Atherogenic effect of Arecoline: A computational study

Association between habitual betel quid chewing and risk of adverse cardiovascular outcomes: A systematic review

INTRODUCTION

Habitual betel quid chewing, a tobacco product, is a leading cause of oral cancer in Asia-Pacific countries where this practice is most prevalent. However, it is not well understood whether betel quid chewing is also a cause of adverse cardiovascular outcomes. To address this gap, we conducted a systematic literature review of peer-reviewed published studies evaluating the association between habitual betel quid use on the risk of adverse cardiovascular outcomes.

METHODS

We searched PubMed for studies assessing the correlation between betel quid chewing and cardiovascular health. We included studies if (i) they included human subjects; (ii) were peer-reviewed articles in indexed journals; and (iii) were in English. We extracted data from eligible studies and stratified them by geographical location, study designs and cardiovascular outcomes. Finally, we did a narrative synthesis of the data to identify adverse cardiovascular outcomes associated with chronic betel quid use.

FINDINGS

We reviewed data from 19 studies that met the inclusion criteria. Habitual betel quid chewing was associated with hypertension, atherosclerosis, inflammation and ischaemic heart disease. In addition, betel quid use was a risk factor for arrhythmias. Interestingly, betel quid use was an independent risk factor for cardiovascular disease in women. Long-term betel quid consumption was associated with higher risks for all-cause mortality and increased overall cardiovascular risk.

CONCLUSIONS

Habitual betel quid chewing is an important cardiovascular risk factor in populations where the practice is prevalent.

Systemic and Local Effects Among Patients With Betel Quid-Related Oral Cancer

The major predisposing factors of developing oral cancer include smoking, alcohol drinking, and betel quid chewing. Betel quid chewing could cause the abrasion and damage of oral mucosa by crude fibers, chemical insults by additive slaked lime, and arecoline from areca nut. These would lead to the local consequence of oral submucosal fibrosis, which is regarded clinically as a precancer lesion and a major cause of trismus. In addition, the components and additives in betel quid contain chemical toxins and carcinogens, which would further affect the oral mucosa and gradually develop a malignancy. Following literature review, aside from having a greater total tumor burden and more local diseases in the oral cavity and digestive tract, patients with betel quid-related oral cancer also have more systemic diseases from metabolic syndrome, hypertension, cardiovascular disease, type II diabetes mellitus, and obesity than those without this habit. In conclusion, those patients who have the history of smoking, alcohol drinking, and betel quid chewing would present much more unique clinical characteristics than those who only have a history of smoking and alcohol drinking. More attention should therefore be paid to pretreatment evaluation, treatment strategy, and posttreatment follow-up among betel quid chewers.

Potential Role of Host Microbiome in Areca Nut-Associated Carcinogenesis and Addiction

Areca nut (AN) is widely consumed all over the world, bringing great harm to human health and economy. Individuals with AN chewing are at high risk of cardiovascular disease and impaired immune system and metabolic system. Despite a growing number of studies having reported on the adverse effects brought by AN chewing, the exact mechanism of it is limited and the need for additional exploration remains. In recent years, the interaction between microorganisms, especially intestinal microorganism and host, has been extensively studied. AN chewing might disrupt the oral and intestinal microbiota communities through direct connect with the microbes it contains, altering PH, oxygen of oral and intestinal microenvironment, and disturbing the immune homeostasis. These mechanisms provide insights into the interplay between areca nut and host microbiota. Emerging studies have proposed that bidirectional interaction between polyphenols and intestinal microbes might play a potential role in the divergence of polyphenol, extracted from AN, among individuals with or without AN-induced cancer development and progression. Although some AN chewers have been aware of the harmful effects brought by AN, they cannot abolish this habit because of the addiction of AN. Increasing studies have tried to revealed that gut microbiota might influence the onset/development of addictive behaviors. Altogether, this review summarizes the possible reasons for the disturbance of host microbiota caused by areca nut chewing and clarifies the complex interaction between human microbiome and major constituents and the addiction and carcinogenicity of AN, tempting to provide novel insights into the development and utilization of it, and to control the adverse consequences caused by AN chewing.

