The aryl hydrocarbon receptor (AhR) activation mediates benzo(a)pyrene-induced overexpression of AQP3 and Notch1 in HaCaT cells

The aim of this study was twofold: (1) evaluate the effect of benzo[a]pyrene (BaP) on expression levels of AQP3 and Notch1 genes in HaCaT cells exposed "in vitro" and (2) investigate the possible biological role of assessed genes by bioinformatics methods. Cells were exposed to increasing concentrations of BaP (0.0-4.0 μM) for 1-4 days. After treatments, cell viability and expression levels of AhR, CYP1A1, AQP3, and Notch1 genes were evaluated. The possible biological role of assessed genes was evaluated using bioinformatics tools. Low cytotoxicity in HaCaT cells dosed with BaP was detected. A significant overexpression (p < .05) of CYP1A1, AQP3, and Notch1 was found in exposed HaCaT cells. The gene expression upregulation was dependent on AhR activation. The bioinformatics analysis showed that these genes were enriched in related cancer signaling pathways. The findings suggest that AQP3 and Notch1 are upregulated by AhR activation in HaCaT cells exposed to BaP.

Lead (Pb) exposure is associated with changes in the expression levels of circulating miRNAS (miR-155, miR-126) in Mexican women

The environmental contamination with lead (Pb) is considered a critical issue worldwide. Therefore, this study aimed to evaluate the expression levels of circulating miRNAs (miR-155, miR-126, and miR-145) in Mexican women exposed to Pb. Blood lead levels (BLL) were assessed in enrolled women (n = 190) using an atomic absorption method. Also, serum miRNAs expression levels were quantified through a real-time PCR assay. A mean BLL of 10.5 ± 4.50 μg/dL was detected. Overexpression of miR-155 was detected in highly exposed women. Besides, a significant simple positive relationship (p < 0.05) was found between BLL and serum miR-155 expression levels. Additionally, a significant inverse correlation (p < 0.05) was determined between BLL and serum miR-126 expression levels, as downregulation of miR-126 expression levels was observed in highly exposed women. The findings in this study are the concern, as epigenetic changes detected may represent a connection between health illnesses and Pb exposure.

Effect of gene-environment interaction (arsenic exposure - PON1 Q192R polymorphism) on cardiovascular disease biomarkers in Mexican population

Cardiovascular diseases (CVDs) are the primary cause of death worldwide. However, little is known about how the interaction between risk factors affects CVDs. Therefore, the aim of this study was to evaluate the effect of the gene-environment interaction (arsenic exposure x PON1 Q192R polymorphism) on serum levels of CVDs biomarkers in Mexican women. Urinary arsenic levels (UAs) ranged from 5.50-145 μg/g creatinine. The allele frequency was 0.38 and 0.62 for the Q and R alleles, respectively. Moreover, significant associations (p<0.05) were detected between UAs and CVDs biomarkers (ADMA, FABP4, and miR-155). Comparable data were found when CVDs biomarkers were evaluated through PON1 genotype, significant (p<0.05) higher serum concentrations of CVDs biomarkers were identified in R allele carriers compared to levels found in Q allele carriers. Besides, a gene-environment interaction was documented. The results of this study we believe should be of significant interest to regulatory authorities worldwide.

Probabilistic human health risk assessment associated with fluoride and arsenic co-occurrence in drinking water from the metropolitan area of San Luis Potosí, Mexico

