Publications by authors named "Yoon-Hee Cho"

96 Publications

Exposure to polycyclic aromatic hydrocarbons and volatile organic compounds is associated with a risk of obesity and diabetes mellitus among Korean adults: Korean National Environmental Health Survey (KoNEHS) 2015-2017.

Int J Hyg Environ Health 2021 Dec 2;240:113886. Epub 2021 Dec 2.

Department of Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea; Devision of Endocrinology, Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul, South Korea. Electronic address:

Environmental pollutants have been known to increase the risks of not only respiratory and cardiovascular disease but also metabolic diseases such as obesity and diabetes mellitus (DM). Polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) such as benzene and toluene are major constituents of environmental pollution. In the present study, we employed the population of the Korean National Environmental Health Survey (KoNEHS) Cycle 3 conducted between 2015 and 2017, and assessed the associations of urinary biomarkers for PAHs and VOCs exposure with obesity and DM. A total of 3787 adult participants were included and the urinary concentrations of four PAH metabolites and two VOC metabolites were measured. For correcting urine dilution, a covariate-adjusted standardization method was used. The highest quartiles of urinary 2-hydroxynaphthalene (2-NAP) [OR (95% confidence interval (CI)) = 1.46 (1.13, 1.87)] and sum of PAH metabolites [OR (95% CI) = 1.45 (1.13, 1.87)] concentrations were associated with a higher risk of obesity [body mass index (BMI)≥25 kg/m]. BMI was positively associated with urinary 2-NAP [β (95% CI) = 0.25 (0.09, 0.41), p = 0.003] and sum of PAH metabolites [β (95% CI) = 0.29 (0.08, 0.49), p = 0.006] concentrations. The risk of DM was increased with increasing quartile of 2-hydroxyfluorene (2-OHFlu) and trans, trans-muconic acid (t,t-MA) (p for trend<0.05 and < 0.001, respectively). The highest quartile of t,t-MA showed a significantly higher risk of DM [OR (95% CI) = 2.77 (1.74, 4.42)] and obesity [OR (95% CI) = 1.42 (1.06, 1.90)]. Urinary t,t,-MA level was positively associated with BMI [(β (95% CI) = 0.51 (0.31, 0.71), p < 0.001] and non-alcoholic fatty liver disease index [(β (95% CI) = 0.09 (0.06, 0.12), p < 0.001]. In conclusion, the benzene metabolites t,t-MA and PAH metabolite 2-OHFlu were associated with an increased risk of DM. Urinary biomarkers for PAHs and VOCs were positively associated with BMI in the Korean adult population. Further studies to validate these observations in other populations are warranted.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijheh.2021.113886DOI Listing
December 2021

Do Alcohol Prevention Programs Influence Adolescents' Drinking Behaviors? A Systematic Review and Meta-Analysis.

Int J Environ Res Public Health 2021 08 12;18(16). Epub 2021 Aug 12.

Department of Nursing, College of Nursing, Dankook University, Cheonan 31116, Korea.

This study analyzed the effects of various alcohol prevention programs on the drinking behavior of adolescents. There were seven electronic databases used for the literature search. A systematic review and meta-analysis are employed for works published in Korean and English from January 2010 to April 2021, with strict inclusion criteria yielding 12 papers in the review. The type of alcohol prevention interventions included educational and motivational interventions. Six studies had more than 500 participants each, and five studies had more than 10 participating schools. The programs did not effectively reduce the frequency of drinking or binge drinking of adolescents but significantly reduced the amount of alcohol consumed. Based on the results of this study, when planning alcohol prevention programs for adolescents, it is necessary to adopt a multi-level approach, including the engagement of parents and the community.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph18168524DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8392207PMC
August 2021

Lead, mercury, and cadmium exposures are associated with obesity but not with diabetes mellitus: Korean National Environmental Health Survey (KoNEHS) 2015-2017.

Environ Res 2022 03 14;204(Pt A):111888. Epub 2021 Aug 14.

Department of Environmental Health Sciences, Soonchunhyang University, Asan, South Korea. Electronic address:

Background: Associations of heavy metal exposures with obesity and obesity-related traits have been suggested, while those with nonalcoholic fatty liver disease (NAFLD) and diabetes mellitus (DM) are often inconsistent.

Methods: This study included 3787 adults aged ≥19 years who participated in the Korean National Environmental Health Survey 2015-2017, and investigated the association of toxic heavy metals with metabolic diseases. Lead (Pb), mercury (Hg), and cadmium (Cd) were measured either in urine (uHg, uCd) or total blood (bPb, bHg). Body mass index (BMI) was calculated, and DM cases were identified through a self-answered medication history. Hepatic Steatosis Index (HSI) as a surrogating index of NAFLD, was calculated using hepatic enzyme measurements, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT).

Results: Adults in the highest quartile of bPb, bHg, and uHg showed significantly elevated odds of obesity (BMI ≥25 kg/m), compared to the lowest quartile (OR 1.58 for bPb, 1.92 for bHg, and 1.81 for uHg). HSI was positively correlated with bHg, uHg, and uCd concentrations. The odds of NAFLD (HSI ≥36) were also increased with increasing quartile of bHg, uHg, and uCd concentrations. For DM, bPb showed a significant negative association, while bHg and uCd exhibited non-monotonic and inconclusive associations.

Conclusions: Among the general adult population of Korea, both Pb and Hg exposures were associated with an increased risk of obesity. In addition, both Hg and Cd exposures were associated with increased odds of NAFLD. These metals, however, were not associated with an increased risk of DM.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envres.2021.111888DOI Listing
March 2022

Placental Transfer and Composition of Perfluoroalkyl Substances (PFASs): A Korean Birth Panel of Parent-Infant Triads.

Toxics 2021 Jul 14;9(7). Epub 2021 Jul 14.

Departments of Obstetrics and Gynecology, Inje University, Ilsan Paik Hospital, Goyang-si 10380, Korea.

Exposure to perfluoroalkyl substances (PFASs) is of public concern due to their persistent exposure and adverse health effects. Placental transfer of PFASs is an important excretion pathway of these chemicals in pregnant women and exposure route in fetuses. We measured PFAS concentrations in maternal, paternal, and umbilical cord serum collected from 62 pregnant Korean women and matched biological fathers of the fetuses. Placental transfer rates (cord to maternal serum ratio) of PFASs were also calculated. Demographics and pregnancy-related factors determining the placental transfer rates were identified using linear regression models. Maternal, paternal, and cord serum showed different PFASs compositions. Among the PFASs, perfluorooctane sulfonate (PFOS) showed the highest concentrations in maternal and paternal serum, while perfluorooctanoic acid (PFOA) showed the highest concentration in cord serum. There was a higher proportion of perfluoroalkyl carboxylic acids (PFCAs) with 9-12 carbon chains than those with 13-14 carbon chains in maternal and paternal serum, but this proportion was in the opposite direction in cord serum. PFOA and perfluorohexane sulfonate (PFHxS) had higher placental transfer rates (means of 0.32 and 0.36, respectively) than PFOS (mean of 0.12), which is in line with the results of previous studies. Gestational age and birth weight were positively associated with placental transfer rate of PFOA, PFHxS, and PFOS, while pre-pregnant BMI and weight were inversely associated with PFOS. This study showed that placental transfer of PFASs differs by compounds and is associated with pregnancy-related factors. Further studies on novel PFASs are warranted for Korean pregnant women.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxics9070168DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8309930PMC
July 2021

Metabolic Evidence Rather Than Amounts of Red or Processed Meat as a Risk on Korean Colorectal Cancer.

