Hesperetin inhibits neuroinflammation on microglia by suppressing inflammatory cytokines and MAPK pathways.

Neuroinflammation is a specific or nonspecific immunological reaction in the central nervous system that is induced by microglia activation. Appropriate regulation of activated microglial cells is therefore important for inhibiting neuroinflammation. Hesperetin is a natural flavanone and an aglycone of hesperidin that is found in citrus fruits. Hesperetin reportedly possesses anti-inflammatory, anti-cancer, and antioxidant effects. However, the anti-neuroinflammatory effects of hesperetin on microglia are still unknown. Here, we investigated the anti-neuroinflammatory effects of hesperetin on lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. We found that hesperetin strongly inhibited nitric oxide production and expression of inducible nitric oxide synthase in LPS-stimulated BV-2 microglial cells. Hesperetin also significantly reduced secretion of inflammatory cytokines including interleukin (IL)-1ß and IL-6. Furthermore, hesperetin down-regulated the phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and p38 mitogen-activated protein kinase, exerting anti-inflammatory effects. Hesperetin suppressed astrocyte and microglia activation in the LPS-challenged mouse brain. Collectively, our findings indicate that hesperetin inhibits microglia-mediated neuroinflammation and could be a prophylactic treatment for neurodegenerative diseases.

Anti-Neuroinflammatory Effects of Vanillin Through the Regulation of Inflammatory Factors and NF-κB Signaling in LPS-Stimulated Microglia.

Microglia, resident macrophages of the central nervous system (CNS), is responsible for immune responses and homeostasis of the CNS. Microglia plays a complex role in neuroinflammation, which has been implicated in neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Therefore, therapeutic agents that suppress the microglia-mediated inflammatory response could potentially be used in the prevention or treatment of neurodegenerative diseases. Vanillin, a primary component of vanilla bean extract, has anti-inflammatory, anticancer, and antitumor properties. However, the effects of vanillin on the anti-neuroinflammatory responses of microglial cells are still poorly understood. In this study, we investigated the mechanism by which vanillin induces anti-neuroinflammatory responses in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. We found that vanillin significantly decreased the production of nitric oxide and pro-inflammatory cytokines, including interleukin (IL)-1ß, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). Vanillin also reduced the protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), as well as the mRNA expression levels of IL-1ß, TNF-α, and IL-6. Moreover, vanillin inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear factor (NF)-κB. Collectively, these results suggest that vanillin has anti-neuroinflammatory properties and may act as a natural therapeutic agent for neuroinflammatory diseases.

Antimicrobial effect against oral bacteria on bioactive compounds in a high-pressure enzymatic Prunus mume extract / Efeito antimicrobiano contra bactérias orais sobre compostos bioativos em um extrato enzimático de Prunus mume de alta pressão

To evaluate high-pressure processing combined with enzymatic treatment for extraction of Prunus mume by determining the optimum extraction conditions for the antimicrobial activity against oral bacteria. Highpressure enzymatic extraction was used to isolate biologically active components from P. mume. The effects of process variables such as enzyme type (Pectinex Ultra SP-L, Novozym 33095 and Viscozyme L), enzyme concentration, incubation time/temperature, pH, and ratio of enzymes antimicrobial activity against oral pathogens related to dental caries and periodontal diseases were determined by disk diffusion assay. The optimal conditions for enzymatic extraction from P. mume were pH 6.0, 45°C, 20 h, and 5 v/v% with Pectinex Ultra SP-L. The maximum antimicrobial activity of P. mume extract obtained using Novozym 33095 was at pH 7.0, 45°C, 20 h, and 5 v/v%. The Viscozyme L extract showed the maximum inhibitory effect at pH 6.0, 45°C, 20 h, and 5 v/v%. Use of combinations of enzymes did not result in significantly different antimicrobial activity (p < 0.05) compared with each enzyme alone. Minimum inhibitory concentration values were 3.125 to 12.50%. These results indicated that high-pressure enzymatic extraction yielded P. mume extract with antimicrobial activity which has the potential for improving oral environment.

