The Impact of Abnormal Lipid Metabolism on the Occurrence Risk of Idiopathic Pulmonary Arterial Hypertension.

The aim was to determine whether lipid molecules can be used as potential biomarkers for idiopathic pulmonary arterial hypertension (IPAH), providing important reference value for early diagnosis and treatment. Liquid chromatography-mass spectrometry-based lipidomic assays allow for the simultaneous detection of a large number of lipids. In this study, lipid profiling was performed on plasma samples from 69 IPAH patients and 30 healthy controls to compare the levels of lipid molecules in the 2 groups of patients, and Cox regression analysis was used to identify meaningful metrics, along with receiver operator characteristic curves to assess the ability of the lipid molecules to predict the risk of disease in patients. Among the 14 lipid subclasses tested, 12 lipid levels were significantly higher in IPAH patients than in healthy controls. Free fatty acids (FFA) and monoacylglycerol (MAG) were significantly different between IPAH patients and healthy controls. Logistic regression analysis showed that FFA (OR: 1.239, 95%CI: 1.101, 1.394, p < 0.0001) and MAG (OR: 3.711, 95%CI: 2.214, 6.221, p < 0.001) were independent predictors of IPAH development. Among the lipid subclasses, FFA and MAG have potential as biomarkers for predicting the pathogenesis of IPAH, which may improve the early diagnosis of IPAH.

The Placental NLRP3 Inflammasome and Its Downstream Targets, Caspase-1 and Interleukin-6, Are Increased in Human Fetal Growth Restriction: Implications for Aberrant Inflammation-Induced Trophoblast Dysfunction.

Fetal growth restriction (FGR) is commonly associated with placental insufficiency and inflammation. Nonetheless, the role played by inflammasomes in the pathogenesis of FGR is poorly understood. We hypothesised that placental inflammasomes are differentially expressed and contribute to the aberrant trophoblast function. Inflammasome gene expression profiles were characterised by real-time PCR on human placental tissues collected from third trimester FGR and gestation-matched control pregnancies (n = 25/group). The functional significance of a candidate inflammasome was then investigated using lipopolysaccharide (LPS)-induced models of inflammation in human trophoblast organoids, BeWo cells in vitro, and a murine model of FGR in vivo. Placental mRNA expression of NLRP3, caspases 1, 3, and 8, and interleukin 6 increased (>2-fold), while that of the anti-inflammatory cytokine, IL-10, decreased (<2-fold) in FGR compared with control pregnancies. LPS treatment increased NLRP3 and caspase-1 expression (>2-fold) in trophoblast organoids and BeWo cell cultures in vitro, and in the spongiotrophoblast and labyrinth in the murine model of FGR. However, the LPS-induced rise in NLRP3 was attenuated by its siRNA-induced down-regulation in BeWo cell cultures, which correlated with reduced activity of the apoptotic markers, caspase-3 and 8, compared to the control siRNA-treated cells. Our findings support the role of the NLRP3 inflammasome in the inflammation-induced aberrant trophoblast function, which may contribute to FGR.

Mesenchymal Stem/Stromal Cells and Their Role in Oxidative Stress Associated with Preeclampsia.

Preeclampsia (PE) is a serious medically important disorder of human pregnancy, which features de novo pregnancy-induced hypertension and proteinuria. The severe form of PE can progress to eclampsia, a convulsive, life-threatening condition. When placental growth and perfusion are abnormal, the placenta experiences oxidative stress and subsequently secretes abnormal amounts of certain pro-angiogenic factors (eg, PlGF) as well as anti-angiogenic factors (eg, sFlt-1) that enter the maternal circulation. The net effect is damage to the maternal vascular endothelium, which subsequently manifests as the clinical features of PE. Other than delivery of the fetus and placenta, curative treatments for PE have not yet been forthcoming, which reflects the complexity of the clinical syndrome. A major source of reactive oxygen species that contributes to the widespread maternal vascular endothelium damage is the PE-affected decidua. The role of decidua-derived mesenchymal stem/stromal cells (MSC) in normotensive and pathological placenta development is poorly understood. The ability to respond to an environment of oxidative damage is a "universal property" of MSC but the biological mechanisms that MSC employ in response to oxidative stress are compromised in PE. In this review, we discuss how MSC respond to oxidative stress in normotensive and pathological conditions. We also consider the possibility of manipulating the oxidative stress response of abnormal MSC as a therapeutic strategy to treat preeclampsia.

