OBJECTIVE: To investigate the mechanism by which arecoline regulates the level of miR-155-5p in macrophage-secreted exosomes to induce the transformation of human oral mucosal fibroblasts (HOMFs) into fibroblast phenotype. METHODS: Exosomes were harvested from human monocytic cell line THP-1 with or without arecoline treatment. The effects of arecoline-treated THP-1 cell culture supernatant (CS), THP-1-derived exosomes (EXO), exosome-depleted THP-1 cell supernatant (NES), miR-155-5p overexpression, and miR-155-5p inhibitor on migration ability of arecoline-treated HOMF cells were examined using Transwell migration assay. The polarization of THP-1 cells was detected using flow cytometry. DCFH-DA was used to detect the level of oxidative stress in the cells with different treatments. The mRNA and protein expressions of α- SMA, type I collagen and SOCS1 in the cells were detected with qRT-PCR and Western blotting. RESULTS: Flow cytometry showed that arecoline-treated THP-1 cells exhibited obvious polarization from M₀ to M₁. Both the supernatant and exosomes from arecoline-treated THP-1 cells significantly enhanced the migration ability of HOMF cells, increased intracellular oxidative stress, up-regulated the expressions of miR-155- 5p and the mRNA and protein levels of α-SMA and type I collagen, and lowered the mRNA and protein expressions of SOCS1. In HOMF cells treated with exosomes from arecoline- treated THP-1 cells, overexpression of miR-155-5p significantly enhanced cell migration ability and increased cellular expressions of α-SMA and type I collagen, and miR-155-5p inhibitor caused the opposite changes. CONCLUSION Arecoline can up-regulate miR-155-5p expression in THP-1 cells and inhibit the expression of SOCS1 protein in HOMF cells via the exosome pathway, thus promoting the fibrotic phenotype transformation of HOMF cells.
Humans ; Exosomes ; Arecoline/pharmacology* ; Collagen Type I ; Fibroblasts ; Macrophages ; MicroRNAs

Streptococcus mutans (S. mutans) is a facultative anaerobic bacterium mainly found in the oral cavity and is known to contribute to tooth decay and gingivitis. Recent studies on intestinal microbiota have revealed that microorganisms forming a biofilm play important roles in maintaining tissue homeostasis through their own metabolism. However, the physiological roles of oral microorganisms such as S. mutans are still unclear. In our current study, we identified that constituents released from S. mutans (CR) reduce arecoline-mediated cytotoxicity without producing toxic effects themselves. Arecoline, as a major alkaloid of areca nut, is known to mediate cytotoxicity on oral epithelial cells and induces a sustained intracellular Ca2+ ([Ca2+]i) increase that is cytotoxic. The exposure of human gingival fibroblast (HGF) cells to CR not only inhibited the sustained [Ca2+]i increase but also the initial [Ca2+]i elevation. In contrast, CR had no effects on the gene regulation mediated by arecoline. These results demonstrate that S. mutans has physiological role in reducing cytotoxicity in HGF cells and may be considered a novel pharmaceutical candidate.
Areca ; Arecoline ; Biofilms ; Epithelial Cells ; Fibroblasts ; Gingivitis ; Homeostasis ; Humans ; Metabolism ; Microbiota ; Mouth ; Nuts ; Streptococcus mutans* ; Tooth

OBJECTIVETo develop a HPLC method for the determination of synephrine and arecoline contents in Xiao'er Xiaoji Zhike oral liquid.

METHODThe analysis was performed on a Symmetry C18 column (4.6 mm x 250 mm, 5 microm) eluted with acetonitrile-methanol-0.1% acetic acid solution (containing potassium dihydrogen phosphate 0.6 g and SDS 1.0 g per 1 000 mL) (15: 30: 55) as mobile phase. The detection wavelength was set at 215 nm.

RESULTThe synephrine and arecoline concentrations had good linear relationship between 0.281 5-2.815 and 0.040 16-0.401 6 microg (r > 0.999 7), and the average recoveries of the two compounds were 97.1% (RSD 1.4%) and 100% (RSD 1.3%), respectively.

CONCLUSIONThe method is simple, accurate and sensitive.

Arecoline ; analysis ; Chromatography, High Pressure Liquid ; methods ; Drugs, Chinese Herbal ; analysis ; Synephrine ; analysis

OBJECTIVETo prove that synthetic Are combination with snail-killing drug Nic can increase the effects of snail-killing remarkably.

