Long non-coding RNA Small Nucleolar RNA Host Gene 4 ameliorates cigarette smoke-induced proliferation, apoptosis, inflammation, and airway remodeling in alveolar epithelial cells through the modulation of the mitogen-activated protein kinase signaling pathway via the microRNA-409-3p/Four and a Half LIM Domains 1 axis.

The long non-coding RNA (lncRNA) Small Nucleolar RNA Host Gene 4 (SNHG4) has been demonstrated to be significantly downregulated in various inflammatory conditions, yet its role in chronic obstructive pulmonary disease (COPD) remains elusive. This study aims to elucidate the biological function of SNHG4 in COPD and to unveil its potential molecular targets. Our findings reveal that both SNHG4 and Four and a Half LIM Domains 1 (FHL1) were markedly downregulated in COPD, whereas microRNA-409-3p (miR-409-3p) was upregulated. Importantly, SNHG4 exhibited a negative correlation with inflammatory markers in patients with COPD, but a positive correlation with forced expiratory volume in 1s percentage (FEV1%). SNHG4 distinguished COPD patients from non-smokers with high sensitivity, specificity, and accuracy. Overexpression of SNHG4 ameliorated cigarette smoke extract (CSE)-mediated inflammation, apoptosis, oxidative stress, and airway remodeling in 16HBE bronchial epithelial cells. These beneficial effects of SNHG4 overexpression were reversed by the overexpression of miR-409-3p or the silencing of FHL1. Mechanistically, SNHG4 competitively bound to miR-409-3p, mediating the expression of FHL1, and consequently improving inflammation, apoptosis, oxidative stress, and airway remodeling in 16HBE cells. Additionally, SNHG4 regulated the miR-409-3p/FHL1 axis to inhibit the activation of the mitogen-activated protein kinase (MAPK) pathway induced by CSE. In a murine model of COPD, knockdown of SNHG4 exacerbated CSE-induced pulmonary inflammation, apoptosis, and oxidative stress. In summary, our data affirm that SNHG4 mitigates pulmonary inflammation, apoptosis, and oxidative damage mediated by COPD through the regulation of the miR-409-3p/FHL1 axis.

Vaporization of perfluorocarbon attenuates sea-water-drowning-induced acute lung injury by deactivating the NLRP3 inflammasomes in canines.

Seawater-drowning-induced acute lung injury (SD-ALI) is a life-threatening disorder characterized by increased alveolar-capillary permeability, an excessive inflammatory response, and refractory hypoxemia. Perfluorocarbons (PFCs) are biocompatible compounds that are chemically and biologically inert and lack toxicity as oxygen carriers, which could reduce lung injury in vitro and in vivo. The aim of our study was to explore whether the vaporization of PFCs could reduce the severity of SD-ALI in canines and investigate the underlying mechanisms. Eighteen beagle dogs were randomly divided into three groups: the seawater drowning (SW), perfluorocarbon (PFC), and control groups. The dogs in the SW group were intratracheally administered seawater to establish the animal model. The dogs in the PFC group were treated with vaporized PFCs. Probe-based confocal laser endomicroscopy (pCLE) was performed at 3 h. The blood gas, volume air index (VAI), pathological changes, and wet-to-dry (W/D) lung tissue ratios were assessed. The expression of heme oxygenase-1 (HO-1), nuclear respiratory factor-1 (NRF1), and NOD-like receptor family pyrin domain containing-3 (NLRP3) inflammasomes was determined by means of quantitative real-time polymerase chain reaction (qRT-PCR) and immunological histological chemistry. The SW group showed higher lung injury scores and W/D ratios, and lower VAI compared to the control group, and treatment with PFCs could reverse the change of lung injury score, W/D ratio and VAI. PFCs deactivated NLRP3 inflammasomes and reduced the release of caspase-1, interleukin-1ß (IL-1ß), and interleukin-18 (IL-18) by enhancing the expression of HO-1 and NRF1. Our results suggest that the vaporization of PFCs could attenuate SD-ALI by deactivating NLRP3 inflammasomes via the HO-1/NRF1 pathway.

