Aberrant pulmonary immune response of obese mice to periodontal infection.

Obesity and periodontitis constitute mutual risk factors in respiratory disorders; this study aimed to explore the pulmonary immune response to periodontal infection using combined animal models with diet-induced obesity (DIO). Thirty-two C57 BL/6J mice were randomly divided into low-fat (LF) or high-fat (HF) diet groups and fed an LF diet as a control or an HF diet to induce obesity. The 30-week mice in the diet group were divided into periodontal ligation group (10 days using Porphyromonas gingivalis ATCC 33277) or sham-ligation group. The expressions of the macrophage-specific maker (F4/80), macrophage chemotactic protein1 (MCP1), and inflammatory cytokines in lung tissues were analyzed. The mRNA and protein levels of F4/80, MCP1, interleukin (IL)-1ß, and IL-6 expressions were significantly upregulated by obesity in lung tissues. However, the mRNA and protein levels of F4/80, MCP1, and IL-6 were downregulated by periodontitis in DIO mice relative to that of the HF control group. Periodontitis increased tumor necrosis factor-α level of lung tissues under LF, while IL-10 was not affected by obesity regardless of periodontitis. Periodontitis may aggravate pulmonary immune response in obese rodents. This may relate to the imbalance of the pro- and anti-inflammatory cytokine status of lung lesions, which tends to attenuate the infiltration of alveolar macrophages.

Aberrant Periodontal and Systemic Immune Response of Overweight Rodents to Periodontal Infection.

This study aimed to explore periodontal and systemic immune response of overweight hosts to periodontitis. Forty C57 BL/6J male mice were divided into high (HF) or low fat (LF) diet groups and fed with the two diets, respectively, for 8 weeks. Each diet group was then divided into periodontitis (P) or control (C) groups (n = 10 per group) for 10-day ligation or sham-ligation. Overweight-related parameters including body weight were measured. Alveolar bone loss (ABL) was morphometrically analyzed and periodontal osteoclasts were stained. Periodontal immune response including leukocyte and macrophage number and inflammatory cytokines were analyzed by histology and quantitative PCR. Serum cytokine and lipid levels were quantified using electrochemiluminescence immunoassays, enzyme-linked immunosorbent assays, and biochemistry. It was found that HF group had 14.4% body weight gain compared with LF group (P < 0.01). ABL and periodontal osteoclast, leukocyte, and macrophage number were higher in P group than C group regardless of diet (P < 0.05). ABL and periodontal osteoclast number were not affected by diet regardless of ligation or sham-ligation. Leukocyte and macrophage number and protein level of tumor necrosis factor α (TNF-α) in periodontium and serum interleukin-6 level were downregulated by HF diet in periodontitis mice (P < 0.05). Periodontal protein level of TNF-α was highly correlated with serum interleukin-6 and low-density lipoprotein cholesterol levels (P < 0.01). These findings indicated that impaired immune response occurs both periodontally and systemically in preobesity overweight individuals. Given a well-reported exacerbating effect of obesity on periodontitis, overweight, if let uncontrolled, might place the individuals at potential risk for future periodontal tissue damage.

A survey on the prevalence and risk indicators of erosive tooth wear among adolescents in Guangzhou, South China.

BACKGROUND: Erosive tooth wear (ETW) has become a crucial oral health problem over the decades in China. OBJECTIVES: To explore the prevalence and risk indicators of ETW among adolescents in Guangzhou, south China. METHODS: A cross-sectional survey of 720 participants was conducted in Guangzhou, using an equal-sized, stratified, multistage random sampling approach. The participants were from two different age groups (12- and 15-year-olds), 360 per group. The ratio of males to females was 1:1 in each group. ETW was recorded utilising the basic erosive wear examination (BEWE) index as the dependent variable. Independent variables included age, gender, region, socioeconomic status, dietary factors, oral health measures and others. RESULTS: The prevalence rates (weighted) of ETW and dentin exposure (DE) were 56.1% and 26.2% among adolescents in Guangzhou, with mean teeth (weighted) of 1.8 ± 2.5 and 0.6 ± 1.5, respectively. No matter the prevalence or the mean teeth, the 15-year-olds were higher than the 12-year-olds; the mean teeth of ETW of males was higher than that of females; the mean teeth of ETW and DE of the adolescents of low socioeconomic status were higher than those of high socioeconomic status. Medium to high risk levels were found for 10.1%. In the multiple regression model, age, gender and taking acidic foods/drinks before sleep were associated with ETW. CONCLUSIONS: Moderate ETW in the permanent dentition was common among adolescents in Guangzhou. However, the teeth involved were low. Dietary factors and demographics were the main risk indicators.