Improvement of Mesenchymal Stromal Cell Proliferation and Differentiation via Decellularized Extracellular Matrix on Substrates With a Range of Surface Chemistries.

Decellularized extracellular matrix (dECM) deposited by mesenchymal stromal cells (MSCs) has emerged as a promising substrate for improved expansion of MSCs. To date, essentially all studies that have produced dECM for MSC expansion have done so on tissue culture plastic or glass. However, substrate surface chemistry has a profound impact on the adsorption of proteins that mediate cell-material interactions, and different surface chemistries can cause changes in cell behavior, ECM deposition, and the in vivo response to a material. This study tested the hypothesis that substrate surface chemistry impacts the deposition of ECM and its subsequent bioactivity. This hypothesis was tested by producing glass surfaces with various surface chemistries (amine, carboxylic acid, propyl, and octyl groups) using silane chemistry. ECM was deposited by an immortalized MSC line, decellularized, and characterized through SDS-PAGE and immunofluorescence microscopy. No significant difference was observed in dECM composition or microarchitecture on the different surfaces. The decellularized surfaces were seeded with primary MSCs and their proliferation and differentiation were assessed. The presence of dECM improved the proliferation of primary MSCs by ~100% in comparison to surface chemistry controls. Additionally, the adipogenesis increased by 50-90% on all dECM surfaces in comparison to surface chemistry controls, and the osteogenesis increased by ~50% on the octyl-modified surfaces when dECM was present. However, no statistically significant differences were observed within the set of dECM surfaces or control surfaces. These results support the null hypothesis, meaning surface chemistry (over the range tested in this work) is not a key regulator of the composition or bioactivity of MSC-derived dECM. These results are significant because they provide an important insight into regenerative engineering technologies. Specifically, the utilization of dECM in stem cell manufacturing and tissue engineering applications would require the dECM to be produced on a wide variety of substrates. This work indicates that it can be produced on materials with a range of surface chemistries without undesired changes in the bioactivity of the dECM.

HMGB1 plays an important role in pyroptosis induced blood brain barrier breakdown in diabetes-associated cognitive decline.

Diabetes mellitus increases the risk of dementia, and evidence suggests hyperglycemia is a key contributor to neurodegeneration. However, our understanding of diabetes-associated cognitive decline, an important complication of diabetes mellitus, is lacking and the underlying mechanism is unclear. Blood brain barrier (BBB) breakdown is a possible cause of dementia in diabetes mellitus and Alzheimer's disease. Accumulating evidence shows BBB dysfunction caused by hyperglycemia contributes to cognitive decline. A specific type of inflammatory programmed cell death, called pyroptosis, has potential as a therapeutic target for BBB-associated diseases. Potential inducers of pyroptosis include inflammasomes such as NLRP3, whose activation relies on damage-associated molecular patterns. High mobility group box 1 (HMGB1) is a highly conserved, ubiquitous protein found in most cell types, and acts as a damage-associated molecular pattern when released from the nucleus. We propose that HMGB1 influences vascular inflammation by activating the NLRP3 inflammasome and thereby initiating pyroptosis in vascular cells. Moreover, HMGB1 plays a pivotal role in the pathogenesis of diabetes mellitus and diabetic complications. Here, we review the role of HMGB1 in BBB dysfunction induced by hyperglycemia and propose that HMGB1 is a promising therapeutic target for countering diabetes-associated cognitive decline.

Extracellular-Vesicle-Based Coatings Enhance Bioactivity of Titanium Implants-SurfEV.

