Immunoregulatory Macrophages Modify Local Pulmonary Immunity and Ameliorate Hypoxic Pulmonary Hypertension.

BACKGROUND: Macrophages play a significant role in the onset and progression of vascular disease in pulmonary hypertension, and cell-based immunotherapies aimed at treating vascular remodeling are lacking. To evaluate the effect of pulmonary administration of macrophages modified to have an anti-inflammatory/proresolving phenotype in attenuating early pulmonary inflammation and progression of experimentally induced pulmonary hypertension. METHODS: Mouse bone marrow-derived macrophages were polarized in vitro to a regulatory (M2reg) phenotype. M2reg profile and anti-inflammatory capacity were assessed in vitro upon lipopolysaccharide/IFNγ (interferon-γ) restimulation, before their administration to 8- to 12-week-old mice. M2reg protective effect was evaluated at early (2-4 days) and late (4 weeks) time points during hypoxia (8.5% O2) exposure. Levels of inflammatory markers were quantified in alveolar macrophages and whole lung, while pulmonary hypertension development was ascertained by right ventricular systolic pressure (RVSP) and right ventricular hypertrophy measurements. Bronchoalveolar lavage from M2reg-transplanted hypoxic mice was collected and its inflammatory potential evaluated on naive bone marrow-derived macrophages. RESULTS: M2reg macrophages expressing Tgfß, Il10, and Cd206 demonstrated a stable anti-inflammatory phenotype in vitro, by downregulating the induction of proinflammatory cytokines and surface molecules (Cd86, Il6, and Tnfα) upon a subsequent proinflammatory stimulus. A single dose of M2reg attenuated hypoxic monocytic recruitment and perivascular inflammation. Early hypoxic lung and alveolar macrophage inflammation leading to pulmonary hypertension development was significantly reduced, and, importantly, M2reg attenuated right ventricular hypertrophy, right ventricular systolic pressure, and vascular remodeling at 4 weeks post-treatment. CONCLUSIONS: Adoptive transfer of M2reg halts the recruitment of monocytes and modifies the hypoxic lung microenvironment, potentially changing the immunoreactivity of recruited macrophages and restoring normal immune functionality of the lung. These findings provide new mechanistic insights into the diverse role of macrophage phenotype on lung vascular homeostasis that can be explored as novel therapeutic targets.

Pyroptosis is involved in maternal nicotine exposure-induced metabolic associated fatty liver disease progression in offspring mice.

We have investigated whether inflammasomes and pyroptosis are activated in maternal nicotine exposure (MNE) offspring mice and whether they are involved in MNE-promoted metabolic associated fatty liver disease (MAFLD) in adult offspring. We injected pregnant mice subcutaneously with saline vehicle or nicotine twice a day on gestational days 11-21. Offspring mice from both groups were fed with a normal diet (ND) or a high-fat diet (HFD) for 6 months at postnatal day 21 to develop the MAFLD model. Serum biochemical indices were analyzed, and liver histology was performed. The expression levels of inflammasome and pyroptosis proteins were detected by western blot. We found MNE significantly aggravated the injury of MAFLD in adult offspring mice. MNE activated inflammasomes and pyroptosis in both infant and adult offspring mice. HFD treatment activated inflammasomes but not pyroptosis at 3 months, while it showed no effect at 6 months. However, pyroptosis was more severe in MNE-HFD mice than in MNE-ND mice at 6 months. Taken together, our data suggest MNE promotes MAFLD progression in adult offspring mice. MNE also induces NLRP3 and NLRP6 inflammasome activation and pyroptosis in both infant and adult offspring mice, which may be involved in MNE-promoted progression of MAFLD.

Antenatal Mesenchymal Stromal Cell Extracellular Vesicle Therapy Prevents Preeclamptic Lung Injury in Mice.

