Genetic toxicology and toxicokinetics of arecoline and related areca nut compounds: an updated review

Analysis of areca alkaloids and their conversions using CE-C4D and identification by CE-MS

As one of the four major addictive substance globally, areca nut contains areca alkaloids as its principal active ingredients, which exhibit both medicinal potential and toxic effects. In this study, a concise and effective approach was developed for the simultaneous analysis of areca alkaloids using laboratory-built capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (C4D). The proposed method demonstrated satisfactory linearity (R2 ≥ 0.995), precision (RSDs ≤ 6.56%) and quantification limits of 0.77-1.37 μM. This method has been successfully used to quantify areca products with recoveries of 92.2-110.1%. In addition, the effect of processing on the areca alkaloid content in areca nut-containing products was analyzed. On this basis, the conversions of areca alkaloids under various alkaline conditions were investigated through experimental studies and theoretical calculations. The separation parameters for CE-C4D were effectively transferred to CE-mass spectrometry (MS), and the above analytical results for areca alkaloids were validated by incorporating CE-MS related experiments.

Curcumin Alleviates Arecoline-induced Oral Submucous Fibrosis via the FOSL1/MAPK8 Axis

Oral submucous fibrosis (OSF) is a precancerous lesion of the oral cavity. Areca nut consumption can cause OSF through sustained activation of buccal mucosal fibroblasts (BMFs). This study explored the effect of curcumin on arecoline-induced BMF activation and its mechanism of action. BMFs were isolated and identified by immunofluorescence detection of fibroblast surface markers vimentin and S100A4. After transfection with FOSL1- or MAPK8-related vectors, BMFs were activated by arecoline and treated with curcumin. Scratch and transwell assays were performed to detect cell migration. ChIP and luciferase reporter assays were conducted to detect the binding of FOSL1 to the MAPK8 promoter. RT-qPCR was used to detect FOSL1 and MAPK8 mRNA expression. Western blotting was used to detect FOSL1, MAPK8, COL1A1, α-SMA, Smad2, and p-Smad2 proteins. Curcumin treatment inhibited arecoline-induced fibroblast migration, reduced the expression of myofibroblast markers COL1A1, α-SMA, and p-Smad2, and downregulated the expression of FOSL1 and MAPK8. FOSL1 or MAPK8 overexpression enhanced migration and increased COL1A1, α-SMA, and p-Smad2 expression in curcumin-treated cells. FOSL1 bound to the MAPK8 promoter and promoted MAPK8 expression. Simultaneous FOSL1 overexpression and MAPK8 knockdown, compared to FOSL1 overexpression, reduced cell migration and inhibited COL1A1, α-SMA, and p-Smad2 expression. In conclusion, curcumin targets FOSL1 to reduce MAPK8 expression, thereby suppressing arecoline-induced fibroblast activation.

Inhibitory role of arecaidine on PPARγ signaling in oral mucosa: Mechanistic insights from transcriptome and experimental analysis

OBJECTIVE

This study aims to elucidate the effects of arecaidine on oral mucosa through RNA sequencing (RNA-Seq) combined with in vivo and in vitro experimental validation.

METHODS

Based on transcriptomic analysis, we preliminarily explored the molecular targets and mechanisms by which arecaidine influences oral mucosa. Subsequent validation was performed using arecaidine-treated human primary oral mucosal fibroblasts.

RESULTS

In vivo experiments revealed that the arecaidine-treated group exhibited significantly restricted oral cavity opening compared to the control group, with markedly reduced mouth-opening values. Histopathological analysis via HE staining and Masson staining demonstrated fibrotic lesions in the arecaidine-treated group. RNA-Seq libraries constructed from oral mucosal tissues identified 100 significantly differentially expressed genes (DEGs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses indicated that arecaidine influenced multiple pathways, including autoimmune thyroid disease, allograft rejection, type I diabetes, graft-versus-host disease, and the PPAR-γ signaling pathway. Notably, arecaidine significantly downregulated PPAR-γ, PCK1, pdk4, plin5, Hmgcs2, UCP3, and Angptl4, while upregulating TGF-β1, FOS, and other genes associated with the PPAR pathway. In vitro experiments confirmed that arecaidine induced substantial damage to fibroblasts, suppressing proliferation and promoting the secretion of inflammatory cytokines (e.g., IL-6, TGF-β, TNF-α) after 48 h exposure to high concentrations. Furthermore, arecaidine significantly altered the expression of molecules linked to the PPAR-γ signaling pathway.

CONCLUSION

This study delineates the transcriptomic response of oral mucosa to arecaidine through integrated in vivo and in vitro experiments, confirming its role in inducing submucosal fibrosis. The underlying mechanism is associated with dysregulation of the PPAR-γ signaling pathway.

Combined effect of areca nut, cigarettes, alcohol and SNPs in glycosyltransferase family genes on lung cancer development in Hainan, China

BACKGROUND

Abnormal glycosylation modification is closely related to the development and metastasis of cancers. As a carcinogen by the International Agency for Research on Cancer (IARC) of the WHO, areca nut lacked of combined effect' study with genetic factors related to lung cancer. The aim of this study was to investigate the combined effect of polymorphisms of glycosyltransferase family genes and behavioral factors on the susceptibility of lung cancer.

METHODS

A case‒control study was conducted in Hainan, which included 428 patients with lung cancer and 428 cancer-free controls. Six single-nucleotide polymorphisms (SNPs) (FUT2 rs1047781, rs601338, FUT3 rs28362459, rs3745635, ST6Gal-I rs2239611 and MGAT5 rs34944508) were detected by the MassARRAY System. The association between these SNPs and the risk of lung cancer, clinicopathological characteristics, and combined effect of behavioral factors (areca nuts, cigarettes, alcohol) and genotypes on lung cancer were estimated using by logistic regression analysis.

RESULTS

In this study, individuals with AA genotype in ST6Gal-I rs2239611 significantly increased lung cancer risk (ORadj = 2.077; 95%CI:1.191-3.624; Padj = 0.010), particularly in smokers (Padj = 0.038) and alcohol consumers (Padj = 0.049). FUT2 rs1047781 was associated with clinical stage (Padj = 0.047) and lymph node metastasis (Padj = 0.014). Significant gene-environment interactions were observed between behavioral factors (cigarette smoking, alcohol drinking, and betel quid chewing) and both FUT2 rs1047781 (Padj = 0.013) and ST6Gal-I rs2239611 (Padj = 0.047), collectively elevating lung cancer risk.

CONCLUSION

ST6Gal-I rs2239611 was a potential genetic biomarker for lung cancer. Areca nut chewing, cigarette smoking, alcohol drinking interacts with glycosyltransferase gene polymorphisms (FUT2 rs1047781 and ST6Gal-I rs2239611), increasing lung cancer risk-a novel finding given the lack of prior studies on this combination.