A major public health concern in Mexico is the natural contamination of groundwater with fluoride and arsenic. Therefore, this work aimed to evaluate the magnitude of human health risk after determining fluoride and arsenic concentrations in groundwater samples (n = 50) from the Metropolitan area of the city of San Luis Potosi, Mexico. Fluoride levels in water were determined via a potentiometric method using an ion-selective electrode. Arsenic concentrations in water samples were determined with an Atomic Absorption technique. Subsequently, a probabilistic health risk assessment was developed (Monte Carlo Analysis). Fluoride levels in water ranged from 0.20 to 3.50 mg/L. For arsenic, the mean level found in the assessed water samples was 15.5 ± 5.50 μg/L (range: 2.50-30.0 μg/L). In addition, when the probabilistic health risk assessment was completed, a mean HI (cumulative hazardous index) of higher than 1 was detected, indicating a high NCR (non-carcinogenic risk) for children and adults. According to the results found in this study, exposure protection campaigns are imperative in the Metropolitan area of the city of San Luis Potosí, Mexico, to successfully diminish exposure to arsenic and fluoride and, as a consequence, decrease the NCR in the population living in that region of Mexico.

Expression levels of circulating microRNAs-126, -155, and -145 in Mexican women exposed to polycyclic aromatic hydrocarbons through biomass fuel use

Human exposure to polycyclic aromatic hydrocarbons (PAHs) has been considered a risk determinant for the development of cardiovascular diseases (CVD). Therefore, the aim of this study was to assess expression levels of vascular-related miRNAs, miR-126, miR-155, and miR-145, in plasma from women (aged 19-81 years) exposed (n = 100) and non-exposed (n = 20) to PAHs via biomass combustion smoke.1-hydroxypyrene (1-OHP) was determined in urine as a biomarker of exposure to PAHs using high-resolution liquid chromatography. Plasma expression levels of proposed miRNAs were determined by quantitative real-time PCR. Additionally, traditional risk factors (age, blood pressure, serum lipid profile, blood glucose, and among others) associated with CVD were evaluated. Urinary 1-OHP concentrations and plasma expression levels of miR-126 and miR-155 were significantly higher (P < 0.05) in women using wood as a fuel source in their homes (indoor) compared to women from the reference group (non-exposed to biomass smoke). Besides, multivariate linear regression analyses revealed that miR-126[β = 0.61; 95% confidence interval (0.32-0.90)] and miR-155 [β = 0.45; 95% confidence interval (0.13-0.84)] expression levels were significantly associated with urinary 1-OHP concentrations after being adjusted by traditional risk factors (P < 0.05). In contrast, no significant relationship was found between miR-145 and urinary 1-OHP levels. Furthermore, miRNAs assessed in this investigation are associated with CVD events. Consequently, actions to reduce exposure to PAHs in the evaluated population are warranted. Environ. Mol. Mutagen. 60:546-558, 2019. © 2019 Wiley Periodicals, Inc.

Urinary levels of 1-hydroxypyrene and health risk assessment in children living in Mexican communities with a high risk of contamination by polycyclic aromatic hydrocarbons (PAHs)

Health complications have been associated with polycyclic aromatic hydrocarbons (PAHs) exposure, a widespread environmental pollutants family. Therefore, the objective of this investigation was to develop a probabilistic health risk evaluation (using Monte-Carlo simulation) in an infantile population living in areas with a high risk of pollution by PAHs (indoor wood combustion, brick kiln industry, municipal landfill, and low and high vehicular traffic) in Mexico. Urine samples were obtained from Mexican children (n = 135) and urinary 1-OHP concentrations (used as a PAHs biomarker) were quantified. Highest urinary 1-OHP concentrations were detected in children living in areas that use wood combustion as the principal indoor fuel (3.50 ± 0.95 µg/L). Nevertheless, estimated hazard quotients (HQ) lower than 1 were found in all assessed sites after Monte-Carlo analysis. Although HQ <1.0 (a toxic effect is not expected), more data are necessary to determine the real impact of PAHs exposure on children health status.