In preeclamptic pregnancies, a variety of intrauterine alterations lead to abnormal placentation, release of inflammatory and/or antiangiogenic factors, and subsequent fetal growth restriction with significant potential to cause a primary insult to the developing fetal lung. Thus, modulation of the maternal intrauterine environment may be a key therapeutic avenue to prevent preeclampsia-associated developmental lung injury. A biologic therapy of interest is mesenchymal stromal cell-derived extracellular vesicles (MEx), which we have previously shown to ameliorate preeclamptic physiology through intrauterine immunomodulation. To evaluate the therapeutic potential of MEx to improve developmental lung injury in experimental preeclampsia, using the heme oxygenase-1-null mouse (Hmox1-/-) model, preeclamptic pregnant dams were administered intravenous antenatal MEx treatment during each week of pregnancy followed by analysis of fetal and postnatal lung tissues, amniotic fluid protein profiles, and lung explant and amniotic fluid cocultures in comparison with control and untreated preeclamptic pregnancies. We first identified that a preeclamptic intrauterine environment had a significant adverse impact on fetal lung development, including alterations in fetal lung developmental gene profiles in addition to postnatal alveolar and bronchial changes. Amniotic fluid proteomic analysis and fetal lung explant and amniotic fluid cocultures further demonstrated that maternally administered MEx altered the expression of multiple inflammatory mediators in the preeclamptic intrauterine compartment, resulting in the normalization of fetal lung branching morphogenesis and developmental gene expression. Our evaluation of fetal and postnatal parameters overall suggests that antenatal MEx treatment may provide a highly valuable preventative therapeutic modality for amelioration of lung development in preeclamptic disease.

Extracellular Vesicles Protect the Neonatal Lung from Hyperoxic Injury through the Epigenetic and Transcriptomic Reprogramming of Myeloid Cells.

Rationale: Mesenchymal stem/stromal cell (MSC)-small extracellular vesicle (MEx) treatment has shown promise in experimental models of neonatal lung injury. The molecular mechanisms by which MEx afford beneficial effects remain incompletely understood. Objectives: To investigate the therapeutic mechanism of action through assessment of MEx biodistribution and impact on immune cell phenotypic heterogeneity. Methods: MEx were isolated from the conditioned medium of human umbilical cord Wharton's jelly-derived MSCs. Newborn mice were exposed to hyperoxia (HYRX, 75% O2) from birth and returned to room air at Postnatal Day 14 (PN14). Mice received either a bolus intravenous MEx dose at PN4 or bone marrow-derived myeloid cells (BMDMy) pretreated with MEx. Animals were killed at PN4, PN7, PN14, or PN28 to characterize MEx biodistribution or for assessment of pulmonary parameters. The therapeutic role of MEx-educated BMDMy was determined in vitro and in vivo. Measurements and Main Results: MEx therapy ameliorated core histological features of HYRX-induced neonatal lung injury. Biodistribution and mass cytometry studies demonstrated that MEx localize in the lung and interact with myeloid cells. MEx restored the apportion of alveolar macrophages in the HYRX-injured lung and concomitantly suppressed inflammatory cytokine production. In vitro and ex vivo studies revealed that MEx promoted an immunosuppressive BMDMy phenotype. Functional assays demonstrated that the immunosuppressive actions of BMDMy are driven by phenotypically and epigenetically reprogrammed monocytes. Adoptive transfer of MEx-educated BMDMy, but not naive BMDMy, restored alveolar architecture, blunted fibrosis and pulmonary vascular remodeling, and improved exercise capacity. Conclusions: MEx ameliorate hyperoxia-induced neonatal lung injury though epigenetic and phenotypic reprogramming of myeloid cells.

Mesenchymal stromal cell-derived extracellular vesicle therapy prevents preeclamptic physiology through intrauterine immunomodulation†.

Human umbilical cord-derived mesenchymal stromal cells (MSCs) are a widely recognized treatment modality for a variety of preclinical disease models and have been transitioned to human clinical trials. We have previously shown in neonatal lung disease that the therapeutic capacity of MSCs is conferred by their secreted extracellular vesicles (MEx), which function primarily through immunomodulation. We hypothesize that MEx have significant therapeutic potential pertinent to immune-mediated gestational diseases. Of particular interest is early-onset preeclampsia, which can be caused by alterations of the maternal intrauterine immune environment. Using a heme-oxygenase-1 null mouse model of pregnancy loss with preeclampsia-like features, we examined the preventative effects of maternal MEx treatment early in pregnancy. Heme oxygenase-1 null females (Hmox1-/-) or wild-type control females were bred in homozygous matings followed by evaluation of maternal and fetal parameters. A single dose of MEx was administered intravenously on gestational day (GD)1 to Hmox1-/- females (Hmox1-/- MEx). Compared with untreated Hmox1-/- females, Hmox1-/- MEx-treated pregnancies showed significant improvement in fetal loss, intrauterine growth restriction, placental spiral artery modification, and maternal preeclamptic stigmata. Biodistribution studies demonstrated that MEx localize to a subset of cells in the preimplantation uterus. Further, mass cytometric (CyTOF) evaluation of utero-placental leukocytes in Hmox1-/- MEx versus untreated pregnancies showed alteration in the abundance, surface marker repertoire, and cytokine profiles of multiple immune populations. Our data demonstrate the therapeutic potential of MEx to optimize the intrauterine immune environment and prevent maternal and fetal sequelae of preeclamptic disease.

