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.

Exosomal miR-17-5p derived from epithelial cells is involved in aberrant epithelium-fibroblast crosstalk and induces the development of oral submucosal fibrosis.

Oral submucous fibrosis (OSF) is a chronic and inflammatory mucosal disease caused by betel quid chewing, which belongs to oral potentially malignant disorders. Abnormal fibroblast differentiation leading to disordered collagen metabolism is the core process underlying OSF development. The epithelium, which is the first line of defense against the external environment, can convert external signals into pathological signals and participate in the remodeling of the fibrotic microenvironment. However, the specific mechanisms by which the epithelium drives fibroblast differentiation remain unclear. In this study, we found that Arecoline-exposed epithelium communicated with the fibrotic microenvironment by secreting exosomes. MiR-17-5p was encapsulated in epithelial cell-derived exosomes and absorbed by fibroblasts, where it promoted cell secretion, contraction, migration and fibrogenic marker (α-SMA and collagen type I) expression. The underlying molecular mechanism involved miR-17-5p targeting Smad7 and suppressing the degradation of TGF-ß receptor 1 (TGFBR1) through the E3 ubiquitination ligase WWP1, thus facilitating downstream TGF-ß pathway signaling. Treatment of fibroblasts with an inhibitor of miR-17-5p reversed the contraction and migration phenotypes induced by epithelial-derived exosomes. Exosomal miR-17-5p was confirmed to function as a key regulator of the phenotypic transformation of fibroblasts. In conclusion, we demonstrated that Arecoline triggers aberrant epithelium-fibroblast crosstalk and identified that epithelial cell-derived miR-17-5p mediates fibroblast differentiation through the classical TGF-ß fibrotic pathway, which provided a new perspective and strategy for the diagnosis and treatment of OSF.

SIRT1-activating butein inhibits arecoline-induced mitochondrial dysfunction through PGC1α and MTP18 in oral cancer.

BACKGROUND: Mitochondrial dysfunction associated with mitochondrial DNA mutations, enzyme defects, generation of ROS, and altered oxidative homeostasis is known to induce oral carcinogenesis during exposure to arecoline. Butein, a natural small molecule from Butea monosperma, possesses anti-inflammatory, anti-diabetic, and anti-cancer effects. However, the role of butein in the mitochondrial quality control mechanism has not been illuminated clearly. PURPOSE: This study aimed to explore the role of butein in preserving mitochondrial quality control during arecoline-induced mitochondrial dysfunction in oral cancer to curtail the early onset of carcinogenesis. METHODS: Cell viability was evaluated by MTT assay. The relative protein expressions were determined by western blotting. Immunofluorescence and confocal imaging were used to analyze the relative fluorescence and co-localization of proteins. Respective siRNAs were used to examine the knockdown-based studies. RESULTS: Butein, in the presence of arecoline, significantly caused a decrease in mitochondrial hyperpolarization and ROS levels in oral cancer cells. Mechanistically, we found an increase in COXIV, TOM20, and PGC1α expression during butein treatment, and inhibition of PGC1α blunted mitochondrial biogenesis and decreased the mitochondrial pool. Moreover, the fission protein MTP18, and its molecular partners DRP1 and MFF were dose-dependently increased during butein treatment to maintain mitochondria mass. In addition, we also found increased expression of various mitophagy proteins, including PINK1, Parkin, and LC3 during butein treatment, suggesting the clearance of damaged mitochondria to maintain a healthy mitochondrial pool. Interestingly, butein increased the activity of SIRT1 to enhance the functional mitochondrial pool, and inhibition of SIRT1 found to reduce the mitochondrial levels, as evident from the decrease in the expression of PGC1α and MTP18 in oral cancer cells. CONCLUSION: Our study proved that SIRT1 maintains a functional mitochondrial pool through PGC1α and MTP18 for biogenesis and fission of mitochondria during arecoline exposure and could decrease the risk of mitochondria dysfunctionality associated with the onset of oral carcinogenesis.

Antifibrotic Effect of Baicalin on Arecoline Induced Human Oral Fibroblast: An In-Vitro Study.

