ANTIBACTERIAL EFFECT OF CRATAEGUS PINNATIFIDA EXTRACT AGAINST ENTROCOCCUS FAECALIS A ROOT CANAL DISEASE-CAUSING BACTERIA.

Studies have substantiated the anti-inflammatory and anti-thrombotic effects of (C. pinnatifida); however, research on its antibacterial activity using organic solvent remains limited. Therefore, in this study, we aimed to validate the antibacterial activity of C. pinnatifida as a natural extract against Enterococcus faecalis (E. faecalis), a multidrug-resistant bacterium. E. faecalis was treated with different concentrations of C. pinnatifida to determine the optimal concentration for the most effective antibacterial effect. Fifteen different concentrations were applied for 6 and 24 h. The experimental method centered on confirming antibacterial activity using colony-forming units. The experimental results demonstrated a proportional increase in antibacterial activity with elevated C. pinnatifida concentration. Notably, 99.99% and 100% antibacterial activity were observed at 10 mg/mL and 40 mg/mL concentrations, respectively. Our results suggest that C. pinnatifida holds potential as an antibacterial agent against the multidrug-resistant E. faecalis.

GROWTH INHIBITORY EFFECT OF HOUTTUYNIA CORDATA EXTRACT ON STREPTOCOCCUS MUTANS.

Houttuynia cordata is an herbal plant distributed throughout Asia. H. cordata has many bioactive properties, including antibacterial properties. The antibacterial effects of H. cordata on S. mutans remain unknown. Therefore, we treated S. mutans with 1, 3, 5, 10, 20, 30, or 40 mg/mL H. cordata extract at 37°C for 24 h. The antibacterial effect of H. cordata against S. mutans was confirmed using colony forming unit assay and disk diffusion assays. The results of the cell concentration assay demonstrated that H. cordata inhibited the growth of S. mutans in a dose-dependent manner. Prominent growth inhibition was observed after treatment with 10 mg/mL H. cordata extract, and these findings were statistically significant. In addition, no colonies of S. mutans were detected after treatment with 40 mg/mL H. cordata. Disk diffusion assays revealed that 20 mg/mL of H. cordata created a zone of growth inhibition of 11 mm. Therefore, our findings suggest the possibility of using H. cordata in the treatment and prevention of dental caries.

Cudraxanthone D Regulates Epithelial-Mesenchymal Transition by Autophagy Inhibition in Oral Squamous Cell Carcinoma Cell Lines.

Cudraxanthone D (CD), derived from the root bark of Cudrania tricuspidata, is a natural xanthone compound. However, the biological activity of CD in terms of human metabolism has been barely reported to date. Autophagy is known as a self-degradation process related to cancer cell viability and metastasis. Herein, we investigated the effects of CD on human oral squamous cell carcinoma (OSCC) metastatic related cell phenotype. We confirmed that CD effectively decreased proliferation and viability in a time- and dose-dependent manner in human OSCC cells. In addition, OSCC cell migration, invasion, and EMT were inhibited by CD. To further determine the underlying mechanism of CD's inhibition of cell metastatic potential, we established the relationship between EMT and autophagy in OSCC cells. Thus, our findings indicated that CD inhibited the potential metastatic abilities of OSCC cells by attenuating autophagy.

Crosstalk between Fisetin-induced Apoptosis and Autophagy in Human Oral Squamous Cell Carcinoma.

Fisetin (3,3-,4-,7-tetrahydroxyflavone), a naturally occurring flavonoid, has antioxidant, anti-inflammatory, and anticancer effects. Oral squamous cell carcinoma (OSCC) has a 5-year survival rate lower than that of most other carcinomas, and can create functional and aesthetic problems for the patient. New therapies for OSCC are necessary, and treatment using plant-derived natural substances has recently become a trend. It has been suggested that autophagy may play an important role in cancer therapy. Several studies demonstrated that autophagy inhibition enhances apoptotic cell death. Therefore, autophagy inhibition might be a promising therapeutic method against OSCC. Our results showed that fisetin induced apoptotic cell death in human tongue squamous cell line Ca9-22 could be enhanced by inhibition of autophagy. Thus, autophagy process in fisetin treated OSCC might presumed to play a role of pro-survival. The combination of fisetin and an effective autophagy inhibitor could be a potentially adjuvant and useful treatment for oral cancer.

Cordycepin Accelerates Osteoblast Mineralization and Attenuates Osteoclast Differentiation In Vitro.