Metabolites 2021 Jul 16;11(7). Epub 2021 Jul 16.

Department of Toxicology, College of Pharmacy, Sookmyung Women's University, Seoul 04310, Korea.

The incidence of colorectal cancer (CRC) has increased in Korea, a newly- Asian country, with the dramatic increase of meat intake. To assess the risks of red or processed meat consumption on CRC, we performed a case-control study with biological monitoring of urinary1-OHP, PhIP, and MeIQx for the meat exposure; dG-C8 MeIQx and dG-C8 PhIP for HCA-induced DNA adducts; and homocysteine and C-reactive protein (CRP) in blood as well as malondialdehyde (MDA) and 31fatty acids in urine for inflammation and lipid alteration. We further analyzed global DNA methylation and expression of 15 CRC-related genes. As a result, the consumption of red or processed meat was not higher in the cases than in the controls. However, urinary MeIQx and PhIP were associated with the intake of red meat and urinary 1-OHP. MDA and multiple fatty acids were related to the exposure biomarkers. Most of the 31 fatty acids and multiple saturated fatty acids were higher in the cases than in the controls. Finally, the cases showed upregulation of , which is related to pro-inflammatory fatty acids. This study describes indirect mechanisms of CRC via lipid alteration with a series of processes including exposure to red meat, alteration of fatty acids, and relevant gene expression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/metabo11070462DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8303103PMC
July 2021

Potential of an Enzyme Mixture of Glucose Oxidase, Glucosyl Transferase, and Fructosyl Transferase as an Antidiabetic Medicine.

Biomedicines 2021 Jun 28;9(7). Epub 2021 Jun 28.

Department of Internal Medicine, Endocrinology, Institute of Endocrine Research, Yonsei University College of Medicine, Seoul 03722, Korea.

An enzyme mixture (EM) of glucose oxidase, glucosyl transferase, and fructosyl transferase can regulate glucose absorption into the body by converting carbohydrates in food to indigestible oligosaccharides. We evaluated the antidiabetic effects of repeated oral administration of EM in db/db mice. Seven-week-old db/db mice were divided into control, voglibose, and EM groups. Drugs were administered orally mixed with limited feed for one month. Glucose levels were measured every week. A meal tolerance test was conducted after overnight fasting, before the mice were sacrificed. There were no differences in body weight or food intake between the groups. EM treatment reduced blood glucose levels compared with those in the control group. Blood glucose levels during the meal tolerance test were significantly lower in the EM group than those in the control group. A significant decrease in triglyceride level and a tendency for decreased low-density lipoprotein were observed in the EM group compared with in the control group. The Bacteroidetes-to-Firmicutes ratio was higher in the EM group than that in the control group. EM may be useful for people at risk of hyperglycemia or diabetes who need to safely regulate their blood glucose levels. EM may also improve lipid and gut microbiota profiles.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/biomedicines9070745DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8301424PMC
June 2021

Urinary parabens and their potential sources of exposure among Korean children and adolescents: Korean National Environmental Health Survey 2015-2017.

Int J Hyg Environ Health 2021 07 10;236:113781. Epub 2021 Jun 10.

Environmental Health Research Division, National Institute of Environmental Research, Ministry of Environment, Incheon, Republic of Korea. Electronic address:

Parabens are used as a preservative in several consumer products including cosmetics, personal care products, and medicinal products. These chemicals have been suspected for estrogenicity and potential adverse endocrine outcomes in humans. For the first time, exposure profiles and potential sources of major parabens are investigated for a nationally representative population of children and adolescents of Korea. In addition, major determinants of urinary paraben levels were identified. For this purpose, the children, and adolescents (n = 2355, 3-18 years of age) who participated in the Korean National Environmental Health Survey cycle 3 (2015-2017) were studied. Adjusted multiple linear regression models were employed to investigate the relationships of several potential demographic and behavioral determinants of exposure, with the urinary levels of three parabens; methyl, ethyl, and propyl paraben. Methyl and propyl paraben levels of the Korean children and adolescents were comparable to those of the US, but the high exposure group (95th percentile) showed much higher levels of exposure. Moreover, urinary ethyl paraben levels are always higher than those of other countries. The uses of personal care products including liquid soaps, fragrance products, nail polish, or antiseptic products were significantly associated with urinary paraben levels. In addition, dietary sources such as fast food and canned food consumption were identified as major contributors to ethyl paraben levels. For methyl and propyl parabens, the use of fever medications and ointments were identified as major determinants of the exposure, especially among the younger children of 3-5 years of age. These observations are related to the Korean regulations that permit the use of the parabens as preservatives in foods and medications. The findings demonstrate that the exposure profile of parabens among Korean children are unique, and mitigation efforts for some parabens are required in Korea. Further studies are warranted to confirm the exposure sources of parabens and to develop mitigation measures among Korean children and adolescents.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijheh.2021.113781DOI Listing
July 2021

Recruitment and enrollment of participants in an online diabetes self-management intervention in a virtual environment.

Contemp Clin Trials 2021 06 20;105:106399. Epub 2021 Apr 20.

Duke University School of Nursing, DUMC 3322, 307 Trent Drive, Durham, NC 27710I, USA; Jane and Robert Cizik School of Nursing, The University of Texas Health Science Center at Houston, 6901 Bertner Ave. SON-539D, Houston, TX 77030, USA.

Effective recruitment of research participants is essential for successful randomized controlled trials and remains one of the most challenging and labor-intensive aspects of conducting research. The purpose of this manuscript is to describe recruitment methods for this two-group, internet-based intervention trial and enrollment status in relation to recruitment methods, accounting for accrual rates and recruitment costs and to discuss our recruitment results and limitations informed by the Clinical Trials Transformation Initiative (CTTI) team's evidence and expert-based recommendations for recruitment. The primary study was a two-group randomized controlled trial designed to evaluate the efficacy of a virtual environment, Diabetes LIVE©, compared to a traditional website format to provide diabetes self-management education and support to adults with type 2 diabetes. Our recruitment experience was labor-intensive, multimodal, and required multiple iterations throughout the study to meet recruitment goals. To allow for more efficient and realistic budgets aligned with funding, researchers should engage stakeholders in recruitment planning and monitor and report personnel time and cost by recruitment methods. To allow for more efficient and effective recruitment into meaningful clinical trials and of interest to participants, researchers should use a participative approach during all study phases, including question development.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2021.106399DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8172527PMC
June 2021

Danshen Extracts Prevents Obesity and Activates Mitochondrial Function in Brown Adipose Tissue.

