Therapeutic Effect of a Novel M1 Macrophage-Targeted Nanodrug in Chronic Periodontitis Mice

Chronic periodontitis is a chronic, progressive, and destructive disease. Especially, the large accumulation of advanced glycation end products (AGEs) in a diseased body will aggravate the periodontal tissue damage, and AGEs induce M1 macrophages. In this project, the novel nanodrugs, glucose-PEG-PLGA@MCC950 (GLU@MCC), are designed to achieve active targeting with the help of glucose transporter 1 (GLUT1) which is highly expressed in M1 macrophages induced by AGEs. Then, the nanodrugs release MCC950, which is a kind of NLRP3 inhibitor. These nanodrugs not only can improve the water solubility of MCC950 but also exhibit superior characteristics, such as small size, stability, innocuity, etc. In vivo experiments showed that GLU@MCC could reduce periodontal tissue damage and inhibit cell apoptosis in periodontitis model mice. In vitro experiments verified that its mechanism of action might be closely related to the inhibition of the NLRP3 inflammatory factor in M1 macrophages. GLU@MCC could effectively reduce the damage to H400 cells caused by AGEs, decrease the expression of NLRP3, and also obviously reduce the M1-type macrophage pro-inflammatory factors such as IL-18, IL-1β, caspase-1, and TNF-α. Meanwhile, the expression of anti-inflammatory factor Arg-1 in the M2 macrophage was increased. In brief, GLU@MCC would inhibit the expression of inflammatory factor NLRP3 and exert antiperiodontal tissue damage in chronic periodontitis via GLUT1 in the M1 macrophage as the gating target. This study provides a novel nanodrug for chronic periodontitis treatment.

Evaluation of CD44 antigen in type 2 diabetic patients with periodontitis: An immunohistochemical study

BACKGROUND

Type 2 diabetes mellitus (DM) is a known systemic risk factor for periodontitis. An increased expression of CD44 has been suggested in type 2 diabetics and periodontitis patients.

OBJECTIVES

The present study aimed to assess the expression of CD44 antigen in patients with chronic periodontitis (CP) and type 2 DM in a South Indian urban population. Additionally, the relationships between the expression of CD44 antigen in gingival tissues, periodontal clinical parameters, and the random blood sugar (RBS) and glycated hemoglobin (HbA1c) levels were assessed.

MATERIAL AND METHODS

A total of 63 subjects were divided into 3 groups: systemically and periodontally healthy controls (group H); CP patients, otherwise healthy (group CP); and CP patients with type 2 DM (group CP+DM). Periodontal parameters were recorded for all groups, and additionally the RBS and HbA1c levels for group CP+DM. Gingival tissue samples were obtained and subjected to immunohistochemical analysis for CD44.

RESULTS

The expression of CD44 was significantly higher in the diseased groups. Epithelial CD44 expression was significantly stronger in group CP+DM as compared to groups CP and H (p < 0.001), whereas connective tissue CD44 expression was similar in groups CP and CP+DM (p = 0.657). Furthermore, an inverse relationship was observed between blood glucose parameters and CD44 expression in the epithelium and connective tissue.

CONCLUSIONS

The expression of CD44 increased with the severity of periodontal disease. Additionally, glycemic control in patients with CP and type 2 DM had an impact on CD44 expression. Our findings indicate a possible destructive role of CD44 in the pathogenesis of periodontal diseases in individuals with type 2 DM.

Biological marker for the establishment of periodontal disease: cross-sectional study in the gingival tissue

BACKGROUND

The present study investigated the expression of COX-2, EMMPRIN, HIF-1α, and GLUT-1 in the gingival tissue to verify if there is a correlation between the immunoexpression of these proteins and the changes caused by the inflamed infiltrate present in the gingival tissues.

MATERIAL AND METHODS

A morphological analysis of epithelial changes (hyperplasia, exocytosis, spongiosis, and hydropic degeneration) was performed, as well as a semiquantitative analysis of the immunoexpression of COX-2, EMMPRIN, HIF-1α, and GLUT-1 in the epithelium and connective tissue of 60 specimens of gingival tissue.

RESULTS

Epithelial immunoexpression to COX-2 was observed in three cases, while EMMPRIN, HIF-1α, and GLUT-1 were strongly expressed in the basal layer of the epithelium and gradually decreased until the upper layers. In the connective tissue, COX-2 immunoexpression showed a statistically significant association (p < 0.001) with the gingival inflammatory infiltrate. In connective tissue, EMMPRIN and HIF-1α exhibited intense immunopositivity, while GLUT-1 was negative in most cases.

CONCLUSION

COX-2 expression may constitute a biological marker of gingival tissues since its epithelial immunoexpression may indicate a greater propensity for the establishment of periodontal disease.

Effect of non-surgical periodontal therapy on CD14 + CD16+ monocyte counts in peripheral blood samples: a clinical interventional study

Monocytes and their macrophage progeny are thought to be involved in tissue and alveolar bone destruction in periodontal disease. It has been documented that the proportion of (CD14 + CD16+) non-classical monocytes in the blood are elevated in chronic periodontitis;A total of 20 chronic generalized periodontitis patients who were otherwise healthy, were recruited for this study. At baseline and 3 weeks after non-surgical periodontal treatment, peripheral blood was obtained to assess the levels of C-reactive protein (CRP) and the proportion of monocyte subsets. Monocyte subsets were assessed using flow cytometry;The mean percentage of CD14 + CD16+ non-classical monocytes in the peripheral blood sample at baseline was 13.95 + 2.09, that reduced to 8.94 + 1.23 3 weeks after non-surgical treatment. A distinct significant reduction in the percentage of non-classical monocytes and a concomitant increase in classical monocytes were observed following periodontal treatment compared to baseline. There was a significant reduction in the all the periodontal parameters and CRP levels 3 weeks post non-surgical periodontal treatment. A positive correlation between CRP and percentage of non-classical monocytes was also observed; Periodontal treatment potentially modulates the host response effectively.

Sirtuin6 and Lipoxin A4 levels are decreased in severe periodontitis

OBJECTIVE

Sirtuin6 plays an important role in the regulation of inflammation, homeostasis, and apoptosis, and it has anti-inflammatory effects on several diseases. Lipoxin A4 is a pro-resolving lipid mediator of inflammation and inhibits hypoxia-induced apoptosis and oxidative stress. Considering that Lipoxin A4 and Sirtuin6 have protective effects on inflammatory diseases, the aim of this study is to determine the possible roles of these molecules on periodontitis inflammation in saliva and serum and to reveal the relationship of these data with clinical periodontal parameters.

MATERIAL AND METHODS

A total of 20 stage III/grade B periodontitis and 20 periodontally healthy subjects were included in this cross-sectional study (all never smokers and systemically healthy). Clinical periodontal parameters (plaque index, probing pocket depth, bleeding on probing, clinical attachment loss) were recorded. Saliva and serum levels of Sirtuin6 and Lipoxin A4 were analyzed by enzyme-linked immunosorbent assay.

RESULTS

Serum Sirtuin6 and saliva Lipoxin A4 levels were significantly lower in the periodontitis group than the control group (respectively, p = 0.0098, p = 0.0008). There were negative correlations between all periodontal clinical parameters and saliva Lipoxin A4 level (p < 0.05) and between probing pocket depth, clinical attachment loss, and serum and saliva Sirtuin6 levels (respectively, r =  - 0.465 and r =  - 0.473, p < 0.05).

CONCLUSIONS

Decreased levels of serum Sirtuin6 and saliva Lipoxin A4 in periodontitis patients and their correlation with clinical periodontal parameters suggest that serum Sirtuin6 and saliva Lipoxin A4 may be related with periodontal inflammation.

CLINICAL RELEVANCE

Scientific rationale for the study: Sirtuin6 is one of seven members of the family of NAD + dependent protein that played an important role in the regulation of inflammation, energy metabolism, homeostasis, and apoptosis. Sirtuin6 is associated with the pathogenesis of several diseases. Lipoxin A4 is a lipid mediator that inhibits hypoxia-induced apoptosis and oxidative stress, and it has an active role in the resolution of periodontal inflammation. No studies that investigated the potential role Sirtuin6 and its relationship with inflammation resolution and apoptosis mechanisms in severe periodontitis patients.

PRINCIPAL FINDINGS

the serum Sirtuin6 and saliva Lipoxin A4 levels were significantly lower and negatively correlated with clinical periodontal parameters in the patients with periodontitis than the healthy controls.

PRACTICAL IMPLICATIONS

this study shows that serum Sirtuin6 and saliva Lipoxin A4 may be candidate biomarkers related with periodontal inflammation and estimating to periodontal status.

CLINICAL TRIAL REGISTRATION

NCT05417061.

[Effect of ultrasonic curettage combined with sodium hyaluronate gel on chronic periodontitis and its effect on inflammatory factors hs-CRP, MCP-1 and MMP-13 in gingival crevicular fluid]

PURPOSE

To investigate the effect of ultrasonic curettage combined with sodium hyaluronate gel in the treatment of chronic periodontitis (CP) and the effect on inflammatory factor hypersensitive C-reactive protein (hs-CRP), monocyte chemotactic protein 1 (MCP-1) and matrix metalloproteinase 13 (MMP-13) in gingival crevicular fluid.

METHODS

A total of 102 patients with CP from October 2021 to October 2022 were selected, divided into experimental group (n=51) and control group (n=51) by random number table method. The control group received ultrasonic subgingival curetage, and the experimental group received sodium hyaluronate gel adjuvant therapy on the basis of the control group. The periodontal rehabilitation indexes, clinical efficacy and the changes of gingival crevicular fluid hs-CRP, MCP-1 and MMP-13 were compared between the two groups. The periodontal pathogens, bone metabolism indexes and the occurrence of adverse events during treatment were compared between the two groups. The data were statistically analyzed using SPSS 22.0 software package.