Extracellular vesicles (EVs) are nanoparticles released by cells that contain a multitude of biomolecules, which act synergistically to signal multiple cell types. EVs are ideal candidates for promoting tissue growth and regeneration. The tissue regenerative potential of EVs raises the tantalizing possibility that immobilizing EVs on implant surfaces could potentially generate highly bioactive and cell-instructive surfaces that would enhance implant integration into the body. Such surfaces could address a critical limitation of current implants, which do not promote bone tissue formation or bond bone. Here, we developed bioactive titanium surface coatings (SurfEV) using two types of EVs: secreted by decidual mesenchymal stem cells (DEVs) and isolated from fermented papaya fluid (PEVs). For each EV type, we determined the size, morphology, and molecular composition. High concentrations of DEVs enhanced cell proliferation, wound closure, and migration distance of osteoblasts. In contrast, the cell proliferation and wound closure decreased with increasing concentration of PEVs. DEVs enhanced Ca/P deposition on the titanium surface, which suggests improvement in bone bonding ability of the implant (i.e., osteointegration). EVs also increased production of Ca and P by osteoblasts and promoted the deposition of mineral phase, which suggests EVs play key roles in cell mineralization. We also found that DEVs stimulated the secretion of secondary EVs observed by the presence of protruding structures on the cell membrane. We concluded that, by functionalizing implant surfaces with specialized EVs, we will be able to enhance implant osteointegration by improving hydroxyapatite formation directly at the surface and potentially circumvent aseptic loosening of implants.

New Multiscale Characterization Methodology for Effective Determination of Isolation-Structure-Function Relationship of Extracellular Vesicles.

Extracellular vesicles (EVs) have been lauded as next-generation medicines, but very few EV-based therapeutics have progressed to clinical use. Limited clinical translation is largely due to technical barriers that hamper our ability to mass produce EVs, i.e., to isolate, purify, and characterize them effectively. Technical limitations in comprehensive characterization of EVs lead to unpredicted biological effects of EVs. Here, using a range of optical and non-optical techniques, we showed that the differences in molecular composition of EVs isolated using two isolation methods correlated with the differences in their biological function. Our results demonstrated that the isolation method determines the composition of isolated EVs at single and sub-population levels. Besides the composition, we measured for the first time the dry mass and predicted sedimentation of EVs. These parameters were likely to contribute to the biological and functional effects of EVs on single cell and cell cultures. We anticipate that our new multiscale characterization approach, which goes beyond traditional experimental methodology, will support fundamental understanding of EVs as well as elucidate the functional effects of EVs in in vitro and in vivo studies. Our findings and methodology will be pivotal for developing optimal isolation methods and establishing EVs as mainstream therapeutics and diagnostics. This innovative approach is applicable to a wide range of sectors including biopharma and biotechnology as well as to regulatory agencies.

Late/post-term decidual basalis-derived mesenchymal stem/stromal cells show evidence of advanced ageing and downregulation of microRNA-516b-5p.

INTRODUCTION: The placenta is a short-lived organ, yet it shows signs of progressive ageing in the third trimester. Studies of ageing chorionic placental tissue have recently flourished, providing evidence of advanced ageing of tissues in the late/post-term (L/PT) period of gestation. However, ageing of the maternal aspect of the maternal-fetal interface, specifically the decidua basalis, is poorly understood. Here, we investigated whether the L/PT period was associated with advanced ageing and exhaustion of important decidua basalis mesenchymal stem/stromal cells (DMSCs) functions. METHODS: In this study, DMSCs were isolated and characterised from early term (ET) and L/PT placental tissue and they were then investigated by employing various MSC potency and ageing assays. RNA sequencing was also performed to screen for specific microRNAs that are associated with stem cell exhaustion and ageing between ET- and L/PT-DMSCs. RESULTS: L/PT-DMSCs, when compared to ET-DMSCs, showed significantly lower cell proliferation and a significant higher level of cell apoptosis. L/PT-DMSCs showed significantly lower resistance to oxidative stress and a significant decrease in antioxidant capacity compared with ET-DMSCs. Western blot analysis revealed increased expression of the stress-mediated P-p38MAPK protein in L/PT-DMSCs. RNA Sequencing showed microRNA (miR) miR-516b-5p, was present at significantly lower levels in L/PT-DMSCs. Inhibition of miR-516b-5p in ET-DMSCs revealed a decline in the ability of the inhibited cells to survive in extended cell culture. DISCUSSION: These data provide the first evidence of advanced ageing and exhaustion of important stem cell functions in L/PT-DMSCs, and the involvement of specific miRs in the DMSC ageing process.

The Emerging Role of the Prokineticins and Homeobox Genes in the Vascularization of the Placenta: Physiological and Pathological Aspects.

