Baicalein inhibits IL-1ß-induced extracellular matrix degradation with decreased MCP-1 expression in primary rat chondrocytes.

Baicalein is a flavonoid extracted from the roots of Scutellaria baicalensis and Scutellaria lateriflora. This compound exerts various biochemical activities, including antioxidant and anti-inflammatory effects. The study aimed to investigate the effect of baicalein on articular cartilage cells and elucidate its underlying mechanism. In primary rat chondrocyte cultures, treatment with baicalein demonstrated a reduction in the loss of proteoglycan and extracellular matrix degradation induced by interleukin (IL)-1ß. Baicalein suppressed IL-1ß-induced catabolic responses, including the expression and activation of matrix metalloproteinase (MMP)-13, MMP-3, and MMP-1. In addition, baicalein effectively reduced nitric oxide and prostaglandin E2 production, and it downregulated the expression of inducible nitric oxide synthase and cyclooxygenase-2 in primary rat chondrocytes. Furthermore, baicalein downregulated IL-1ß-induced inflammatory chemokines and cytokines, such as GM-CSF and MCP-1. These findings suggest that baicalein could potentially mitigate the catabolic responses of IL-1ß in chondrocytes, making it a promising candidate for both the prevention and treatment of osteoarthritis. Supplementary Information: The online version contains supplementary material available at 10.1007/s43188-024-00225-4.

Association between birth-related factors and periodontitis in women: Korea National Health and Nutrition Examination Survey 2013-2018.

AIM: Adult women experience several changes in physiological status, such as pregnancy and childbirth, during their life cycle. This study analyses the association between birth-related factors (the number of childbirths, abortions and miscarriages) and periodontitis using data from the Korea National Health and Nutrition Examination Survey, which represents Korean adults. MATERIALS AND METHODS: The study used data from Korea National Health and Nutrition Examination Survey VI and VII (2013-2018) and included 10,072 women 19 years or older, with no missing data on the variables assessed. Periodontitis was defined according to the Community Periodontal Index (CPI) criteria. Multiple logistic regression analysis, adjusting for age, household income, education, alcohol consumption, smoking, stress, body mass index, waist circumference, hypertension, diabetes mellitus, an oral examination within 1 year, daily tooth brushing frequency, hygiene products and self-perceived oral health as identified via logistic regression analyses, was performed to determine the association between birth-related variables and periodontitis. RESULTS: In the crude model, the odds ratio (OR) showed a significantly increased risk of periodontitis (CPI ≥ 3) and severe periodontitis (CPI = 4) based on the number of childbirths, abortions and miscarriages (p < .05). After covariate adjustment, periodontitis (CPI ≥ 3) was associated with the number of childbirths (1: OR = 1.92; 95% confidence interval [CI]: 1.47-2.50; 2: OR = 2.03; 95% CI: 1.57-2.61; ≥3: OR = 2.11; 95% CI: 1.60-2.78). Furthermore, severe periodontitis (CPI = 4) was also associated with the number of childbirths (1: OR = 2.33; 95% CI: 1.24-4.38; 2: OR = 2.99; 95% CI: 1.62-5.52; ≥3: OR = 3.34; 95% CI: 1.79-6.21). CONCLUSIONS: The findings of this large-scale, nationally representative study suggest that the number of childbirths is associated with the severity of periodontitis. However, the relationship between the number of abortions and miscarriages and periodontitis (CPI ≥ 3) or severe periodontitis (CPI = 4) is not significant.

Prevention of Dental Erosion Caused by Fermented Milk: An In-vitro Study.