RESULTS

After treatment, the sulcus bleeding index (SBI), gingival index (GI), plaque index (PLI), periodontal pocket depth (PD) and attachment level (AL) of the two groups were significantly lower than before treatment (P＜0.05), and even significantly lower(P＜0.05) in the experimental group. Total effective rate of the experimental group was significantly higher than that of the control group(P＜0.05). hs-CRP, MCP-1 and MMP-13 in both groups after treatment were significantly lower than before treatment(P＜0.05), and hs-CRP, MCP-1 and MMP-13 in the experimental group after treatment were significantly lower than those in the control group(P＜0.05). The detection rates of Porphyromonas gingivalis, Forsetanella and Treponema dentalis were significantly lower in both groups after treatment than before treatment (P＜0.05), and the detection rates of the above indexes in the experimental group after treatment were significantly lower than those in the control group(P＜0.05). After treatment, the C-terminal peptide(CTX) of type Ⅰ collagen was significantly lower than that before treatment, and bone gla protein(BGP) was significantly higher than that before treatment(P＜0.05). The CTX and BGP of the experimental group were significantly lower than that of the control group and significantly higher than that of the control group(P＜0.05). There was no significant difference in the incidence of total adverse reactions between the two groups(P＞0.05). CONCLUSIONS：Ultrasonic curettage combined with sodium hyaluronate gel in the treatment of CP can promote periodontal tissue rehabilitation, enhance short-term efficacy, inhibit synthesis of inflammatory factors in gingival crevicular fluid, kill periodontal pathogens, regulate bone metabolism, and is safe and reliable.

Chronic periodontitis induces the proliferation of pancreatic β-cells to cause hyperinsulinemia in a rat model

BACKGROUND AND OBJECTIVE

The purpose of this study was to determine if chronic periodontitis (CP) may induce hyperinsulinemia and may have the effect of on pancreatic β-cell proliferation in a rat model.

MATERIALS AND METHODS

Twelve male Sprague-Dawley rats were divided into two groups: the CP group and the control group (Con group). The following contents were evaluated: pathological changes in periodontal soft and hard tissues; serum lipopolysaccharide (LPS) level, serum fasting insulin (FINS) level, fasting blood glucose (FBG) level, and homeostasis model assessment (HOMA) β (HOMA-β) index; histopathological examination of islets; immunohistochemistry of insulin and p-Smad2 expression in islets; immunofluorescence of changes in the relative number of β-cells and the number of Ki67-positive β-cells. Western blotting was used to analyze p-Smad2/Smad2 levels. Results were analyzed by two independent samples t tests.

RESULTS

Increased serum LPS level, FINS level, and HOMA-β index were observed in the rats of the CP group; FBG level did not change significantly; histological assessments showed an enlarged islet area, increased insulin content, relatively increased β-cells, increased Ki67-positive β-cells, and decreased p-Smad2 expression in islets in the rats of the CP group.

CONCLUSION

Our study results link CP-induced hyperinsulinemia with changes in islets, such as islet hyperplasia and compensatory β-cell proliferation, by using a CP rat model.

Influence of type 2 diabetes on immunohistochemical detection of TRAF6, cFos and NFATC1 in the gingiva in cases of chronic periodontitis

Type 2 diabetes (T2D) and chronic periodontitis (CP) are common diseases worldwide. Although T2D increases the severity of CP and alveolar bone loss, the mechanism of this is not well understood. We investigated using immunohistochemistry the expression of three osteoclast proteins, TRAF6, cFos and NFATc1, in gingival tissues. Gingival tissues were obtained from three groups: HC group, healthy controls; CP group, patients with CP; T2D + CP group, patients with both T2D and CP. Strong immunostaining for TRAF6, cFos and NFATc1 was observed in the gingival epithelium as well as in inflammatory cells in the CP and T2D + CP groups. Immunostaining was most intense in the T2D + CP group. We found strong up-regulation of TRAF6, cFos and NFATC1 in gingiva tissue of subjects with both T2D and CP, which corroborates our hypothesis that T2D potentiates osteoclastogenesis in CP.

Gingival crevicular fluid periodontal ligament-associated protein-1, sclerostin, and tumor necrosis factor-alpha levels in periodontitis

BACKGROUND

In periodontitis, the equilibrium between bone formation and resorption skews in favor of bone loss. Periodontal ligament-associated protein-1 (PLAP-1) and sclerostin play a significant role in the suppression of bone formation. Tumor necrosis factor-alpha (TNF-α) is a central proinflammatory cytokine related to periodontal bone loss. This study aims to assess gingival crevicular fluid (GCF) PLAP-1, sclerostin, and TNF-α levels in individuals with periodontal disease.

METHODS

Seventy-one individuals diagnosed with generalized stage III grade C periodontitis (n = 23), gingivitis (n = 24), and periodontal health (n = 24) were included in the study. Full-mouth clinical periodontal measurements were performed. PLAP-1, sclerostin, and TNF-α total amounts in GCF were quantified by ELISA. Nonparametric methods were used for the data analyses.

RESULTS

Periodontitis group exhibited significantly higher GCF PLAP-1, sclerostin and TNF-α levels compared with gingivitis and periodontally healthy groups (p < 0.05). GCF PLAP-1 and TNF-α levels of gingivitis group were higher than healthy controls (p < 0.05) whereas GCF sclerostin levels were similar in two groups (p > 0.05). Significant positive correlations were found between GCF PLAP-1, sclerostin and TNF-α levels and all clinical parameters (p < 0.01).

CONCLUSIONS

To our knowledge, this is the first study showing GCF PLAP-1 levels in periodontal health and disease. Increased GCF PLAP-1 and sclerostin levels and their correlations with TNF-α in periodontitis imply that those molecules might be involved in the pathogenesis of periodontal disease. Further studies in larger mixed cohorts are needed to enlighten the possible role of PLAP-1 and sclerostin in periodontal bone loss.

Salivary levels of NLRC4 inflammasome in different periodontal clinical status

OBJECTIVE

Nucleotide-binding and oligomerization domain (NOD)-like receptor family CARD domain-containing protein 4 (NLRC4) has a critical role in the regulation of interleukin-1β (IL-1β), an important cytokine in the pathogenesis of the periodontal diseases. In this study, we aimed to evaluate levels of salivary NLRC4 inflammasomes in different periodontal clinical statuses.

METHODS

The individuals with 20 periodontally healthy (healthy), 20 gingivitis, and 20 periodontitis were periodontally examined. Saliva samples were collected, after the clinical measurements (plaque index, gingival index, gingival bleeding index, probing depth, and clinical attachment level). The levels of salivary NLRC4, IL-1β, and interleukin 10 (IL-10) were examined by enzyme-linked immunosorbent assay.

RESULTS

The results demonstrated that levels of salivary NLRC4 (p < 0.01), and IL-1β (p < 0.001) were significantly higher in gingivitis and periodontitis than in the healthy group. No significant difference was salivary IL-10 levels between the groups (p > 0.05). Positive significant correlations among NLRC4 and IL-1β salivary levels and clinical parameters were detected (p < 0.05).

CONCLUSION

The findings of this study suggest that the NLRC4 is elevated in periodontal disease. Larger randomized controlled clinical studies are needed to use salivary NLRC4 levels as a potential marker for detecting the presence and/or severity of the periodontal disease.

Role of ubiquitin-specific protease 5 in the inflammatory response of chronic periodontitis

BACKGROUND

The systemic inflammatory response caused by chronic periodontitis is a risk factor for multiple diseases. Ubiquitin-specific protease 5 (USP5) is a kind of deubiquitinase which mainly responsible for dissociating unanchored polyubiquitin. However, the functions of USP5 in chronic periodontitis have not been reported.

METHODS

Chronic periodontitis patients were recruited, and their periodontal samples were collected. The levels of USP5, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in gingival crevicular fluid were evaluated by ELISA. The expression of USP5, TNF-α, IL-6, and IL-1β in human periodontal ligament stem cells (PDLSCs) was estimated by qRT-PCR assay. The activation of STAT3 signaling was examined by Western blot.

RESULTS

USP5 was upregulated in the gingival crevicular fluid and gingival tissues of chronic periodontitis patients. USP5 expression was positively correlated with the expression of proinflammatory factors. USP5 knockdown and deubiquitinase inhibitor inhibited LPS-induced inflammatory responses in PDLSCs. Suppressing USP5 inhibited STAT3 signaling in PDLSCs.

CONCLUSION

Suppression deubiquitinase USP5 inhibits the inflammatory response of chronic periodontitis by suppressing STAT3 signaling.

Oxidative stress in human gingival fibroblasts from periodontitis versus healthy counterparts

OBJECTIVE

Elevated p53 promotes oxidative stress and production of pro-inflammatory cytokines in liposaccharide (LPS)-treated healthy human gingival fibroblasts (HGFs). This study compared oxidative stress, production of inflammatory cytokines, and p53 expression in HGFs from patients with chronic periodontitis (CP) and healthy subjects in vitro upon LPS from Porphyromonas gingivalis challenge.

METHODS

Human gingival fibroblasts were isolated from 6 biopsies-3 from healthy donors and 3 from diseased area in CP (Grade B, Stage III). HGFs were cultured with or without 1 μg/ml 24 h LPS. Oxidative stress was assessed by analyzing the level of reactive oxygen species (ROS). Mitochondrial membrane potential and respiration were determined by immunofluorescence and respirometry, respectively. Tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β were determined by enzyme-linked immunosorbent assay. P53 expression was monitored by Western blot and immunofluorescence.