Effect of areca nut extracts on growth performance, slaughtering performance, and meat quality of broiler chickens

Introduction

Since the comprehensive ban on the addition of antibiotics to livestock and poultry feeds in China, the search for safe and natural antibiotic substitutes has become a hot spot in the animal breeding industry. Areca catechu L (AN), known as the leader among the four southern medicinal herbs, possesses functions such as insecticidal, antibacterial, antiinflammatory, promoting gastrointestinal motility and preventing Alzheimer's disease. Nevertheless, ANE is rarely used as a feed additive in AA broilers, and its specific role remains unclear. This study was conducted to investigate the effects of different levels of areca nut extracts (ANE) on growth performance, slaughter performance and meat quality of AA broiler chickens.

Methods

128 one-day-old Arbor Acres broilers were randomly divided into eight groups of 16 birds each, housed in three cages with 5-6 birds per cage, with or without ANE supplementation (0, 100, 150, 200, 250, 300, 350, and 400 mg/kg, respectively).

Results

The entire experiment duration was 49 days. Adding 100 and 200 mg/kg ANE to the diet could significantly increase the body weight of broilers at 21 days of age (P ≤ 0.001), and significantly reduce the feed-to-weight ratio from 1 to 21 days of age (P ≤ 0.001). The diet supplemented with 200 mg/kg ANE could significantly increase the average body weight at 49 days of age (P = 0.001). Compared with the control group, the addition of different dosages of ANE in the feed could improve the pH45min, yellowness, and shear force (P ≤ 0.043) of the pectoral and leg muscles of broilers. Additionally, the contents of crude fat and crude protein, which are nutritional components in the pectoral and leg muscles of the ANE-supplemented groups, were to an extent higher than those of the control group (P ≤ 0.036). The addition of different levels of ANE in the diet significantly raised the expression levels of muscle development-related genes, including Myf5, Myf6, MyoD1, IGF-1, and IGF-2 (P ≤ 0.032).

Discussion

In conclusion, An appropriate amount of ANE in the diet has been demonstrated to boost the growth performance and meat quality of broilers, facilitate muscle development, and has no remarkable influence on slaughter performance. the ideal dosage for broilers is 100-200 mg/kg ANE. The findings of this study offer valuable insights into the potential benefits of ANE in poultry production, and provide a basis for further research into the development of ANE as a new feed additive.

Association of SNPs in nAChRs genes, areca nut chewing and smoking, and their interaction with lung cancer in Hainan, China: a case control study

BACKGROUND

Areca nut (AN) was classified as a carcinogen by the International Agency for Research on Cancer (IARC) of the WHO in 2003. AN has the same carcinogenic components as cigarettes, such as benzo[a]pyrene (B[a]P) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), but its effects on interactions with genetic factors related to lung cancer have rarely been investigated.  METHODS: Here, a propensity score-matched case‒control study was conducted in Hainan, which included 445 patients with lung cancer and 445 cancer-free controls. Then, the associations between single-nucleotide polymorphisms (SNPs) in the CHRNA5-CHRNA3-CHRNB4 gene cluster and their interaction effects with AN chewing and smoking on lung cancer were analyzed. In addition, we explored the associations among AN, cigarettes, and genes related to lung cancer using the Comparative Toxicogenomics Database (CTD).

RESULTS

The results indicate that the CHRNA3 rs938682 (A > G) GG genotype (OR = 0.669, 95% CI = 0.454 ~ 0.984, P = 0.042) can decrease the risk of lung cancer. The CHRNB4 rs7178270 (C > G) GG genotype (OR = 1.729, 95% CI = 1.168 ~ 2.571, P = 0.006) can increase the risk of lung cancer. The CHRNA5 rs17486278 CC genotype was associated with a high risk in males, smokers, and drinkers. The CHRNA3 rs938682 GG genotype was associated with a low risk in AN chewers. The CHRNB4 rs7178270 GG genotype was associated with high risk in drinkers and AN chewers. CHRNB4 rs7178270 and AN chewing have an interaction effect on lung cancer in Hainan.

CONCLUSIONS

This study is the first to elucidate the hidden impacts of AN on lung cancer and provides a key evidence regarding the interactive effects of AN and cigarettes with SNPs in nAChRs genes on lung cancer.

Comparative analysis of Ki-67, α-SMA, and MMP-9 expression in oral submucous fibrosis and oral leukoplakia with/without dysplasia: Insights into malignant transformation mechanisms

BACKGROUND

The present study aimed to comparatively analyze the immunoexpression of Ki-67, Alpha Smooth Muscle Actin (α-SMA), and Matrix Metalloproteinase-9 (MMP-9) between Oral Leukoplakia (OL) and Oral Submucous Fibrosis (OSMF), both with and without dysplasia. The objective was to determine the potential role of these biomarkers in the diagnosis and prognostication of oral potentially malignant disorders (OPMDs) and their potential as targets for interventions.

MATERIALS AND METHODS

Immunohistochemical staining for Ki-67, α-SMA, and MMP-9 was performed on seventy formalin-fixed paraffin-embedded tissue blocks, comprising normal buccal mucosa (n=10), OSMF (n=30), and OL (n=30) with 15 cases each of dysplasia and non-dysplasia. The expression of these markers was comparatively evaluated in OSMF and OL, with and without dysplasia.

RESULTS

The immunoexpression of Ki-67, MMP-9, and α-SMA was found to be significantly higher (p<0.001) in OSMF compared to OL for the respective dysplastic counterparts. Additionally, OSMF with dysplasia exhibited a significantly higher expression (p<0.001) of these markers compared to OSMF without dysplasia.

CONCLUSIONS

The present study reports differences in cell proliferation rates, myofibroblast and MMP-9 expression between OSMF and OL. The higher expression of these markers in OSMF with dysplasia suggests accelerated disease progression and enhanced potential for transformation into oral squamous cell carcinoma (OSCC). These findings highlight variations in the tissue microenvironment of OPMDs, influencing their biological behaviour and prognosis.

Assessing the carcinogenic potential and molecular mechanisms of arecoline in human lungs: from in silico methods to in vitro validation

OBJECTIVE

Despite the globally recognized carcinogenic potential of arecoline, the primary active compound in areca nut, the molecular mechanisms underlying its role in lung adenocarcinoma (LUAD) have yet to be fully understood. This study aims to bridge this gap by integrating network toxicology, molecular docking and dynamics simulation, tumor bioinformatics, and in vitro assays to elucidate the molecular mechanisms through which arecoline contributes to LUAD development.

METHODS

We first utilized disease-related databases and compound databases to identify arecoline-targeted LUAD-relevant proteins and constructed an interaction network using Cytoscape to screen core proteins based on topological analysis. Subsequently, we performed molecular docking and dynamics simulation, along with surface plasmon resonance assay to examine and validate the interactions between arecoline and core proteins. Next, we utilized these proteins for functional enrichment analyses to explore their correlation with cancer. Ultimately, we detected the expression and prognosis of core genes and constructed a prognostic model to examine its relationship with immune infiltration and immunotherapy.