[Impacts of periodontitis on visceral organ weight and weight percentage in obese mice].

OBJECTIVE: This study aimed to explore the impacts of periodontitis on the visceral weight and weight percentage of obese animal models. METHODS: A total of 64 C57BL/6J mice were divided into the following diet groups: high-fat diet (HFD) group (n=36), which was fed with high-fat diet to induce obesity, and low-fat diet (LFD) group (n=28), which was fed with low-fat diet as the control. After 16 weeks on diet, each diet group was divided into periodontitis (P) and control (C) groups. The P groups were induced for periodontitis by ligation with Porphyromonas gingivalis-adhered silk for 5 or 10 days, and the C groups were sham-ligated as the control. Visceral organs were resected and weighed. The organ weight percentage was calculated. RESULTS: Compared with the LFD group, the HFD group significantly upregulated the weight and weight percentage of visceral adipose tissue and spleen (P<0.05), upregulated the weight of liver and kidney (P<0.05), and downregulated the weight percentage of liver and kidney (P<0.01). In the HFD group, the weight and weight percentage of spleen were downregulated in the P group (P<0.05), but were upregulated in the 10-day group compared with the 5-day group (P<0.05). CONCLUSIONS: Periodontitis can affect the general morphology of the viscera (especially spleen) in obese animal models. Pathological indications in terms of immunometabolism might be present in the correlation between obesity and periodontitis.

Postoperative Weight Loss Masks Metabolic Impacts of Periodontitis in Obese Rodents.

BACKGROUND: Postoperative weight loss (POWL) is expected to occur in combined models of obesity and periodontitis. This study explores the confounding effects of POWL on the impact of ligation-induced periodontitis on glucose and lipid metabolism in obese animals. METHODS: Combined mouse models of diet-induced obesity (DIO) and ligation-induced periodontitis (5- or 10-day ligation) were studied. Fasting serum glucose (FSG), fasting insulin (Fins), and lipids including triglyceride (TG), total cholesterol (TC), and low- and high-density lipoprotein cholesterol (HDLC), were detected via biochemistry and enzyme-linked immunosorbent assay. POWL and homeostasis model assessment of insulin resistance (HOMA-IR) were calculated. Analysis of covariance was performed to identify confounding effects of POWL. RESULTS: The obesity, periodontitis, and 10-day groups exhibited greater POWL than corresponding controls (P <0.01). Without considering POWL, conflicting results were found, including: 1) contradictory changes in HDLC caused by obesity or periodontitis; and 2) unequal levels of FSG, TC, and HDLC between days 5 and 10 in the sham-ligation controls. Moreover, upregulating effects of periodontitis were found only on TG in the DIO mice, whereas those on Fins, HOMA-IR, and HDLC were statistically veiled. After the confounding effects of POWL were filtered, periodontitis promoted increased levels of not only TG but also Fins, HOMA-IR, and HDLC in the DIO mice (P <0.05). CONCLUSIONS: When analyzing the interrelationship between obesity and periodontitis, the confounding effects of an imbalanced POWL should be considered. Otherwise, impact of periodontitis on metabolic dysregulation in obese animals may be underestimated.

Macrophages Play a Key Role in the Obesity-Induced Periodontal Innate Immune Dysfunction via Nucleotide-Binding Oligomerization Domain-Like Receptor Protein 3 Pathway.