Avaliar o processamento de alta pressão combinado com o tratamento enzimático para a extração de Prunus mume, determinando as condições ótimas de extração para a atividade antimicrobiana contra as bactérias orais. A extração enzimática de alta pressão foi utilizada para isolar os componentes biologicamente ativos de P. mume. Os efeitos das variáveis do processo como o tipo enzimático (Pectinex Ultra SP-L, Novozym 33095 e Viscozyme L), a concentração de enzima, o tempo/temperatura de incubação, pH, e a relação da atividade antimicrobiana de enzimas contra os patógenos orais relacionados à cárie dentária e doenças periodontais foram determinados pelo ensaio de difusão em disco. As condições ótimas para a extração enzimática de P. mume foram pH 6.0, 45°C, 20 h, e 5 v/v% com Pectinex Ultra SP-L. A máxima atividade antimicrobiana do extrato de P. mume obtida usando Novozym 33095 foi em pH 7.0, 45°C, 20 h, e 5 v/v%. O extrato de Viscozyme L apresentou o efeito inibitório máximo em pH 6.0, 45°C, 20 h, e 5 v/v%. O uso de combinações de enzimas não resultou em uma atividade antimicrobiana significativamente diferente (p < 0.05) em comparação com cada enzima por separada. Os valores mínimos da concentração inibitória foram de 3.125 a 12.50%. Estes resultados indicaram que a extração enzimática de alta pressão produziu o extrato de P. mume com atividade antimicrobiana,o qual tem o potencial para melhorar o ambiente bucal.

Tooth wear and cleaning effect of an abrasive-free dentifrice.

BACKGROUND/PURPOSE: To evaluate the degree of wear on human teeth and the cleaning effect of abrasive-free dentifrice. A sodium pyrophosphate and cellulose-containing abrasive-free dentifrice and calcium carbonate-containing control dentifrice were evaluated. MATERIALS AND METHODS: Dentin and enamel specimens were subjected to 109,500 successive double strokes and 5480 double strokes in pH-cycling condition. A profilometer measured abrasion depth. The cleaning effect of dentifrices on artificial stain was evaluated by cleaning power (modified Stookey method) and by removal of colored stain on artificial tooth. RESULTS: The experimental results were evaluated using Mann-Whitney U test. The abrasion depth in dentin specimens was 13.97-26.73 times smaller with abrasive-free dentifrice than with control dentifrice. The abrasion depth of enamel specimen was 2.17 ± 0.66 µm with control dentifrice. The values for abrasive-free dentifrice were too small to measure. In pH-cycling conditions using dentin specimens, abrasion depth was 14.28-19.00 times smaller with abrasive-free dentifrice than with control dentifrice. The cleaning power and removing effect of colored stain were statistically insignificant between abrasive-free dentifrice and control dentifrice (P > 0.05). CONCLUSION: The abrasive-free dentifrice was as effective as control dentifrice in its cleaning effect on artificial stain and can significantly reduce tooth wear more than control dentifrice.

Bone-forming peptide-3 induces osteogenic differentiation of bone marrow stromal cells via regulation of the ERK1/2 and Smad1/5/8 pathways.

A bone-remodeling imbalance induced by increased bone resorption and osteoclast formation causes skeletal diseases such as osteoporosis. Induction of osteogenic differentiation of bone marrow stromal cells (BMSCs) leads to bone regeneration. Many researchers have tried to develop new adjuvants as specific stimulators of bone regeneration for therapeutic use in patients with bone resorption. We tried to develop a new adjuvant that has stronger osteogenic differentiation-promoting activity than bone morphogenetic proteins (BMPs). In this study, we identified a new peptide, which we called bone-forming peptide (BFP)-3, derived from the immature precursor of BMP-7. Upon osteogenic differentiation, BMSCs treated with BFP-3 exhibited higher alkaline phosphatase (ALP) activity and mineralization ability and significantly up-regulated expression of osteogenic genes such as ALP, osteocalcin (OC), Osterix, and Runx2 compared with control BMSCs. Furthermore, fluorescence-activated cell sorting (FACS) and immunofluorescence analyses demonstrated that BFP-3 treatment up-regulated CD44 expression. Interestingly, extracellular signal-regulated kinase 1/2 (ERK1/2) and Smad1/5/8 phosphorylation was increased by BFP-3 treatment during osteogenic differentiation. Furthermore, BFP-3-induced osteogenic differentiation was significantly decreased by treatment with ERK1/2- and Smad-specific inhibitors. These results suggest that BFP-3 plays an important role in regulating osteogenic differentiation of BMSCs through increasing levels of osteogenic-inducing factors and regulating the ERK1/2 and Smad1/5/8 signaling pathways. Our finding indicates that BFP-3 may be a potential new therapeutic target for promoting bone formation.

