation between miRNAs expression and ocular parameters.

Methods : Eighteen tear samples were collected from pSS patients and eight from normal subjects at the Hanyang University Hospital. Clinical ophthalmologic assessments included Schirmer I test, tear film breakup time (tBUT) and ocular staining score (OSS). The expression of 43 different miRNAs were measured by real-time polymerase chain reaction. Differentially expressed miRNAs were stratified for fold regulation (FR) larger than ±2 and for significance of P < 0.05.

Results : For this study, 18 patients with primary SS (mean age 47.22 ± 11.56 years) and 8 controls (mean age 42.5 ± 11.78 years) were included. We found four miRNAs with significantly different expression in pSS patients compared to controls. Expression levels of miR-16-5p (FR=2.34, P=0.009) in patients with SS was significantly higher than that in controls. Expression levels of miR-30b-5p (FR=−2.14, P=0.023), miR-30c-5p (FR=−3.50, P=0.043), miR-203a-3p (FR=−2.28, P=0.031) in patients with primary SS were significantly lower than that in controls. All four miRNAs were not significantly correlated with OSS scores.

Conclusions : Our findings indicate that miR-16-5p, miR-30c-5p, miR-203a-3p, miR-30b-5p are deregulated in pSS. These miRNAs may play a role in the pathogenesis of pSS and serve as biomarkers for diagnosis of pSS.