Nicotine regulates autophagy of human periodontal ligament cells through α7 nAchR that promotes secretion of inflammatory factors IL-1β and IL-8

Yang Du; Kuan Yang; Zhifei Zhou; Lizheng Wu; Lulu Wang; Yujiang Chen; Xin Ge; Xiaojing Wang

doi:10.1186/s12903-021-01894-5

Nicotine regulates autophagy of human periodontal ligament cells through α7 nAchR that promotes secretion of inflammatory factors IL-1β and IL-8

BMC Oral Health. 2021 Nov 3;21(1):560. doi: 10.1186/s12903-021-01894-5.

Authors

Yang Du¹, Kuan Yang², Zhifei Zhou³, Lizheng Wu⁴, Lulu Wang¹, Yujiang Chen¹, Xin Ge¹, Xiaojing Wang⁵

Affiliations

¹ State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Pediatric Dentistry, School of Stomatology, The Fourth Military Medical University, No.145 West Changle Road, Xi'an, 710032, Shaanxi, China.
² Department of Orthodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.
³ Department of Stomatology, The General Hospital of Tibetan Military Region, Lhasa, China.
⁴ Department of Stomatology, Characteristic Medical Center of People's Armed Police Force, Tianjin, China.
⁵ State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Pediatric Dentistry, School of Stomatology, The Fourth Military Medical University, No.145 West Changle Road, Xi'an, 710032, Shaanxi, China. wxjingpd@hotmail.com.

Abstract

Background: Nicotine is an important risk factor and the main toxic component associated with periodontitis. However, the mechanism of nicotine induced periodontitis is not clear. To investigated the mechanism through which nicotine regulates autophagy of human periodontal ligament cells (hPDLCs) through the alpha7 nicotinic acetylcholine receptor (α7 nAChR) and how autophagy further regulates the release of IL-1β and IL-8 secretion in hPDLCs.

Methods: HPDLCs were obtained from root of extracted teeth and pre-incubated in alpha-bungarotoxin (α-BTX) or 3-Methyladenine (3-MA), followed by culturing in nicotine. We used a variety of experimental detection techniques including western blotting, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), transmission electron microscopy (TEM) and RT-qPCR to assess the expression of the LC3 protein, autolysosome, and release of IL-1β and IL-8 from hPDLCs.

Results: Western blots, immunofluorescence and TEM results found that the nicotine significantly increased the autophagy expression in hPDLCs that was time and concentration dependent and reversed by α-BTX treatment (p < 0.05). RT-qPCR and ELISA results revealed a noticeable rise in the release of inflammatory factors IL-1β and IL-8 from hPDLCs in response to nicotine. RT-qPCR and ELISA results showed that nicotine can significantly up-regulate the release of inflammatory factors IL-1β and IL-8 in hPDLCs, and this effect can be inhibited by 3-MA (p < 0.05).

Conclusions: Nicotine regulated autophagy of hPDLCs through α7 nAChR and in turn the regulation of the release of inflammatory factors 1L-1β and 1L-8 by hPDLCs.

Keywords: Autophagy; Nicotine; Periodontitis; α7 nAchR.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Autophagy
Cells, Cultured
Humans
Interleukin-8* / genetics
Nicotine* / toxicity
Periodontal Ligament

Substances

Interleukin-8
Nicotine