Antibacterial and antioxidant effect of ethanol extracts of Terminalia chebula on Streptococcus mutans.

OBJECTIVE: Dental caries is a high prevalent chronic bacterial infectious disease caused by plaque, a bacterial colony deposited on tooth surfaces and gum tissues. Streptococcus mutans is a primary cariogenic bacterium commonly found in the human oral cavity. Oral hygiene products containing antibacterial ingredients can be helpful in caries management. In this study, we investigated the anticaries mechanism of the ethanol extract of Terminalia chebula (EETC) on S. mutans and suggest its possible application as a functional ingredients for oral hygiene products. MATERIALS AND METHODS: The EETC was prepared from the Terminalia chebula fruit. Disk diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and colony forming unit (CFU) were analyzed to observe the antibacterial activity of EETC. The glucan formation was measured using the filtrate of bacterial culture medium and sucrose. Gene expression was analyzed using RT-PCR. Cytotoxicity was analyzed using the MTT assay. The radical-scavenging activities of DPPH and ABTS were also tested to verify the antioxidant activity of EETC. RESULTS: The antibacterial activity of the EETC was explored through a disc diffusion analysis and CFU measurement. EETC treatment decreased insoluble glucan formation and gene expression of glycosyltransferase B (gtf B), glycosyltransferase C (gtf C), glycosyltransferase D (gtf D), and fructosyltransferase (ftf). The MIC and MBC of EETC on S. mutans were not cytotoxic to gingival fibroblasts. In addition, we observed DPPH and ABTS-radical scavenging activities of EETC. CONCLUSIONS: These results indicate that the antibacterial and antioxidant effects of EETC may contribute to oral hygiene products for dental caries management.

Anti-Periodontitis Effect of Ethanol Extracts of Alpinia Katsumadai Seeds.

Oral microbes are intimately associated with many oral and systemic diseases. Ongoing research is seeking to elucidate drugs that prevent and treat microbial diseases. Various functions of Alpinia Katsumadai seed extracts have been reported such as their anti-viral, anti-oxidant, anti-inflammatory, anti-puritic, anti-emetic, and cytoprotective effects. Here, we investigated the anti-periodontitis effect of an ethanol extract of Alpinia Katsumadai seeds (EEAKSs) on dental plaque bacteria (DPB)-induced inflammation and bone resorption. DPB and Porphyromonas gingivalis (P. gingivalis) were cultured and lipopolysaccharide (LPS) was extracted. Prostaglandin E2 (PGE2) and cyclooxygenase 2 (COX-2) levels were estimated using ELISA. Cytotoxicity was also verified. Proteases were screened using a protease antibody array method. Osteoclastic bone resorption was also investigated. EEAKSs suppressed P. gingivalis growth on agar plates. LPS prepared from dental plaque bacteria (DPB-LPS) and P. gingivalis (PG-LPS) significantly increased PGE2 and COX2 levels in immortalized gingival fibroblasts (IGFs), immortalized human oral keratinocytes (IHOKs), and RAW264.7 macrophage cells. However, DPB-LPS and PG-LPS-induced PGE2 and COX-2 increases were effectively abolished by EEAKS treatment at non-cytotoxic concentrations. In the protease antibody array, matrix metalloproteinase (MMP)-2, MMP-3, MMP-7, kallikrein 10, cathepsin D, and cathepsin V levels were increased by PG-LPS stimulation. However, increases in protease levels except for cathepsin D were suppressed by EEAKS treatment. In addition, RANKL-induced osteoclast differentiation was significantly inhibited by EEAKS treatment, leading to reductions in resorption pit formation. These results suggest that EEAKSs exerted a beneficial oral health effect to help prevent DPB-mediated periodontal disease.

Anti-invasive and Anti-tumor Effects of Dryopteris crassirhizoma Extract by Disturbing Actin Polymerization.