Associations of nirmatrelvir-ritonavir treatment with death and clinical improvement in hospitalized patients with COVID-19 during the Omicron wave in Beijing, China: a multicentre, retrospective cohort study.

BACKGROUND: The effectiveness of nirmatrelvir-ritonavir has mainly been shown in non-hospitalized patients with mild-to-moderate coronavirus disease 2019 (COVID-19). The real-world effectiveness of nirmatrelvir-ritonavir urgently needs to be determined using representative in-hospital patients with COVID-19 during the Omicron wave of the pandemic. METHODS: We performed a multicentre, retrospective study in five Chinese PLA General Hospital medical centers in Beijing, China. Patients hospitalized with COVID-19 from 10 December 2022 to 20 February 2023 were eligible for inclusion. A 1:1 propensity score matching was performed between the nirmatrelvir-ritonavir group and the control group. RESULTS: 1010 recipients of nirmatrelvir-ritonavir and 1010 matched controls were finally analyzed after matching. Compared with matched controls, the nirmatrelvir-ritonavir group had a lower incidence rate of all-cause death (4.6/1000 vs. 6.3/1000 person-days, p = 0.013) and a higher incidence rate of clinical improvement (47.6/1000 vs. 45.8/1000 person-days, p = 0.012). Nirmatrelvir-ritonavir was associated with a 22% lower all-cause mortality and a 14% higher incidence of clinical improvement. Initiation of nirmatrelvir-ritonavir within 5 days after symptom onset was associated with a 50% lower mortality and a 26% higher clinical improvement rate. By contrast, no significant associations were identified among patients receiving nirmatrelvir-ritonavir treatment more than 5 days after symptom onset. Nirmatrelvir-ritonavir was also associated with a 50% increase in survival days and a 12% decrease in days to clinical improvement. CONCLUSION: Among hospitalized patients with COVID-19 during the Omicron wave in Beijing, China, the early initiation of nirmatrelvir-ritonavir was associated with clinical benefits of lowering mortality and improving clinical recovery.

Paralemmin-3 augments lipopolysaccharide-induced acute lung injury with M1 macrophage polarization via the notch signaling pathway.

BACKGROUND: Acute lung injury (ALI) involves severe lung damage and respiratory failure, which are accompanied by alveolar macrophage (AM) activation. The aim of this article is to verify the influence of paralemmin-3 (PALM3) on alveolar macrophage (AM) polarization in ALI and the underlying mechanism of action. METHODS: An ALI rat model was established by successive lipopolysaccharide (LPS) inhalations. The influence of PALM3 on the survival rate, severity of lung injury, and macrophage polarization was analyzed. Furthermore, we explored the underlying mechanism of PALM3 in regulating macrophage polarization. RESULTS: PALM3 overexpression increased mortality of ALI rats, augmented lung pathological damage, and promoted AM polarization toward M1 cells. Conversely, PALM3 knockdown had the opposite effects. Mechanistically, PALM3 might promote M1 polarization by acting as an adaptor to facilitate transduction of Notch signaling. CONCLUSION: PALM3 aggravates lung injury and induces macrophage polarization toward M1 cells by activating the Notch signaling pathway in LPS-induced ALI, which may shed light on ALI/ARDS treatments.

Probe-based confocal laser endomicroscopy for evaluating high-altitude pulmonary edema in canines.

Background: Real-time assessment of high-altitude pulmonary edema (HAPE) remains a challenge. Probe-based confocal laser microscopy (pCLE) allows a real-time in vivo visualization of the alveoli. This study aimed to develop a new non-invasive method for analyzing microscopic images in a canine model of HAPE using pCLE. Materials and methods: This was a prospective, controlled animal study in adult male beagle dogs randomized to control and HAPE groups. The HAPE group was exposed to a high altitude of 6000 m for 48 h. The blood gas levels, lung morphological changes, infectious factors, and lung wet-to-dry ratio were analyzed in different groups. The pCLE images were described based on the volume air index (VAI), which applies an integral over specific signal intensities. Results: The lung wet-to-dry weight ratio and injury scores in the HAPE group were significantly increased compared with those of the control group. The levels of infectious factors interleukin-1 beta, tumor necrosis factor-alpha, and interleukin-6 were significantly increased in the HAPE group compared with those in the control group. VAI was significantly decreased in the HAPE group. Conclusion: pCLE is a potential adjudicative bronchoscopic imaging technique for assessing HAPE. VAI may be acquired from quantitative parameters in the analysis of images.