BACKGROUND: Baicalin is a flavonoid obtained from the Chinese herb Scutellaria baicalensis, which has a wide varieties of health benefits and scope to be studied for its therapeutic potential in oral fibrosis. AIM: The aim of the study was to investigate the antifibrotic effect of a Baicalin in arecoline induced human oral fibroblast in vitro setting. MATERIAL AND METHODS: Arecoline and ethanolic extracts of Baicalin were commercially purchased from Sigma-Aldrich. Human oral fibroblasts were cultured and characterized with specific fibroblast markers, and cells were stimulated with arecoline. An MTT assay (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) was executed to determine the half-maximal inhibitory concentration of arecoline and Baicalin. Arecoline-induced cells (25µg/ml) were treated with a non-toxic dose of Baicalin (proliferative dose of 25µg/ml). Cytokine (CCL2, CXCL-8, IL17, IL-beta, and IL-6) and fibrotic marker genes were studied by reverse transcription-polymerase chain reaction (RT-PCR). The inhibitory effect of Baicalin was studied to prove its antifibrotic properties. RESULTS: Arecoline significantly upregulated all inflammatory and fibrotic markers. On treatment with 25µg/ml of Baicalin, all inflammatory and fibrotic markers were inhibited. Arecoline affects fibroblast morphology, supporting the fact that arecoline is cytotoxic to cells. CONCLUSION: Baicalin can be used as an antifibrotic herb to treat OSMF.

Simultaneous determination of five constituents of areca nut extract in rat plasma using UPLC-MS/MS and its application in a pharmacokinetic study.

Areca nuts have been used as a traditional Chinese medicine (TCM) for thousands of years. Recent studies have shown that it exhibits good pharmacological activity and toxicity. In this study, the pharmacokinetics of five major components of areca nut extract in rats were investigated using a highly sensitive ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-MS/MS) method. Arecoline, arecaidine, guvacoline, guvacine, and catechin were separated and quantified accurately using gradient elution with mobile phases of (A) water containing 0.1 % formic acid-10 mM ammonium formate, and (B) methanol. The constituents were detected under a timing switch between the positive and negative ion modes using multiple reaction monitoring (MRM). Each calibration curve had a high R2 value of >0.99. The method accuracies ranged -7.09-11.05 % and precision values were less than 14.36 %. The recovery, matrix effect, selectivity, stability, and carry-over of the method were in accordance with the relevant requirements. It was successfully applied for the investigation of the pharmacokinetics of these five constituents after oral administration of areca nut extract. Pharmacokinetic results indirectly indicated a metabolic relationship between the four areca nut alkaloids in rats. For further clarification of its pharmacodynamic basis, this study provided a theoretical reference.

Arecoline induces neurotoxicity in HT22 cells via the promotion of endoplasmic reticulum stress and downregulation of the Nrf2/HO-1 pathway.

Arecoline, the predominant bioactive substance extracted from areca nut (AN), is the world's fourth most frequently used psychoactive material. Research has revealed that chewing AN can affect the central nervous system (CNS) and may lead to neurocognitive deficits that are possibly linked to the action of arecoline. However, the mechanism behind the neurotoxicity caused by arecoline remains unclear. This study aimed to investigate the neurotoxic effects of arecoline and its underlying mechanism. The results showed that arecoline caused cytotoxicity against HT22 cells in a dose-dependent manner and induced apoptosis by upregulating the expression of pro-apoptotic caspase and Bcl-2 family proteins. Furthermore, arecoline escalated intracellular reactive oxygen species (ROS) levels and Ca2+ concentration with increasing doses, thereby motivating endoplasmic reticulum stress (ERS) and ERS-associated apoptotic protein expression. Additionally, the study found that arecoline attenuates intracellular antioxidant defense by inhibiting the translocation of NF-E2-related factor-2 (Nrf2) into the nucleus and decreasing downstream Heme oxygenase-1 (HO-1) levels. The specific inhibitor Sodium 4-phenylbutyrate (4-PBA) can dramatically attenuate arecoline-mediated cell apoptosis and ERS-associated apoptotic pathway expression by blocking ERS. The antioxidant N-Acetylcysteine (NAC) also effectively reverses the arecoline-mediated increase of ERS-related apoptotic pathway protein levels by scavenging intracellular ROS accumulation. In conclusion, this study suggests that arecoline induces neurotoxicity in HT22 cells via ERS mediated by oxidative stress- and Ca2+ disturbance, as well as by downregulation of the Nrf2/HO-1 pathway.

Aberrantly downregulated FENDRR by arecoline elevates ROS and myofibroblast activation via mitigating the miR-214/MFN2 axis.