AIM: To evaluate the anti-invasive effect of ethanol extracts of rhizome of Dryopteris crassirhizoma (EEDC) in matrix invasion and formation of functional invadopodia and to determine the anti-tumor effect of EEDC in a mouse model of mandibular invasion by gingival squamous cell carcinoma (SCC). METHODS: The rhizome of D crassirhizoma was extracted in ethanol. The anti-invasive effect of EEDC was analyzed with a Matrigel-coated transwell invasion and 3D culture system. Crucial factors related to the control of cancer cell invasion by EEDC were determined using a human protease array. Molecular evidence supporting the anti-invasive effect of EEDC in oral SCC (OSCC) cells used an invadopodia-mediated extracellular matrix (ECM) degradation; an in vivo athymic mouse model was also provided. RESULTS: EEDC treatment (10 µg/mL) suppressed transwell migration and invasion of HSC-3 OSCC cells without cytotoxicity. Decreased levels of matrix metalloprotease (MMP)-7, kalikrein 10, cathepsin V, MMP-2, and cathepsin D were also found in EEDC-treated HSC-3 cells based on human protease array. The anti-invasive effects of EEDC involved the suppression of invadopodia-mediated ECM degradation via inhibition of globular-actin elongation. The anti-invasive effect resulting from disturbance of functional invadopodia formation by EEDC was observed even at a low concentration of 5 µg/mL. The phosphorylation of cortactin involved in functional invadopodia formation was decreased at EEDC concentrations that inhibited invadopodia formation. The anti-tumor effect of EEDC was also observed in a mouse xenograft model. Administration of EEDC resulted in inhibition of tumor growth and progression. CONCLUSIONS: EEDC represents a potential anti-invasive and anti-tumor agent in cancer control.

Use of ethanol extracts of Terminalia chebula to prevent periodontal disease induced by dental plaque bacteria.

BACKGROUND: The fruit of the Terminalia chebula tree has been widely used for the treatment of various disorders. Its anti-diabetic, anti-mutagenic, anti-oxidant, anti-bacterial, anti-fungal, and anti-viral effects have been studied. Dental plaque bacteria (DPB) are intimately associated with gingivitis and periodontitis. In the quest for materials that will prove useful in the treatment and prevention of periodontal disease, we investigated the preventive effects of an ethanol extract of Terminalia chebula (EETC) on DPB-induced inflammation and bone resorption. METHODS: The anti-bacterial effect of EETC was analyzed using the disc diffusion method. The anti-inflammatory effect of EETC was determined by molecular biological analysis of the DPB-mediated culture cells. Prevention of osteoclastic bone resorption by EETC was explored using osteoclast formation and pit formation assays. RESULTS: EETC suppressed the growth of oral bacteria and reduced the induction of inflammatory cytokines and proteases, abolishing the expression of PGE2 and COX-2 and inhibiting matrix damage. By stimulating the DPB-derived lipopolysaccharides, EETC inhibited both osteoclast formation in osteoclast precursors and RANKL expression in osteoblasts, thereby contributing to the prevention of bone resorption. CONCLUSIONS: EETC may be a beneficial supplement to help prevent DPB-mediated periodontal disease.

The characterization of caffeine and nine individual catechins in the leaves of green tea (Camellia sinensis L.) by near-infrared reflectance spectroscopy.

Near-infrared reflectance spectroscopy (NIRS) was used to determine the contents of caffeine and nine individual catechins in tea leaves. A total of 665 samples were scanned by NIRS, and also by high performance liquid chromatography coupled to a diode array detector to determine the contents of caffeine and nine individual catechins. The calibration models for caffeine, EGC, C, EGCG, EC, ECG, and total catechins had high r(2) (more than 0.90) and RSP (the ratio of standard deviation of reference data to SEP(C) in the external validation set) values (more than 4.1), indicating a good correlation between reference values and NIRS predicted values. In contrast, the calibration models of GC and EGCG-3Me had low r(2) and RSP values (below 0.8 and 2.0). Therefore, these results suggest that NIRS could be applied for the rapid determination of the contents of caffeine, EGC, C, EGCG, EC, ECG, and total catechins in tea leaves for breeding programs that develop high-quality tea plants.

