Sympathetic response to betel chewing

Virtual screenings of the bioactive constituents of tea, prickly chaff, catechu, lemon, black pepper, and synthetic compounds with the main protease (Mpro) and human angiotensin-converting enzyme 2 (ACE 2) of SARS-CoV-2

Background

COVID-19 has mutation capability, and there are no specific drug therapies that are available to fight or inhibit the proteins of this virus. The present study aims to investigate the binding affinity of the bioactive and synthetic compounds with the main protease (Mpro) enzymes and angiotensin-converting enzyme 2 (ACE 2) by computational approach. PASS prediction, pharmacokinetics, and toxicological properties prediction studies were performed through the Google PASS prediction and Swiss ADME/T website. Besides, molecular docking studies were accomplished by BIOVIA Discovery Studio 2020, UCSF Chimera, and PyRx autodock vina.

Results

The docking scores were inferred and the selected compounds showed results varying from −3.2 to −9.8 (kcal/mol). Theaflavin scored the highest docking score to the 5REB, 6VW1, and 1R42 enzymes and showed the binding affinity as −6.3 kcal/mol, −9.8 kcal/mol, and −8.6 kcal/mol, respectively. Again, kaempferol showed the best binding affinity to the 7BQY (−7.1 kcal/mol) and 6Y2FB (−6.6 kcal/mol) enzymes. All the chemical constituents showed better probability in action in pass prediction analysis. Besides, no ligands (except theaflavin) have any conflict with Lipinski’s rules of five, which authorized the drug probability of these ligands.

Conclusion

Therefore, the selected compounds could be considered a potential herbal treatment source against SARS-CoV-2.

Determining High Prevalence of Betel-Quid Chewing and Cigarette Smoking by Occupation Using the Taiwan National Health Interview Survey

Background: Effectiveness of oral cancer screening depends on identifying high-risk groups. People with betel quid chewing or cigarette smoking habits are often reluctant to attend screenings. Given that use of both substances is associated with certain occupations, a targeted approach should be applied to improve the effectiveness of screening programs. Objectives: This study sought to identify occupations with a high prevalence of betel quid chewing and cigarette smoking and to investigate their changing trends using the Taiwan National Health Interview Survey (NHIS) database. Methods: The NHIS database for 2009 and 2013 were used. We estimated prevalence of current betel quid and/or cigarette use among those aged 20-64 years old. Occupations were classified using the International Standard Classification of Occupations (ISCO-88). Statistical analyses included indirect standardized rates and cluster analysis of chewing/smoking habits. Results: Drivers, mobile-plant operators, and extraction and building trades workers had the highest prevalence of betel quid chewing and cigarette smoking (chewing: 30.92% and 29.62%; smoking: 61.16% and 62.22%). Many occupations had large indirect standardized rates for chewing but not smoking. Both habits are associated with each other (r = 0.81, p < 0.001). Use appeared to decrease based on comparison between 2009 and 2013. Conclusions: Drivers and construction laborers showed high prevalence of betel chewing and cigarette smoking. The chewing habit is actually more prevalent in several sub-occupations. The survey results also revealed lower attendance by construction laborers at oral cancer screenings. Oral cancer screening and awareness should be emphasized in the identified occupations.

Factors affecting commencement and cessation of betel quid chewing behaviour in Malaysian adults

Background

Betel quid chewing is a common habit widely practiced in Southern Asian populations. However, variations are seen in the content of a betel quid across the different countries. Factors associated with commencement and cessation of this habit has been numerously studied. Unfortunately, data on Malaysian population is non-existent. This study aims to determine the factors associated with the inception and also cessation of betel quid chewing behaviour among Malaysian adults.

Method

This study is part of a nationwide survey on oral mucosal lesions carried out among 11,697 adults in all fourteen states in Malaysia. The questionnaire included sociodemographic information and details on betel quid chewing habit such as duration, type and frequency. The Kaplan-Meier estimates were calculated and plotted to compare the rates for the commencement and cessation of betel quid chewing behaviour. Cox proportional hazard regression models were used to calculate the hazard rate ratios for factors related to commencement or cessation of this habit.