EPN3 plays oncogenic role in non-small cell lung cancer by activating the JAK1/2-STAT3 pathway.

The effect of Epsin 3 (EPN3) on non-small cell lung cancer (NSCLC) has not yet been clearly elucidated. This study identified the exact function of EPN3 on NSCLC progression. EPN3 expression in NSCLC patients were analyzed based on the Cancer Genome Atlas database. Kaplan-Meier analysis was implemented to research the effect of EPN3 on patients' survival. EPN3 expression in clinical tissues of 62 NSCLC cases was monitored by real-time quantitative reverse transcription polymerase chain reaction, immunohistochemistry and Western blot. A549 and H1299 cells were transfected with EPN3 shRNA and treated by RO8191 (20 µM). Proliferation was researched by cell counting kit-8 and 5-ethnyl-2 deoxyuridine assays. Apoptosis was monitored by flow cytometry. Migration and invasion was assessed by Transwell experiment. EPN3 effect on A549 cell in vivo growth was researched using nude mice. RO8191 (200 µg) was intratumoral injected into mice. Immunohistochemistry and Western blot was implemented to monitor protein expression in cells and xenograft tumor tissues. EPN3 was abnormally up-regulated in NSCLC patients and cells, indicating a lower overall survival. Loss of EPN3 weakened proliferation, migration and invasion, induced apoptosis, and repressed epithelial-mesenchymal transition in NSCLC cells. Loss of EPN3 inactivated the JAK1/2-STAT3 pathway in NSCLC cells. RO8191 treatment reversed the inhibition of EPN3 knockdown on the malignant phenotype of NSCLC cells. RO8191 intratumoral injection reversed the suppression of EPN3 silencing on NSCLC cell in vivo growth. EPN3 acted as an oncogene in NSCLC via activating the JAK1/2-STAT3 pathway. EPN3 may be a promising target for NSCLC treatment.

LncRNA SNHG3 Promotes Proliferation and Metastasis of Non-Small-Cell Lung Cancer Cells Through miR-515-5p/SUMO2 Axis.

Lung cancer is a global disease and a major cause of cancer-related mortality worldwide. Accumulated studies have confirmed the essential role of long non-coding RNAs (lncRNAs) in the occurrence and development of cancers. Meanwhile, there have been reports concerning the role of Small Nucleolar RNA Host Gene 3 (SNHG3) in various cancers. However, there are so far few studies on the function and mechanism of SNHG3 in lung cancer. In the present study, SNHG3 was found to be highly expressed in lung cancer tissues and cells. Downregulation of SNHG3 could inhibit cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) process. In addition, SNHG3 was found to have the ability to bind to miR-515-5p. Furthermore, Small Ubiquitin Like Modifier 2 (SUMO2) was identified to be the downstream target of miR-515-5p, which was negatively correlated with miR-515-5p expression. SNHG3 could positively regulate SUMO2 expression by sponging miR-515-5p. In addition, the rescue experiment showed that simultaneous transfection of miR-515-5p or SUMO2 siRNA could reverse the effect of SNHG3 expression on cell proliferation and metastasis. Collectively, our study demonstrates that SNHG3 can act on miR-515-5p in the form of competitive endogenous RNA (ceRNA) to regulate SUMO2 positively and thus affect the proliferation and metastasis of NSCLC cells. Findings in our study support that SNHG3/miR-515-5p/SUMO2 regulatory axis may become a potential therapeutic target for lung cancer.

PFKFB4 promotes lung adenocarcinoma progression via phosphorylating and activating transcriptional coactivator SRC-2.