Buddlejasaponin IV induces cell cycle arrest at G2/M phase and apoptosis in immortalized human oral keratinocytes.

Buddlejasaponin IV (BS-IV), a major component of Pleurospermum kamtschaticum, exerts antiinflammatory and cytotoxic effects against cancer cells. The study investigated whether BS-IV could prevent oral carcinogenesis by inhibiting the growth of immortalized human oral keratinocytes (IHOKs). BS-IV reduced cell viability and induced cell cycle arrest at G2/M phase and apoptotic morphological changes in IHOKs. BS-IV inhibited the levels of cyclin B1, Cdc2 and Cdc25C, but enhanced Chk2 phosphorylation. The increased levels of pRb and p21 protein and the activation of p53 were also noted in BS-IV-treated IHOKs. In addition, BS-IV induced cytochrome c release from mitochondria by reducing antiapoptotic Bcl-2 levels and increasing pro-apoptotic Bax levels. BS-IV treatment resulted in the activation of caspase-9 and caspase-3. PARP cleavage was also clearly observed in the BS-IV-treated IHOKs. Furthermore, the expression of the Fas death receptor and Fas ligand was induced and procaspase-8 level was suppressed by BS-IV treatment. Taken together, BS-IV treatment inhibited the growth of IHOK cells via the induction of p53-dependent cell cycle arrest at the G2/M phase and apoptosis via both mitochondrial-dependent and death receptor-mediated pathways. Thus, BS-IV can be considered an excellent candidate for a chemopreventive agent to block the progression of HPV-induced oral carcinogenesis.

Hwangryun-Hae-Dok-tang (Huanglian-Jie-Du-Tang) extract and its constituents reduce ischemia-reperfusion brain injury and neutrophil infiltration in rats.

The preventive effect of Hwangryun-Hae-Dok-tang (HHDT, Huanglian-Jie-Du-Tang), a Chinese herbal medicine, and its ingredients on ischemia/reperfusion-induced brain injury was evaluated in the rat brain. HHDT consists of four herbs, namely, Coptidis rhizoma, Scutellariae radix, Phellodendri cortex, and Gardeniae fructus. Ischemia was induced by intraluminal occlusion of the right middle cerebral artery for 120 min and reperfusion was continued for 22 h. HHDT (200 mg/kg), Coptidis rhizoma (100 mg/kg), Scutellariae radix (100 mg/kg), Phellodendri cortex (100 mg/kg), and Gardeniae fructus (100 mg/kg) were orally administered, promptly prior to reperfusion and 2 h after reperfusion. Baicalein, a component of Scutellariae radix, was also examined at a dosage of 50 mg/kg given 2 h apart, promptly prior to and 2 h after reperfusion. Total infarction volume in the ipsilateral hemisphere of ischemia/reperfusion rats was significantly lowered by treatment with HHDT, Scutellariae radix, and balicalein. However, the other ingredient of HHDT did not show any ameliorating effects on total infarction volume. The inhibiting effect of Scutellariae radix on total infarction volume was much higher than that of the others. In addition, HHDT, Scutellariae radix, and baicalein significantly inhibited myeloperoxidase (MPO) activity, an index of neutrophil infiltration in ischemic brain tissue at about the same rate (30%). There was marked mismatch between total infarction volume and MPO activity in the Scutellariae radix-treated rats but not in the HHDT- and baicalein-treated groups. Our findings suggest that Scutellariae radix as an ingredient of HHDT plays a crucial protective role in ischemia-induced brain injury. In addition, it is apparent that the effect of Scutellariae radix is the result, in part, of baicalein, a compound contained in Scutellariae radix.