Maternal nicotine exposure aggravates metabolic associated fatty liver disease via PI3K/Akt signaling in adult offspring mice.

AIM: The aim of this study is to investigate the effect of maternal nicotine exposure (MNE) on the development of metabolic associated fatty liver disease (MAFLD) in adulthood offspring and the underlying mechanism. METHODS: Pregnant mice (n = 22) were subcutaneously injected with either saline vehicle (n = 11) or nicotine (n = 11) twice a day on gestational days 11-21. Offspring mice (n = 176) from both groups were weaned at postnatal day 21, and for 6 months after postnatal day 21, 96 mice were fed either a standard chow diet (n = 48) or a high-fat diet (n = 48). Serum lipid indicators, liver function indicators, insulin, and liver mitochondrial respiration were analyzed. The expression levels of fibrosis-related proteins, phosphorylated PI3K, phosphorylated Akt, sterol regulatory element-binding transcription factor 1 (SREBP1c), and peroxisome proliferator-activated receptor alpha (PPAR-α) were detected in the liver by immunohistochemistry and Western blotting. RESULTS: MNE significantly decreased the weight of both maternal and offspring mice (~30%) and inhibited organ growth in offspring mice (P < .05). MNE also significantly increased serum levels of total bile acid, triglycerides, total cholesterol, glucose, alanine aminotransferase, aspartate aminotransferase, low-density lipoprotein, and insulin while decreasing serum high-density lipoprotein levels and mitochondrial respiration activity in mice fed either the normal diet or high-fat diet (all P < .05). These effects of MNE on lipid metabolism and insulin resistance were mediated via PI3K and Akt phosphorylation and down-regulation of SREBP1c and PPAR-α. CONCLUSION: Our data indicate MNE induces lipid metabolism disorder and insulin resistance to promote MAFLD progression in adult offspring through activation of PI3K/Akt signaling and suppression of SREBP1c and PPARα protein expression.

Microcystic pattern and shadowing are independent predictors of ovarian borderline tumors and cystadenofibromas in ultrasound.

OBJECTIVES: To determine the sonographic characteristics of borderline tumors (BoTs) and cystadenofibromas (CAFs). METHODS: Preoperative sonograms from consecutive patients who had at least one primary epithelial tumor in the adnexa were retrospectively collected. All tumors were described using the International Ovarian Tumor Analysis terminology. Ultrasound variables were tested using multinomial logistic regression after univariate analysis. RESULTS: A total of 650 patients were included in this study. Of these, 110 had a CAF, 128 had a BoT, 249 had a cystadenoma (CAD), and 163 had a cystadenocarcinoma (CAC). Nearly half of CAFs and more than half of BoTs and CACs appeared to be unilocular and multilocular solid on the ultrasound images, while CADs were predominantly uni- or multilocular (p < 0.001). Overall, shadowing was identified in 82/650 cases. Sixty-five of 110 (59.1%) CAFs exhibited an acoustic shadow, compared with only 4/249 (1.6%) in CADs, 7/128 (5.5%) in BoTs, and 6/163 (3.7%) in CACs (p < 0.001). Furthermore, 112/650 cases demonstrated microcystic pattern (MCP). Sixty-eight of 128 (53.1%) BoTs exhibited MCP, compared with only 5/249 (2.0%) in CADs, 19/163 (11.7%) in CACs, and 20/110 (18.2%) in CAFs (p < 0.001). Logistic regression analysis revealed that shadowing is an independent predictor of CAFs, while MCP is an independent predictor of BoTs. CONCLUSIONS: Sonographic findings for CAFs and BoTs were complex and partly overlapped with those for CACs. However, proper recognition and utilization of shadowing or MCP may help to correctly discriminate CAFs and BoTs. KEY POINTS: • Sonographic findings for borderline tumors and cystadenofibromas are complex and mimic malignancy. • Microcystic pattern and shadowing are independent predictors of borderline tumors and cystadenofibromas respectively.