Circulating miRNA-126, -145 and -155 levels in Mexican women exposed to inorganic arsenic via drinking water

The aim of this research was to investigate circulating expression levels of three miRNAs (miR-126, miR-155, and miR-145) proposed as predictive CVD biomarkers in Mexican women exposed to inorganic arsenic via drinking water. Mean UAs concentration of 19.5 ± 14.0 μg/g creatinine was found after urine samples were analyzed (n = 105). Significant associations between UAs levels and serum expression levels of miR-155 (p < 0.05) and miR-126 (p < 0.05) were observed after adjustment for assessed co-variables. Alterations in the serum expression levels of miR-155 and miR-126 may be associated with the onset and development of cardiovascular diseases, hence miRNAs could be proposed as prognostic CVD biomarkers. Data found in this study are of concern and risk reduction plans are necessary for the assessed communities to prevent cardiovascular events in this population of women.

Impact of arsenic exposure on clinical biomarkers indicative of cardiovascular disease risk in Mexican women

An appropriate and precise identification of high-risk individuals to develop cardiovascular diseases (CVD) is of high importance to reduce these kinds of diseases, a major health concern worldwide. Therefore, the aim of this research was to evaluate prognostic CVD biomarkers in Mexican women exposed to inorganic arsenic via drinking water. Then, a cross-sectional study including 190 women was achieved. Urinary arsenic (UAs) levels were analyzed as exposure biomarker to that metalloid. While, plasma asymmetric dimethylarginine (ADMA), adipocyte fatty acid-binding protein (FABP4), adiponectin, and chemerin levels, hypertriglyceridemic waist (HW) phenotype, atherogenic index of plasma (AIP), and Framingham risk score (FRS) were assessed as prognostic CVD biomarkers. Mean UAs level detected in the evaluated urinary samples was 45.0 ± 40.0 μg/g creatinine. In addition, mean plasma ADMA, FABP4, chemerin and adiponectin levels were 0.68 µmol/L, 20.3 ng/mL, 12.5 μg/mL, and 255 ng/mL, correspondingly. Approximately, 54% of women participants displayed an HW phenotype. Regarding AIP and FRS values, 0.12 ± 0.15 and 7.50 ± 8.00 were found, respectively. Besides, strong and significant associations (p < 0.05) between UAs and AIP, ADMA, and FABP4 were distinguished. Also, after a multivariate analysis, the association between those variables persisted after adjustment for traditional risk factors of CVD. In conclusion, according to the results found in this research, the most sensible CVD biomarkers distinguished in this study were AIP, ADMA, and FABP4. Nevertheless, more studies are necessary to confirm the results found in this investigation.

Exposure to biomass smoke is associated with an increased expression of circulating miRNA-126 and miRNA-155 in Mexican women: a pilot study

Household air pollution has been associated as a risk factor for cardiovascular diseases (CVD). Therefore, the aim of this study was to assess the expression of vascular inflammation regulators miR-126 and miR-155 in plasma from women that cook with wood and women that cook with liquid petroleum gas (LPG). A cumulative index of exposure to smoke (CIES) was estimated, urinary 1-hydroxypyrene (1-OHP) levels were quantified and miRNAs expression levels were determined by quantitative real-time PCR (qRT-PCR). Biochemical clinical parameters were also evaluated. The average values for CIES and 1-OHP were 140 ± 86.8 hours-years (12.0-270 hours-years) and 0.52 ± 0.45 µmol/mol creatinine, respectively. miR-126 and miR-155 expression levels were significantly higher (p < 0.01) in the wood users compared to LPG users. Besides, we found a significant association (p < 0.01) between miR-126 and miR-155 expression levels and CIES and urinary 1-OHP concentrations. These results contribute to the current evidence about the cardiovascular risk related to biomass smoke exposure, from an epigenetic level.

Polybrominated diphenyl ethers (PBDEs) levels in blood samples from children living in the metropolitan area of Guadalajara, Jalisco, Mexico

The aim of this study was to perform a polybrominated diphenyl ethers (PBDEs) exposure assessment using blood samples collected from children living in the metropolitan area of Guadalajara, Jalisco, Mexico (GDL). Five congeners of PBDEs were analyzed using a gas chromatography/mass spectrometry technique. The blood concentrations of total PBDEs ranged from 5.50 to 169 ng/g lipid (42.0 ± 18.0 ng/g lipid; mean ± standard deviation). Regarding BDE congeners, the main congener (highest blood levels) was BDE99 (14.5 ± 5.50 ng/g lipid), followed by BDE100 (9.80 ± 3.40 ng/g lipid) and BDE154 (9.80 ± 5.90 ng/g lipid), and finally BDE153 (5.80 ± 2.30 ng/g lipid) and BDE47 (2.20 ± 1.20 ng/g lipid). In conclusion, blood PBDEs concentrations of concern were detected in this study, as blood levels were similar to the ones found in North America (the highest worldwide).