Vasculogenesis and angiogenesis are key processes of placental development, which occur throughout pregnancy. Placental vasculogenesis occurs during the first trimester of pregnancy culminating in the formation of hemangioblasts from intra-villous stem cells. Placental angiogenesis occurs subsequently, forming new blood vessels from existing ones. Angiogenesis also takes place at the fetomaternal interface, allowing essential spiral arteriole remodeling to establish the fetomaternal circulation. Vasculogenesis and angiogenesis in animal models and in humans have been studied in a wide variety of in vitro, physiological and pathological conditions, with a focus on the pro- and anti-angiogenic factors that control these processes. Recent studies revealed roles for new families of proteins, including direct participants such as the prokineticin family, and regulators of these processes such as the homeobox genes. This review summarizes recent advances in understanding the molecular mechanisms of actions of these families of proteins. Over the past decade, evidence suggests increased production of placental anti-angiogenic factors, as well as angiogenic factors are associated with fetal growth restriction (FGR) and preeclampsia (PE): the most threatening pathologies of human pregnancy with systemic vascular dysfunction. This review also reports novel clinical strategies targeting members of these family of proteins to treat PE and its consequent effects on the maternal vascular system.

Decidual mesenchymal stem/stromal cell-derived extracellular vesicles ameliorate endothelial cell proliferation, inflammation, and oxidative stress in a cell culture model of preeclampsia.

Oxidative stress and endothelial dysfunction contribute substantially to the pathogenesis of preeclampsia (PE). Decidual mesenchymal stem/stromal cells (DMSC), reportedly reduce endothelial cell dysfunction and alleviate PE-like symptoms in a murine model. However, as a therapeutic strategy, the use of whole DMSC presents significant technical limitations, which may be overcome by employing DMSC-secreted extracellular vesicles (DMSC_EV). DMSC_EV restoration of endothelial dysfunction through a paracrine effect may alleviate the clinical features of PE. OBJECTIVE: To determine whether DMSC-secreted, extracellular vesicles (DMSC_EV) restore endothelial cell function and reduce oxidative stress. METHODS: DMSC were isolated from the placentae of uncomplicated term pregnancies and DMSC_EV prepared by ultracentrifugation. Human umbilical vein endothelial cells (HUVEC) were treated with bacterial lipopolysaccharide (LPS), or with serum from PE patients, to model the effects of PE. DMSC_EV were then added to treated HUVEC and their growth profiles, inflammatory state, and oxidative stress levels measured. RESULTS: DMSC_EV displayed characteristic features of extracellular vesicles. In both LPS- and PE serum-treatment models, addition of DMSC_EV significantly increased HUVEC cell attachment and proliferation, and significantly reduced production of pro-inflammatory cytokine IL-6. The addition of DMSC_EV to LPS-treated HUVEC had no significant effect on total antioxidant capacity, superoxide dismutase levels or on lipid peroxidation levels. In contrast, the addition of DMSC_EV to PE serum-treated HUVEC resulted in a significant reduction in levels of lipid peroxidation. CONCLUSION: Addition of DMSC_EV had beneficial effects in both LPS- and PE serum- treated HUVEC but the two treatment models to induce endothelial cell dysfunction showed differences. The LPS treatment of HUVEC model may not accurately model the endothelial cell dysfunction characteristic of PE. Human cell culture models of PE show that DMSC_EV improve endothelial cell dysfunction in PE, but testing in in vivo models of PE is required.

Innate immune responses to malaria-infected erythrocytes in pregnant women: Effects of gravidity, malaria infection, and geographic location.