Mesenchymal Stromal Cell Exosomes Ameliorate Experimental Bronchopulmonary Dysplasia and Restore Lung Function through Macrophage Immunomodulation.

RATIONALE: Mesenchymal stem/stromal cell (MSC) therapies have shown promise in preclinical models of pathologies relevant to newborn medicine, such as bronchopulmonary dysplasia (BPD). We have reported that the therapeutic capacity of MSCs is comprised in their secretome, and demonstrated that the therapeutic vectors are exosomes produced by MSCs (MSC-exos). OBJECTIVES: To assess efficacy of MSC-exo treatment in a preclinical model of BPD and to investigate mechanisms underlying MSC-exo therapeutic action. METHODS: Exosomes were isolated from media conditioned by human MSC cultures. Newborn mice were exposed to hyperoxia (HYRX; 75% O2), treated with exosomes on Postnatal Day (PN) 4 and returned to room air on PN7. Treated animals and appropriate controls were harvested on PN7, -14, or -42 for assessment of pulmonary parameters. MEASUREMENTS AND MAIN RESULTS: HYRX-exposed mice presented with pronounced alveolar simplification, fibrosis, and pulmonary vascular remodeling, which was effectively ameliorated by MSC-exo treatment. Pulmonary function tests and assessment of pulmonary hypertension showed functional improvements after MSC-exo treatment. Lung mRNA sequencing demonstrated that MSC-exo treatment induced pleiotropic effects on gene expression associated with HYRX-induced inflammation and immune responses. MSC-exos modulate the macrophage phenotype fulcrum, suppressing the proinflammatory "M1" state and augmenting an antiinflammatory "M2-like" state, both in vitro and in vivo. CONCLUSIONS: MSC-exo treatment blunts HYRX-associated inflammation and alters the hyperoxic lung transcriptome. This results in alleviation of HYRX-induced BPD, improvement of lung function, decrease in fibrosis and pulmonary vascular remodeling, and amelioration of pulmonary hypertension. The MSC-exo mechanism of action is associated with modulation of lung macrophage phenotype.

Reference ranges of fetal spleen biometric parameters and volume assessed by three-dimensional ultrasound and their applicability in spleen malformations.

AIM: The aims of this article are to establish three-dimensional ultrasonographic nomograms of normal fetal spleen size and to evaluate the clinical application value. METHODS: An observational, cross-sectional study was performed on 455 women with a normal singleton pregnancy between 18 and 38 weeks' gestational age (GA). Fetal spleen volume was measured using three-dimensional ultrasound equipped with virtual organ computer-aided analysis, and biometric parameters were assessed in multiplanar mode to create reference ranges to GA. Thirty cases were randomly selected to conduct reliability analyses via intraobserver and interobserver ultrasonographic measurement. Moreover, 50 cases of suspected splenic malformations were evaluated by the newly established nomograms and followed up subsequently. RESULTS: Using regression formulas, we found that fetal spleen size increased with GA. We observed strong reliability in intraobserver and interobserver volume measurements with intraclass correlation coefficients of 0.994 and 0.962. Bland-Altman analyses showed narrow limits of agreement [intraobserver: (-3.2 to 3.5)%; interobserver: (-3.2 to 4.3)%]. Of the 50 cases with suspected splenic malformations, six cases of splenomegaly and one case of splenic cyst were diagnosed. CONCLUSION: Three-dimensional ultrasound nomograms of normal fetal spleen size across a range of GA have a strong diagnostic value. Volume measurements with good reliability were optimal in clinical practice.

The Gene Expression Profiles Associated with Maternal Nicotine Exposure in the Liver of Offspring Mice.