Endocrinol Metab (Seoul) 2021 Feb 24;36(1):185-195. Epub 2021 Feb 24.

Division of Endocrinology and Metabolism, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.

Background: Danshen has been widely used in oriental medicine to improve body function. The purpose of this study is to investigate the effect of water-soluble Danshen extract (DE) on weight loss and on activation proteins involved in mitochondrial biogenesis in brown adipose tissue (BAT) in obese mice.

Methods: BAT was isolated from 7-week-old male Sprague-Dawley rats, and expression of proteins related to mitochondrial biogenesis was confirmed in both brown preadipocytes and mature brown adipocytes treated with DE. For the in vivo study, low-density lipoprotein receptor knock out mice were divided into three groups and treated for 17 weeks with: standard diet; high fat diet (HFD); HFD+DE. Body weight was measured every week, and oral glucose tolerance test was performed after DE treatment in streptozotocin-induced diabetic mice. To observe the changes in markers related to thermogenesis and adipogenesis in the BAT, white adipose tissue (WAT) and liver of experimental animals, tissues were removed and immediately frozen in liquid nitrogen.

Results: DE increased the expression of uncoupling protein 1 and peroxisome proliferator-activated receptor gamma coactivator 1-alpha in brown preadipocytes, and also promoted the brown adipocyte differentiation and mitochondrial function in the mature brown adipocytes. Reactive oxygen species production in brown preadipocytes was increased depending on the concentration of DE. DE activates thermogenesis in BAT and normalizes increased body weight and adipogenesis in the liver due to HFD. Browning of WAT was increased in WAT of DE treatment group.

Conclusion: DE protects against obesity and activates mitochondrial function in BAT.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3803/EnM.2020.835DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7937848PMC
February 2021

Association of exposure to polycyclic aromatic hydrocarbons and heavy metals with thyroid hormones in general adult population and potential mechanisms.

Sci Total Environ 2021 Mar 13;762:144227. Epub 2020 Dec 13.

Department of Environmental Health Sciences, Soonchunhyang University, Asan, Republic of Korea. Electronic address:

Air pollution and fuel emissions are the common sources of human exposure to polycyclic aromatic hydrocarbons (PAHs) and heavy metals. Several studies have suggested potential associations between PAHs/heavy metals and thyroid hormones, however, reports have been inconsistent. In this study, we employed a subpopulation of the adults (n = 1254) who participated in the Korean National Environmental Health Survey 2015-2017, and investigated the association of PAHs and major heavy metals with thyroid hormones, and explored the underlying mechanisms of thyroid disruption. Four PAH metabolites and three heavy metals of lead (Pb), mercury (Hg), and cadmium (Cd) were measured either in urine or in total blood. In addition, thyroid hormones (T3 and T4), TSH, thyroxine-binding globulin (TBG), and thyroid autoantibodies were measured, and peripheral deiodinase activity (G) and thyroid's secretory capacity (G) were calculated. Urinary Hg was negatively associated with total T3 in both males and females, while it was positively associated with total T4 among females only. Urinary Hg was related to decreased G and increased G in both sexes. In contrast, urinary Cd was positively associated with total T3 and G in both male and female populations. Urinary Cd also showed a positive association with thyroid autoantibodies, but only in males. A multi-factor model considering co-exposure to multiple chemicals also resulted in similar associations. Among the measured PAH metabolites, only urinary 1-hydroxypyrene showed a negative association with total T3 in males. However, this association was marginal, and disappeared in a multi-chemical model. The present observations are suggestive that exposures to Hg and Cd might disrupt thyroid hormones, possibly through an alteration of deiodinase activity. Association of PAH exposure with thyroid hormone appears to be insignificant.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2020.144227DOI Listing
March 2021

Associations of Relative Humidity and Lifestyles with Metabolic Syndrome among the Ecuadorian Adult Population: Ecuador National Health and Nutrition Survey (ENSANUT-ECU) 2012.

Int J Environ Res Public Health 2020 12 3;17(23). Epub 2020 Dec 3.

Department of Public Health, Graduate School of Public Health, Seoul National University, Seoul 08826, Korea.

The effects of the physical environment on metabolic syndrome (MetS) are still largely unexplained. This study aimed to analyze the associations of relative humidity of residence, lifestyles, and MetS among Ecuadorian adults. Data from 6024 people aged 20 to 60 years were obtained from an Ecuador national population-based health and nutrition survey (i.e., ENSANUT-ECU, 2012) and the mean annual relative humidity (%) from the Ecuador National Institute for Meteorology and Hydrology (2012). Odds ratio (OR) with 95% confidence intervals (CI) for MetS according to groups of relative humidity were calculated using multiple logistic regression. Living in high relative humidity (>80%) increased ORs of reduced high-density lipoprotein (HDL) cholesterol (1.25; 95 % CI, 1.06-1.56) and MetS (OR = 1.20; 95 % CI,1.01-1.42) in women. Furthermore, physically active men living in high relative humidity showed lower OR of elevated triglycerides (0.56; 95 % CI,0.37-0.85) while menopausal women living in high relative humidity showed increased ORs of MetS (5.42; 95 % CI, 1.92-15.27), elevated blood pressure (3.10; 95 % CI, 1.15-8.35), and increased waist circumference (OR = 1.34; 95 % CI, 1.09-1.63). Our results show that residence in high relative humidity and menopausal status increase ORs of MetS and its components in Ecuadorian women; however, physical activity significantly reduces the OR of elevated triglycerides in men. The obtained findings may help make public health policies regarding environmental humidity management, nutritional education, menopausal care, and physical activity promotion to prevent the onset of MetS among Ecuadorian adults.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph17239023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7731373PMC
December 2020

Associations of urinary concentrations of phthalate metabolites, bisphenol A, and parabens with obesity and diabetes mellitus in a Korean adult population: Korean National Environmental Health Survey (KoNEHS) 2015-2017.

Environ Int 2021 01 2;146:106227. Epub 2020 Nov 2.

Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Devision of Endocrinology, Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul, Republic of Korea. Electronic address:

Phthalates and bisphenol A (BPA) have been suspected as risk factors for obesity and diabetes mellitus (DM) among humans. However, associations between phthalates and environmental phenols are often inconsistent across different populations. In this study, we recruited the adult population (n = 3782) of the Korean National Environmental Health Survey (KoNEHS) 2015-2017 (Cycle 3) and assessed the associations between urinary biomarkers of phthalate, BPA, and paraben exposure with obesity and DM. A potential collider issue with the use of urinary creatinine (Cr) or specific gravity (SG) exists when adjusting urinary dilution; therefore, a covariate-adjusted standardization (CAS) was employed for adjustment, and the results were compared. In the present population, the direction of the association often varied depending on the choices made to adjust urinary dilution. When using CAS, the direction of association resembled those of previously reported experimental observations. With Cr or SG adjustment, ORs for obesity decreased in the highest quartiles of monocarboxyoctyl phthalate (MCOP) [OR (95% CI) = Cr: 0.71 (0.54, 0.93); SG: 0.68 (0.52, 0.90)], monocarboxy-isononyl phthalate (MCNP) [OR (95% CI) = Cr: 0.67 (0.52, 0.87); SG: 0.68 (0.52, 0.89)], and mono(3-carboxylpropyl) phthalate (MCPP) in the urine [OR (95% CI) = Cr: 0.60 (0.47, 0.76); SG: 0.61 (0.48, 0.77)]; however, with CAS, these negative associations disappeared. Instead, mono-benzyl phthalate (MBzP) [OR (95% CI) = 1.31 (1.03, 1.66)], BPA [OR (95% CI) = 1.62 (1.27, 2.06)], or ethyl paraben (EtP) [OR (95% CI) = 1.51 (1.19, 1.91)] concentrations in the highest quartile showed positive associations with a higher risk of obesity. On the other hand, for DM, an overall decrease in ORs was observed for phthalate metabolites and BPA following SG adjustment and disappeared with CAS adjustment. In addition, the highest quartiles of BPA, methyl paraben (MeP), and ethyl paraben (EtP) showed a significantly higher risk of DM than those in the lowest quartiles following CAS [OR (95% CI) = BPA: 1.65 (1.06, 2.59); MeP: 1.68 (1.08, 2.60); and EtP: 2.74 (1.77, 4.24), respectively]. The present observations outline the importance of using an appropriate adjustment method for urinary dilution in association studies on obesity and DM. In addition, several phthalates, BPA, and parabens were identified as potential chemical risk factors for these outcomes. Further studies are warranted in other populations to confirm these observations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envint.2020.106227DOI Listing
January 2021

Low Elevation and Physical Inactivity are Associated with a Higher Prevalence of Metabolic Syndrome in Ecuadorian Adults: A National Cross-Sectional Study.

Diabetes Metab Syndr Obes 2020 25;13:2217-2226. Epub 2020 Jun 25.

Department of Public Health, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea.

Background: Elevation and health-related lifestyles have been associated with the development of metabolic syndrome (MetS). However, such associations have not been investigated extensively in a global context. The present study aimed to determine the associations among elevation of residence, health-related lifestyles, and the risk of MetS in an Ecuadorian adult population.

Subjects And Methods: This cross-sectional study was conducted utilizing secondary data from the 2012 Ecuador National Health and Nutrition Survey (ENSANUT-ECU). A total of 6024 adults (1964 men and 4060 women) 20 to 60 years old were included in the study. Elevation was obtained by georeferencing techniques and categorized into low (0-2000 masl) and high (>2001 masl). Dietary intake was measured using a 24-hour recall and health-related lifestyle via risk and physical activity standardized questionnaire. MetS was defined on the basis of the National Cholesterol Education Program Adult Treatment Panel III and the Latin American Diabetes Association criteria. Multiple logistic regression analyses were used to examine whether elevation of residence and health-related lifestyles can increase the risk of MetS.

Results: Residing at low elevation increased prevalence of MetS in men (1.37; 95% CI, 1.05-1.76) and elevated fasting glucose in both men (1.80; 95% CI, 1.32-2.46) and women (1.55; 95% CI, 1.24-1.93) after adjusting for confounders. Additionally, a lack of physical activity was identified as an important factor that raises the risk of increased waist circumference in both men (2.05; 95% CI, 1.22-3.45) and women (1.38; 95% CI, 1.05-1.83) living at low elevation.

Conclusion: Our findings suggest that low elevation of residence and physical inactivity are associated with a higher prevalence of MetS in Ecuadorian adults.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/DMSO.S253099DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7323963PMC
June 2020

Thyroxine-binding globulin, peripheral deiodinase activity, and thyroid autoantibody status in association of phthalates and phenolic compounds with thyroid hormones in adult population.

Environ Int 2020 07 25;140:105783. Epub 2020 May 25.

College of Natural Sciences, Soonchunhyang University, Asan, Republic of Korea. Electronic address:

Exposure to consumer chemicals such as phthalates and phenolic compounds has been associated with thyroid hormone disruption in humans. However, information related to factors that may influence such associations, e.g., transport and activation of the hormones, and autoimmunity status, is limited. In the present study, we employed a subpopulation of adults (n = 1,254) who participated in the Korean National Environmental Health Survey (KoNEHS) 2015-2017, and associated urinary concentrations of major phthalate metabolites, bisphenol A (BPA), and parabens, with thyroid hormone-related measures, including free and total T3 and T4, TSH, thyroxine-binding globulin (TBG), calculated peripheral deiodinase (DIO) activity, and thyroid autoantibodies of thyroperoxidase (TPO) and thyroglobulin (Tg). Phthalate metabolites were negatively associated with total T4 and free T3, and positively associated with total T3. These observations could be explained by TBG levels and calculated peripheral DIO activity that were positively associated with phthalates exposure. In contrast, BPA was positively associated with total T4 and negatively associated with total T3, without any changes in TBG concentration. Serum TPO and Tg antibodies were not associated with urinary phthalate metabolites and BPA. However, thyroid autoantibody status appeared to modulate the association of some phthalates with thyroid hormones. For parabens, little to negligible association was observed. The results of our observation show potential underlying mechanisms of phthalates-induced thyroid hormone disruption, and suggests the importance of consideration of thyroid autoimmunity status in association studies for thyroid disrupting chemicals.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envint.2020.105783DOI Listing
July 2020

MicroRNA expression in response to bisphenol A is associated with high blood pressure.

Environ Int 2020 08 18;141:105791. Epub 2020 May 18.

Department of Preventive Medicine, Seoul National University College of Medicine, Seoul 110-799, Republic of Korea.

Bisphenol A (BPA) is a ubiquitous environmental contaminant that is known to be associated with the risk of arterial hypertension. However, the underlying mechanisms describing how BPA exposure leads to high blood pressure (BP) and the role of epigenetics are still unclear. Therefore, we evaluated associations among BPA exposure, microRNA (miRNA) expression, and BP in a randomized crossover trial with 45 non-smoking females over 60 years of age. The participants visited the study site 3 times and were dose-dependently exposed to BPA. Two hours after exposure to BPA, urine and whole blood were collected for BPA measurement and miRNA profiling, and BP was measured. Relationships among urinary BPA level, miRNA expression, and BP were estimated using the mixed effect model. Decreases in miR-30a-5p, miR-580-3p, miR-627-5p, and miR-671-3p and increases in miR-636 and miR-1224-3p attributable to BPA exposure were associated with high BP. The core functional network from BPA exposure to increased BP was found to be on the pathway through these six miRNAs and their predicted BP-related target genes. Our results suggest that epigenetic biomarkers for BPA exposure and hypertension provide mechanistic data to explain hypertension exacerbation as well as key information for predicting the health effects of BPA exposure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envint.2020.105791DOI Listing
August 2020

Effects of the DNA repair inhibitors, cytosine arabinoside and 3-aminobenzamide, on the frequency of radiation-induced micronuclei, nuclear buds, and nucleoplasmic bridges.