RESULTS

Human gingival fibroblasts from CP exhibited increased levels of mitochondrial p53, enhanced ROS production, decreased mitochondrial membrane potential, increased mitochondrial oxygen consumption, and increased secretion of TNF-α, IL-6, and IL-1β, as compared to HGFs from healthy donors. Moreover, LPS exacerbated these changes.

CONCLUSION

Human gingival fibroblasts from CP exhibited stronger basal and LPS-inducible oxidative stress and inflammatory response as compared to HGFs from healthy subjects by increased p53 in mitochondria.

Synergistic Effect of Biphasic Calcium Phosphate and Platelet-Rich Fibrin Attenuate Markers for Inflammation and Osteoclast Differentiation by Suppressing NF-κB/MAPK Signaling Pathway in Chronic Periodontitis

Background: Periodontitis is characterized by excessive osteoclastic activity, which is closely associated with inflammation. It is well established that MAPK/NF-kB axis is a key signaling pathway engaged in osteoclast differentiation. It is stated that that biphasic calcium phosphate (BCP) and platelet-rich fibrin (PRF) have significant antiostoeclastogenic effects in chronic periodontitis. Objective: We aimed to elucidate the synergetic effect of PRF/BCP involvement of the nuclear factor kappa–light–chain–enhancer of activated B cells (NF-kB) and the mitogen-activated protein kinase (MAPK) signaling pathway in osteoclast differentiation in chronic periodontitis. Methods: We induced osteoclast differentiation in vitro using peripheral blood mononuclear cells (PBMCs) derived from patients with chronic periodontitis. We assessed osteoclast generation by tartrate-resistant acid phosphatase (TRAP) activity, proinflammatory cytokines were investigated by ELISA and NF-κB, and IKB by immunoblot, respectively. MAPK proteins and osteoclast transcription factors were studied by Western blot analysis and osteoclast transcriptional genes were assessed by RT-PCR. Results: The results showed that the potent inhibitory effect of PRF/BCP on osteoclastogenesis was evidenced by decreased TRAP activity and the expression of transcription factors, NFATc1, c-Fos, and the osteoclast marker genes, TRAP, MMP-9, and cathepsin-K were found to be reduced. Further, the protective effect of PRF/BCP on inflammation-mediated osteoclastogenesis in chronic periodontitis was shown by decreased levels of proinflammatory cytokines, NF-kB, IKB, and MAPK proteins. Conclusions: PRF/BCP may promote a synergetic combination that could be used as a strong inhibitor of inflammation-induced osteoclastogenesis in chronic periodontitis.

Halofuginone functions as a therapeutic drug for chronic periodontitis in a mouse model

Periodontitis is an inflammatory disease caused by host immune response, resulting in a loss of periodontium and alveolar bone. Immune cells, such as T cells and macrophages, play a critical role in the periodontitis onset. Halofuginone, a natural quinazolinone alkaloid, has been shown to possess anti-fibrosis, anti-cancer, and immunomodulatory properties. However, the effect of halofuginone on periodontitis has never been reported. In this study, a ligature-induced mice model of periodontitis was applied to investigate the potential beneficial effect of halofuginone on periodontitis. We demonstrated that the administration of halofuginone significantly reduced the expression levels of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) in vivo, and markedly suppressed immune cell infiltration into the infected sites. Furthermore, we also observed that halofuginone treatment blocked the T-helper 17 (Th17) cell differentiation in vivo and in vitro. We demonstrated for the first time that halofuginone alleviated the onset of periodontitis through reducing immune responses.

Emerging roles of Interleukin-34 together with receptor activator of nuclear factor-kB ligand and osteoprotegerin levels in periodontal disease

OBJECTIVE

The dependence between gingival crevicular fluid (GCF) of Interleukin-34 (IL-34) level and Receptor activator of nuclear factor -kB ligand/ osteoprotegerin (RANKL/OPG) ratio in the severity of periodontitis might reveal an unknown pathway of diseases with bone destruction. There is no study about the evaluation of IL-34 levels together with GCF RANKL and OPG levels in periodontitis patients before and after non-surgical periodontal treatment (NSPT). The objectives of this research were to investigate changes in the levels and relative ratios of IL-34, OPG, and RANKL in the GCF of patients with periodontitis before and after NSPT.

MATERIALS AND METHODS

20 healthy participants (CTRL), 20 patients with stage 3-grade B periodontitis and 20 with stage 3-grade C periodontitis were recruited. GCF and clinical periodontal recordings were investigated at the baseline and 6 weeks after NSPT. Enzyme-linked immunosorbent assay (ELISA) were used for quantifying of GCF IL-34, RANKL and OPG levels and their relative ratios were calculated.

RESULTS

Greater values for GCF IL-34 and RANKL levels were found in the both of periodontitis groups than in CTRL group at baseline, whereas GCF OPG levels were statistically lower at baseline (P < 0.05). GCF IL-34 and RANKL levels decreased in the 6th week after NSPT in the both periodontitis groups, while the concentration OPG levels statistically increased (P < 0.05). Significantly positive correlations among the IL-34 with RANKL, sampled-site clinical attachment level (CAL), and gingival index (GI), whereas negative correlation with OPG were reported (P < 0.05).

CONCLUSIONS

GCF IL-34 levels was high in patients with periodontitis and decreased after NSPT and its levels showed positive correlations with RANKL/OPG ratio levels CAL and GI. Determining of IL-34 levels together with RANKL/OPG ratio in GCF may therefore be valuable in detecting high risk individuals with periodontitis patients.

Two Transition Metal Coordination Polymers: Luminescent Sensing Properties and Treatment Effect on Chronic Periodontitis by Reducing IL-6 and TNF-α Content

Two novel sulfonic functionalized coordination polymers (CPs) {[Cd1.5(dimb)(5-sip)(H2O)3]·3H2O}n (1, dimb = 1,4-di(1H-imidazol-1-yl)butane) and [Co2(iptz)(Hiptz)(5-sip)(H2O)]·4H2O (2, Hiptz = 1-(4-(1H-imidazole-5-yl)phenyl)-1H-1,2,4-triazole) were acquired via different metal(II) salts reacting with the mixed ligands containing 1-(4-(1H-imidazole-5-yl)phenyl)-1H-1,2,4-triazole, 1,4-di(1H-imidazol-1-yl)butane and sodium 5-sulfoisophthalate (NaH2sip), respectively. Furthermore, the complex 1 based on Cd(II) could be utilized as the luminescent senor for picric acid (PA) detection in water. In bio-research, compounds 1 and 2 treatment effect on chronic periodontitis was assessed and the specific mechanism was discussed. First of all, the RT-PCR was performed to measure the HmuY and fimA genes relative expression level in P.gingivalis after treated by compounds 1 and 2. Then, the TNF-α and IL-6 content in the fluid of gingival crevicular after compounds treatment was determined with ELISA detection kit.

NIK inhibitor impairs chronic periodontitis via suppressing non-canonical NF-κB and osteoclastogenesis

Periodontitis is an inflammatory disease that causes damages to periodontium and alveolar bone. Overactivation and formation of osteoclasts can cause bone destruction, which contributes to periodontitis development. Receptor activator of nuclear factor κB ligand (RANKL)-mediated NF-κB signaling plays an essential role in osteoclasts differentiation. We aimed to study the effects of NIK-SMI1, an NF-κB-inducing kinase (NIK) inhibitor, on the osteoclastogenesis in vitro and periodontitis progression in vivo. A ligature-induced mice model of periodontitis was incorporated to test the potential therapeutic effect of NIK-SMI1 on periodontitis. The target protein and mRNA expression levels were determined by Western blot assay and real-time PCR assay, respectively. We found that the administration of NIK-SMI1 strongly inhibited the RANKL-stimulated non-canonical NF-κB signaling as demonstrated by decreased nuclear p52 expression and activity. Blocking NIK activity also resulted in reduced osteoclasts specific genes expression and enhanced IFN-β expression. NIK-SMI1 treatment resulted in attenuated periodontitis progression and pro-inflammatory cytokines expression in vivo. Our study suggested that NIK-SMI1 exerts beneficial effects on the mitigation of osteoclastogenesis in vitro and periodontitis progression in vivo. Application of NIK-SMI1 may serve as a potential therapeutic approach for periodontitis.

Potential Effect of Tobacco Consumption through Smoking and Chewing Tobacco on IL1beta Protein Expression in Chronic Periodontitis Patients: In Silico Molecular Docking Study

Detrimental effect of bad oral habits, such as smoking and chewing tobacco, on chronic periodontitis (CP) manifest chronic inflammation of gingival tissues which majorly results in gum bleeding, and teeth loss. A genetic association study of Interleukin 1 beta (IL1β) has been conducted in CP patients having smoking and chewing tobacco habits in regular life style. A molecular docking study has been consequently done to analyze the effect of tobacco on CP progression in depth. All statistical evaluation has been done by using SPSS v16.0. The findings of the study show the significant association of IL1β gene polymorphisms with CP increased susceptibility in combination of oral habits as mentioned earlier. The docking profile has showed the highest binding affinity of IL1β protein with the Nicotine derived Nitrosamine Ketone (NNK), one of the derivatives of nicotine which is in-taken through the habits associated with smoking and chewing tobacco. Nicotine, N-nitrosoanabasine, and N-nitrosonornicotine, the other derivatives, have also demonstrated significant impact over the IL1β protein-caused altered expression. Thus, this study concluded that the harmful effect of tobacco may increase the inflammation in periodontia by inducing the inflammatory active site of the IL1β protein in the CP patients.