Decoding the link associated with areca nut chewing and cardiovascular disease using hsCRP as a biomarker

Background

Chewing of areca nut is associated with various oral and systemic ill effects. The deleterious oral effects of areca nut have been widely documented to range from reactive lesions, periodontal health compromise to oral pre-cancer and cancerous states and have been described widely in the literature. The reported systemic effects of areca nut chewing are relatively less documented but reported in literature. Areca nut chewing may predispose to cardiovascular disease due to a systemic inflammatory response from the elevated levels of circulating inflammatory mediators. High-sensitivity C-reactive protein (hsCRP) is a systemic inflammatory biomarker to assess the risk of cardiovascular disease.

Materials and Methods

This cross-sectional, observational study was conducted among areca nut chewers (n = 50) and non-chewers (n = 50). Areca nut chewers were considered as chewers/cases. Blood samples were collected from the participants and hsCRP levels were studied. The data were analysed using SPSS software, version 21 for statistical significance. Chi-square test was used to compare categorical variables. Mann-Whitney U test was done to analyse continuous variables. The level of statistical significance was set at P value < 0.05.

Results

hsCRP mean was higher among the chewers (2.3 ± 3.7) compared to non-chewers (0.9 ± 1.3). The difference in hsCRP levels between the study group was statistically significant (P = 0.002).

Conclusion

This study demonstrates the link between areca nut and cardiovascular disease using hsCRP as biomarker.

Arecoline induces cardiotoxicity by upregulating and activating cardiac hypertrophy-related pathways in Sprague-Dawley rats

Habitual chewing of the areca nut increases the risk of mortality owing to cardiovascular disease, but few reports have revealed the cardiotoxicity mechanism of the areca nut. Arecoline has been reported to be the primary toxic constituent in the areca nut. In order to study the acute cardiotoxicity of the areca nut in the development of pathologic heart hypertrophy, we induced heart injury in rats using arecoline. Arecoline at a low dosage (5 mg/kg/day) or a high dosage (50 mg/kg/day) was intraperitoneally injected to Sprague-Dawley rats for 21 days. The change of heart function and biochemical pathways were investigated with echocardiography and Western blot. The results were presented that heart functions were weakened by arecoline stimulation, and western blotting analysis revealed an elevation in BNP levels in the heart after arecoline exposure. Arecoline induced IL-6-mediated activation of the MEK5/ERK5 and JAK2/STAT3 pathways, as well as mitogen-activated protein kinase signaling cascades. Further, arecoline increased the calcineurin and NFATc3 levels in the heart. In summary, our results suggest that arecoline causes significantly cardiotoxicity and heart damage by inducing several hypertrophy-related signaling pathways, including IL-6-induced MEK5/ERK5, JAK2/STAT3, mitogen-activated protein kinases, and calcineurin signaling pathways. The study elucidated, for the first time, the possible cardiac hypertrophy mechanisms underlying the cardiotoxicity of the areca nut.

A comparison for the effects of raw, smoked, and smoked and brined areca nut extracts on the immune and inflammatory responses in the Kunming mice

Chewing of areca nuts is quite popular in various regions worldwide. Previous studies have demonstrated the pharmacological and toxicological effects of fresh areca nuts. However, processed areca nuts, which are popular in the Hunan province of China, have not been extensively studied for its biological effect. This study aimed at investigating the impact of the acrea nut extracts (ANE) prepared from the raw material, the semi-product, and the final product on the immune system and inflammation-related markers in the Kunming mice. The mice were assigned to seven different groups and administered different ANE at two concentrations (1X and 5X) for four weeks. Total body weight gain and organ coefficient of the liver, spleen, and kidney, as well as the immune system and inflammation-related markers were evaluated. The results revealed that processed areca nuts have a much milder effect on the mice immune system and some inflammatory markers than fresh areca nut in the Kunming mice. PRACTICAL APPLICATIONS: Chewing various forms of areca nuts is popular in China, Southeast Asia, and other regions. People from Hunan, China prefer to chew a processed areca nut, which has rarely been studied. This manuscript explores the effects of three kinds of areca nut extracts on the immune system- and inflammation-related indicators in Kunming mice. The obtained results revealed that processed areca nuts had significantly milder effects than the raw nut/nut extract, particularly on the body weight, immune responses, and inflammatory markers. The results of the present study provide some new directions for the areca nut industry and raise public awareness for the undesirable effects of areca nuts.