BACKGROUND: To investigate the role and its potential mechanism of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 4 (PFKFB4) in lung adenocarcinoma. METHODS: Co-immunoprecipitation was performed to analyze the interaction between PFKFB4 and SRC-2. Western blot was used to investigate the phosphorylation of steroid receptor coactivator-2 (SRC-2) on the condition that PFKFB4 was knockdown. Transcriptome sequencing was performed to find the downstream target of SRC-2. Cell Counting Kit-8 (CCK-8) assay, transwell assay and transwell-matrigel assay were used to examine the proliferation, migration and invasion abilities in A549 and NCI-H1975 cells with different treatment. RESULTS: In our study we found that PFKFB4 was overexpressed in lung adenocarcinoma associated with SRC family protein and had an interaction with SRC-2. PFKFB4 could phosphorylate SRC-2 at Ser487, which altered SRC-2 transcriptional activity. Functionally, PFKFB4 promoted lung adenocarcinoma cells proliferation, migration and invasion by phosphorylating SRC-2. Furthermore, we identified that CARM1 was transcriptionally regulated by SRC-2 and involved in PFKFB4-SRC-2 axis on lung adenocarcinoma progression. CONCLUSIONS: Our research reveal that PFKFB4 promotes lung adenocarcinoma cells proliferation, migration and invasion via enhancing phosphorylated SRC-2-mediated CARM1 expression.

Macrophage polarization and its role in the pathogenesis of acute lung injury/acute respiratory distress syndrome.

PURPOSE: Macrophages are highly plastic cells. Under different stimuli, macrophages can be polarized into several different subsets. Two main macrophage subsets have been suggested: classically activated or inflammatory (M1) macrophages and alternatively activated or anti-inflammatory (M2) macrophages. Macrophage polarization is governed by a highly complex set of regulatory networks. Many recent studies have shown that macrophages are key orchestrators in the pathogenesis of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) and that regulation of macrophage polarization may improve the prognosis of ALI/ARDS. A further understanding of the mechanisms of macrophage polarization is expected to be helpful in the development of novel therapeutic targets to treat ALI/ARDS. Therefore, we performed a literature review to summarize the regulatory mechanisms of macrophage polarization and its role in the pathogenesis of ALI/ARDS. METHODS: A computer-based online search was performed using the PubMed database and Web of Science database for published articles concerning macrophages, macrophage polarization, and ALI/ARDS. RESULTS: In this review, we discuss the origin, polarization, and polarization regulation of macrophages as well as the role of macrophage polarization in various stages of ARDS. According to the current literature, regulating the polarized state of macrophages might be a potential therapeutic strategy against ALI/ARDS.

Coculture with bone marrow­derived mesenchymal stem cells attenuates inflammation and apoptosis in lipopolysaccharide­stimulated alveolar epithelial cells via enhanced secretion of keratinocyte growth factor and angiopoietin­1 modulating the Toll­like receptor­4 signal pathway.

Acute lung injury (ALI) is a common, costly and potentially lethal disease with characteristics of alveolar­capillary membrane disruption, pulmonary edema and impaired gas exchange due to increased apoptosis and pulmonary inflammation. There is no effective and specific therapy for ALI; however, mesenchymal stem cells (MSCs) have been demonstrated to be a potential option. Lipopolysaccharide (LPS) is a highly proinflammatory molecule that is used to mimic an in vivo inflammatory and damaged state in vitro. The present study investigated the effect of bone marrow­derived MSCs on an LPS­induced alveolar epithelial cell (A549 cell line) injury and its underlying mechanisms by a Transwell system. It was identified that a high LPS concentration caused a decrease in cell viability, increases in apoptosis, inflammatory cytokine release and NF­κB activity, disruption of the caspase­3/Bcl­2 ratio, upregulation of Toll­like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and toll­interleukin­1 receptor domain­containing adaptor inducing interferon (TRIF) expression, and facilitation of TLR4/MyD88 and TLR4/TRIF complex formation in A549 cells. Coculture with MSCs attenuated all of these activities induced by LPS in A549 cells. In addition, an increased level of keratinocyte growth factor (KGF) and angiopoietin­1 (ANGPT1) secretion from MSCs was observed under inflammatory stimulation. KGF and/or ANGPT1 neutralizing antibodies diminished the beneficial effect of MSC conditioned medium. These data suggest that MSCs alleviate inflammatory damage and cellular apoptosis induced by LPS in A549 cells by modulating TLR4 signals. These changes may be partly associated with an increased secretion of KGF and ANGPT1 from MSCs under inflammatory conditions. These data provide the basis for development of MSC­based therapies for ALI.