Effect of VEGFC on lymph flow and inflammation-induced alveolar bone loss

The lymphatic system plays a crucial role in the maintenance of tissue fluid homeostasis and the immunological response to inflammation. The effects of lymphatic drainage dysfunction on periodontitis have not been well studied. Here we show that lymphatic vessel endothelial receptor 1 (LYVE1)+ /podoplanin (PDPN)+ lymphatic vessels (LVs) are increased in the periodontal tissues, with accumulation close to the alveolar bone surface, in two murine periodontitis models: rheumatoid arthritis (RA)-associated periodontitis and ligature-induced periodontitis. Further, PDPN+ /alpha-smooth muscle actin (αSMA)- lymphatic capillaries are increased, whereas PDPN+ /αSMA+ collecting LVs are decreased significantly in the inflamed periodontal tissues. Both mouse models of periodontitis have delayed lymph flow in periodontal tissues, increased TRAP-positive osteoclasts, and significant alveolar bone loss. Importantly, the local administration of adeno-associated virus for vascular endothelial growth factor C, the major growth factor that promotes lymphangiogenesis, increases the area and number of PDPN+ /αSMA+ collecting LVs, promotes local lymphatic drainage, and reduces alveolar bone loss in both models of periodontitis. Lastly, LYVE1+ /αSMA- lymphatic capillaries are increased, whereas LYVE1+ /αSMA+ collecting LVs are decreased significantly in gingival tissues of patients with chronic periodontitis compared with those of clinically healthy controls. Thus, our findings reveal an important role of local lymphatic drainage in periodontal inflammation-mediated alveolar bone loss. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Emerging role of long non-coding RNAs in the pathogenesis of periodontitis

Periodontitis is a bacteria-related chronic immune-associated condition that destructs bone and connective tissues around teeth. With a high incidence rate, it is regarded as a condition that impose substantial health burden. About half of the variance in the severity of periodontitis is attributed to genetic factors. Long non-coding RNAs (lncRNAs) have crucial roles in the development of several disorders such as periodontitis. A number of studies have reported dysregulation of lncRNAs such as UCA1, ANRIL, FGD5-AS1, NEAT1, FAS-AS1, Linc-RAM and NKILA in gingival tissues or blood samples of patients with periodontitis in comparison with healthy subjects. Moreover, several single nucleotide polymorphisms within lncRNAs have been associated with the susceptibility to this disorder. In the current review, we discuss the most recent articles about the role of lncRNAs in the pathogenesis of periodontitis.

Post-periodontal surgery propounds early repair salivary biomarkers by 1H NMR based metabolomics

INTRODUCTION

Oral microflora is a well-orchestrated and acts as a sequential defense mechanism for any infection related to oral disease. Chronic periodontitis is a disease of a microbial challenge to symbiosis and homeostasis. Periodontal surgery is the most promising cure with repair process during periodontal regeneration. It has an encouraging outcome in terms of early recovery biomarkers.

OBJECTIVE

Saliva of periodontal surgery subjects with the chronic periodontitis have been evaluated by ¹H NMR spectroscopy in search of possible early metabolic differences that could be obtained in order to see the eradication of disease which favours the symbiotic condition.

METHOD

The study employed ¹H NMR spectroscopy on 176 human saliva samples in search of distinctive differences and their spectral data were further subjected to multivariate and quantitative analysis.

RESULT

The ¹H NMR study of periodontal surgery samples shows clear demarcation and profound metabolic differences when compared with the diseased condition. Several metabolites such as lactate, ethanol, succinate, and glutamate were found to be of higher significance in periodontal surgery in contrast to chronic periodontitis subjects. The PLS-DA model of the studied group resulted in R² of 0.83 and Q² of 0.70.

CONCLUSION

Significant metabolites could be considered as early repair markers for chronic periodontitis disease as they are being restored to achieve symbiosis. The study, therefore, concluded the early recovery process of the diseased subjects with the restoration of possible metabolomic profile similar to the healthy controls.

The comparison of visfatin levels of gingival crevicular fluid in systemic lupus erythematosus and chronic periodontitis patients with healthy subjects

BACKGROUND

Visfatin is an adipokine and has a crucial role in pro-inflammatory response. The aim of this study was investigating the visfatin levels of gingival crevicular fluid (GCF) in patients with systemic lupus erythematosus (SLE) and chronic periodontitis and healthy subjects.

MATERIALS AND METHODS

Sixty non-obese females were selected based on their clinical parameters into four groups: 15 healthy subjects (H-H), 15 systemically healthy individuals with chronic periodontitis (H-CP), 15 SLE patient with CP (SLE-CP), and 15 SLE patients without CP (SLE-H). GCF samples were collected to estimate the levels of visfatin using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Investigating the amount of visfatin in the GCF showed that there is a significant difference between visfatin amount of GCF in SLE patients and chronic periodontitis (L-CP) in comparison with other groups (P < 0.001).

CONCLUSION

Visfatin levels have correlated positively with all the clinical periodontal parameters and its levels in (L-CP) group are highest in comparative with other groups. This finding suggests visfatin has a possible role in association between these two inflammatory conditions. Key Point • Visfatin in systemic lupus erythematosus.

Impact of resveratrol supplementation on inflammatory, antioxidant, and periodontal markers in type 2 diabetic patients with chronic periodontitis

BACKGROUND

Diabetes mellitus and periodontal disease are two common and chronic diseases with bidirectional relationship influence public health and quality of life. The aims of this study was to study the impact of resveratrol supplementation in adjunct with non-surgical periodontal therapy on inflammatory, antioxidant, and periodontal markers in patients with type 2 diabetes with periodontal disease.

MATERIALS AND METHODS

In this randomized clinical trial, 43 patients with diabetes and chronic periodontitis were randomly allocated into two intervention and control groups receiving either resveratrol supplements or placebo for 4 weeks. Serum levels of interleukin 6 (IL6), tumor necrosis factor α (TNFα), total antioxidant capacity (TAC) and clinical attachment loss (CAL) as the main index of periodontal marker were measured pre-intervention and post-intervention.

RESULTS

In the intervention group, the mean serum level of IL6 was reduced significantly (P = 0.039) post-intervention (2.19 ± 1.09 and 1.58 ± 1.06). No significant differences were seen in the mean levels of IL6, TNFα, TAC and CAL between two groups post-intervention.

CONCLUSIONS

It is suggested that daily consumption of resveratrol supplement may not change TNFα, TAC and CAL, but it would be beneficial in reducing serum levels of IL6. Therefore, further studies are suggested to investigate the effects of resveratrol supplementation along with NST on periodontal status.

Evaluation of Biochemical Parameters Present in the Saliva of Patients with Chronic Periodontitis: Results from a Meta-Analysis

AIMS

Periodontitis results from the presence of periodontopathogenic bacterial activity in the region of the gingival sulcus promoting tissue degradation and alveolar bone resorption. Biochemical analysis of the saliva can be used as a less invasive method for disease prognosis. This study aimed to evaluate the relationship between biochemical protein levels in the saliva sample of patients with chronic periodontitis and healthy patients.

MATERIALS AND METHODS

A literature review was performed using electronic databases (Cochrane Library, Google Scholar, MEDLINE, PubMed, and Web of Science) for studies published before July 2, 2016. The abstracts were evaluated, and the data extraction was performed by two calibrated examiners. The mean difference, and heterogeneity were calculated, and funnel plots were produced.

RESULTS

Twenty case-control studies were selected with 2436 patients with chronic periodontitis and 1787 controls. The meta-analysis showed that increased levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), and acid phosphatase (ACP) were all associated with periodontitis (p < 0.05), while blood urea nitrogen (BUN) and osteoprotegerin (OPG) levels did not show statistical differences between cases and controls (p > 0.05).

CONCLUSIONS

This meta-analysis evidenced that increased levels of AST, ALT, CK, gama glutamil transferase (GGT), LDH, ALP, and ACP are associated in patients with chronic periodontitis, while BUN and OPG level in saliva did not present differences between groups.

The effect of nonsurgical periodontal therapy on pentraxin 3 levels in smokers and nonsmokers with chronic periodontitis

The purpose of this study was to determine the pentraxin 3 (PTX3) levels in the gingival crevicular fluid (GCF) and saliva of smokers and nonsmokers with chronic periodontitis and to compare these levels before and after initial nonsurgical periodontal therapy. Forty subjects were divided into 2 groups with chronic periodontitis (smokers and nonsmokers) and 2 clinically healthy groups (smokers and nonsmokers). At baseline, clinical periodontal parameters, including plaque index, gingival index, probing depth, and clinical attachment levels, were assessed. Saliva and GCF samples were procured to quantify the PTX3 levels. All subjects with periodontitis, smokers and nonsmokers, received scaling and root planing. The 2 treated groups were examined 2 weeks after therapy, and any changes in the clinical parameters or PTX3 levels were recorded. At baseline, PTX3 levels in both groups of patients with chronic periodontitis were found to be significantly higher (smokers had the highest level, followed by nonsmokers) than levels in both groups of clinically healthy subjects (nonsmokers, followed by smokers) (P < 0.05). Five patients with chronic periodontitis (3 smokers and 2 nonsmokers) were lost to follow-up and therefore excluded from the statistical analysis. Scaling and root planing led to an improvement in the clinical parameters and a statistically significant reduction of PTX3 levels (P < 0.05) in both chronic periodontitis groups at the 2-week follow-up, but the changes were greater in the smokers than in the nonsmokers. In the present study, smoking was found to play a contributory role in the alteration of PTX3 levels in GCF and saliva in patients with chronic periodontitis. The role of PTX3 as a prognostic tool for resolution of periodontal inflammation still remains obscure.

