Fibrotic Effects of ArecolineN-Oxide in Oral Potentially Malignant Disorders

Abstract

The metabolites of environmental chemicals play key roles in carcinogenesis. Areca nut is strongly associated with the development of oral potentially malignant disorders (OPMD) or cancer. The main alkaloid in the areca nut is arecoline, which is highly cytotoxic and genotoxic. Arecoline N-oxide, a metabolite of areca nut alkaloids, which has been identified in animal urine, has been shown to induce mutagenicity in bacteria. In this study, it was found that its protein adduct could be detected in oral keratinocytes treated with areca nut extract. Increased collagen expression and severity of squamous hyperplasia were observed in arecoline N-oxide treated mice. In cultured oral fibroblasts, arecoline N-oxide showed stronger effects on the increase of fibrotic related genes including TGF-beta1, S100A4, MMP-9, IL-6, and fibronectin and a decrease of E-cadherin as compared with arecoline. Finally, arecoline N-oxide stimulation effectively increased the DNA damage marker, gamma-H2A.X, both in vitro and in vivo. Taken together, these results indicate that arecoline N-oxide shows a high potential for the induction of OPMD.

Arecoline, Hesperidin and Trifluoperazine-mediated Cytotoxicity and Cell Death Potential in NIH/3T3 Fibroblasts Cells –Toxicity/Safety Assessment in a NIH/3T3 Model Fibroblast Cell Line

“…3,4 Also, an in vivo study has demonstrated chromosome breakage. 5 Another report has documented that a related molecule (arecoline N-oxide) increased S100A4 (a member of the metastasis-related proteins in the calcium binding protein family and also used to identify cells of the fibroblast lineage) levels in cultured oral fibroblasts, 6 thereby substantiating the inclusion of this marker protein in this safety assessment study of ours. Also, this protein was found to be elevated in buccal fibroblasts in ex vivo 7 and in vitro studies.…”

Multifaceted Mechanisms of Areca Nuts in Oral Carcinogenesis: the Molecular Pathology from Precancerous Condition to Malignant Transformation

“…In the past few decades, accumulated studies have demonstrated that areca nuts can induce premalignant and malignant transformation of oral tissues. In animal model studies, areca nut extract (or the ingredient cocktail) can be an effective tumor initiator or promoter and can induce premalignant oral lesions, including submucosal fibrosis 9, 10 and squamous hyperplasia 11-13, or result in malignant transformation 13-16. For example, arecaidine displays a synergistic effect in the 7,12-dimethyl-benz(a)anthracene (DMBA)- induced tumor formation in the cheek pouch of hamster 15.…”

Arecoline N‐oxide regulates oral squamous cell carcinoma development through NOTCH1 and FAT1 expressions

“…TNF‐α induced NOTCH1 activation in cultured OSCC cells and regulates the cancer stem‐like cell phenotype and cell invasion (Lee, Ko, Warnakulasuriya et al, ; Yoshida et al, ). IL‐6 and TGF‐β1 stimulation are involved in the fibrotic effect in oral cells (Kuo et al, ; Tsai et al, ). Earlier findings revealed that the arecoline and areca nut ingredients are crucial in the pathogenesis of oral cancer (M. C. Chang et al, , ).…”

“…The cell lysate preparation and western blotting protocols were performed as previously described (Kuo et al, 2015). The primary antibodies used were: anti-phospho-histone H2A.X (Ser139; Cell Signaling Technology), anti-FMO3 (EPR6968; Abcam) and anti-GAPDH (GeneTex Inc., Hsinchu City, Taiwan).…”

“…Earlier findings from our lab indicated that ANO upregulates fibrotic gene expression and oral potentially malignant disorders (OPMD) severity in mice model. ANO‐mediated upregulation of caspase 8 expressions is involved in cell proliferation rather than apoptosis in the initial stage of oral tumorigenesis (P. Y. Chang et al, ; Kuo et al, ). These findings indicated that ANO might play a key role in areca nut induced carcinogenesis.…”