An automated ICU agitation monitoring system for video streaming using deep learning classification.

OBJECTIVE: To address the challenge of assessing sedation status in critically ill patients in the intensive care unit (ICU), we aimed to develop a non-contact automatic classifier of agitation using artificial intelligence and deep learning. METHODS: We collected the video recordings of ICU patients and cut them into 30-second (30-s) and 2-second (2-s) segments. All of the segments were annotated with the status of agitation as "Attention" and "Non-attention". After transforming the video segments into movement quantification, we constructed the models of agitation classifiers with Threshold, Random Forest, and LSTM and evaluated their performances. RESULTS: The video recording segmentation yielded 427 30-s and 6405 2-s segments from 61 patients for model construction. The LSTM model achieved remarkable accuracy (ACC 0.92, AUC 0.91), outperforming other methods. CONCLUSION: Our study proposes an advanced monitoring system combining LSTM and image processing to ensure mild patient sedation in ICU care. LSTM proves to be the optimal choice for accurate monitoring. Future efforts should prioritize expanding data collection and enhancing system integration for practical application.

Deep Learning-Based Pain Classifier Based on the Facial Expression in Critically Ill Patients.

Objective: Pain assessment based on facial expressions is an essential issue in critically ill patients, but an automated assessment tool is still lacking. We conducted this prospective study to establish the deep learning-based pain classifier based on facial expressions. Methods: We enrolled critically ill patients during 2020-2021 at a tertiary hospital in central Taiwan and recorded video clips with labeled pain scores based on facial expressions, such as relaxed (0), tense (1), and grimacing (2). We established both image- and video-based pain classifiers through using convolutional neural network (CNN) models, such as Resnet34, VGG16, and InceptionV1 and bidirectional long short-term memory networks (BiLSTM). The performance of classifiers in the test dataset was determined by accuracy, sensitivity, and F1-score. Results: A total of 63 participants with 746 video clips were eligible for analysis. The accuracy of using Resnet34 in the polychromous image-based classifier for pain scores 0, 1, 2 was merely 0.5589, and the accuracy of dichotomous pain classifiers between 0 vs. 1/2 and 0 vs. 2 were 0.7668 and 0.8593, respectively. Similar accuracy of image-based pain classifier was found using VGG16 and InceptionV1. The accuracy of the video-based pain classifier to classify 0 vs. 1/2 and 0 vs. 2 was approximately 0.81 and 0.88, respectively. We further tested the performance of established classifiers without reference, mimicking clinical scenarios with a new patient, and found the performance remained high. Conclusions: The present study demonstrates the practical application of deep learning-based automated pain assessment in critically ill patients, and more studies are warranted to validate our findings.

YAP activity protects against endotoxemic acute lung injury by activating multiple mechanisms.

The roles of the Hippo­Yes­associated protein (YAP) pathway in lung injury and repair remain elusive. The present study examined the effects of systemic inhibition or stimulation of YAP activity on lung injury, repair and inflammation in a mouse model of lipopolysaccharide (LPS)­induced lung injury. Mice were treated with or without YAP inhibitor, verteporfin, or with or without YAP stimulator, XMU­MP­1, and intraperitoneally injected with LPS (7.5 mg/kg). Lung injury and repair were evaluated by histological analysis and by testing for markers of lung injury. Lung inflammation was assessed by measuring tissue levels of inflammatory mediators. Lung injury was associated with a decreased, whereas lung repair was associated with an increased YAP activity evidenced by nuclear translocation. Lung injury was associated with a high level of lung inflammation and epithelial adherens junction disassembly, but not with cell proliferation or epithelial cell regeneration. The injury phase was defined as 0­48 h post­LPS injection, and the 48­168 h time period was considered the repair phase. Inhibition of YAP activity at the injury phase, using verteporfin, exacerbated, whereas its stimulation, using XMU­MP­1, alleviated lung injury, lung inflammation and epithelial adherens junction disassembly. Inhibition or stimulation of YAP activity at the injury phase had no effects on cell proliferation or epithelial regeneration. By contrast, lung repair was associated with inflammation resolution, increased cell proliferation, epithelial regeneration and reassembly of epithelial adherens junctions. Inhibition of YAP activity at the repair phase delayed inflammation resolution, impeded lung recovery, inhibited cell proliferation and epithelial regeneration, and inhibited epithelial adherens junction reassembly. Stimulation of YAP activity at the repair phase reversed all these processes. The results of the current study demonstrated that the Hippo­YAP activity serves a protective role against endotoxemic lung injury. The Hippo­YAP activity alleviated lung inflammation and injury at the injury phase and promoted inflammation resolution and lung repair at the repair phase.