Pseudane-VII Isolated from Pseudoalteromonas sp. M2 Ameliorates LPS-Induced Inflammatory Response In Vitro and In Vivo.

The ocean is a rich resource of flora, fauna, food, and biological products. We found a wild-type bacterial strain, Pseudoalteromonas sp. M2, from marine water and isolated various secondary metabolites. Pseudane-VII is a compound isolated from the Pseudoalteromonas sp. M2 metabolite that possesses anti-melanogenic activity. Inflammation is a response of the innate immune system to microbial infections. Macrophages have a critical role in fighting microbial infections and inflammation. Recent studies reported that various compounds derived from natural products can regulate immune responses including inflammation. However, the anti-inflammatory effects and mechanism of pseudane-VII in macrophages are still unknown. In this study, we investigated the anti-inflammatory effects of pseudane-VII. In present study, lipopolysaccharide (LPS)-induced nitric oxide (NO) production was significantly decreased by pseudane-VII treatment at 6 µM. Moreover, pseudane-VII treatment dose-dependently reduced mRNA levels of pro-inflammatory cytokines including inos, cox-2, il-1ß, tnf-α, and il-6 in LPS-stimulated macrophages. Pseudane-VII also diminished iNOS protein levels and IL-1ß secretion. In addition, Pseudane-VII elicited anti-inflammatory effects by inhibiting ERK, JNK, p38, and nuclear factor (NF)-κB-p65 phosphorylation. Consistently, pseudane-VII was also shown to inhibit the LPS-stimulated release of IL-1ß and expression of iNOS in mice. These results suggest that pseudane-VII exerted anti-inflammatory effects on LPS-stimulated macrophage activation via inhibition of ERK, JNK, p38 MAPK phosphorylation, and pro-inflammatory gene expression. These findings may provide new approaches in the effort to develop anti-inflammatory therapeutics.

The stability of water- and fat-soluble vitamin in dentifrices according to pH level and storage type.

The purpose of this study is to evaluate the vitamin stabilities in dentifrices by analyzing various vitamins according to the level and storage temperature. The stabilities of water- and fat-soluble vitamins were investigated in buffer solution at different pH values (4, 7, 8, 10 and 11) for 14 days and in dentifrices at different pH (7 and 10) for 5 months at two temperature conditions (room and refrigeration temperature) by analyzing the remaining amounts using HPLC methods. In the buffer solution, the stability of vitamins B1 , B6 and C was increased as the pH values increased. Vitamins E and K showed poor stability at pH 4, and vitamin B3 showed poor stability at pH 11. In dentifrices, the storage temperature highly influenced vitamin stability, especially vitamins C and E, but the stabilities of vitamins B1 and C according to pH values did not correspond to the buffer solution tests. Vitamin B group was relatively stable in dentifrices, but vitamin C completely disappeared after 5 months. Vitamin K showed the least initial preservation rates. Vitamins were not detected in commercial dentifrices for adults and detected amounts were less than the advertised contents in dentifrices for children.

Expression of Phospholipase D in Periodontitis and Its Role in the Inflammatory and Osteoclastic Response by Nicotine- and Lipopolysaccharide-Stimulated Human Periodontal Ligament Cells.