Results

Of the total subjects, 8.2% were found to be betel quid chewers. This habit was more prevalent among females and, in terms of ethnicity, among the Indians and the Indigenous people of Sabah and Sarawak. Cessation of this habit was more commonly seen among males and the Chinese. Females were found to be significantly more likely to start (p < 0.0001) and less likely to stop the quid chewing habit. Females, those over 40 years old, Indians and a history of smoking was found to significantly increase the likelihood of developing a quid chewing habit (p < 0.0001). However, those who had stopped smoking were found to be significantly more likely to promote stopping the habit (p = 0.0064). Cessation was also more likely to be seen among those who chewed less than 5 quids per day (p < 0.05) and less likely to be seen among those who included areca nut and tobacco in their quid (p < 0.0001).

Conclusion

Factors that influence the development and cessation of this behaviour are gender, age, ethnicity, and also history of smoking habit while frequency and type of quid chewed are important factors for cessation of this habit.

Betel nut chewing and subclinical ischemic heart disease in diabetic patients

Background. This study investigated the association between betel nut chewing and subclinical ischemic heart disease (IHD) in Taiwanese type 2 diabetic patients. Methods. A total of 394 male patients aging ≥45 years and without previous heart disease were studied. Among them 349 had no habit of chewing betel nut and 45 possessed the habit for ≥5 years. Subclinical IHD was diagnosed by a Minnesota-coded resting electrocardiogram and was present in 71 cases. Statistical analyses were performed considering confounding effects of age, diabetic duration, smoking, body mass index, blood pressure, dyslipidemia, and metabolic control status. Results. Betel nut chewers were younger and had higher prevalence of smoking (86.7% versus 60.5%), higher body mass index, poorer glycemic control, and higher prevalence of subclinical IHD (28.9% versus 16.6%). Patients with subclinical IHD were older and had higher prevalence of betel nut chewing (18.0% versus 9.9%). The multivariate-adjusted odds ratio for subclinical IHD for chewers versus nonchewers was 4.640 (1.958–10.999). The adjusted odds ratios in younger or older patients divided by the median age of 63 years were similar: 4.724 (1.346–16.581) and 4.666 (1.278–17.028), respectively. Conclusions. Betel nut chewing is significantly associated with increased risk of subclinical IHD.

Areca nut dependence among chewers in a South Indian community who do not also use tobacco

AIMS

Previously reported research suggests a dependence syndrome for areca nut use, though well-designed studies are virtually non-existent. The goal of this study was to examine evidence of areca dependence in a sample of areca-only (i.e. no tobacco) chewers using modified measurement scales.

DESIGN

A purposive sample of chewers, identified via local informants and advertisements, was surveyed from January to March of 2005.

SETTING

Six villages in Dakshina Kannada District, Karnataka State, India.

PARTICIPANTS

Fifty-nine daily areca chewers who do not also currently use any form of tobacco.

MEASUREMENTS

Questionnaires included modified versions of the Fagerström Tolerance Questionnaire, Cigarette Dependence Scale (CDS-5) and the Smokeless Tobacco Dependence Scale (STDS). Additional questions assessed demographic characteristics and patterns of use.

FINDINGS

Approximately half of respondents reported 1-3 chews/day (mean = 1.9; SD = 0.98). The average number of chewing episodes/day was 4.4 (SD = 3.4) and the average number of nuts/day was 1.2 (SD = 1.1). Users' typical chew lasts up to 20 minutes and includes spitting out the juices and rinsing the mouth with water. Overall, the levels of reported dependence symptoms were quite low, but approximately 44% of chewers endorsed at least one of the following items: continued use despite illness or mouth wounds, difficulty refraining from chewing in forbidden places, or craving during periods of abstinence. Approximately 15.4% of chewers reported at least one intentional quit attempt and a subset had summary scores indicative of dependence (13.6% had scores >16 on the CDS-5 and 5.3% had scores >11 on the STDS). Dependence scores were positively correlated with frequency of chews/day.

CONCLUSIONS

The symptoms of dependence observed in a subset of areca-only chewers warrant further investigation. Next steps should include well-controlled laboratory evaluation of dependence features.