RESULTS

Arecoline targets 106 LUAD-relevant proteins, including 24 core proteins. The stable interactions of arecoline and core proteins (especially PTGS2) greatly support the carcinogenic toxicity of arecoline in human lungs. These target proteins influence the occurrence, progression, and immune infiltration of LUAD by participating in pathways related to cancer and immunity, thereby affecting the prognosis and immunotherapy of LUAD patients.

CONCLUSION

This study elucidates the molecular mechanism underlying arecoline-induced LUAD, introducing a novel approach for assessing food safety and presenting innovative and promising targets and strategies for cancer intervention and therapy.

Unveiling the Mystery of the Stimulatory Effects of Arecoline: Its Relevance to the Regulation of Neurotransmitters and the Microecosystem in Multi-Ecological Intestinal Sites

The dried ripe seeds and pericarp of Areca catechu L., a palm species, possess significant economic value. Masticating betel nut is also a long-standing and widely prevalent lifestyle habit rooted in history, known for its stimulating effect. This effect stems primarily from arecoline, the principal active compound in betel nut. This study investigates the potential mechanisms underlying the stimulating effects of arecoline, focusing on neurotransmitters, neurotrophic factors, and the microecosystem in multi-ecological intestinal sites. After arecoline intervention in mice, significant changes were observed in locomotor activity. The levels of dopamine (DA) in liver tissue and 5-hydroxytryptamine (5-HT) in brain tissue were significantly reduced. There was a significant increase in microbial activity in the feces and in the level of n-valeric acid in the intestinal content. At the genus level, the relative abundance of Clostridium was significantly reduced, whereas the relative abundances of Helicobacter and Aquincola were markedly increased. Helicobacter, Aquincola, Faecalibaculum, and Liquorilactobacillus were signature genera in the arecoline-treated group. The 5-HT level was significantly negatively correlated with the abundance of the signature genera Aquincola, Helicobacter, and Liquorilactobacillus in the arecoline group. The ingestion of arecoline can alter the behavioral patterns of mice, causing significant changes in the 5-HT levels in brain tissue and exerting regulatory effects on the microecosystem in multi-ecological intestinal sites. These findings will provide a reference for the future development and utilization of betel nut.

Epigallocatechin-3-gallate inhibits the collagen accumulation of oral submucous fibrosis induced by arecoline

Objective

Oral submucous fibrosis (OSF) is a chronic oral mucosal disease, which exerts a profound impact on patients' daily life and currently lacks efficacious therapeutic interventions. Epigallocatechin-3-gallate (EGCG), the abundant polyphenol found in green tea, exhibits remarkable anti-fibrotic effects on the skin. However, the research on OSF regarding EGCG is relatively limited.

Purpose

We aimed to investigate the potential therapeutic effect of EGCG against OSF using an arecoline (ARE) -induced rat model and primary rat oral fibroblasts.

Methods

Primary rat oral mucosal fibroblasts (ROMF) were isolated and identified. Optimal ARE concentrations were established using the Cell Counting Kit-8. The impact of ARE on extracellular matrix (ECM)-related protein expression was assessed through RT-qPCR and Western blot techniques. Similarly, the effects of EGCG on ARE-induced ECM changes in ROMF were evaluated. The study also established an OSF model in Sprague-Dawley rats, induced by ARE, with pathological changes characterized using HE and Masson's staining, further assessing the impact of ARE on ECM-related protein expression in rat oral tissues through RT-qPCR and Western blot methods.

Results

EGCG effectively suppressed the ARE-induced ECM components while concurrently improving the OSF pathological process in vitro and in vivo.

Conclusion

The results indicate that the natural product EGCG effectively suppressed the increased ECM components induced by ARE and concurrently improved the OSF pathological process, indicating that EGCG could be potentially a novel anti-fibrotic candidate drug for the treatment of OSF.

Recent Advance on Biological Activity and Toxicity of Arecoline in Edible Areca (Betel) Nut: A Review

Areca nut (Areca catechu L. AN), which is the dried, mature seed of the palm species Areca catechu L., is consumed by over 600 million individuals, predominantly in South Asia, East Africa, and certain regions of the tropical Pacific. The International Agency for Research on Cancer (IARC) has classified it as a species carcinogenic to humans and designated it as a Group 1 human carcinogen. Arecoline, which has attracted attention for its therapeutic potential in the treatment of mental illness and the relief of gastrointestinal disorders, is the main active alkaloid in the areca nut. However, in 2020, the IARC said that arecoline might be a "probable human carcinogen". Arecoline can cause various types of cellular damage, primarily leading to the destruction of cell morphology, reduced survival rates, abnormal physiological functions, and even cell apoptosis. The research on its toxic mechanisms includes several aspects, such as increased levels of reactive oxygen species, autophagy, epigenetic dysregulation, and immune dysfunction, but these research findings are scattered and lack systematic integration. This article summarizes the effect mechanisms of arecoline on the oral cavity, neurological and cardiovascular systems, and other organs, as well as embryogenesis, and provides detailed and valuable insights for the clinical practice and targeted therapy of arecoline.

Exposure assessment to areca alkaloids in the Chinese populations through areca nut chewing

Chewing areca nuts is popular in China. Areca alkaloids are the major toxic compounds in areca nuts. In this study, the levels of four areca alkaloids (i.e. arecoline, arecaidine, guvacoline and guvacine) in 119 areca nut samples were analyzed and 3030 areca nut consumption questionnaires were collected to investigate the exposure to areca alkaloids in the Chinese populations through areca nut chewing. The levels of arecoline, arecaidine, guvacoline and guvacine in different areca nut products were 0.46-4.97 mg/g, 0.57-7.51 mg/g, 0.08-1.44 mg/g and 0.03-8.48 mg/g, respectively. Chewing fresh areca fruits was the main source of arecoline and the total areca alkaloids exposure. The estimated daily intake (EDI) of arecoline and the total areca alkaloids for the Chinese populations were 1.126 and 2.625 mg/kg BW/day for average exposure, 4.411 and 9.739 mg/kg BW/day for high exposure (P95th). The EDI varied with age and gender. The young male population (≤ 34 years) had the highest EDI than other populations. Concentrated and focused efforts are required to educate the general public, especially the young male population, about the risks of areca nut chewing to reduce exposure to areca alkaloids of the Chinese population.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-024-05966-6.