BACKGROUND: Obesity is associated with infiltration of macrophages into adipose tissue. However, effects of obesity on macrophage infiltration and activation in periodontal tissues with periodontitis are still to be elucidated. METHODS: A diet-induced obesity 16-week mouse model was constructed, and periodontitis was induced by periodontal ligation for 10 days. The model consisted of periodontitis (P) and control (C) groups, with high fat (HF) and normal (N) diet conditions. Bone loss (BL) was analyzed by microcomputed tomography. In periodontal tissues, immunohistochemical staining and quantitative polymerase chain reaction (qPCR) detected expressions of: 1) nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) pathway; 2) macrophage-specific marker (F4/80); and 3) macrophage chemotactic protein 1 (MCP1). Bone marrow-derived macrophages (BMDMs) from the mouse model were stimulated by Porphyromonas gingivalis lipopolysaccharide (LPS) in vitro (NC/NC + LPS: BMDMs from NC group without/with LPS stimulation; HFC/HFC + LPS: BMDMs from HFC group without/with LPS stimulation). Expressions of NLRP3 pathway in BMDMs were detected by immunocytochemical staining and qPCR. RESULTS: BL increased significantly with periodontitis (NC versus NP; HFC versus HFP) and obesity (NP versus HFP). Expressions of NLRP3 pathway were significantly elevated in gingival tissues with periodontitis (NC versus NP; HFC versus HFP), but not with obesity (NC versus HFC; NP versus HFP). F4/80 and MCP1 expressions were significantly upregulated in gingival tissues with periodontitis (NC versus NP; HFC versus HFP) but significantly downregulated in the context of obesity (NP versus HFP). In vitro, NLRP3 pathway expressions were significantly upregulated in BMDMs after LPS stimulation (NC + LPS versus NC; HFC + LPS versus HFC), but significantly downregulated in HFC groups (HFC versus NC; HFC + LPS versus NC + LPS). CONCLUSION: Obesity may paralyze innate immune response of periodontium via attenuating infiltration and activation of macrophages and further aggravate periodontal disease.

Enhanced Activity of the Macrophage M1/M2 Phenotypes and Phenotypic Switch to M1 in Periodontal Infection.

BACKGROUND: Macrophages are central players in the pathogenesis of periodontitis. However, the phenotypic switch of macrophage M1/M2 remains uncertain. METHODS: Adult male mice were divided into periodontitis (P) or control (C) groups. Bone marrow-derived macrophages (BMMs) were stimulated with Porphyromonas gingivalis lipopolysaccharide (LPS). In both the periodontium and serum, macrophage M1 and M2 phenotypes were detected in vivo and in vitro via the following: 1) immunofluorescence; 2) immunohistochemistry; 3) electrochemiluminescence immunoassays; 4) quantitative polymerase chain reaction assays; and 5) enzyme-linked immunosorbent assays. The M1-type markers used included the following: 1) nitric oxide synthase (NOS)-2; 2) tumor necrosis factor-alpha; 3) interleukin (IL)-1ß; 4) IL-6; and 5) C-reactive protein. The M2-type markers were as follows: 1) arginase-1; 2) cluster of differentiation (CD) 206; and 3) IL-10. RESULTS: Compared with the C group, the P group had a 14-fold increase in F4/80(+) NOS2(+) cells and four-fold more F4/80(+) CD206(+) cells with an enhanced NOS2/CD206 ratio in the periodontium (P <0.01). NOS2(-) CD206(+) and dual NOS2(+) CD206(+) macrophages dominated in the C and P groups, respectively. The P group had significantly increased M1- and M2-type cytokines in both the periodontium and serum and also had an enhanced IL-6/IL-10 ratio in the serum (P <0.05). M1-type markers were significantly upregulated at the mRNA level, whereas M2-type markers were downregulated at both the mRNA and protein levels in BMMs after LPS stimulation (P <0.01). CONCLUSION: Periodontal inflammation is associated with an enhancement of both the M1 and M2 phenotypes of macrophages, in which a phenotypic switch of M2 to M1 might be a critical mechanism in mediating periodontal tissue damage, including alveolar bone loss.

[Role of platelet-activating factor receptor in adhesion and invasion of Aggregatibacter actinomycetemcomitans in human umbilical vein endothelial cells].

