Arecoline-stimulated placenta growth factor production in gingival epithelial cells: modulation by curcumin

Arecoline aggravates acute ulcerative colitis in mice by affecting intestinal microbiota and serum metabolites

Arecoline is an alkaloid extracted from betel nut, which has various pharmacological effects. In the present study, we showed that arecoline aggravated experimental acute ulcerative colitis (UC) induced by dextran sodium sulfate (DSS) in mice. We measured body weight and colon length, evaluated disease activity index, colon pathology sections, and levels of colonic inflammatory factors. Arecoline exacerbated the clinical signs of UC and the colonic inflammatory response in mice. The results of 16S rRNA sequencing of fecal samples showed a significant decrease in the percentage of probiotic bacteria Ligilactobacillus, Limosilactobacillus and Lactobacillus and a significant increase in the percentage of conditionally pathogenic bacteria Odoribacter and Bacteroides after arecoline treatment. Serum untargeted metabolomics showed that arecoline intervention reduced the levels of ergothioneine, pentostatin, diadenosine tetraphosphate and other metabolites and modulated nicotinate and nicotinamide metabolism, metabolic pathways, glyoxylate and dicarboxylate metabolism, and other metabolic pathways of intestinal microorganisms. According to the combined microbial and metabolite analysis, arecoline influences metabolite levels by modulating the intestinal microbiota. In summary, it was found that arecoline treatment exacerbated colonic injury and intestinal inflammatory responses in UC mice, disrupted the host's intestinal flora, and affected changes in flora metabolites, thereby exacerbating the development of colonic inflammation. Therefore, the consumption of betel nut can be associated with the risk of aggravating UC.

The neutrophil elastase-upregulated placenta growth factor promotes the pathogenesis and progression of periodontal disease

BACKGROUND

Periodontal disease is a chronic inflammatory disease. Given its high prevalence, especially in aging population, the detailed mechanisms about pathogenesis of periodontal disease are important issues for study. Neutrophil firstly infiltrates to periodontal disease-associated pathogen loci and amplifies the inflammatory response for host defense. However, excessive neutrophil-secreted neutrophil elastase (NE) damages the affected gingival. In lung and esophageal epithelium, NE had been proved to upregulate several growth factors including placenta growth factor (PGF). PGF is an angiogenic factor with proinflammatory properties, which mediates the progression of inflammatory disease. Therefore, we hypothesize excessive NE upregulates PGF and participates in the pathogenesis and progression of periodontal disease.

METHODS

In gingival epithelial cells (GEC), growth factors array demonstrated NE-increased growth factors and further be corroborated by Western blot assay and ELISA. The GEC inflammation was evaluated by ELISA. In mice, the immunohistochemistry results demonstrated ligature implantation-induced neutrophil infiltration and growth factor upregulation. By multiplex assay, the ligature-induced proinflammatory cytokines level in gingival crevicular fluid (GCF) were evaluated. Finally, alveolar bone absorption was analyzed by micro-CT images and H & E staining.

RESULTS

NE upregulated PGF expression and secretion in GEC. PGF promoted GEC to secret IL-1β, IL-6, and TNF-α in GCF In periodontal disease animal model, ligature implantation triggered NE infiltration and PGF expression. Blockade of PGF attenuated the ligature implantation-induced IL-1β, IL-6, TNF-α and MIP-2 secretion and ameliorated the alveolar bone loss in mice.

CONCLUSION

In conclusion, the NE-induced PGF triggers gingival epithelium inflammation and promotes the pathogenesis and progression of periodontal disease.

Role of Plant Derived Alkaloids and Their Mechanism in Neurodegenerative Disorders

Neurodegenerative diseases are conventionally demarcated as disorders with selective loss of neurons. Conventional as well as newer molecules have been tested but they offer just symptomatic advantages along with abundant side effects. The discovery of more compelling molecules that can halt the pathology of these diseases will be considered as a miracle of present time. Several synthetic compounds are available but they may cause several other health issues. Therefore, natural molecules from the plants and other sources are being discovered to replace available medicines. In conventional medicational therapies, several plants have been reported to bestow remedial effects. Phytochemicals from medicinal plants can provide a better and safer alternative to synthetic molecules. Many phytochemicals have been identified that cure the human body from a number of diseases. The present article reviews the potential efficacy of plant-derived alkaloids, which possess potential therapeutic effects against several NDDs including Alzheimer's disease (AD), Huntington disease (HD), Parkinson's disease (PD), Epilepsy, Schizophrenia, and stroke. Alkaloids include isoquinoline, indole, pyrroloindole, oxindole, piperidine, pyridine, aporphine, vinca, β-carboline, methylxanthene, lycopodium, and erythrine byproducts. Alkaloids constitute positive roles in ameliorating pathophysiology of these illnesses by functioning as muscarinic and adenosine receptors agonists, anti-oxidant, anti-amyloid and MAO inhibitors, acetylcholinestrase and butyrylcholinesterase inhibitor, inhibitor of α-synuclein aggregation, dopaminergic and nicotine agonist, and NMDA antagonist.