Anti-Neuroinflammatory Potential of Areca Nut Extract and Its Bioactive Compounds in Anthracene-Induced BV-2 Microglial Cell Activation

Particulate matter (PM2.5) containing polycyclic aromatic hydrocarbons (PAHs) is of considerable environmental importance worldwide due to its adverse effects on human health, which are associated with neurodegenerative diseases (NDDs). Areca catechu L. (AC) fruit is known to possess various pharmacological properties; however, the anti-neuroinflammatory roles of AC on the suppression of PAH-induced neuroinflammation are still limited. Thus, we focused on the effects and related signaling cascades of AC and its active compounds against anthracene-induced toxicity and inflammation in mouse microglial BV-2 cells. Phytochemicals in the ethanolic extract of AC (ACEE) were identified using LC-MS, and molecular docking was conducted to screen the interaction between compounds and target proteins. Significant bioactive compounds in ACEE such as arecoline, (-)-epicatechin, and syringic acid were evinced through the LC-MS spectrum. The docking study revealed that (-)-epicatechin showed the highest binding affinities against NF-κB. For cell-based approaches, anthracene induced intracellular ROS, mRNA levels of TNF-α, IL-1β, and IL-6, and the release of TNF-α through enhancing JNK, p38, and NF-κB signaling pathways. However, the co-treatment of cells with ACEE or (-)-epicatechin could reverse those anthracene-induced changes. The overall study suggested that ACEE-derived bioactive compounds such as (-)-epicatechin may be developed as a potential anti-neuroinflammatory agent by preventing inflammation-mediated NDDs.

Oxidative Stress, Oxidative Damage, and Cell Apoptosis: Toxicity Induced by Arecoline in Caenorhabditis elegans and Screening of Mitigating Agents

As the areca nut market is expanding, there is a growing concern regarding areca nut toxicity. Areca nut alkaloids are the major risky components in betel nuts, and their toxic effects are not fully understood. Here, we investigated the parental and transgenerational toxicity of varied doses of areca nut alkaloids in Caenorhabditis elegans. The results showed that the minimal effective concentration of arecoline is 0.2-0.4 mM. First, arecoline exhibited transgenerational toxicity on the worms' longevity, oviposition, and reproduction. Second, the redox homeostasis of C. elegans was markedly altered under exposure to 0.2-0.4 mM arecoline. The mitochondrial membrane potential was thereafter impaired, which was also associated with the induction of apoptosis. Moreover, antioxidant treatments such as lycopene could significantly ameliorate the toxic effects caused by arecoline. In conclusion, arecoline enhances the ROS levels, inducing neurotoxicity, developmental toxicity, and reproductive toxicity in C. elegans through dysregulated oxidative stress, cell apoptosis, and DNA damage-related gene expression. Therefore, the drug-induced production of reactive oxygen species (ROS) may be crucial for its toxic effects, which could be mitigated by antioxidants.

Inhibition of cortical synaptic transmission, behavioral nociceptive, and anxiodepressive-like responses by arecoline in adult mice

Areca nut, the seed of Areca catechu L., is one of the most widely consumed addictive substances in the world after nicotine, ethanol, and caffeine. The major effective constituent of A. catechu, arecoline, has been reported to affect the central nervous system. Less is known if it may affect pain and its related emotional responses. In this study, we found that oral application of arecoline alleviated the inflammatory pain and its induced anxiolytic and anti-depressive-like behavior. Arecoline also increased the mechanical nociceptive threshold and alleviated depression-like behavior in naïve mice. In the anterior cingulate cortex (ACC), which acts as a hinge of nociception and its related anxiety and depression, by using the multi-electrode field potential recording and whole-cell patch-clamp recording, we found that the evoked postsynaptic transmission in the ACC of adult mice has been inhibited by the application of arecoline. The muscarinic receptor is the major receptor of the arecoline in the ACC. Our results suggest that arecoline alleviates pain, anxiety, and depression-like behavior in both physiological and pathological conditions, and this new mechanism may help to treat patients with chronic pain and its related anxiety and disorder in the future.

Comprehensive insights into areca nut: active components and omics technologies for bioactivity evaluation and quality control

Areca nut (AN), the fruit or seed of Areca catechu Linn, has many uses, including chewing and medicinal purposes. It has sparked worries about health due to the presence of alkaloids. Chewing AN may have a variety of negative consequences; however, the medicinal use of AN has no notable adverse effects. To completely understand and effectively use AN, researchers have investigated its chemical makeup or biological activity, analyzed the variations between different AN species and different periods, and improved extraction and processing procedures. Today, an increasing number of researchers are exploring the underlying reasons for AN variations, as well as the molecular mechanisms of biosynthesis of chemical components, to comprehend and change AN at the genetic level. This review presents an overview of the clinical study, pharmacology, and detection of the main bioactive components in AN, and the main factors influencing their content, delving into the omics applications in AN research. On the basis of the discussions and summaries, this review identifies current research gaps and proposes future directions for investigation.

Arecoline promotes Akt-c-Myc-driven aerobic glycolysis in esophageal epithelial cells

Aerobic glycolysis is a typical metabolic rearrangement for tumorigenesis. Arecoline is of explicit carcinogenicity, numerous works demonstrate its mutagenicity, genotoxicity, and cytotoxicity. However, the effects of arecoline on aerobic glycolysis of esophageal epithelial cells remain unclear. In the present study, 5 μM arecoline efficiently increased HK2 expression to induce aerobic glycolysis in Het-1A-Are and NE2-Are cells. The mechanistic analysis showed that arecoline activated the Akt-c-Myc signaling pathway and reduced the GSK3β-mediated phosphorylation of c-Myc on Thr58 to prevent its ubiquitination and destruction, subsequently promoting HK2 transcription and expression. Taken together, these results suggest that arecoline can induce aerobic glycolysis of esophageal epithelial cells and further confirm that arecoline is a carcinogen harmful to human health.

Fibroblast activating protein promotes the proliferation, migration, and activation of fibroblasts in oral submucous fibrosis

OBJECTIVES

Fibroblast activating protein (FAP) is associated with various organ fibrosis. However, the expression and molecular function of FAP in oral submucous fibrosis (OSF) is still unclear.

MATERIALS AND METHODS

The high-performance liquid chromatography was used to detect the presence of alkaloids in areca nut extract (ANE). Real-time qPCR, Western blot, and Immunohistochemistry assay were used to analyze the expression of FAP mRNA or protein in OSF and normal oral tissue. A chi-squared test analyzed the relationship between FAP protein expression and clinicopathological data of OSF patients. CCK-8, Wound-healing, and Transwell migration assay were employed to assess the effect of the proliferation and migration ability of hOMF cells with FAP overexpression or knockdown. The expression level of a-SMA, FSP1, and P13K-Akt signaling pathways-related protein in hOMF cells transfected with FAP overexpression or knockdown plasmid was verified by western blot assay.

RESULTS

The four specific areca alkaloids (Arecoline, Guvacine, Arecaidine, and Guvacoline) were successfully detected in the ANE. The viability of hOMF cells was significantly improved in the 50 μg/mL ANE group and was inhibited in the 5 and 50 mg/mL ANE groups. The expression of FAP was upregulated in OSF tissues, and hOMF cells treated with 50 μg/mL ANE and was related to pathology grade, clinical stage, and history of chewing betel nut. Additionally, FAP may promote the proliferation, migration, and activation of hOMF cells through the P13K-Akt signaling pathway.