BACKGROUND: Malaria in pregnancy causes maternal, fetal and neonatal morbidity and mortality, and maternal innate immune responses are implicated in pathogenesis of these complications. The effects of malaria exposure and obstetric and demographic factors on the early maternal immune response are poorly understood. METHODS: Peripheral blood mononuclear cell responses to Plasmodium falciparum-infected erythrocytes and phytohemagglutinin were compared between pregnant women from Papua New Guinea (malaria-exposed) with and without current malaria infection and from Australia (unexposed). Elicited levels of inflammatory cytokines at 48 h and 24 h (interferon γ, IFN-γ only) and the cellular sources of IFN-γ were analysed. RESULTS: Among Papua New Guinean women, microscopic malaria at enrolment did not alter peripheral blood mononuclear cell responses. Compared to samples from Australia, cells from Papua New Guinean women secreted more inflammatory cytokines tumor necrosis factor-α, interleukin 1ß, interleukin 6 and IFN-γ; p<0.001 for all assays, and more natural killer cells produced IFN-γ in response to infected erythrocytes and phytohemagglutinin. In both populations, cytokine responses were not affected by gravidity, except that in the Papua New Guinean cohort multigravid women had higher IFN-γ secretion at 24 h (p = 0.029) and an increased proportion of IFN-γ+ Vδ2 γδ T cells (p = 0.003). Cytokine levels elicited by a pregnancy malaria-specific CSA binding parasite line, CS2, were broadly similar to those elicited by CD36-binding line P6A1. CONCLUSIONS: Geographic location and, to some extent, gravidity influence maternal innate immunity to malaria.

Functional changes in decidual mesenchymal stem/stromal cells are associated with spontaneous onset of labour.

Ageing and parturition share common pathways, but their relationship remains poorly understood. Decidual cells undergo ageing as parturition approaches term, and these age-related changes may trigger labour. Mesenchymal stem/stromal cells (MSCs) are the predominant stem cell type in the decidua. Stem cell exhaustion is a hallmark of ageing, and thus ageing of decidual MSCs (DMSCs) may contribute to the functional changes in decidual tissue required for term spontaneous labour. Here, we determine whether DMSCs from patients undergoing spontaneous onset of labour (SOL-DMSCs) show evidence of ageing-related functional changes compared with those from patients not in labour (NIL-DMSCs), undergoing Caesarean section. Placentae were collected from term (37-40 weeks of gestation), SOL (n = 18) and NIL (n = 17) healthy patients. DMSCs were isolated from the decidua basalis that remained attached to the placenta after delivery. DMSCs displayed stem cell-like properties and were of maternal origin. Important cell properties and lipid profiles were assessed and compared between SOL- and NIL-DMSCs. SOL-DMSCs showed reduced proliferation and increased lipid peroxidation, migration, necrosis, mitochondrial apoptosis, IL-6 production and p38 MAPK levels compared with NIL-DMSCs (P < 0.05). SOL- and NIL-DMSCs also showed significant differences in lipid profiles in various phospholipids (phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylserine), sphingolipids (ceramide, sphingomyelin), triglycerides and acyl carnitine (P < 0.05). Overall, SOL-DMSCs had altered lipid profiles compared with NIL-DMSCs. In conclusion, SOL-DMSCs showed evidence of ageing-related reduced functionality, accumulation of cellular damage and changes in lipid profiles compared with NIL-DMSCs. These changes may be associated with term spontaneous labour.

Ageing in human parturition: impetus of the gestation clock in the decidua†.

Despite sharing many common features, the relationship between ageing and parturition remains poorly understood. The decidua is a specialized lining of endometrial tissue, which develops in preparation for pregnancy. The structure and location of the decidua support its role as the physical scaffold for the growing embryo and placenta, and thus, it is vital to sustain pregnancy. Approaching term, the physical support properties of the decidua are naturally weakened to permit parturition. In this review, we hypothesize that the natural weakening of decidual tissue at parturition is promoted by the ageing process. Studies of the ageing-related functional and molecular changes in the decidua at parturition are reviewed and classified using hallmarks of ageing as the framework. The potential roles of decidual mesenchymal stem/stromal cell (DMSC) ageing in labor are also discussed because, although stem cell exhaustion is also a hallmark of ageing, its role in labor is not completely understood. In addition, the potential roles of extracellular vesicles secreted by DMSCs in labor, and their parturition-related miRNAs, are reviewed to gain further insight into this research area. In summary, the literature supports the notion that the decidua ages as the pregnancy progresses, and this may facilitate parturition, suggesting that ageing is the probable impetus of the gestational clocks in the decidua. This conceptual framework was developed to provide a better understanding of the natural ageing process of the decidua during parturition as well as to encourage future studies of the importance of healthy ageing for optimal pregnancy outcomes.

