Exploring the role of long non-coding RNAs in periodontitis

Recent studies have underscored the role of long non-coding RNAs (lncRNAs) in the pathophysiology of several immune-related conditions such as periodontitis. In the current study, we aimed at exploration of the role of four lncRNAs (UCA1, NEAT1, FAS-AS1 and NKILA) in this disorder. We compared expression of these genes between blood and gingival samples obtained from patients with periodontitis and normal subjects. Expression of UCA1 was significantly lower in peripheral blood of patients compared with controls (Posterior beta of RE = - 2.069, P value = .029). When dividing samples based on the gender of individuals, the difference was significant between female patients and female controls (Posterior beta of RE = -1.895, P value = .049), but not between male subjects. There was no significant difference in tissue expression of UCA1 between cases and controls. Expression of FAS-AS1 was significantly lower in peripheral blood of patients compared with controls (Posterior beta of RE = -7.065, P value = .001). The difference was significant among both male and female patients versus sex-matched controls (Posterior beta of RE = -8.166, P value = .006 and Posterior beta of RE = -5.118, P value = .026, respectively). Yet, expression of this lncRNA was not different between tissues samples obtained from patients and controls. Expression of NEAT1 was significantly higher in tissue samples obtained from patients compared with controls (Posterior beta of RE = 3.386, P value = .043). Such pattern was also observed in tissue samples obtained from male persons (Posterior beta of RE = 6.417, P value = .017) but not female persons. Surprisingly, expression of NEAT1 was lower in patients' blood samples compared with controls (Posterior beta of RE = -2.99, P value = .01) and in blood samples obtained from female patients compared with sex-matched controls (Posterior beta of RE = -2.991, P value = .01). Expression of NKILA was significantly higher in both tissue samples and blood samples obtained from patients compared with controls (Posterior beta of RE = 7.974, P value < .0001 and Posterior beta of RE = 5.122, P value = .001). Difference in tissue expression of this lncRNA was significant in both male and female patients compared with sex-matched controls, but blood expression of this lncRNA was only different between female patients and female controls. There were significant correlations between tissue expressions of UCA1 and NEAT1 (r = 0.79, P < .001), tissue expressions of FAS-AS1 and NEAT1 (r = 0.76, P < .001) and blood expressions of UCA1 and NEAT1 (r = 0.75, P < .001) in patients with periodontitis. The current study supports the role of lncRNAs in the pathophysiology of periodontitis and potentiates them as putative biomarkers for this disorder.