Association of betel nut chewing with exercise performance in a military male cohort: the CHIEF study

INTRODUCTION

Betel nut chewing may cause obesity, neurohormonal activation and inflammation, possibly impairing exercise performances.

METHODS

We examined the cross-sectional association in 4388 military male adults aged 18-50 years from the cardiorespiratory fitness in armed forces study in Taiwan between 2013 and 2014. The status of betel nut chewing was classified as current and former/never based on each participant's response to a questionnaire. Physical fitness was evaluated by three basic exercise tests including 3000 m running, 2 min sit-ups and 2 min push-ups. Multiple logistic regression for the best 10% and the worst 10% performers in each exercise, and linear regression were used to determine the relationship.

RESULTS

There were 564 current chewers and 3824 non-current chewers for the analysis. The linear regression shows that current betel nut chewing was positively correlated with 3000 m running duration (r=0.37, p=0.042) after adjusting for age, service specialty, body mass index, exercise frequency and alcohol intake. In addition, the logistic regression shows that as compared with non-current chewers, current chewers had lower odds of being the top 10% performers in 2 min push-ups and higher odds of being the bottom 10% performers in 2 min sit-ups (ORs and 95% CIs: 0.71 (0.50 to 0.99) and 1.32 (1.00 to 1.75), respectively). However, the associations between betel nut chewing and physical fitness were all insignificant after further adjusting for current smoking.

CONCLUSIONS

Our findings suggest that the impairment of physical fitness associated with betel nut chewing of military young men might be mainly mediated or moderated by the coexisted cigarette smoking.

Betel nut chewing and the risk of chronic kidney disease: evidence from a meta-analysis

PURPOSE

To investigate and quantify the potential association between betel nut chewing and the risk of chronic kidney disease (CKD).

METHODS

We searched five online databases including PubMed, EMBASE, ISI Web of Science, Wanfang and CNKI to identify observational studies that published prior to May, 1, 2017. The primary outcome was the association between betel nut chewing and CKD expressed as odds ratio (OR) and the corresponding 95% confidence interval (95%CI) after adjustment for other covariates. Meta-analysis was performed using RevMan 5.3 software; the leave-one-out sensitivity analysis was used to confirm the stability of drawn conclusion.

RESULTS

Five studies comprising a total of 10,562 CKD patients and 34,038 subjects without CKD that analyzed the relationship between betel nut chewing and CKD were included in our study; all the included studies were performed in Taiwan. After the adjustment for covariates, the combined adjusted ORs showed that betel nut used had 1.44 times higher risk to develop CKD compared with non-chewers (OR 1.44, 95%CI 1.08-1.92).

CONCLUSIONS

Betel nut chewing could significantly increase the risk of CKD, indicating that betel nut chewing may exist as an independent risk factor for CKD. Further investigation should be warranted.

Betel nut chewing associated with increased risk of arterial stiffness

BACKGROUND

Betel nut chewing is associated with certain cardiovascular outcomes. Subclinical atherosclerosis may be one link between betel nut chewing and cardiovascular risk. Few studies have examined the association between chewing betel nut and arterial stiffness. The aim of this study was thus to determine the relationship between betel nut chewing and arterial stiffness in a Taiwanese population.

METHODS

We enrolled 7540 eligible subjects in National Cheng Kung University Hospital from October 2006 to August 2009. The exclusion criteria included history of cerebrovascular events, coronary artery disease, and taking lipid-lowering drugs, antihypertensives, and hypoglycemic agents. Increased arterial stiffness was defined as brachial-ankle pulse wave velocity (baPWV) ≥1400cm/s. According to their habit of betel nut use, the subjects were categorized into non-, ex-, and current chewers.

