MicroRNA expression in inflamed and noninflamed gingival tissues from Japanese patients

Abstract

Periodontitis is a chronic inflammatory disease caused by specific bacteria and viruses. Local, systemic, and environmental factors affect the rate of disease progression. Immune responses to bacterial products, and the subsequent production of inflammatory cytokines, are crucial in the destruction of periodontal tissue. MicroRNAs (miRNAs) are a class of small RNAs that control various cell processes by negatively regulating protein-coding genes. In this study, we compared miRNA expression in inflamed and noninflamed gingival tissues from Japanese dental patients. Total RNAs were isolated from inflamed and noninflamed gingival tissues. miRNA expression profiles were examined by an miRNA microarray, and the data were analyzed by GeneSpring GX, Ingenuity Pathways Analysis, and the TargetScan databases. Observed miRNA expression levels in inflamed gingiva were confirmed by real-time PCR. The three most overexpressed (by >2.72-fold) miRNAs were hsa-miR-150, hsa-miR-223, and hsa-miR-200b, and the three most underexpressed (by <0.39-fold) miRNAs were hsa-miR-379, hsa-miR-199a-5p, and hsa-miR-214. In IPA analysis, hsa-miR-150, hsa-miR-223, and hsa-miR-200b were associated with inflammatory disease, organismal injury, abnormalities, urological disease, and cancer.

Effects of miR-223 on expression of IL-1β and IL-6 in human gingival fibroblasts

“…We have previously reported that miR-223 expression is significantly upregulated in inflamed gingiva in comparison with non-inflamed gingiva (17). To determine whether inflammatory cytokines can induce miR-223 expression in HGF, we stimulated HGF with IL-1β (1 ng/ mL), IL-6 (1 ng/mL), and TNF-α (10 ng/mL) for 24 h and confirmed that miR-223 expression was induced by these cytokines (Fig.…”

“…Cell culture HGF were cultured in 5% CO 2 and 95% air at 37°C in DMEM medium containing 10% FCS as described previously (17)(18)(19). The Ethics Committee of Nihon University School of Dentistry at Matsudo approved the study (EC03-041, EC10-040, EC14-023), and a consent form was obtained from each patient after all the protocol had been explained.…”

“…Several studies have demonstrated that a range of miRNAs are closely associated with inflammatory responses (14)(15)(16). We have previously reported that the three most overexpressed miRNAs in inflamed gingiva from Japanese patients with chronic periodontitis (CP) were hsa-miR-150, hsa-miR-223 and hsa-miR-200b, and that IL-1β and tumor necrosis factor-α (TNF-α) induced the expression of hsa-miR-150 in human gingival fibroblasts (HGF) (17). To clarify the mechanism whereby miRNA regulates the expression of inflammatory cytokines, we overexpressed hsa-miR-223 in HGF and examined the association between hsa-miR-223 and inflammatory cytokines.…”

RNA regulators of host immunity and pathogen adaptive responses in the oral cavity

“…Even so, one can already identify a sizeable shared core set of differentially regulated miRNAs among the current studies. From this core set of miRNAs, it is apparent that most of the reported miRNA responses in the periodontitis studies are quite similar to each other [57, 76, 80, 96, 117], while the same is true of the endodontic miRNA responses [16, 124]. However, when comparing the results of periodontitis vs. endodontic infections, nearly the entire overlapping set of miRNAs curiously exhibits an inverse relationship (Table 1).…”

“…There are currently only a handful of clinical studies that have examined the human miRNA responses to oral diseases [16, 57, 76, 80, 96, 117, 124] and nothing is yet known about the corresponding lncRNA responses. Despite this, some interesting patterns can be found among the available data suggesting the regulatory RNA responses triggered by periodontitis and endodontic infections are quite distinct.…”