Evaluation of chemerin and its receptors, ChemR23 and CCRL2, in gingival tissues with healthy and periodontitis

Transcriptomic analysis identifies diagnostic genes in polycystic ovary syndrome and periodontitis

PURPOSE

To investigate underlying co-mechanisms of PCOS and periodontitis through transcriptomic approach.

METHODS

PCOS and periodontitis gene expression data were downloaded from the GEO database to identify differentially expressed genes. GO and KEGG pathway enrichment analysis and random forest algorithm were used to screen hub genes. GSEA analyzed the functions of hub genes. Correlations between hub genes and immune infiltration in two diseases were examined, constructing a TF-ceRNA regulatory network. Clinical samples were gathered from PCOS and periodontitis patients and RT-qPCR was performed to verify the connection.

RESULTS

There were 1661 DEGs in PCOS and 701 DEGs in periodontitis. 66 intersected genes were involved and were enriched in immune and inflammation-related biological pathways. 40 common genes were selected from the PPI network. RF algorithm demonstrated that ACSL5, NLRP12, CCRL2, and CEACAM3 were hub genes, and GSEA results revealed their close relationship with antigen processing and presentation, and chemokine signaling pathway. RT-qPCR results confirmed the upregulated gene expression in both PCOS and periodontitis.

CONCLUSION

The 4 hub genes ACSL5, NLRP12, CCRL2, and CEACAM3 may be diagnostic genes for PCOS and periodontitis. The created ceRNA network could provide a molecular basis for future studies on the association between PCOS and periodontitis.

A genome-wide association analysis: m6A-SNP related to the onset of oral ulcers

Oral ulcers are one of the most common inflammatory diseases on oral mucosa that have obvious impacts on patients. Studies have shown that N6-methyladenosine (m6A) RNA transcription modification may be involved in the development of various inflammatory responses, and whether the pathogenesis of oral ulcers is related to m6A is unclear. This study aims to identify how m6A-related single nucleotide polymorphisms (m6A-SNPs) may affect oral ulcers. The UKBB dataset containing 10,599,054 SNPs was obtained from the GWAS database using the keyword "oral ulcer" and compared with the M6AVar database containing 13,703 m6A-SNPs.With 7,490 m6A-SNPs associated with oral ulcers identified, HaploReg and RegulomeDB were used for further functional validation and differential gene analysis was performed using the GEO database dataset GSE37265. A total of 7490 m6A-SNPs were detected in this study, 11 of which were related to oral ulcers (p<5E-08), and all of these SNPs showed eQTL signals. The SNP rs11266744 (p=2.00E-27) may regulate the expression of the local gene CCRL2, thereby participating in the pathogenesis of oral ulcers. In summary, by analyzing genome-wide association studies, this study showed that m6A modification may be involved in the pathogenesis of oral ulcers and CCRL2 may be the targeted gene.

Chemerin contributes to inflammatory responses and suppresses osteogenic differentiation in chronic periodontitis

BACKGROUND

Chronic periodontitis (CP) is a common disease of oral cavity, and approximately 35% of adults suffered from CP. Therefore, its underlying mechanism needs to be explored for new therapeutic approaches. Chemerin as a multifunctional adipokine, is found to be highly expressed in the gingival crevicular fluid (GCF), gingival tissues and the plasma of periodontitis patients. Thus, we aimed to uncover the underlying mechanism of chemerin in CP.

METHODS

36 CP patients and 25 healthy volunteers were enrolled. Periodontal ligament stem cells (PDLSCs) were isolated from CP patients and healthy ones respectively. Then normal PDLSCs or PDLSCs-differentiated osteoblasts were treated with different doses of recombinant human chemerin.

RESULTS

Chemerin and inflammatory cytokines, including interleukin-1β, interleukin-6 and tumor necrosis factor-α, were higher in the GCF and serum of CP patients than healthy ones. Moreover, chemerin was positively correlated with these three inflammatory cytokines respectively in CP patients. PDLSCs isolated from CP patients had higher expressions of chemerin and these cytokines than the ones isolated from normal individuals. Furthermore, chemerin dose-dependently increased inflammatory responses and inhibited osteogenic differentiation of PDLSCs.

CONCLUSION

Chemerin accelerated inflammatory responses and suppressed osteogenic differentiation of PDLSCs, thus chemerin might sever as a therapeutic target of CP.