Genes Genomics 2020 06 20;42(6):673-680. Epub 2020 Apr 20.

Department of Preventive Medicine, School of Medicine, Jeju National University, Jeju-si, 63243, Jeju Special Self-Governing Province, Korea.

Background: Micronuclei (MN), nuclear bud (NBud), and nucleoplasmic bridge (NPB) are suggested as biomarkers for radiation exposure; however, they have not been extensively studied to understand the underlying mechanisms responsible for their formation.

Objectives: To (1) validate NBud and NPB within the cytokinesis-blocked micronucleus (CBMN) assay as biomarkers for radiation exposure and (2) determine the effects of the DNA repair inhibitors, cytosine arabinoside (Ara C) and 3-aminobenzamide (3-AB) on radiation-induced MN, NBud, and NPB formation.

Methods: Human blood samples were irradiated with 0-3 Gy X-rays and subsequently treated with Ara C and 3-AB. CBMN and chromosome aberration assays were carried out to measure MN, NBud, and NPB and dicentric chromosomes, respectively.

Results: The frequency of radiation-induced MN, NBud, and NPB increased in a dose-dependent manner. The frequency of MN, NBud, and NPB was highly and positively correlated with the dicentric chromosome, a standard biomarker for biodosimetry (r > 0.98, p < 0.0001). Furthermore, Ara C increased the frequency of MN, NBud, and NPB, whereas 3-AB increased the frequency of MN and NPB, but not NBud. Further, the potentiating effect of Ara C on the frequency of MN, NBud, and NPB was greater than that of 3-AB.

Conclusion: Our results validate NBuds and NPBs as independent valuable markers of radiation exposure. Additionally, we suggest that different mechanisms are likely involved in the formation of NBuds and NPBs following X-irradiation; however, additional studies are warranted to better understand the contribution of distinct DNA repair pathways to the formation of radiation-induced damages.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s13258-020-00934-8DOI Listing
June 2020

Parabens in breast milk and possible sources of exposure among lactating women in Korea.

Environ Pollut 2019 Dec 12;255(Pt 2):113142. Epub 2019 Sep 12.

Department of Health, Environment & Safety, Eulji University, Seongnam-si, Gyeonggi-do, 13135, South Korea. Electronic address:

Parabens, broad-spectrum antimicrobial preservatives widely used in various consumer products and food, are suspected to be linked with several adverse health effects in humans, especially newborn babies, infants, and young children. While human exposure to parabens has been frequently reported by measuring the concentration of parabens in urine, similar measurements in breast milk have rarely been made. To determine paraben concentrations in breast milk and possible sources of exposure, four major parabens, including methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butylparaben (BP) were measured in breast milk samples collected from 260 lactating women in South Korea. Demographic, socioeconomic, and behavioral factors associated with the presence of parabens in breast milk were determined. EP concentrations were detected at the highest levels in breast milk samples, followed by MP, PP, and BP. Pre-pregnancy BMI, parity, use of basic skin care products, use of cosmetics, canned beverage, and type of milk consumption were associated with higher frequencies of paraben detection. In addition, type of milk, parity, and drinking status were significantly associated with the concentration of EP. Multiple regression analyses showed that colostrum and transitional milk samples had higher levels of EP than mature milk samples. The estimated daily intake of parabens in infants via breastfeeding appears to be negligible when compared to the acceptable daily intake values set forth by the European Food Safety Authority (EFSA); however, considering the vulnerability of breastfed infants and ubiquitous sources of exposure from daily use of household and personal toiletries, efforts to identify sources and mitigate exposure are warranted.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envpol.2019.113142DOI Listing
December 2019

Reproductive characteristics are associated with gene-specific promoter methylation status in breast cancer.

BMC Cancer 2019 Sep 18;19(1):926. Epub 2019 Sep 18.

Department of Epidemiology, University of North Carolina, Chapel Hill, NC, 27599, USA.

Background: Reproductive characteristics are well-established risk factors for breast cancer, but the underlying mechanisms are not fully resolved. We hypothesized that altered DNA methylation, measured in tumor tissue, could act in concert with reproductive factors to impact breast carcinogenesis.

Methods: Among a population-based sample of women newly diagnosed with first primary breast cancer, reproductive history was assessed using a life-course calendar approach in an interviewer-administered questionnaire. Methylation-specific polymerase chain reaction and Methyl Light assays were used to assess gene promotor methylation status (methylated vs. unmethylated) for 13 breast cancer-related genes in archived breast tumor tissue. We used case-case unconditional logistic regression to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for associations with age at menarche and parity (among 855 women), and age at first birth and lactation (among a subset of 736 parous women) in association with methylation status.

Results: Age at first birth > 27 years, compared with < 23 years, was associated with lower odds of methylation of CDH1 (OR = 0.44, 95% CI = 0.20-0.99) and TWIST1 (OR = 0.48, 95% CI = 0.28-0.82), and higher odds of methylation of BRCA1 (OR = 1.63, 95% CI = 1.14-2.35). Any vs. no lactation was associated with higher odds of methylation of the PGR gene promoter (OR = 1.59, 95% CI = 1.01-2.49). No associations were noted for parity and methylation in any of the genes assayed.

Conclusions: Our findings indicate that age at first birth, lactation and, perhaps age at menarche, are associated with gene promoter methylation in breast cancer, and should be confirmed in larger studies with robust gene coverage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12885-019-6120-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6749688PMC
September 2019

Prediagnosis aspirin use, DNA methylation, and mortality after breast cancer: A population-based study.

Cancer 2019 11 12;125(21):3836-3844. Epub 2019 Aug 12.

Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina.

Background: The authors hypothesized that epigenetic changes may help to clarify the underlying biologic mechanism linking aspirin use to breast cancer prognosis. To the authors' knowledge, this is the first epidemiologic study to examine whether global methylation and/or tumor promoter methylation of breast cancer-related genes interact with aspirin use to impact mortality after breast cancer.

Methods: Prediagnosis aspirin use was assessed through in-person interviews within a population-based cohort of 1508 women diagnosed with a first primary breast cancer in 1996 and 1997. Global methylation in peripheral blood was assessed by long interspersed elements-1 (LINE-1) and the luminometric methylation assay. Promoter methylation of 13 breast cancer-related genes was measured in tumor by methylation-specific polymerase chain reaction and the MethyLight assay. Vital status was determined by the National Death Index through December 31, 2014 (N = 202/476 breast cancer-specific/all-cause deaths identified among 1266 women with any methylation assessment and complete aspirin data). Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% CIs, and the likelihood ratio test was used to evaluate multiplicative interactions.