The transcript and metabolite networks affected by the two clades of Arabidopsis glucosinolate biosynthesis regulators

In this study, transcriptomics and metabolomics data were integrated in order to examine the regulation of glucosinolate (GS) biosynthesis in Arabidopsis (Arabidopsis thaliana) and its interface with pathways of primary metabolism. Our genetic material for analyses were transgenic plants overexpressing members of two clades of genes (ALTERED TRYPTOPHAN REGULATION1 [ATR1]-like and MYB28-like) that regulate the aliphatic and indole GS biosynthetic pathways (AGs and IGs, respectively). We show that activity of these regulators is not restricted to the metabolic space surrounding GS biosynthesis but is tightly linked to more distal metabolic networks of primary metabolism. This suggests that with similarity to the regulators we have investigated here, other factors controlling pathways of secondary metabolism might also control core pathways of central metabolism. The relatively broad view of transcripts and metabolites altered in transgenic plants overexpressing the different factors underlined novel links of GS metabolism to additional metabolic pathways, including those of jasmonic acid, folate, benzoic acid, and various phenylpropanoids. It also revealed transcriptional and metabolic hubs in the "distal" network of metabolic pathways supplying precursors to GS biosynthesis and that overexpression of the ATR1-like clade genes has a much broader effect on the metabolism of indolic compounds than described previously. While the reciprocal, negative cross talk between the methionine and tryptophan pathways that generate GSs in Arabidopsis has been suggested previously, we now show that it is not restricted to AGs and IGs but includes additional metabolites, such as the phytoalexin camalexin. Combining the profiling data of transgenic lines with gene expression correlation analysis allowed us to propose a model of how the balance in the metabolic network is maintained by the GS biosynthesis regulators. It appears that ATR1/MYB34 is an important mediator between the gene activities of the two clades. While it is very similar to the ATR1-like clade members in terms of downstream gene targets, its expression is highly correlated with that of the MYB28-like clade members. Finally, we used the unique transgenic plants obtained here to show that AGs are likely more potent deterrents of the whitefly Bemisia tabaci compared with IGs. The influence on insect behavior raises an important question for future investigation of the functional aspect of our initial finding, which pointed to enriched expression of the MYB28-like clade genes in the abaxial domain of the Arabidopsis leaf.

Effect of chewing a single betel-quid on autonomic nervous modulation in healthy young adults

Betel-quid is widely used around the world as a stimulant for the autonomic nervous system. The aim of this study was to assess the effect of betel-quid chewing on autonomic nervous modulation by using spectral heart rate variability (HRV) analysis. Twenty healthy young adults were included in this study. Each subject chewed a single betel-quid containing one betel nut or a piece of chewing-gum for 60 min on different days in random order. Spectral HRV measures were obtained before, and 5, 30 and 60 min after starting to chew betel-quid or gum. Sequential changes in HRV measures were compared between chewing gum and betel-quid. Heart rate was significantly elevated after 5 min chewing betel-quid, but not after chewing gum. The normalized low-frequency power and low-/high-frequency power ratio were elevated after 5 min chewing gum or betel-quid; however, the normalized high-frequency power was reduced after 5 min chewing gum or betel-quid. The percentage changes in total power after 5, 30 and 60 min chewing betel-quid were significantly lower than those after chewing gum. This study confirms that novice chewing of betel-quid modulates autonomic nervous system activity; transiently enhancing sympathetic activity and gradually suppressing vagal activity in healthy young adults.

Betel nut chewing is associated with hypertension in Taiwanese type 2 diabetic patients