Long non-coding RNA FENDRR possesses both anti-fibrotic and anti-cancer properties, but its significance in the development of premalignant oral submucous fibrosis (OSF) remains unclear. Here, we showed that FENDRR was downregulated in OSF specimens and fibrotic buccal mucosal fibroblasts (fBMFs), and overexpression of FENDRR mitigated various myofibroblasts hallmarks, and vice versa. In the course of investigating the mechanism underlying the implication of FENDRR in myofibroblast transdifferentiation, we found that FENDRR can directly bind to miR-214 and exhibit its suppressive effect on myofibroblast activation via titrating miR-214. Moreover, we showed that mitofusin 2 (MFN2), a protein that is crucial to the fusion of mitochondria, was a direct target of miR-214. Our data suggested that FENDRR was positively correlated with MFN2 and MFN2 was required for the inhibitory property of FENDRR pertaining to myofibroblast phenotypes. Additionally, our results showed that the FENDRR/miR-214 axis participated in the arecoline-induced reactive oxygen species (ROS) accumulation and myofibroblast transdifferentiation. Building on these results, we concluded that the aberrant downregulation of FENDRR in OSF may be associated with chronic exposure to arecoline, leading to upregulation of ROS and myofibroblast activation via the miR-214-mediated suppression of MFN2.

A conjugate vaccine strategy that induces protective immunity against arecoline.

Betel-quid chewing addiction is the leading cause of oral submucous fibrosis and oral cancer, resulting in significant socio-economic burdens. Vaccination may serve as a promising potential remedy to mitigate the abuse and combat accidental overdose of betel nut. Hapten design is the crucial factor to the development of arecoline vaccine that determines the efficacy of a candidate vaccine. Herein, we reported that two kinds of novel arecoline-based haptens were synthesized and conjugated to Bovine Serum Albumin (BSA) to generate immunogens, which generated antibodies with high affinity for arecoline but reduced binding for guvacoline and no affinity for arecaidine or guvacine. Notably, vaccination with Arec-N-BSA, which via the N-position on the tetrahydropyridine ring (tertiary amine group), led to a higher antibody affinity compared to Arec-CONH-BSA, blunted analgesia and attenuated hypothermia for arecoline.

Stromal thrombospondin 1 suppresses angiogenesis in oral submucous fibrosis.

A decline in mucosal vascularity is a histological hallmark of oral submucous fibrosis (OSF), a premalignant disease that is largely induced by betel quid chewing. However, the lack of available models has challenged studies of angiogenesis in OSF. Here, we found that the expression of thrombospondin 1 (THBS1), an endogenous angiostatic protein, was elevated in the stroma of tissues with OSF. Using a fibroblast-attached organoid (FAO) model, the overexpression of THBS1 in OSF was stably recapitulated in vitro. In the FAO model, treatment with arecoline, a major pathogenic component in areca nuts, enhanced the secretion of transforming growth factor (TGF)-ß1 by epithelial cells, which then promoted the expression of THBS1 in fibroblasts. Furthermore, human umbilical vein endothelial cells (HUVECs) were incorporated into the FAO to mimic the vascularized component. Overexpression of THBS1 in fibroblasts drastically suppressed the sprouting ability of endothelial cells in vascularized FAOs (vFAOs). Consistently, treatment with arecoline reduced the expression of CD31 in vFAOs, and this effect was attenuated when the endothelial cells were preincubated with neutralizing antibody of CD36, a receptor of THBS1. Finally, in an arecoline-induced rat OSF model, THBS1 inhibition alleviated collagen deposition and the decline in vascularity in vivo. Overall, we exploited an assembled organoid model to study OSF pathogenesis and provide a rationale for targeting THBS1.

PDE12 disrupts mitochondrial oxidative phosphorylation and mediates mitochondrial dysfunction to induce oral mucosal epithelial barrier damage in oral submucous fibrosis.

