Labor resembles an inflammatory response that includes secretion of cytokines/chemokines by resident and infiltrating immune cells into reproductive tissues and the maternal/fetal interface. Untimely activation of these inflammatory pathways leads to preterm labor, which can result in preterm birth. Preterm birth is a major determinant of neonatal mortality and morbidity; therefore, the elucidation of the process of labor at a cellular and molecular level is essential for understanding the pathophysiology of preterm labor. Here, we summarize the role of innate and adaptive immune cells in the physiological or pathological activation of labor. We review published literature regarding the role of innate and adaptive immune cells in the cervix, myometrium, fetal membranes, decidua and the fetus in late pregnancy and labor at term and preterm. Accumulating evidence suggests that innate immune cells (neutrophils, macrophages and mast cells) mediate the process of labor by releasing pro-inflammatory factors such as cytokines, chemokines and matrix metalloproteinases. Adaptive immune cells (T-cell subsets and B cells) participate in the maintenance of fetomaternal tolerance during pregnancy, and an alteration in their function or abundance may lead to labor at term or preterm. Also, immune cells that bridge the innate and adaptive immune systems (natural killer T (NKT) cells and dendritic cells (DCs)) seem to participate in the pathophysiology of preterm labor. In conclusion, a balance between innate and adaptive immune cells is required in order to sustain pregnancy; an alteration of this balance will lead to labor at term or preterm.

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Species differ greatly in their rates of aging. Among mammalian species life span ranges from 2 to over 60 years. Here, we test the hypothesis that skin-derived fibroblasts from long-lived species of animals differ from those of short-lived animals in their defenses against protein damage. In parallel studies of rodents, nonhuman primates, birds, and species from the Laurasiatheria superorder (bats, carnivores, shrews, and ungulates), we find associations between species longevity and resistance of proteins to oxidative stress after exposure to H(2)O(2) or paraquat. In addition, baseline levels of protein carbonyl appear to be higher in cells from shorter-lived mammals compared with longer-lived mammals. Thus, resistance to protein oxidation is associated with species maximal life span in independent clades of mammals, suggesting that this cellular property may be required for evolution of longevity. Evaluation of the properties of primary fibroblast cell lines can provide insights into the factors that regulate the pace of aging across species of mammals.

SummaryIn a survey of enzymes related to protein oxidation and cellular redox state, we found activity of the redox enzyme thioredoxin reductase (TXNRD) to be elevated in cells from long‐lived species of rodents, primates, and birds. Elevated TXNRD activity in long‐lived species reflected increases in the mitochondrial form, TXNRD2, rather than the cytosolic forms TXNRD1 and TXNRD3. Analysis of published RNA‐Seq data showed elevated TXNRD2 mRNA in multiple organs of longer‐lived primates, suggesting that the phenomenon is not limited to skin‐derived fibroblasts. Elevation of TXNRD2 activity and protein levels was also noted in liver of three different long‐lived mutant mice, and in normal male mice treated with a drug that extends lifespan in males. Overexpression of mitochondrial TXNRD2 in Drosophila melanogaster extended median (but not maximum) lifespan in female flies with a small lifespan extension in males; in contrast, overexpression of the cytosolic form, TXNRD1, did not produce a lifespan extension.