Betel nut chewing is associated with oral cancers and diabetes. This study investigated whether betel nut chewing could be associated with hypertension in Taiwanese patients with type 2 diabetes mellitus (T2DM). The data of a total of 81,226 (37,226 men and 44,000 women) patients with T2DM obtained from a cross-sectional telephone survey in a national sample of diabetic patients in Taiwan were analyzed. Hypertension was defined by a positive history or reported systolic blood pressure>or=140 mmHg and/or diastolic blood pressure>or=90 mmHg. Analyses were performed in separate sexes with consideration paid to the potential confounding effects of age, diabetic duration, body mass index and smoking. The prevalences of betel nut chewing in men and women were 20.4% and 1.1%, respectively. Betel nut chewing was more common in the younger age groups of the male sex. The multivariate-adjusted odds ratios for hypertension in chewers vs. non-chewers were 1.067 (1.007-1.131) and 1.897 (1.534-2.346) for men and women, respectively. In multiple linear regression, although no adjustment was made for the use of antihypertensive agents, betel nut chewing was significantly associated with blood pressure, with regression coefficients of 0.958+/-0.163 (SEM) for systolic and 0.441+/-0.108 for diastolic blood pressure in men; and the respective values for women were 1.805+/-0.618 and 1.198+/-0.393. In conclusion, betel nut chewing was significantly associated with hypertension in Taiwanese patients with T2DM and the association was stronger in women.

Comparing factors affecting commencement and cessation of betel quid chewing behavior in Taiwanese adults

BACKGROUND

Betel quid is the fourth most common used substance in the world after tobacco, alcohol and caffeine. Although factors related to betel quid chewing or cessation of behaviors were reported previously, few studies simultaneously compared both behaviors in the same population. In addition, it is essential to consider time-to-event concept, since the chance of developing or stopping habit may vary over time. The purpose of this study was to compare the risk factors for commencement and cessation of betel quid chewing behaviors in a time-to-event setting.

METHODS

A stratified multi-stage cluster sampling with selection probabilities proportional to size (PPS) was designed for Taiwanese adults with aged 18 years old and above. Kaplan-Meier estimates and Cox proportional hazard regression models were used to compare and calculate the hazard rate ratios for related factors to commencement or cessation of chewing habits.

RESULTS

In Taiwan, men had a higher betel quid chewing rate (M: 20.9%, W: 1.2%), but woman chewers had a lower cessation rate (M: 27.5%, W: 12.7%). The hazard rate ratio (HRR) of having chewing habit changed from 4.22 (men vs women) univariately to 1.38 multivariablely, which indicated gender differences were confounded by other factors. In multivariable analysis, the risk factors of gender, education and ethnicity were significantly associated with both starting and cessation of betel quid chewing behavior. The factors of occupation, cigarette smoking and alcohol drinking were only associated with starting habit.

CONCLUSION

Commencement or cessation of chewing behavior involves a scenario of time, hence it is preferable to use a time-to-event approach for the comparison. The cessation rates of betel quid chewing were decreasingly associated with the daily consumption of betel quid. Hence, reducing of daily amount in betel quid cessation program may be associated with future stopping habit.

Factors associated with quitting areca (betel) quid chewing

OBJECTIVES

The purpose of this study was to provide useful data for a future abstinence project by identifying the factors related to quitting areca (betel) quid chewing.

METHODS

The study was cross-sectional. Data on demographic variables, psychological factors and substance-use behaviors were collected via questionnaires from 326 participants.

RESULTS

Multiple logistic regression analysis indicated that the areca/betel quid chewers who were less educated (OR = 0.58, 95% CI = 0.34-0.98) were least likely to try to give up. Among the chewers who tried to quit, those employed as full-time drivers (OR = 2.24, 95% CI = 1.14-4.39), who had drinking habits (OR = 2.41, 95% CI = 1.24-4.66), and who preferred to chew only betel quid wrapped with leaf (OR = 4.44, 95% CI = 1.99-9.90) were more likely to fail. Chewers who successfully quit had a higher internal health locus of control compared with those who failed to quit (one-point increments, OR = 0.94, 95% CI = 0.90-0.98).

CONCLUSIONS

The results suggest that health educators and researchers can better influence people's chewing behavior if the importance of chewers' education level, job type, substance use (i.e. drinking habits, type of betel quid), and level of health locus of control are all taken into consideration when devising interventions.

Suppressive effects of dichloromethane fraction from the Areca catechu nut on naloxone-precipitated morphine withdrawal in mice

In the present study, we investigated the effect of the dichloromethane fraction from Areca catechu nut on the severity of naloxone-precipitated morphine withdrawal in morphine-dependent mice. A single intraperitoneal injection of dichloromethane fraction at dose of 125 and 175 mg/kg significantly delayed the onset of withdrawal jumping behavior in a concentration-dependent manner compared to that of saline controls. The dichloromethane fractions also significantly decreased jumping numbers and faecal and urinary excretions during the withdrawal period.