This study aims to investigate the effect of maternal nicotine exposure on the gene expression profiles in the liver of offspring mice. Pregnant mice were subcutaneously injected with either saline vehicle or nicotine twice a day on gestational days 11-21. Total RNA from the liver samples which collected from the offspring mice of postnatal day 7 and 21 was subjected to RNA sequencing. Gene Ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway enrichment analysis were conducted to identify the functions of differentially expressed genes (DEGs). Four genes were selected for further validation by quantitative reverse transcription polymerase chain reaction (qRT-PCR). A total of 448 DEGs and 186 DEGs were identified on postnatal day 7 and 21, respectively. GO analysis revealed that the DEGs on postnatal day 7 mainly participated in the biological functions of cell growth and proliferation, and the DEGs on postnatal day 21 mainly participated in ion transport/activity. KEGG enrichment analysis showed that the DEGs on postnatal day 7 were mainly enriched in the cell cycle, cytokine-cytokine receptor interactions, hypertrophic cardiomyopathy, and the p53 signaling pathway, while the DEGs on postnatal day 21 were mainly enriched in neuroactive ligand-receptor interactions, the calcium signaling pathway, retinol metabolism, and axon guidance. The qRT-PCR results were consistent with the RNA sequencing data. The DEGs may affect the growth of liver in early postnatal period while may affect ion transport/activity in late postnatal period.

The Ratio of Clavicle Length to Head Circumference: A Novel Date-Independent Clavicle Index.

ABSTRACT: We aimed to plot the growth curve of the fetal clavicle, identify gestational date-independent parameters. Using 2-dimensional ultrasonography, we obtained the clavicle lengths (CLs) from 601 normal fetuses between 12 and 40 gestational age (GA). The CL/fetal growth parameters ratio was calculated. Moreover, 27 cases of fetal growth restriction (FGR) and 9 cases of small for GA (SGA) were detected. In normal fetuses, the mean CL (mm) = -68.2 + 29.80 × ln(GA) ± Z × (1.07 + 0.02 × GA). A linear relationship was detected between CL and head circumference (HC), biparietal diameter, abdominal circumference and femoral length with R2 values of 0.973, 0.970, 0.962, and 0.972, respectively. The CL/HC ratio (mean value 0.130) showed no significant correlation with GA. Clavicle lengths in the FGR group significantly decreased compared with the SGA group ( P < 0.01). This study determined a reference range of fetal CL in a Chinese population. Furthermore, the CL/HC ratio, which is independent of GA, is a novel parameter for the evaluation of the fetal clavicle.

Immunoregulatory macrophages modify local pulmonary immunity and ameliorate hypoxic-pulmonary hypertension.

Rationale: Macrophages play a central role in the onset and progression of vascular disease in pulmonary hypertension (PH) and cell-based immunotherapies aimed at treating vascular remodeling are lacking. Objective: To evaluate the effect of pulmonary administration of macrophages modified to have an anti-inflammatory/pro-resolving phenotype in attenuating early pulmonary inflammation and progression of experimentally induced PH. Methods: Mouse bone marrow derived macrophages (BMDMs) were polarized in vitro to a regulatory (M2 reg ) phenotype. M2 reg profile and anti-inflammatory capacity were assessed in vitro upon lipopolysaccharide (LPS)/interferon-γ (IFNγ) restimulation, before their administration to 8- to 12-week-old mice. M2 reg protective effect was tested at early (2 to 4 days) and late (4 weeks) time points during hypoxia (8.5% O 2 ) exposure. Levels of inflammatory markers were quantified in alveolar macrophages and whole lung, while PH development was ascertained by right ventricular systolic pressure (RSVP) and right ventricular hypertrophy (RVH) measurements. Bronchoalveolar lavage (BAL) from M2 reg -transplanted hypoxic mice was collected, and its inflammatory potential tested on naïve BMDMs. Results: M2 reg macrophages demonstrated a stable anti-inflammatory phenotype upon a subsequent pro-inflammatory stimulus by maintaining the expression of specific anti-inflammatory markers (Tgfß, Il10 and Cd206) and downregulating the induction of proinflammatory cytokines and surface molecules (Cd86, Il6 and Tnfα). A single dose of M2 regs attenuated the hypoxic monocytic recruitment and perivascular inflammation. Early hypoxic lung and alveolar macrophage inflammation leading to PH development was significantly reduced and, importantly, M2 regs attenuated RVH, RVSP and vascular remodeling at 4 weeks post treatment. Conclusions: Adoptive transfer of M2 regs halts the recruitment of monocytes and modifies the hypoxic lung microenvironment, potentially changing the immunoreactivity of recruited macrophages and restoring normal immune functionality of the lung. These findings provide new mechanistic insights on the diverse role of macrophage phenotype on lung vascular homeostasis that can be explored as novel therapeutic targets.

