Circ_0036490 and DKK1 competitively bind miR-29a to promote lipopolysaccharides-induced human gingival fibroblasts injury

Abstract

MicroRNA (miRNA) plays a regulatory role in periodontitis. This study aimed to explore whether miR-29a could affect lipopolysaccharides (LPSs)-induced injury in human gingival fibroblasts (HGFs) through the competitive endogenous RNAs (ceRNA) mechanism. Periodontal ligament (PDL) tissues and HGFs were derived from patients with periodontitis and healthy volunteers. Periodontitis cell model was established by treating HGFs with LPS. Expression levels of circ_0036490, miR-29a, and DKK1 were evaluated by the reverse transcription quantitative real-time PCR (RT-qPCR) method. Western blotting assay was performed to assess protein expression levels of pyroptosis-related proteins and Wnt signalling related proteins. Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. Concentration of lactate dehydrogenase (LDH), interleukin (IL)-1β, and IL-18 were determined by Enzyme-linked immunosorbent assay (ELISA). Pyroptosis rate were determined by flow cytometry assay to evaluate pyroptosis. The interaction between miR-29a and circ_0036490 or DKK1 was verified by dual-luciferase reporter and RNA pull-down assays. MiR-29a expression was lower in PDL tissues of patients with periodontitis than that in healthy group; likewise, miR-29a was also downregulated in LPS-treated HGFs. Overexpression of miR-29a increased cell viability and decreased pyroptosis of HGFs induced by LPS while inhibition of miR-29a exerted the opposite role. MiR-29a binds to circ_0036490 and elevation of circ_0036490 contributed to dysfuntion of LPS-treated HGFs and reversed the protection function of elevated miR-29a. In addition, miR-29a targets DKK1. Overexpression of DKK1 abrogated the effects of overexpressed miR-29a on cell vaibility, pyroptosis, and protein levels of Wnt signalling pathway of LPS-treated HGFs. Circ_0036490 and DKK1 competitively bind miR-29a to promote LPS-induced HGF injury in vitro. Wnt pathway inactivated by LPS was activated by miR-29a. Thence, miR-29a may be a promising target for periodontitis.

Keywords:

• Periodontitis
• human gingival fibroblasts
• pyroptosis
• circ_0036490
• miR-29a
• DKK1

Authors’ contributions

All authors participated in the design, interpretation of the studies and analysis of the data and review of the manuscript. Y.W. drafted the work and revised it critically for important intellectual content; B.L., D.D., H.Z., and M.L. were responsible for the acquisition and analysis; H.A., Y.X., and W.H. were responsible for the interpretation of data for the work; L.Z. and L.L. made substantial contributions to the conception or design of the work.

Disclosure statement of competing interest

No conflict of interest exits in the submission of this manuscript, and manuscript is approved by all authors for publication.

The regulatory mechanism study of Bushen Huoxue Guchi therapy on alveolar bone remodelling of orthodontic tooth with chronic periodontitis based on the miR-29a mediated Dkk-1/Wnt-TNF-α interactive crosstalk (NSFC 81973684).

From the “central-peripheral” holistic perspective to explore the regulatory mechanism of “replenishing qi and opening orifices for reducing phlegm” on Aβ clearance across the blood-brain barrier in Alzheimer’s disease (NSFC82174345).

The study on PDLSCs combined with nanofiber composite scaffold with gradation in cytokines concentration to engineer PDL–bone interface (NSFC 31670992).

The imaging study of syndrome essence and syndrome element evolution in acute ischaemic stroke during over-time window treatment based on DKI (NSFC82074303).

Data availability statement

The datasets used and analysed during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

This work was supported by National Natural Science Foundation of China (Grant No. 81973684, 82174345, 31670992, 82074303).