OBJECTIVE: To explore the role of platelet-activating factor receptor (PAFR) in adhesion and invasion of phospho- rylcholine (PC)-positive Aggregatibacter actinomycetemcomitans in cultured human umbilical vein endothelial cells (HUVEC). METHDOS: Cultured HUVECs were pretreated with the PAFR antagonist CV3988 or anti-human PAFR monoclonal antibody for 30 min before infection with PC-positive or -negative A. actinomycetemcomitans strains. The bacterial adhesion and invasion and cytotoxicity in the cells were examined using MTT assay. RESULTS: Pretreatment with PAFR antagonists at 100, 200 and 500 nmol/L significantly reduced the adhesion rate (36.29∓3.52)%, (19.04∓3.35)% and (7.69∓3.19%), respectively] and invasion rate [(12.12∓1.58)%, (7.08∓0.29)% and (2.60∓2.26)%, respectively] of PC-positive A.actinomycetemcomitans in HUVECs. Similarly, pretreatment with anti-PAFR antibody also significantly reduced A.actinomycetemcomitans adhesion and invasion in HUVECs [(50.05∓5.28)% and (39.09∓6.50)%, respectively]. Pretreatment with PAFR antagonist (200 and 500 nmol/L) and anti-PAFR antibody (25 µg/mL) significantly increased the viability of HUVECs incubated with PC-positive A.actinomycetemcomitans from (25.39∓9.33)% to (91.12∓3.14)%, (94.12∓2.15)% and (65.5∓1.87)%, respectively, but such pretreatments did not increase the viability of cells incubated with PC-negative A.actinomycetemcomitans. CONCLUSIONS: PAFR plays an important role in the adhesion, invasion, and cytotoxicity of PC-positive A.actinomycetemcomitans in cultured HUVECs.

Epigenetic Modulation in Periodontitis: Interaction of Adiponectin and JMJD3-IRF4 Axis in Macrophages.

Emerging evidence suggests an important role for epigenetic mechanisms in modulating signals during macrophage polarization and inflammation. JMJD3, a JmjC family histone demethylase necessary for M2 polarization is also required for effective induction of multiple M1 genes by lipopolysaccharide (LPS). However, the effects of JMJD3 to inflammation in the context of obesity remains unknown. To address this deficiency, we firstly examined the expression of JMJD3 in macrophage isolated from bone marrow and adipose tissue of diet induced obesity (DIO) mice. The results indicated that JMJD3 was down-regulated in obesity. Adiponectin (APN), a factor secreted by adipose tissue which is down-regulated in obesity, functions to switch macrophage polarization from M1 to M2, thereby attenuating chronic inflammation. Intriguingly, our results indicated that APN contributed to JMJD3 up-regulation, reduced macrophage infiltration in obese adipose tissue, and abolished the up-regulation of JMJD3 in peritoneal macrophages isolated from DIO mice when challenged with Porphyromonas gingivalis LPS (pg.lps). To elucidate the interaction of APN and JMJD3 involved in macrophage transformation in the context of inflammation, we designed the loss and gain-function experiments of APN in vivo with APN(-/-) mice with experimental periodontitis and in vitro with macrophage isolated from APN(-/-) mice. For the first time, we found that APN can help to reduce periodontitis-related bone loss, modulate JMJD3 and IRF4 expression, and macrophage infiltration. Therefore, it can be inferred that APN may contribute to anti-inflammation macrophage polarization by regulating JMJD3 expression, which provides a basis for macrophage-centered epigenetic therapeutic strategies.

Changes in the hemolytic activity of Candida species by common electrolytes.

BACKGROUND: Hemolysins are crucial virulence factors which help pathogens to survive and persist in the host. This study investigated whether common electrolytes will affect the hemolysins of Candida species. The hemolysins from 25 Candida isolates were investigated using a plate specially designed for Candida species in the presence of three electrolytes, CaCl2, NaCl and KCl, at different concentrations. The hemolytic activity was determined after 48 h and the hemolytic index was calculated. RESULTS: All three electrolytes caused a decrease in the hemolytic activity. Significant differences existed between varying concentrations of NaCl, while no significant differences existed for the CaCl2 and KCl groups. Additionally, the peripheral hemolytic index was highly correlated with the hemolytic index (r = 0.656, p < 0.001). CONCLUSIONS: Our findings indicate that electrolytes reduce hemolysis by Candida species and a correlation exists between the peripheral hemolytic index and the translucent hemolytic index.

Epigenetically Modified Bone Marrow Stromal Cells in Silk Scaffolds Promote Craniofacial Bone Repair and Wound Healing.