Gingival crevicular fluid resistin levels in chronic periodontitis with type 2 diabetes before and after non-surgical periodontal therapy: A clinico-biochemical study

AIM

Periodontitis and diabetes mellitus share a bidirectional relationship. Resistin is an adipocytokine shown to be associated with type 2 diabetes mellitus. Hence, the present study aims to estimate the effect of non-surgical periodontal therapy (NSPT) on GCF resistin levels in healthy individuals with gingivitis and well controlled diabetics with periodontitis, and correlate the same with HbA1c levels of the diabetic subjects.

MATERIALS AND METHODS

The present study was a comparative interventional trial set in Department of Periodontics, the Oxford Dental College, Bangalore. Forty subjects participated in the study and were divided into two groups; group I (healthy individuals with gingivitis) and group II (diabetic individuals with mild to moderate periodontitis). Periodontal parameters were assessed and GCF was collected and analysed for resistin before and 3 months after NSPT.

STATISTICAL ANALYSIS

All the analysis was done using SPSS version 18. A P value of < 0.05 was considered statistically significant.

RESULTS

A significant difference was observed in GCF resistin concentrations between the two groups at baseline, wherein group II had significantly higher values. Following NSPT, there was a significant reduction in GCF resistin concentrations in both the groups, however intergroup comparison showed no difference in the amount of reduction. When all samples were analysed together, no significant correlation could be found between resistin and the parameters assessed.

CONCLUSION

Resistin levels are increased in diabetes related periodontitis. However, post treatment a similar response can be seen between healthy and well controlled diabetics. Hence, resistin can be used as an inflammatory biomarker for diabetes related periodontal disease.

Differential profiles of soluble and cellular toll like receptor (TLR)-2 and 4 in chronic periodontitis

Chronic periodontitis is a common inflammatory disease initiated by a complex microbial biofilm and mediated by the host response causing destruction of the supporting tissues of the teeth. Host recognition of pathogens is mediated by toll-like receptors (TLRs) that bind conserved molecular patterns shared by large groups of microorganisms. The oral epithelial cells respond to most periodontopathic bacteria via TLR-2 and TLR-4. In addition to the membrane-associated receptors, soluble forms of TLR-2 (sTLR-2) and TLR-4 (sTLR-4) have been identified and are thought to play a regulatory role by binding microbial ligands. sTLR-2 has been shown to arise from ectodomain shedding of the extracellular domain of the membrane receptor and sTLR-4 is thought to be an alternate spliced form. Many studies have previously reported the presence of elevated numbers of viable exfoliated epithelial cells in the saliva of patients with chronic periodontitis. The objective of this study was to investigate the potential value of salivary sTLR-2 and sTLR-4 together with the paired epithelial cell-associated TLR-2/4 mRNA as diagnostic markers for chronic periodontitis. Unstimulated whole saliva was collected after obtaining informed consent from 40 individuals with either periodontitis or gingivitis. The sTLR-2 and sTLR4 in saliva was measured by enzyme-linked immunosorbent assay. The TLR-2 and TLR-4 transcript in the epithelial cells in saliva was measured by real time polymerase chain reaction. While levels of sTLR-2 exhibited an inverse correlation, sTLR-4 positively correlated with clinical parameters in the gingivitis cohort. Interestingly, both correlations were lost in the periodontitis cohort indicating a dysregulated host response. On the other hand, while the sTLR-2 and the paired epithelial cell associated TLR-2 mRNA exhibited a direct correlation (r2 = 0.62), that of sTLR4 and TLR-4 mRNA exhibited an inverse correlation (r2 = 0.53) in the periodontitis cohort. Collectively, assessments of salivary sTLR2 and sTLR4 together with the respective transcripts in the epithelial cells could provide clinically relevant markers of disease progression from gingivitis to periodontitis.

[Expression of cytokines Il-6, IL-34 and M-CSFR in chronic periodontitis and its clinical significance]

PURPOSE

To detect the expression of IL-6，IL-34 and M-CSFR in chronic periodontitis and healthy gingival tissue and discuss the role of IL-6，IL-34 and M-CSFR in the etiology of chronic periodontitis.

METHODS

A total of 8 patients with mild chronic periodontitis and 8 patients with severe chronic periodontitis were collected in this study. As control，8 normal gingival tissues from extracted healthy were selected. The expression of IL-6, IL-34 and M-CSFR mRNA was detected by real-time PCR; the expression of IL-6, IL-34 and M-CSFR protein was detected by Western blotting. Statistical analysis was performed using GraphPad Prism 6.0.

RESULTS

The levels of IL-6, IL-34, M-CSFR mRNA and protein expression in chronic periodontitis was significantly higher than that of the normal gingival tissue(P<0.05).

CONCLUSIONS

IL-6, IL-34 and M-CSFR may be closely related to the development of chronic periodontitis.

Effect of systemic long-term, low-dose aspirin on periodontal status and soluble CD14 in gingival crevicular fluid: a case-control study

AIM

In the present study, we evaluated the effect of systemic long-term, low-dose aspirin on the periodontal status and gingival crevicular fluid (GCF) concentrations of aspirin-triggered lipoxins (ATL) and soluble CD14 (sCD14).

METHODS

The study group consisted of 45 patients who were on long-term, low-dose aspirin therapy, and the control group included patients not on aspirin therapy. Mean bleeding index, plaque index (PI), probing depth (PD), and clinical attachment loss (CAL) were recorded. GCF samples were analyzed for concentrations of ATL, and sCD14 using enzyme-linked immunosorbent assay method.

RESULTS

The means of PI, PD, and CAL were higher for the control group compared to the study group. The mean concentration of ATL was significantly higher for the study group (49.13 ± 37.39 ng/mL). The mean concentration of sCD14 was higher in the control group (5.75 ± 3.91 μg/mL). There was a negative correlation in the study group between concentrations of ATL with PD (r = -0.54) and CAL (r = -0.123). There was a positive correlation between sCD14 and CAL (r = 0.047) in the study group. A negative correlation was also observed between concentrations of sCD14 and ATL (r = -0.134) in the study group.

CONCLUSION

The results indicate better periodontal status among long-term aspirin users compared to non-aspirin users.

Superoxide Dismutase, Uric Acid, Total Antioxidant Status, and Lipid Peroxidation Assay in Chronic and Aggressive Periodontitis Patients

AIM

It has been suggested that periodontitis may be associated with increased oxidative stress. The objective of this study is to evaluate the possible differences in antioxidant status between chronic periodontitis (CP) and aggressive periodontitis (AP), by assessing the concentrations of antioxidants with total antioxi-dant status (TAS) and lipid peroxidation status in serum and gingival crevicular fluid (GCF) of these patients.

MATERIALS AND METHODS

Forty-six patients with CP, 32 patients with AP, and 50 healthy controls were included in this study. The level of enzymatic antioxidant, superoxide dismutase (SOD), nonenzymatic antioxidant uric acid, and TAS with lipid peroxidation measured in serum and GCF of patients suffering from CP and AP were compared with the healthy controls.

RESULTS

The TAS is decreased and malondialdehyde (MDA) level is increased in both serum and GCF in CP and AP compared with healthy controls (p < 0.001). Superoxide dismutase activities in GCF and serum are found to be low in both the groups of periodontitis (p < 0.001). The uric acid levels are found to be inconsistent in GCF and serum in both the groups of periodontitis.

CONCLUSION

Lipid peroxidation and TAS were affected at systemic level in serum and in GCF of the periodontal pockets, in CP and AP. Similar comments may be made for the decrease in SOD activities and inconsistent uric acid levels.

CLINICAL SIGNIFICANCE

Increased oxidative stress may have a role in the pathogenesis of periodontal disease activity.

[Expression and significance of secreted frizzled-related protein 1 and β-catenin in gingival tissue of patients with chronic periodontitis]

OBJECTIVE

This study aimed to investigate the expression and correlation of secreted frizzled-related protein 1 (SFRP1) and β-catenin in gingival tissues of patients with chronic periodontitis (CP). The role of the classical Wnt/β-catenin signaling pathway in the development of periodontitis was also explored.

METHODS

Twenty-eight patients with CP (CP group) were enrolled in this study. Among them, 16 cases were moderate CP, and 12 demonstrated severe CP. Twelve healthy cases comprised the controls (normal group). Gingival tissue was collected, and the probing depth, bleeding index, and clinical attachment loss were recorded. The expression levels of SFRP1 and β-catenin were detected by immunohistochemistry, and staining intensity was evaluated by double scoring method. SPSS 19.0 was used for statistical analysis.

RESULTS

The staining strength scores of SFRP1 and β-catenin were 2.16±0.65 and 1.12±0.51 in the normal group, 3.57±0.45 and 2.36±0.49 in the CP group, 3.61±0.40 and 2.30±0.44 in the moderate CP group, and 3.52±0.52 and 2.45±0.55 in the severe CP group, respectively. The expression of SFRP1 and β-catenin in the CP group was higher than that in the normal group (P<0.01). A significant difference was noted between the normal group and the moderate and severe CP groups (P<0.01) but none between the moderate and severe CP groups (P>0.05). A positive correlation was found between the expression of SFRP1 and β-catenin (r=0.657, P<0.01). The expression levels of β-catenin and SFRP1 were related to periodontal indexes. The correlation between the expression of SFRP1 and probing depth was most significant (r=0.723, P<0.01), as well as that between β-catenin and bleeding index (r=0.697, P<0.01).

