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Objective: There is a broad spectrum of dietary supplements (DS) and their accessibility worldwide. However, little is known about the prevalence of DS use among Bangladeshi adolescents. This study estimates the prevalence, correlates and common conditions related to DS use. Design: A cross-sectional, convenient sampling strategy was adopted using an interviewer-administered, structured questionnaire. Setting: Kurigram and Patuakhali districts of Bangladesh. Participants: 702 adolescents aged 10–19 years. Results: The overall prevalence of DS use was 83 %. The majority of participants (93·4 %) agreed that DS were good for health, and 28·3 % reported general health and well-being as the reason for using DS. The most frequently used supplements were multivitamins (38·6 %) and Ca (37 %). DS use was more common among adolescents who had ≤5 siblings, good health status, no chronic diseases, a positive impression that DS are good for health and who had the tendency to encourage DS to others. DS use was also higher among those who received DS information from healthcare providers, professional literature, friends, family and relatives. Conclusions: The prevalence of DS use is relatively higher among Bangladeshi adolescents compared to Bangladeshi adults and adolescents from other countries, highlighting the inclination towards DS use. Guidelines for safe DS use for adolescents are warranted to control DS use and prevent adverse effects.

Background Evidence from pandemic and pre-pandemic studies conducted globally indicates that people with disabilities (PWDs) have a higher risk for suicidality. However, none of these studies has assessed suicidality among PWDs in Bangladesh. Aims The purpose of this study was to determine the prevalence of and factors associated with suicidal ideation among PWDs during the COVID-19 pandemic in Bangladesh. Method Using a snowball sampling technique, a cross-sectional survey was conducted from February to April 2021 among PWDs from six districts in the northern region of Bangladesh. Information related to sociodemographic factors, clinical characteristics, behavioural factors and suicidal ideation was collected. Chi-squared test and logistic regression were used to describe the data and explain the relationship of factors associated with suicidal ideation. Results The prevalence of COVID-19-related past-year suicidal ideation was 23.9%. The factors associated with suicidal ideation included: age above 35 years, being female, acquiring a disability later in life, lack of sleep and current substance use. In addition, higher education appeared to be a protective factor against suicidal ideation. Conclusions This study highlighted that PWDs had an increased risk of suicide; that is, one-fourth of them had past-year suicidal ideation. This may have been because of COVID-19-related restrictions and stressors. Thus, the government and policy makers need to pay more attention to developing effective suicide assessment, treatment and management strategies, especially for at-risk groups, to minimise the impact of the COVID-19 outbreak.

Background We earlier demonstrated that vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) exhibit the overexpression of Giα proteins and hyperproliferation that is attributed to the enhanced levels of endogenous II angiotensin (Ang II). In addition, the implication of Sirtuin1 (Sirt1) a histone deacetylase class III family in Ang II-induced hypertension has also been shown. We recently demonstrated that Ang II increased the expression of Sirt-1 in aortic VSMC that contributed to the overexpression of Giα proteins. However, whether Sirt1 is overexpressed in VSMC from SHR and is linked to the enhanced expression of Giα proteins and hyperproliferation remains unexplored. Method and results In the present study, we show that Sirt1 is upregulated in VSMC from SHR and this upregulation was attenuated by AT1 receptor antagonist losartan. In addition, the inhibition or knockdown of Sirt1 by specific inhibitors EX 527 and NAM and/or siRNA attenuated the enhanced expression of Giα proteins, cell cycle proteins and hyperproliferation of VSMC from SHR. Furthermore, the enhanced levels of reactive oxygen species (ROS), hydrogen peroxide and NADPH oxidase subunits NOX2 and p47phox, increased phosphorylation of EGFR, ERK1/2 and AKT displayed by VSMC from SHR were also attenuated by knocking down of Sirt1 by siRNA. Conclusion In summary, our results demonstrate that Sirt1 is overexpressed in VSMC from SHR which through augmenting oxidative stress contributes to the enhanced expression of Giα proteins, cell cycle proteins and resultant hyperproliferation of VSMC.

We earlier showed that angiotensin (Ang) II-induced overexpression of Giα proteins contributes to the hyperproliferation of vascular smooth muscle cells (VSMC). In addition, the implication of the JAK2/STAT3 pathway in Ang II-induced hyperproliferation of VSMC has also been reported. However, the role of the JAK2/STAT3 pathway in Ang II-induced overexpression of Giα proteins and hyperproliferation of VSMC remains unexplored. In the present study, we show that inhibition or knockdown of the JAK2/STAT3 pathway by a specific inhibitor “cucurbitacin I” (CuI) or siRNAs attenuated Ang II-induced overexpression of Giα proteins and hyperproliferation of VSMC. In addition, the enhanced expression of cell cycle proteins induced by Ang II was also attenuated by CuI. Furthermore, Ang II-induced enhanced production of the superoxide anion (O2 –), H2O2, and NADPH oxidase activity, as well as the enhanced expression of NADPH oxidase subunits implicated in enhanced expression of Giα proteins and hyperproliferation, were also attenuated by inhibition of the JAK2/STAT3 pathway. On the other hand, Ang II-induced inhibition and augmentation of the levels of nitric oxide and peroxynitrite, respectively, in VSMC were restored to control levels by CuI. In summary, our results demonstrate that Ang II through the JAK2/STAT3 pathway increases nitroxidative stress, which contributes to the overexpression of Giα proteins and cell cycle proteins and the hyperproliferation of VSMC.