METHODSIn indoor immersing experimentation, the experiments were divided into 4 groups, 30 snails in each group, to observe the rate of opening operculum, the rate of climbing adhesion and the rate of death at 3, 6 and 24 hours respectively. In field experimentation, we intermixed 0.1 mg/L Are with 0.2 mg/L Nic as sample as contrasted with 2 mg/L Nic and non-drug group. Immersing method (we chose three slots each size were 10 m x 2 m x 1 m.) and insufflation method (we chose three patch of bottomlands each area were 10 m x 5 m.) were used to kill snails separately and the death rate of fish, at the same time was observed.

RESULTSIn the room, as we added 0.1 mg/L Are to the solution of 0.1 mg/L and 0.2 mg/L Nic separately, the opening operculum rate for 6 hours was increased from 20% and 12% to 100% and 95%, the climbing adhesion rate for 6 hours decreased from 17% and 53% to 3% and 5%, the death rate for 24 hours increased from 25% and 40% to 90% and 100%. In the field, the snails death rate in sample group and in contrastive group applied with immersing method and insufflation method for 72 hours were 95.9%, 93.3% and 100%, 95.8%; only one small fish (2 cm long) died in sample group, and all fishes died in Nic group, and all fish were alive in non-drug group.

CONCLUSIONIt proved that synthetic Are combination with snail-killing drug Nic might decrease Nic dosage and toxicity and increase the effects of snail-killing.

Animals ; Arecoline ; pharmacology ; Drug Synergism ; Molluscacides ; pharmacology ; Niclosamide ; pharmacology ; Snails ; drug effects

OBJECTIVE: The aim of this study was to induce oral submucous fibrosis (OSF) in Sprague-Dawley(SD) rat models by arecoline and mechanical stimulation. METHODS: Two factors factorial design was used to divide 48 rats into 8 groups (n=6). Different concentrations of arecoline (0, 0.5, 2, and 8 mg·mL⁻¹) and mechanical stimulation (with or without brush) were treated. After 16 weeks of treatment, the mouth opening was measured, the pathological changes of the buccal mucosa were observed, and the expressions of type Ⅲ collagen, transforming growth factor β1 (TGF-β1), and interferon-γ (IFN-γ) were detected. RESULTS: In rats with moderate and high concentrations of arecoline, typical OSF pathological features were observed in the buccal mucosa, the mouth openings were significantly reduced, and the expression levels of type Ⅲ colla-gen and TGF-β1 were significantly increased (P<0.05). Although mechanical stimulation can increase the three indexes of mucosa (P<0.05), no pathological change and difference in the mouth opening was observed (P>0.05). CONCLUSIONS Moderate and high concentrations of arecoline can induce OSF in SD rats, but mechanical stimulation cannot induce OSF.
Animals ; Arecoline ; pharmacology ; Fibroblasts ; Mouth Mucosa ; Oral Submucous Fibrosis ; Rats ; Rats, Sprague-Dawley

In this study, low-field nuclear magnetic resonance(LF-NMR) and magnetic resonance imaging(MRI) were employed to analyze the water distribution, status, and migration in the moistening process of Arecae Semen. Peleg model was adopted to study the water absorption kinetics of Arecae Semen moistened at different water temperatures(10, 30, and 50 ℃). The Arecae Semen samples soaked at different water temperatures all contained four water states: binding water T_(21), non-flowing water T_(22), free water T_(23), and unbound water T_(24). Non-flowing water had the largest increase in peak area during the moistening process, followed by free water. The peak areas of non-flowing water, free water, and total water were correlated with the water content(P<0.01). Therefore, LF-NMR can quickly and non-destructively predict the water content of Arecae Semen during moistening. The peak area of non-flowing water and the content of free water were correlated with the content of arecoline in the soaking solution(P<0.01), which indicated that the faster flow of non-flowing water and more free water corresponded to more arecoline dissolved. The MRI images showed that the water migration pathway varied at different soaking temperatures, and the moistening degree obtained by this means was consistent with that obtained based on traditional experience. The rate constant K_1 fitted by Peleg model decreased with the increase in water temperature, while the capacity constant K_2 showed an opposite trend. The Arrhenius equation fitting of K_1 with temperature showed that the activation energy of Arecae Semen in the moistening process was 32.98 kJ·mol~(-1). LF-NMR/MRI can be used to analyze the water status and content and determine the end moisturing point of Arecae Semen. Peleg model can accurately describe the water absorption properties of Arecae Semen in the moistening process. The findings of this study can guide the moistening optimization and mechanism research of other seed Chinese medicinal materials.
Areca ; Arecoline/analysis* ; Drugs, Chinese Herbal/analysis* ; Kinetics ; Seeds/chemistry* ; Water/analysis*