RESULTS

The prevalence of increased arterial stiffness was 32.7, 43.3, and 43.2% in non-, ex- and current chewers, respectively (p=0.011). Multiple logistic regression analysis revealed that ex-chewers (odds ratio [OR] 1.69, 95% confidence interval (CI)=1.08-2.65) and current chewers (OR 2.29, 95% CI=1.05-4.99) had elevated risks of increased arterial stiffness after adjustment for co-variables.

CONCLUSIONS

Both ex- and current betel nut chewing were associated with a higher risk of increased arterial stiffness. Stopping betel nut chewing may thus potentially be beneficial to reduce cardiovascular risk, based on the principals of preventive medicine.

Arecoline Induces Neurotoxicity to PC12 Cells: Involvement in ER Stress and Disturbance of Endogenous H2S Generation

Arecoline is a major alkaloid of areca nut and has been effect on central nervous system. Although arecoline-induced neurotoxicity has been reported, the possible underlying neurotoxic mechanisms have not yet been elucidated. Increasing evidences have shown that both excessive endoplasmic reticulum (ER) stress and disturbance of hydrogen sulfide (H2S) production are involved in the pathophysiology of numerous neurodegenerative diseases. Here, the purpose of present study was to verify whether ER stress and the disturbance of endogenous H2S generation are also involved in arecoline-caused neurotoxicity. We found that treatment of PC12 cells with arecoline induced the down-regulation of cells viability and up-regulation of apoptosis and the activity of caspase-3, indicating the neurotoxic role of arecoline to PC12 cells. In addition, arecoline also increased the expression of Bax (pro-apoptotic protein) and attenuated the expression of Bcl-2 (anti-apoptotic protein) in PC12 cells. Simultaneously, arecoline caused excessive ER stress in PC12 cells, as evidenced by the up-regulations of Glucose-regulated protein 78 (GRP78), CCAAT/enhancer binding protein homologous protein (CHOP), and Cleaved caspase-12 expressions. Notably, the level of H2S in the culture supernatant and the expressions of cystathionine β-synthase and 3-mercaptopyruvate sulfurtransferase (two major enzymes for endogenous H2S generation in PC12 cells) were also reduced by arecoline treatment. These results indicate that arecoline-caused neurotoxicity to PC12 cells is involved in ER stress and disturbance of endogenous H2S generation and suggest that the modulation of ER stress and endogenous H2S generation may be potential therapeutic approach in treatment of arecoline-caused neurotoxicity.

Areca Nut Chewing Complicated with Non-Obstructive and Obstructive ST Elevation Myocardial Infarction

Areca nut chewing is one of the most prevalent substance abuse habits in the world, and it is associated with the risk of a variety of medical challenges including hypertension, arrhythmia, and coronary artery disease (CAD). However, ST elevation myocardial infarction (STEMI) is an extremely rare complication of areca nut chewing. Herein we report two cases where patients suffered from STEMI after areca nut chewing. The first case involved a patient with non-obstructive CAD and non-sustained ventricular tachycardia during hospitalization. The second case revealed left circumflex artery total occlusion, and primary percutaneous coronary intervention was performed. Initially, the levels of arecoline and arecaidine plasma were checked in these two cases after admission. Although both cases revealed increased levels, the second case showed substantially higher values than the first case. In general, these two cases remind physicians that areca nut chewing may cause myocardial injury with different severity, although STEMI with true coronary obstruction remains an extremely rare but possible complication after areca nut chewing.

KEY WORDS

Areca nut chewing; Coronary obstruction; ST elevation myocardial infarction.