BackgroundExposure to electronic-cigarette (e-cig) aerosols induces potentially fatal e-cig or vaping-associated lung injury (EVALI). The cellular and molecular mechanisms underlying these effects, however, are unknown. We used an air–liquid interface (ALI) in vitro model to determine the influence of two design characteristics of third-generation tank-style e-cig devices—resistance and voltage—on (1) e-cig aerosol composition and (2) cellular toxicity.MethodsHuman bronchial epithelial cells (H292) were exposed to either butter-flavored or cinnamon-flavored e-cig aerosols at the ALI in a Vitrocell exposure system connected to a third-generation e-cig device. Exposures were conducted following a standard vaping topography profile for 2 h per day, for 1 or 3 consecutive days. 24 h after ALI exposures cellular and molecular outcomes were assessed.ResultsWe found that butter-flavored e-cig aerosol produced under ‘sub-ohm’ conditions ( 1 Ω and voltage > 4.5 V), contains lower carbonyl levels (ConclusionThe production of high levels of carbonyls may be flavor specific. Overall, inhaling e-cig aerosols produced under ‘sub-ohm’ conditions is detrimental to lung epithelial cells, potentially via mechanisms associated with OS. This information could help policymakers take the necessary steps to prevent the manufacturing of sub-ohm atomizers for e-cig devices.

Currently, more than 9 million American adults, including women of childbearing age, use electronic-cigarettes (e-cigs). Further, the prevalence of maternal vaping now approaching 10% is similar to that of maternal smoking. Little, however, is known about the effects of fetal exposures to nicotine-rich e-cig aerosols on lung development. In this study, we assessed whether in utero exposures to e-cig aerosols compromised lung development in mice. A third-generation e-cig device was used to expose pregnant BALB/c mice by inhalation to 36 mg/mL of nicotine cinnamon-flavored e-cig aerosols for 14–31 days. This included exposures for either 12 days before mating plus during gestation (preconception groups) or only during gestation (prenatal groups). Respective control mice were exposed to filtered air. Subgroups of offspring were euthanized at birth or at 4 wk of age. Compared with respective air-exposed controls, both preconception and prenatal exposures to e-cig aerosols significantly decreased the offspring birth weight and body length. In the preconception group, 7 inflammation-related genes were downregulated, including 4 genes common to both dams and fetuses, denoting an e-cig immunosuppressive effect. Lung morphometry assessments of preconception e-cig-exposed offspring showed a significantly increased tissue fraction at birth. This result was supported by the downregulation of 75 lung genes involved in the Wnt signaling, which is essential to lung organogenesis. Thus, our data indicate that maternal vaping impairs pregnancy outcomes, alters fetal lung structure, and dysregulates the Wnt signaling. This study provides experimental evidence for future regulations of e-cig products for pregnant women and developmentally vulnerable populations.

Angiotensin II (ANG II) plays an important role in the regulation of various physiological functions including proliferation, hypertrophy of vascular smooth muscle cells (VSMCs) through the overexpression of Giα proteins. Sirtuin 1 (Sirt1), a class III histone deacetylase and epigenetic regulator is implicated in a wide range of cellular functions, including migration and growth of VSMCs and in ANG II-induced hypertension. The present study was undertaken to examine the role of Sirt1 in ANG II-induced overexpression of Giα proteins and hyperproliferation of aortic VSMCs. We show that ANG II treatment of VSMCs increased the expression of Sirt1, which was attenuated by AT

Background and objectives The COVID-19 pandemic has negatively impacted health systems worldwide, including in Bangladesh, limiting access to family planning information (FP) and services. Unfortunately, the evidence on the factors linked to such disruption is limited, and no study has addressed the link among Bangladeshis. This study aimed to examine the socioeconomic, demographic, and other critical factors linked to the use of FP in the studied areas during the COVID-19 pandemic. Methods The characteristics of the respondents were assessed using a cross-sectional questionnaire survey and descriptive statistics. The variables that were substantially linked with FP usage were identified using a Chi-square test. In addition, a multivariate logistic regression model was used to identify the parameters linked to FP in the study areas during the COVID-19 pandemic. Results The prevalence of FP use among currently married 15–49 years aged women was 36.03% suggesting a 23% (approximately) decrease compared to before pandemic data. Results also showed that 24.42% of the respondents were using oral contraceptive pills (OCP) which is lower than before pandemic data (61.7%). Multivariate regression analysis provided broader insight into the factors affecting FP use. Results showed that woman’s age, education level of the respondents, working status of the household head, locality, reading a newspaper, FP workers’ advice, currently using OCP, ever used OCP, husbands’ supportive attitude towards OCP use, duration of the marriage, ever pregnant, the number of children and dead child were significantly associated with FP use in the study areas during COVID-19 pandemic. Conclusions This study discusses unobserved factors that contributed to a reduction in FP use and identifies impediments to FP use in Bangladesh during the COVID-19 epidemic. This research further adds to our understanding of FP usage by revealing the scope of the COVID-19 pandemic’s impact on FP use in Bangladesh’s rural and urban areas.