Mesenchymal stem cells overexpressing heme oxygenase-1 ameliorate lipopolysaccharide-induced acute lung injury in rats.

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are common and potentially lethal clinical syndromes characterized by acute respiratory failure resulting from excessive pulmonary inflammation, noncardiogenic pulmonary edema, and alveolar-capillary barrier disruption. At present, there is no effective and specific therapy for ALI/ARDS. Mesenchymal stem cells (MSCs) have well-known therapeutic potential in patients with ALI/ARDS. Heme oxygenase-1 (HO-1), a cytoprotective enzyme, possesses antioxidative, anti-inflammatory, and antiapoptotic effects. Thus, a combination of MSC transplantation with HO-1 delivery may have an additional protective effect against ALI/ARDS. This study investigated the effect of HO-1-modified bone-marrow-derived MSCs (MSCs-HO-1) on lipopolysaccharide (LPS)-induced ALI and its underlying mechanisms. We established MSCs-HO-1 through lentiviral transduction. The ALI rat model was established by successive LPS inhalations following injection with MSCs-HO-1. The survival rate, histological changes in the lungs, total protein concentration and neutrophil counts in bronchoalveolar lavage fluid, lung wet/dry weight ratio, cytokine levels in serum and lungs, nuclear transcription factor-κB activity, and protein expression of Toll-like receptor 4 signaling adaptors were examined. Furthermore, the cell viability, apoptosis, and paracrine activity of MSCs-HO-1 were examined under inflammatory stimuli in vitro. MSCs-HO-1 injection improved these parameters compared with primary unmodified MSCs. Moreover, MSCs-HO-1 had superior prosurvival and antiapoptotic properties and enhanced paracrine functions in vitro. Therefore, MSCs-HO-1 exert an enhanced protective effect to alleviate LPS-induced ALI in rats, and the mechanisms may be partially associated with superior prosurvival, antiapoptosis, and enhanced paracrine functions of MSCs-HO-1. These findings provide a novel insight into MSC-based therapeutic strategies for treating ALI/ARDS.

[Therapeutic effects of different doses of methylprednisolone on smoke inhalation-induced acute lung injury in rats].