Early macrophage recruitment and alternative activation are critical for the later development of hypoxia-induced pulmonary hypertension.

BACKGROUND: Lung inflammation precedes the development of hypoxia-induced pulmonary hypertension (HPH); however, its role in the pathogenesis of HPH is poorly understood. We sought to characterize the hypoxic inflammatory response and to elucidate its role in the development of HPH. We also aimed to investigate the mechanisms by which heme oxygenase-1, an anti-inflammatory enzyme, is protective in HPH. METHODS AND RESULTS: We generated bitransgenic mice that overexpress human heme oxygenase-1 under doxycycline control in an inducible, lung-specific manner. Hypoxic exposure of mice in the absence of doxycycline resulted in early transient accumulation of monocytes/macrophages in the bronchoalveolar lavage. Alveolar macrophages acquired an alternatively activated phenotype (M2) in response to hypoxia, characterized by the expression of found in inflammatory zone-1, arginase-1, and chitinase-3-like-3. A brief 2-day pulse of doxycycline delayed, but did not prevent, the peak of hypoxic inflammation, and could not protect against HPH. In contrast, a 7-day doxycycline treatment sustained high heme oxygenase-1 levels during the entire period of hypoxic inflammation, inhibited macrophage accumulation and activation, induced macrophage interleukin-10 expression, and prevented the development of HPH. Supernatants from hypoxic M2 macrophages promoted the proliferation of pulmonary artery smooth muscle cells, whereas treatment with carbon monoxide, a heme oxygenase-1 enzymatic product, abrogated this effect. CONCLUSIONS: Early recruitment and alternative activation of macrophages in hypoxic lungs are critical for the later development of HPH. Heme oxygenase-1 may confer protection from HPH by effectively modifying the macrophage activation state in hypoxia.

Vasculoprotective effects of heme oxygenase-1 in a murine model of hyperoxia-induced bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) is characterized by simplified alveolarization and arrested vascular development of the lung with associated evidence of endothelial dysfunction, inflammation, increased oxidative damage, and iron deposition. Heme oxygenase-1 (HO-1) has been reported to be protective in the pathogenesis of diseases of inflammatory and oxidative etiology. Because HO-1 is involved in the response to oxidative stress produced by hyperoxia and is critical for cellular heme and iron homeostasis, it could play a protective role in BPD. Therefore, we investigated the effect of HO-1 in hyperoxia-induced lung injury using a neonatal transgenic mouse model with constitutive lung-specific HO-1 overexpression. Hyperoxia triggered an increase in pulmonary inflammation, arterial remodeling, and right ventricular hypertrophy that was attenuated by HO-1 overexpression. In addition, hyperoxia led to pulmonary edema, hemosiderosis, and a decrease in blood vessel number, all of which were markedly improved in HO-1 overexpressing mice. The protective vascular response may be mediated at least in part by carbon monoxide, due to its anti-inflammatory, antiproliferative, and antiapoptotic properties. HO-1 overexpression, however, did not prevent alveolar simplification nor altered the levels of ferritin and lactoferrin, proteins involved in iron binding and transport. Thus the protective mechanisms elicited by HO-1 overexpression primarily preserve vascular growth and barrier function through iron-independent, antioxidant, and anti-inflammatory pathways.

Mesenchymal stromal cells expressing heme oxygenase-1 reverse pulmonary hypertension.