Arsenic, a naturally occurring toxic element, and a traditional drug, has received a great deal of attention worldwide because of its curative anticancer properties in patients with acute promyelocytic leukemia. Chronic arsenic exposure is a well-known risk factor for various diseases, including skin diseases, cancers, and cardiovascular disorders, such as atherosclerosis and hypertension. To date, the molecular pathogenesis underlying arsenic-induced diseases is obscure. Arsenic trioxide (ATO) has been used as an antileukemic drug worldwide. Recent advances in cancer therapeutics have led to a paradigm shift away from traditional cytotoxic drugs toward the targeting of proteins closely associated with cancer phenotype. Due to the diverse anticancer effects of ATO on different types of malignant tumors, numerous studies have attempted to uncover the mechanisms of ATO-induced tumor suppression. The outcomes of these studies have opened doors for the potential establishment of improved molecular-targeted therapies for cancer treatment. In this chapter, we discuss the current understanding of arsenic-induced diseases and arsenic-based cancer therapies. We also summarize the novel molecular aspects associated with both arsenic-related toxic and therapeutic effects.

Backgroud JUUL, an electronic nicotine delivery system (ENDS), which first appeared on the US market in 2015, controled more than 75% of the US ENDS sales in 2018. JUUL-type devices are currently the most commonly used form of ENDS among youth in the US. In contrast to free-base nicotine contained in cigarettes and other ENDS, JUUL contains high levels of nicotine salt (35 or 59 mg/mL), whose cellular and molecular effects on lung cells are largely unknown. In the present study, we evaluated the in vitro toxicity of JUUL crème brûlée-flavored aerosols on 2 types of human bronchial epithelial cell lines (BEAS-2B, H292) and a murine macrophage cell line (RAW 264.7). Methods Human lung epithelial cells and murine macrophages were exposed to JUUL crème brûlée-flavored aerosols at the air–liquid interface (ALI) for 1-h followed by a 24-h recovery period. Membrane integrity, cytotoxicity, extracellular release of nitrogen species and reactive oxygen species, cellular morphology and gene expression were assessed. Results Crème brûlée-flavored aerosol contained elevated concentrations of benzoic acid (86.9 μg/puff), a well-established respiratory irritant. In BEAS-2B cells, crème brûlée-flavored aerosol decreased cell viability (≥ 50%) and increased nitric oxide (NO) production (≥ 30%), as well as iNOS gene expression. Crème brûlée-flavored aerosol did not affect the viability of either H292 cells or RAW macrophages, but increased the production of reactive oxygen species (ROS) by ≥ 20% in both cell types. While crème brûlée-flavored aerosol did not alter NO levels in H292 cells, RAW macrophages exposed to crème brûlée-flavored aerosol displayed decreased NO (≥ 50%) and down-regulation of the iNOS gene, possibly due to increased ROS. Additionally, crème brûlée-flavored aerosol dysregulated the expression of several genes related to biotransformation, inflammation and airway remodeling, including CYP1A1, IL-6, and MMP12 in all 3 cell lines. Conclusion Our results indicate that crème brûlée-flavored aerosol causes cell-specific toxicity to lung cells. This study contributes to providing scientific evidence towards regulation of nicotine salt-based products.

Currently, more than 9 million American adults, including women of childbearing age, use electronic-cigarettes (e-cigs). Further, the prevalence of maternal vaping now approaching 10% is similar to that of maternal smoking. Little, however, is known about the effects of fetal exposures to nicotine-rich e-cig aerosols on lung development. In this study, we assessed whether in utero exposures to e-cig aerosols compromised lung development in mice. A third-generation e-cig device was used to expose pregnant BALB/c mice by inhalation to 36 mg/mL of nicotine cinnamon-flavored e-cig aerosols for 14-31 days. This included exposures for either 12 days before mating plus during gestation (preconception groups) or only during gestation (prenatal groups). Respective control mice were exposed to filtered air. Subgroups of offspring were euthanized at birth or at 4 wk of age. Compared with respective air-exposed controls, both preconception and prenatal exposures to e-cig aerosols significantly decreased the offspring birth weight and body length. In the preconception group, 7 inflammation-related genes were downregulated, including 4 genes common to both dams and fetuses, denoting an e-cig immunosuppressive effect. Lung morphometry assessments of preconception e-cig-exposed offspring showed a significantly increased tissue fraction at birth. This result was supported by the downregulation of 75 lung genes involved in the

Additional file 1: Table S1. Primer set sequences used in this study. Figure S1. JUUL crème brûlée-flavored aerosol increases extracellular ROS production in H292 cells (trial #2). Figure S2. JUUL crème brûlée-flavored aerosol increases extracellular ROS production in H292 cells (trial #3). Figure S3. Short-term ALI JUUL aerosol exposure alters extracellular ROS and NO production in RAW 246.7 macrophages (trial #2). Figure S4. Short-term ALI JUUL aerosol exposure alters extracellular ROS and NO production in RAW 246.7 macrophages (trial #3).

We previously showed that augmented levels of endogenous angiotensin II (AngII) contribute to vascular smooth muscle cell (VSMC) hypertrophy through the transactivation of growth factor receptors in spontaneously hypertensive rats. Resveratrol (RV), a polyphenolic component of red wine, has also been shown to attenuate AngII-evoked VSMC hypertrophy; however, the molecular mechanism mediating this response is obscure. The present study was therefore undertaken to examine whether RV could prevent AngII-induced VSMC hypertrophy through the transactivation of growth factor receptor and associated signaling pathways. AngII treatment of VSMC enhanced the protein synthesis that was attenuated towards control levels by RV pretreatment as well as by the inhibitors of NADPH oxidase, c-Src, and growth factor receptors. Furthermore, RV pretreatment also inhibited enhanced levels of superoxide anion, NADPH oxidase activity, increased expression of NADPH oxidase subunits, and phosphorylation of c-Src, EGF-R, PDGE-R, ERK1/2, and AKT1/2. In conclusion, these results indicate that RV attenuates AngII-induced VSMC hypertrophy through the inhibition of enhanced oxidative stress and activation of c-Src, growth factor receptors, and MAPK/AKT signaling. We suggest that RV could be used as a therapeutic agent in the treatment of vascular complications associated with hypertension and hypertrophy.