Results: All-cause mortality was elevated among aspirin users who had methylated promotor of BRCA1 (HR, 1.67; 95% CI, 1.26-2.22), but not among those with unmethylated promoter of BRCA1 (HR, 0.99; 95% CI, 0.67-1.45; P for interaction ≤.05). Decreased breast cancer-specific mortality was observed among aspirin users who had unmethylated promotor of BRCA1 and PR and global hypermethylation of LINE-1 (HR, 0.60, 0.78, and 0.63, respectively; P for interaction ≤.05), although the 95% CIs included the null.

Conclusions: The current study suggests that the LINE-1 global methylation and promoter methylation of BRCA1 and PR in tumor may interact with aspirin use to influence mortality after breast cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/cncr.32364DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7147530PMC
November 2019

Maternal exposures to persistent organic pollutants are associated with DNA methylation of thyroid hormone-related genes in placenta differently by infant sex.

Environ Int 2019 09 1;130:104956. Epub 2019 Jul 1.

Graduate School of Public Health, Seoul National University, Seoul 08826, Republic of Korea. Electronic address:

Exposure to persistent organic pollutants (POPs) during pregnancy is associated with a disruption in thyroid hormone balance. The placenta serves as an important environment for fetal development and also regulates thyroid hormone supply to the fetus. However, epigenetic changes of thyroid regulating genes in placenta have rarely been studied. This study was conducted to evaluate the association between several POP concentrations in maternal serum and DNA methylation of thyroid hormone-related genes in the placenta. The placenta samples were collected from 106 Korean mother at delivery, and the promoter methylation of the placental genes was measured by a bisulfite pyrosequencing. The deiodinase type 3 (DIO3), monocarboxylate transporter 8 (MCT8), and transthyretin (TTR) genes were selected as the target genes as they play an important role in the regulation of fetal thyroid balance. Because people are exposed to multiple chemicals at the same time, a multiple-POP model using principal component analysis (PCA) was applied to evaluate the association between the multiple POPs exposure and the epigenetic change in placenta. In addition, a single-POP model which includes one chemical each in the statistical model for association was conducted. Based on the single-POP models, serum concentrations of p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and brominated diphenyl ether-47 (BDE-47) were significantly associated with an increase in placental DIO3 methylation, but only among female infants. Among male infants, a positive association between serum p,p'-DDT and MCT8 methylation level was found. According to the multiple-POP models, serum DDTs were positively associated with DIO3 methylation in the placenta of female infants, while a positive association with MCT8 methylation was observed in those of the male infants. Our observation showed that in utero exposure to DDTs may influence the DNA methylation of DIO3 and MCT8 genes in the placenta, in a sexually dimorphic manner. These alterations in placental epigenetic regulation may in part explain the thyroid hormone disruption observed among the newborns or infants followed by in utero exposure to POPs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envint.2019.104956DOI Listing
September 2019

Multiwalled Carbon Nanotubes of Varying Size Lead to DNA Methylation Changes That Correspond to Lung Inflammation and Injury in a Mouse Model.

Chem Res Toxicol 2019 08 16;32(8):1545-1553. Epub 2019 Jul 16.

Center for Environmental Health Sciences, Department of Biomedical and Pharmaceutical Sciences , University of Montana , Missoula , Montana 59812 , United States.

Diversity in physicochemical properties of engineered multiwalled carbon nanotubes (MWCNTs) increases the complexity involved in interpreting toxicity studies of these materials. Studies indicate that epigenetic changes could be at least partially involved in MWCNTs-induced pro-inflammatory and fibrotic lung pathology. Therefore, we examined distinct methylation changes in response to MWCNTs of varied sizes to identify potential epigenetic biomarkers of MWCNTs exposure and disease progression. C57BL/6 mice were exposed via oropharyngeal instillation to a single dose (50 μg) to one of three differently sized MWCNTs: "narrow short" (NS), "wide short" (WS), and "narrow long" (NL). Vehicle-treated control mice received dispersion media (DM) only. Whole lung lavage fluid (LLF) and lung tissue were collected 24 h and 7 days postexposure to evaluate pro-inflammatory cytokines, epigenetic, or histological responses at acute and subchronic intervals, respectively. Luminometric methylation assay and pyrosequencing were used to measure global DNA methylation as well as promoter methylation of inflammation and fibrosis-related genes, respectively. Pro-inflammatory cytokines, including IL-1ß, IL-6, and TNF-α, were measured using enzyme-linked immunosorbant assay, while airway thickening and interstitial collagen accumulation were measured in 7-day lung tissue using laser scanning cytometry. Distinct patterns of methylation (i.e., , , and ) among the different sized MWCNTs at 24 h postexposure corresponded to some pro-inflammatory cytokine measurements from whole LLF. Fibrosis-related gene, , was significantly hypermethylated after exposures to WS and NL MWCNTs, while only NL MWCNTs induced significantly lower global DNA methylation. After 7 days, a hierarchy in airway thickness and interstitial collagen deposition was observed: NS < WS < NL. However, only airway thickness was significantly greater in the WS and NL MWCNTs-exposed groups than the DM-exposed group. These data suggest that methylation changes could be involved in the initial immune response of inflammation and tissue remodeling that precedes lung disease in response to different MWCNTs sizes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.chemrestox.9b00075DOI Listing
August 2019

Association of Anticholinergic Use with Incidence of Alzheimer's Disease: Population-based Cohort Study.

Sci Rep 2019 05 1;9(1):6802. Epub 2019 May 1.

Department of Public Health Science, Graduate School of Public Health and Institute of Health and Environment, Seoul National University, 08826, Seoul, Republic of Korea.

Drugs with strong anticholinergic properties are used under a variety of conditions; however, they can cause various adverse effects including a negative impact on cognitive functions, with older adults being more susceptible to these effects. We explored whether the use of anticholinergic agents (ACs) affects the risk of Alzheimer's disease (AD) in terms of incidence by using National Health Insurance Service elderly cohort database (2002-2013). As a result, AD risk was higher in subjects with an increased amount of prescriptions for strong ACs over a long period of time (9-12 years) than that in the least-exposed reference group (0-9 dose/year) [hazard ratio (HR) (95% confidence interval (95% CI)) 0.99 (0.95-1.03), 1.19 (1.12-1.26), 1.39 (1.30-1.50); in the 10-49 doses/year, 50-119 doses/year, and ≥120 doses/year groups]. Hazard ratios were particularly high in the young-old subgroup (60-64 years old in 2002) [HR (95% CI) 1.11 (1.04-1.22), 1.43 (1.25-1.65), 1.83 (1.56-2.14); in the 10-49 doses/year, 50-119 doses/year, and ≥120 doses/year groups]. Use of strong ACs dose-dependently increased the risk of AD in terms of incidence when exposure was followed up for 9 years or more, and the association was greater in the young-old subgroup.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-019-43066-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6494800PMC
May 2019

Age-dependent pulmonary reactivity to house dust mite allergen: a model of adult-onset asthma?

