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- The role of adipose tissue analysis on Environmental Pollutants Biomonitoring in women: The European scenarioPublication . Sousa, Sara; Maia, Maria Luz; Delerue-Matos, Cristina; Calhau, Conceição; Domingues, Valentina F.Humans are exposed every day to assorted environmental pollutants namely, polychlorinated biphenyls (PCB), organochlorine pesticides (OCP), brominated flame-retardants (BFR), polycyclic aromatic hydrocarbons (PAH), synthetic musks, heavy metals (e.g. cadmium) and plastic additives (e.g. bisphenol A, BPA). Besides environmental persistence, biomagnification and bioaccumulative properties, these pollutants are classified as endocrine disruptors (EDs), metabolic disruptors, neurologic disruptors. These compounds affect the normal function of several mechanisms in the human body being linked to human health issues as cancer development (e.g. breast, uterine and endometrial), miscarriage, birth defects, premature delivery and infertility. In order to prevent future health issue of women and possible progeny, the assessment of EDs accumulated is essential, particularly in adipose tissue. These samples have been referred as the ideal matrix to establish over time accumulation and long-term exposure of persistent and non-persistent lipophilic EDs. However, the invasive sample collection procedure and methodology processing discourages the usage of this matrix for biomonitoring studies. In this review, a Web of Science search without any publishing year restriction on the analysis in adipose tissue of PCB, OCP, BPA, cadmium, BFR and synthetic musks was performed. A total of 313 studies were found, 158 were European studies from which the studies with data on women EDs accumulation were selected for detailed analysis (n = 90). The results were structured and presented in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The present paper is an overview on the existent EDs analytical methods and levels accumulated in women adipose tissue, with the correspondent health implications across Europe. The limits of detection and quantification were compared and a discussion with results obtained about the presence of ED was performed
- Impact of brominated flame retardants on lipid metabolism: An in vitro approachPublication . Maia, Maria Luz; Sousa, Sara; Pestana, Diogo; Faria, Ana; Teixeira, Diana; Delerue-Matos, Cristina; Domingues, Valentina; Calhau, ConceiçãoBrominated flame retardants (BFRs) are chemicals employed to lower the flammability of several objects. These endocrine disruptor chemicals are lipophilic and persistent in the environment. Due to these characteristics some have been restricted or banned by the European Union, and replaced by several new chemicals, the novel BFRs (NBFRs). BFRs are widely detected in human samples, such as adipose tissue and some were linked with altered thyroid hormone levels, liver toxicity, diabetes and metabolic syndrome in humans. However, the disturbance in lipid metabolism caused by BFRs with emphases to NBFRs remains poorly understood. In this study, we used a pre-adipocyte (3T3-L1) cell line and a hepatocyte (HepG2) cell line to investigate the possible lipid metabolism disruption caused by four BFRs: hexabromobenzene (HBB), pentabromotoluene (PBT), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB) and hexabromocyclododecane (HBCD). For that purpose, proliferation and Oil Red O assays, as well as, medium fatty acids profile evaluation using Gas chromatography and RNA extraction for quantitative RT-PCR assays were performed. We detected a significant reduction in the proliferation of preadipocytes and an increased lipid accumulation during differentiation caused by HBB. This BFR also lead to a significant increased expression of IL-1β and decreased expression of PGC-1α and adiponectin. Nevertheless, PBT, TBB and HBCD show to increase lipid accumulation in hepatocytes. PBT also display a significant increase of PPARγ gene expression. Lipid accumulation in the cells can occur by diverse mechanisms depending on the BFR. These results highlight the importance of endocrine disruptor compounds in obesity etiopathogeny.
- Organochlorine pesticides, brominated flame retardants, synthetic musks and polycyclic aromatic hydrocarbons in shrimps. An overview of occurrence and its implication on human exposurePublication . Maia, Maria Luz; Sousa, Sara; Correia-Sá, Maria Luísa; Delerue-Matos, Cristina; Calhau, Conceição; Domingues, Valentina FernandesShrimps are widely distributed in coastal areas, estuaries and rivers. Although this shellfish is a good source of nutrients, it can also accumulate environmental contaminants, such as organochlorine pesticides (OCPs), brominated flame retardants (BFRs), synthetic musks (SMs) and polycyclic aromatic hydrocarbons (PAHs). Due to their bioaccumulative properties, these pollutants are endocrine disruptors. In this review, an overview of the world's shrimp market, pollutants legislation and values found in shrimp samples will be discussed. Shrimps analysed from all continents showed the presence of contaminants, Asia being the continent with the highest values reported. The concentration values reached a maximum of 26100 ng/g wet weight (ww) for OCPs, of 226.45 ng/g ww for BFRs, of 12.1 ng/g ww for SMs and of 50650 ng/g ww for PAHs. Exposure data and risk, taken from different studies, are very variable and indicate that shrimp's consumption may represent a risk especially in certain geographic areas.
- Brominated flame retardants effect in MCF-7 cells: Impact on vitamin D pathwayPublication . Sousa, Sara; Maia, Maria Luz; Pestana, Diogo; Teixeira, Diana; Ângelo-Dias, Miguel; Martins, Catarina; Borrego, Luís Miguel; Delerue-Matos, Cristina; Calhau, Conceição; Domingues, Valentina; Faria, AnaBrominated flame retardants (BFRs) are persistent environmental pollutants, allowing a constant human exposure which carries several health risks, including the occurrence of breast cancer and vitamin D deficiency. Vitamin D inhibits cell growth and is negatively associated with breast cancer risk. The effect of BFRs in breast cancer and vitamin D pathway is still poorly understood. MCF-7 cells were treated with hexabromocyclododecane (HBCD), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB), hexabromobenzene (HBB) and pentabromotoluene (PBT) using short and long-term exposure protocols. Viability, proliferation, migration, cell cycle and gene expression were assessed. Gene expression of hVDBP and hCYP2R1 was also evaluated in hepatocytes. Long-term exposure of MCF-7 cells to HBB increased cell proliferation and migration, consequently increasing MMP-9 expression. The vitamin D pathway was also altered by BFRs: cells appeared less prepared to activate and transport vitamin D and the signaling, action and inactivation mechanisms were diminished in the presence of BFRs. Untreated MCF-7 cells showed cell cycle arrest in phase G0/G1 in the presence of activated vitamin D. However, when MCF-7 cells were exposed to BFRs, cell cycle was arrested in phase G2/M, possibly due to DNA damage. Nonetheless, calcitriol seems to be able to mitigate the effect of some BFRs exposure, e.g. PBT