Determining maternal concentrations of per- and polyfluoroalkyl substances (PFASs) and the relative impact of various demographic and dietary predictors is important for assessing fetal exposure and for developing proper lifestyle advisories for pregnant women. This study was conducted to investigate maternal PFAS concentrations and their predictors in years when the production and use of several PFASs declined, and to assess the relative importance of significant predictors. Blood from 391 pregnant women participating in The Northern Norway Mother-and-Child Contaminant Cohort Study (MISA) was collected in the period 2007-2009 and serum analyses of 26 PFASs were conducted. Associations between PFAS concentrations, sampling date, and demographic and dietary variables were evaluated by multivariate analyses and linear models including relevant covariates. Parity was the strongest significant predictor for all the investigated PFASs, and nulliparous women had higher concentrations compared to multiparous women (10 ng/mL versus 4.5 ng/mL in median PFOS, respectively). Serum concentrations of PFOS and PFOA of women recruited day 1-100 were 25% and 26% higher, respectively, compared to those women recruited in the last 167 days of the study (day 601-867), and the concentrations of PFNA, PFDA and PFUnDA increased with age. Dietary predictors explained 0-17% of the variation in concentrations for the different PFASs. Significantly elevated concentrations of PFOS, PFNA, PFDA and PFUnDA were found among high consumers of marine food. The concentrations of PFHxS, PFHpS and PFNA were also increased in high consumers of game and elevated concentrations of PFHpS and PFOS were detected in high consumers of white meat. Study subjects with a high intake of salty snacks and beef had significantly higher concentrations of PFOA. The present study demonstrates that parity, sampling date and birth year are the most important predictors for maternal PFAS concentrations in years following a decrease in production and use of several PFASs. Further, dietary predictors of PFAS concentrations were identified and varied in importance according to compound.
IntroductionChemerin is a chemotactic peptide which directs leukocytes expressing the chemokine-like receptor ChemR23 towards sites of inflammation. ChemR23 is a G protein-coupled receptor which binds several different ligands, and it is also expressed by other cell types such as adipocytes. In addition to chemotaxis, recent reports suggest that ChemR23 is capable of mediating either inflammatory or anti-inflammatory effects, depending on the type of ligand it binds. In the present study, we aimed to clarify whether human chondrocytes express ChemR23 and chemerin, and whether chemerin/ChemR23 signalling could affect secretion of inflammatory mediators.MethodsTissue sections were taken from human knee joints and labelled with antibodies towards chemerin and ChemR23. Chondrocytes from cartilage tissue were isolated, cultured and assessed for chemerin and ChemR23 expression by PCR and immunolabelling. Receptor activation and intracellular signalling were studied by assessment of phosphorylated mitogen activated protein kinases (MAPKs) and phosphorylated Akt after stimulating cells with recombinant chemerin21-157. Biological effects of chemerin21-157 were investigated by measuring secretion of pro-inflammatory cytokines and metalloproteases in cell supernatants.ResultsBoth serially cultured human articular chondrocytes and resident cells in native cartilage expressed chemerin and ChemR23. Stimulating cells with chemerin21-157 resulted in phosphorylation of p44/p42 MAPKs (ERK 1/2) and Akt (Ser 473). Also, significantly enhanced levels of the pro-inflammatory cytokines interleukin-6 (IL-6), interleukin-8 (IL-8), tumour necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), and the matrix metalloproteases MMP-1, MMP-2, MMP-3, MMP-8 and MMP-13 were detected.ConclusionsThese results demonstrate that human chondrocytes express both the receptor ChemR23 and the ligand chemerin. Chemerin21-157 stimulation engaged signal-transduction pathways that further promoted inflammatory signalling in chondrocytes, as judged by an enhanced secretion of cytokines and metalloproteases. Taken together, the previously reported chemotaxis and the present findings suggest that the receptor and its ligand may play pivotal roles in joint inflammation.