CONCLUSIONS

This study found that ANE had a bidirectional effect on the viability of hOMF cells, and the FAP gene was a potential therapeutic target in OSF.

Arecoline-Induced Hepatotoxicity in Rats: Screening of Abnormal Metabolic Markers and Potential Mechanisms

Arecoline is a pyridine alkaloid derived from areca nut in the Arecaceae family. It has extensive medicinal activity, such as analgesic, anti-inflammatory, and anti-allergic. However, the toxicity of Arecoline limits its application. Most current studies on its toxicity mainly focus on immunotoxicity, carcinogenesis, and cancer promotion. However, there are few systematic studies on its hepatotoxicity and mechanisms. Therefore, this research explored the mechanism of hepatotoxicity induced by Arecoline in rats and analyzed endogenous metabolite changes in rat plasma by combining network toxicology with metabolomics. The differential metabolites after Arecoline exposure, such as D-Lysine, N4-Acetylaminobutanal, and L-Arginine, were obtained by metabolomics study, and these differential metabolites were involved in the regulation of lipid metabolism, amino acid metabolism, and vitamin metabolism. Based on the strategy of network toxicology, Arecoline can affect the HIF-1 signaling pathway, MAPK signaling pathway, PI3K-Akt signaling pathway, and other concerning pathways by regulating critical targets, such as ALB, CASP3, EGFR, and MMP9. Integration of metabolomics and network toxicology results were further analyzed, and it was concluded that Arecoline may induce hepatotoxicity by mediating oxidative stress, inflammatory response, energy and lipid metabolism, and cell apoptosis.

Jiawei Danxuan Koukang Alleviates Arecoline Induced Oral Mucosal Lesions: Network Pharmacology and the Combined Ultra-High Performance Liquid Chromatography (UPLC) and Mass Spectrometry (MS)

Purpose

Arecoline is one of the main toxic components of arecoline to cause oral mucosal lesions or canceration, which seriously affects the survival and life quality of patients. This study analyzed the mechanism of Jiawei Danxuan Koukang (JDK) in alleviating arecoline induced oral mucosal lesions, to provide new insights for the treatment of oral submucosal fibrosis (OSF) or cancerosis.

Methods

Metabolomics was applied to analyze the composition of JDK and serum metabolites. The active ingredients of JDK were analyzed by the combined ultra-high performance liquid chromatography and mass spectrometry. The target network of JDK, metabolites and OSF was analyzed by network pharmacology, and molecular docking. Oral mucosal lesions and fibrosis were analyzed by HE and Masson staining. Cell differentiation, proliferation and apoptosis were detected. The expressions of α-SMA, Collagen I, Vimentin, Snail, E-cadherin, AR and NOTCH1 were detected by Western blot.

Results

Arecoline induced the gradual atrophy and thinning of rat oral mucosal, collagen accumulation, the increase expressions of fibrosis-related proteins and Th17/Treg ratio. JDK inhibited arecoline-induced oral mucosal lesions and inflammatory infiltration. Arecoline induced changes of serum metabolites in Aminoacyl-tRNA biosynthesis, Alanine, aspartate and glutamate metabolism and Arginine biosynthesis pathways, which were reversed by M-JDK. Quercetin and AR were the active ingredients and key targets of JDK, metabolites and OSF interaction. Arecoline promoted the expression of AR protein, and the proliferation of oral fibroblasts. Quercetin inhibited the effect of arecoline on oral fibroblasts, but was reversed by AR overexpression. Arecoline induced NOTCH1 expression in CAL27 and SCC-25 cells, and promoted cell proliferation, but was reversed by M-JDK or quercetin.

Conclusion

JDK improved the arecoline-induced OSF and serum metabolite functional pathway. Quercetin targeted AR protein to improve arecoline-induced OSF. JDK and quercetin inhibited arecoline-induced NOTCH1 protein expression in CAL27 and SCC-25 cells to play an anti-oral cancer role.

Phyllanthus emblica fruits: a polyphenol-rich fruit with potential benefits for oral management

The fruit of Phyllanthus emblica Linn., which mainly grows in tropical and subtropical regions, is well-known for its medicine and food homology properties. It has a distinctive flavor, great nutritional content, and potent antioxidant, anti-inflammatory, anti-cancer and immunoregulatory effects. According to an increasing amount of scientific and clinical evidence, this fruit shows significant potential for application and development in the field of oral health management. Through the supplementation of vitamins, superoxide dismutase (SOD) and other nutrients reduce virulence expression of various oral pathogens, prevent tissue and mucosal damage caused by oxidative stress, etc. Phyllanthus emblica fruit can promote saliva secretion, regulate the balance of the oral microecology, prevent and treat oral cancer early, promote alveolar bone remodeling and aid mucosal wound healing. Thus, it plays a specific role in the prevention and treatment of common oral disorders, producing surprising results. For instance, enhancing the effectiveness of scaling and root planing in the treatment of periodontitis, relieving mucosal inflammation caused by radiotherapy for oral cancer, and regulating the blood glucose metabolism to alleviate oral discomfort. Herein, we systematically review the latest research on the use of Phyllanthus emblica fruit in the management of oral health and examine the challenges and future research directions based on its chemical composition and characteristics.

Antibacterial mechanism of areca nut essential oils against Streptococcus mutans by targeting the biofilm and the cell membrane

Introduction

Dental caries is one of the most common and costly biofilm-dependent oral diseases in the world. Streptococcus mutans is the major cariogenic pathogen of dental caries. S. mutans synthesizes extracellular polysaccharides by autologous glucosyltransferases, which then promotes bacterial adhesion and cariogenic biofilm formation. The S. mutans biofilm is the principal target for caries treatment. This study was designed to explore the antibacterial activity and mechanisms of areca nut essential oil (ANEO) against S. mutans.

Methods

The ANEOs were separated by negative pressure hydro-distillation. The Kirby-Bauer method and broth microdilution method were carried out to evaluate the antibacterial activity of different ANEOs. The antibacterial mechanism was revealed by crystal violet staining, XTT reduction, microbial adhesion to hydrocarbon test, extracellular polysaccharide production assay, glucosyltransferase activity assay, lactate dehydrogenase leaking, propidium iodide staining and scanning electron microscopy (SEM). The cytotoxicity of ANEOs was determine by MTT assay.

Results

The ANEOs separated at different temperatures exhibited different levels of antibacterial activity against S. mutans, and the ANEO separated at 70°C showed the most prominent bacteriostatic activity. Anti-biofilm experiments showed that the ANEOs attenuated the adhesion ability of S. mutans by decreasing the surface hydrophobicity of the bacteria, prevented S. mutans biofilm formation by inhibiting glucosyltransferase activity, reducing extracellular polysaccharide synthesis, and reducing the total biofilm biomass and activity. SEM further demonstrated the destructive effects of the ANEOs on the S. mutans biofilm. Cell membrane-related experiments indicated that the ANEOs destroyed the integrity of the cell membrane, resulting in the leakage of lactic dehydrogenase and nucleic acids. SEM imaging of S. mutans cell showed the disruption of the cellular morphology by the ANEOs. The cytotoxicity assay suggested that ANEO was non-toxic towards normal oral epithelial cells.