BACKGROUND: The aim of the present study is to investigate the expression of phospholipase D (PLD) 1 and PLD2 in periodontal patients and in human periodontal ligament cells (HPDLCs) exposed to nicotine plus lipopolysaccharide (LPS) from Porphyromonas gingivalis (Toll-like receptor 2 ligand). Furthermore, the effects of PLD isoform inhibition on the inflammatory response and osteoclast differentiation and its mechanisms were determined. METHODS: Proinflammatory mediators were examined by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. To silence the gene expression of the PLD isoforms, cells were transfected with small interfering RNA (siRNA) targeting PLD1 or PLD2. Mouse bone marrow-derived macrophages (BMMs) were used as osteoclast precursor cells for in vitro osteoclastogenesis. Western blot analysis and immunofluorescence were used to assess signaling pathways. RESULTS: Chronic smokers with periodontitis exhibited significantly higher PLD1 and PLD2 messenger RNA (mRNA) expression than non-smokers with periodontitis and healthy controls. Nicotine and LPS upregulated PLD1 and PLD2 mRNA expression in a dose-dependent manner in HPDLCs. Pharmacologic and siRNA-mediated inhibition of PLD1 and PLD2 attenuated the nicotine- and LPS-induced upregulation of inducible nitric oxide (NO) synthase and cyclooxygenase-2, production of NO, and prostaglandin E2, and mRNA expression and secretion of tumor necrosis factor-α, interleukin (IL)-1ß, and IL-8. The conditioned media from HPDLCs treated with PLD isoform inhibitors or siRNA against PLD inhibited receptor activator of nuclear factor-κB (NF-κB) ligand-mediated osteoclast differentiation, as well as protein expression of nuclear factor of activated T cells c1 and c-Fos, in BMMs. In addition, PLD isoform inhibitors and siRNA inhibited the nicotine- and LPS-induced activation of phosphoinositide 3-kinase, protein kinase C, p38, extracellular signal-regulated kinase, c-Jun N-terminal protein kinase, mitogen-activated protein kinase, and NF-κB. CONCLUSION: To the best of the authors' knowledge, this study is the first to demonstrate that PLD isoform inhibition has anti-inflammatory and antiosteoclastogenic effects and thus may be a therapeutic target for the treatment of periodontitis.

The effect of polymerization conditions on the amounts of unreacted monomer and bisphenol A in dental composite resins.

The aim of this study was to analyze the unreacted monomers of four commonly used composite resins, which were released after curing with different polymerization conditions. Four composite resins, consisting of two hybrid types and two flowable types from two manufacturers, were photopolymerized using different curing times and curing distances. After polymerization, samples were extracted for analysis at different time points up to 24 h. Released monomers were analyzed by reversed-phase liquid chromatography at UV 210 nm. Longer curing times and shorter curing distances resulted in higher polymerization rates and decreased release of TEGDMA and UDMA, but changes in curing time and distance had no significant effect on Bis-GMA. Release of BPA increased with increase in curing time or decrease in curing distance, in contrast to the results of TEGDMA and UDMA. Polymerization conditions need to be differently applied according to both monomer and resin types.

Odontogenic stimulation of human dental pulp cells with bioactive nanocomposite fiber.

The aim of the present study was to investigate the effects of a composite nanofibrous matrix made of biopolymer blend polycaprolactone-gelatin (BP) and mesoporous bioactive glass nanoparticles (BGNs) on the odontogenic differentiation of human dental pulp cells (HDPCs). BGN-BP nanomatrices, with BGN content of up to 20 wt%, were produced via electrospinning. The differentiation of the HDPCs was evaluated by using an ALP activity assay, calcified nodule formation, and mRNA expression for markers. Integrin and its underlying signal pathways were assessed via reverse transcriptase-polymerase chain reaction and Western blot analysis. Although cell growth and attachment on the BGN-BP nanomatrix was similar to that on BP, ALP activity, mineralized nodule formation, and mRNA, expressions involving ALP, osteocalcin, osteopontin, dentin sialophosphoprotein, and dentin matrix protein-1 were greater on BGN-BP. BGN-BP upregulated the key adhesion receptors (integrin components α1, α2, α5, and ß1) and activated integrin downstream pathways, such as phosphorylated-focal adhesion kinase (p-FAK), and p-paxillin. In addition, BGN-BP activated BMP receptors, BMP-2 mRNA, and p-Smad 1/5/8, and such activation was blocked by the BMP antagonist, noggin. Furthermore, BGN-BP induced phosphorylation of extracellular signal-regulated kinase, protein kinase 38, and c-Jun-N-terminal kinase mitogen-activated protein kinases and activated expression of the transcription factors Runx2 and Osterix in HDPCs. Collectively, the results indicated for the first time that a BGN-BP composite nanomatrix promoted odontogenic differentiation of HDPCs through the integrin, BMP, and mitogen-activated protein kinases signaling pathway. Moreover, the nanomatrix is considered to be promising scaffolds for the culture of HDPCs and dental tissue engineering.

Effects of bioactive cements incorporating zinc-bioglass nanoparticles on odontogenic and angiogenic potential of human dental pulp cells.

