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Objective Studying the biology of the human placenta represents a major experimental challenge. Although conventional cell culture techniques have been used to study different types of placenta-derived cells, current in vitro models have limitations in recapitulating organ-specific structure and key physiological functions of the placenta. Here we demonstrate that it is possible to leverage microfluidic and microfabrication technologies to develop a microengineered biomimetic model that replicates the architecture and function of the placenta. Materials and methods A “Placenta-on-a-Chip” microdevice was created by using a set of soft elastomer-based microfabrication techniques known as soft lithography. This microsystem consisted of two polydimethylsiloxane (PDMS) microfluidic channels separated by a thin extracellular matrix (ECM) membrane. To reproduce the placental barrier in this model, human trophoblasts (JEG-3) and human umbilical vein endothelial cells (HUVECs) were seeded onto the opposite sides of the ECM membrane and cultured under dynamic flow conditions to form confluent epithelial and endothelial layers in close apposition. We tested the physiological function of the microengineered placental barrier by measuring glucose transport across the trophoblast-endothelial interface over time. The permeability of the barrier study was analyzed and compared to that obtained from acellular devices and additional control groups that contained epithelial or endothelial layers alone. Results Our microfluidic cell culture system provided a tightly controlled fluidic environment conducive to the proliferation and maintenance of JEG-3 trophoblasts and HUVECs on the ECM scaffold. Prolonged culture in this model produced confluent cellular monolayers on the intervening membrane that together formed the placental barrier. This in vivo-like microarchitecture was also critical for creating a physiologically relevant effective barrier to glucose transport. Quantitative investigation of barrier function was conducted by calculating permeability coefficients and metabolic rates in varying conditions of barrier structure. The rates of glucose transport and metabolism were consistent with previously reported in vivo observations. Conclusion The “Placenta-on-a-Chip” microdevice described herein provides new opportunities to simulate and analyze critical physiological responses of the placental barrier. This system may be used to address the major limitations of existing placenta model systems and serve to enable research platforms for reproductive biology and medicine.

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The majority of mammalian cells have nonmotile primary cilia on their surface that act as antenna-like sensory organelles. Genetic defects that result in ciliary dysfunction are associated with obesity in humans and rodents, which suggests that functional cilia are important for controlling energy balance. Here we demonstrated that neuronal cilia lengths were selectively reduced in hypothalami of obese mice with leptin deficiency and leptin resistance. Treatment of N1 hypothalamic neuron cells with leptin stimulated cilia assembly via inhibition of the tumor suppressors PTEN and glycogen synthase kinase 3β (GSK3β). Induction of short cilia in the hypothalamus of adult mice increased food intake and decreased energy expenditure, leading to a positive energy balance. Moreover, mice with short hypothalamic cilia exhibited attenuated anorectic responses to leptin, insulin, and glucose, which indicates that leptin-induced cilia assembly is essential for sensing these satiety signals by hypothalamic neurons. These data suggest that leptin governs the sensitivity of hypothalamic neurons to metabolic signals by controlling the length of the cell's antenna. IntroductionMost mammalian cells have single nonmotile primary cilia, which were once thought to be vestigial but are now considered to be important signaling centers (1, 2). Accumulating evidence suggests a strong association between genetic ciliopathies and obesity in humans and animals (3). Obesity is a common manifestation observed in human genetic ciliopathies such as Bardet-Biedl syndrome (BBS) and Alström syndrome (4). Mice that lack BBS proteins and ciliary proteins such as the kinesin-2 subunit KIF3A and the intraflagellar transport protein 88 homolog (IFT88) are obese and hyperphagic (5-7). Furthermore, selective depletion of KIF3A in neurons, particularly in anorexigenic proopiomelanocortinproducing (POMC-producing) neurons, yields an obese phenotype (7), which suggests that neuronal cilia play a critical role in the maintenance of energy balance. Based on the association between genetic ciliopathies and obesity (3), we hypothesized that acquired or other types of genetic obesity may accompany ciliary defects in the hypothalamus, a key brain area involved in the sensation of peripheral metabolic signals and the orchestration of whole-body energy metabolism.

