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Background: Chronic exposure to arsenic is associated with cancer and hypertension. Growing evidence suggests that altered methylation in long interspersed nuclear element-1 (LINE-1) is involved in many types of disorders, including cardiovascular disease. Here we evaluated the association between arsenic exposure and LINE-1 methylation levels, especially in relation to blood pressure (BP)., Methods: A total of 236 subjects (175 from arsenic-endemic areas and 61 from a non-endemic area) in rural Bangladesh were recruited. The subjects' arsenic exposure levels (i.e., drinking water, hair and nail arsenic concentrations) were measured by inductively coupled plasma mass spectroscopy. The subjects' LINE-1 methylation levels were determined by pyrosequencing., Results: The average LINE-1 methylation levels of the subjects living in the arsenic-endemic areas were significantly (p < 0.01) lower than those of the subjects living in the non-endemic area. In a sex-stratified analysis, the arsenic exposure levels in female but not male subjects showed a significant inverse association with LINE-1 methylation levels before (water arsenic: p < 0.01, hair arsenic: p < 0.05, nail arsenic: p < 0.001) and after (water arsenic: p < 0.01, hair arsenic: p < 0.05, nail arsenic: p < 0.001) adjustment for age, body mass index and smoking. Analyses examining interactions among arsenic levels, BP and LINE-1 methylation showed that arsenic-related elevated levels of BP were associated with LINE-1 hypomethylation., Conclusions: Our findings demonstrated that chronic exposure to arsenic was inversely associated with LINE-1 methylation levels in blood leukocyte DNA and this was more pronounced in females than males; in addition, the decreased levels of LINE-1 methylation might be involved in the arsenic-induced elevation of BP.

Background: Interleukin‐1 alpha (IL‐1α) is a pro‐inflammatory cytokine that can activate immune effector cells and trigger anti‐tumor immune responses. However, dose‐limiting toxicities including cytokine storm and hypotension has limited its use in the clinic as a cancer therapy. We propose that polymeric microparticle (MP)‐based delivery of IL‐1α will suppress the acute pro‐inflammatory side effects by allowing for slow and controlled release of IL‐1α systemically, while simultaneously triggering an anti‐tumor immune response. Methods: Polyanhydride copolymers composed of 1,6‐bis‐(p‐carboxyphenoxy)‐hexane:sebacic 20:80 (CPH:SA 20:80) was utilized to fabricate MPs. Recombinant IL‐1α (rIL‐1α) was encapsulated into CPH:SA 20:80 MPs (IL‐1α‐MPs) and the MPs were characterized by size, charge, loading efficiency, and in‐vitro release and activity of IL‐1α. IL‐1α‐MPs were injected intraperitonially into head and neck squamous cell carcinoma (HNSCC)‐bearing C57Bl/6 mice and monitored for changes in weight, tumor growth, circulating cytokines/chemokines, hepatic and kidney enzymes, blood pressure, heart rate, and tumor‐infiltrating immune cells. Results: CPH:SA IL‐1α‐MPs demonstrated sustained release kinetics of IL‐1α (100% protein released over 8–10 days) accompanied by minimal weight loss and systemic inflammation compared to rIL‐1α‐treated mice. Blood pressure measured by radiotelemetry in conscious mice demonstrates that rIL‐1α‐induced hypotension was prevented in IL‐1α‐MP‐treated mice. Liver and kidney enzymes were within normal range for all control and cytokine‐treated mice. Both rIL‐1α and IL‐1α‐MP‐treated mice showed similar delays in tumor growth and similar increases in tumor‐infiltrating CD3+ T cells, macrophages, and dendritic cells. Conclusions: CPH:SA‐based IL‐1α‐MPs generated a slow and sustained systemic release of IL‐1α resulting in reduced weight loss, systemic inflammation, and hypotension accompanied by an adequate anti‐tumor immune response in HNSCC‐tumor bearing mice. Therefore, MPs based on CPH:SA formulations may be promising as delivery vehicles for IL‐1α to achieve safe, effective, and durable antitumor responses for HNSCC patients. [ABSTRACT FROM AUTHOR]

Chronic exposure to arsenic is associated with increased morbidity and mortality from cardiovascular disease (CVD); however, plausible biomarker for early prediction and the underlying mechanism of arsenic-related CVD have not yet been clearly understood. Endothelial dysfunction plays a central role in the development of CVD. We hypothesized that endothelial damage or dysfunction is an important aspect and may be an early event of arsenic-related CVD. Soluble thrombomodulin (sTM) in serum is thought to be a specific and stable marker for endothelial damage or dysfunction. This study was designed to evaluate the association between chronic exposure to arsenic and sTM among human subjects in arsenic-endemic and non-endemic rural areas in Bangladesh. A total of 321 study subjects (217 from arsenic-endemic areas and 104 from a non-endemic area) were recruited. Subjects’ arsenic exposure levels (i.e., drinking water, hair and nail arsenic concentrations) were measured by Inductively Coupled Plasma Mass Spectroscopy. The subjects’ serum sTM levels were quantified by immunoassay kit. The average sTM levels of the subjects in arsenic-endemic and non-endemic areas were 4.58 ± 2.20 and 2.84 ± 1.29 (ng mL-1) respectively, and the difference was significant (p<0.001). Arsenic exposure levels showed a significant (water arsenic: rs = 0.339, p<0.001, hair arsenic: rs = 0.352, p<0.001 and nail arsenic: rs = 0.308, p<0.001) positive associations with sTM levels. Soluble TM levels were higher in the higher exposure gradients if we stratified the subjects into tertile groups (low, medium and high) based on the arsenic concentrations of the subjects’ drinking water, hair and nails. Finally, increased levels of sTM were negatively correlated with high density lipoprotein cholesterol (HDL-C), and positively correlated with intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). Results of this study show that chronic exposure to arsenic has mild to moderate association with sTM levels. [ABSTRACT FROM AUTHOR]

Background: Chronic exposure to arsenic is associated with cancer and hypertension. Growing evidence suggests that altered methylation in long interspersed nuclear element-1 (LINE-1) is involved in many types of disorders, including cardiovascular disease. Here we evaluated the association between arsenic exposure and LINE-1 methylation levels, especially in relation to blood pressure (BP).Methods: A total of 236 subjects (175 from arsenic-endemic areas and 61 from a non-endemic area) in rural Bangladesh were recruited. The subjects' arsenic exposure levels (i.e., drinking water, hair and nail arsenic concentrations) were measured by inductively coupled plasma mass spectroscopy. The subjects' LINE-1 methylation levels were determined by pyrosequencing.Results: The average LINE-1 methylation levels of the subjects living in the arsenic-endemic areas were significantly (p < 0.01) lower than those of the subjects living in the non-endemic area. In a sex-stratified analysis, the arsenic exposure levels in female but not male subjects showed a significant inverse association with LINE-1 methylation levels before (water arsenic: p < 0.01, hair arsenic: p < 0.05, nail arsenic: p < 0.001) and after (water arsenic: p < 0.01, hair arsenic: p < 0.05, nail arsenic: p < 0.001) adjustment for age, body mass index and smoking. Analyses examining interactions among arsenic levels, BP and LINE-1 methylation showed that arsenic-related elevated levels of BP were associated with LINE-1 hypomethylation.Conclusions: Our findings demonstrated that chronic exposure to arsenic was inversely associated with LINE-1 methylation levels in blood leukocyte DNA and this was more pronounced in females than males; in addition, the decreased levels of LINE-1 methylation might be involved in the arsenic-induced elevation of BP. [ABSTRACT FROM AUTHOR]