Bone homeostasis destruction is triggered by the uncontrolled activity of osteoblasts and osteoclasts. Targeting both the regulation of bone formation and resorption is a promising strategy for treating bone disorders. Cordycepin is a major component of Chinese caterpillar fungus Cordyceps militaris. It exerts a variety of biological actions in various cells and animal models. However, its function on bone metabolism remains unclear. In the present study, we discovered a dual-action function of cordycepin in murine MC3T3-E1 and RAW264.7 cells. MC3T3-E1 cells were cultured in an osteogenic medium in the presence of 1 µM cordycepin for up two weeks. Cordycepin was used for effects of osteoblast and osteoclast differentiation. Cell viability was measured using the MTT assay. Osteoblast differentiation was confirmed by alizarin red staining, ALP activity, western blot, and real-time PCR. Osteoclast differentiation and autophagic activity were confirmed via TRAP staining, pit formation assay, confocal microscopy, western blot, and real-time PCR. Cordycepin promoted osteoblast differentiation, matrix mineralization, and induction of osteoblast markers via BMP2/Runx2/Osterix pathway. On the other hand, RAW264.7 cells were differentiated into osteoclast by RANKL treatment for 72 h. 1 µM cordycepin significantly inhibited RANKL-induced osteoclast formation and resorption activity through disturbing the actin ring-formatted sealing zone and activating cathepsin K and MMP9. These findings indicate that cordycepin might be an innovative dual-action therapeutic agent for bone disease caused by an imbalance of osteoblasts and osteoclasts.

Induction of Apoptosis and Inhibition of Epithelial Mesenchymal Transition by α-Mangostin in MG-63 Cell Lines.

Osteosarcoma is the most common bone primary malignant tumor and nearly 30% of patients still die from osteosarcoma due to metastasis or recurrence. Thus, it is necessary to develop effective new chemotherapeutic agents for osteosarcoma treatment. α-Mangostin is a xanthone derivative shown to have antioxidant and anticarcinogen properties. However, the molecular mechanisms underlying the antimetastatic effects of osteosarcoma remain unclear. In metastasis progression, epithelial mesenchymal transition (EMT) is a process that plays important roles in development, cell polarity, and increased invasion and migration. This study focused on the induction of apoptosis and inhibition of EMT process by α-mangostin in human osteosarcoma cell line MG63. α-Mangostin treatments on MG63 cells not only showed the several lines of evidence of apoptotic cell death but also inhibited cell migration, invasion, and EMT-inducing transcription factor. In conclusion, we demonstrate that the α-mangostin induces apoptosis via mitochondrial pathway and suppresses metastasis of osteosarcoma cells by inhibiting EMT.

Delphinidin induces apoptosis and inhibits epithelial-to-mesenchymal transition via the ERK/p38 MAPK-signaling pathway in human osteosarcoma cell lines.

Delphinidin is major anthocyanidin that is extracted from many pigmented fruits and vegetables. This substance has anti-oxidant, anti-inflammatory, anti-angiogenic, and anti-cancer properties. In addition, delphinidin strongly suppresses the migration and invasion of various cancer cells during tumorigenesis. Although delphinidin has anti-cancer effects, little is known about its functional roles in osteosarcoma (OS). For these reasons, we have demonstrated the effects of delphinidin on OS cell lines. The effects of delphinidin on cell viability and growth of OS cells were assessed using the MTT assay and colony formation assays. Hoechst staining indicated that the delphinidin-treated OS cells were undergoing apoptosis. Flow cytometry, confocal microscopy, and a western blot analysis also indicated evidence of apoptosis. Inhibition of cell migration and invasion was found to be associated with epithelial-to-mesenchymal transition (EMT), observed by using a wound healing assay, an invasion assay, and a western blot analysis. Furthermore, delphinidin treatment resulted in a profound reduction of phosphorylated forms of ERK and p38. These findings demonstrate that delphinidin treatment suppressed EMT through the mitogen-activated protein kinase (MAPK) signaling pathway in OS cell lines. Taken together, our results suggest that delphinidin strongly inhibits cell proliferation and induces apoptosis. Delphinidin treatment also suppresses cell migration and prevents EMT via the MAPK-signaling pathway in OS cell lines. For these reasons, delphinidin has anti-cancer effects and can suppress metastasis in OS cell lines, and it might be worth using as an OS therapeutic agent.

Cytoprotective effect of flavonoid-induced autophagy on bisphosphonate mediated cell death in osteoblast.