Hydrogen Attenuates Allergic Inflammation by Reversing Energy Metabolic Pathway Switch.

Mechanisms mediating the protective effects of molecular hydrogen (H2) are not well understood. This study explored the possibility that H2 exerts its anti-inflammatory effect by modulating energy metabolic pathway switch. Activities of glycolytic and mitochondrial oxidative phosphorylation systems were assessed in asthmatic patients and in mouse model of allergic airway inflammation. The effects of hydrogen treatment on airway inflammation and on changes in activities of these two pathways were evaluated. Monocytes from asthmatic patients and lungs from ovalbumin-sensitized and challenged mice had increased lactate production and glycolytic enzyme activities (enhanced glycolysis), accompanied by decreased ATP production and mitochondrial respiratory chain complex I and III activities (suppressed mitochondrial oxidative phosphorylation), indicating an energy metabolic pathway switch. Treatment of ovalbumin-sensitized and challenged mice with hydrogen reversed the energy metabolic pathway switch, and mitigated airway inflammation. Hydrogen abrogated ovalbumin sensitization and challenge-induced upregulation of glycolytic enzymes and hypoxia-inducible factor-1α, and downregulation of mitochondrial respiratory chain complexes and peroxisome proliferator activated receptor-γ coactivator-1α. Hydrogen abrogated ovalbumin sensitization and challenge-induced sirtuins 1, 3, 5 and 6 downregulation. Our data demonstrates that allergic airway inflammation is associated with an energy metabolic pathway switch from oxidative phosphorylation to aerobic glycolysis. Hydrogen inhibits airway inflammation by reversing this switch. Hydrogen regulates energy metabolic reprogramming by acting at multiple levels in the energy metabolism regulation pathways.

[Project to Increase the Percentage of Nursing Staffs Passing Clinical Ladder-3 Certification in the Intensive Care Unit].

BACKGROUND & PROBLEMS: Clinical ladder (CL)-3 nurses should have both an ability to integrate the clinical information of critically ill patients and to carry out the administrative work of the intensive care unit. However, in our unit, only 15.3% of nurses hold CL-3 certification, which is much lower than the hospital average of 23.1%. Thus, we initiated a project to raise this percentage in our unit. An analysis in January 2016 showed that the main obstacles to obtaining CL-3 certification in our unit were inability to write case reports, inadequate in-service education, and a lack of certified educators. PURPOSE: The purpose of this project was to increase the number of CL-3-certified nurses in our intensive care unit. RESOLUTION: The resolution included holding courses on case report writing, briefings, and oral presentation techniques; assigning a preceptor to make nursing staff assignments; encouraging nurses to participate in the clinical nursing preceptor education training camp; and conducting practice tests using a multiple assessment tool. RESULTS: After implementation of this project, the percentage of unit nurses who had passed CL-3 increased to 39.0%. CONCLUSIONS: This project not only allowed our fellow nurses to share in the joy of clinical ladder advancement but also improved the atmosphere in the unit by encouraging self-development. This project helped stimulate professional growth among our staff and improved the quality of clinical care.

The number and function of T regulatory cells in obese atopic female asthmatics.