Discussion

This study displayed that ANEOs exerted antibacterial activity against S. mutans primarily by affecting the biofilm and disrupting the integrity of the cell membrane. ANEOs has the potential to be developed as an antibacterial agent for preventing dental caries. Additionally, a new method for the separation of essential oil components is presented.

Assessment of Areca Nut Bioactivities in Western Diet-Induced Mice NAFLD Model

The areca nut is often consumed as a chewing food in the Asian region. Our previous study revealed that the areca nut is rich in polyphenols with high antioxidant activity. In this study, we further assessed the effects and molecular mechanisms of the areca nut and its major ingredients on a Western diet-induced mice dyslipidemia model. Male C57BL/6N mice were divided into five groups and fed with a normal diet (ND), Western diet (WD), WD with areca nut extracts (ANE), areca nut polyphenols (ANP), and arecoline (ARE) for 12 weeks. The results revealed that ANP significantly reduced WD-induced body weight, liver weight, epididymal fat, and liver total lipid. Serum biomarkers showed that ANP ameliorated WD-enhanced total cholesterol and non-high-density lipoprotein (non-HDL). Moreover, analysis of cellular signaling pathways revealed that sterol regulatory element-binding protein 2 (SREBP2) and enzyme 3-hydroxy-3-methylglutaryld coenzyme A reductase (HMGCR) were significantly downregulated by ANP. The results of gut microbiota analysis revealed that ANP increased the abundance of beneficial bacterium Akkermansias and decreased the abundance of the pathogenic bacterium Ruminococcus while ARE shown the opposite result to ANP. In summary, our data indicated that areca nut polyphenol ameliorated WD-induced dyslipidemia by increasing the abundance of beneficial bacteria in the gut microbiota and reducing the expressions of SREBP2 and HMGCR while areca nut ARE inhibited this improvement potential.

The Controversial Roles of Areca Nut: Medicine or Toxin?

Areca nut (AN) is used for traditional herbal medicine and social activities in several countries. It was used as early as about A.D. 25-220 as a remedy. Traditionally, AN was applied for several medicinal functions. However, it was also reported to have toxicological effects. In this review article, we updated recent trends of research in addition to acquire new knowledge about AN. First, the history of AN usage from ancient years was described. Then, the chemical components of AN and their biological functions was compared; arecoline is an especially important compound in AN. AN extract has different effects caused by different components. Thus, the dual effects of AN with pharmacological and toxicological effects were summarized. Finally, we described perspectives, trends and challenges of AN. It will provide the insight of removing or modifying the toxic compounds of AN extractions for enhancing their pharmacological activity to treat several diseases in future applications.

Oral Submucous Fibrosis: Etiological Mechanism, Malignant Transformation, Therapeutic Approaches and Targets

Oral submucosal fibrosis (OSF) is a chronic, progressive and potentially malignant oral disorder with a high regional incidence and malignant rate. With the development of the disease, the normal oral function and social life of patients are seriously affected. This review mainly introduces the various pathogenic factors and mechanisms of OSF, the mechanism of malignant transformation into oral squamous cell carcinoma (OSCC), and the existing treatment methods and new therapeutic targets and drugs. This paper summarizes the key molecules in the pathogenic and malignant mechanism of OSF, the miRNAs and lncRNAs with abnormal changes, and the natural compounds with therapeutic effects, which provides new molecular targets and further research directions for the prevention and treatment of OSF.

Protective effect of the newly synthesized and characterized charge transfer (CT) complex against arecoline induced toxicity in third-instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg9: experimental and theoretical mechanistic insights

Agents that suppress the toxic effect of arecoline (a chemical present in the Areca nut fruit) have become a need of the hour owing to its several harmful effects on human beings. Although some drug molecules have been developed for this purpose, yet, simple, easy to prepare, and economical molecules with remarkable potency are still a challenge to design. The present work thus becomes important as it involves the synthesis of a new charge transfer complex (CTC) material, which has, for the first time, been screened to investigate its effect on the toxic effects of arecoline. The newly designed material (CL), which is generated from the reaction between 2,4,6-trinitrophenol (TNP) and pyrazole (PYZ), has been crystallized by a slow evaporation method and characterized by employing spectral studies including single crystal X-ray crystallography. Spectrophotometry studies with the inclusion of the Benesi-Hildebrand equation reveal 1 : 1 stoichiometry and physical parameters of CL. Assays were used for determining the protective effect of CL against arecoline. CL was found to (dose-dependently) decrease β-galactosidase activity, damage in tissue and DNA damage caused by arecoline (80 μM) in the third-instar larvae of the transgenic Drosophila melanogaster (hsp70-lacZ)Bg⁹. The possible mechanism of this effect was explored through fluorescence and UV-vis spectroscopy. The possibility of suppression of arecoline action on the muscarinic acetylcholine receptor 1-G11 protein complex (found in the cell membrane) in the presence of CL was studied theoretically by molecular docking. Density functional theory (DFT) also theoretically supported various aspects of the designed material concerning the energy profile of the orbitals (HOMO-LUMO) as well as the energy minimized structure. Furthermore, time dependent (TD) DFT corroborated the electronic properties of the designed material.

Genetic and epigenetic instability induced by betel quid associated chemicals

Over the years, betel quid chewing and tobacco use have attracted considerable interest as they are implicated as the most likely causative risk factors of oral and esophageal cancers. Although areca nut use and betel quid chewing may lead to apoptosis, chronic exposure to areca nut and slaked lime may promote pre-malignant and malignant transformation of oral cells. The putative mutagenic and carcinogenic mechanisms may involve endogenous nitrosation of areca and tobacco alkaloids as well as the presence of direct alkylating agents in betel quid and smokeless tobacco. Metabolic activation of carcinogenic N-nitrosamines by phase-I enzymes is required not only to elicit the genotoxicity via the reactive intermediates but also to potentiate the mutagenicity with the sporadic alkylations of nucleotide bases, resulting in the formation of diverse DNA adducts. Persistent DNA adducts provides the impetus for genetic and epigenetic lesions. The genetic and epigenetic factors cumulatively influence the development and progression of disorders such as cancer. Accumulation of numerous genetic and epigenetic aberrations due to long-term betel quid (with or without tobacco) chewing and tobacco use culminates into the development of head and neck cancers. We review recent evidence that supports putative mechanisms for mutagenicity and carcinogenicity of betel quid chewing along with tobacco (smoking and smokeless) use. The detailed molecular mechanisms of the extent of accumulation and patterns of genetic alterations, indicative of the prior exposure to carcinogens and alkylating agents because of BQ chewing and tobacco use, have not yet been elucidated.