Epigenetic regulation of gene expression is a central mechanism that governs cell stemness, determination, commitment, and differentiation. It has been recently found that PHF8, a major H4K20/H3K9 demethylase, plays a critical role in craniofacial and bone development. In this study, we hypothesize that PHF8 promotes osteoblastogenesis by epigenetically regulating the expression of a nuclear matrix protein, special AT-rich sequence-binding protein 2 (SATB2) that plays pivotal roles in skeletal patterning and osteoblast differentiation. Our results showed that expression levels of PHF8 and SATB2 in preosteoblasts and bone marrow stromal cells (BMSCs) increased simultaneously during osteogenic induction. Overexpressing PHF8 in these cells upregulated the expression of SATB2, Runx2, osterix, and bone matrix proteins. Conversely, knockdown of PHF8 reduced the expression of these genes. Furthermore, ChIP assays confirmed that PHF8 specifically bound to the transcription start site (TSS) of the SATB2 promoter, and the expression of H3K9me1 at the TSS region of SATB2 decreased in PHF8 overexpressed group. Implantation of the BMSCs overexpressing PHF8 with silk protein scaffolds promoted bone regeneration in critical-sized defects in mouse calvaria. Taken together, our results demonstrated that PHF8 epigenetically modulates SATB2 activity, triggering BMSCs osteogenic differentiation and facilitating bone formation and regeneration in biodegradable silk scaffolds.

Dental fear and its possible relationship with periodontal status in Chinese adults: a preliminary study.

BACKGROUND: The aim of the present study was to describe the characteristics of dental fear of Chinese adult patients with periodontal disease and provide information for clinical assessment. METHODS: A total of 1203 dental patients completed questionnaires that included Corach's Dental Anxiety Scales (DAS), Dental Fear Survey (DFS) and the short-form Dental Anxiety Inventory (S-DAI). Among all the patients, 366 cases were self-reported periodontal disease. The general characteristics were described, such as socio-demographics, dental attendances and oral health behaviors. The statistical analysis was performed by t-test, Mann-Whitney U test and linear regression respectively to evaluate correlations between dental fear and general characteristics according to the three scales. RESULTS: The prevalence of dental fear was 74% among 1203 patients, 23.4% of total with high dental fear, while 27.3% in the patients with periodontal disease. The average score of DAS and DFS for patients with periodontal disease was significantly higher than those without periodontal disease. The regression analysis indicated that gender, age, periodontal status, dental attendances and oral health behaviors were correlated with dental fear. Among 366 patients with periodontal disease, gender, dental attendances and oral health behaviors had correlation with dental fear. The analysis of DFS scale exhibited that 'drilling with handpiece' and 'injecting the anesthetic' were the most important factors to contribute to dental fear. CONCLUSIONS: There was high prevalence of dental fear in Chinese adult patients, particularly in patients with periodontal disease, and high level of dental fear may lead to poor periodontal status.

Hyperglucose contributes to periodontitis: involvement of the NLRP3 pathway by engaging the innate immunity of oral gingival epithelium.

BACKGROUND: The NLRP3 inflammasome is essentially a family of intracellular innate immune sensors that can respond to bacterial challenge and initiate early host immunity responses. However, the involvement and possible molecular mechanism of the NLRP3 pathway in the context of chronic periodontitis (CP) and diabetes mellitus have yet to be fully elucidated. METHODS: Gingival tissues were collected from patients with CP and/or type 2 diabetes mellitus (T2DM), and the expression of NLRP3 and interleukin (IL)-1ß was analyzed by immunohistochemistry. To explore the possible molecular mechanism, human gingival epithelial cells (HGECs) were established in vitro and challenged with lipopolysaccharide (LPS) and/or high glucose. High extracellular K(+) was applied as an inhibitor of NLRP3. The NLRP3 pathway was analyzed by immunocytochemistry and quantitative polymerase chain reaction. RESULTS: Compared with control individuals, NLRP3 and IL-1ß were significantly upregulated in oral gingival epithelium of patients with CP and/or T2DM (P <0.05). The expression of NLRP3 was significantly upregulated in HGECs when stimulated in vitro by LPS or high glucose (P = 0.00). The simultaneous stimulation of LPS and high glucose contributed to significant upregulation of NLRP3 expression versus LPS or high glucose alone (P = 0.00). Although expression of caspase 1 and IL-1ß protein were increased in HGECs when stimulated by LPS, they were partially inhibited after the NLRP3 was successfully blocked. CONCLUSION: For patients with T2DM and CP, hyperglycemic status may exacerbate the inflammation state of gingival tissue by activating the NLRP3 pathway, and this abnormal host inflammatory response may contribute to further tissue breakdown.

Adiponectin regulates bone marrow mesenchymal stem cell niche through a unique signal transduction pathway: an approach for treating bone disease in diabetes.