Oral submucous fibrosis (OSF) is a chronic oral mucosal disease. The pathological changes of OSF include epithelial damage and subepithelial matrix fibrosis. This study aimed to reveal the epithelial injury mechanism of OSF. A histopathological method was used to analyze oral mucosal tissue from OSF patients and OSF rats. The expression of PDE12 in the oral epithelium was analyzed by immunohistochemistry. The epithelial-mesenchymal transition (EMT) and tight junction proteins in arecoline-treated HOKs were explored by western blotting. Epithelial leakage was assessed by transepithelial electrical resistance and lucifer yellow permeability. The expression of PDE12 and the mitochondrial morphology, mitochondrial permeability transition pore opening, mitochondrial membrane potential, and mitochondrial reactive oxygen species (mtROS) were evaluated in arecoline-induced HOKs. Oxidative phosphorylation (OXPHOS) complexes and ATP content were also explored in HOKs. The results showed significant overexpression of PDE12 in oral mucosal tissue from OSF patients and rats. PDE12 was also overexpressed and aggregated in mitochondria in arecoline-induced HOKs, resulting in dysfunction of OXPHOS and impaired mitochondrial function. An EMT, disruption of tight junctions with epithelial leakage, and extracellular matrix remodeling were also observed. PDE12 overexpression induced by PDE12 plasmid transfection enhanced the mtROS level and interfered with occludin protein localization in HOKs. Interestingly, knockdown of PDE12 clearly ameliorated arecoline-induced mitochondrial dysfunction and epithelial barrier dysfunction in HOKs. Therefore, we concluded that overexpression of PDE12 impaired mitochondrial OXPHOS and mitochondrial function and subsequently impaired epithelial barrier function, ultimately leading to OSF. We suggest that PDE12 may be a new potential target against OSF.

Areca nut-induced oral fibrosis - Reassessing the biology of oral submucous fibrosis.

BACKGROUND: Oral submucous fibrosis (OSF) is a pathological condition characterized by excessive tissue healing resulting from physical, chemical, or mechanical trauma. Notably, areca nut consumption significantly contributes to the development of oral fibrosis. The current definition of OSF, recognizing its potential for malignant transformation, necessitates a more comprehensive understanding of its pathophysiology and etiology. HIGHLIGHTS: Areca nut induces fibrotic pathways by upregulating inflammatory cytokines such as TGF-ß and expressing additional cytokines. Moreover, it triggers the conversion of fibroblasts to myofibroblasts, characterized by α-SMA and γSMA expression, resulting in accelerated collagen production. Arecoline, a component of areca nut, has been shown to elevate levels of reactive oxygen species, upregulate the expression of various cytokines, and activate specific signaling pathways (MEK, COX2, PI3K), all contributing to fibrosis. Therefore, we propose redefining OSF as "Areca nut-induced oral fibrosis" (AIOF) to align with current epistemology, emphasizing its distinctive association with areca nut consumption. The refined definition enhances our ability to develop targeted interventions, thus contributing to more effective prevention and treatment strategies for oral submucous fibrosis worldwide. CONCLUSION: Arecoline plays a crucial role as a mediator in fibrosis development, contributing to extracellular matrix accumulation in OSF. The re-evaluation of OSF as AIOF offers a more accurate representation of the condition. This nuanced perspective is essential for distinguishing AIOF from other forms of oral fibrosis and advancing our understanding of the disease's pathophysiology.

Effectiveness of Ya-Samarn-Phlae in diabetic wound healing: Evidence from in vitro studies and a multicenter randomized controlled clinical trial.

ETHNOPHARMACOLOGICAL RELEVANCE: Ya-Samarn-Phlae (YaSP) has traditionally been widely used in southern Thailand for treating chronic and infected wounds, including diabetic foot ulcers. However, there are only a limited number of clinical studies supporting the use of this polyherbal formulation. Therefore, the present work aims to provide clinical evidence to support the application of YaSP, prepared according to a standardized traditional procedure (T-YaSP). Additionally, its potential chemical markers and wound healing-related biological activities were examined. MATERIALS AND METHODS: The in vitro wound healing-related biological activities of YaSP ethanol extract and T-YaSP, including antibacterial activity against Staphylococcus epidermidis, inhibition and eradication of staphylococcal biofilm, anti-inflammatory effects, and enhancement of human dermal fibroblast migration in scratch wounds, were examined using well-established protocols. The chemical profiles of the ethanol extract of YaSP and T-YaSP were compared, and with promising chemical markers, arecoline, alpha-mangostin, and curcumin were selected and quantified using the HPLC method. A prospective, multicenter, randomized, controlled, parallel-group study was conducted over 12 weeks to evaluate the efficacy of the YaSP solution as an adjunct therapy, combined with standard wound care, for diabetic ulcers compared to standard treatment. RESULTS: The YaSP extract reduces NO production and can scavenge NO radicals in LPS-induced RAW 264.7 macrophage cells. Additionally, in a scratch assay, this extract and one of its herbal components, Curcuma longa, enhance the migration of human dermal fibroblasts. T-YaSP, containing 2.412 ± 0.002 mg/g of arecoline, 2.399 ± 0.005 mg/g of curcumin, and 0.017 ± 0.000 mg/g of α-mangostin, has shown the ability to inhibit the development and eradicate the mature biofilm of S. epidermidis. The use of T-YaSP as an adjunct therapy led to a significantly higher proportion of patients achieving healing within six weeks compared to the standard treatment group (36%/9 patients vs. 4%/1 patient; p = 0.013). After 12 weeks, 19 out of 25 patients in the T-YaSP group experienced complete healing, whereas only four patients in the standard treatment group achieved complete wound healing (76% in the T-YaSP group vs. 16% in the control group; p < 0.001). CONCLUSION: The results presented here represent the first randomized controlled trial to demonstrate the effectiveness of the traditional polyherbal solution, T-YaSP, which exhibits a wide range of wound healing-related activities. Utilizing T-YaSP as an adjunctive treatment resulted in a significant improvement in the number of type 2 diabetic patients achieving complete healing. However, to explore and utilize YaSP further, conducting a double-blind, randomized controlled trial with a larger population is necessary.