Uncovering the relation between betel quid chewing and cigarette smoking in Taiwan

OBJECTIVE

To describe the characteristics of betel quid chewers and to investigate the behavioural and mortality relations between betel quid chewing and cigarette smoking.

METHOD

Prevalence and mortality risks of betel quid chewers by smoking status were calculated, based on the National Health Interview Survey in 2001 and a community based cohort, respectively. Cox's proportional hazards model was used to adjust mortality risks for age, alcohol use, and education.

RESULTS

Almost all betel quid chewers were smokers, and most started chewing after smoking. Chewers were predominantly male, mostly in their 30s and 40s, more likely being among the lowest educational or income group, and residing in the eastern regions of Taiwan. On average, betel quid chewers who smoked consumed 18 pieces of betel quid a day, and smoked more cigarettes per day. Far more smokers use betel quid than non-smokers (27.5% v 2.5%), but ex-smokers quit betel quid more than smokers (15.1% v 6.8%). The significantly increased mortality of betel quid users who also smoked, for all causes, all cancer, oral cancer, and cancer of the nasopharynx, lung, and liver, was the result of the combined effects of chewing and smoking. Smokers who chewed betel quid nearly tripled their oral cancer risks from a relative risk of 2.1 to 5.9. Increasing the number of cigarettes smoked among betel quid chewers was associated with a synergistic effect, reflective of the significant interaction between the two.

CONCLUSION

To a large extent, the serious health consequences suffered by betel quid chewers were the result of the combined effects of smoking and chewing. Betel quid chewing should not be considered as an isolated issue, but should be viewed conjointly with cigarette smoking. Reducing cigarette smoking serves as an important first step in reducing betel quid chewing, and incorporating betel quid control into tobacco control may provide a new paradigm to attenuate the explosive increase in betel quid use in Taiwan.

Effects of aqueous extracts of "Betel quid" and its constituents on testosterone production by dispersed mouse interstitial cells

Betel quid (BQ) is a favorite chewing item among many communities in different parts of Asia where it is popular by different names. BQ is a unique combination of nut or fruit from the Areca catechu Linn. (AN) tree, leaf from the Piper betle Linn. (BL) vine, slaked lime, paste of bark from the Acacia catechu tree and other spices. AN has been used successfully in various traditional medicines by different civilizations over several ages. Initially condemned by the medical communities for its health hazards, identification and application of potent pharmacologically bioactive compounds from different constituents of BQ have rekindled growing interest in related investigations. Curious about the stimulating role of BQ, we investigated the potential steroidogenic activity of hot water extract from BQ and its constituents and arecoline on testosterone producing ability in an in vitro experiment. Enzyme dissociated interstitial cells from adult mouse testes (ICR strain) were cultured with/without different doses of the extracts and the level of testosterone produced was assayed by an enzyme immunoassay (EIA) technique. It was found that at lower doses of arecoline, AN and BL extracts had significantly stimulated testosterone production over the basal level (p < 0.05). BQ extract, on the other hand, did not show any significant effect on testosterone production. Combinations of arecoline at low doses with 10 ng/ml ovine leutinizing hormone (oLH) showed increases in testosterone produced, while cyclic adenosine monophosphate (cAMP) co-culture showed dose-related inhibition. Our current finding hints at the possible dose-dependent dualistic role of AN and BL extracts and arecoline for testosterone production employing possible non-cAMP-dependent pathway of steroidogenesis. However, the identity of the active compounds besides arecoline and the exact mechanism involved remains to be further investigated.

Areca quid chewing and methamphetamine use in Taiwanese adolescents

The association between areca quid chewing and methamphetamine (MAMP) use in Taiwanese adolescents was examined in 200 MAMP users and 400 non-users. Subjects were interviewed individually regarding the experience of chewing areca quid and the evidence of lifetime areca quid use disorder. The ages at which they initially chewed areca quid and used MAMP were also evaluated. The results revealed that areca quid chewing and areca quid use disorders were more common in both male and female MAMP users than in non-users. Among those who chewed areca quid and used MAMP, the mean age at initial MAMP use was older than the mean age at initial chewing of areca quid in males but not in females. MAMP users who chewed areca quid were subdivided into three groups according to the sequence of initial MAMP use and chewing areca quid. Although most males and females started chewing areca quid before using MAMP, this pattern was more prevalent in males. Adolescent MAMP users need to be educated about deleterious health sequelae caused by chewing areca quid. Adolescent areca quid chewers need to be monitored for possible progression to MAMP use.