We recently showed that sodium nitroprusside (SNP), a NO donor, attenuated hypertension in spontaneously hypertensive rats (SHR). Since hypertension is associated with enhanced proliferation and hypertrophy of vascular smooth muscle cells (VSMC), the present study examines whether in vivo treatment of SHR with SNP could also inhibit the augmented proliferation of VSMC and explore the signaling mechanisms. Treatment of 8 week old SHR and Wistar Kyoto rats with SNP twice a week for 2 weeks inhibited the enhanced proliferation of VSMC from SHR, the enhanced expression of angiotensin II type 1 (AT1) receptor, and enhanced activation of c-Src and growth factor receptors and ERK1/2 signaling pathways. In addition, SNP also inhibited the overexpression of cell cycle proteins including cyclins D1, Cdk4, and phosphorylated pRB and restored the downregulated Cdk inhibitors p21Cip1 and p27Kip1 expression towards control levels. Furthermore, SNP-induced inhibition of enhanced levels of the AT1 receptor and enhanced proliferation was reversed by L-NAME, an inhibitor of nitric oxide synthase. These results suggest that the SNP-induced antiproliferative effect may be mediated through the inhibition of enhanced expression of the AT1 receptor, cell cycle proteins and activation of c-Src, growth factor receptors, and MAP kinase signaling.

We previously showed that decreased levels of intracellular nitric oxide (NO) contribute to the hyperproliferation of vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR). The present study investigates if elevation of intracellular levels of NO by in vivo treatment of SHR with NO donor, sodium nitroprusside (SNP) that was shown to attenuate hypertension could attenuate the hyperproliferation of VSMC and identify the molecular mechanisms. Intraperitoneal injection of SNP (0.5 mg/kg BW) into 8-week-old SHR and WKY rats twice a week for two weeks increased significantly the intracellular levels of NO in aortic VSMC and resulted in the attenuation of hyperproliferation of VSMC from SHR to control levels. The antiproliferative effect of SNP was associated with the restoration of the overexpression of cell cycle proteins, cyclins D1, E, Cdk2, Cdk4, phosphorylated pRB and decreased expression of Cdk inhibitors p21Cip1 and p27Kip1 towards control levels. In addition, SNP treatment also attenuated the overexpression of angiotensin II receptor type 1 (AT1) receptor, phosphorylation of c-Src, EGF-R, PDGF-R, IGF-IR and ERK1/2 in VSMC from SHR to control levels. These results suggest that the augmentation of intracellular levels of NO elicits antiproliferative effect that may be mediated through its ability to inhibit the enhanced expression of AT1 receptor, activation of c- Src, growth factor receptors and MAP kinase signaling and overexpression of cell cycle proteins.

Neurofibromatosis type 1 (NF1) is a genetic disorder where affected individuals develop benign or malignant nervous system tumors. To date, NF1 is caused by mutations in the NF1 tumor suppressor gene located at chromosome band 17q11.2. In this study, we aimed to characterize novel recurrent regional chromosomal imbalances and tumor-related candidate genes in NF1-associated cutaneous neurofibromas. Nine cutaneous neurofibromas from NF1 patients were screened for recurrent chromosomal imbalances using high-resolution 400K oligonucleotide array comparative genomic hybridization (aCGH). All the cases exhibited at least one sub-microscopic abnormality. Regions of recurrent chromosomal imbalances in a least one third of cases were loss of 1q13.2 (33%, FAM19A3), 1q21.1 (44%, RABGAP1L), 2q37.1 (56%, INPP5D), 3p25.1 (67%, CHCHD4), 4p15.32 (56%, FGFBP1), 5q11.2 (56%, ARL15), 6q22.31 (56%, NKAIN2), 6q22.33 (67%, ARHGAP18), 6q25.1 (67%, UST), 7q13 (56%, ADCY1), 12q13.13 (44%, KRT71), 19q13.32 (56%, GRLF1), and 20p11.21 (56%, NLP) and gain of 2p23.3 (76%, C2orf53), 8q22.3 (44%, ODF1) and 8q24.3 (67%, ARC). Several chromosomal imbalances, including loss of 7q11.23, 13q14.1, 14q32.13, 17p12, and 17q11.2 were detected at a lower frequency. We also confirmed that these chromosomal imbalances were not detected in the patient-matched lymphocyte DNAs. Amongst the 6 tumor-related candidate genes (RABGAP1L, ADCY1, SLIT2, GRLF1, UST, and ARC) identified in the regions of recurrent chromosomal imbalances, the gene expression changes of UST (down-regulation) and ARC (up-regulation) were found to be significantly associated with copy number alterations. The novel recurrent chromosomal imbalances and the altered expression levels of the tumor-related candidate genes may be associated with the development of NF1-associated benign cutaneous neurofibromas.