Antifibrotic effect of silymarin on arecoline-induced fibrosis in primary human buccal fibroblasts: an in silico and in vitro analysis.

BACKGROUND: This study aimed to assess silymarin's anticancer and antifibrotic potential through in silico analysis and investigate its impact on in vitro arecoline-induced fibrosis in primary human buccal fibroblasts (HBF). METHODS & RESULTS: The study utilized iGEMDOCK for molecular docking, evaluating nine bioflavonoids, and identified silymarin and baicalein as the top two compounds with the highest target affinity, followed by subsequent validation through a 100ns Molecular Dynamic Simulation demonstrating silymarin's stable behavior with Transforming Growth Factor Beta. HBF cell lines were developed from tissue samples obtained from patients undergoing third molar extraction. Arecoline, a known etiological factor in oral submucous fibrosis (OSMF), was employed to induce fibrogenesis in these HBFs. The inhibitory concentration (IC50) of arecoline was determined using the MTT assay, revealing dose-dependent cytotoxicity of HBFs to arecoline, with notable cytotoxicity observed at concentrations exceeding 50µM. Subsequently, the cytotoxicity of silymarin was assessed at 24 and 72 h, spanning concentrations from 5µM to 200µM, and an IC50 value of 143µM was determined. Real-time polymerase chain reaction (qPCR) was used to analyze the significant downregulation of key markers including collagen, epithelial-mesenchymal transition (EMT), stem cell, hypoxia, angiogenesis and stress markers in silymarin-treated arecoline-induced primary buccal fibroblast cells. CONCLUSION: Silymarin effectively inhibited fibroblast proliferation and downregulated genes associated with cancer progression and EMT pathway, both of which are implicated in malignant transformation. To our knowledge, this study represents the first exploration of silymarin's potential as a novel therapeutic agent in an in vitro model of OSMF.

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 GSK3ß-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.

Anticancer activity of Bacopa monnieri through apoptosis induction and mitophagy-dependent NLRP3 inflammasome inhibition in oral squamous cell carcinoma.

BACKGROUND: Bacopa monnieri (BM) is traditionally used in human diseases for its antioxidant, anti-inflammatory and neuroprotective effects. However, its anticancer potential has been poorly understood. AIM: The aim of this study was to explore the detailed anticancer mechanism of BM against oral cancer and to identify the bioactive BM fraction for possible cancer therapeutics. RESULTS: We performed bioactivity-guided fractionation and identified that the aqueous fraction of the ethanolic extract of BM (BM-AF) had a potent anticancer potential in both in vitro and in vivo oral cancer models. BM-AF inhibited cell viability, colony formation, cell migration and induced apoptotic cell death in Cal33 and FaDu cells. BM-AF at low doses promoted mitophagy and BM-AF mediated mitophagy was PARKIN dependent. In addition, BM-AF inhibited arecoline induced reactive oxygen species production in Cal33 cells. Moreover, BM-AF supressed arecoline-induced NLR family pyrin domain containing 3 (NLRP3) inflammasome activation through mitophagy in Cal33 cells. The in vivo antitumor effect of BM-AF was further validated in C57BL/6J mice through a 4-nitroquinolin-1-oxide and arecoline-induced oral cancer model. The tumor incidence was significantly reduced in the BM-AF treated group. Further, data obtained from western blot and immunohistochemistry analysis showed increased expression of apoptotic markers and decreased expression of inflammasome markers in the tongue tissue obtained from BM-AF treated mice in comparison with the non-treated tumor bearing mice. CONCLUSION: In conclusion, BM-AF exhibited potent anticancer activity through apoptosis induction and mitophagy-dependent inhibition of NLRP3 inflammasome activation in both in vitro and in vivo oral cancer models. Moreover, we have investigated apoptosis and mitophagy-inducing compounds from this plant extract having anticancer activity against oral cancer cells.