BACKGROUND: Mechanisms underlying the association between asthma and obesity remain poorly understood. Obesity appears to be a risk factor for asthma, and obese asthmatics fare poorly compared to lean asthmatics. OBJECTIVES: To explore the possibility that reduced regulatory T cell (Treg) number and function contribute to the obesity-asthma association. We concentrated on obese females with childhood-onset asthma, since Treg may be involved in this phenotype. METHODS: We recruited 64 women (ages 18-50) into four groups: lean (BMI 18-25 kg/m2) controls (n = 17) and asthmatics (n = 13), and obese (BMI ≥ 35 kg/m2) controls (n = 17) and asthmatics (n = 17). Asthmatics had atopy and childhood-diagnosed asthma. We assessed lung function, asthma control and quality of life. Peripheral blood CD4+/CD25+/FoxP3+ Treg cells were identified and counted by flow cytometry and expressed as % total CD4+ T cells. We assessed Treg cell function by the ability of CD4+/CD25+ Treg cells to suppress autologous CD4+/CD25- responder T cell (Tresp) proliferation and measured as % suppression of Tresp cell proliferation. RESULTS: Obese asthmatics had worse lung function, asthma control, and quality of life compared to lean asthmatics. Compared to lean or obese control groups, the number of Treg cells in the obese asthmatics was approximately 1.58- or 1.73-fold higher. The ability of Treg cells from obese-asthmatics to suppress Tresp cell proliferation was reduced. CONCLUSIONS: Obese, atopic women with childhood diagnosed asthma demonstrate increased Treg cell number and mildly decreased Treg cell function. Our data do not support the view that reduced Treg cell number contributes to this obese-asthma phenotype.

MiR-324-5p reduces viability and induces apoptosis in gastric cancer cells through modulating TSPAN8.

OBJECTIVES: The purpose of this study was to further clarify the role and underlying mechanism of miR-324-5p in gastric cancer. METHODS: The expressions of miR-324-5p and TSPAN8 as determined by qRT-PCR or Western blot were compared between the gastric cancer tissues and normal tissues. Human gastric cancer cell line SGC-7901 was cultured and transfected with miR-324-5p mimic/inhibitor or pcDNA-TSPAN8. The cell survival was assessed by the cell viability and apoptosis. Luciferase reporter gene assays were performed to explore the interaction between miR-324-5p and TSPAN8 in SGC-7901 cells. KEY FINDINGS: MiR-324-5p was decreased in human gastric carcinoma tissues (n = 33), but TSPAN8 protein expression was increased in the gastric carcinoma tissues (n = 33). Moreover, miR-324-5p inhibited the viability and induced the apoptosis of gastric cancer cells in vitro. TSPAN8 is a functional target of miR-324-5p in gastric cancer. MiR-324-5p was further confirmed to reduce gastric cancer cell viability and induce apoptosis via downregulating TSPAN8 in SGC-7901 cells in vitro. Additionally, miR-324-5p overexpression markedly inhibited the tumorigenesis of gastric cancer cells in vivo, as shown by the smaller tumour volume compared with the control. CONCLUSIONS: This study suggested a novel, probable mechanism of miR-324-5p in gastric cancer context and revealed that miR-324-5p inhibited gastric cancer cell survival by targeting TSPAN8.

Selective inhibition of endothelial NF-κB signaling attenuates chronic intermittent hypoxia-induced atherosclerosis in mice.

BACKGROUND AND AIMS: Chronic intermittent hypoxia (CIH) exposure causes atherosclerosis, although the underlying mechanisms are poorly understood. This study defines the role of endothelial intrinsic NF-κB signaling in the atherogenic response to CIH. METHODS: We created ApoE-ECI-κBmt mice that are deficient in the apolipoprotein E gene (ApoE-/-) and overexpress an I-κBα mutant (I-κBmt) selectively in endothelial cells. ApoE-/- and ApoE-ECI-κBmt mice were fed a normal chow diet (NCD) or high cholesterol diet (HCD) and exposed to sham or CIH, and atherosclerotic lesions were quantified. RESULTS: CIH exposure activated NF-κB in aortas, and induced the expression of endothelial-specific and NF-κB-dependent genes, E-selectin and vascular cell adhesion molecule (VCAM)-1, in the aortas and hearts. Endothelial I-κBmt overexpression in ApoE-ECI-κBmt mice significantly inhibited CIH-induced NF-κB activity, and suppressed E-selectin and VCAM-1 expressions, confirming endothelial NF-κB inhibition in ApoE-ECI-κBmt mice. ApoE-/- mice, on NCD, developed mild atherosclerotic lesions spontaneously, and developed advanced and larger areas of atherosclerotic plaques when exposed to CIH. ApoE-/- mice also developed advanced atherosclerotic lesions when fed an HCD alone. The HCD-induced atherosclerotic plaques became more advanced, and plaque area was doubled in mice exposed to HCD + CIH. Endothelial I-κBmt overexpression in ApoE-ECI-κBmt mice attenuated spontaneously developed atherosclerotic lesions, abrogated CIH-induced atherosclerosis and mitigated CIH-mediated facilitation of HCD-induced atherosclerosis. CONCLUSIONS: These results suggest that endothelial intrinsic NF-kB signaling may play a pivotal role in CIH-induced atherosclerosis.