Serum Concentrations of New Predictive Cardiovascular Disease Biomarkers in Mexican Women Exposed to Lead

The purpose of this study was to evaluate lead exposure and its relationship with serum levels of predictive CVD biomarkers [asymmetric dimethylarginine (ADMA), adipocyte fatty acid-binding protein (FABP4), adiponectin, and chemerin] in women living in San Luis Potosi, Mexico. A mean blood lead level (BLL) of 11.5 ± 9.00 μg/dL (mean ± standard deviation) was found after all blood samples were analyzed. Regarding serum predictive CVD biomarkers, mean serum level of 0.68 ± 0.38 μmol/L, 20.5 ± 16.5 ng/mL, 12.5 ± 3.30 μg/mL, and 255 ± 130 ng/mL were found for ADMA, FABP4, adiponectin, and chemerin, respectively. Simple significant associations (Pearson´s correlations) between BLL and ADMA (r = 0.17; p = 0.04) and FABP4 (r = 0.23; p = 0.03) were found. Furthermore, a multivariate linear regression model showed that BLL was a significant predictor of serum ADMA (β = 0.06; p = 0.001) and FABP4 (β = 1.75; p = 0.0004) concentrations after adjusting by confounders. For serum chemerin and adiponectin levels, no associations were found with BLL. In conclusion, high serum ADMA and FABP4 (predictive CVD biomarkers) levels were found in women exposed to lead. Consequently, this research can be used as a point of departure for the prevention of CVD events in populations living in sites environmentally impacted with lead.

Evaluation of epigenetic alterations (mir-126 and mir-155 expression levels) in Mexican children exposed to inorganic arsenic via drinking water

Recently, a great number of epidemiological studies have shown evidence that exposure to inorganic arsenic could have harmful effects on the cardiovascular system of humans. However, the underlying mechanisms through which arsenic induces cardiovascular toxic effects remain unclear. In this regard, epigenetic mechanisms have emerged as a probable connection between environment and disease phenotypes, including cardiovascular diseases. Therefore, this study aimed to evaluate epigenetic changes related to cardiotoxicity (miR-126 and miR-155 expression levels) in children from San Luis Potosi, Mexico exposed to inorganic arsenic. From 2014 to 2015, in a cross-sectional study, children (aged 6-12 years; n = 73) attending public schools at the studied sites were enrolled to take part in this study. Urinary arsenic was used as an exposure biomarker and analyzed by an atomic absorption spectrophotometry technique. On the other hand, miR-126 and miR-155 expression levels were evaluated by qRT-PCR. A mean urinary arsenic level of 30.5 ± 25.5 μg/g of creatinine was found. Moreover, the data showed a significant negative association (p < 0.05) between urinary arsenic concentrations and plasma miR-126 levels. However, an association between urinary arsenic concentrations and plasma miR-155 levels was not found (p > 0.05). In this regard, some investigations have shown an association between diminished plasma miR-126 levels and cardiovascular illnesses. The results found in this study are of concern. However, more similar studies including a larger sample size are necessary in order to clarify the real significance of the data.