OBJECTIVE: To investigate the therapeutic effect of different doses of methylprednisolone (MP) in smoke inhalation-induced acute lung injury (SI-ALI). METHODS: Adult male Sprague-Dawley (SD) rats were divided into control group (group A, n = 6), smoke inhalation group (group B, smoke inhalation 30 minutes, n = 30) and smoke + MP 40, 4, 0.4 mg/kg intervention group (groups C, D, E; intraperitoneal injection of MP at 1 hour before smoke inhalation, n = 30) according to random number table method. The survival status of rats in each group was observed at 24 hours, and murine smoke inhalation induced trauma score (MSITS) according to the symptoms and signs of rats at 3 hours after smoke inhalation were scored. The blood of abdominal aorta of rats was collected. Then the rats were sacrificed to harvest bronchoalveolar lavage fluid (BALF) and lung tissue. The levels of interleukin (IL-6, IL-17a) in plasma and BALF were detected by enzyme linked immunosorbent assay (ELISA); the total number of white blood cells and the proportion of leukocytes or macrophages in BALF were calculated; the histopathological changes of lung were observed and the lung injury score was given; the expression of myeloperoxidase (MPO) and high mobility group protein B1 (HMGB1) in lung tissue were detected by Western Blot. RESULTS: The 24-hour survival rate of group B rats was 33.67%. The survival rate of groups C, D and E (65.73%, 85.17%, 60.07%) were significantly higher than that of group B (all P < 0.05), and the survival rate of group D was significantly higher than that of groups C and E. Diffuse inflammatory cell infiltration, intra-alveolar hemorrhage and a large amount of edema fluid were seen in the lung tissue of group B; and the lung injury score was significantly higher than that of group A. Compared with group B, the lung injury in different doses of MP group were decreased to different degrees, while the lung injury scores in groups C and D were significantly decreased (3.31±1.37, 2.62±0.98 vs. 5.52±0.97, both P < 0.01); correlation analysis showed that MSITS score was significantly and positively correlated with lung injury score (r = 0.862, P < 0.001). The levels of plasma inflammatory factors and BALF protein, inflammatory cells and inflammatory factors, and the expression of MPO, HMGB1 in group B were significantly higher than those in group A. Compared with group B, the levels of inflammatory factors in plasma, and protein content, inflammatory cells and inflammatory factors in BALF in different doses of MP group were decreased to different degrees, with significant differences in groups C and D [plasma: IL-17a (pg/L): 49.28±27.12, 36.57±16.52 vs. 191.79±88.21; IL-6 (ng/L): 206.47±109.96, 197.52±113.86 vs. 669.00±299.60; BALF: protein content (mg/L): 892.0±164.5, 566.1±120.9 vs. 1 838.0±145.8; white blood cell count (×109/L): 5.40±1.67, 2.81±1.20 vs. 9.02±2.06; neutrophil ratio: 0.315±0.081, 0.273±0.080 vs. 0.590±0.096; IL-17a (ng/L): 22.63±8.62, 18.92±8.43 vs. 43.31±19.17; IL-6 (ng/L): 156.49±46.94, 123.66±64.91 vs. 253.43±80.03; all P < 0.01]; in addition, the expression of MPO and HMGB1 protein in lung tissues of MP groups with different doses were significantly decreased, the expression of MPO in group D was significantly lower than that in group E [MPO/ß-actin (fold increase from group A): 2.14±0.97 vs. 4.35±0.87, P < 0.01], the expression of HMGB1 in groups C and D were significantly lower than that in group E [HMGB1/ß-actin (fold increase from group A): 1.77±0.73, 1.23±0.67 vs. 3.65±1.08, both P < 0.05]. CONCLUSIONS: MP can significantly improve the survival rate of SI-ALI rats and reduce the acute pulmonary and systemic inflammatory response. The MP effect of 4 mg/kg was better than 40 mg/kg and 0.4 mg/kg.

Mesenchymal Stem Cells Modified with Heme Oxygenase-1 Have Enhanced Paracrine Function and Attenuate Lipopolysaccharide-Induced Inflammatory and Oxidative Damage in Pulmonary Microvascular Endothelial Cells.

BACKGROUND/AIMS: Bone marrow-derived mesenchymal stem cell (BM-MSC) transplantation has therapeutic effects on endothelial damage during acute lung injury (ALI). Heme oxygenase-1 (HO-1) can restore homeostasis and implement cytoprotective defense functions in many pathologic states. Therefore, we explored whether transduction of HO-1 into BM-MSCs (MSCs-HO-1) would have an increased beneficial effect on lipopolysaccharide (LPS)-induced inflammatory and oxidative damage in human pulmonary microvascular endothelial cells (PVECs). METHODS: MSCs were isolated from rat bone marrow and transfected with the HO-1 gene by a lentivirus vector. The phenotype and multilineage differentiation of MSCs were assessed. MSCs or MSCs-HO-1 were co-cultured with PVECs using a transwell system, and LPS was added to induce PVEC injury. The production of reactive oxygen species (ROS), and the activities of lipid peroxide (LPO), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in PVECs were determined by flow cytometry and colorimetric assays, respectively. The levels of human PVEC-derived tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß and IL-6 in the supernatants of the co-culture system, and the activity of nuclear transcription factor-κB and NF-E2-related factor 2 (Nrf2) in PVECs were examined by enzyme-linked immunosorbent assay (ELISA). The mRNA expression of TNF-α, IL-1ß and IL-6 in PVECs was detected by quantitative real-time polymerase chain reaction (qRT-PCR), HO-1 expression and enzymatic activity in PVECs and the influence of zinc protoporphyrin (ZnPP) or HO-1 small interfering RNA on the above inflammatory and oxidative stress markers were evaluated. In addition, the expression of rat MSC-derived hepatocyte growth factor (HGF) and IL-10 was determined by ELISA and qRT-PCR. RESULTS: MSCs showed no significant changes in phenotype or multilineage differentiation after transduction. LPS strongly increased the production of inflammatory and oxidative stress indicators, as well as decreased the levels of antioxidant components and the activity of Nrf2 in PVECs. MSC co-cultivation ameliorated these detrimental effects in PVECs and MSCs-HO-1 further improved the damage to PVECs induced by LPS when compared with MSCs alone. The beneficial effects of MSCs-HO-1 were dependent on HO-1 overexpression and may be attributed to the enhanced paracrine production of HGF and IL-10. CONCLUSION: MSCs-HO-1 have an enhanced ability to improve LPS-induced inflammatory and oxidative damage in PVECs, and the mechanism may be partially associated with the enhanced paracrine function of the stem cells. These data encourage further testing of the beneficial effects of MSCs-HO-1 in ALI animal models.