In Vitro Antioxidant Activity of Areca Nut Polyphenol Extracts on RAW264.7 Cells

Chewing areca nuts is a popular hobby in the Asian region, and areca nuts are rich in polyphenols, although some alkaloids are included. In this study, we explored the antioxidant activity of areca nut polyphenols (ANP) in lipopolysaccharides (LPS)-stimulated RAW264.7 cells. The results revealed that ANP reduced the level of reactive oxygen species (ROS) in LPS-stimulated RAW264.7 cells and enhanced the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1). RNA-seq analysis showed that ANP down-regulated the transcription of genes related to the cancer pathway at 160 μg/mL, and the inflammatory pathway as well as viral infection pathway at 320 μg/mL. The cellular signaling analysis further revealed that the expressions of these genes were regulated by the mitogen-activated protein kinase (MAPK) pathway, and ANP downregulated the activation of the MAPK signaling pathway stimulated by LPS. Collectively, our findings showed that ANP inhibited the MAPK pathway and activated the Nrf2/HO-1 antioxidant pathways to reduce ROS generation induced by LPS.

Roles of selected non-P450 human oxidoreductase enzymes in protective and toxic effects of chemicals: review and compilation of reactions

This is an overview of the metabolic reactions of drugs, natural products, physiological compounds, and other (general) chemicals catalyzed by flavin monooxygenase (FMO), monoamine oxidase (MAO), NAD(P)H quinone oxidoreductase (NQO), and molybdenum hydroxylase enzymes (aldehyde oxidase (AOX) and xanthine oxidoreductase (XOR)), including roles as substrates, inducers, and inhibitors of the enzymes. The metabolism and bioactivation of selected examples of each group (i.e., drugs, "general chemicals," natural products, and physiological compounds) are discussed. We identified a higher fraction of bioactivation reactions for FMO enzymes compared to other enzymes, predominately involving drugs and general chemicals. With MAO enzymes, physiological compounds predominate as substrates, and some products lead to unwanted side effects or illness. AOX and XOR enzymes are molybdenum hydroxylases that catalyze the oxidation of various heteroaromatic rings and aldehydes and the reduction of a number of different functional groups. While neither of these two enzymes contributes substantially to the metabolism of currently marketed drugs, AOX has become a frequently encountered route of metabolism among drug discovery programs in the past 10-15 years. XOR has even less of a role in the metabolism of clinical drugs and preclinical drug candidates than AOX, likely due to narrower substrate specificity.

N-acetyl cysteine prevents arecoline-inhibited C2C12 myoblast differentiation through ERK1/2 phosphorylation

Arecoline is known to induce reactive oxygen species (ROS). Our previous studies showed that arecoline inhibited myogenic differentiation and acetylcholine receptor cluster formation of C2C12 myoblasts. N-acetyl-cysteine (NAC) is a known ROS scavenger. We hypothesize that NAC scavenges the excess ROS caused by arecoline. In this article we examined the effect of NAC on the inhibited myoblast differentiation by arecoline and related mechanisms. We found that NAC less than 2 mM is non-cytotoxic to C2C12 by viability analysis. We further demonstrated that NAC attenuated the decreased number of myotubes and nuclei in each myotube compared to arecoline treatment by H & E staining. We also showed that NAC prevented the decreased expression level of the myogenic markers, myogenin and MYH caused by arecoline, using immunocytochemistry and western blotting. Finally, we found that NAC restored the decreased expression level of p-ERK1/2 by arecoline. In conclusion, our results indicate that NAC attenuates the damage of the arecoline-inhibited C2C12 myoblast differentiation by the activation/phosphorylation of ERK. This is the first report to demonstrate that NAC has beneficial effects on skeletal muscle myogenesis through ERK1/2 upon arecoline treatment. Since defects of skeletal muscle associates with several diseases, NAC can be a potent drug candidate in diseases related to defects in skeletal muscle myogenesis.

Arecoline promotes proliferation and migration of human HepG2 cells through activation of the PI3K/AKT/mTOR pathway

Background

Arecoline is a well-known risk factor for oral submucosal fibrosis and cancer. However, the mechanistic correlation between arecoline and hepatocellular cancer remains elusive. Here, we investigated the effect of arecoline on the proliferation and migration of human HepG2 hepatoma cells and its potential oncogenic mechanisms.

Methods

Bioinformatic technologies were used to identify the deferentially expressed miRNAs (DE-miRNAs) and hub target genes of arecoline-induced cancers. These DE-miRNAs, hub genes and pathway were proved in arecoline-treated HepG2 cells.

Results

A total of 86 DE-miRNAs and 460 target genes were identified. These target genes are associated with DNA-templated regulation of transcription and other biological processes. Significant molecular functions were protein binding, calcium ion binding, and enrichment in the nucleus and cytoplasm. These genes are involved in the PI3K-AKT pathway. CDK1, CCND1, RAF1, CDKN1B and BTRC were defined as the top 5 hub target genes, and patients with high expression of CDK1 showed poor prognosis. Compared with control group, 2.5 µM arecoline treatment increased the proliferation and migration ability of the HepG2 cells. Treatment with 2.5 µM arecoline increased the levels of miR-21-3p, miR-21-5p and miR-1267, upregulated the expression of PI3K-AKT pathway factors, CDK1, CCND1 but decreased RAF1 expression.

Conclusion

A low concentration arecoline can induce the proliferation and migration of HepG2 cells, with the potential mechanism of action linked to high levels of exosomal miR-21 and miR-1267, activation of the PI3K-AKT pathway, upregulation of CDK1 and CCND1, and downregulation of RAF1.

Arecoline Is Associated With Inhibition of Cuproptosis and Proliferation of Cancer-Associated Fibroblasts in Oral Squamous Cell Carcinoma: A Potential Mechanism for Tumor Metastasis

Background

Metastatic disease remains the primary cause of death in patients with oral squamous cell carcinoma (OSCC), especially those who use betel nut. The different steps of the metastatic cascade rely on reciprocal interactions between cancer cells and the tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs) are regarded as a significant component in the TME of OSCC. However, the precise mechanisms regulating CAFs in OSCC are poorly understood.

Methods

Thirteen genes related to the arecoline were analyzed to explore the significant ones involved in arecoline-related OSCC metastasis. The GSE139869 (n = 10) and The Cancer Genome Atlas (TCGA)-OSCC data (n = 361) were mined for the identification of the differentially expressed genes. The least absolute shrinkage and selection operator (LASSO) regression was performed to identify the independent prognostic signatures. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted to explore the functional enrichment of selected genes, and gene set enrichment analysis of cuproptosis-related genes was completed. Spearman’s analysis and Tumor Immune Estimation Resource (TIMER) were used to visualize the correlation between the infiltration of CAFs and the gene expression. The correlation analysis of the cells and different genes, including CAF infiltration and transcripts per million expression, was assessed. The relationship between arecoline and CAFs was confirmed by cell counting kit-8 assay (CCK-8). CancerSEA was searched to identify the single-cell phenotype.