BACKGROUND: The objective of this study was to investigate the effects of bioactive calcium phosphate cements (CPC, α-tricalcium phosphate-based) incorporating zinc-bioglass (ZnBG) on the odontogenic differentiation and angiogenesis of human dental pulp cells (HDPCs). METHODS: BGs with varying concentrations of Zn (0, 2.5 and 5%) were produced via a sol-gel process. The proliferation of HDPCs on CPC/BGs was determined by MTS assay. Alizarin red staining, RT-PCR, and ALP activity were used to assess odontogenic differentiation, and western blot analysis was used to asses signaling pathways. In vitro angiogenesis was examined via mRNA expression of angiogenic genes and tubule formation. RESULTS: All cement formulations showed no cytotoxicity. The CPCs with ZnBG showed increased ALP activity, enhanced formation of mineralized nodules, and upregulated mRNA expression of DMP-1, DSPP, Runx2, and osterix in a time- and dose-dependent manner, relative to CPCs without Zn. ZnBG upregulated integrins α1, α2, ß1, and ß3 and activated integrin downstream signal pathways, such as p-FAK, p-Akt, p-paxillin, RhoA, MAPK, and NF-κB, as well as canonical and non-canonical Wnt signaling. In addition, ZnBG upregulated VEGF mRNA in HDPCs and increased the tubular structure in endothelial cells. CONCLUSIONS: Our results demonstrate that ZnBG incorporated within CPCs activates odontogenic differentiation and promotes angiogenesis in vitro through integrin, Wnt, MAPK, and NF-κB pathways. Thus, CPCs incorporating ZnBG are promising matrices in tissue engineering to stimulate endodontic regeneration.

Analysis of green tea compounds and their stability in dentifrices of different pH levels.

In this study, green tea compounds (flavonoids, alkaloids, and phenolic acids) were analyzed in green tea-containing dentifrices, and their stability at different pH levels was evaluated. The compounds were separated under 0.01% phosphoric acid-acetonitrile gradient conditions and detected by photodiode array detector at 210, 280, 300, 335 nm. Column temperature was set at 20°C based on the results of screening various temperatures. Each compound showed good linearity at optimized wavelength as well as showing good precision and accuracy in dentifrices. Using this method, the stability of compounds was investigated in pH 4, 7, 8, and 10 solutions for 96 h, and in pH 7 and pH 10 solutions for 6 months. The green tea compounds were more stable at low pH levels; purine alkaloids were more stable than flavonoids. In particular, gallocatechin (GC), epigallocatechin (EGC), epigallocatechin gallate (EGCG), gallocatechin gallate (GCG), and myricetin almost disappeared in pH 10 solutions after 96 h. In dentifrices, the compounds were gradually decreased until 6 months in both pH types, while gallic acid was increased because of production of galloyl ester of other green tea compounds. Therefore, it is beneficial to adjust to as low a pH as possible when produce green tea-containing dentifrices.

Analysis of parabens in dentifrices and the oral cavity.

This study analyzed levels of parabens in commercial dentifrices and saliva. HPLC was performed using 35% acetonitrile and measuring absorbance at 254 nm. Thirteen toothpastes and five mouthwashes were analyzed. Of these, volunteers used three toothpastes and two mouthwashes, and levels of parabens were analyzed in saliva and water used for mouth rinsing. In toothpastes, the highest concentrations of methylparaben (MP), propylparaben (PP) and n-butylparaben (nBP) were 1.86, 1.42 and 1.87 mg/g, respectively. In mouthwashes, the highest concentrations of MP and PP were 0.97 and 0.11 mg/mL, respectively. After volunteers used 500 mg toothpaste T-1, which contained 895 µg MP, the first and tenth mouth rinse samples contained means of 64.63 and 1.89 µg MP, respectively. After rinsing the mouth three or five times, 37 µg or 18 µg MP was calculated to remain in the oral cavity, respectively. After using 20 mL mouthwash S-1, which contained 19 mg MP, 1.53 mg MP was calculated to remain in the oral cavity. Immediately after using this mouthwash, the mean salivary concentration of MP was 237 µg/mL. The daily intake of parabens from dentifrices was predicted to be insignificant compared with the intake from food; however, parabens can be ingested from dentifrices.

Analyses of organic acids and inorganic anions and their relationship in human saliva before and after glucose intake.