The rapid antidepressant effect of acupuncture on two animal models of depression by inhibiting M1-Ach receptors regulates synaptic plasticity in the prefrontal cortex.

BACKGROUND: It is unclear whether acupuncture has a rapid antidepressant effect and what is the main mechanism. METHODS: In this study, forced swimming stress test (FST) in mice were divided into five groups: control group, acupuncture group, scopolamine group, arecoline group, and acupuncture + arecoline group. Chronic unpredictable mild stress (CUMS) model rats were divided into six groups: naïve (non-CUMS) group, CUMS group, acupuncture group, scopolamine group, arecoline group, and acupuncture + arecoline group. Twenty-four hours after the end of treatment, FST was conducted in mice and rats. The expression of M1-AchR, AMPA receptors (GluR1 and GluR2), BDNF, mTOR, p-mTOR, synapsin I, and PSD95 in the prefrontal cortex was determined by western blot. The spine density of neurons in the prefrontal cortex was detected by golgi staining. RESULTS: The results showed that acupuncture reduced the immobility time of FST in two depression models. Acupuncture inhibited the expression of M1-AchR and promoted the expression of GluR1, GluR2, BDNF, p-mTOR, synapsin I, PSD95, and increased the density of neuron dendritic spine in the prefrontal cortex. CONCLUSIONS: The rapid antidepressant effect of acupuncture may be activating the "glutamate tide" - AMPA receptor activation - BDNF release - mTORC1 pathway activation through inhibiting the expression of M1-AchR in the prefrontal cortex, thereby increasing the expression of synaptic proteins and regulating synaptic plasticity.

Therapeutic potential of sulforaphane: modulation of NRF2 mediated PI3/AKT/mTOR pathway in oral fibrosis / Potencial terapêutico do sulforafano: modulação do NRF-2 mediado o pela via PI3/AKT/mTOR na fibrose oral

Oral Submucous Fibrosis is a potentially malignant disorder caused by habitual areca nut chewing, which contributes to the dispersion of active alkaloids into subepithelial tissues, stimulating excessive extracellular matrix deposition. Various treatment modalities are available; however, their efficacy in inhibiting fibrosis progression remains limited. Sulforaphane (SFN), an isothiocyanate found abundantly in cruciferous plants, is known to have effective antifibrotic properties. Objective: The present study investigated the antifibrotic effect of SFN via phosphatidylinositol 3 kinase (PI3K), Serine/Threonine Kinase 1 (AKT-1), mammalian target of rapamycin (mTOR) pathway in arecoline (AER) induced fibrosis in human gingival fibroblasts [HGFs]. Material and Methods: MTT assay determined the half-maximal inhibitory concentration of AER and SFN at 24h in the HGF cell line. Expression levels of transforming growth factor ß1 (TGFß1), collagen type 1 alpha 2 (COL1A2), hydroxyproline (HYP), PI3, AKT, mTOR, and nuclear factor erythroid 2­related factor 2 (NRF2) were assessed post-AER and SFN treatment using qPCR and western blot analysis. Results: The findings of the study revealed that AER elicited a stimulatory effect, upregulating TGFß1, COL1A2, HYP, PI3K, AKT, and mTOR and downregulating NRF2 expression. Conversely, SFN treatment significantly upregulated NRF2, inhibiting TGFß1 mediated PI3/AKT/mTOR pathway. Conclusion: These observations suggest that SFN can be used as a promising synergistic antifibrotic agent to combat fibrogenesis via the non-Smad pathway (AU)