Am J Physiol Lung Cell Mol Physiol 2019 05 6;316(5):L757-L763. Epub 2019 Mar 6.

Center for Health and the Environment, University of California , Davis, California.

Asthma is a heterogeneous disease differentiated by factors like allergen sensitivity, inflammation, sex, and age at onset. The mouse model is widely used to study the early-life development of allergic asthma. However, age-dependent allergen responses later in life remain relatively understudied and lack a widely accepted model. To differentiate age-dependent responses to the ubiquitous house dust mite (HDM), 3- and 9-mo-old female C57BL/6 mice were randomized into two groups each and exposed to HDM or phosphate-buffered saline (control) via intranasal instillation for sensitization and challenge phases. At 24 h after challenge, all mice underwent pulmonary function testing and methacholine challenge. Bronchoalveolar lavage fluid (BALF) was collected for assessment of cell differentials, and right lung lobes were fixed, sectioned, and stained for histopathology and immunohistochemistry. Both age groups demonstrated strong inflammatory/allergic responses to HDM exposure. However, only 9-mo-old HDM-exposed mice demonstrated significant airway hyperresponsiveness compared with age-matched controls. These HDM-exposed mice also had ) statistically significant increases in tissue bronchiolitis, perivasculitis, and BALF neutrophilia relative to their younger counterparts and ) significantly increased extent of immunostaining compared with all other groups. This study presents a potential model for adult-onset asthma, focusing specifically on the atopic, perimenopausal female phenotype. Our findings suggest that lung function declines with age and that the inflammatory profile of this adult subgroup is a mixed, rather than a simple, atopic, Th2 response. This model may enhance our understanding of how age influences the development of asthmic-like symptoms in older subgroups.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1152/ajplung.00468.2018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6589581PMC
May 2019

Reproductive characteristics modify the association between global DNA methylation and breast cancer risk in a population-based sample of women.

PLoS One 2019 14;14(2):e0210884. Epub 2019 Feb 14.

Department of Epidemiology, University of North Carolina, Chapel Hill, NC, United States of America.

DNA methylation has been implicated in breast cancer aetiology, but little is known about whether reproductive history and DNA methylation interact to influence carcinogenesis. This study examined modification of the association between global DNA methylation and breast cancer risk by reproductive characteristics. A population-based case-control study assessed reproductive history in an interviewer-administered questionnaire. Global DNA methylation was measured from white blood cell DNA using luminometric methylation assay (LUMA) and pyrosequencing assay (long interspersed elements-1 (LINE-1). We estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIs) among 1 070 breast cancer cases and 1 110 population-based controls. Effect modification was assessed on additive and multiplicative scales. LUMA methylation was associated with elevated breast cancer risk across all strata (comparing the highest to the lowest quartile), but estimates were higher among women with age at menarche ≤12 years (OR = 2.87, 95%CI = 1.96-4.21) compared to >12 years (OR = 1.66, 95%CI = 1.20-2.29). We observed a 2-fold increase in the LUMA methylation-breast cancer association among women with age at first birth >23 years (OR = 2.62, 95%CI = 1.90-3.62) versus ≤23 years (OR = 1.32, 95% CI = 0.84-2.05). No modification was evident for parity or lactation. Age at menarche and age at first birth may be modifiers of the association between global DNA methylation and breast cancer risk.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0210884PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6375664PMC
October 2019

Distribution of fipronil in humans, and adverse health outcomes of in utero fipronil sulfone exposure in newborns.

Int J Hyg Environ Health 2019 04 2;222(3):524-532. Epub 2019 Feb 2.

Department of Biomedical and Pharmaceutical Sciences, The University of Montana, Missoula, MT, 59812, USA. Electronic address:

Fipronil is a highly effective insecticide with extensive usages; however, its distribution and toxic/health effects in the human population after chronic exposure have not yet been clearly identified. Our objectives were to determine the levels of serum fipronil and fipronil sulfone, a primary fipronil metabolite, in a general and sensitive human population using a birth cohort of parent-infant triads in Korea. We further investigated whether in utero exposure to fipronil and fipronil sulfone can affect health outcomes in newborn infants. Blood and umbilical cord blood from 169 participants, 59 mother-neonate pairs and 51 matching biological fathers, were collected; serum fipronil and fipronil sulfone (both blood and cord blood) and serum thyroid hormones (cord blood) were measured. Demographic, physiological, behavioral, clinical, and socioeconomic data for each participant were collected via a one-on-one interview and a questionnaire survey. Fipronil sulfone was detected in the serum of mothers, fathers, and infantile cord blood, while fipronil itself was not. Maternal fipronil sulfone levels were correlated to those of matched biological fathers and newborn infants. Adjusted analyses identified significant associations between parental fipronil sulfone levels and household income. Infantile fipronil sulfone levels were significantly associated with both maternal and paternal levels as well as maternal pre-pregnant BMI. Furthermore, infantile fipronil sulfone levels were inversely associated with cord blood T3 and free T3 levels as well as 5-min Apgar scores of newborn infants. Serum fipronil sulfone was detected in a specific population of mother-neonate pairs and their matched biological fathers in a manner suggestive of regular exposure to fipronil among urban residents. The findings also suggest that serum fipronil sulfone placentally transfers to the fetus and affects infantile adverse health outcomes. This is a first of its kind study; therefore, future studies are warranted.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijheh.2019.01.009DOI Listing
April 2019

LINE-1 hypomethylation is associated with radiation-induced genomic instability in industrial radiographers.

Environ Mol Mutagen 2019 03 29;60(2):174-184. Epub 2018 Nov 29.

School of Public Health, Seoul National University, Seoul, South Korea.

Global DNA hypomethylation is proposed as a potential biomarker for cancer risk associated with genomic instability, which is an important factor in radiation-induced cancer. However, the associations among radiation exposure, changes in DNA methylation, and carcinogenesis are unclear. The aims of this study were (1) to examine whether low-level occupational radiation exposure induces genomic DNA hypomethylation; and (2) to determine the relationships between radiation exposure, genomic DNA hypomethylation and radiation-induced genomic instability (RIGI) in industrial radiographers. Genomic DNA methylation levels were measured in blood DNA from 40 radiographers and 28 controls using the LINE-1 pyrosequencing assay and the luminometric methylation assay. Further, the micronucleus-centromere assay was performed to measure aneuploidy of chromosomes 1 and 4 as a marker of delayed RIGI. Genomic DNA methylation levels were significantly lower in radiographers than those in controls. LINE-1 hypomethylation was not significantly correlated with recent 1-year, recent 3-year, or total cumulative radiation doses in radiographers; however, LINE-1 hypomethylation significantly correlated with the cumulative radiation dose without recent 3-year exposure data (D3dose, r = -0.39, P < 0.05). In addition, LINE-1 hypomethylation was a significant contributor to aneuploidy frequency by D3dose (F (2, 34) = 13.85, P < 0.001), in which a total of 45% of the variance in aneuploidy frequency was explained. Our results provide suggestive evidence regarding the delayed effects of low-dose occupational radiation exposure in radiographers and its association with LINE-1 hypomethylation; however, additional studies using more subjects are needed to fully understand the relationship between genomic DNA hypomethylation and RIGI. Environ. Mol. Mutagen. 60: 174-184, 2019. © 2018 Wiley Periodicals, Inc.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/em.22237DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6363886PMC
March 2019

Olfactory Receptor OR51E1 Mediates GLP-1 Secretion in Human and Rodent Enteroendocrine L Cells.