Influence on serum asymmetric dimethylarginine (ADMA) concentrations of human paraoxonase 1 polymorphism (Q192R) and exposure to polycyclic aromatic hydrocarbons (PAHs) in Mexican women, a gene-environment interaction

It has been demonstrated that Cardiovascular Diseases (CVD) are a consequence of the combination of genetic and environmental factors and/or the interaction between them. Therefore, the aim of this study was to evaluate the impact of polycyclic aromatic hydrocarbon (PAHs) exposure and PON1 Q192R polymorphism (genetic susceptibility) on serum asymmetric dimethylarginine (ADMA) levels in Mexican women (n = 206). Urinary 1-hydroxypyrene concentrations (1-OHP; exposure biomarker for PAHs) were quantified using a high-performance liquid chromatography technique, PON1 Q192R polymorphism was genotyped using TaqMan probes and serum ADMA concentrations were evaluated using a commercially available ELISA kit. Urinary 1-OHP levels detected in this study ranged from 0.07 to 9.37 μmol/mol of creatinine (0.13-18.0 μg/g of creatinine). Regarding allele frequency (PON1 Q192R polymorphism), the 192Q-allele frequency was 0.43 and for the 192R-allele it was 0.57. In relation to serum ADMA levels, the levels ranged from 0.06 to 1.46 μmol/L. Moreover, multiple linear regression analysis was performed and associations between urinary 1-OHP levels (β = 0.05, p = 0.002), PON1 Q192R polymorphism (β = 0.04, p = 0.003) and serum ADMA concentrations were found. Besides, an interaction (gene-environment interaction) of both independent variables (1-OHP and PON1 polymorphism) on serum ADMA levels was found (β = 0.04, p = 0.02) in the constructed multiple linear model. Therefore, according to the significance of this research, it is necessary to execute health programs to reduce cardiovascular risk in the assessed population.

Serum adipocyte-fatty acid binding protein (FABP4) levels in women from Mexico exposed to polycyclic aromatic hydrocarbons (PAHs)

Recent studies indicate that exposure to polycyclic aromatic hydrocarbons (PAHs) is a very important risk factor for the development of cardiovascular diseases (CVDs). Correspondingly, adipocyte-fatty acid binding protein (FABP4, also known as aP2 and AFABP) has been proposed as a new, meaningful and useful biomarker to predict metabolic and cardiovascular diseases. Therefore, the aim of this study was to evaluate serum FABP4 levels in Mexican women exposed to PAHs. Urinary 1-hydroxypyrene ((1-OHP), exposure biomarker for PAHs) levels were quantified using a high-performance liquid chromatography (HPLC) technique, and serum FABP4 concentrations were analyzed using a commercially available ELISA kit. The mean urinary 1-OHP level found in women participating in this study was 1.30 ± 1.10 μmol/mol creatinine (2.45 ± 2.10 μg/g creatinine). Regarding serum FABP4 concentrations, the levels ranged from 3.80 to 62.5 ng/mL in the assessed population. Moreover, a significant association (p < 0.001) was found between urinary 1-OHP levels and serum FABP4 concentrations in women after adjusting for potential confounding variables. The presented data in this study can be considered only as a starting point for further studies. Then, in order to elucidate whether FABP4 represents a risk factor for CVD disease in humans exposed to air contaminants (such as PAHs), large epidemiological studies are necessary.

Urinary 1-hydroxypyrene concentration as an exposure biomarker to polycyclic aromatic hydrocarbons (PAHs) in Mexican women from different hot spot scenarios and health risk assessment