PURPOSE: This study aimed to assess the efficacy of three techniques for preventing dental erosion and thereby identify effective methods. The three techniques were: 1) adding calcium to fermented milk (2% Ca and 0.5% Ca); 2) topical application of fluoride to the teeth before exposure to fermented milk (acidulated phosphate fluoride [APF] gel and 0.05% NaF); and 3) a combination of the two techniques (APF gel + 0.5% Ca, 0.05% NaF + 0.5% Ca). MATERIALS AND METHODS: pH cycling was performed on bovine-tooth specimens alternately immersed in experimental solutions and artificial saliva. After treatment, the microhardness and roughness of the enamel surfaces were measured, and changes in the surface morphology were observed using atomic force microscope images. RESULTS: Microhardness did not differ statistically significantly between the 2% Ca and mineral water (negative control) groups (2% Ca: 295.34 ± 11.50; mineral water group: 294.76 ± 10.67; p > 0.05). Surface roughness did not differ statistically significantly between the 2% Ca, 0.05% NaF + 0.5% Ca, and mineral water groups (2% Ca: 16.81 ± 7.23; 0.05% NaF + 0.5% Ca: 15.77 ± 2.86; mineral water group: 13.35 ± 5.53; p > 0.05). The surface morphology did not change in the mineral water and 2% Ca groups. CONCLUSION: Considering that 2% calcium is a high concentration, adding a low concentration of calcium to fermented milk and applying a low concentration of fluoride daily decreased the reduction of surface microhardness and reduced the increase in surface roughness without causing marked changes in surface morphology. This confirms that combining the two techniques is an effective strategy to prevent dental erosion in-vitro.

Association between Present Teeth and Muscle Strength in Older People in Korea.

BACKGROUND: As the world population continues to age, interest in muscle strength loss in older people is increasing. This study aimed to confirm the association between present teeth and muscle strength in older people in Korea. METHODS: Using data extracted from the 2014-2019 Korea National Health and Nutrition Examination Survey, we analyzed 5136 older people aged 65-79 years. The present teeth were based on 20 teeth, which is the criteria for comfortable mastication. The association of the risk of low muscle strength according to the present teeth was assessed using multiple logistic regression analysis, and the association was confirmed by dividing into subgroups according to sex. RESULTS: The prevalence of low muscle strength was 17.87% among all participants. Multiple logistic regression analysis confirmed the association between low muscle strength and present teeth; a significant association was found even in the model in which all covariates were adjusted (odds ratios (OR) = 1.35; 95% confidence interval (CI): 1.13-1.61). Subgroup analysis revealed a significant association between present teeth and low muscle strength even in the model in which both covariates were adjusted for sex (Men, OR = 1.41; 95% CI: 1.02-1.95; Women, OR = 1.31; 95% CI: 1.06-1.6). CONCLUSION: An association between present teeth and low muscle strength was confirmed in older people in Korea. These results indicate that the importance of oral hygiene management should be emphasized to prevent muscle strength loss in older people.

Association between Oral Health Status and Relative Handgrip Strength in 11,337 Korean.

Grip strength is a simple indicator of physical strength and is closely associated with systemic health. Conversely, oral health has also been reported to have an important association with systemic health. The present study aimed to assess the effect of oral health status on relative handgrip strength. The data pertaining to 11,337 participants were obtained by means of the seventh Korea National Health and Nutrition Survey (2016 to 2018). Oral health status was evaluated on the basis of the presence of periodontitis and number of remaining teeth (PT, present teeth). Relative handgrip strength was evaluated by means of a digital dynamometer and the value pertaining to the lower 25% of measurements was used as the quartile by gender. The association between oral health status and relative handgrip strength was evaluated by means of multiple regression analysis and multiple logistic regression analysis with covariate correction. Analysis of the crude model revealed a significant association in the group of patients with periodontal disease (odds ratio = 1.69, 95% confidence interval: 1.51-1.89). However, analysis with adjusted covariates revealed that the association was not statistically significant. Moreover, statistical analysis after adjustment for covariates revealed a consistent correlation between PT and relative handgrip strength as categorical and continuous variables. Hence, the present study observed a significant association between oral health status and relative handgrip strength among the Korean adult population.

No Association between Metabolic Syndrome and Periodontitis in Korean Postmenopausal Women.