Resveratrol, a natural polyphenolic compound has been reported to attenuate angiotensin II -induced vascular smooth muscle cell (VSMC) hypertrophy; however, whether resveratrol could also inhibit hyperproliferation of VSMC from spontaneously hypertensive rats (SHR) is unexplored. The present study investigates the effect of resveratrol on hyperproliferation of VSMC from SHR and the underlying molecular mechanisms responsible for this response. For these studies, aortic VSMC from SHR and Wistar-Kyoto (WKY) rats were used. The proliferation of VSMC was determined by [3H] thymidine incorporation and the levels of proteins were determined by Western blotting. The enhanced proliferation exhibited by VSMC from SHR was attenuated by resveratrol. In addition, resveratrol attenuated the overexpression of cyclin D1, cyclin E, cyclin dependent kinase 4 (Cdk4), Cdk2, phosphorylated retinoblastoma protein (pRb), Giα proteins and enhanced phosphorylation of ERK1/2 and AKT in VSMC from SHR. Furthermore, the overproduction of superoxide anion, increased NADPH oxidase activity, overexpression of Nox2, Nox4 and p47phox proteins, increased phosphorylation of EGFR, IGF-IR, and c-Src were all abrogated by resveratrol. These results suggest that resveratrol attenuates the hyperproliferation of VSMC from SHR through the inhibition of ROS, c-Src, growth factor receptor activation, MAPK/PI3K, Giα and cell cycle proteins that are implicated in VSMC hyperproliferation.

We showed previously that natriuretic peptide receptor-C (NPR-C) agonist, C-ANP4−23, attenuated the enhanced expression of Giα proteins in vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) through the inhibition of enhanced oxidative stress. Since the enhanced levels of endogenous angiotensin II (Ang II) contribute to the overexpression of Giα proteins and augmented oxidative stress in VSMC from SHR, the present study was undertaken to investigate if C-ANP4−23 could also attenuate angiotensin II (Ang II)-induced oxidative stress and associated signaling. Ang II treatment of aortic VSMC augmented the levels of superoxide anion (O2−), NADPH oxidase activity, and the expression of NADPH oxidase subunits and C-ANP4−23 treatment attenuated all these to control levels. In addition, Ang II-induced enhanced levels of thiobarbituric acid-reactive substances (TBARS) and protein carbonyl content were also attenuated toward control levels by C-ANP4−23 treatment. On the other hand, Ang II inhibited the levels of nitric oxide (NO) and augmented the levels of peroxynitrite (OONO−) in VSMC which were restored to control levels by C-ANP4−23 treatment. Furthermore, C-ANP4−23 treatment attenuated Ang II-induced enhanced expression of Giα proteins, phosphorylation of p38, JNK, and ERK 1,2 as well as hyperproliferation of VSMC as determined by DNA synthesis, and metabolic activity. These results indicate that C-ANP4−23, via the activation of NPR-C, attenuates Ang II-induced enhanced nitroxidative stress, overexpression of Giα proteins, increased activation of the p38/JNK/ERK 1,2 signaling pathways, and hyperproliferation of VSMC. It may be suggested that C-ANP4−23 could be used as a therapeutic agent in the treatment of vascular remodeling associated with hypertension and atherosclerosis.

Elevated exposure to arsenic has been suggested to be associated with atherosclerosis leading to cardiovascular disease (CVD). However, biochemical events underlying the arsenic-induced atherosclerosis have not yet been fully documented. The aim of this study was to investigate the associations of circulating molecules involved in atherosclerosis with arsenic exposure in the individuals exposed to arsenic in Bangladesh. A total of 324 study subjects, 218 from arsenic-endemic areas and 106 from nonendemic areas in Bangladesh, were recruited. Drinking water, hair, nail, and blood samples were collected from the study subjects for analysis. Total cholesterol (TC), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) levels were lower in arsenic-endemic subjects than those of nonendemic subjects. Oxidized LDL (Ox-LDL), C-reactive protein (CRP), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) levels were significantly higher in arsenic-endemic subjects than those in nonendemic subjects. All these circulating molecules showed significant correlations with arsenic exposure (water, hair, and nail arsenic concentrations), and all these relations were significant before and after adjusting for relevant covariates. Among the circulating molecules tested in this study, HDL, Ox-LDL, and CRP showed dose-response relationships with arsenic exposure. Ox-LDL/HDL ratios were increased with the increasing concentrations of arsenic in the water, hair, and nails. Furthermore, non-HDL cholesterol and TC/HDL ratios were significantly correlated with arsenic exposure before and after adjusting for relevant covariates. Thus, all the observed associations may be the major features of arsenic exposure-related atherosclerosis leading to CVD.

Arsenic trioxide (ATO) is one of the most potent drugs in cancer chemotherapy, and is highly effective in treating both newly diagnosed and relapse patients with acute promyelocytic leukemia (APL). Despite a number of reports regarding the molecular mechanisms by which ATO promotes anti‐tumor or pro‐apoptotic activity in hematological and other solid malignancies, the effects of ATO on immune responses remain poorly understood. To further understand and clarify the effects of ATO on immune responses, we sought to examine whether ATO affects the production of nitric oxide (NO) in a lipopolysaccharide (LPS)‐stimulated mouse macrophage cell line, RAW 264.7. Arsenic trioxide was found to prevent NO production in a dose‐dependent manner. Arsenic trioxide significantly inhibited the increase in inducible nitric oxide synthase (iNOS) at both the mRNA and protein levels. Furthermore, our analyses revealed that the inhibitory effect of ATO on iNOS expression was ascribed to the prevention of IRF3 phosphorylation, interferon (IFN)‐β expression, and STAT1 phosphorylation, but not the prevention of the MyD88‐dependent pathway. Taken together, our results indicate that ATO prevents NO production by inhibiting the TIR‐domain‐containing adaptor protein inducing IFN‐β (TRIF)‐dependent pathway, thus highlighting an anti‐inflammatory property of ATO in innate immunity.