Recently, in developing countries, polycyclic aromatic hydrocarbons (PAHs) have been considered contaminants of grave concern for women and children. Therefore, the aim of this study was twofold: (1) evaluate exposure assessment to PAHs using urinary 1-hydroxypyrene (1-OHP) as an exposure biomarker and (2) perform a health risk assessment in women from four different high risk scenarios in Mexico. From 2012 to 2013, in a cross-sectional study, we evaluated a total of 184 healthy women from the following scenarios: (A) indoor biomass combustion site (n = 50); (B) brick manufacturing site using different materials such as fuel sources (n = 70); (C) industrial site (n = 44); and (D) high vehicular traffic site (n = 20). 1-hydroxypyrene (1-OHP) was quantified using a high-performance liquid chromatography (HPLC) technique. Afterward, a probabilistic health risk assessment was performed (Monte Carlo analysis). Mean urinary 1-OHP levels found were 0.92 ± 0.92; 0.91 ± 0.83; 0.22 ± 0.19; and 0.14 ± 0.17 μg/L for scenario A, B, C, and D, respectively. Then, based on the measured urinary 1-OHP levels, the estimated median daily intake doses of pyrene were calculated: 659, 623, 162, and 77.4 ng/kg/day for the women participating in the study living in areas A, B, C, and D, respectively, and finally, the hazard quotient (HQ) was calculated (22 ± 21, 21 ± 20, 5.5 ± 5.5, and 2.6 ± 3.5; for areas A, B, C, and D, respectively), high health risk was noted for the women living in the studied communities. The data shown in this study (exposure levels to PAHs and health risk assessment) made it reasonable to conclude that the exposure levels found have a significant potential for generating adverse effects on human health in the studied scenarios.

Polybrominated diphenyl ethers (PBDEs) concentration in soil from San Luis Potosi, Mexico: levels and ecological and human health risk characterization

The aim of this study was to assess the levels of polybrominated diphenyl ethers (PBDEs) in soils from the city of San Luis Potosi in Mexico and perform an ecological and human health risk characterization. In order to confirm the presence of PBDEs, outdoor surface soil samples were collected and the concentrations of PBDEs in urban, industrial, agricultural, and brick kiln industry areas were determined. The mean total PBDEs levels obtained in the study sites were 25.0 ± 39.5 μg/kg (geometric mean ± standard deviation) in the brick kiln industry zone; 34.5 ± 36.0 μg/kg in the urban zone; 8.00 ± 7.10 μg/kg in the industrial zone and 16.6 ± 15.3 μg/kg in the agricultural zone. The ecological and human health risk characterization showed relatively low-hazard quotient values. However, the moderately high PBDEs levels found in soils highlight the necessity to establish a systematic monitoring process for PBDEs in environmental and biological samples.

Assessment of vascular function in Mexican women exposed to polycyclic aromatic hydrocarbons from wood smoke

The use of solid fuels for cooking and heating is likely to be the largest source of indoor air pollution on a global scale; these fuels emit substantial amounts of toxic pollutants such as polycyclic aromatic hydrocarbons (PAHs) when used in simple cooking stoves (such as open "three-stone" fires). Moreover, indoor air pollution from biomass fuels is considered an important risk factor for human health. The aim of this study was to evaluate the relationship between exposure to PAHs from wood smoke and vascular dysfunction; in a group of Mexican women that use biomass combustion as their main energy source inside their homes. We used 1-hydroxypyrene (1-OHP) as an exposure biomarker to PAHs and it was assessed using high performance liquid chromatography. The endothelium-dependent vasodilation was assessed through a vascular reactivity compression test performed with a pneumatic cuff under visualization of the brachial artery using high resolution ultrasonography (HRU). Assessment of the carotid intima-media thickness (CIMT) was used as an atherosclerosis biomarker (also assessed using HRU); and clinical parameters such as anthropometry, blood pressure, glucose, triglycerides, total cholesterol, HDL cholesterol, LDL cholesterol, among others were also evaluated. The mean concentration of urinary 1-OHP found in exposed women was 0.46±0.32μmol/mol Cr (range: 0.086-1.23μmol/mol Cr). Moreover, vascular dysfunction (diminished endothelium dependent vasodilation) was found in 45% of the women participating in the study. Association between vascular function and 1-OHP levels was found to be significant through a logistic regression analysis (p=0.034; r(2)=0.1329). Furthermore, no association between CIMT and clinical parameters, urinary 1-OHP levels or vascular dysfunction was found. Therefore, with the information obtained in this study, we advocate for the need to implement programs to reduce the risk of exposure to PAHs in communities that use biomass fuels as a main energy source.