Result

Arecoline-associated fibrosis-related OSCC differentially expressed genes (AFOC-DEGs), namely, PLAU, IL1A, SPP1, CCL11, TERT, and COL1A2, were screened out and selected from the Gene Expression Omnibus (GEO) database and TCGA database. AFOC-DEGs were highly expressed in OSCC, which led to poor survival of patients. Functional enrichment analysis, protein–protein interaction network construction, and Spearman’s correlation analysis all suggested that AFOC-DEGs were closely associated with cuproptosis. Cellular experiments demonstrated that arecoline stimulation could significantly increase the cell viability of CAFs. Single-sample Gene Set Enrichment Analysis (ssGSEA) results showed that GLS and MTF1 were highly expressed when fibroblasts proliferated at high enrichment levels. In addition, analysis of single-cell sequencing results suggested that OSCC cells with high expression of AFOC-DEGs were associated with OSCC metastasis.

Conclusion

We found a close association between arecoline, cuproptosis, and CAFs, which might play an important role in the metastasis of OSCC.

Improvement of autophagic flux mediates the protection of hydrogen sulfide against arecoline-elicited neurotoxicity in PC12 cells

Arecoline, the most abundant alkaloid of the areca nut, induces toxicity to neurons. Hydrogen sulfide (H₂S) is an endogenous gas with neuroprotective effects. We recently found that arecoline reduced endogenous H₂S content in PC12 cells. In addition, exogenously administration of H₂S alleviated the neurotoxicity of arecoline on PC12 cells. Increasing evidence has demonstrated the neuroprotective role of improvement of autophagic flux. Therefore, the aim of the present work is to explore whether improvement of autophagic flux mediates the protection of H₂S against arecoline-caused neurotoxicity. Transmission electron microscope (TEM) for observation of ultrastructural morphology. Western blotting was used to detect protein expression of the related markers. Functional analysis contained LDH release assay, Hoechst 33,258 nuclear staining and flow cytometry were used to detect cytotoxicity and apoptosis. In the present work, we found that arecoline disrupted autophagy flux in PC12 cells as evidenced by accumulation of autophagic vacuoles, increase in LC3II/LC3I, and upregulation of p62 expression in PC12 cells. Notably, we found that sodium hydrosulfide (NaHS), the donor of H₂S improved arecoline-blocked autophagy flux in PC12 cells. Furthermore, we found that blocking autophagic flux by chloroquine (CQ), the inhibitor of autophagy flux, antagonized the inhibitory role of NaHS in arecoline-induced cytotoxicity apoptosis and endoplasmic reticulum (ER) stress. In conclusion, H₂S improves arecoline-caused disruption of autophagic flux to exert its protection against the neurotoxicity of arecoline.

Betel Nut Chewing Is Associated with the Risk of Kidney Stone Disease

(1) Background: Betel nut chewing injures bodily health. Although, the relationship between betel nut chewing and kidney stone disease (KSD) is unknown. (2) Methods: We analyzed 43,636 men from Taiwan Biobank. We divided them into two groups on the status of betel nut chewing, the never-chewer and ever-chewer groups. Self-reported diagnosed KSD was defined as the subject’s medical history of KSD in the questionnaire. Logistic regression was used to analyze the association of betel nut chewing and the risk of KSD. (3) Results: The mean age of subjects in the present study was 50 years, and 16% were ever-chewers. KSD was observed in 3759 (10.3%) and 894 (12.6%) participants in the group of never-chewer and ever-chewer groups, respectively. Higher risk of KSD was found in participants with betel nut chewing compared with to without betel nut chewing (odds ratio (OR), 1.094; 95% confidence interval (95% CI), 1.001 to 1.196). Furthermore, the daily amounts of betel nut chewing >30 quids was associated with a more than 1.5-fold increase (OR, 1.571; 95% CI, 1.186 to 2.079) in the odds of KSD; (4) Conclusions: Our study suggests that betel nut chewing is associated with the risk of KSD and warrants further attention to this problem.

Scarification and Seed Biomatriconditioning Effect Using Endophytic-Rhizobacteria in Areca Nut (Areca catechu L.) Seedling Vigor

&lt;b&gt;Background and Objective:&lt;/b&gt; Intensive and commercial development of areca nut requires the provision of high-vigour areca nut. This study aimed to evaluate the effect of scarification and seeds biomatriconditioning using endophytic-rhizobacteria in increasing seedlings vigor of areca nut. &lt;b&gt;Materials and Methods:&lt;/b&gt; The research was carried out at the Agronomy Unit of Agrotechnology Laboratory, Agriculture Faculty, Halu Oleo University, from November, 2020-March, 2021. The research design was split-plot in a Completely Randomized Design (CRD). The main plot, seed scarification, consisted of 2 treatments, without scarification and scarification. Sub-plots, seeds biomatriconditioning using endophytic-rhizobacteria, consisted of 6 treatments, control, L1-R, M5-R, LA6-R, LA2-E and RJ6-R. &lt;b&gt;Results:&lt;/b&gt; The results showed that the scarification treatment did not affect the seedlings vigor of the areca nut. Seed biomatriconditioning using endophytic-rhizobacteria was able to increase seedling vigor both without scarification and with scarification. There were 3 isolates of endophytic-rhizobacteria which were more able to increase the vigor of areca nut without scarification, namely L1-R, LA6-R and LA2-E, with an increase of 137, 104 and 102%, respectively compared to the control, while in scarified seeds, L1-R isolate was able to increase the seedlings vigor of areca nut by 194% compared to the control. &lt;b&gt;Conclusion:&lt;/b&gt; Scarification treatment did not affect the vigor of the areca nut. Seed biomatriconditioning with endophytic-rhizobacteria was able to increase the vigor of areca nut seeds either without scarification or with scarification.

Chemical Composition, Pharmacological, and Toxicological Effects of Betel Nut

Betel nut, the fruit of Areca catechu L, has a long medical history in Southeast Asia. It is native to Malaysia and is cultivated and processed extensively in subtropical regions, such as South China and India. Betel nut almost appears as a "snack" in various occasions in most parts of China. Clinically, betel nut can play a certain pharmacology role and was used in malaria, ascariasis, arthritis, enterozoic abdominalgia, stagnation of food, diarrhea, edema, and beriberi. The nervous excitement of betel nut chewing has made it gradually become popular. However, chewing betel nut can induce oral submucosal fibrosis (OSF) and oral cancer (OC). At the same time, long-term chewing of betel nut also causes inhaled asthma, sperm reducing, betel quid dependence (BQD), and uterine and esophageal cancers. The main components of processed betel nut are the goal of this review. This study will mainly start from the pharmacological activity and toxicology study of betel nut in recent years, aiming to seek its advantages and disadvantages. In the meantime, this study will analyze and emphasize that betel nut and arecoline are the high-risk factors for oral cancer, which should arouse attention and vigilance of the public.