Correction to: Preconditioning of Human Decidua Basalis Mesenchymal Stem/Stromal Cells with Glucose Increased Their Engraftment and Anti-diabetic Properties.

The author would like to correct the names for the below co-authors in the online published article.

Preconditioning of Human Decidua Basalis Mesenchymal Stem/Stromal Cells with Glucose Increased Their Engraftment and Anti-diabetic Properties.

BACKGROUND: Mesenchymal stem/stromal cells (MSCs) from the decidua basalis (DBMSCs) of the human placenta have important functions that make them potential candidates for cellular therapy. Previously, we showed that DBMSC functions do not change significantly in a high oxidative stress environment, which was induced by hydrogen peroxide (H2O2) and immune cells. Here, we studied the consequences of glucose, another oxidative stress inducer, on the phenotypic and functional changes in DBMSCs. METHODS: DBMSCs were exposed to a high level of glucose, and its effect on DBMSC phenotypic and functional properties was determined. DBMSC expression of oxidative stress and immune molecules after exposure to glucose were also identified. RESULTS: Conditioning of DBMSCs with glucose improved their adhesion and invasion. Glucose also increased DBMSC expression of genes with survival, proliferation, migration, invasion, anti-inflammatory, anti-chemoattractant and antimicrobial properties. In addition, DBMSC expression of B7H4, an inhibitor of T cell proliferation was also enhanced by glucose. Interestingly, glucose modulated DBMSC expression of genes involved in insulin secretion and prevention of diabetes. CONCLUSION: These data show the potentially beneficial effects of glucose on DBMSC functions. Preconditioning of DBMSCs with glucose may therefore be a rational strategy for increasing their therapeutic potential by enhancing their engraftment efficiency. In addition, glucose may program DBMSCs into insulin producing cells with ability to counteract inflammation and infection associated with diabetes. However, future in vitro and in vivo studies are essential to investigate the findings of this study further.

Combined Antioxidant, Anti-inflammaging and Mesenchymal Stem Cell Treatment: A Possible Therapeutic Direction in Elderly Patients with Chronic Obstructive Pulmonary Disease.

Chronic Obstructive Pulmonary Disease (COPD) is a worldwide health problem associated with high morbidity and mortality, especially in elderly patients. Aging functions include mitochondrial dysfunction, cell-to-cell information exchange, protein homeostasis and extracellular matrix dysregulation, which are closely related to chronic inflammatory response and oxidation-antioxidant imbalance in the pathogenesis of COPD. COPD displays distinct inflammaging features, including increased cellular senescence and oxidative stress, stem cell exhaustion, alterations in the extracellular matrix, reduced levels of endogenous anti-inflammaging molecules, and reduced autophagy. Given that COPD and inflammaging share similar general features, it is very important to identify the specific mechanisms of inflammaging, which involve oxidative stress, inflammation and lung mesenchymal stem cell function in the development of COPD, especially in elderly COPD patients. In this review, we highlight the studies relevant to COPD progression, and focus on mechanisms associated with inflammaging.

The role of insulin-like growth factor 2 receptor-mediated homeobox gene expression in human placental apoptosis, and its implications in idiopathic fetal growth restriction.