OBJECTIVES: The goals of this study were to determine the content of organic acids and inorganic anions in human saliva by using an ion chromatography method, to compare the organic acid and inorganic anion concentrations before and after a sugar rinse, and to investigate the relationships between the levels of each compound. DESIGN: Saliva samples were obtained from 37 subjects before and up to 60min after intake of a 10% glucose solution. Concentrations of seven organic acids (lactate, acetate, propionate, formate, butyrate, pyruvate, and valerate) and four inorganic anions (fluoride, chloride, sulphate, and phosphate) were determined via anion-exchange chromatography with an anion-suppressed conductivity detector. RESULTS: The current analytical method showed good precision and accuracy. Organic acid levels increased after the sugar rinse and recovered to control levels within 20min. Acetate was the predominant organic acid detected in the saliva before the sugar rinse, and lactate was the predominant organic acid detected after the sugar rinse. The overall organic acid content generated by the sugar rinse was positively correlated with the chloride, sulphate, and phosphate concentration, but somewhat negatively correlated with the fluoride concentration. CONCLUSIONS: Organic acid levels are increased in human saliva by glucose metabolism. Furthermore, the formation of organic acids following glucose intake is influenced by the prevailing anion content.

Hesperetin alleviates the inhibitory effects of high glucose on the osteoblastic differentiation of periodontal ligament stem cells.

Hesperetin (3',5,7-trihydroxy-4-methoxyflavanone) is a metabolite of hesperidin (hesperetin-7-O-rutinoside), which belongs to the flavanone subgroup and is found mainly in citrus fruits. Hesperetin has been reported to be an effective osteoinductive compound in various in vivo and in vitro models. However, how hesperetin effects osteogenic differentiation is not fully understood. In this study, we investigated the capacity of hesperetin to stimulate the osteogenic differentiation of periodontal ligament stem cells (PDLSCs) and to relieve the anti-osteogenic effect of high glucose. Osteogenesis of PDLSCs was assessed by measurement of alkaline phosphatase (ALP) activity, and evaluation of the mRNA expression of ALP, runt-related gene 2 (Runx2), osterix (OSX), and FRA1 as osteogenic transcription factors, as well as assessment of protein expression of osteopontin (OPN) and collagen type IA (COLIA). When PDLSCs were exposed to a high concentration (30 mM) of glucose, osteogenic activity decreased compared to control cells. Hesperetin significantly increased ALP activity at doses of 1, 10, and 100 µM. Pretreatment of cells with hesperetin alleviated the high-glucose-induced suppression of the osteogenic activity of PDLSCs. Hesperetin scavenged intracellular reactive oxygen species (ROS) produced under high glucose condition. Furthermore, hesperetin increased the activity of the PI3K/Akt and ß-catenin pathways. Consistent with this, blockage of Akt or ß-catenin diminished the protective effect of hesperetin against high glucose-inhibited osteogenic differentiation. Collectively, our results suggest that hesperetin alleviates the high glucose-mediated suppression of osteogenic differentiation in PDLSCs by regulating ROS levels and the PI3K/Akt and ß-catenin signaling pathways.

A simultaneous analysis method for Caihu-Dayuan-Yin using reversed-phase high-performance liquid chromatography coupled with pulsed amperometric detection.

A simultaneous analysis method was developed for Caihu-Dayuan-Yin decoction containing Bupleuri Radix, Glycyrrhizae Radix, and Ponciri fructus by reversed-phase (RP) HPLC coupled with pulsed amperometric detection (PAD). The analytes were separated in a RP column with 0.01 % phosphoric acid-acetonitrile gradient elution. The limits of detection (S/N = 3) and of quantification (S/N = 10) ranged 0.1-3.0, and 0.3-10 ng, respectively. The intra- and interday precisions (RSDs) were ≤15.15 % and the average recoveries were 94.6-98.3 %. Our RP-HPLC-PAD method showed 1.7-100 times higher sensitivity than the RP-HPLC-UV method.

Astragaloside content in the periderm, cortex, and xylem of Astragalus membranaceus root.