We earlier showed that vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) exhibit enhanced expression of Giα proteins which was attributed to the decreased levels of nitric oxide (NO), because elevation of the intracellular levels of NO by NO donors; sodium nitroprusside (SNP) and S‐Nitroso‐N‐acetyl‐DL‐penicillamine (SNAP), attenuated the enhanced expression of Giα proteins. Since the enhanced expression of Giα proteins is implicated in the pathogenesis of hypertension, the present study was undertaken to investigate if treatment of SHR with SNP could also attenuate the development of high blood pressure (BP) and explore the underlying molecular mechanisms. Intraperitoneal injection of SNP at a concentration of 0.5 mg/kg body weight twice a week for 2 weeks into SHR attenuated the high blood pressure by about 80 mmHg without affecting the BP in WKY rats. SNP treatment also attenuated the enhanced levels of superoxide anion (O2 −), hydrogen peroxide (H2O2), peroxynitrite (ONOO −), and NADPH oxidase activity in VSMC from SHR to control levels. In addition, the overexpression of different subunits of NADPH oxidase; Nox‐1, Nox‐2, Nox‐4, P22phox, and P47phox, and Giα proteins in VSMC from SHR were also attenuated by SNP treatment. On the other hand, SNP treatment augmented the decreased levels of intracellular NO, eNOS, and cGMP in VSMC from SHR. These results suggest that SNP treatment attenuates the development of high BP in SHR through the elevation of intracellular levels of cGMP and inhibition of the enhanced levels of Giα proteins and nitroxidative stress.

There is a growing body of evidence supporting an intimate association of immune activation with the pathogenesis of cardiovascular diseases, including atherosclerosis. Uptake of oxidized low-density lipoprotein (oxLDL) through scavenging receptors promotes the formation of mature lipid-laden macrophages, which subsequently leads to exacerbation of regional inflammation and atherosclerotic plaque formation. In this study, we first examined changes in the mRNA level of the lectin-like oxLDL receptor-1 (LOX-1) in the mouse macrophage cell line RAW264.7 and the human PMA-induced macrophage cell line THP-1 after LPS stimulation. LPS significantly up-regulated LOX-1 mRNA in RAW264.7 cells; LOX-1 cell-surface protein expression was also increased. Flow cytometry and fluorescence microscopy analyses showed that cellular uptake of fluorescence (Dil)-labeled oxLDL was significantly augmented with LPS stimulation. The augmented uptake of Dil-oxLDL was almost completely abrogated by treatment with an anti-LOX-1 antibody. Of note, knockdown of Erk1/2 resulted in a significant reduction of LPS-induced LOX-1 up-regulation. Treatment with U0126, a specific inhibitor of MEK, significantly suppressed LPS-induced expression of LOX-1 at both the mRNA and protein levels. Furthermore, LOX-1 promoter activity was significantly augmented by LPS stimulation; this augmentation was prevented by U0126 treatment. Similar results were also observed in human PMA-induced THP-1 macrophages. Taken together, our results indicate that LPS up-regulates LOX-1, at least in part through activation of the Erk1/2 signaling pathway, followed by augmented cellular oxLDL uptake, thus highlighting a critical role of TLR4-mediated aberrant LOX-1 signaling in the pathogenesis of atherosclerosis.

Although chronic arsenic exposure is a well-known risk factor for cardiovascular diseases, including atherosclerosis, the molecular mechanism underlying arsenic-induced atherosclerosis remains obscure. Therefore, this study aimed to elucidate this molecular mechanism. We examined changes in the mRNA level of the lectin-like oxidized LDL (oxLDL) receptor (LOX-1) in a mouse aortic endothelial cell line, END-D, after sodium arsenite (SA) treatment. SA treatment significantly upregulated LOX-1 mRNA expression; this finding was also verified at the protein expression level. Flow cytometry and fluorescence microscopy analyses showed that the cellular uptake of fluorescence (Dil)-labeled oxLDL was significantly augmented with SA treatment. In addition, an anti-LOX-1 antibody completely abrogated the augmented uptake of Dil-oxLDL. We observed that SA increased the levels of the phosphorylated forms of nuclear factor of kappa light polypeptide gene enhancer in B cells (NF-κB)/p65. SA-induced upregulation of LOX-1 protein expression was clearly prevented by treatment with an antioxidant, N-acetylcysteine (NAC), or an NF-κB inhibitor, caffeic acid phenethylester (CAPE). Furthermore, SA-augmented uptake of Dil-oxLDL was also prevented by treatment with NAC or CAPE. Taken together, our results indicate that arsenic upregulates LOX-1 expression through the reactive oxygen species-mediated NF-κB signaling pathway, followed by augmented cellular oxLDL uptake, thus highlighting a critical role of the aberrant LOX-1 signaling pathway in the pathogenesis of arsenic-induced atherosclerosis.