Fetal growth restriction (FGR) is caused by poor placental development and function early in gestation. It is well known that placentas from women with FGR exhibit reduced cell growth, elevated levels of apoptosis and perturbed expression of the growth factors, cytokines and the homeobox gene family of transcription factors. Previous studies have reported that insulin-like growth factor-2 (IGF2) interacts with its receptor-2 (IGF2R) to regulate villous trophoblast survival and apoptosis. In this study, we hypothesized that human placental IGF2R-mediated homeobox gene expression is altered in FGR and contributes to abnormal trophoblast function. This study was designed to determine the association between IGF2R, homeobox gene expression and cell survival in pregnancies affected by FGR. Third trimester placentas were collected from FGR-affected pregnancies (n = 29) and gestation matched with control pregnancies (n = 30). Functional analyses were then performed in vitro using term placental explants (n = 4) and BeWo trophoblast cells. mRNA expression was determined by real-time PCR, while protein expression was examined by immunoblotting and immunohistochemistry. siRNA transfection was used to silence IGF2R expression in placental explants and the BeWo cell-line. cDNA arrays were used to screen for downstream targets of IGF2R, specifically homeobox gene transcription factors and apoptosis-related genes. Functional effects of silencing IGF2R were then verified by ß-hCG ELISA, caspase activity assays and a real-time electrical cell-impedance assay for differentiation, apoptosis and cell growth potential, respectively. IGF2R expression was significantly decreased in placentas from pregnancies complicated by idiopathic FGR (P < 0.05 versus control). siRNA-mediated IGF2R knockdown in term placental explants and the trophoblast cell line BeWo resulted in altered expression of homeobox gene transcription factors, including increased expression of distal-less homeobox gene 5 (DLX5), and decreased expression of H2.0-Like Homeobox 1 (HLX) (P < 0.05 versus control). Knockdown of IGF2R transcription increased the expression and activity of caspase-6 and caspase-8 in placental explants, decreased BeWo proliferation and increased BeWo differentiation (all P < 0.05 compared to respective controls). This is the first study linking IGF2R placental expression with changes in the expression of homeobox genes that control cellular signalling pathways responsible for increased trophoblast cell apoptosis, which is a characteristic feature of FGR.

Iron Deposition Leads to Hyperphosphorylation of Tau and Disruption of Insulin Signaling.

Iron deposition in the brain is an early issue in Alzheimer's disease (AD). However, the pathogenesis of iron-induced pathological changes in AD remains elusive. Insulin resistance in brains is an essential feature of AD. Previous studies determined that insulin resistance is involved in the development of pathologies in AD. Tau pathology is one of most important hallmarks in AD and is associated with the impairment of cognition and clinical grades of the disease. In the present study, we observed that ferrous (Fe2+) chloride led to aberrant phosphorylation of tau, and decreased tyrosine phosphorylation levels of insulin receptor ß (IRß), insulin signal substrate 1 (IRS-1) and phosphoinositide 3-kinase p85α (PI3K p85α), in primary cultured neurons. In the in vivo studies using mice with supplemented dietary iron, learning and memory was impaired. As well, hyperphosphorylation of tau and disrupted insulin signaling in the brain was induced in iron-overloaded mice. Furthermore, in our in vitro work we identified the activation of insulin signaling following exogenous supplementation of insulin. This was further attenuated by iron-induced hyperphosphorylation of tau in primary neurons. Together, these data suggest that dysfunctional insulin signaling participates in iron-induced abnormal phosphorylation of tau in AD. Our study highlights the promising role of insulin signaling in pathological lesions induced by iron overloading.

Placenta Stem/Stromal Cell-Derived Extracellular Vesicles for Potential Use in Lung Repair.

Many acute and chronic lung injuries are incurable and rank as the fourth leading cause of death globally. While stem cell treatment for lung injuries is a promising approach, there is growing evidence that the therapeutic efficacy of stem cells originates from secreted extracellular vesicles (EVs). Consequently, EVs are emerging as next-generation therapeutics. While EVs are extensively researched for diagnostic applications, their therapeutic potential to promote tissue repair is not fully elucidated. By housing and delivering tissue-repairing cargo, EVs refine the cellular microenvironment, modulate inflammation, and ultimately repair injury. Here, the potential use of EVs derived from two placental mesenchymal stem/stromal cell (MSC) lines is presented; a chorionic MSC line (CMSC29) and a decidual MSC cell line (DMSC23) for applications in lung diseases. Functional analyses using in vitro models of injury demonstrate that these EVs have a role in ameliorating injuries caused to lung cells. It is also shown that EVs promote repair of lung epithelial cells. This study is fundamental to advancing the field of EVs and to unlock the full potential of EVs in regenerative medicine.

Isolation and Characterization of Extracellular Vesicles from Mesenchymal Stromal Cells.

Extracellular vesicles (EVs) have received immense attention in the past decade for their diverse use in diagnosis and therapeutics. Enhancing our understanding of EVs and increasing the reliability and reproducibility of EV research demands the use of standard isolation procedures and multiple characterization methods. Here we describe the most commonly used EV isolation method involving ultracentrifugation, and various characterization methods that include nanoparticle tracking analysis, atomic force microscopy and electron microscopy, which measure the size, concentration, and morphology of EVs.