J Endocr Soc 2018 Nov 11;2(11):1251-1258. Epub 2018 Oct 11.

Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, Republic of Korea.

Glucagon-like peptide-1 (GLP-1) and peptide YY (PYY), produced by intestinal enteroendocrine L cells, are important gut hormones that coordinate gastrointestinal physiology, metabolism, and appetite. We aimed to investigate the role of olfactory receptor (OR) OR51E1 in GLP-1 and PYY secretion. We analyzed the expression of olfactory marker protein (OMP), an indicator of OR-mediated events in nonolfactory systems, in human intestinal L cells. Furthermore, we analyzed OMP and OR51E1 expression in the L cell line NCI-H716. To investigate whether odorant-activated OR signaling stimulates GLP-1 and PYY secretion, we used nonanoic acid, a known OR51E1 ligand. Treatment with 100 μM nonanoic acid increased GLP-1 secretion by 2.32 ± 0.41-fold and PYY secretion by 1.44 ± 0.10-fold; however, this effect was attenuated on small interfering RNA-mediated knockdown. Oral administration of nonanoic acid to rats resulted in a 2.89 ± 0.53-fold increase in GLP-1 levels and reductions in blood glucose levels compared with the control group. Nonanoic acid stimulates GLP-1 and PYY secretion via OR51E1 signaling in L cells, thereby indicating a potential role of OR-mediated events in GLP-1 and PYY secretion; this could be translated into a therapeutic approach in treating diabetes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1210/js.2018-00165DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6215084PMC
November 2018

Role of social normative beliefs as a moderating factor in smoking intention among adolescent girls in Korea.

Nurs Health Sci 2018 Dec 12;20(4):530-536. Epub 2018 Sep 12.

College of Nursing, Dankook University, Cheonan, South Korea.

In this study, we investigated the relationship between risk-taking tendency and smoking intention as moderated by social normative beliefs among Korean female adolescents. A cross-sectional study was conducted with 274 female adolescents in middle school. Multiple regression and simple slope analyses were employed to test the moderating effects of social normative beliefs regarding smoking on the relationship between risk-taking tendency and smoking intention. Results determined that risk-taking tendency, social normative beliefs regarding smoking, and their interaction were significant factors influencing smoking intention among adolescents. Risk-taking tendency was associated with greater smoking intention among adolescents, with higher than average social normative beliefs regarding smoking. However, risk-taking tendency was not significantly associated with smoking intention for adolescents with lower than average social normative beliefs regarding smoking. In conclusion, social normative beliefs regarding smoking moderated the relationship between risk-taking intention and smoking intention among Korean female adolescents. Unique sociocultural perceptions about smoking behaviors of adolescents need to be reflected in smoking-prevention and -cessation programs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/nhs.12565DOI Listing
December 2018

Prenatal exposure to persistent organic pollutants and methylation of LINE-1 and imprinted genes in placenta: A CHECK cohort study.

Environ Int 2018 10 10;119:398-406. Epub 2018 Jul 10.

School of Public Health, Seoul National University, Seoul 08826, Republic of Korea. Electronic address:

Prenatal exposure to persistent organic pollutants (POPs) has been linked to numerous adverse birth outcomes among newborn infants in many epidemiological studies. Although epigenetic modifications have been suggested as possible explanations for those associations, studies have rarely reported a relationship between POP exposure during pregnancy and DNA methylation in the placenta. In the present study, we investigated the association between prenatal exposure to several POPs, including organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs), and methylation levels of long interspersed element 1 (LINE-1), as well as imprinted genes in placental DNAs among Korean mother-child pairs (N = 109). We assessed the association of DNA methylation not only with each target POP (single-POP models) but also with multiple POPs applying principal component analysis (multiple-POP models). Potential associations between placental DNA methylation and birth outcomes of newborn infants were also estimated. In single-POP models, significant associations were detected between OCP measurements and placental DNA methylation. Elevated concentrations of β-hexachlorhexane (β-HCH) in maternal serum collected during delivery were significantly associated with a decrease in methylation of LINE-1 in the placenta. Higher levels of p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT) in maternal serum were associated with hypermethylation of insulin-like growth factor 2 (IGF2). In multiple-POP models, a significant and positive association between DDTs and IGF2 methylation was also observed. Placental LINE-1 methylation was inversely associated with birth length. Our observations indicate that prenatal exposure to several POPs including DDTs is associated with the changes in methylation of genes, including major imprinted genes in the placenta. The consequences of these epigenetic alterations in placenta during development deserve further investigation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envint.2018.06.039DOI Listing
October 2018

Olfactory marker protein regulates prolactin secretion and production by modulating Ca and TRH signaling in lactotrophs.

Exp Mol Med 2018 04 6;50(4):1-11. Epub 2018 Apr 6.

Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, Korea.

Olfactory marker protein (OMP) is a marker of olfactory receptor-mediated chemoreception, even outside the olfactory system. Here, we report that OMP expression in the pituitary gland plays a role in basal and thyrotropin-releasing hormone (TRH)-induced prolactin (PRL) production and secretion. We found that OMP was expressed in human and rodent pituitary glands, especially in PRL-secreting lactotrophs. OMP knockdown in GH4 rat pituitary cells increased PRL production and secretion via extracellular signal-regulated kinase (ERK)1/2 signaling. Real-time PCR analysis and the Ca influx assay revealed that OMP was critical for TRH-induced PRL secretion. OMP-knockout mice showed lower fertility than control mice, which was associated with increased basal PRL production via activation of ERK1/2 signaling and reduced TRH-induced PRL secretion. However, both in vitro and in vivo results indicated that OMP was only required for hormone production and secretion because ERK1/2 activation failed to stimulate cell proliferation. Additionally, patients with prolactinoma lacked OMP expression in tumor tissues with hyperactivated ERK1/2 signaling. These findings indicate that OMP plays a role in PRL production and secretion in lactotrophs through the modulation of Ca and TRH signaling.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s12276-018-0035-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5938008PMC
April 2018
-->