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Chinhsiao Tseng - One of the best experts on this subject based on the ideXlab platform.

  • Betel Nut chewing and incidence of newly diagnosed type 2 diabetes mellitus in taiwan
    BMC Research Notes, 2010
    Co-Authors: Chinhsiao Tseng
    Abstract:

    Background: Betel Nut chewing is associated with type 2 diabetes mellitus (T2DM) in a recent prevalence study in Taiwan. The present study further investigated its link with the incidence of newly diagnosed T2DM during the years 1992-1996. Methods: Population-based datasets of a sample of 93,484 out of 256,036 diabetic patients from 66 medical settings using the National Health Insurance scheme covering > 96% of the population, published population prevalence of Betel Nut chewing and the governmental census of national population were used for calculation of odds ratios, incidence rates and incidence rate ratios between chewers and never-chewers in the male population for the year 1992 to 1996. Results: Ever chewers among the diabetic patients were younger, more obese and had higher prevalence of parental diabetes than never-chewers (all p values < 0.001). Odds ratios for T2DM for ever chewers vs. neverchewers in the age of < 40, 40-49, 50-59, 60-69 and ≥70 years were 1.06 (0.92-1.23), 1.60 (1.45-1.76), 2.12 (1.88-2.39), 3.58 (3.10-4.13) and 7.14 (5.47-9.31), respectively. In 1996, incidence rates (per 100,000 population) in the respective age groups were 19.1, 251.5, 567.3, 721.7 and 971.4 for never-chewers; and were 30.2, 520.9, 2566.9, 11672.8 and 630.3 for ever chewers. The respective incidence rate ratios were 1.58, 2.07, 4.52, 16.17 and 0.65. The age-specific incidence rates and rate ratios were relatively consistent from 1992 to 1996. The differences in obesity and parental diabetes between ever chewers and never-chewers were mostly not statistically significant after age stratification, suggesting the link could not be attributed to these two factors. Conclusions: Chewing Betel Nut is associated with newly diagnosed T2DM, supporting the suggestion that the habit is diabetogenic.

  • Betel Nut chewing is associated with hypertension in taiwanese type 2 diabetic patients
    Hypertension Research, 2008
    Co-Authors: Chinhsiao Tseng
    Abstract:

    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.

Yvette C. Paulino - One of the best experts on this subject based on the ideXlab platform.

  • epidemiology of areca Betel Nut use in the mariana islands findings from the university of guam university of hawai i cancer center partnership program
    Cancer Epidemiology, 2017
    Co-Authors: Yvette C. Paulino, Eric L Hurwitz, Rachel Novotny, Lynne R Wilkens, Joanne C Ogo, Tristan C Paulino, Ashley Yamanaka, Mary Jane Miller, Neal A Palafox
    Abstract:

    Abstract Background Areca (Betel) Nut is considered a Group 1 human carcinogen shown to be associated with other chronic diseases in addition to cancer. This paper describes the areca (Betel) Nut chewing trend in Guam, and health behaviors of chewers in Guam and Saipan. Methods The areca (Betel) Nut module in the Guam Behavioral Risk Factor Surveillance Survey was used to calculate the 5-year (2011–2015) chewing trend. To assess the association between areca (Betel) Nut chewing and health risks in the Mariana Islands, a cross-section of 300 chewers, ≥18 years old, were recruited from households in Guam and Saipan. Self-reported socio-demographics, oral health behaviors, chronic disease status, diet, and physical activity were collected. Anthropometry was measured. Only areca (Betel) Nut-specific and demographic information were collected from youth chewers in the household. Results The 5-year areca (Betel) Nut chewing prevalence in Guam was 11% and increased among Non-Chamorros, primarily other Micronesians, from 2011 (7%) to 2015 (13%). In the household survey, most adult chewers (46%) preferred areca Nut with Betel leaf, slaked lime, and tobacco. Most youth chewers (48%) preferred areca Nut only. Common adult chronic conditions included diabetes (14%), hypertension (26%), and obesity (58%). Conclusion The 5-year areca (Betel) Nut chewing prevalence in Guam is comparable to the world estimate (10–20%), though rising among Non-Chamorros. Adult and youth chewers may be at an increased risk for oral cancer. Adult chewers have an increased risk of other chronic health conditions. Cancer prevention and intervention strategies should incorporate all aspects of health.