Cerebral hemodynamic responses to betel chewing: a Doppler study

We sought to evaluate cerebral hemodynamic responses to betel chewing. Thirty healthy male volunteers (mean age = 35 years), ten new chewers, ten occasional chewers, and ten chronic chewers were included in this study. We used carotid duplex sonography and transcranial Doppler to measure the flow velocities and flow volume (FV) of the common carotid (CCA), internal carotid (ICA), external carotid (ECA) arteries, and the flow velocity of middle cerebral artery (MCA). Blood pressure (BP) and heart rate (HR) were recorded simultaneously. All subjects were asked to chew fruit-flavored chewing gum for 10 minutes. Blood flows of the above vessels were measured four times at baseline and at the 2nd, 6th, and 12th minute after chewing. A repeated study was followed in the same subject but substituted with betel nut. Chronic chewers had delayed onset time and shortened vanishing time of facial-flushing sensation. Systolic and diastolic BPs were mildly elevated during gum chewing (p = 0.008 and 0.015, respectively), whereas diastolic BP was dropped during betel chewing (p = 0.008). Heart rate increased prominently during betel chewing (p < 0.0001), especially in new and occasional chewers. The peak systolic, end diastolic velocities, and FV in ECA and CCA increased significantly during betel chewing (p < 0.0001). The blood flows in the ICA and MCA had no significant changes during gum or betel chewing. Betel chewing has a central sympathetic effect resulting in accelerated HR, increased blood flows in ECA and CCA, but has a peripheral cholinergic effect resulting in a drop of diastolic BP. Intracranial cerebral hemodynamics is not affected during betel chewing. The inotropic and chronotropic effect to the heart from betel chewing is probably an unfavorable risk for patients with ischemic heart disease.

Areca nut-abuse liability, dependence and public health

To define a dependence syndrome may convey attention upon a public health problems hitherto relatively ignored. It may, however, stigmatize substance use, especially when western diagnostic criteria are applied to essentially culture-bound substances. However, when the pattern of use of a substance results in significant personal harm, then whether dependence exists or not is less important than developing an appropriate response, if its use is associated with significant morbidity and mortality. Such is the case with areca nut, the fourth most commonly used drug in the world after tobacco, alcohol and caffeine. In this paper I will explore its use and properties with respect to its abuse and dependence liability and consider the associated implications for public health.

Neurological aspects of areca and betel chewing

Betel quid chewing has been claimed to produce a sense of well-being, euphoria, warm sensation of the body, sweating, salivation, palpitation, heightened alertness and increased capacity to work. These effects suggest that betel quid chewing affects predominantly the central and autonomic nervous systems. Several studies have been conducted to elucidate the central and autonomic effects of betel quid chewing. The results are: (1) betel quid chewing increased the heart rate with onset within 2 minutes, maximal effect within 4-6 minutes and an average duration of 16.8 minutes. The cardio-acceleratory response was more prominent for fresh and occasional chewers than for habitual chewers; (2) betel quid chewing increased the skin temperature with onset and duration similar to a cardio-acceleratory response. The hyperthermic effect was abolished by atropine and partly inhibited by propranolol. (3) Betel quid chewing had no effect on simple reaction time but shortened the choice reaction time. (4) Betel quid chewing produced widespread cortical desynchronization of EEG. (5) Chewing of one or two betel quids attenuated the sympathetic skin response while continued consumption of more than two betel quids affected the RR interval variation. (6) Plasma concentrations of noradrenaline and adrenaline were elevated during betel quid chewing. These studies have confirmed several effects claimed by betel quid users. The effects of betel quid chewing appeared to be habit-related and dose-dependent. Although arecoline has been thought to be responsible for several effects of betel quid chewing, the present data suggest a role also played by sympathetic activation.