CONCLUSIONS

Patients with CP exhibit elevated expression of SFRP1 and β-catenin in gingival tissues, and this event is related to the degree of periodontal destruction. Abnormal expression of SFRP1 and β-catenin may promote the development of periodontitis.

[Expression of miR-146a in saliva of chronic periodontitis patients and its influence on gingival crevicular inflammation and MMP-8/TIMP-1 levels]

PURPOSE

To study the expression of miR-146a in saliva of chronic periodontitis patients and its influence on gingival crevicular inflammation and MMP-8/TIMP-1 levels.

METHODS

Sixty-eight patients with chronic periodontitis treated in our hospital during March 2015 to January 2017 were chosen as the experimental group, while 50 healthy volunteers for physical examination were chosen as the control group. The level of miR-146a in saliva and inflammatory factors, MMP-8/TIMP-1 in gingival crevicular fluid were detected. Pearson test was used to assess the correlation between expression of miR-146a in saliva and the severity of disease with SPSS24.0 software package.

RESULTS

The expression of miR-146a in saliva in the experimental group was significantly higher than that in the control group(P<0.05). The level of inflammatory cytokines (IL-1β, IL-6 and IL- 35, TNF-α), the indexes of periodontal clinical symptoms (PD, AL, PLI, BI) in the experimental group were significantly higher than those in the control group (P<0.05); and MMP-8 and TIMP-1 in gingival crevicular fluid in the experimental group were significantly higher than those in the control group(P<0.05). Pearson test found that the expression of miR-146a in saliva of patients with chronic periodontitis was positively correlated with the degree of gingival inflammation, the severity of periodontal symptoms and the level of MMP-8/TIMP-1.

CONCLUSIONS

The expression of miR-146a in saliva of chronic periodontitis patients is abnormally high, and the specific expression is consistent with the degree of gingival inflammation and periodontal injury.

Assessment of Lipid Peroxidation Levels and Total Antioxidant Status in Chronic and Aggressive Periodontitis Patients: An in vivo Study

INTRODUCTION

Periodontitis is a common problem affecting a significant population of the world. For the assessment of oxidative stress of an individual, total oxidation status (TOS) and total antioxidant capacity (TAOC) are the significant biomarkers. Hence, we planned the present study to assess malondialde-hyde (MDA), TOS, TAOC levels, and oxidative stress index (OSI) in generalized aggressive periodontitis (GP) and chronic periodontitis (CP) patients.

MATERIALS AND METHODS

The present study included assessment of 40 CP patients, 40 GP patients, and 40 healthy controls. Clinical assessment of all the subjects was done by measuring the probing depth (PD), clinical attachment (CL), gingival index (GI), gingival bleeding index (GBI), and plaque index (PI). Salivary and serum samples were taken and assessed by standard procedures as described previously in the literature. All the values were assessed and compared.

RESULTS

Significant results were obtained while comparing all the periodontal parameters in between various study groups. Mean serum MDA levels in the CP, GP, and control group were found to be 0.68, 0.65, and 0.61 μM respectively. Statistically nonsignificant results were obtained while comparing the serum MDA levels in between the three study groups. Significant results were obtained while comparing the mean serum and salivary TOS values, TAOC values, and OSI in between various study groups.

CONCLUSION

In periodontitis patients, oxidative stress was significantly higher in comparison with healthy subjects.

CLINICAL SIGNIFICANCE

Oxidative parameters do play a significant role in the pathologic profile of periodontitis.

Using NMR in saliva to identify possible biomarkers of glioblastoma and chronic periodontitis

Nowadays there is increasing interest in identifying–and using–metabolites that can be employed as biomarkers for diagnosing, treating and monitoring diseases. Saliva and NMR have been widely used for this purpose as they are fast and inexpensive methods. This case-control study aimed to find biomarkers that could be related to glioblastoma (GBL) and periodontal disease (PD) and studied a possible association between GBL and periodontal status. The participants numbered 130, of whom 10 were diagnosed with GBL and were assigned to the cases group, while the remaining 120 did not present any pathology and were assigned to the control group. On one hand, significantly increased (p < 0.05) metabolites were found in GBL group: leucine, valine, isoleucine, propionate, alanine, acetate, ethanolamine and sucrose. Moreover, a good tendency to separation between the two groups was observed on the scatterplot of the NMR. On the other hand, the distribution of the groups attending to the periodontal status was very similar and we didn´t find any association between GBL and periodontal status (Chi-Square 0.1968, p = 0.91). Subsequently, the sample as a whole (130 individuals) was divided into three groups by periodontal status in order to identify biomarkers for PD. Group 1 was composed of periodontally healthy individuals, group 2 had gingivitis or early periodontitis and group 3 had moderate to advanced periodontitis. On comparing periodontal status, a significant increase (p < 0.05) in certain metabolites was observed. These findings along with previous reports suggest that these could be used as biomarkers of a PD: caproate, isocaproate+butyrate, isovalerate, isopropanol+methanol, 4 aminobutyrate, choline, sucrose, sucrose-glucose-lysine, lactate-proline, lactate and proline. The scatter plot showed a good tendency to wards separation between group 1 and 3.

Saliva, Serum Levels of Interleukin-21, -33 and Prostaglandin E2 in Patients with Generalised Aggressive or Chronic Periodontitis

PURPOSE

This cross-sectional study aims to evaluate saliva, serum levels of interleukin-21 (IL-21), IL-33, and prostaglandin E2 (PGE2) in patients with generalised chronic periodontitis or aggressive periodontitis.

MATERIALS AND METHODS

Before initiation of any periodontal treatment, saliva and serum samples were collected and clinical periodontal measurements were recorded from 94 participants (25 aggressive periodontitis patients, 25 chronic periodontitis patients, 44 periodontally healthy individuals). IL-21, IL-33 and PGE2 levels in serum and saliva samples were determined by ELISA. Data were tested statistically using Kruskal-Wallis, Mann-Whitney U-, and Spearman-rho rank tests.

RESULTS

Saliva IL-33 levels were statistically significantly higher in the chronic than the aggressive group (p < 0.05). Serum IL-33, saliva and serum IL-21 and PGE2 levels were similar in the two periodontitis groups. Saliva IL-33 levels correlated with age in the chronic periodontitis group (p < 0.05). Statistically significant positive correlations were found between serum, saliva PGE2 levels and plaque index (p < 0.05). IL-33 and IL-21 levels in serum samples positively correlated in the periodontitis groups (p < 0.05).

CONCLUSION

IL-21 and PGE2 analysis did not exhibit discriminating data between generalised chronic and aggressive periodontitis, but the present findings support the role of these cytokines in periodontitis. Statistically significantly higher saliva IL-33 levels in the chronic periodontitis group warrant further research.

Evaluation of Resistin Levels in Saliva of Patients with Chronic Periodontitis and Healthy Subjects

OBJECTIVE

To evaluate resistin levels in the saliva of patients with chronic periodontitis, and healthy subjects.

METHODS

Thirty-four subjects aged between 25 and 50 years were included and divided into healthy group (n = 19) and chronic periodontitis group (n = 15). The saliva levels of resistin were assessed by enzyme-linked immunosorbent assay. Comparisons of resistin levels between the two groups were made with the Mann-Whitney Test.

RESULTS

The chronic periodontitis group showed significantly higher resistin levels than the control group (P = 0.001).

CONCLUSION

The level of resistin in saliva might help to determine the inflammatory status of periodontal diseases.

Effect of Periodontal Treatment on the Crevicular Level of High-mobility Group Box 1 and Soluble Triggering Receptor Expressed on Myeloid Cells 1 in Patients with Chronic Periodontitis

The present study aimed to compare the levels of high-mobility group box 1(HMGB1) and soluble triggering receptor expressed on myeloid cells (sTREM1) in the gingival crevicular fluid (GCF). This cross-sectional cohort trial investigated two groups of 22 eligible chronic periodontitis and 22 periodontally healthy individuals (student volunteers) both before and after the periodontal treatment.  GCF was collected from the deepest pockets with clinical attachment loss≥3 mm. Both groups received oral hygiene instructions, and scaling and root planning were performed in the test group. Enzyme-linked immunosorbent assay kit (ELISA) was used to measure the levels of HMGB1 and sTREM1 in GCF samples collected before and 1 month after non-surgical periodontal treatment. The results showed that HMGB1 levels were significantly higher in the chronic periodontitis patients than those of the healthy individuals before treatment (p<0.02) and decreased significantly after periodontal treatment, which reduced gingival inflammation. Furthermore, the levels of sTREM1 marker were significantly higher in periodontitis patients before (p<0.001) and 1 month after treatment than in healthy individuals (p<0.003) although its crevicular levels decreased after periodontal therapy in periodontitis group. The higher levels of sTREM1 and HMGB1 cytokines in GCF of periodontitis patients and the significant decrease after the introduction of the periodontal treatment underlines the importance of HMGB1 and sTREM1 in pathogenesis of periodontitis.

Effects of vector ultrasonic system debridement and conventional instrumentation on the levels of TNF-α in gingival crevicular fluid of patients with chronic periodontitis

BACKGROUND

Tumor necrosis factor alpha (TNF-α) is an inflammatory mediator whose levels are increased in the gingival crevicular fluid and blood serum in the case of chronic periodontitis.

OBJECTIVES

The aim of this study was to determine the effect of vector ultrasonic system (VUS) on the levels of TNF-α in gingival crevicular fluid (GCF) and the clinical parameters in patients with chronic periodontitis.