  • areca Betel Nut chewing practices of adults and health behaviors of their children in the freely associated states micronesia findings from the children s healthy living chl program
    Cancer Epidemiology, 2017
    Co-Authors: Yvette C. Paulino, Rachel Novotny, Lynne R Wilkens, Reynolette Ettienne, Moria Shomour, Cecilia Sigrah, Shelley Remengesau, Emihner Johnson, Julia M Alfred, Daisy Gilmatam
    Abstract:

    Abstract Background Chewing areca (Betel) Nut has been deemed carcinogenic. The practice has become a public health concern in Micronesia. The Children's Healthy Living (CHL) Program included an areca (Betel) Nut questionnaire in a survey of household characteristics in the Freely Associated States (FAS). This paper describes areca (Betel) Nut chewing practices of adults and the health behaviors of their children. Methods A cross-section of 1200 children (2–8 year-olds) and their caregivers in Chuuk, Kosrae, Pohnpei, Republic of Palau, Republic of the Marshall Islands (RMI), and Yap were recruited. Socio-demographics, adult areca (Betel) Nut chewing practices, and other health behaviors of children and adults were assessed. Child anthropometric measurements were collected to estimate weight status. Results The FAS areca (Betel) Nut chewing prevalence was 42%, ranging from 3% (RMI) to 94% (Yap). Among chewers, 84% added tobacco, 97% added slaked lime, 85% added Betel leaf, and 24% mixed the components with alcohol. Among FAS children, 95% practiced daily teeth-brushing and 53% visited the dentist annually. Compared to non-chewing households, areca (Betel) Nut chewing households were more likely to have very young children enrolled, more highly educated adults, and members that used tobacco and alcohol. Conclusion The FAS areca (Betel) Nut chewing prevalence (42%) is above the world prevalence of 10–20%, with wide variability across the islands. The oral health findings in this study may inform future oral cancer prevention programs or policies. Regular monitoring of areca (Betel) Nut use is needed to measure the impact of such programs or policies.

  • Betel Nut chewing oral premalignant lesions and the oral microbiome
    PLOS ONE, 2017
    Co-Authors: Brenda Y. Hernandez, Xuemei Zhu, Marc T. Goodman, Paul Mendiola, Katrina Quinata, Robert R Gatewood, Yvette C. Paulino
    Abstract:

    Oral cancers are attributed to a number of causal agents including tobacco, alcohol, human papillomavirus (HPV), and areca (Betel) Nut. Although Betel Nut chewing has been established as an independent cause of oral cancer, the mechanisms of carcinogenesis are poorly understood. An investigation was undertaken to evaluate the influence of Betel Nut chewing on the oral microbiome and oral premalignant lesions. Study participants were recruited from a dental clinic in Guam. Structured interviews and oral examinations were performed. Oral swabbing and saliva samples were evaluated by 454 pyrosequencing of the V3- V5 region of the 16S rRNA bacterial gene and genotyped for HPV. One hundred twenty-two adults were enrolled including 64 current Betel Nut chewers, 37 former chewers, and 21 with no history of Betel Nut use. Oral premalignant lesions, including leukoplakia and submucous fibrosis, were observed in 10 chewers. Within-sample bacterial diversity was significantly lower in long-term (≥10 years) chewers vs. never chewers and in current chewers with oral lesions vs. individuals without lesions. Between-sample bacterial diversity based on Unifrac distances significantly differed by chewing status and oral lesion status. Current chewers had significantly elevated levels of Streptococcus infantis and higher and lower levels of distinct taxa of the Actinomyces and Streptococcus genera. Long-term chewers had reduced levels of Parascardovia and Streptococcus. Chewers with oral lesions had significantly elevated levels of Oribacterium, Actinomyces, and Streptococcus, including Streptococcus anginosus. In multivariate analyses, controlling for smoking, oral HPV, S.anginosus, and S. infantis levels, current Betel Nut chewing remained the only predictor of oral premalignant lesions. Our study provides evidence that Betel Nut chewing alters the oral bacterial microbiome including that of chewers who develop oral premalignant lesions. Nonetheless, whether microbial changes are involved in Betel Nut-induced oral carcinogenesis is only speculative. Further research is needed to discern the clinical significance of an altered oral microbiome and the mechanisms of oral cancer development in Betel Nut chewers.

