The pro-apoptotic and pro-inflammatory effects of calprotectin on human periodontal ligament cells

Yunfei Zheng; Jianxia Hou; Lei Peng; Xin Zhang; Lingfei Jia; Xian'e Wang; Shicheng Wei; Huanxin Meng

doi:10.1371/journal.pone.0110421

The pro-apoptotic and pro-inflammatory effects of calprotectin on human periodontal ligament cells

PLoS One. 2014 Oct 22;9(10):e110421. doi: 10.1371/journal.pone.0110421. eCollection 2014.

Authors

Yunfei Zheng¹, Jianxia Hou², Lei Peng³, Xin Zhang⁴, Lingfei Jia⁵, Xian'e Wang², Shicheng Wei⁶, Huanxin Meng²

Affiliations

¹ Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, P.R. China; Department of Periodontology, Peking University School and Hospital of Stomatology, Beijing, P.R. China.
² Department of Periodontology, Peking University School and Hospital of Stomatology, Beijing, P.R. China.
³ Department of Stomatology, Beijing Friendship Hospital, Capital Medical University, Beijing, P.R. China.
⁴ Department of Stomatology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, P.R. China.
⁵ Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, P.R. China; Laboratory of Molecular Biology, Peking University School and Hospital of Stomatology, Beijing, China.
⁶ Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, P.R. China.

Abstract

Calprotectin, a heterodimer of S100A8 and S100A9 subunits, is associated with inflammatory disorders such as rheumatoid arthritis and cystic fibrosis. Although calprotectin levels are increased significantly in the gingival crevicular fluid (GCF) of periodontitis patients, its effects on periodontal ligament cells (PDLCs) remain largely unknown. The aim of this study was to evaluate calprotectin levels in the GCF of generalized aggressive periodontitis (AgP) patients and to investigate the effects of recombinant human calprotectin (rhS100A8/A9) and its subunits (rhS100A8 and rhS100A9) in PDLCs. Both the concentration and amount of crevicular calprotectin were significantly higher in the AgP group compared with healthy controls. In addition, the GCF calprotectin levels were correlated positively with clinical periodontal parameters including bleeding index, probing depth, and clinical attachment loss. rhS100A8/A9 promoted cell apoptosis, whereas rhS100A8 and rhS100A9 individually exerted little effect on apoptosis in PDLCs. rhS100A9 and rhS100A8/A9 increased the activation of nuclear factor-κB (NF-κB) by promoting the nuclear translocation of p65 in PDLCs, subsequently inducing expression of the pro-inflammatory cytokines IL-6, IL-8, TNFα, and COX2. Treatment with an NF-κB inhibitor partially reversed the rhS100A9- and rhS100A8/A9-induced upregulation of the pro-inflammatory cytokines. rhS100A9, and not rhS100A8, was mainly responsible for the pro-inflammatory role of calprotectin. Collectively, our results suggest that calprotectin promotes apoptosis and the inflammatory response in PDLCs via rhS100A9. These findings might help identify novel treatments for periodontitis.

Publication types

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

MeSH terms

Adult
Aggressive Periodontitis / genetics
Aggressive Periodontitis / metabolism*
Aggressive Periodontitis / pathology
Apoptosis / drug effects
Calgranulin A / biosynthesis
Calgranulin A / genetics
Calgranulin B / biosynthesis
Calgranulin B / genetics
Calgranulin B / pharmacology*
Case-Control Studies
Connective Tissue Cells / cytology
Connective Tissue Cells / drug effects*
Connective Tissue Cells / metabolism
Cyclooxygenase 2 / genetics
Cyclooxygenase 2 / metabolism
Female
Gene Expression
Gingival Crevicular Fluid / chemistry
Humans
Interleukin-6 / genetics
Interleukin-6 / metabolism
Interleukin-8 / genetics
Interleukin-8 / metabolism
Leukocyte L1 Antigen Complex / biosynthesis
Leukocyte L1 Antigen Complex / genetics
Leukocyte L1 Antigen Complex / pharmacology*
Male
NF-kappa B / antagonists & inhibitors
NF-kappa B / genetics
NF-kappa B / metabolism
Periodontal Ligament / cytology
Periodontal Ligament / drug effects*
Periodontal Ligament / metabolism
Primary Cell Culture
Proline / analogs & derivatives
Proline / pharmacology
Recombinant Proteins / biosynthesis
Recombinant Proteins / genetics
Recombinant Proteins / pharmacology
Thiocarbamates / pharmacology
Tumor Necrosis Factor-alpha / genetics
Tumor Necrosis Factor-alpha / metabolism

Substances

Calgranulin A
Calgranulin B
IL6 protein, human
Interleukin-6
Interleukin-8
Leukocyte L1 Antigen Complex
NF-kappa B
Recombinant Proteins
Thiocarbamates
Tumor Necrosis Factor-alpha
prolinedithiocarbamate
Proline
Cyclooxygenase 2
PTGS2 protein, human

Grants and funding

This work was supported by the National Natural Science Foundation of China (30271411, 30471882, 30973319), and HX Meng received the funding for this work. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.