Hypoxia-induced activation of specific members of the NF-kB family and its relevance to pulmonary vascular remodeling.

BACKGROUND AND OBJECTIVE: Pulmonary Hypertension (pH) is a chronic progressive disease. Endothelial cells (EC) play a central and critical role in the initiation and progression of pH. The NF-κB family (NF-κB1 (p50/p105), NF-κB2 (p52/p100), RelA (p65), RelB, and C-Rel) regulates a wide array of genes involved in inflammatory responses, cell proliferation, and survival. The involvement of specific NF-κB family members in the pathogenesis of hypoxia-induced pH remains to be determined. The objective of this study was to assess the specific role of individual NF-κB family members in mediating endothelial cell responses to hypoxia and its downstream effect on smooth muscle cell proliferation. METHODS AND RESULTS: NF-κB family members' expression were selectively reduced by siRNA in human pulmonary microvascular endothelial cells. Cells were then exposed to hypoxia (1%) for 24h. Endothelin1, ICAM1 gene expression and Stat1 and Stat3 phosphorylation were assessed. Smooth muscle cells (SMC) proliferation was assessed by culturing them with EC conditioned media. Reduction of either NF-κB2 or RelA in EC, led to a significant decrease in Endothelin1 and ICAM1 gene expression. C-Rel knockdown resulted in a significant increase in phosphorylated STAT1; both C-Rel and RelA knockdown significantly decreased phosphorylated STAT3 in EC. There was a significant reduction in SMC proliferation, and AKT/ERK phosphorylation in SMC, when cultured in RelA knockdown, EC conditioned media. CONCLUSION: RelA in EC plays crucial role in hypoxia induced vascular remodeling and development of pH. Targeting RelA in EC alleviates SMC proliferation as well as inflammation related processes.

Blood pressure regulation by CD4+ lymphocytes expressing choline acetyltransferase.

Blood pressure regulation is known to be maintained by a neuro-endocrine circuit, but whether immune cells contribute to blood pressure homeostasis has not been determined. We previously showed that CD4+ T lymphocytes that express choline acetyltransferase (ChAT), which catalyzes the synthesis of the vasorelaxant acetylcholine, relay neural signals. Here we show that these CD4+CD44hiCD62Llo T helper cells by gene expression are a distinct T-cell population defined by ChAT (CD4 TChAT). Mice lacking ChAT expression in CD4+ cells have elevated arterial blood pressure, compared to littermate controls. Jurkat T cells overexpressing ChAT (JTChAT) decreased blood pressure when infused into mice. Co-incubation of JTChAT and endothelial cells increased endothelial cell levels of phosphorylated endothelial nitric oxide synthase, and of nitrates and nitrites in conditioned media, indicating increased release of the potent vasorelaxant nitric oxide. The isolation and characterization of CD4 TChAT cells will enable analysis of the role of these cells in hypotension and hypertension, and may suggest novel therapeutic strategies by targeting cell-mediated vasorelaxation.

[Spectroscopic Studies on the Interaction of Human Serum Albumin and Water-Soluble Carboxyl Carbon Nanotubes].