  • Betel Nut chewing, oral premalignant lesions, and the oral microbiome - Fig 1
    2017
    Co-Authors: Brenda Y. Hernandez, Xuemei Zhu, Marc T. Goodman, Robert Gatewood, Paul Mendiola, Katrina Quinata, Yvette C. Paulino
    Abstract:

    Oral lesions in Betel Nut chewers (left to right, beginning with top left): a. Striated leukoplakia with small ulcerations on buccal mucosae; b. Red erythroplakia of buccal mucosae; c. Mixed erythroplakia of buccal mucosae; d. Pedunculated leukoplakia of buccal mucosae; e. Submucous fibrosis with leukoplakia of buccal mucosae

  • screening for oral potentially malignant disorders among areca Betel Nut chewers in guam and saipan
    BMC Oral Health, 2014
    Co-Authors: Yvette C. Paulino, Saman Warnakulasuriya, Robert R Gatewood, Eric L Hurwitz, Kenneth D Pierson, Lynnette F Tenorio, Rachel Novotny, Neal A Palafox, Lynne R Wilkens, Grazyna Badowski
    Abstract:

    Background The Mariana Islands, including Guam and Saipan, are home to many ethnic subpopulations of Micronesia. Oral cancer incidence rates vary among subpopulations, and areca (Betel) Nut chewing, a habit with carcinogenic risks, is common. Our objectives were to conduct a screening program to detect oral potentially malignant disorders (OPMD) in Betel Nut chewers, measure their Betel Nut chewing practices, and assess the prevalence of the oral human papillomavirus (HPV) infection in a subset of Betel Nut chewers in these islands.

M Mariatti - One of the best experts on this subject based on the ideXlab platform.

  • thermo physical thermal degradation and flexural properties of Betel Nut husk fiber reinforced vinyl ester composites
    Polymer Composites, 2016
    Co-Authors: L Yusriah, E S Zainudin, S M Sapuan, M Mariatti, Mohammad Jawaid
    Abstract:

    This study aims to investigate the thermo-physical, mechanical, and thermal degradation properties of Betel Nut husk (BNH) fiber reinforced vinyl ester (VE) composites. These properties were evaluated as a function of fiber maturity, fiber content, and fiber orientation. Thermo-physical properties were analyzed experimentally using a hot disk TPS method. The introduction of BNH was found to reduce the thermal conductivity of neat VE. The thermal conductivity and thermal diffusivity of BNH reinforced VE composites decreased with the increase in fiber content. Short fiber BNH reinforced VE composites showed the lowest thermal conductivity as compared to the unidirectional and random nonwoven composites. The TGA analysis shows lower resin transition peak for the BNH reinforced VE composites than the peak of neat VE. Fiber maturity had a notable effect on the flexural modulus of the BNH fiber reinforced VE composites. Incorporation of 10 wt% BNH fibers into the composite has increased the composites' flexural modulus by 46.37%. However, further increases in the fiber content reduced both flexural strength and modulus of the composites.

  • characterization of physical mechanical thermal and morphological properties of agro waste Betel Nut areca catechu husk fibre
    Journal of Cleaner Production, 2014
    Co-Authors: L Yusriah, E S Zainudin, S M Sapuan, M Mariatti
    Abstract:

    This paper investigates the physical, thermal, mechanical and morphological properties of Betel Nut husk fibre, in order to assess their suitability as lignocellulosic reinforcement for polymer composites. Betel Nut husk (BNH) fibres of three different stages of maturity were evaluated to study the effect of fibre maturity on the thermal, physical and mechanical properties of BNH fibre. The thermal stability of BNH fibre was studied using the thermogravimetric analysis (TGA) technique. It was found that the thermal stability of the BNH fibre is influenced by the maturity of the BNH fibre due to the different amounts of cellulose, hemicellulose, lignin, and moisture in the BNH fibre at each stage of maturity (raw, ripe, matured). The BNH fibres showed decrease in fibre length and fibre diameter, and increase in density with the increase in fibre maturity. SEM micrographs of BNH fibre surface revealed the existence of rough and perforated surface of BNH fibre. Whereas, the cross-sectional of the BNH fibre showed that the raw BNH fibres were observed with bigger lumen, whilst ripe BNH fibre exhibits a slightly smaller and elongated lumen. In contrast, matured BNH fibre showed more compact structures instead of hollow-like lumen structures. In terms of mechanical properties, the BNH fibre tensile properties were found to be comparable to coir and kenaf fibre, which have been widely used as reinforcement in polymer composites.

  • exploring the potential of Betel Nut husk fiber as reinforcement in polymer composites effect of fiber maturity
    Procedia Chemistry, 2012
    Co-Authors: L Yusriah, E S Zainudin, S M Sapuan, M Mariatti
    Abstract:

    This paper presents investigations on the effect of three different stages of fiber maturity (unripe, ripe and dried) on the physical, morphological and mechanical properties of Betel Nut husk (Areca catechu) (BNH). Density analysis, optical observation, moisture content and water absorption study were carried out to evaluate physical properties of BNH fiber. The fiber length and diameter were decreased with the increase of maturity stage from raw to ripe, while the density increased from raw to ripe. Mechanical properties of BNH fiber at different maturity were determined from single-fiber tensile tests where tensile strength, tensile modulus and elongation at break were found varied at each stages of fiber maturity. The difference in tensile strength of raw, ripe and dried BNH fiber is attributed to the structural changes in the plant cell wall during the ripening stage from immature to fully ripening stages. Modulus of natural fiber is also related to the lignin content in the fiber. Water absorption was found to be the highest for raw BNH fiber and the lowest water absorption was observed in dried BNH fiber. Highest moisture content was observed in ripe BNH fiber and the lowest was in dried BNH fiber due to moisture lost during fruit ripening. The diameter of lumen in raw BNH is larger than that of lumen of ripe BNH fiber, while dried BNH fiber showed more compacted structure of fiber.

B J Boucher - One of the best experts on this subject based on the ideXlab platform.

  • areca catechu Betel Nut induced whole transcriptome changes associated with diabetes obesity and metabolic syndrome in a human monocyte cell line
    bioRxiv, 2020
    Co-Authors: Shirleny Cardosa, B J Boucher, W Ogunkolade, Robert Lowe, Emanuel Savage, Charles A Mein, G A Hitman
    Abstract:

    Betel-Nut consumption is the fourth most common addictive habit globally and there is good evidence to link it with obesity, type 2 diabetes and the metabolic syndrome. We adopted a genome-wide transcriptomic approach in a human monocyte cell line incubated with arecoline and its nitrosated products to identify gene expression changes relevant to obesity, type 2 diabetes and the metabolic syndrome. The THP1 monocyte cell line was incubated separately with arecoline and 3-methylnitrosaminopropionaldehyde (MNPA) in triplicate for 24 hours and pooled cDNA indexed paired-end libraries were sequenced (Illumina NextSeq 500). After incubation with arecoline and MNPA, 15 and 39 genes respectively had significant changes in their expression (q<0.05, log fold change 1.5). Eighteen of those genes have reported associations with type 2 diabetes and obesity in humans; of these genes there was strong evidence to implicate CLEC10A, MAPK8IP1, NEGR1, NQ01 and INHBE. In summary, these pilot studies have identified a large number of genes whose expression was changed significantly in human TPH1 cells following incubation with arecoline or with 3-methylnitrosaminopropionaldehyde. These findings suggest that further investigation of these genes in Betel-quid chewers with obesity and/or type 2 diabetes is warranted.