BackgroundCancer-Associated Fibroblasts (CAFs) are significant components of solid malignancies and play central roles in cancer sustainability, invasion and metastasis. In this study we have investigated the invasive capacity and matrix remodelling properties of human lung CAFs after exposure to ablative doses of ionizing radiation (AIR), equivalent to single fractions delivered by stereotactic ablative radiotherapy (SART) for medically inoperable stage-I/II non-small-cell lung cancers.MethodsCAFs were isolated from lung tumour specimens from 16 donors. Initially, intrinsic radiosensitivity was evaluated by checking viability and extent of DNA-damage response (DDR) at different radiation doses. The migrative and invasive capacities of CAFs were thereafter determined after a sub-lethal single radiation dose of 18 Gy. To ascertain the mechanisms behind the altered invasive capacity of cells, expression of matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs) were measured in the conditioned media several days post-irradiation, along with expression of cell surface integrins and dynamics of focal contacts by vinculin-staining.ResultsExposing CAFs to 1 × 18 Gy resulted in a potent induction of multiple nuclear DDR foci (> 9/cell) with little resolution after 120 h, induced premature cellular senescence and inhibition of the proliferative, migrative and invasive capacity. AIR promoted MMP-3 and inhibited MMP-1 appearance to some extent, but did not affect expression of other major MMPs. Furthermore, surface expression of integrins α2, β1 and α5 was consistently enhanced, and a dramatic augmentation and redistribution of focal contacts was observed.ConclusionsOur data indicate that ablative doses of radiation exert advantageous inhibitory effects on the proliferative, migratory and invasive capacity of lung CAFs. The reduced motility of irradiated CAFs might be a consequence of stabilized focal contacts via integrins.
Background Longitudinal biomonitoring studies can provide unique information on how human concentrations change over time, but have so far not been conducted for per-and polyfluoroalkyl substances (PFASs) in a background exposed population. Objectives Determine: i) serum PFAS time trends on an individual level; ii) relative compositions and correlations between different PFASs; and iii) assess selected PFAS concentrations with respect to periodic (calendar year), age and birth cohort (APC) effects. Methods
Total 25(OH)D, health condition, race, and DBP haplotype affected free 25(OH)D, but only health conditions and BMI affected relationships between total and free 25(OH)D. Clinical importance of free 25(OH)D needs to be established in studies assessing outcomes.
In the context of radiotherapy, collateral effects of ablative doses of ionizing radiation (AIR) on stromal components of tumors remains understudied. In this work, cancer-associated fibroblasts (CAFs) isolated from freshly resected human lung tumors were exposed to AIR (1x 18 Gy) and analyzed for their release of paracrine factors. Inflammatory mediators and regulators of angiogenesis and tumor growth were analyzed by multiplex protein assays in conditioned medium (CM) from irradiated and non-irradiated CAFs. Additionally, the profile of secreted proteins was examined by proteomics. In functional assays, effects of CAF-CM on proliferative and migratory capacity of lung tumor cells (H-520/H-522) and human umbilical vein endothelial cells (HUVECs) and their tube-forming capacity were assessed. Our data show that exposure of CAFs to AIR results in 1) downregulated release of angiogenic molecules such as stromal cell-derived factor-1, angiopoietin, and thrombospondin-2 (TSP-2); 2) upregulated release of basic fibroblast growth factor from most donors; and 3) unaffected expression levels of hepatocyte growth factor, interleukin-6 (IL-6), IL-8, IL-1β, and tumor necrosis factor-α. CM from irradiated and control CAFs did not affect differently the proliferative or migratory capacity of tumor cells (H-520/H-522), whereas migratory capacity of HUVECs was partially reduced in the presence of irradiated CAF-CM. Overall, we conclude that AIR mediates a transformation on the secretory profile of CAFs that could influence the behavior of other cells in the tumor tissue and hence guide therapeutic outcomes. Downstream consequences of the changes observed in this study merits further investigations.
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