The interaction between nanomaterials and biological macromolecules (including protein) is the important basis of biological safety assessments of nanomaterials. In this paper, the fluorescence spectroscopy, synchronous fluorescence spectroscopy and circular dichroism spectroscopy) were used to analyze the interaction between four water-soluble carboxyl carbon nanotubes (long-SWCNTs-COOH, short-SWCNTs-COOH, DWCNTs-COOH and MWCNTs-COOH) and human serum albumin. Results showed that the four water-soluble carboxylated carbon nanotubes could quench the intrinsic fluorescence of human serum albumin at different extents. Under the same concentration, the quenching ability of four carboxylated carbon nanotubes were in the order of DWCNTs-COOH

Chronic intermittent hypoxia exposure-induced atherosclerosis: a brief review.

Obstructive sleep apnea (OSA) is highly prevalent in the USA and is recognized as an independent risk factor for atherosclerotic cardiovascular disease. Identification of atherosclerosis risk factor attributable to OSA may provide opportunity to develop preventive measures for cardiovascular risk reduction. Chronic intermittent hypoxia (CIH) is a prominent feature of OSA pathophysiology and may be a major mechanism linking OSA to arteriosclerosis. Animal studies demonstrated that CIH exposure facilitated high-cholesterol diet (HCD)-induced atherosclerosis, accelerated the progression of existing atherosclerosis, and induced atherosclerotic lesions in the absence of other atherosclerosis risk factors, demonstrating that CIH is an independent causal factor of atherosclerosis. Comparative studies revealed major differences between CIH-induced and the classic HCD-induced atherosclerosis. Systemically, CIH was a much weaker inducer of atherosclerosis. CIH and HCD differentially activated inflammatory pathways. Histologically, CIH-induced atherosclerotic plaques had no clear necrotic core, contained a large number of CD31+ endothelial cells, and had mainly elastin deposition, whereas HCD-induced plaques had typical necrotic cores and fibrous caps, contained few endothelial cells, and had mainly collagen deposition. Metabolically, CIH caused mild, but HCD caused more severe dyslipidemia. Mechanistically, CIH did not, but HCD did, cause macrophage foam cell formation. NF-κB p50 gene deletion augmented CIH-induced, but not HCD-induced atherosclerosis. These differences reflect the intrinsic differences between the two types of atherosclerosis in terms of pathological nature and underlying mechanisms and support the notion that CIH-induced atherosclerosis is a new paradigm that differs from the classic HCD-induced atherosclerosis.

LPS Down-Regulates Specificity Protein 1 Activity by Activating NF-κB Pathway in Endotoxemic Mice.

BACKGROUND: Specificity protein (Sp) 1 mediates the transcription of a large number of constitutive genes encoding physiological mediators. NF-κB mediates the expression of hundreds of inducible genes encoding pathological mediators. Crosstalk between Sp1 and NF-κB pathways could be pathophysiologically significant, but has not been studied. This study examined the crosstalk between the two pathways and defined the role of NF-κB signaling in LPS-induced down-regulation of Sp1 activity. METHODS AND MAIN FINDINGS: Challenge of wild type mice with samonelia enteritidis LPS (10 mg/kg, i.p.) down-regulated Sp1 binding activity in lungs in a time-dependent manner, which was concomitantly associated with an increased NF-κB activity. LPS down-regulates Sp1 activity by inducing an LPS inducible Sp1-degrading enzyme (LISPDE) activity, which selectively degrades Sp1 protein, resulting in Sp1 down-regulation. Blockade of NF-κB activation in mice deficient in NF-κB p50 gene (NF-κB-KO) suppressed LISPDE activity, prevented Sp1 protein degradation, and reversed the down-regulation of Sp1 DNA binding activity and eNOS expression (an indicator of Sp1 transactivation activity). Inhibition of LISPDE activity using a selective LISPDE inhibitor mimicked the effects of NF-κB blockade. Pretreatment of LPS-challenged WT mice with a selective LISPDE inhibitor increased nuclear Sp1 protein content, restored Sp1 DNA binding activity and reversed eNOS protein down-regulation in lungs. Enhancing tissue level of Sp1 activity by inhibiting NF-κB-mediated Sp1 down-regulation increased tissue level of IL-10 and decreased tissue level of TNF- αin the lungs. CONCLUSIONS: NF-κB signaling mediates LPS-induced down-regulation of Sp1 activity. Activation of NF-κB pathway suppresses Sp1 activity and Sp1-mediated anti-inflammatory signals. Conversely, Sp1 signaling counter-regulates NF-κB-mediated inflammatory response. Crosstalk between NF-κB and Sp1 pathways regulates the balance between pro- and anti-inflammatory cytokines.