The pharmacology, toxicology and potential applications of arecoline: a review

CONTEXT

Arecoline is an effective constituent of Areca catechu L. (Arecaceae) with various pharmacological effects. However, investigations also revealed that long use of arecoline could arouse some oral diseases.

OBJECTIVE

The present review gathers the fragmented information available in the literature (before 1 October 2015) regarding pharmacology and toxicology of arecoline. We also discussed the potential developments and applications of arecoline in the future.

METHODS

All the available information regarding the arecoline is compiled from scientific databases, including Science Direct, PubMed, Web of Science, Scopus, etc.

RESULTS

Previous research demonstrated that arecoline is one of the major effective constituents in A. catechu. Additionally, arecoline has a wide spectrum of pharmacological activities including effects on nervous, cardiovascular, digestive and endocrine systems and anti-parasitic effects. What's more, arecoline is reported to be the primary toxic constituent of A. catechu, and the main toxic effects include oral submucous fibrosis (OSF), oral squamous cell carcinoma (OSCC) and genotoxicity.

CONCLUSION

Arecoline has great potential to be a therapeutic drug for various ailments. However, further investigations are needed in the future to reduce or eliminate its toxicities before developing into new drug.

Elevated Lin28B expression is correlated with lymph node metastasis in oral squamous cell carcinomas

BACKGROUND

Lymph node (LN) metastasis is the most common cause of oral squamous cell carcinoma (OSCC)-related death. Searching the detailed molecular mechanisms involved LN metastasis in OSCC is still an open question.

METHODS

Paired tissue samples from tumor (T) and adjacent non-cancerous matched tissues (NCMT) parts, as well as LN metastatic lesions in patient with OSCC tissues were subjected to quantitative real-time PCR analysis for the expression levels of Lin28B. Arecoline, a major areca nut alkaloid, was to explore whether expression of Lin28B could be changed dose dependent in oral epithelial cells. Control and Lin28B-knockdown arecoline-stimulated oral epithelial cells were subjected to migration/invasion/anchorage-independent growth assay.

RESULTS

Compared with NCMT samples from the same OSCC patient, the expression of Lin28B was increased in all of the tumor samples. A similar upregulation of Lin28B was also observed in LN metastatic when compared with local tumors. Arecoline treatment dose dependently induced Lin28B expression in SG and FaDu cells. Lentiviral-mediated silencing Lin28B expression significantly attenuated arecoline-induced oncogenicity including proliferation, migration, invasiveness, and anchorage-independent growth in SG and FaDu cells.

CONCLUSIONS

Lin28B may be a useful biomarker and novel molecular target for LN metastasis OSCC patients' treatment.

Arecoline induces TNF-alpha production and Zonula Occludens-1 redistribution in mouse Sertoli TM4 cells

Background

Arecoline, a major alkaloid in Areca nut has the ability to induce oxidative stress. The effect of Areca nut, arecoline on reducing sperm quality and quantity were documented previously using several animal models. Junction disruption by down-regulation of the junction-adhesive protein via oxidative stress is an important route mediating abnormal spermatogenesis. Therefore, in this present study, we investigated the functional role of arecoline on junctional proteins.

Results

To analyze direct effects of arecoline on testis cells, confluent mouse testicular Sertoli cell line TM4 was exposed to arecoline. Arecoline decreased insoluble zonula occludens-1 (ZO-1) protein expression in TM4 cells, however, arecoline treatment increased TNF-alpha production in both TM4 and monocytic THP1 cells. In addition, ERK1/2 inhibitor PD98059 reversed arecoline effects on TNF-alpha and ZO-1.

Conclusions

Arecoline increases the production of TNF-alpha and induces protein redistribution of ZO-1. All these results explain the role of arecoline in male reproductive dysfunction, besides its cytotoxic induction.

Electronic supplementary material

The online version of this article (doi:10.1186/s12929-014-0093-z) contains supplementary material, which is available to authorized users.