Astragalosides are among the most predominant of the bioactive compounds in the root of Astragalus membranaceus and are differentially concentrated depending on the anatomical part of the root in question. The aim of this study was to analyse astragaloside contents in the periderm, cortex, and xylem of A. membranaceus root, and to compare the contents between peeled and unpeeled roots. Total astragalosides in the periderm were about 8-fold more concentrated than in the cortex, and 28-fold more concentrated than in the xylem. The dry weight percentages of total astragalosides in primary roots were 43.5% in the periderm, 47.2% in the cortex, and 9.30% in the xylem. Furthermore, unpeeled main (primary) roots were enriched in astragalosides by 1.46-fold compared with peeled main roots, whereas unpeeled lateral roots were enriched by 2.33-fold compared with peeled lateral roots. In conclusion, the periderm is the most astragaloside-rich part of the root of A. membranaceus. Therefore, it is necessary to preserve the periderm in order to supply astragaloside-rich roots for use as health food supplements.

Development of an analytical method for yam saponins using HPLC with pulsed amperometric detection at different column temperatures.

Yam saponins (dioscin, gracillin, protodioscin, and protogracillin) were analyzed with three different C18 columns at incremental column temperatures from 15 to 45°C to investigate the effect of temperature on the retention and resolution of yam saponins. At low temperature, yam saponins showed decreased retention times and improved resolutions in the C18 columns. In the Kinetex C18 column at 15°C, the four saponins achieved baseline separation (Rs > 1.5) within 30 min. Pulsed amperometric detection was used to identify saponins with high sensitivity. The limits of detection and quantification of saponins were 0.11-0.31 and 0.33-0.95 ng, respectively. The correlation coefficients ranged 0.9986-1.0000. Intra- and inter-day precisions were <4.2% of retention times and <9.5% of the calculated contents. Average recoveries ranged from 92.18 to 105.98%. Saponin contents in Dioscorea nipponica tubers and commercial yam foods were determined without sample purification or concentration. Among the ten commercial yam foods investigated, only three showed significant saponin contents.

Estimation of the costs of smoking-related oral disease: a representative South Korean study.

OBJECTIVES: The objectives of this study were to estimate the socioeconomic and psychological costs associated with smoking-related oral disease (SROD) with the aim of generating objective data that could be used in smoking cessation counselling by dental care providers and could also serve as data with which to set standards and criteria for use in dental health insurance. METHODS: Patients were sourced from the 11 dental hospitals associated with dental schools in South Korea. A total of 1,288 of 10,080 patients with SROD were selected to participate in the study for a period of 2 years from January 2009 to March 2011. Data collected were analysed using spss Version 17.0. RESULTS: Among the SRODs, the most common was periodontal disease (40.7%). Periodontal disease accounted for the highest social and economic costs. Mouth cancer accounted for the highest psychological cost. CONCLUSIONS: In order to reduce associated socioeconomic and psychological costs, dental care providers and government should provide more proactive and more efficient smoking cessation programmes.

Porphyromonas gingivalis lipopolysaccharide regulates interleukin (IL)-17 and IL-23 expression via SIRT1 modulation in human periodontal ligament cells.

Increased interleukin (IL)-17 and IL-23 levels exist in the gingival tissue of periodontitis patients, but the precise molecular mechanisms that regulate IL-17 and IL-23 production remain unknown. The aim of this study was to explore the role of SIRT1 signaling on Porphyromonas gingivalis lipopolysaccharide (LPS)-induced IL-17 and IL-23 production in human periodontal ligament cells (hPDLCs). IL-17 and IL-23 production was significantly increased in LPS-treated cells. LPS treatment also led to the upregulation of SIRT1 mRNA and protein expression. LPS-induced IL-17 and IL-23 upregulation was attenuated by pretreatment with inhibitors of phosphoinositide 3-kinase (PI3K), p38, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), mitogen-activated protein kinase (MAPK), and NF-κB, as well as neutralizing antibodies against Toll-like receptors (TLRs) 2 and 4. Sirtinol treatment (a known SIRT1 inhibitor) or SIRT1 knockdown by small interfering RNA blocked LPS-stimulated IL-17 and IL-23 expression. Further investigation showed that LPS decreased osteoblast markers (i.e., ALP, OPN, and BSP) and concomitantly increased osteoclast markers (i.e., RANKL and M-CSF). This response was attenuated by inhibitors of the PI3K, p38, ERK, JNK, NF-κB, and SIRT1 pathways. These findings, for the first time, suggest that human periodontopathogen P. gingivalis LPS is implicated in periodontal disease bone destruction and may mediate IL-17 and IL-23 release from hPDLCs. This process is dependent, at least in part, on SIRT1-Akt/PI3K-MAPK-NF-κB signaling.