Pulmonary arterial hypertension (PAH) remains a serious disease, and although current treatments may prolong and improve quality of life, search for novel and effective therapies is warranted. Using genetically modified mouse lines, we tested the ability of bone marrow-derived stromal cells (mesenchymal stem cells [MSCs]) to treat chronic hypoxia-induced PAH. Recipient mice were exposed for 5 weeks to normobaric hypoxia (8%-10% O(2)), MSC preparations were delivered through jugular vein injection and their effect on PAH was assessed after two additional weeks in hypoxia. Donor MSCs derived from wild-type (WT) mice or heme oxygenase-1 (HO-1) null mice (Hmox1(KO)) conferred partial protection from PAH when transplanted into WT or Hmox1(KO) recipients, whereas treatment with MSCs isolated from transgenic mice harboring a human HO-1 transgene under the control of surfactant protein C promoter (SH01 line) reversed established disease in WT recipients. SH01-MSC treatment of Hmox1(KO) animals, which develop right ventricular (RV) infarction under prolonged hypoxia, resulted in normal RV systolic pressure, significant reduction of RV hypertrophy and prevention of RV infarction. Donor MSCs isolated from a bitransgenic mouse line with doxycycline-inducible, lung-specific expression of HO-1 exhibited similar therapeutic efficacy only on doxycycline treatment of the recipients. In vitro experiments indicate that potential mechanisms of MSC action include modulation of hypoxia-induced lung inflammation and inhibition of smooth muscle cell proliferation. Cumulatively, our results demonstrate that MSCs ameliorate chronic hypoxia-induced PAH and their efficacy is highly augmented by lung-specific HO-1 expression in the transplanted cells, suggesting an interplay between HO-1-dependent and HO-1-independent protective pathways.

Case report and literature review: antenatal diagnosis of a fetal anaplastic astrocytoma.

OBJECTIVES: To describe the ultrasonographic appearance of congenital anaplastic astrocytoma, so as to provide diagnostic clues for it. An updated review of the literature was also carried out. RESULTS: There was a case of fetal anaplastic astrocytoma detected by ultrasound at 37 + 1 weeks of gestation. It showed that a hypoechoic mass was located in the left hemisphere with a relatively clear margin and subtle color flows. Prenatal magnetic resonance imaging (MRI) which was taken subsequently confirmed the result of ultrasound. Intratumoral hemorrhage was observed in later follow-up and further confirmed by histological examination. The fetus was delivered vaginally at 39 + 6 weeks. The infant died 2 h after delivery due to respiration failure. The histological examination confirmed an anaplastic astrocytoma. CONCLUSIONS: Congenital anaplastic astrocytoma commonly detected by ultrasound has a relatively better perinatal prognosis, especially compared with glioblastoma. Prenatal ultrasonography diagnosis accurately is of critical importance. The anaplastic astrocytoma should be considered in cases in which fetal images reveal a heterogeneous echogenic mass in the brain, especially in the presence of intratumoral hemorrhage, subtle color flow, and relatively clear margin.

Therapeutic Effects of Mesenchymal Stromal Cell-Derived Small Extracellular Vesicles in Oxygen-Induced Multi-Organ Disease: A Developmental Perspective.

Despite major advances in neonatal intensive care, infants born at extremely low birth weight still face an increased risk for chronic illness that may persist into adulthood. Pulmonary, retinal, and neurocognitive morbidities associated with preterm birth remain widespread despite interventions designed to minimize organ dysfunction. The design of therapeutic applications for preterm pathologies sharing common underlying triggers, such as fluctuations in oxygen supply or in the inflammatory state, requires alternative strategies that promote anti-inflammatory, pro-angiogenic, and trophic activities-ideally as a unitary treatment. Mesenchymal stem/stromal cell-derived extracellular vesicles (MEx) possess such inherent advantages, and they represent a most promising treatment candidate, as they have been shown to contribute to immunomodulation, homeostasis, and tissue regeneration. Current pre-clinical studies into the MEx mechanism of action are focusing on their restorative capability in the context of preterm birth-related pathologies, albeit not always with a multisystemic focus. This perspective will discuss the pathogenic mechanisms underlying the multisystemic lesions resulting from early-life disruption of normal physiology triggered by high oxygen exposures and pro-inflammatory conditions and introduce the application of MEx as immunomodulators and growth-promoting mediators for multisystem therapy.

Mesenchymal Stromal Cell-Derived Extracellular Vesicles Restore Thymic Architecture and T Cell Function Disrupted by Neonatal Hyperoxia.

