Temporal trends in microplastic accumulation in placentas from pregnancies in Hawai'i.

Microplastics are created for commercial use, are shed from textiles, or result from the breakdown of larger plastic items. Recent reports have shown that microplastics accumulate in human tissues and may have adverse health consequences. Currently, there are no standardized environmental monitoring systems to track microplastic accumulation within human tissues. Using Raman spectroscopy, we investigated the temporal exposures to plastic pollution in Hawai'i and noted a significant increase in the accumulation of microplastics in discarded placentas over the past 15 years, with changes in the size and chemical composition of the polymers. These findings provide a rare insight into the vulnerability and sensitivity of Pacific Island residents to plastic pollution and illustrate how discarded human tissues can be used as an innovative environmental plastic pollution monitoring system.

Exosome-Enriched Plasma Analysis as a Tool for the Early Detection of Hypertensive Gestations.

Hypertensive disorders of pregnancy are closely associated with prematurity, stillbirth, and maternal morbidity and mortality. The onset of hypertensive disorders of pregnancy (HDP) is generally noticed after the 20th week of gestation, limiting earlier intervention. The placenta is directly responsible for modulating local and systemic physiology by communicating using mechanisms such as the release of extracellular vesicles, especially exosomes. In this study, we postulated that an analysis of exosome-enriched maternal plasma could provide a more focused and applicable approach for diagnosing HDP earlier in pregnancy. Therefore, the peripheral blood plasma of 24 pregnant women (11 controls, 13 HDP) was collected between 20th and 24th gestational weeks and centrifuged for exosome enrichment. Exosome-enriched plasma samples were analyzed by Raman spectroscopy and by proton nuclear magnetic resonance metabolomics (1H NMR). Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to analyze the Raman data, from the spectral region of 600-1,800 cm-1, to determine its potential to discriminate between groups. Using principal component analysis, we were able to differentiate the two groups, with 89% of all variances found in the first three principal components. In patients with HDP, most significant differences in Raman bands intensity were found for sphingomyelin, acetyl CoA, methionine, DNA, RNA, phenylalanine, tryptophan, carotenoids, tyrosine, arginine, leucine, amide I and III, and phospholipids. The 1H NMR analysis showed reduced levels of D-glucose, L-proline, L-tyrosine, glycine, and anserine in HDP, while levels of 2-hydroxyvalerate, polyunsaturated fatty acids, and very-low-density lipoprotein (VLDL) were increased. 1H NMR results were able to assign an unknown sample to either the control or HDP groups at a precision of 88.3% using orthogonal partial least squares discriminant analysis and 87% using logistic regression analysis. Our results suggested that an analysis of exosome-enriched plasma could provide an initial assessment of placental function at the maternal-fetal interface and aid HDP diagnosis, prognosis, and treatment, as well as to detect novel, early biomarkers for HDP.

Chemokine (C-C motif) ligand 25 expressed by trophoblast cells and leukocytes bearing its receptor Ccr9: An alliance during embryo implantation?

PROBLEM: We hypothesized that trophoblast expression of Ccl25 attracts a specific leukocyte cell population to the implantation site for local regulation. METHOD OF STUDY: Mice blastocysts, ectoplacental cones, and decidua at gestational days 3.5-7.5 were evaluated for Ccl25 and Ccr9 expressions. Peripheral availability and characterization of Ccr9+ leukocytes were determined by flow cytometry. Leukocyte chemotaxis was assessed in the presence of Ccl25 recombinant protein and embryos using antisense oligomers (ODNs) to Ccl25 and Ccr9 neutralizing antibody. RESULTS: Ccl25 was expressed by embryonic cells, whereas Ccr9 expression was strong at the maternal compartment and in PBMC. Immunolocalization confirmed this expression. In vitro, chemotaxis assays showed that the embryonic Ccl25 signals to Ccr9+ PBMCs. Maternal Ccr9+α4ß7+ monocytes switch from an anti-inflammatory phenotype (F4/80+11b+Ly6C-TGF-ß+ cells, pre-implantation) to an inflammatory profile (F4/80+11b+Ly6C+TNF-α+ cells, post-implantation). CONCLUSION: Our data support the establishment of a CCL25/CCR9-axis at the maternal-fetal interface in mice, which may be involved in immune regulatory mechanisms during embryo implantation.