This study aimed to determine the association between metabolic syndrome (MetS) and periodontitis in Korean postmenopausal women. The study selected 3320 menopause women (40-79-year-old) from those who participated in the seventh Korea National Health and Nutrition Survey (2016-2018). This association was determined using frequency and multiple logistic regression analyses. The prevalence of MetS in postmenopausal women was 33.2%, and among the MetS components, abdominal obesity showed a higher odds ratio of periodontitis by 1.36 (95% confidence interval (CI): 1.12-1.65; p < 0.05). The odds ratio for periodontitis was 1.34 times higher (95% CI: 1.12-1.60) in the MetS prevalence group with three or more MetS components (p < 0.05); however, after adjusting for demographic characteristics and health behavior variables, it was not statistically significant. Therefore, our results indicated that MetS has no association with periodontitis in postmenopausal women after adjusting for confounding variables.

Association between Metabolic Syndrome and the Number of Remaining Teeth in Postmenopausal Women: A Cross-Sectional Analysis Using the Korean National Health and Nutritional Examination Survey.

There are very few studies on metabolic syndrome (MetS) and oral health in postmenopausal women. The purpose of this cross-sectional study was to determine the association between MetS and its components and the number of remaining teeth in postmenopausal women in Korea. The study selected 3320 menopausal women (40-79 years old) from those who participated in the seventh Korea National Health and Nutrition Survey (2016-2018). Multiple regression and multiple logistic regression analyses were performed to determine the association between MetS and its components and the number of remaining teeth. According to the multiple regression analysis, the regression coefficient (B) values were -1.62 (p < 0.05), -1.31 (p < 0.05), -1.60 (p < 0.05), and -2.28 (p < 0.05) in the hypertension group, hyperglycemia group, low high-density lipoprotein (HDL) cholesterol group, and MetS prevalence group, respectively. This indicates that the number of remaining teeth was lower in the MetS prevalence group as compared to the non-prevalence groups. As observed in the multiple logistic regression analysis, the odds ratio of the number of remaining teeth (less than 20) was higher in the MetS prevalence group (1.82 (p < 0.05)) as compared to the non-prevalence groups (1.25 (p < 0.05) in the abdominal obesity group, 1.50 (p < 0.05) in the hypertension group, 1.36 (p <0.05) in the hyperglycemia group, and 1.72 (p < 0.05) in the low HDL cholesterol group). Therefore, our results indicate that abdominal obesity, hypertension, diabetes, dyslipidemia, and prevalence of MetS are associated with tooth loss in postmenopausal women.

Litsea japonica Leaf Extract Suppresses Proinflammatory Cytokine Production in Periodontal Ligament Fibroblasts Stimulated with Oral Pathogenic Bacteria or Interleukin-1ß.

Periodontal disease, a chronic disease caused by bacterial infection, eventually progresses to severe inflammation and bone loss. Regulating excessive inflammation of inflamed periodontal tissues is critical in treating periodontal diseases. The periodontal ligament (PDL) is primarily a connective tissue attachment between the root and alveolar bone. PDL fibroblasts (PDLFs) produce pro-inflammatory cytokines in response to bacterial infection, which could further adversely affect the tissue and cause bone loss. In this study, we determined the ability of Litsea japonica leaf extract (LJLE) to inhibit pro-inflammatory cytokine production in PDLFs in response to various stimulants. First, we found that LJLE treatment reduced lipopolysaccharide (LPS)-induced pro-inflammatory cytokine (interleukin-6 and interleukin-8) mRNA and protein expression in PDLFs without cytotoxicity. Next, we observed the anti-inflammatory effect of LJLE in PDLFs after infection with various oral bacteria, including Fusobacterium nucleatum, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. These anti-inflammatory effects of LJLE were dose-dependent, and the extract was effective following both pretreatment and posttreatment. Moreover, we found that LJLE suppressed the effect of interleukin-1 beta-induced pro-inflammatory cytokine production in PDLFs. Taken together, these results indicate that LJLE has anti-inflammatory activity that could be exploited to prevent and treat human periodontitis by controlling inflammation.