Paralemmin-3 contributes to lipopolysaccharide-induced inflammatory response and is involved in lipopolysaccharide-Toll-like receptor-4 signaling in alveolar macrophages.

Alveolar macrophages (AMs) are the first line of defense against foreign stimulation in alveoli, and they participate in inflammatory responses during acute lung injury (ALI). Previous studies indicated that paralemmin-3 (PALM3) expression is induced by lipopolysaccharides (LPS) and may be involved in LPS-Toll-like receptor 4 (TLR4) signaling in alveolar epithelial cells. The aim of the present study was to investigate the effect of PALM3 on LPS-induced inflammation and its underlying mechanisms in rat AMs. For this purpose, the authors detected the expression of PALM3 in AMs by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting following LPS stimulation. Following this, a recombinant adenovirus expressing short hairpin RNA (shRNA) for PALM3 was constructed, as well as a recombinant adenovirus carrying the rat PALM3 gene to modulate the expression of PALM3 in rat AMs. At 48 h after transfection, the PALM3 expression in AMs was detected by RT-qPCR and western blotting. The levels of several cytokines and the activity of nuclear factor-κB and interferon regulatory factor 3 in AMs were measured after LPS stimulation. The localization of PALM3 and LPS-TLR4 signaling adaptor molecules in AMs was analyzed by confocal microscopy, and the physical interactions of PALM3 with these adaptors were assessed by co-immunoprecipitation assays. LPS induced PALM3 expression in AMs and that PALM3 expression promoted the LPS-induced inflammatory response, while PALM3 downregulation suppressed the LPS-induced inflammatory response in AMs. In addition, the results demonstrated that PALM3 could interact with TLR4, myeloid differentiation factor 88, interleukin (IL)-1 receptor associated kinase-1, tumor necrosis factor receptor associated factor-6, and Toll-IL-1 receptor containing adapter molecule-2 in AMs after LPS stimulation. These results suggested that PALM3 contributes to the LPS-induced inflammatory response and participates in LPS-TLR4 signaling in AMs. These data may provide the basis for the development of novel targeted therapeutic strategies of treating ALI.

Downregulation of Paralemmin-3 Ameliorates Lipopolysaccharide-Induced Acute Lung Injury in Rats by Regulating Inflammatory Response and Inhibiting Formation of TLR4/MyD88 and TLR4/TRIF Complexes.

Previous studies have demonstrated paralemmin-3 (PALM3) participates in Toll-like receptor (TLR) signaling. This study investigated the effect of PALM3 knockdown on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and its underlying mechanisms. We constructed a recombinant adenoviral vector containing short hairpin RNA for PALM3 to knockdown PALM3 expression. A transgene-free adenoviral vector was used as a negative control. The ALI rat model was established by LPS peritoneal injection at 48-h post-transfection. Results showed that downregulation of PALM3 improved the survival rate, attenuated lung pathological changes, alleviated pulmonary edema, lung vascular leakage and neutrophil infiltration, inhibited the production of proinflammatory cytokines and activation of nuclear factor κB and interferon ß regulatory factor 3, and promoted the secretion of anti-inflammatory cytokine interleukin-10 and expression of suppressor of cytokine signaling-3 in the ALI rat model. However, PALM3 knockdown had no effect on TLR4, myeloid differentiation factor 88 (MyD88), and Toll-interleukin-1 receptor domain-containing adaptor inducing interferon ß (TRIF) expression. Moreover, PALM3 knockdown reduced the interaction of TLR4 with MyD88 or TRIF induced by LPS in rat lungs. Therefore, the downregulation of PALM3 protected rats from LPS-induced ALI and its mechanisms were partially associated with the modulation of inflammatory responses and inhibition of TLR4/MyD88 and TLR4/TRIF complex formation.