Multiple genes identified as targets for 20q13.12-13.33 gain contributing to unfavorable clinical outcomes in patients with hepatocellular carcinoma.

BACKGROUND: Recurrent chromosome 20q gain is implicated in progressive cancer behaviors and has been associated with clinical outcomes in multiple types of cancer; however, its prognostic significance in hepatocellular carcinoma (HCC) and the involved genes remain unclear. METHODS: Array comparative genomic hybridization and expression arrays were used to detect copy number alterations (CNAs) and expression levels, respectively. The associations between CNAs in 20q and outcomes were analyzed on 66 patients, for which the follow-up period was 2.6-73.3 months. One hundred seventeen tumors were further investigated to identify target genes in the potentially outcome-related CNAs. RESULTS: Regional or whole 20q gain was detected in 24 (36.4%) of the 66 HCC cases. The most recurrent gains were 20q11.21-12, 20q12-13.12, 20q13.12-13.33 and 20q13.33. Of the CNAs, 20q13.12-13.33 gain was significantly associated with reduced extrohepatic metastasis-free and overall survival, as well as with elevated postoperative AFP level, tumor vascular invasion and advanced tumor stage. Multivariate Cox analysis identified 20q13.12-13.33 gain as an independent prognostic marker for metastasis (HR 3.73, 95% CI 1.08-12.87) and death (HR 3.00, 95% CI 1.26-7.13). A panel of 19 genes in 20q13.12-13.33 was significantly overexpressed in HCCs with gain compared to HCCs without. High expression (greater than median) for 5 of the 19 genes, DDX27, B4GALT5, RNF114, ZFP64 and PFDN4, correlated significantly with vascular invasion, and high RNF114 expression also with advanced tumor stage. CONCLUSIONS: Gain at 20q13.12-13.33 is a prognostic marker of metastasis and death, and DDX27, B4GALT5, RNF114, ZFP64, and PFDN4 are probable target genes which may be involved together in the unfavorable outcomes of HCC patients.

Resident Endothelial Cells and Endothelial Progenitor Cells Restore Endothelial Barrier Function After Inflammatory Lung Injury.

OBJECTIVE: Disruption of endothelial barrier integrity is a characteristic of many inflammatory conditions. However, the origin and function of endothelial cells (ECs) restoring endothelial barrier function remain unknown. This study defined the roles of resident ECs (RECs) and bone marrow-derived endothelial progenitor cells (BMDEPCs) in endothelial barrier restoration after endotoxemic lung injury. APPROACH AND RESULTS: We generated mice that enable to quantify proliferating RECs or BMDEPCs and also to study the causal link between REC or BMDEPC proliferation and endothelial barrier restoration. Using these mouse models, we showed that endothelial barrier restoration was associated with increased REC and BMDEPC proliferation. RECs and BMDEPCs participate in barrier repair. Immunofluorescence staining demonstrated that RECs proliferate in situ on endothelial layer and that BMDEPCs are engrafted into endothelial layer of lung microvessels at the active barrier repair phase. In lungs, 8 weeks after lipopolysaccharide-induced injury, the number of REC-derived ECs (CD45(-)/CD31(+)/BrdU(+)/rtTA(+)) or BMDEPC-derived ECs (CD45(-)/CD31(+)/eNOS(+)/GFP(+)) increased by 22- or 121-fold, respectively. The suppression of REC or BMDEPC proliferation by blocking REC or BMDEPC intrinsic nuclear factor-κB at the barrier repair phase was associated with an augmented endothelial permeability and impeded endothelial barrier recovery. RECs and BMDEPCs contributed differently to endothelial barrier repair. In lungs, 8 weeks after lipopolysaccharide-induced injury, REC-derived ECs constituted 22%, but BMDEPC-derived ECs constituted only 3.7% of the total new ECs. CONCLUSIONS: REC is a major and BMDEPC is a complementary source of new ECs in endothelial barrier restoration. RECs and BMDEPCs play important roles in endothelial barrier restoration after inflammatory lung injury.

