Diabetes is an important risk factor for periodontitis, and circular RNA (circRNA) may play an important role in aggravating inflammation and accelerating disease progression by regulating miRNA/mRNA. This study aimed to investigate the role and mechanism of the hsa_circ_0084054/miR-508-3p/PTEN axis in the progression of periodontitis with diabetes. First, circRNA sequencing was used to screen the differentially expressed circRNAs of periodontal ligament cells (PDLCs) treated with high glucose and/or Porphyromonas gingivalis lipopolysaccharide (LPS) in vitro, and the overtly differentially expressed hsa_circ_0084054 was selected and was also verified in periodontal ligament (PDL) tissue from periodontitis patients with diabetes. Then, its ring structure was tested by Sanger sequencing, RNase R, and actinomycin D assays. The bioinformatics analysis, dual luciferase reporter assay, and RIP assay were used to explore the interaction of hsa_circ_0084054/miR-508-3p/PTEN axis, whose effects on inflammation, oxidative stress, and apoptosis of PDLCs were evaluated through the measurement of inflammatory factors, reactive oxygen species (ROS), total superoxide dismutase (SOD), malondialdehyde (MDA), and Annexin V/PI assay. By high-throughput sequencing, it was found that hsa_circ_0084054 was significantly increased in HG + LPS group compared with control group and LPS group, which was also verified in periodontal ligament (PDL) tissue from periodontitis patients with diabetes. Silencing hsa_circ_0084054 in PDLCs decreased the expression of inflammatory factors (IL-1β, IL-6, TNF-α), the levels of ROS and MDA, and the proportion of apoptotic cells; conversely, SOD activity was enhanced. In addition, we found that hsa_circ_0084054 could up-regulate the expression of PTEN through sponge miR-508-3p to inhibit AKT phosphorylation, finally trigger the aggravation of oxidative stress and inflammation in periodontitis patients with diabetes. hsa_circ_0084054 can aggravate inflammation and promote the progression of periodontitis with diabetes by regulating miR-508-3p/PTEN signaling axis, which may serve as a new target for the intervention of periodontitis with diabetes.
Read full abstract