Introduction: Previous studies have reported inverse associations of circulating and tissue levels of pentadecanoic acid (15:0), heptadecanoic acid (17:0) and trans -palmitoleic acid ( trans 16:1n-7), which have been proposed as potential biomarkers of dairy fat intake, with risk of type-2 diabetes and certain cardiovascular outcomes. Hypothesis: We assessed the hypothesis that circulating and tissue levels of 15:0, 17:0, trans 16:1n-7 are inversely associated with risk of incident coronary heart disease (CHD) and stroke in a global consortium of prospective studies. Methods: We used data from 15 prospective cohorts in the Fatty Acids and Outcomes Research Consortium. We included adults (age≥18 years) who were free of cardiovascular diseases and had blood or adipose tissue measurements of 15:0, 17:0 or trans 16:1n-7. We used a harmonized analysis protocol with each exposure standardized to the interquintile range (IQR): difference between the 10 th and 90 th percentiles of each fatty acid to conduct new individual participant-level analyses. We harmonized covariate definitions across studies to include demographic, lifestyle and health variables, and levels of other fatty acids associated with CHD or stroke. We used inverse-variance meta-analysis to calculate the pooled relative risks (RR) and 95% confidence intervals (CI) for each outcome. We also calculated Spearman correlation coefficients between levels of each fatty acid exposure and potential dietary determinants of their levels (intakes of total, high-fat and low-fat dairy, meat from ruminant animals, fish and dietary fiber) among 6 studies with dietary data. Results and Conclusions: Among 34,187 participants, 5,790 incident CHD and 3,098 stroke cases were documented during a maximum follow-up of 23.3 years. We did not observe significant associations of any of the fatty acid biomarkers with risk of CHD or stroke. The pooled multivariate RR and 95% CI of CHD per IQR were 0.97 (0.92, 1.02) for 15:0, 0.97 (0.92, 1.02) for 17:0, 1.11 (0.97, 1.26) for trans 16:1n-7, and 0.98 (0.92, 1.04) for the sum of the fatty acids. The respective RR and 95% of stroke were 1.01 (0.93, 1.09) for 15:0, 0.91 (0.81, 1.03) for 17:0, 0.99 (0.83, 1.18) for trans 16:1n-7, and 0.93 (0.85, 1.04) for the summed fatty acids. Additionally, we did not observe significant heterogeneity by age, sex, race/ethnicity, world region, baseline hypertension status or lipid compartment. Circulating and tissue levels of 15:0, 17:0 and trans 16:1n-7 were weakly correlated with intakes of total or high-fat dairy (Spearman correlations [ r = 0.05 to 0.37]) but were not correlated with intakes of low-fat dairy, ruminant meat, fish or dietary fiber [ r = -0.08 to 0.09]. In conclusion, circulating and tissue levels of 15:0, 17:0, trans 16:1n-7 were not associated with risk of CHD or stroke. Our study suggests a limited role for these fatty acids in the etiology of cardiovascular disease.

Objective: Endotoxin treatment causes preterm delivery in mice, and this is associated with an expansion of regulatory T cells (Tregs) in primary lymphoid organs (Arenas-Hernandez et al. unpublished data). Our aim was to determine whether this expansion causes a pro-inflammatory state and/or macrophage M2-M1 polarization at the maternal-fetal interface. Methods: Pregnant C57BL/6 mice were injected with either 15 μg of LPS (E. coli 0111:B4) or 200 μl PBS as a control (n=9-11 each). Mice were euthanized just prior to preterm delivery. Uterine and decidual cell suspensions were prepared and analyzed by flow cytometry to identify CD4+ and CD8+ Tregs, Th9 cells, Th17 cells, T-bet+ T cells, neutrophils, macrophages, IL4- and IFNγ-producing T cells, and M1 and M2 macrophages. Results: 1) Uterine, but not decidual, CD4+ Tregs were fewer in LPS treated mice than in controls (p=0.019); 2) Uterine and decidual macrophages were fewer in LPS treated mice than in controls (p=0.025 and 0.036); 3) Uterine and decidual neutrophils were greater in LPS treated mice than in controls (p=0.002 and 0.0001); 4) Decidual IFNγ-producing T cells were fewer in LPS treated mice than in controls (p=0.036); 5) M1 and M2 macrophage populations did not change with LPS treatment. Conclusions: Endotoxin treatment of pregnant mice promotes a pro-inflammatory stage, which includes abundant neutrophils and scarce regulatory T cells and macrophages (M1 and M2) at the maternal-fetal interface.