Anti-inflammatory effects of bamboo salt and sodium fluoride in human gingival fibroblasts--An in vitro study.

Dental caries preventive agents, such as sodium fluoride (NaF) and bamboo salt (BS), are known to cause cellular growth that is characterized by morphological and gene expression changes. This study was designed to investigate the dual effect of NaF and BS on interleukin (IL)-1ß-induced gingival inflammation. Under in vitro experimental conditions, exposure to a subcytotoxic dose of IL-1ß enhanced human gingival fibroblast inflammation, as characterized by increased levels of inflammation-associated proteins. A combination of NaF and BS significantly protected fibroblasts from IL-1ß-induced cellular deterioration. Exposure to NaF and BS induced the cell growth and no changes in viability were found with the Lactate Dehydrogenase Assay (LDH) assay at the NaF and BS concentration analyzed. Molecular analysis demonstrated that NaF and BS increased resistance to inflammation by reduction of IL-1ß, IL-8, and tumor necrosis factor (TNF)-α production. In addition, NaF and BS decreased the expression of IL-1ß, IL-8, and TNF-α mRNA in IL-1ß-induced human gingival fibroblast cells. The study identifies a new role for NaF and BS in the IL-1ß-induced inflammation of gingival fibroblasts and provides a potential target for gingival protection.

Chlorhexidine-releasing orthodontic elastomerics.

The aim of this study was to identify the best combination of chlorhexidine (CHX) with orthodontic elastomerics for prevention of oral disease in orthodontic patients. We used ethyl cellulose (EC) as the polymer, and experimental groups were divided into five groups according to differences in solvent (i.e., ethanol; EtOH, dichloromethane; DCM). CHX release from the coated elastomerics was evaluated with a UV spectrophotometer and observed by scanning electron microscope (SEM). The antimicrobial release increased over time for 48 h in Group 3 (CDA+EC+30% EtOH/70% DCM), exhibiting the longest sustained-release characteristics (p<0.001). It also showed the highest antimicrobial properties, which was confirmed by inhibition zone testing using S. mutans (p<0.05). All groups were not affected when tensile force was tested in the coated elastomerics. We conclude that the antibacterial effect of CHX can be adjusted according to combinations of polymers and solvents. Group 3 exhibited the best substantivity and antimicrobial properties.

Screening and development of DNA aptamers specific to several oral pathogens.

Aptamers are composed of single-stranded oilgonucleotides that can selectively bind desired molecules. It has been reported that RNA or DNA could act as not only a genetic messenger but also a catalyst in metabolic pathways. RNA aptamers (average sizes 40-50 bp) are smaller than antibodies and have strong binding capacities to target molecules, similar to antigen-antibody interactions. Once an aptamer was selected, it can be readily produced in large quantities at low cost. The objectives of this study are to screen and develop aptamers specific to oral pathogens such as Porphyromonas gingivalis, Treponema denticola, and Streptococcus mutans. The bacterial cell pellet was fixed with formaldehyde as a target molecule for the screening of aptamers. The SELEX method was used for the screening of aptamers and a modified western blot analysis was used to verify their specificities. Through SELEX, 40 kinds of aptamers were selected and the specificity of the aptamers to the bacterial cells was confirmed by modified western blot analysis. Through the SELEX method, 40 aptamers that specifically bind to oral pathogens were screened and isolated. The aptamers showed possibility as effective candidates for the detection agents of oral infections.

Estimation of fluoride intake from milk-based infant formulas and baby foods.