The properties of constitutive promoters within adeno-associated viral (AAV) vectors have not yet been fully characterized. In this study, AAV vectors, in which enhanced GFP expression was directed by one of the six constitutive promoters (human β-actin, human elongation factor-1α, chicken β-actin combined with cytomegalovirus early enhancer, cytomegalovirus (CMV), simian virus 40, and herpes simplex virus thymidine kinase), were constructed and introduced into the HCT116, DLD-1, HT-1080, and MCF-10A cell lines. Quantification of GFP signals in infected cells demonstrated that the CMV promoter produced the highest GFP expression in the six promoters and maintained relatively high GFP expression for up to eight weeks after infection of HCT116, DLD-1, and HT-1080. Exogenous human CDKN2A gene expression was also introduced into DLD-1 and MCF-10A in a similar pattern by using AAV vectors bearing the human β-actin and the CMV promoters. The six constitutive promoters were subsequently placed upstream of the neomycin resistance gene within AAV vectors, and HCT116, DLD-1, and HT-1080 were infected with the resulting vectors. Of the six promoters, the CMV promoter produced the largest number of G418-resistant colonies in all three cell lines. Because AAV vectors have been frequently used as a platform to construct targeting vectors that permit gene editing in human cell lines, we lastly infected the three cell lines with AAV-based targeting vectors against the human PIGA gene in which one of the six promoters regulate the neomycin resistance gene. This assay revealed that the CMV promoter led to the lowest PIGA gene targeting efficiency in the investigated promoters. These results provide a clue to the identification of constitutive promoters suitable to express exogenous genes with AAV vectors, as well as those helpful to conduct efficient gene targeting using AAV-based targeting vectors in human cell lines.

Although chronic arsenic exposure is a well-known risk for cardiovascular disease and has a strong correlation with hypertension, the molecular pathogenesis underlying arsenic exposure-induced hypertension remains poorly understood. To delineate the pathogenesis, we examined changes in the mRNA levels of 2 angiotensin II Type I receptor (AT1R) subtypes, AT1AR and AT1BR, in a mouse aortic endothelial cell line, END-D. Quantitative real-time PCR analysis revealed significant increases in the mRNA levels of 2 AT1R subtypes, AT1AR and AT1BR following sodium arsenite (SA) treatment. Flow cytometry analysis revealed that SA increases the generation of reactive oxygen species (ROS) in a dose-dependent manner. In addition, western blot analysis revealed that SA enhances the phosphorylations of c-Jun N-terminal kinases (JNK) and activated protein 1 (AP-1). These phosphorylations were inhibited by N-acetylcysteine (NAC), an anti-oxidant. Finally, SA-induced AT1R expression was found to be prevented both by NAC and specific JNK inhibitor, SP6001325, strongly indicating that AT1R upregulation is a result of the ROS-mediated activation of the JNK signaling pathway. Taken together, our results indicate that arsenic indeed upregulates the AT1R expression, thus highlighting a role of arsenic-induced aberrant AT1R signaling in the pathogenesis of hypertension.

β-actin (ACTB) is one of the genes expressed most abundantly and ubiquitously in human non-muscular tissues. Here, we investigated the long-term activity of a 550-bp-long human ACTB promoter region in human cells in comparison with other commonly used constitutive promoters. We first constructed plasmid vectors expressing enhanced green fluorescent protein (GFP) driven by one of the 5 promoters, human ACTB, human elongation factor-1α (EF1α), cytomegalovirus early enhancer/chicken β-actin (CAG), cytomegalovirus (CMV), and herpes simplex virus thymidine kinase, and transfected them into multiple human somatic cell lines. Stable transfectants were maintained for 45 days, and GFP signals from the cells were quantified by fluorescence flow cytometry. GFP signals driven by the human ACTB and the CMV promoters were also compared over time for up to 60 days following transfection. We observed robust, prolonged transcriptional activity with the human ACTB promoter that is comparable to the human EF1α and the CAG promoters and significantly more stable than the CMV promoter.

Chronic arsenic (As) exposure affects the endothelial system causing several diseases. Big endothelin-1 (Big ET-1), the biological precursor of endothelin-1 (ET-1) is a more accurate indicator of the degree of activation of the endothelial system. Effect of As exposure on the plasma Big ET-1 levels and its physiological implications have not yet been documented. We evaluated plasma Big ET-1 levels and their relation to hypertension and skin lesions in As exposed individuals in Bangladesh. A total of 304 study subjects from the As-endemic and non-endemic areas in Bangladesh were recruited for this study. As concentrations in water, hair and nails were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The plasma Big ET-1 levels were measured using a one-step sandwich enzyme immunoassay kit. Significant increase in Big ET-1 levels were observed with the increasing concentrations of As in drinking water, hair and nails. Further, before and after adjusting with different covariates, plasma Big ET-1 levels were found to be significantly associated with the water, hair and nail As concentrations of the study subjects. Big ET-1 levels were also higher in the higher exposure groups compared to the lowest (reference) group. Interestingly, we observed that Big ET-1 levels were significantly higher in the hypertensive and skin lesion groups compared to the normotensive and without skin lesion counterpart, respectively of the study subjects in As-endemic areas. Thus, this study demonstrated a novel dose-response relationship between As exposure and plasma Big ET-1 levels indicating the possible involvement of plasma Big ET-1 levels in As-induced hypertension and skin lesions. (C) 2012 Elsevier Inc. All rights reserved.

The present study was undertaken to evaluate the protective effect of turmeric powder on arsenic toxicity through mice model. Swiss albino male mice were divided into four groups. The first group was used as control, while groups 2, 3, and 4 were treated with turmeric powder (T, 50 mg/kg body weight/day), sodium arsenite (Sa, 10 mg/kg body weight/day) and turmeric plus Sa (T+Sa), respectively. Results showed that oral administration of Sa reduced the weight gain of the mice compared to the control group and food supplementation of turmeric prevented the reduction of weight gain. Turmeric abrogated the Sa-induced elevation of serum urea, glucose, triglyceride (TG) level and alanine aminotransferase (ALT) activity except the activity of alkaline phosphatase (ALP). Turmeric also prevented the Sa-induced perturbation of serum butyryl cholinesterase activity (BChE). Therefore, ameliorating effect of turmeric on Sa-treated mice suggested the future application of turmeric to reduce or to prevent arsenic toxicity in human.