Adiponectin (APN) is an adipocyte-secreted adipokine that exerts well-characterized antidiabetic properties. Patients with type 2 diabetes (T2D) are characterized by reduced APN levels in circulation and impaired stem cell and progenitor cell mobilization from the bone marrow for tissue repair and remodeling. In this study, we found that APN regulates the mobilization and recruitment of bone marrow-derived mesenchymal stem cells (BMSCs) to participate in tissue repair and regeneration. APN facilitated BMSCs migrating from the bone marrow into the circulation to regenerate bone by regulating stromal cell-derived factor (SDF)-1 in a mouse bone defect model. More importantly, we found that systemic APN infusion ameliorated diabetic mobilopathy of BMSCs, lowered glucose concentration, and promoted bone regeneration in diet-induced obesity mice. In vitro studies allowed us to identify Smad1/5/8 as a novel signaling mediator of APN receptor (AdipoR)-1 in BMSCs and osteoblasts. APN stimulation of MC3T3-E1 osteoblastic cells led to Smad1/5/8 phosphorylation and nuclear localization and increased SDF-1 mRNA expression. Although APN-mediated phosphorylation of Smad1/5/8 occurred independently from adaptor protein, phosphotyrosine interaction, pleckstrin homology domain, and leucine zipper containing 1, it correlated with the disassembly of protein kinase casein kinase 2 and AdipoR1 in immunoprecipitation experiments. Taken together, this study identified APN as a regulator of BMSCs migration in response to bone injury. Therefore, our findings suggest APN signaling could be a potential therapeutic target to improve bone regeneration and homeostasis, especially in obese and T2D patients.

Knowledge, awareness, and behaviors of endocrinologists and dentists for the relationship between diabetes and periodontitis.

AIMS: This study aimed to compare the opinions of dentists and endocrinologists regarding diabetes mellitus (DM) and periodontitis, and to investigate the possible effects on their practice. METHODS: Cross-sectional data were collected from 297 endocrinologists and 134 dentists practicing in southern China using two separated questionnaires. Questions were close-ended or Likert-scaled. Statistical analyses were done by descriptive statistics, bivariate and binary logistic regression analysis. RESULTS: Compared with endocrinologists, dentists presented more favorable attitudes for the relationship of DM and periodontitis (P<0.001). 61.2% of dentists reported they would frequently refer patients with severe periodontitis for DM evaluation, while only 26.6% of endocrinologists reported they would frequently advise patients with DM to visit a dentist. Nearly all of the respondents (94.4%) agreed that the interdisciplinary collaboration should be strengthened. The logistic regression analysis exhibited that respondents with more favorable attitudes were more likely to advise a dental visit (P=0.003) or to screen for DM (P=0.006). CONCLUSIONS: Endocrinologists and dentists are not equally equipped with the knowledge about the relationship between DM and periodontitis, and there is a wide gap between their practice and the current evidence, especially for endocrinologists. It's urgent to take measures to develop the interdisciplinary education and collaboration among the health care providers.

Toll-like receptor 4-mediated hyper-responsiveness of gingival epithelial cells to lipopolysaccharide in high-glucose environments.

BACKGROUND: Increasing evidence indicates that diabetes mellitus increases the incidence and severity of periodontitis. Toll-like receptors (TLRs) play a role in the pathogenic processes of diabetes and its complications, but the effect of high glucose on TLRs in patients with diabetes and periodontitis is still unclear. METHODS: Two kinds of diabetes rat models were established. Human gingival epithelial cells (HGECs) were established and challenged with Porphyromonas gingivalis lipopolysaccharide (LPS) in the context of high glucose in vitro. The expressions of TLR2 and TLR4 were detected using immunohistochemistry, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and flow cytometry. The TLR4 inhibitor ethyl (6R)-6-[(2-chloro-4-fluorophenyl)sulfamoyl]cyclohexene-1-carboxylate (TAK-242) was applied to block the TLR4 in HGECs, and the inflammatory factors were detected by qRT-PCR. RESULTS: The expression of TLR2 and TLR4 in gingival tissue from both rat diabetes models was significantly increased compared with that of healthy controls. Moreover, TLR4 expression was also markedly increased in HGECs incubated with high glucose. The expression of interleukin (IL)-6, IL-8, and monocyte chemoattractant protein-1 were significantly increased in HGECs while challenged with LPS in the context of high glucose; however, the expression inflammatory cytokines were decreased significantly, whereas TLR4 was blocked by TAK-242. CONCLUSION: High glucose contributes to an upregulated expression of TLR4 in gingival epithelium, and TLR4-dependent inflammatory response may promote the susceptibility to periodontitis in patients with diabetes.