With rapid economic growth and further developments in medical science, the entry into the aging population is currently increasing, as is the number of patients with metabolic diseases, such as hypertension, hyperlipidemia, heart disease, and diabetes. The current treatments for metabolic bone diseases, which are also on the rise, cause negative side effects. Bisphosphonates, which are used to treat osteoporosis, inhibit the bone resorption ability of osteoclasts and during prolonged administration, cause bisphosphonate-related osteonecrosis of the jaw (BRONJ). Numerous studies have shown the potential role of natural plant products as flavonoids in the protection against osteoporosis and in the influence of bone remodeling. Autophagy occurs after the degradation of cytoplasmic components within the lysosome and serves as an essential cytoprotective response to pathologic stress caused by certain diseases. In the present study, we hypothesized that the cytoprotective effects of flavonoids might be related to those associated with autophagy, an essential cytoprotective response to the pathologic stress caused by certain diseases, in osteoblasts. We demonstrated the cytoprotective effect of flavonoid-induced autophagy against the toxicity of zoledronate and the induction of autophagy by flavonoids to support osteogenic transcription factors, leading to osteoblast differentiation and bone formation. Further studies are necessary to clarify the connections between autophagy and osteogenesis. It would be helpful to shed light on methodological challenges through molecular biological studies and new animal models. The findings of the current study may help to delineate the potential role of flavonoids in the treatment of metabolic bone disease.

Propofol protects human keratinocytes from oxidative stress via autophagy expression.

BACKGROUND: The skin consists of tightly connected keratinocytes, and prevents extensive water loss while simultaneously protecting against the entry of microbial pathogens. Excessive cellular levels of reactive oxygen species can induce cell apoptosis and also damage skin integrity. Propofol (2,6-diisopropylphenol) has antioxidant properties. In this study, we investigated how propofol influences intracellular autophagy and apoptotic cell death induced by oxidative stress in human keratinocytes. METHOD: The following groups were used for experimentation: control, cells were incubated under normoxia (5% CO2, 21% O2, and 74% N2) without propofol; hydrogen peroxide (H2O2), cells were exposed to H2O2 (300 µM) for 2 h; propofol preconditioning (PPC)/H2O2, cells pretreated with propofol (100 µM) for 2 h were exposed to H2O2; and 3-methyladenine (3-MA)/PPC/H2O2, cells pretreated with 3-MA (1 mM) for 1 h and propofol were exposed to H2O2. Cell viability, apoptosis, and migration capability were evaluated. Relation to autophagy was detected by western blot analysis. RESULTS: Cell viability decreased significantly in the H2O2 group compared to that in the control group and was improved by propofol preconditioning. Propofol preconditioning effectively decreased H2O2-induced cell apoptosis and increased cell migration. However, pretreatment with 3-MA inhibited the protective effect of propofol on cell apoptosis. Autophagy was activated in the PPC/H2O2 group compared to that in the H2O2 group as demonstrated by western blot analysis and autophagosome staining. CONCLUSION: The results suggest that propofol preconditioning induces an endogenous cellular protective effect in human keratinocytes against oxidative stress through the activation of signaling pathways related to autophagy.

Propofol protects against oxidative-stress-induced COS-7 cell apoptosis by inducing autophagy.

BACKGROUND: In oxidative stress, reactive oxygen species (ROS) production contributes to cellular dysfunction and initiates the apoptotic cascade. Autophagy is considered the mechanism that decreases ROS concentration and oxidative damage. Propofol shows antioxidant properties, but the mechanisms underlying the effect of propofol preconditioning (PPC) on oxidative injury remain unclear. Therefore, we investigated whether PPC protects against cell damage from hydrogen peroxide (H2O2)-induced oxidative stress and influences cellular autophagy. METHOD: COS-7 cells were randomly divided into the following groups: control, cells were incubated in normoxia (5% CO2, 21% O2, and 74% N2) for 24 h without propofol; H2O2, cells were exposed to H2O2 (400 µM) for 2 h; PPC + H2O2, cells pretreated with propofol were exposed to H2O2; and 3-methyladenine (3-MA) + PPC + H2O2, cells pretreated with 3-MA (1 mM) for 1 h and propofol were exposed to H2O2. Cell viability was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide thiazolyl blue (MTT) reduction. Apoptosis was determined using Hoechst 33342 staining and fluorescence microscopy. The relationship between PPC and autophagy was detected using western blot analysis. RESULTS: Cell viability decreased more significantly in the H2O2 group than in the control group, but it was improved by PPC (100 µM). Pretreatment with propofol effectively decreased H2O2-induced COS-7 cell apoptosis. However, pretreatment with 3-MA inhibited the protective effect of propofol during apoptosis. Western blot analysis showed that the level of autophagy-related proteins was higher in the PPC + H2O2 group than that in the H2O2 group. CONCLUSION: PPC has a protective effect on H2O2-induced COS-7 cell apoptosis, which is mediated by autophagy activation.