An obligatory role of NF-κB in mediating bone marrow derived endothelial progenitor cell recruitment and proliferation following endotoxemic multiple organ injury in mice.

BACKGROUND: Recruitment of bone marrow derived endothelial progenitor cells (BMDEPCs) alleviates multiple organ injury (MOI) and improves outcomes. However, mechanisms mediating BMDEPC recruitment following septic MOI remain largely unknown. This study characterized the kinetics of BMDEPC recruitment and proliferation and defined the role of NF-κB in regulating BMDEPC recruitment and proliferation. METHODS AND MAIN FINDINGS: Chimeric mice with an intact or disrupted NF-κB p50 gene and BMDEPC-restricted expression of green fluorescent protein were created and injected with LPS (2 mg/kg, i.p.). BMDEPC recruitment and proliferation in multiple organs were quantified. BMDEPC recruitment and proliferation are highly organ-dependent. Lungs had the highest number of BMDEPC recruitment, whereas heart, liver and kidney had only a small fraction of the number of BMDEPCs in lungs. Number of proliferating BMDEPCs was several-fold higher in lungs than in other 3 organs. Kinetically, BMDEPC recruitment into different organs showed different time course profiles. NF-κB plays obligatory roles in mediating BMDEPC recruitment and proliferation. Universal deletion of NF-κB p50 gene inhibited LPS-induced BMDEPC recruitment and proliferation by 95% and 69% in heart. However, the contribution of NF-κB to these regulations varies significantly between organs. In liver, universal p50 gene deletion reduced LPS-induced BMDEPC recruitment and proliferation only by 49% and 35%. NF-κB activities in different tissue compartments play distinct roles. Selective p50 gene deletion either in stromal/parenchymal cells or in BM/blood cells inhibited BMDEPC recruitment by a similar extent. However, selective p50 gene deletion in BM/blood cells inhibited, but in stromal/parenchymal cells augmented BMDEPC proliferation. CONCLUSIONS: BMDEPC recruitment and proliferation display different kinetics in different organs following endotoxemic MOI. NF-κB plays obligatory and organ-dependent roles in regulating BMDEPC recruitment and proliferation. NF-κB activities in different tissue compartments play distinct roles in regulating BMDEPC proliferation.

NF-κB-to-AP-1 switch: a mechanism regulating transition from endothelial barrier injury to repair in endotoxemic mice.

Endothelial barrier disruption is a hallmark of multiple organ injury (MOI). However, mechanisms governing the restoration of endothelial barrier function are poorly understood. Here, we uncovered an NF-κB-to-AP-1 switch that regulates the transition from barrier injury to repair following endotoxemic MOI. Endothelial NF-κB mediates barrier repair by inhibiting endothelial cell (EC) apoptosis. Blockade of endothelial NF-κB pathway activated the activator protein (AP)-1 pathway (NF-κB-to-AP-1 switch), which compensated for the anti-apoptotic and barrier-repair functions of NF-κB. The NF-κB-to-AP-1 switch occurred at 24 hours (injury to repair transition phase), but not at 48 hours (repair phase) post-LPS, and required an inflammatory signal within the endothelium. In the absence of an inflammatory signal, the NF-κB-to-AP-1 switch failed, resulting in enhanced EC apoptosis, augmented endothelial permeability, and impeded transition from barrier injury to recovery. The NF-κB-to-AP-1 switch is a protective mechanism to ensure timely transition from endothelial barrier injury to repair, accelerating barrier restoration following MOI.

Ulinastatin activates haem oxygenase 1 antioxidant pathway and attenuates allergic inflammation.