Arsenic is a potent environmental pollutant that has caused one of the largest public health poisonings in the history of human civilization, affecting tens of millions of people worldwide especially in Bangladesh. Lactate dehydrogenase (LDH) in blood plays an important role in predicting cell or organ damage and as an important clue to the diagnosis of a variety of cancers. However, effect of chronic arsenic exposure on the LDH level in blood has not yet been documented. Since the chronic arsenic exposure is associated with organ damages and multi-site cancers, this research aimed at assaying the plasma level of LDH activity in the population who were exposed to arsenic chronically in Bangladesh. A total of 185 individuals living in arsenic-exposed areas and 121 individuals living in non-exposed area in Bangladesh were recruited as study subjects. Arsenic content in drinking water, hair and nails were estimated by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) and LDH activity was assayed by a spectrophotometer. Significant increase in LDH activity was observed with increasing concentrations of arsenic in water, hair and nails. Further, the study subjects were split into four groups based on the three ways of each exposure metrics (water, hair and nail arsenic concentrations) where the study subjects in the non-exposed area were used as a reference (lowest exposure) group. LDH activity was found to be increased in the higher exposure groups of water and hair arsenic concentrations. LDH activity was also increased at low to medium exposure groups of nail arsenic concentrations.Thus, the elevated plasma LDH activity might be helpful for the early prognosis of organ or tissue damage in the individuals who were exposed to arsenic chronically.

Background Chronic arsenic exposure has been shown to cause liver damage. However, serum hepatic enzyme activity as recognized on liver function tests (LFTs) showing a dose-response relationship with arsenic exposure has not yet been clearly documented. The aim of our study was to investigate the dose-response relationship between arsenic exposure and major serum enzyme marker activity associated with LFTs in the population living in arsenic-endemic areas in Bangladesh. Methods A total of 200 residents living in arsenic-endemic areas in Bangladesh were selected as study subjects. Arsenic concentrations in the drinking water, hair and nails were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The study subjects were stratified into quartile groups as follows, based on concentrations of arsenic in the drinking water, as well as in subjects' hair and nails: lowest, low, medium and high. The serum hepatic enzyme activities of alkaline phosphatase (ALP), aspartate transaminase (AST) and alanine transaminase (ALT) were then assayed. Results Arsenic concentrations in the subjects' hair and nails were positively correlated with arsenic levels in the drinking water. As regards the exposure-response relationship with arsenic in the drinking water, the respective activities of ALP, AST and ALT were found to be significantly increased in the high-exposure groups compared to the lowest-exposure groups before and after adjustments were made for different covariates. With internal exposure markers (arsenic in hair and nails), the ALP, AST and ALT activity profiles assumed a similar shape of dose-response relationship, with very few differences seen in the higher groups compared to the lowest group, most likely due to the temporalities of exposure metrics. Conclusions The present study demonstrated that arsenic concentrations in the drinking water were strongly correlated with arsenic concentrations in the subjects' hair and nails. Further, this study revealed a novel exposure- and dose- response relationship between arsenic exposure metrics and serum hepatic enzyme activity. Elevated serum hepatic enzyme activities in the higher exposure gradients provided new insights into arsenic-induced liver toxicity that might be helpful for the early prognosis of arsenic-induced liver diseases.

The present study was undertaken to evaluate the protective effect of turmeric powder on arsenic toxicity through mice model. Swiss albino male mice were divided into four groups. The first group was used as control, while groups 2, 3, and 4 were treated with turmeric powder (T, 50mg/kg body weight/day), sodium arsenite (Sa, 10mg/kg body weight/day) and turmeric plus Sa (T+Sa), respectively. Results showed that oral administration of Sa reduced the weight gain of the mice compared to the control group and food supplementation of turmeric prevented the reduction of weight gain. Turmeric abrogated the Sa-induced elevation of serum urea, glucose, triglyceride (TG) level and alanine aminotransferase (ALT) activity except the activity of alkaline phosphatase (ALP). Turmeric also prevented the Sa-induced perturbation of serum butyryl cholinesterase activity (BChE). Therefore, ameliorating effect of turmeric on Sa-treated mice suggested the future application of turmeric to reduce or to prevent arsenic toxicity in human. DOI: 10.3329/bmrcb.v36i3.7287Bangladesh Med Res Counc Bull 2010; 36: 82-88

Objective: To evaluate the protective role of leaves of Moringa oleifera (M. oleifera) Lam. against arsenic-induced toxicity in mice. Methods: Swiss albino male mice were divided into four groups. The first group was used as non-treated control group while, the second, third, and fourth groups were treated with M. oleifera leaves (50 mg/kg body weight per day), sodium arsenite (10 mg/kg body weight per day) and sodium arsenite plus M. oleifera leaves, respectively. Serum indices related to cardiac, liver and renal functions were analyzed to evaluate the protective effect of Moringa leaves on arsenic-induced effects in mice. Results: It revealed that food supplementation of M. oleifera leaves abrogated the arsenic-induced elevation of triglyceride, glucose, urea and the activities of alkaline phospatase, aspartate aminotransferase and alanine aminotransferase in serum. M. oleifera leaves also prevented the arsenic-induced perturbation of serum butyryl cholinesterase activity, total cholesterol and high density lipoprotein cholesterol. Conclusions: The results indicate that the leaves of M. oleifera may be useful in reducing the effects of arsenic-induced toxicity.