Animals ; Arecoline ; pharmacology ; Cholinergic Agonists ; pharmacology ; Female ; Guinea Pigs ; In Vitro Techniques ; Male ; Muscle Contraction ; drug effects ; Muscle, Smooth ; physiology ; Pyloric Antrum ; physiology ; Receptor, Muscarinic M3 ; metabolism

The regulation mechanism of arecoline on rat hepatic CYP2E1 was studied in vivo. After oral administration of arecoline hydrobromide (AH; 4, 20 and 100 mg x kg(-1) x d(-1)) to rats for one week, the hepatic CYP2E1 mRNA level remained unchanged, but the hepatic CYP2E1 protein content was dose-dependently increased. Additionally, although the hepatic CYP2E1 activity was induced by AH treatment, the induction was attenuated with the increase in dosage. The results indicate that the effect of arecoline on rat hepaticdoes not involve transcriptional activation of the gene, but largely involves the stabilization of CYP2E1 protein against degradation or increased efficiency of CYP2E1 mRNA translation, and additionally involve the post- ranslational modification of CYP2E1 protein. Furthermore, the CYP2E1 response is fairly equal among the different species, the induction of rat hepatic CYP2E1 by arecoline suggests that there is a risk of metabolic interaction among the substrate drugs of CYP2E1 in betel-quid use human.
Animals ; Arecoline ; pharmacology ; Cytochrome P-450 CYP2E1 ; metabolism ; Cytochrome P-450 CYP2E1 Inducers ; pharmacology ; Humans ; Liver ; drug effects ; metabolism ; RNA, Messenger ; Rats

OBJECTIVETo investigate the origin of myofibroblasts in oral submucous fibrosis.

METHODSThe oral keratinocytes and fibroblasts were isolated and cultured. The expression of the alpha-smooth muscle actin in the fibroblasts was examined by immunohistochemistry and reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTSNo difference was found in expression of alpha-smooth muscle actin between the fibroblasts that were directly stimulated by arecoline and the control. The expression of alpha-smooth muscle actin in the keratinocyte and fibroblast-cocultured group was higher than in the control group, and higher in fibroblasts cocultured with keratinocytes preprocessed by arecoline than in fibroblasts cocultured with keratinocytes without preprocessed by arecoline.

CONCLUSIONSThe differentiation of myofibroblasts from fibroblasts in oral submucous fibrosis might be induced by the interaction of arecoline and keratinocyte.

Actins ; metabolism ; Arecoline ; pharmacology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Coculture Techniques ; Fibroblasts ; cytology ; metabolism ; Humans ; Keratinocytes ; cytology ; Mouth Mucosa ; cytology ; Oral Submucous Fibrosis ; metabolism ; pathology

BACKGROUNDThe rapidly activating delayed rectifier potassium current (I(Kr)), whose pore-forming alpha subunit is encoded by the human ether-a-go-go-related gene (hERG), is a key contributor to the third phase of action potential repolarization. The aim of this study was to investigate the effect and mechanism of arecoline hydrobromide induced inhibition of hERG K(+) current (I(hERG)).

METHODSTransient transfection of hERG channel cDNA plasmid pcDNA3.1 into the cultured HEK293 cells was performed using Lipofectamine. A standard whole-cell patch-clamp technique was used to record the I(hERG) before and after the exposure to arecoline.

RESULTSArecoline decreased the amplitude and the density of the I(hERG) in a concentration-dependent manner (IC(50) = 9.55 mmol/L). At test potential of +60 mV, the magnitude of I(hERG) tail at test pulse of -40 mV was reduced from (151.7 ± 6.2) pA/pF to (84.4 ± 7.6) pA/pF (P < 0.01, n = 20) and the magnitude of I(hERG) tail at test pulse of -110 mV was reduced from (-187.5 ± 9.8) pA/pF to (-97.6 ± 12.6) pA/pF (P < 0.01, n = 20). The blockade of arecoline in the open and inactivated state was significant in a state-dependent manner. The maximal blockade was achieved in the inactivated state. Studies of gating mechanism showed that the steady-state activation curve of I(hERG) was significantly negatively shifted by arecoline. Time constants of activation were shortened. Steady-state inactivation curve and time constants of fast inactivation were not significantly affected by arecoline. Furthermore, the inhibition of I(hERG) by arecoline was characterized markedly by a frequency-dependent manner from 0.03 to 1.00 Hz pulse.

CONCLUSIONArecoline could potently block I(hERG) in both frequency and state-dependent manner.

Action Potentials ; drug effects ; Arecoline ; pharmacology ; Dose-Response Relationship, Drug ; ERG1 Potassium Channel ; Ether-A-Go-Go Potassium Channels ; antagonists & inhibitors ; physiology ; HEK293 Cells ; Humans