Oral submucous fibrosis: an update

Oral submucous fibrosis (OSF) is a premalignant condition caused by betel chewing. It is very common in Southeast Asia but has started to spread to Europe and North America. OSF can lead to squamous cell carcinoma, a risk that is further increased by concomitant tobacco consumption. OSF is a diagnosis based on clinical symptoms and confirmation by histopathology. Hypovascularity leading to blanching of the oral mucosa, staining of teeth and gingiva, and trismus are major symptoms. Major constituents of betel quid are arecoline from betel nuts and copper, which are responsible for fibroblast dysfunction and fibrosis. A variety of extracellular and intracellular signaling pathways might be involved. Treatment of OSF is difficult, as not many large, randomized controlled trials have been conducted. The principal actions of drug therapy include antifibrotic, anti-inflammatory, and antioxygen radical mechanisms. Potential new drugs are on the horizon. Surgery may be necessary in advanced cases of trismus. Prevention is most important, as no healing can be achieved with available treatments.

A review of the systemic adverse effects of areca nut or betel nut

Areca nut is widely consumed by all ages groups in many parts of the world, especially south-east Asia. The objective of this review is to systematically review and collate all the published data that are related to the systemic effects of areca nut. The literature search was performed by an electronic search of the Pubmed and Cochrane databases using keywords and included articles published till October 2012. We selected studies that covered the effect of areca nut on metabolism, and a total of 62 studies met the criteria. There is substantial evidence for carcinogenicity of areca nut in cancers of the mouth and esophagus. Areca nut affects almost all organs of the human body, including the brain, heart, lungs, gastrointestinal tract and reproductive organs. It causes or aggravates pre-existing conditions such as neuronal injury, myocardial infarction, cardiac arrhythmias, hepatotoxicity, asthma, central obesity, type II diabetes, hyperlipidemia, metabolic syndrome, etc. Areca nut affects the endocrine system, leading to hypothyroidism, prostate hyperplasia and infertility. It affects the immune system leading to suppression of T-cell activity and decreased release of cytokines. It has harmful effects on the fetus when used during pregnancy. Thus, areca nut is not a harmless substance as often perceived and proclaimed by the manufacturers of areca nut products such as Pan Masala, Supari Mix, Betel quid, etc. There is an urgent need to recognize areca nut as a harmful food substance by the policy makers and prohibit its glamorization as a mouth freshener. Strict laws are necessary to regulate the production of commercial preparations of areca nut.

Stimulation of non-neuronal muscarinic receptors enhances chemerin/ChemR23 system in dysfunctional endothelial cells

AIMS

Endothelial cells play a pivotal role in vascular intimal inflammation during cardiovascular diseases. The chemerin/ChemR23 system in endothelial cells is one of physiological mechanisms that regulate inflammatory responses. Our previous studies indicated that stimulation of non-neuronal muscarinic receptor (NNMR) improved endothelial dysfunction. However, the relationship between the chemerin/ChemR23 signaling axis and NNMR in endothelial cell is poorly understood. Here, we first investigated whether the modulation of chemerin/ChemR23 signaling axis is involved in NNMR-mediated endothelial protection.

MAIN METHODS

Cultured rat aortic endothelial cells (RAECs) were used. The ChemR23 protein expression and chemerin secretion were measured using Western blot analysis. The gene expression level of ChemR23 was examined with reverse transcriptase PCR (RT-PCR). The production of nitric oxide (NO) was determined by a nitrate reductase assay kit.

KEY FINDINGS

A sharp decline of chemerin secretion and ChemR23 protein/gene expression was observed in RAECs after exposed to homocysteine at concentration of 0.5 mmol/L. Arecoline (10 μmol/L) pretreatment increased ChemR23 protein expression as well as mRNA expression, and enhanced the secretion of chemerin. Arecoline could also reverse the decreased ChemR23 mRNA expression induced by uric acid, high glucose, or oxidized low-density lipoprotein. Furthermore, the modulation of arecoline on chemerin/ChemR23 signaling axis was absolutely abolished in the presence of the nonselective muscarinic receptors antagonist atropine 1 μmol/L. Additionally, arecoline improved endothelial dysfunction by increasing the reduced NO production induced by uric acid, which was blocked by anti-ChemR23 antibody.

SIGNIFICANCE

The chemerin/ChemR23 signaling axis participates in NNMR-mediated protection against endothelial dysfunction in cardiovascular system.