XIAP inhibitor embelin induces autophagic and apoptotic cell death in human oral squamous cell carcinoma cells.

Embelin is an active ingredient of traditional herbal remedies for cancer and other diseases. Recently, it has been suggested that autophagy may play an important role in cancer therapy. However, little data are available regarding the role of autophagy in oral cancers. Therefore, we conducted this study to examine whether Embelin modulates autophagy in Ca9-22. Our results showed that Embelin had anticancer activity against the Ca9-22 human tongue squamous cell, and we observed that autophagic vacuoles were formed by MDC and AO. We also analyzed Embelin-treated Ca9-22 cells for the presence of biochemical markers and found that it directly affected the conversion of LC3-II, the degradation of p62/SQSTM1, full-length cleavage formation of ATG5-ATG12 complex and Beline-1, and caspase activation. Rescue experiments using an autophagy inhibitor showed Embelin-induced cell death in Ca9-22, confirming that autophagy acts as a pro-death signal. Furthermore, Embelin exhibited anticancer activity against Ca9-22 via both autophagy and apoptosis. These findings suggest that Embelin may potentially contribute to oral cancer treatment and provide useful information for the development of a new therapeutic agent.

Remifentanil reduced the effects of hydrogen peroxide-induced oxidative stress in human keratinocytes via autophagy.

PURPOSE: Excess reactive oxygen species are detrimental to wound repair. Remifentanil decreases reactive oxygen species generation and inflammatory response; however, its effects on oxidative cell injury are not completely understood. Therefore, we investigated the effects of remifentanil on human keratinocytes under hydrogen peroxide-induced oxidative stress and the correlation of these effects with autophagy. MATERIALS AND METHODS: Human keratinocytes (HaCaT cell line) were randomly assigned to four groups: control, hydrogen peroxide, remifentanil pretreatment + hydrogen peroxide, and 3-methyladenine + remifentanil pretreatment + hydrogen peroxide. The MTT assay was performed to analyze cell viability. Apoptotic cell death was measured by Hoechst staining. A scratch assay was used to measure cell migration. The role of autophagy was ascertained by autophagosome staining and western blot analysis of autophagy-related proteins. RESULTS: Compared with the control group, the hydrogen peroxide group showed decreased cell viability, which was improved by remifentanil pretreatment. Hydrogen peroxide-induced apoptotic cell death and delayed cell migration were also improved by remifentanil pretreatment. Western blot analysis showed that the expression of autophagy-related proteins significantly increased in the remifentanil pretreatment + hydrogen peroxide group compared with that in the hydrogen peroxide group. CONCLUSIONS: This study demonstrated that remifentanil pretreatment ameliorates hydrogen peroxide-induced oxidative injury in human keratinocytes. In addition, our results show that the antioxidative effect of remifentanil against hydrogen peroxide-induced oxidative injury was mediated by autophagy.

α-Mangostin Induces Apoptosis and Cell Cycle Arrest in Oral Squamous Cell Carcinoma Cell.

Mangosteen has long been used as a traditional medicine and is known to have antibacterial, antioxidant, and anticancer effects. Although the effects of α-mangostin, a natural compound extracted from the pericarp of mangosteen, have been investigated in many studies, there is limited data on the effects of the compound in human oral squamous cell carcinoma (OSCC). In this study, α-mangostin was assessed as a potential anticancer agent against human OSCC cells. α-Mangostin inhibited cell proliferation and induced cell death in OSCC cells in a dose- and time-dependent manner with little to no effect on normal human PDLF cells. α-Mangostin treatment clearly showed apoptotic evidences such as nuclear fragmentation and accumulation of annexin V and PI-positive cells on OSCC cells. α-Mangostin treatment also caused the collapse of mitochondrial membrane potential and the translocation of cytochrome c from the mitochondria into the cytosol. The expressions of the mitochondria-related proteins were activated by α-mangostin. Treatment with α-mangostin also induced G1 phase arrest and downregulated cell cycle-related proteins (CDK/cyclin). Hence, α-mangostin specifically induces cell death and inhibits proliferation in OSCC cells via the intrinsic apoptosis pathway and cell cycle arrest at the G1 phase, suggesting that α-mangostin may be an effective agent for the treatment of OSCC.