  • vitamin d metabolism in peripheral blood mononuclear cells is influenced by chewing Betel Nut areca catechu and vitamin d status
    The Journal of Clinical Endocrinology and Metabolism, 2006
    Co-Authors: W Ogunkolade, B J Boucher, N Mannan, Stephen A Bustin, J M Burrin, Kate Noonan, G A Hitman
    Abstract:

    Context: Vitamin D deficiency, common in South Asians, is a risk factor for metabolic syndrome, type 2 diabetes, and ischemic heart disease. Vitamin D receptor (VDR) activation depends on activated vitamin D [1,25-dihydroxyvitamin D (1,25(OH)2D)] concentration, reflecting opposing actions of 25-hydroxyvitamin D-1α-hydroxylase [1-α(OH)ase] for formation and 25(OH)D-24-hydroxylase [24(OH)ase] for catabolism. We previously reported that circulating 1,25(OH)2D contributed to determination of VDR-protein levels and VDR genotype was a determinant of both VDR mRNA and VDR-protein in South Asians. Objective: We hypothesized that chewing Betel Nut, an addictive habit common throughout South Asian communities, contributes to hypovitaminosis-D by modulating the enzymes regulating circulating 1,25(OH)2D concentration. Design: Peripheral blood mononuclear cell (PBMC) 1-α(OH)ase and 24(OH)ase mRNA concentrations were measured and examined in relation to cross-sectional data on the vitamin-D axis, diet, smoking, and bet...

  • increased waist size and weight in relation to consumption of areca catechu Betel Nut a risk factor for increased glycaemia in asians in east london
    British Journal of Nutrition, 2000
    Co-Authors: N Mannan, B J Boucher, S J W Evans
    Abstract:

    Type 2 diabetes is commoner in Asians than Caucasians. Many nitrosamines are diabetogenic,causing both type 2 and type 1 diabetes. Of CD1 mice fed with Betel-Nut or associatednitrosamines 8⋅5% develop glucose intolerance with marked obesity. Glycaemia and anthropo-metric risk markers for type 2 diabetes were therefore examined in relation to Betel usage in 993‘healthy’ Bangladeshis by one bilingual research-worker (N.M.). Of these, 12% had knowndiabetes. A further 145 of 187 subjects ‘at-risk’ of diabetes (spot glucose.6⋅5mmol/l ,2h afterfood, or .4⋅5mmol/l .2h after food) had a second blood glucose sample taken; sixty-one wereconfirmed as ‘at-risk’, and had an oral glucose tolerance test; nine new diabetics were identified.Multiple regression analysis showed that spot blood glucose values decreased with time aftereating (P=0⋅0005) and increased independently with waist size (P=0⋅0005) and age (P=0⋅0005)without relationships to other aspects of the diet, season or smoking. Waist size was stronglyrelated to Betel usage independent of other factors such as age. Betel use interacted with sex,relating to increasing glycaemia only in females. Since waist and age were the major markers ofincreasing glycaemia we suggest that Betel chewing, a habit common to about 10% of the worldpopulation (more than 200 million people) may contribute to the risk of developing type 2diabetes mellitus.Central obesity: Betel-Nut: Diabetes: Asians

  • Betel Nut areca catechu consumption and the induction of glucose intolerance in adult cd1 mice and in their f1 and f2 offspring
    Diabetologia, 1994
    Co-Authors: B J Boucher, S W B Ewen, J M Stowers
    Abstract:

    Many mutagenic nitroso compounds are also diabetogenic. Betel-Nut (Areca catechu) chewing populations have an increased incidence of foregut cancers related to Betel-Nut nitrosamines which suggests that Betel consumption could be diabetogenic. Young adult CD1 mice with a low spontaneous incidence of diabetes were fed Betel Nut in standard feed for 2–6 days. Single point (90 min) intra-peritoneal glucose tolerance tests were used to follow glucose tolerance up to 6 months of age. Glucose intolerance was defined as over 3 SD above mean control values. Glucose intolerance was found in 3 of 51 male and 4 of 33 female adult mice which were fed the Betel diet (p<0.01). Studies on the progeny of these mice are presented separately for animals studied in Aberdeen (Group 1) and London (Group 2). In matings of Group 1 Betel-fed parents glucose intolerance was found in 4 of 25 male and 1 of 22 female F1 offspring, with significant hyperglycaemia in F1 males born to hyperglycaemic but not to normoglycaemic mothers (p<0.01). In the F2 generation 4 of 23 males and 1 of 16 females and in the F3 generation 1 of 16 males and 0 of 20 females were glucose intolerant. In the Group 2 studies where Betel-fed parents were mated to normal controls glucose intolerance was found in 10 of 35 male and 10 of 33 female Fl progeny (p<0.005), and mean islet areas were increased in offspring of Betel-fed parents (p<0.001). The total incidence of glucose intolerance in Fl progeny from studies in Groups 1 and 2 was 14 of 60 males and 11 of 55 females (p<0.005). Insulin dependence did not develop in the glucose-intolerant Betel-fed animals or their descendants; affected animals appearing well built and active. The development of glucose intolerance in F1 offspring was not dependent on maternal glucose intolerance or on maternal Betel-feeding, and 90-min glucose levels of F1 offspring were directly related to paternal but not to maternal glycaemia (p<0.01). Our findings suggest that BetelNut (Areca) consumption may be diabetogenic and induce an inheritable abnormality. The hypothesis is of interest in view of the widespread habit of Betel consumption and of the strategies known to inhibit the induction of experimental diabetes by diabetogenic nitroso compounds.