Fibrose submucosa oral é uma desordem potencialmente maligna causada pelo habito de mascar a noz da areca, o que contribui para a dispersão de alcalóides ativos nos tecidos subepiteliais, estimulando a deposição excessiva de matriz extracelular. Há várias modalidades terapêuticas, no entanto, com eficácia limitada no controle da progressão da fibrose. O sulforafano (SFN), isotiocianato encontrado abundantemente em plantas crucíferas, é conhecido por suas propriedades antifibróticas. Objetivo: Investigar os efeitos antifibróticos do SFN na via fosfatidilinositol3-quinase (PI3K), via quinase serina/treonina 1 (AKT-1), via do alvo da rapamicina em mamíferos (mTOR), na fibrose induzida por arecolina (AER) em fibroblastos gengivais de humanos (HGFs). Material e Métodos: A meia concentração inibitória mínima de AER e SFN em 24 horas nas células HGFs foi determinada por MTT. Os níveis de expressão de ß1 (TGFß1), colágeno tipo 1 alfa 2 (COL1A2), hidroxiprolina (HYP), PI3K, AKT, mTOR, fator nuclear eritroide 2 relacionado ao fator 2 (NRF2) foram analisados após tratamento com ERA e SFN através de qPCR e western blot. Resultados: O ERA apresentou efeito estimulatório aumentando a expressão de TGFß1, COL1A2, HYP, PI3K, AKT e mTOR e diminuindo a expressão de NRF2. Por outro lado, tratamento com SFN aumentou significativamente a expressão de NRF2, inibindo a liberação de TGFß1 mediada pela via PI3/AKT/mTOR. Conclusão: Esses achados sugerem que o SFN pode ser um agente antifibrótico promissor no combate à fibrogênese decorrente da via não-Smad (AU)

Integrated metabolomics and network pharmacology to reveal the mechanism of areca nut addiction.

As a chewing hobby, areca nut (Areca catechu L.) has become the most common psychoactive substance in the world, besides tobacco, alcohol and caffeinated beverages. Moreover, as a first-class carcinogen designated by International Agency for Research on Cancer, long-term chewing areca nut can result in oral mucosal diseases and even oral cancer. To clarify the potential mechanism of areca nut addiction, an integrated strategy of metabolomics and network pharmacology was adopted in this study. Network pharmacology study indicated that all the key targets related to areca nut addiction could be regulated by arecoline and pointed out the importance of G-protein coupled receptor signalling pathway. Analysis results of mice plasma metabolome and faeces metabolome intervened by arecoline suggested that the component may affect the dopamine system and 5-HT system by regulating phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, primary bile acid biosynthesis, glycerophospholipid metabolism and intestinal flora structure. Moreover, the potential importance of bile acids in formation of addictive behaviour of chewing areca nut was investigated by integrative analysis of the relationships between metabolites and intestinal flora. The study can provide scientific basis for the addiction intervention and treatment of areca nut chewers.

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.

Metastasis and immunosuppression promoted by mtDNA and PD-L1 in extracellular vesicles are reversed by WGP ß-glucan in oral squamous cell carcinoma.

The suppressive regulatory T cells (Treg) are frequently upregulated in cancer patients. This study aims to demonstrate the hypothesis that arecoline could induce the secretion of mitochondrial (mt) DNA D-loop and programmed cell death-ligand 1 (PD-L1) in extracellular vesicles (EVs), and attenuate T-cell immunity by upregulated Treg cell numbers. However, the immunosuppression could be reversed by whole glucan particle (WGP) ß-glucan in oral squamous cell (OSCC) patients. Arecoline-induced reactive oxygen specimen (ROS) production and cytosolic mtDNA D-loop were analyzed in OSCC cell lines. mtDNA D-loop, PD-L1, IFN-γ, and Treg cells were also identified for the surgical specimens and sera of 60 OSCC patients. We demonstrated that higher mtDNA D-loop, PD-L1, and Treg cell numbers were significantly correlated with larger tumor size, nodal metastasis, advanced clinical stage, and areca quid chewing. Furthermore, multivariate analysis confirmed that higher mtDNA D-loop levels and Treg cell numbers were unfavorable independent factors for survival. Arecoline significantly induced cytosolic mtDNA D-loop leakage and PD-L1 expression, which were packaged by EVs to promote immunosuppressive Treg cell numbers. However, WGP ß-glucan could elevate CD4+ and CD8+ T-cell numbers, mitigate Treg cell numbers, and promote oral cancer cell apoptosis. To sum up, arecoline induces EV production carrying mtDNA D-loop and PD-L1, and in turn elicits immune suppression. However, WGP ß-glucan potentially enhances dual effects on T-cell immunity and cell apoptosis and we highly recommend its integration with targeted and immune therapies against OSCC.