[Evaluation of bronchial mucosa involvement in sarcoidosis patients using ¹8F-FDG PET-CT].

OBJECTIVE: To explore the value of ¹8F-FDG PET-CT in evaluating bronchial mucosa involvement in patients with saroidosis. METHODS: A retrospective analysis was conducted among 6 sarcoidosis patients with and 14 patients without bronchial mucosa involvement to collect the data including the standard uptake value (SUVMax/Mean) of ¹8F-FDG, serum angiotensin converting enzyme (sACE), and proportion of lymphocytes and CD4⁺/CD8 ⁺ T lymphocyte ratio in bronchoalveolar lavage fluid (BALF). RESULTS: The lung focal SUV(Max/Mean) was higher in patients with bronchial mucosa involvement than those without (7.04 ± 5.83/5.00 ± 4.69 vs 5.68 ± 3.66/3.82 ± 2.39), but such differences were not statistically significant (P=0.565/0.495). The SUV(Max/Mean) of the hilum of the lung and the mediastina lymph nodes were significantly higher in patients with bronchial mucosa involvement (13.28 ± 5.57/10.48 ± 4.43 vs 6.20 ± 1.77/4.52 ± 1.43, P=0.0003/0.0002; 13.84 ± 4.35/9.69 ± 2.74 vs 7.16 ± 2.52/5.28 ± 1.77, P=0.0004/0.0004). The level of sACE and CD4⁺/CD8 ⁺ T lymphocyte ratio in BALF were also significantly higher in patients with bronchial mucosa involvement (60.58 ± 16.3 vs 49.16 ± 13.3 IU/L, P=0.045; 7.30 ± 5.0 vs 2.90 ± 3.1, P=0.026). The proportion of lymphocytes in BALF was comparable between the patients with and without bronchial mucosa involvement (44.10 ± 10.3% vs 35.30 ± 12.5%, P=0.148). CONCLUSIONS: For patients with saroidosis, ¹8F-FDG PET-CT is useful in evaluating bronchial mucosa involvement, which is one of the key features of active sarcoidosis.

[Experimental treatment of acute lung injury caused by inundation of thoracic cavity by seawater following open chest wound].

OBJECTIVE: To study the effects of lung protective ventilation and pentoxifylline (PTX) on acute lung injury (ALI) caused by open chest wound with seawater inundation of the thoracic cavity. METHODS: A model of ALI caused by open chest wound and seawater inundation of thoracic cavity was reproduced in dogs. Twenty-four healthy dogs were randomly divided into four groups: no-treatment group (group A), ordinary treatment group (group B), lung protective ventilation treatment group (group C), and lung protective ventilation and PTX treatment group (group D). The parameters of hemodynamics, arterial blood gas analysis, plasma osmotic pressure and serum electrolytes in dogs were determined at 0 and 6 hours after injury and at 2 and 4 hours after treatment. Blood samples and bronchoalveolar lavage fluid (BALF) were collected to assess the changes in cytokines including tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and IL-8. RESULTS: The arterial oxygen partial pressure (PaO(2)) and oxygenation index (PaO(2)/FiO(2)) in group B were still lower than normal values at 2 and 4 hours after treatment, but those parameters in group C and group D distinctly recovered. The parameters of hemodynamics, plasma osmotic pressure and serum electrolytes were all normalized in group B, C and D at 2 and 4 hours after treatment compared with those in group A. The levels of TNF-alpha in peripheral blood in group C and the TNF-alpha and IL-8 levels in peripheral blood and IL-6, IL-8 levels in BALF in group D were significantly lower than those in group A and group B after treatment. The TNF-alpha in peripheral blood and IL-8 levels in BALF in group D were also significantly lower than those in group C after treatment. CONCLUSION: Lung protective ventilation is an effective method in the treatment of ALI caused by open chest wound with inundation of seawater in thoracic cavity. PTX can inhibit inflammatory reaction in the lung and peripheral blood.