Chemerin/ChemR23 regulates cementoblast function and tooth resorption in mice via inflammatory factors

BACKGROUND

Periodontitis and orthodontic treatment can lead to inflammatory root resorption (IRR) through an unclear mechanism. Chemerin, a novel chemoattractant protein, is closely associated with inflammation, affects osteoblast and osteoclast differentiation, and may play a role in IRR. We aimed to explore possible roles of the chemerin/ChemR23 interaction in cementoblast function and IRR and reveal a new IRR therapeutic target.

METHODS

Cementoblast function-related gene and protein expression in the immortalized murine cementoblast cell line OCCM-30 after treatment with chemerin and siChemR23 was examined by qRT-PCR and Western blotting.The roles of the MAPK and PI3K-Akt signaling pathways were studied using specific inhibitors. Cementoblast cytokine production under different treatment conditions was measured by ELISA and qRT-PCR. Additionally, we modeled IRR in wild-type and chemerin-overexpressing mice and injected transgenic mice with anti-ChemR23 antibody to block ChemR23. We then calculated the root resorption volume and examined periodontal tissue cathepsin K, Runx2, TNF-α, and IL-6 expression.

RESULT

Chemerin suppressed cementoblast differentiation and mineralization and exerted a proinflammatory effect on cementoblasts. These effects were partially reversed by siChemR23 and reversed to different extents by p38, Erk1/2 and PI3K-Akt pathway inhibition, suggesting p38, Erk1/2 and PI3K-Akt pathways as signaling pathways downstream of chemerin/ChemR23. In vivo, chemerin overexpression worsened IRR. Moreover, chemerin expression was positively correlated with TNF-α, IL-6, and cathepsin K expression and negatively correlated with Runx2 expression. ChemR23 downregulation reversed these effects.

CONCLUSION

Chemerin/ChemR23 induced TNF-α and IL-6 expression dependent on Erk1/2, p38 MAPK and PI3K-Akt signaling pathway activation, thereby regulating cementoblast function and affecting IRR. This article is protected by copyright. All rights reserved.

Evaluation of adipokines and inflammatory mediator expression levels in patients with periodontitis and peri-implantitis: a cross-sectional study

OBJECTIVES

The aim of this study was to analyze the mRNA and protein expression of adiponectin, leptin, visfatin, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 levels in periodontitis and peri-implantitis sites in systemically healthy individuals and to investigate the influence of the presence of current periodontitis on their expression levels in peri-implantitis sites.

MATERIALS AND METHODS

Soft tissue biopsy samples were collected from 60 systemically healthy patients [15 periodontally healthy patients (group I), 16 patients with periodontitis (group II), 15 patients with peri-implantitis (group III), and 14 patients with peri-implantitis and periodontitis (group IV)]; mRNA expression levels of adiponectin, leptin, visfatin, TNF-α, and IL-6 were measured by quantitative real-time PCR; and their protein levels were assessed by immunohistochemistry.

RESULTS

The mRNA expression levels of all biomarkers were significantly higher for group II compared to group I, while significantly higher levels of leptin, TNF-α, and IL-6 were observed in group III in comparison with group I. Group II exhibited significantly higher mRNA expression of adiponectin and TNF-α than group III. Group IV showed significantly higher expression levels of adiponectin, leptin, TNF-α, and IL-6 compared to group III. Regarding the expression of protein levels, which was estimated through quantification of the histoscore, both groups II and III presented higher H-scores than group I for all biomarkers except leptin.

CONCLUSIONS

The presence of current periodontitis may enhance expression levels of adiponectin, leptin, TNF-α, and IL-6 in peri-implant soft tissue.

CLINICAL RELEVANCE

The presence of periodontitis is an important risk factor for the severity of peri-implant inflammation as well as the onset of peri-implantitis.

Adipokines and Inflammation: Focus on Cardiovascular Diseases

It is well established that adipose tissue, apart from its energy storage function, acts as an endocrine organ that produces and secretes a number of bioactive substances, including hormones commonly known as adipokines. Obesity is a major risk factor for the development of cardiovascular diseases, mainly due to a low grade of inflammation and the excessive fat accumulation produced in this state. The adipose tissue dysfunction in obesity leads to an aberrant release of adipokines, some of them with direct cardiovascular and inflammatory regulatory functions. Inflammation is a common link between obesity and cardiovascular diseases, so this review will summarise the role of the main adipokines implicated in the regulation of the inflammatory processes occurring under the scenario of cardiovascular diseases.