MATERIAL AND METHODS

The study protocol was conducted using split-mouth design in 30 patients with chronic periodontitis. VUS and scaling and root planing (S/RP) were applied separately to 2 quadrants, including the upper and the lower jaws. At baseline and after 6 months, clinical parameters including plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL) were recorded, and concentrations of TNF-α in GCF were determined by enzyme-linked immunosorbent assay (ELISA). Intergroup comparisons were evaluated by the independent Students' t-test, and the Pearson correlation was used to determine the relationship between parameters. The level of significance was set at 5%.

RESULTS

Both treatment modalities provided statistically significant improvements in clinical periodontal parameters and TNF-α levels after 6 months (p < 0.05). Also, there were no significant correlations between the TNF-α levels in GCF and the clinical parameters in both treatment group at baseline and at the end of 6 months period (p > 0.05).

CONCLUSIONS

The use of the vector ultrasonic system in the non-surgical treatment of chronic periodontitis presents beneficial improvements for the clinical attachment level and the probing pocket depth as well as TNF-α levels in GCF.

Association between interleukin-8 levels and chronic periodontal disease: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Current publications present contradictory findings regarding interleukin-8 (IL-8) levels in patients with chronic periodontitis (CP). This systematic review compile evidences of the IL8 mRNA and protein levels in gingival tissue, saliva, and gingival crevicular fluid (GCF) investigated in patients with CP. Moreover, 2 meta-analyses were made focusing on the IL-8 levels in GCF and saliva of patients with or without CP.

METHODS

Electronic searches of the PubMed, Web of Science, and Scopus databases were conducted for publications up to February 2016 that investigated the levels of IL-8 detected in individuals with CP compared with health individuals. A total of 31 publications were included in the systematic review. For meta-analyses, the strength of association was calculated by pooled odds ratios with 95% confidence intervals using RevMan 5.1 software. Heterogeneity was examined using Higgins I-squared, tau-squared, and χ tests.

RESULTS

In biopsies of gingival tissue of CP patients, all studies found higher IL8 mRNA levels, and the majority of studies showed higher IL-8 protein levels in this tissue of individuals with moderate to severe CP. Four studies investigating the IL-8 levels in saliva showed inconclusive results. In spite of some studies seemed to indicate higher levels of IL-8 in GCF of CP patients, the meta-analysis results showed significantly lower IL-8 levels (pg/μL) in GCF of CP patients in comparison with periodontally healthy subjects.

CONCLUSIONS

We concluded that IL8 gene expression and IL-8 protein levels were higher in gingival tissues of CP patients when compared to periodontally health individuals. Meta-analysis of studies that measured IL-8 (pg/uL) in GCF found lower levels in CP patients. There are conflicting evidences regarding IL-8 levels in saliva.

[Detection of Dickkopf-1 and alkaline phosphatase activity in gingival crevicular fluid from chronic periodontitis with Er:YAG laser as an adjunctive treatment]

PURPOSE

The aim of this study was to evaluate the clinical efficacy and the level of DKK1 and alkaline phosphatase (ALP) activity in gingival crevicular fluid (GCF) while taking Er:YAG laser as an adjunctive to scaling and root planning in the treatment of chronic periodontitis (CP).

METHODS

Eleven patients with CP were included and there were nineteen pairs of homonym teeth(thirty-eight teeth) in this split-mouth design, and they were randomly assigned to experimental group or control group. In the experimental group, a combination of ultrasonic subgingigval scaling and root planning with hand instrument (SRP) were performed with Er: YAG laser as an adjunctive; in the control group, only SRP was performed. The main variables were bleeding index (BI), probing depth (PD), clinical attachment loss (CAL) which were assessed at baseline (1 week after ultrasonic subgingival scaling), l month and 3 months after treatment. GCF was collected at baseline, l week, l month and 3 months, and the levels of DKK1 and ALP activity were detected at the same time point. The data were analyzed with SPSS 19.0 software package.

RESULTS

Both groups showed significant reduction of PD, CAL, BI values 1 month and 3months after treatment, but no significant difference in clinical parameters were found between the two groups. In the experimental group, the activity of ALP reduced to (386.69±146.42), (341.221±171.62), (249.27±98.72) from (396.191±150.55) U/L and the level of DKK1 dropped to (310.34±184.68), (270.04±55.14), (247.31±56.99) from (307.12±45.63) μg/L at the end of 1 week, 1 month, 3 months, respectively. Meanwhile, in the control group, the activity of ALP reduced to (374.72±131.27), (344.42±127.80), (252.36±90.4 ) from (394.09±120.25) U/L and the level of DKK1 dropped to (310.34±84.68), (270.04±55.14), (247.31±56.99) from (305.33±147.40) μg/L at the end of l week, l month, 3months, respectively. There is no significant difference between the two groups at any period for ALP or DKK1.

CONCLUSIONS

Er:YAG laser was a safe no-surgical adjunctive therapy in treating chronic periodontitis, further observation is needed to determine its long-term effectiveness.

Trace Mineral Micronutrients and Chronic Periodontitis-a Review

Trace mineral micronutrients are imperative for optimum host response. Populations worldwide are prone to their insufficiency owing to lifestyle changes or poor nutritional intake. Balanced levels of trace minerals like iron (Fe), zinc (Zn), selenium (Se) and copper (Cu) are essential to prevent progression of chronic conditions like periodontitis. Their excess as well as deficiency is detrimental to periodontal health. This is specifically true in relation to Fe. Furthermore, some trace elements, e.g. Se, Zn and Cu are integral components of antioxidant enzymes and prevent reactive oxygen species induced destruction of tissues. Their deficiency can worsen periodontitis associated with systemic conditions like diabetes mellitus. With this background, the present review first focusses on the role of four trace minerals, namely, Fe, Zn, Se and Cu in periodontal health followed by an appraisal of the data from case control studies related to their association with chronic periodontitis.

Salivary IgA, Interleukin-1β and MMP-8 as Salivary Biomarkers in Chronic Periodontitis Patients

OBJECTIVE

To compare the clinical parameters and levels of salivary immunoglobulin A (IgA), Interleukin-1β (IL-1β) and matrix metalloproteinase-8 (MMP-8) in patients with moderate to severe chronic periodontitis and in individuals with healthy gingiva.

METHODS

Levels of clinical parameters plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL) and bleeding on probing (BOP) along with salivary biomarkers salivary IgA, IL-1β and MMP-8 were recorded among 50 adults (30 test subjects with moderate to severe generalised chronic periodontitis, constituting group A, and 20 periodontally healthy controls - group B). Clinical evaluation was done before oral prophylaxis, and 6 weeks and 12 weeks after oral prophylaxis, and saliva samples were obtained before and 12 weeks after oral prophylaxis. Salivary IgA, IL-1β and MMP-8 levels in saliva were assessed using enzyme-linked immunosorbent assay.

RESULTS

In group A, there were highly significant differences in terms of PI, GI, PD, CAL and BOP before oral prophylaxis, and 6 weeks and 12 weeks after oral prophylaxis when compared at these intervals. Differences in their levels in group B were non-significant at such intervals except PI. Mean levels of salivary IgA, IL-1β and MMP-8 in chronic periodontitis patients at baseline were significantly higher than in the periodontally healthy group. Their levels in group A decreased significantly 12 weeks after oral prophylaxis, but remained static in group B.

CONCLUSION

The levels of salivary IgA, IL-1β and MMP-8 showed significant reduction after oral prophylaxis, suggesting that these biomarkers could facilitate the screening, early diagnosis, and management of periodontal disease.

[Local immune and oxidative status in exacerbated chronic apical periodontitis]

The aim of the study was to define local immune and oxidative changes in patients with exacerbated chronic apical periodontitis. These changes were assessed in saliva of 67 patients with the mean age of 31±2.5 before and after treatment. The study revealed disturbances in cytokines and complement system balance and activation of lipids peroxidation. Combination of Gepon or Vobenzim with Essentiale forte H and Kaskatol proved to be the most effective for correction of this imbalance.

[The role of free-radical oхidation for patogenesis of chronic generalization periodontitis in elderly age patients]

In old aged patients with chronic generalized periodontitis and cardiovascular diseases the level lipoperoxidation increased and antioхidation protection decreased in saliva and blood. After the course of treatment myocardial ischemia and diseases chronic periodontal inflammation the level of lipoperoхidation was changed insignificant accompanied with decreased of TBK-active substance in saliva and blood. Change of nitric oхide after by treatment was depended it initial level before treatment and often had an opposite orientation.

Interleukin-33 and RANK-L Interplay in the Alveolar Bone Loss Associated to Periodontitis

Introduction

Chronic Periodontitis (CP) is an inflammatory disease of bacterial origin that results in alveolar bone destruction. Porphyromonas gingivalis (Pg), one of the main periopathogens, initiates an inflammatory cascade by host immune cells thereby increasing recruitment and activity of osteoclasts, the bone resorbing cells, through enhanced production of the crucial osteoclastogenic factor, RANK-L. Antibodies directed against some cytokines (IL-1β, IL-6 and TNF-α) failed to exhibit convincing therapeutic effect in CP. It has been suggested that IL-33, could be of interest in CP.

Objective

the present study aims to analyze whether and how IL-33 and RANK-L and/or their interplay are involved in the bone destruction associated to CP.

Material and Methods

mRNAs and protein expressions of IL-33 and RANK-L were analyzed in healthy and CP human gingival samples by immunohistochemistry (IHC) and RT-qPCR. Murine experimental periodontitis (EP) was induced using Pg infected ligature and Pg free ligature around the first maxillary molar. Alveolar bone loss was recorded by μCT. Mouse gingival explants were stimulated for 24 hours with IL-33 and RANK-L mRNA expression investigated by RT-qPCR. Human oral epithelial cells were infected by Pg for 6, 12; 24 hours and IL-33 and RANK-L mRNA expressions were analyzed by RT-qPCR.