Treating premature infants with high oxygen is a routine intervention in the context of neonatal intensive care. Unfortunately, the increase in survival rates is associated with various detrimental sequalae of hyperoxia exposure, most notably bronchopulmonary dysplasia (BPD), a disease of disrupted lung development. The effects of high oxygen exposure on other developing organs of the infant, as well as the possible impact such disrupted development may have on later life remain poorly understood. Using a neonatal mouse model to investigate the effects of hyperoxia on the immature immune system we observed a dramatic involution of the thymic medulla, and this lesion was associated with disrupted FoxP3+ regulatory T cell generation and T cell autoreactivity. Significantly, administration of mesenchymal stromal cell-derived extracellular vesicles (MEx) restored thymic medullary architecture and physiological thymocyte profiles. Using single cell transcriptomics, we further demonstrated preferential impact of MEx treatment on the thymic medullary antigen presentation axis, as evidenced by enrichment of antigen presentation and antioxidative-stress related genes in dendritic cells (DCs) and medullary epithelial cells (mTECs). Our study demonstrates that MEx treatment represents a promising restorative therapeutic approach for oxygen-induced thymic injury, thus promoting normal development of both central tolerance and adaptive immunity.

Mesenchymal stromal cell-derived small extracellular vesicles restore lung architecture and improve exercise capacity in a model of neonatal hyperoxia-induced lung injury.

Early administration of mesenchymal stromal cell (MSC)-derived small extracellular vesicles (MEx) has shown considerable promise in experimental models of bronchopulmonary dysplasia (BPD). However, the ability of MEx to reverse the long-term pulmonary complications associated with established BPD remains unknown. In this study, MEx were isolated from media conditioned by human Wharton's Jelly-derived MSC cultures. Newborn mice (FVB strain) were exposed to hyperoxia (HYRX (75% O2)) before returning to room air at postnatal day 14 (PN14). Following prolonged HYRX-exposure, animals received a single MEx dose at PN18 or serial MEx treatments at PN18-39 ("late" intervention). This group was compared to animals that received an early single MEx dose at PN4 ("early" intervention). Animals were harvested at PN28 or 60 for assessment of pulmonary parameters. We found that early and late MEx interventions effectively ameliorated core features of HYRX-induced neonatal lung injury, improving alveolar simplification, pulmonary fibrosis, vascular remodelling and blood vessel loss. Exercise capacity testing and assessment of pulmonary hypertension (PH) showed functional improvements following both early and late MEx interventions. In conclusion, delivery of MEx following prolonged HYRX-exposure improves core features of experimental BPD, restoring lung architecture, decreasing pulmonary fibrosis and vascular muscularization, ameliorating PH and improving exercise capacity. Taken together, delivery of MEx may not only be effective in the immediate neonatal period to prevent the development of BPD but may provide beneficial effects for the management and potentially the reversal of cardiorespiratory complications in infants and children with established BPD.

The potential long-term neurological improvement of early hyperbaric oxygen therapy on hemorrhagic stroke in the diabetics.

AIMS: Although Hyperbaric oxygen therapy (HyperBOT) attract our attention successfully these days, it is still full of controversy on the treatment of acute stroke. The aim of this study is to assess the potential long-term neurological consequences and safety of using HyperBOT on intracerebral hemorrhage (ICH) in the diabetics. METHODS: In this prospective, randomized controlled trial, 79 diabetes patients suffering from acute ICH were randomized to treat for 60 min in a monoplace hyperbaric chamber pressurized with pure oxygen to 2.5-atm absolute (ATA) in the HyperBOT group or 1.5 ATA in the normobaric oxygen therapy (NormBOT) group, which was performed as control. Both short-term and long-term neurological consequences were studied and compared in each group on National Institutes of Health Stroke Scale [NIHSS], Barthel Index, modified Rankin Scale [mRS] and Glasgow Outcome Scale [GOS]. The related complications or side-events of all patients were recorded as well at the final follow-up of six months after onset. RESULTS: No distinct difference was observed between each group at one month follow-up. However, in the long-term follow-up of six months, a higher frequency of patients in the HyperBOT group resulted into good outcome with a relative high neurological consequence compared with the NormBOT group (Barthel Index: 85.1% versus 65.6%, P = 0.080; mRS: 89.4% versus 68.8%, P = 0.045; GOS: 83.0% versus 62.5%, P = 0.073; NIHSS: 80.9% versus 56.2%, P = 0.035). CONCLUSIONS: Early HyperBOT was found to be safe and effective with regards to the long-term neurological outcome of diabetic patients suffering from ICH.