G A Hitman - One of the best experts on this subject based on the ideXlab platform.

  • areca catechu Betel Nut induced whole transcriptome changes associated with diabetes obesity and metabolic syndrome in a human monocyte cell line
    bioRxiv, 2020
    Co-Authors: Shirleny Cardosa, B J Boucher, W Ogunkolade, Robert Lowe, Emanuel Savage, Charles A Mein, G A Hitman
    Abstract:

    Betel-Nut consumption is the fourth most common addictive habit globally and there is good evidence to link it with obesity, type 2 diabetes and the metabolic syndrome. We adopted a genome-wide transcriptomic approach in a human monocyte cell line incubated with arecoline and its nitrosated products to identify gene expression changes relevant to obesity, type 2 diabetes and the metabolic syndrome. The THP1 monocyte cell line was incubated separately with arecoline and 3-methylnitrosaminopropionaldehyde (MNPA) in triplicate for 24 hours and pooled cDNA indexed paired-end libraries were sequenced (Illumina NextSeq 500). After incubation with arecoline and MNPA, 15 and 39 genes respectively had significant changes in their expression (q<0.05, log fold change 1.5). Eighteen of those genes have reported associations with type 2 diabetes and obesity in humans; of these genes there was strong evidence to implicate CLEC10A, MAPK8IP1, NEGR1, NQ01 and INHBE. In summary, these pilot studies have identified a large number of genes whose expression was changed significantly in human TPH1 cells following incubation with arecoline or with 3-methylnitrosaminopropionaldehyde. These findings suggest that further investigation of these genes in Betel-quid chewers with obesity and/or type 2 diabetes is warranted.

  • vitamin d metabolism in peripheral blood mononuclear cells is influenced by chewing Betel Nut areca catechu and vitamin d status
    The Journal of Clinical Endocrinology and Metabolism, 2006
    Co-Authors: W Ogunkolade, B J Boucher, N Mannan, Stephen A Bustin, J M Burrin, Kate Noonan, G A Hitman
    Abstract:

    Context: Vitamin D deficiency, common in South Asians, is a risk factor for metabolic syndrome, type 2 diabetes, and ischemic heart disease. Vitamin D receptor (VDR) activation depends on activated vitamin D [1,25-dihydroxyvitamin D (1,25(OH)2D)] concentration, reflecting opposing actions of 25-hydroxyvitamin D-1α-hydroxylase [1-α(OH)ase] for formation and 25(OH)D-24-hydroxylase [24(OH)ase] for catabolism. We previously reported that circulating 1,25(OH)2D contributed to determination of VDR-protein levels and VDR genotype was a determinant of both VDR mRNA and VDR-protein in South Asians. Objective: We hypothesized that chewing Betel Nut, an addictive habit common throughout South Asian communities, contributes to hypovitaminosis-D by modulating the enzymes regulating circulating 1,25(OH)2D concentration. Design: Peripheral blood mononuclear cell (PBMC) 1-α(OH)ase and 24(OH)ase mRNA concentrations were measured and examined in relation to cross-sectional data on the vitamin-D axis, diet, smoking, and bet...