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1.
Environ Sci Pollut Res Int ; 29(39): 58484-58513, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35778660

RESUMO

Polycystic ovarian syndrome (PCOS) is a complex multifactorial disorder of unknown pathogenesis in which genetic and environmental factors contribute synergistically to its phenotypic expressions. Endocrine-disrupting chemicals (EDCs), a group of widespread pollutants freely available in the environment and consumer products, can interfere with normal endocrine signals. Extensive evidence has shown that EDCs, environmental contributors to PCOS, can frequently induce ovarian and metabolic abnormalities at low doses. The current research on environmental EDCs suggests that there may be link between EDC exposure and PCOS, which calls for more human bio-monitoring of EDCs using highly sophisticated analytical techniques for the identification and quantification and to discover the underlying pathophysiology of the disease. This review briefly elaborated on the general etiology of PCOS and listed various epidemiological and experimental data from human and animal studies correlating EDCs and PCOS. This review also provides insights into various analytical tools and sample preparation techniques for biomonitoring studies for PCOS risk assessment. Furthermore, we highlight the role of metabolomics in disease-specific biomarker discovery and its use in clinical practice. It also suggests the way forward to integrate biomonitoring studies and metabolomics to underpin the role of EDCs in PCOS pathophysiology.


Assuntos
Disruptores Endócrinos , Poluentes Ambientais , Síndrome do Ovário Policístico , Animais , Disruptores Endócrinos/toxicidade , Sistema Endócrino , Poluentes Ambientais/toxicidade , Feminino , Humanos , Síndrome do Ovário Policístico/induzido quimicamente
2.
Environ Pollut ; 264: 114682, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32380400

RESUMO

Perchlorate occurs naturally in the environment in deposits of nitrate and can be formed in the atmosphere and precipitate into soil. However, little is known about the occurrence and levels of perchlorate in soils and fertilizers in Chile and its impacts on agricultural systems and food safety. In this study, concentrations of perchlorate were determined in 101 surface soils and 17 fertilizers [nitrogenous (n = 8), nitrogen-phosphorous-potassium (NPK; n = 3), phosphate (n = 2) and non-nitrogenous (n = 4)] collected across Chile from 2017 to 2018. Our results show that perchlorate was detected mainly in agricultural soils (mean: 0.32 ng g-1), grassland rotation sites (0.41 ngg-1) and urban locations (0.38 ng g-1). Interestingly, elevated concentrations of perchlorate (9.66 and 54.0 ng g-1) were found in agricultural soils. All fertilizers contained perchlorate: nitrogenous fertilizers (mean: 32.6 mg kg-1), NPK (mean: 12.6 mg kg-1), non-nitrogenous fertilizers (mean: 10.2 mg kg-1) and phosphates (mean: 11.5 mg kg-1). Only one type of nitrogenous fertilizer (KNO3: 95.3 mg kg-1) exceeded the international regulation limit (50 mg kg-1). For two agronomic practices, the content of perchlorate in lettuce increased as the fertilizer application rate increased, with fertigation promoting a more significant accumulation. However, the concentrations generally remained below regulatory values. Our results suggest that fertilizers constitute an important source of perchlorate in soils.


Assuntos
Lactuca , Solo , Agricultura , Chile , Fertilizantes/análise , Percloratos
3.
Pediatr Res ; 81(6): 857-864, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28099427

RESUMO

BACKGROUND: The health effects of bisphenol A (BPA) and di-(2-ethylhexyl) phthalate (DEHP) have been studied extensively in children. The impact of other chemicals in these two classes has not been investigated as fully. METHODS: We conducted a cross-sectional pilot study of 10-13 y old healthy children. We assessed descriptive, univariable, and multivariable associations of urinary metabolites of bisphenols and phthalates with oxidant stress, insulin resistance, body mass, and endothelial dysfunction. Possible associations with brachial artery distensibility, pulse wave velocity (markers of vascular stiffness), and serum endothelial cell-derived microparticle levels were also assessed. RESULTS: We enrolled 41 participants, 12.1 ± 1.0 y, most of whom were Mexican Americans (42%) or other Hispanics (34%). Increased BPA levels were associated with increased levels of F2-isoprostane (ng/ml) (P = 0.02), with a similar trend for DEHP metabolites. Each log unit increase of high molecular weight (HMW) phthalate metabolites was associated with a 0.550 increase in Homeostatic Model Assessment of insulin resistance (HOMA-IR) units (P = 0.019) and altered circulating levels of activated endothelial cell-derived microparticles (% per ml) (P = 0.026). Bisphenol S (BPS), a replacement for BPA, was associated with increased albumin (mg):creatinine (g) ratio (P = 0.04). Metabolites of HMW phthalates were also associated with decreased brachial artery distensibility (P = 0.047). CONCLUSION: Exposure to bisphenols and phthalates, including a BPA replacement, is associated with increased oxidant stress, insulin resistance, albuminuria, as well as disturbances in vascular function in healthy children.


Assuntos
Compostos Benzidrílicos/toxicidade , Dietilexilftalato/toxicidade , Endotélio Vascular/efeitos dos fármacos , Resistência à Insulina , Estresse Oxidativo/efeitos dos fármacos , Fenóis/toxicidade , Adolescente , Criança , Estudos Transversais , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Masculino , Projetos Piloto
4.
PLoS One ; 9(3): e89351, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24622734

RESUMO

Although the anti-cancer effects of curcumin has been shown in various cancer cell types, in vitro, pre-clinical and clinical studies showed only a limited efficacy, even at high doses. This is presumably due to low bioavailability in both plasma and tissues, particularly due to poor intracellular accumulation. A variety of methods have been developed to achieve the selective targeting of drugs to cells and mitochondrion. We used a novel approach by conjugation of curcumin to lipophilic triphenylphosphonium (TPP) cation to facilitate delivery of curcumin to mitochondria. TPP is selectively taken up by mitochondria driven by the membrane potential by several hundred folds. In this study, three mitocurcuminoids (mitocurcuminoids-1, 2, and 3) were successfully synthesized by tagging TPP to curcumin at different positions. ESI-MS analysis showed significantly higher uptake of the mitocurcuminoids in mitochondria as compared to curcumin in MCF-7 breast cancer cells. All three mitocurcuminoids exhibited significant cytotoxicity to MCF-7, MDA-MB-231, SKNSH, DU-145, and HeLa cancer cells with minimal effect on normal mammary epithelial cells (MCF-10A). The IC50 was much lower for mitocurcuminoids when compared to curcumin. The mitocurcuminoids induced significant ROS generation, a drop in ΔØm, cell-cycle arrest and apoptosis. They inhibited Akt and STAT3 phosphorylation and increased ERK phosphorylation. Mitocurcuminoids also showed upregulation of pro-apoptotic BNIP3 expression. In conclusion, the results of this study indicated that mitocurcuminoids show substantial promise for further development as a potential agent for the treatment of various cancers.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Curcumina/farmacologia , Curcumina/farmacocinética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Disponibilidade Biológica , Transporte Biológico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Curcumina/química , Curcumina/metabolismo , Citosol/efeitos dos fármacos , Citosol/metabolismo , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/metabolismo
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