The aim of this study was to examine the amount of fluoride ingested from infant formula and baby food in infants aged up to 6 months in South Korea. The fluoride content of 20 commercially available formulas and 8 baby food samples from 4 different brands was measured using a modified microdiffusion method and fluoride ion selective electrode. The amount of fluoride (F) ingested by infants was estimated assuming that the samples were reconstituted with water containing 0, 0.5, 0.8, and 1.0 ppm F. When the reconstituted formulas and baby foods contained 0.8 ppm F water, the infants were estimated to ingest fluoride in the range of 0.018 to 0.298 mg/kg/day. The findings of this study suggest that there is a need for clear guidelines for fluoride consumption by infants that should be followed by manufacturers and parents.

Effects of mineral trioxide aggregate mixed with hydration accelerators on osteoblastic differentiation.

INTRODUCTION: Despite good physical and biological properties, mineral trioxide aggregate (MTA) has a long setting time. A hydration accelerator could decrease the setting time of MTA. This study assessed the biocompatibility of MTA mixed with hydration accelerators (calcium chloride and low-dose citric acid) and investigated the effect of these materials on osteoblast differentiation. METHODS: Cell viability was evaluated by the EZ-Cytox assay kit (Daeil Lab Service, Seoul, Korea). The gene expressions of osteocalcin and bone sialoprotein were detected by reverse-transcription polymerase chain reaction and real-time polymerase chain reaction. The mineralization behavior was evaluated with alizarin red staining. RESULTS: There was no statistically significant difference in cell viability between experimental groups. The messenger RNA level of osteogenic genes significantly increased in MTA mixed with hydration accelerators compared with the control and MTA mixed with water. MTA mixed with the hydration accelerators resulted in similar mineralization compared with MTA mixed with water. CONCLUSIONS: Hydration accelerators increase the osteogenic effect and show a similar effect on the mineralization of MTA, which may have clinical applications.

Effect of bamboo salt-NaF dentifrice on enamel remineralization.

PURPOSE: To evaluate the laboratory remineralization effects of a dentifrice with bamboo salt and NaF on artificial caries-like enamel lesions, at both the surface and deep areas. METHODS: Early dental caries lesions were formed by treating bovine enamel samples for 48 hours at 37 degrees C with a demineralization solution (pH 5.0) containing 0.1 M lactic acid, 0.2% Carbopol 907, and 50% saturated calcium phosphate tribasic. pH cycling was then performed by immersing the samples in dentifrice slurry for 2 minutes every 8 hours per day, and in demineralization solution for 4 hours and mixed saliva for the remaining time period. The mixed saliva consisted of 50% human saliva and 50% artificial saliva. The surface hardness and the level of mineral surface alterations were analyzed using a hardness tester and transversal microradiography, among negative control (fluoride free), positive control (sodium fluoride 1100 ppm, Crest Cavity Protection), and test dentifrice (3.0% bamboo salt with sodium fluoride 1,000 ppm) groups. RESULTS: Test and positive control groups significantly increased the level of the surface hardness and decreased mineral loss of the artificial caries-like enamel lesions compared to the negative control (P<0.05). The test dentifrice also significantly decreased the lesion depth compared to the other two groups (P<0.05).

Inhibitory effect of methyl gallate and gallic acid on oral bacteria.

This study examined the ability of methyl gallate (MG) and gallic acid (GA), the main compounds of gallo-tannins in Galla Rhois, to inhibit the proliferation of oral bacterial and the in vitro formation of Streptococcus mutans biofilms. The antimicrobial activities of these compounds were evaluated in vitro using the broth microdilution method and a beaker-wire test. Both MG and GA had inhibitory effects on the growth of cariogenic (MIC<8 mg/ml) and periodontopathic bacteria (MIC=1 mg/ml). Moreover, these compounds significantly inhibited the in vitro formation of S. mutans biofilms (MG, 1 mg/ml; GA, 4 mg/ml; P<0.05). MG was more effective in inhibiting bacterial growth and the formation of S. mutans biofilm than GA. In conclusion, MG and GA can inhibit the growth of oral pathogens and S. mutans biofilm formation, and may be used to prevent the formation of oral biofilms.