Galectin-1 is an anti-inflammatory lectin with pleiotropic regulatory functions at the crossroads of innate and adaptive immunity. It is expressed in immune privileged sites and is implicated in establishing maternal-fetal immune tolerance, which is essential for successful pregnancy in eutherian mammals. Here, we show conserved placental localization of galectin-1 in primates and its predominant expression in maternal decidua. Phylogenetic footprinting and shadowing unveil conserved cis motifs, including an estrogen responsive element in the 5 promoter of LGALS1, that were gained during the emergence of placental mammals and could account for sex steroid regulation of LGALS1 expression, thus providing additional evidence for the role of galectin-1 in immuneendocrine cross-talk. Maximum parsimony and maximum likelihood analyses of 27 publicly available vertebrate and seven newly sequenced primate LGALS1 coding sequences reveal that intense purifying selection has been acting on residues in the carbohydrate recognition domain and dimerization interface that are involved in immune functions. Parsimony-and codon model-based phylogenetic analysis of coding sequences show that amino acid replacements occurred in early mammalian evolution on key residues, including gain of cysteines, which regulate immune functions by redox status-mediated conformational changes that disable sugar binding and dimerization, and that the acquired immunoregulatory functions of galectin-1 then became highly conserved in eutherian lineages, suggesting the emergence of hormonal and redox regulation of galectin-1 in placental mammals may be implicated in maternal-fetal immune tolerance.decidua ͉ estrogen ͉ glycocode ͉ immune-endocrine cross-talk ͉ pregnancy T he success of mammalian pregnancy, in which the developing fetus and mother exchange nutrients, gases, and other molecules via the chorioallantoic placenta, requires maternal immune tolerance to fetal allo-antigens (1-4). This tolerance presumably prevents the occurrence of exaggerated inflammation at the implantation site and reduces the danger of destructive immune attacks on the fetus, a danger that the first mammals with an invasive placenta would have faced (5, 6). It seems likely that mechanisms for immune tolerance to invasive placentation were already functioning in the early placental mammals and that immunoregulatory molecules, which had existed before the mammalian placenta evolved, were incorporated in this tolerance and have undergone evolutionary modifications coincident with the emergence of the mammalian placenta. Here, we present evidence that such modifications occurred in a key immunoregulatory molecule, galectin-1.Molecules that have been implicated in conferring maternalfetal immune tolerance include galectin-1, B7 proteins, Crry, Fas ligand, HLA-G, indoleamine 2,3-dioxygenase, and killer cell immunoglobulin-like receptors (2-4, 7-11). These proteins are involved in pathways regulating adaptive or innate immune responses at the maternal-fetal interface, and their di...

The amnion plays an important role during pregnancy and parturition. Though referred to as a single structure, this fetal tissue is regionally divided into placental amnion, reflected amnion, and umbilical amnion. Histological differences between placental amnion and reflected amnion led us to hypothesize that the amnion is biologically heterogeneous. The gene expression profiles of placental amnion and reflected amnion were compared in patients at term with no labor (TNL; n = 10) and in labor (TIL; n = 10). Real-time quantitative RT-PCR revealed a higher expression of IL1B mRNA in reflected amnion than in placental amnion in TNL cases but not in TIL cases. Extended screening using microarrays showed differential expression of 17 genes in labor, regardless of the region. Interestingly, 839 genes were differentially expressed between placental amnion and reflected amnion. Pathway analysis identified 19 signaling pathways, such as mitogen-activated protein kinase and transforming growth factor beta pathways, associated with region. Lipopolysaccharide (LPS) treatment of the amnion explants showed more robust activation of mitogen-activated protein kinase 3/1 (extracellular signal-regulated kinase 1/2) in placental amnion of TNL but not in TIL cases. Placental amnion from TNL and TIL cases showed a significant difference in the amplitude of IL1B mRNA induction by LPS. We report that the anatomical region has a substantial impact on the transcriptional program and the biological properties of the amnion. Labor-associated switching to a proinflammatory signature is a feature particular to placental amnion. The novel observations herein strongly suggest that the seemingly homogeneous amnion is biologically heterogeneous and compartmentalized, with implications for the physiology of pregnancy and parturition.

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Background/AimsThe different clinical manifestations of gastroesophageal reflux disease (GERD) may be influenced by associated psychological factors. We evaluated the psychological status (anxiety and depression) according to each subtype of GERD.MethodsSubjects who underwent esophagogastroduodenoscopy and completed a symptom questionnaire between January 2008 and December 2011 were analyzed. The subjects were classified into the following groups: erosive reflux disease (ERD), non-erosive reflux disease (NERD), asymptomatic erosive esophagitis (AEE), and controls. Anxiety and depression were assessed using the State-Trait Anxiety Inventory and Beck Depression Inventory, respectively.ResultsWe analyzed 19 099 subjects: 16 157 (84.6%), 176 (0.9%), 1398 (7.3%), and 1368 (7.2%) in the control, ERD, NERD, and AEE groups, respectively. Multiple multinomial logistic regression revealed a significant association of increased state (adjusted OR, 1.89; 95% CI, 1.53–2.33) and trait anxiety (adjusted OR, 1.78; 95% CI, 1.34–2.35) and depression (adjusted OR, 2.21; 95% CI, 1.75–2.80) with NERD. ERD group showed a significant association only with state anxiety (adjusted OR, 2.20; 95% CI, 1.27–3.81) and depression (adjusted OR, 2.23; 95% CI, 1.18–4.22). The AEE group, however, did not show any significant association with psychological factors.ConclusionThis cross-sectional study revealed that anxiety and depression levels were significantly higher in subjects with GERD (notably in the NERD) than in controls.