Effects of Betel chewing on the central and autonomic nervous systems

Betel chewing has been claimed to produce a sense of well-being, euphoria, heightened alertness, sweating, salivation, a hot sensation in the body and increased capacity to work. Betel chewing also leads to habituation, addiction and withdrawal. However, the mechanisms underlying these effects remain poorly understood. Arecoline, the major alkaloid of Areca nut, has been extensively studied, and several effects of betel chewing are thought to be related to the actions of this parasympathomimetic constituent. However, betel chewing may produce complex reactions and interactions. In the presence of lime, arecoline and guvacoline in Areca nut are hydrolyzed into arecaidine and guvacine, respectively, which are strong inhibitors of GABA uptake. Piper betle flower or leaf contains aromatic phenolic compounds which have been found to stimulate the release of catecholamines in vitro. Thus, betel chewing may affect parasympathetic, GABAnergic and sympathetic functions. Betel chewing produces an increase in heart rate, blood pressure, sweating and body temperature. In addition, EEG shows widespread cortical desynchronization indicating a state of arousal. In autonomic function tests, both the sympathetic skin response and RR interval variation are affected. Betel chewing also increases plasma concentrations of norepinephrine and epinephrine. These results suggest that betel chewing mainly affects the central and autonomic nervous systems. Future studies should investigate both the acute and chronic effects of betel chewing. Such studies may further elucidate the psychoactive mechanisms responsible for the undiminished popularity of betel chewing since antiquity.

Effects of Betel chewing on the central and autonomic nervous systems

Betel chewing has been claimed to produce a sense of well-being, euphoria, heightened alertness, sweating, salivation, a hot sensation in the body and increased capacity to work. Betel chewing also leads to habituation, addiction and withdrawal. However, the mechanisms underlying these effects remain poorly understood. Arecoline, the major alkaloid of Areca nut, has been extensively studied, and several effects of betel chewing are thought to be related to the actions of this parasympathomimetic constituent. However, betel chewing may produce complex reactions and interactions. In the presence of lime, arecoline and guvacoline in Areca nut are hydrolyzed into arecaidine and guvacine, respectively, which are strong inhibitors of GABA uptake. Piper betle flower or leaf contains aromatic phenolic compounds which have been found to stimulate the release of catecholamines in vitro. Thus, betel chewing may affect parasympathetic, GABAnergic and sympathetic functions. Betel chewing produces an increase in heart rate, blood pressure, sweating and body temperature. In addition, EEG shows widespread cortical desynchronization indicating a state of arousal. In autonomic function tests, both the sympathetic skin response and RR interval variation are affected. Betel chewing also increases plasma concentrations of norepinephrine and epinephrine. These results suggest that betel chewing mainly affects the central and autonomic nervous systems. Future studies should investigate both the acute and chronic effects of betel chewing. Such studies may further elucidate the psychoactive mechanisms responsible for the undiminished popularity of betel chewing since antiquity.

Traditional pharmacology and medicine in Africa. Ethnopharmacological themes in sub-Saharan art objects and utensils

Drawing from the general description that ethnopharmacology studies the human use of crude drugs and poisons in a traditional context, ethnopharmacological themes in native art can be defined as themes visualizing different features of traditional medicines and poisons, such as natural sources, methods of preparation, containers, usage and implements, target diseases and effects. This review documents that native African art objects and utensils are a goldmine of such ethnopharmacological themes by focusing on the following subjects: (a) objects related to the use of medicines (sources as well as tools for their collection, preparation and keeping); (b) objects related to the use of poisons (e.g. for ordeals, hunting and fishing); (c) objects related to the use of psychotropic agents (e.g. alcoholic beverages, kola nuts, smoking and snuffing materials); (d) pathological representations (e.g. treponematoses, leprosy, smallpox, swollen abdomen, scrotal enlargement, goiter and distorted faces); and (e) portrayals of certain types of treatment (e.g. topical instillations, perinatal care, and surgery). To avoid the impression that ethnopharmacology has little else to offer than armchair amusement, an epilogue outlines the medical relevance of this interdisciplinary science for Western and African societies.