Effects of lysophosphatidic acid on human periodontal ligament stem cells from teeth extracted from dental patients

Oral Disease and Atherosclerosis May Be Associated with Overlapping Metabolic Pathways

OBJECTIVES

Dental caries and periodontitis are among the most prevalent chronic diseases worldwide and have been associated with atherosclerotic cardiovascular diseases (ASCVD). This study aimed to determine (1) the independent associations between subclinical ASCVD markers (carotid intima media thickness [CIMT] and coronary artery calcification [CAC]) and quantitative indices of oral disease including the decayed, missing, and filled teeth (DMFT) index, gingivitis parameters, periodontal status, and number of teeth lost and (2) the extent to which metabolites altered in individuals with oral disease overlapped with those altered in individuals with ASCVD.

METHODS

We used data from 552 participants recruited through the Dental Strategies Concentrating on Risk Evaluation project. Oral examinations were conducted, and CIMT and CAC were measured. Multiple linear regression models were constructed with CIMT and CAC as dependent variables in the epidemiologic analysis. In the metabolomic analysis, logistic or linear regression was used to test 1,228 metabolites for association with each phenotype adjusted for age, sex, race, blood pressure, smoking, diabetes, cholesterol, high-sensitivity C-reactive protein, and interleukin-6.

RESULTS

None of the oral disease markers were significant predictors of ASCVD markers in the fully adjusted models. However, critical lipid and lipid-signaling pathway metabolites were significantly associated with gingivitis, periodontitis, and DMFT: the lysophospholipid pathway (odds ratio [OR] = 2.29, false discovery rate [FDR]-adjusted P = 0.038) and arachidonate with gingivitis (OR = 2.35, FDR-adjusted P = 0.015), the sphingolipid metabolism pathway with periodontitis (OR = 2.09, FDR-adjusted P = 0.029), and borderline associations between plasmalogen and lysophospholipid pathways and DMFT (P = 0.055). Further, the same metabolite from the sphingolipid metabolism pathway, sphingomyelin (d17:1/14:0, d16:1/15:0), was inversely associated with both CIMT (β = -0.14, FDR-adjusted P = 0.014) and gingivitis (OR = 0.04, FDR-adjusted P = 0.033).

CONCLUSIONS

The discovery of a common sphingomyelin metabolite in both disease processes is a novel finding suggesting that gingivitis and periodontitis may be associated with some overlapping metabolic pathways associated with ASCVD and indicating potential shared mechanisms among these diseases.

KNOWLEDGE TRANSFER STATEMENT

The same metabolites may be altered in atherosclerosis and oral disease. Specifically, a common sphingomyelin metabolite was inversely associated with gingivitis and carotid intima media thickness, a subclinical marker of atherosclerotic cardiovascular disease. These findings can provide valuable insights for future mechanistic studies to establish potential causal relationships, with the hope of influencing disease prevention and targeted early treatment.

Lysophosphatidic Acid/Polydopamine-Modified nHA Composite Scaffolds for Enhanced Osteogenesis via Upregulating the Wnt/Beta-Catenin Pathway

Guided bone regeneration (GBR) technology has been widely used for the regeneration of periodontal bone defects. However, the limited mechanical properties and bone regeneration potential of the currently available GBR membranes often limit their repair effectiveness. In this paper, serum-derived growth factor lysophosphatidic acid (LPA) nanoparticles and dopamine-decorative nanohydroxyapatite (pDA/nHA) particles were double-loaded into polylactic-glycolic acid/polycaprolactone (PLGA/PCL) scaffolds as an organic/inorganic biphase delivery system, namely, PP-pDA/nHA-LPA scaffolds. Physicochemical properties and osteogenic ability in vitro and in vivo were performed. Scanning electron microscopy and mechanical tests showed that the PP-pDA/nHA-LPA scaffolds had a 3D bionic scaffold structure with improved mechanical properties. In vitro cell experiments demonstrated that the PP-pDA/nHA-LPA scaffolds could significantly enhance the attachment, proliferation, osteogenic differentiation, and mineralization of MC3T3-E1 cells. In vivo, the PP-pDA/nHA-LPA scaffolds exhibited great cytocompatibility and cell recruitment ability in 2- and 4-week subcutaneous implantation experiments and significantly promoted bone regeneration in the periodontal defect scaffold implantation experiment. Moreover, LPA-loaded scaffolds were confirmed to enhance osteogenic activities by upregulating the expression of β-catenin and further activating the Wnt/β-catenin pathway. These results demonstrate that the biphase PP-pDA/nHA-LPA delivery system is a promising material for the GBR.

Triclosan inhibits the activation of human periodontal ligament fibroblasts induced by lipopolysaccharide from Porphyromonas gingivalis

Periodontitis is a highly prevalent, chronic, non-specific, and immunologically devastating disease of periodontal tissues, caused by microbial infection. This study aims to examine the efficacy and protective mechanism of triclosan (TCS), a bisphenolic, non-cationic component of oral care products, against periodontal inflammation induced by lipopolysaccharide purified from Porphyromonas gingivalis (LPS-PG). TCS markedly downregulated interleukin-6 (IL-6), IL-8, and IL-15 in human periodontal ligament fibroblasts (HPDLFs) treated with LPS-PG. By using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach, 318 differentially expressed proteins (161 upregulated and 157 downregulated) were identified in TCS-pretreated HPDLFs. TCS upregulated HSPA5 and HSP90B1 but downregulated HSPA2. Besides, TCS upregulated miR-548i in HPDLFs, which downregulated IL-15. These results indicate that TCS attenuates the activation of HPDLFs and downregulates the inflammatory cytokines through various mechanisms, thus highlighting its protective role in periodontal inflammation.