BACKGROUND AND PURPOSE: Ulinastatin (UTI), a serine protease inhibitor, was recently found to have an anti-inflammatory action. However, the mechanisms mediating this anti-inflammatory effect are not well understood. This study tested the hypothesis that UTI suppresses allergic inflammation by inducing the expression of haem oxygenase 1 (HO1). EXPERIMENTAL APPROACH: Control mice and mice sensitized (on days 1, 9 and 14) and challenged (on days 21 to 27) with ovalbumin (OVA) were treated with UTI. The effects of UTI on basal expression of HO1 and that induced by OVA challenge were examined. The involvement of UTI-induced HO1 expression in anti-inflammatory and antioxidant effects of UTI was also evaluated. KEY RESULTS: UTI markedly increased basal HO1 protein expression in lungs of control mice in a time- and dose-dependent manner, and augmented HO1 protein expression induced by OVA. The up-regulation of HO1 mediated by UTI in sensitized and OVA-challenged mice was associated with reduced airway inflammation, alleviated tissue injury, reduced oxidant stress and enhanced antioxidant enzyme activities. Inhibition of HO1 activity using HO1 inhibitor, zinc protoporphyrin, attenuated inhibitory effects of UTI on inflammation and oxidant stress, and its stimulant effects on antioxidant enzyme activities. Mechanistic analysis showed that UTI increased nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2), stimulated Nrf2 DNA binding activity and concomitantly up-regulated HO1 mRNA expression. CONCLUSIONS AND IMPLICATIONS: UTI is a potent and naturally occurring inducer of HO1 expression. HO1 up-regulation contributes significantly to the anti-inflammatory and organ-protective effects of UTI, which has important research and therapeutic implications.

Intermedin modulates hypoxic pulmonary vascular remodeling by inhibiting pulmonary artery smooth muscle cell proliferation.

BACKGROUND: Hypoxic pulmonary arterial hypertension (PAH) is a disabling disease with limited treatment options. Hypoxic pulmonary vascular remodeling is a major cause of hypoxic PAH. Pharmacological agents that can inhibit the remodeling process may have great therapeutic value. OBJECTIVE: To examine the effect of intermedin (IMD), a new calcitonin gene-related peptide family of peptide, on hypoxic pulmonary vascular remodeling. METHODS: Rats were exposed to normoxia or hypoxia (∼10% O(2)), or exposed to hypoxia and treated with IMD, administered by an implanted mini-osmotic pump (6.5 µg/rat/day), for 4 weeks. The effects of IMD infusion on the development of hypoxic PAH and right ventricle (RV) hypertrophy, on pulmonary vascular remodeling, on pulmonary artery smooth muscle cell (PASMC) proliferation and apoptosis, and on the activations of l-arginine nitric oxide (NO) pathway and endoplasmic reticulum stress apoptotic pathway were examined. RESULTS: Rats exposed to hypoxia developed PAH and RV hypertrophy. IMD treatment alleviated PAH and prevented RV hypertrophy. IMD inhibited hypoxic pulmonary vascular remodeling as indicated by reduced wall thickness and increased lumen diameter of pulmonary arterioles, and decreased muscularization of distal pulmonary vasculature in hypoxia-exposed rats. IMD treatment inhibited PASMC proliferation and promoted PASMC apoptosis. IMD treatment increased tissue level of constitutive NO synthase activity and tissue NO content in lungs, and enhanced l-arginine uptake into pulmonary vascular tissues. IMD treatment increased cellular levels of glucose-regulated protein (GRP) 78 and GRP94, two major markers of endoplasmic reticulum (ER) stress, and increased caspase-12 expression, the ER stress-specific caspase, in lungs and cultured PASMCs. CONCLUSIONS: These results demonstrate that IMD treatment attenuates hypoxic pulmonary vascular remodeling, and thereby hypoxic PAH mainly by inhibiting PASMC proliferation. Promotion of PASMC apoptosis may also contribute to the inhibitory effect of IMD. Activations l-arginine-NO pathway and of ER stress-specific apoptosis pathway could be the mechanisms mediating the anti-proliferative and pro-apoptotic effects of IMD.