[Effects of non-surgical periodontal treatment on clinical response, serum inflammatory parameters, and metabolic control of type 2 diabetes patients with moderate to severe periodontitis].

OBJECTIVE: To evaluate the effects of periodontal treatment on the clinical response, systemic inflammatory parameters, and metabolic control of type 2 diabetes patients with moderate to severe periodontitis. METHODS: A total of 56 patients with mean clinical attachment level (CAL)>3 mm were included in the subgroup analysis. A repeated-measures ANOVA (group factor: treatment group and control group; time factor: initial visit, 1.5, 3, and 6 months) was used to analyze the probing depth (PD), CAL, bleeding on probing (BOP), high-sensitivity C-reactive protein (hsCRP), glycated hemoglobin (HbA1c), and fasting plasma glucose. RESULTS: Significantly lower PD (F=62.898, P-0.000), CAL (F=51.263, P-0.000), BOP (F=75.164, P=0.000), hsCRP (F=6.391, P=0.010), HbA1c(F=4.536, P=0.011), and fasting plasma glucose level (F= 3.073, P=0.031) were observed after therapeutic periodontal improvement. The inter-group differences for PD (t=-2.050, P=0.045), BOP (t=-4.538, P=0.000), and hsCRP (t=-2.261, P=0.028) were statistically significant after therapy. CONCLUSION: Non-surgical periodontal treatment can effectively improve periodontal status, circulating inflammatory status, and metabolic control of diabetic patients with moderate to severe periodontitis.

Long-term follow-up evaluation of an acatalasemia boy with severe periodontitis.

BACKGROUND: Acatalasemia is a rare genetic catalase deficiency that is inherited as an autosomal recessive trait. Although usually asymptomatic, a syndrome of oral ulcerations and gangrene may be present (Takahara's disease). In this report, we presented the diagnosis and 15-y periodontal treatments of an acatalasemia patient with Takahara's disease in China. METHODS: To confirm the diagnosis of acatalasemia, intron 4 of the catalase gene was amplified and sequenced. Erythrocyte catalase activity was measured by ultraviolet spectrophotometer. Besides, periodontal treatments and 15y follow-up were performed. RESULTS: Direct sequencing showed a clear splicing mutation of guanine to adenine substitution at the fifth position of intron 4 in the patient. Erythrocyte catalase activity of the patient (5.2MU/l, 4.6%) was 10% lower than the normal range (113.3±16.5MU/l). After 15-y treatments, the periodontal pocket depth ≥4mm and clinical attachment loss reduced to 30% and 3.7±1.2mm. CONCLUSIONS: Based on these findings, a diagnosis of acatalasemia was established. And the periodontal therapies have achieved a stable periodontal status.

Effect and possible mechanism of network between microRNAs and RUNX2 gene on human dental follicle cells.

To investigate whether crosstalk between RUNX2 and miRNAs is involved in tooth eruption regulated by dental follicle cells (DFCs) and the possible molecular mechanism. Blood samples and embedded dental follicles were collected from patients with cleidocranial dysplasia, and RUNX2 gene mutations were analyzed, then RUNX2(+/m) DFCs were isolated and identified. The characteristics of RUNX2(+/m) DFCs were analyzed. The differential expression of miRNAs was detected between the RUNX2(+/m) DFCs and RUNX2(+/+) DFCs by microarray, and target genes were predicted by miRGen. miR-146a was chosen for further investigation, and its effects in DFCs were analyzed by transfecting its mimics and inhibitors, and expression of genes involved in tooth eruption were detected. A novel insertion mutation (c.309_310insTG) of RUNX2 gene was identified which had an effect on the characteristics of DFCs. Compared with the RUNX2(+/+) DFCs, there were 69 microRNAs more than twofold up-regulated and 54 microRNAs more than twofold down-regulated in the RUNX2(+/m) DFCs. Among these, miR-146a decreased significantly in RUNX2(+/m) DFCs, and expression of RUNX2, CSF-1, EGFR, and OPG was significantly altered when miR-146a was overexpressed or inhibited. RUNX2 gene mutation contributes to the characteristic change of DFCs, and the crosstalk between RUNX2 gene and miRNAs may be one of the key regulatory mechanisms of differentiation of DFCs.