Results

IL-33 is overexpressed in gingival epithelial cells in human affected by CP as in the murine EP. In human as in murine gingival cells, RANK-L was independently induced by Pg and IL-33. We also showed that the Pg-dependent RANK-L expression in gingival epithelial cells occured earlier than that of IL-33.

Conclusion

Our results evidence that IL-33 overexpression in gingival epithelial cells is associated with CP and may trigger RANK-L expression in addition to a direct effect of Pg. Finally, IL-33 may act as an extracellular alarmin (danger signal) showing proinflammatory properties in CP perpetuating bone resorption induced by Pg infection.

Biomarker levels in gingival crevicular fluid of subjects with different periodontal conditions: A cross-sectional study

OBJECTIVE

To compare five biomarker levels in gingival crevicular fluid (GCF) in different tooth-sites of subjects with healthy periodontium, aggressive periodontitis and severe chronic periodontitis, and to evaluate the value of these biomarker levels for diagnosis of the type and activity of periodontitis.

MATERIALS AND METHODS

Prior to therapy, GCF samples were collected using filter paper strip at different tooth-sites of 10 subjects with healthy periodontium (H), 15 with severe chronic periodontitis (CP) and 15 with aggressive periodontitis (AgP). The strips were weighed and the periodontal clinical parameters were recorded. Levels of interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), and alkaline phosphatase (ALP) in GCF were assessed by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The volumes of the GCF samples obtained in CP and AgP subjects were significantly higher than those from subjects with healthy periodontium (P<0.05). Levels of IL-6, TNF-α, CRP and ALP were significantly higher in the untreated disease sites in the CP and AgP groups compared to those in control sites in the H group, while IL-10 levels were lower in the CP and AgP groups than those in the control sites in the H group. However, the levels of all five biomarker levels showed significant correlation with the clinical parameters.

CONCLUSION

The measurement of five biomarker levels in GCF may facilitate overall screening of periodontitis patients in epidemiological studies and allow estimation of periodontitis activity.

Cytokine and metalloproteinases in gingival fluid from patients with chronic periodontitis

The purpose of the present research was to determine the levels of IL- 1a, IL- 1 P, TNF-a, IL-6, IL-6sR, IL-8, IL-10, MMP-3 and EMP-8 in gingival crevicular fluid (GCF) of subjects with chronic periodontitis. Clinical measurements were carried out in 20 patients with chronic periodontitis and 11 periodontally healthy controls. The clinical indexes evalua- ted were: gingival index (GI), plaque index (PI), bleeding on probing (BOP), probing depth (PD) and clinical attachment loss (CAL); the measurements were taken at six sites per tooth in all teeth in each subject. GCF samples were taken from one tooth per quadrant, and the levels of mediators were measured using an ELISA test. Statistically significant differences were observed between patients and control group in relation to all clinical parameters evaluated (p<0.05). The gingival concentrations, in pg/mL, of IL-la (patients: 239.06 ± 65.5 vs control: 97.79 ± 15.81), IL-10 (patients: 157.19 ± 36.4 vs control: 63.44 ± 19.04), TNF-a (patients: 10.87 ± 1.7 vs control: 1.15 ± 0.84), IL-6 (patients: 3.77 ± 1.7 vs control: 0.43 ± 0.22), IL-6Sr (patients: 655.59 ± 185.8 vs control: 73.59 ± 23.18), IL-8 (patients: 496.3 ± 155.3 vs control: 206.13 ± 46.63), IL-10 (patients: 10.75 ± 3.6 vs control: 2.41 ± 0.57), MMP-3 (patients: 3531 ± 1558.2 vs control: 724.84 ± 289.51) and MMiP-8 (patients: 8231.70 ± 1279.2 vs control: 1534.67± 814.90) were significantly greater in patients with periodontal disease than in the control group (p<0.00 1). The higher levels of the cytokines and metalloproteinases obtained in this study were significantly associated with the severity of the periodontal disease.

[Expressions of EMMPRIN and its ligand CyPA in gingival crevicular fluid of chronic periodontitis patients]

PURPOSE

To detect the expressions of EMMPRIN and its ligand CyPA in gingival crevicular fluid (GCF) of chronic periodontitis (CP) patients and explore their possible relation to the status of periodontal inflammation.

METHODS

GCF of CP patients (group CP) and periodontitis-free patients with intact dentition (the control group) were collected and assayed for EMMPRIN and CyPA expressions by ELISA. The clinical periodontal status of these patients were examined. Statistical analysis was performed by use of SPSS 17.0 software package. Spearman's correlation analysis was utilized to determine the relationships between the expressions of EMMPRIN and CyPA in GCF and the clinical parameters. In addition, analysis of variance (ANOVA) was used for comparing the difference between group CP and the control group.

RESULTS

In group CP, GCF volume was positively correlated with EMMPRIN total amount, CyPA total amount and some clinical periodontal indexes (GI,SBI,AL). EMMPRIN total amount was positively correlated with GCF volume, CyPA total amount and some of clinical periodontal indexes (GI,SBI,AL), but it was negatively correlated with smoking status (P<0.05). Moreover, CyPA total amount was positively correlated with GCF volume, EMMPRIN total amount and some of clinical periodontal indexes (GI,SBI,AL). In the control group,there were significant positive correlations among GCF volume, EMMPRIN total amount and CyPA total amount. The difference of GCF, EMMPRIN and CyPA between the 2 groups were statistically significant (P<0.05).

CONCLUSIONS

EMMPRIN and its ligand CyPA in GCF of periodontitis-free patients with intact dentition and CP patients were all detected. As the progress of periodontal inflammation, GCF secretion increases, as well as the expressions of EMMPRIN and CyPA in GCF.

Nonsurgical periodontal therapy with/without diode laser modulates metabolic control of type 2 diabetics with periodontitis: a randomized clinical trial

In order to evaluate whether nonsurgical periodontal treatment with/without diode laser (DL) decontamination improves clinical parameters, the levels of IL-1β, IL-6, IL-8, intercellular adhesion molecule (ICAM), and vascular cell adhesion molecule (VCAM) in gingival crevicular fluid and metabolic control (HbA1c) in chronic periodontitis (CP) patients with diabetes mellitus type 2 (DM2). Sixty patients with DM2 and CP were randomly assigned into two groups to receive scaling and root planing (SRP, n = 30) or SRP followed by diode laser application (SRP + DL, n = 30). Clinical periodontal and gingival crevicular fluid (GCF) parameters were assessed at baseline, 1, and 3 months after periodontal treatment. HbA1c levels were evaluated at baseline and 3 months post-therapy. Total amounts of cytokines and molecules were analyzed by ELISA. Nonsurgical periodontal treatment with/without DL appeared to improve clinical, biochemical parameters, and glycemic control in DM2 patients (BMI < 25 kg/m(2)) with CP. The SRP + DL group provided better reductions in probing depth (PD) and clinical attachment level (CAL) parameters compared to the SRP group (P < 0.05). Significant reductions were found in the total amounts of GCF levels of IL-1, IL-6, IL-8, ICAM, and VCAM after treatment (P < 0.05). HbA1c levels decreased significantly at 3 months after treatment (P < 0.05). SRP + DL reduced HbA1c levels more significantly compared to SRP alone (0.41 vs. 0.22 %, P < 0.05). SRP, especially in combination with DL, shows improvement of glycemic control for DM2 patients with CP.

Serine dipeptide lipids of Porphyromonas gingivalis inhibit osteoblast differentiation: Relationship to Toll-like receptor 2

Porphyromonas gingivalis is a periodontal pathogen strongly associated with loss of attachment and supporting bone for teeth. We have previously shown that the total lipid extract of P. gingivalis inhibits osteoblast differentiation through engagement of Toll-like receptor 2 (TLR2) and that serine dipeptide lipids of P. gingivalis engage both mouse and human TLR2. The purpose of the present investigation was to determine whether these serine lipids inhibit osteoblast differentiation in vitro and in vivo and whether TLR2 engagement is involved. Osteoblasts were obtained from calvaria of wild type or TLR2 knockout mouse pups that also express the Col2.3GFP transgene. Two classes of serine dipeptide lipids, termed Lipid 654 and Lipid 430, were tested. Osteoblast differentiation was monitored by cell GFP fluorescence and osteoblast gene expression and osteoblast function was monitored as von Kossa stained mineral deposits. Osteoblast differentiation and function were evaluated in calvarial cell cultures maintained for 21 days. Lipid 654 significantly inhibited GFP expression, osteoblast gene expression and mineral nodule formation and this inhibition was dependent on TLR2 engagement. Lipid 430 also significantly inhibited GFP expression, osteoblast gene expression and mineral nodule formation but these effects were only partially attributed to engagement of TLR2. More importantly, Lipid 430 stimulated TNF-α and RANKL gene expression in wild type cells but not in TLR2 knockout cells. Finally, osteoblast cultures were observed to hydrolyze Lipid 654 to Lipid 430 and this likely occurs through elevated PLA2 activity in the cultured cells. In conclusion, our results show that serine dipeptide lipids of P. gingivalis inhibit osteoblast differentiation and function at least in part through engagement of TLR2. The Lipid 430 serine class also increased the expression of genes that could increase osteoclast activity. We conclude that Lipid 654 and Lipid 430 have the potential to promote TLR2-dependent bone loss as is reported in experimental periodontitis following oral infection with P. gingivalis. These results also support the conclusion that serine dipeptide lipids are involved in alveolar bone loss in chronic periodontitis.