Inflammatory lung injury is associated with endothelial cell mitochondrial fission and requires the nitration of RhoA and cytoskeletal remodeling

Higher levels of extracellular nicotinamide phosphoribosyltransferase (eNAMPT), a TLR4 agonist, are associated with poor clinical outcomes in sepsis-induced acute lung injury (ALI). Little is known regarding the mechanisms by which eNAMPT is involved in ALI. Our recent work has identified a crucial role for mitochondrial dysfunction in ALI. Thus, this study aimed to determine if eNAMPT-mediated inflammatory injury is associated with the loss of mitochondrial function. Our data show that eNAMPT disrupted mitochondrial bioenergetics. This was associated with cytoskeleton remodeling and the loss of endothelial barrier integrity. These changes were associated with enhanced mitochondrial fission and blocked when Rho-kinase (ROCK) was inhibited. The increases in mitochondrial fission were also associated with the nitration-mediated activation of the small GTPase activator of ROCK, RhoA. Blocking RhoA nitration decreased eNAMPT-mediated mitochondrial fission and endothelial barrier dysfunction. The increase in fission was linked to a RhoA-ROCK mediated increase in Drp1 (dynamin-related protein 1) at serine(S)616. Another TLR4 agonist, lipopolysaccharide (LPS), also increased mitochondrial fission in a Drp1 and RhoA-ROCK-dependent manner. To validate our findings in vivo, we challenged C57BL/6 mice with eNAMPT in the presence and absence of the Drp1 inhibitor, Mdivi-1. Mdivi-1 treatment protected against eNAMPT-induced lung inflammation, edema, and lung injury. These studies demonstrate that mitochondrial fission-dependent disruption of mitochondrial function is essential in TLR4-mediated inflammatory lung injury and identify a key role for RhoA-ROCK signaling. Reducing mitochondrial fission could be a potential therapeutic strategy to improve ARDS outcomes.

The value of calcofluor white in the diagnosis of invasive fungal diseases

PURPOSE

To evaluate the value of calcofluor white in the diagnosis of invasive fungal disease (IFD).

METHODS

A total of 84 patients with possible pulmonary fungal infection who underwent bronchoscopy with bronchoalveolar lavage fluid (BALF) were included. All BALF specimens were subjected to Calcofluor white (CFW), potassium hydroxide (KOH) and Gram stains.

RESULTS

CFW has the most sensitivity than KOH and Gram staining. The specificity of CFW was 92.00 %, which was lower than that of Gram staining. The PPVs for CFW, KOH and Gram staining were 94.44 %, 84.62 % and 80.00 % respectively. The NPVs for CFW, KOH and Gram staining was 47.92 %, 32.39 % and 30.38 % respectively. The AUCs of these three methods were 0.748, 0.550 and 0.510 respectively.

CONCLUSION

CFW is superior to KOH and Gram staining in the diagnosis of invasive fungal diseases.

Amifostine ameliorates bleomycin-induced murine pulmonary fibrosis via NAD+/SIRT1/AMPK pathway-mediated effects on mitochondrial function and cellular metabolism

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a devastating chronic lung disease characterized by irreversible scarring of the lung parenchyma. Despite various interventions aimed at mitigating several different molecular aspects of the disease, only two drugs with limited clinical efficacy have so far been approved for IPF therapy.

OBJECTIVE

We investigated the therapeutic efficacy of amifostine, a detoxifying drug clinically used for radiation-caused cytotoxicity, in bleomycin-induced murine pulmonary fibrosis.

METHODS

C57BL6/J mice were intratracheally instilled with 3 U/kg of bleomycin. Three doses of amifostine (WR-2721, 200 mg/kg) were administered intraperitoneally on days 1, 3, and 5 after the bleomycin challenge. Bronchoalveolar lavage fluid (BALF) was collected on day 7 and day 21 for the assessment of lung inflammation, metabolites, and fibrotic injury. Human fibroblasts were treated in vitro with transforming growth factor beta 1 (TGF-β1), followed by amifostine (WR-1065, 1-4 µg/mL) treatment. The effects of TGF-β1 and amifostine on the mitochondrial production of reactive oxygen species (ROS) were assessed by live cell imaging of MitoSOX. Cellular metabolism was assessed by the extracellular acidification rate (ECAR), the oxygen consumption rate (OCR), and the concentrations of various energy-related metabolites as measured by mass spectrum (MS). Western blot analysis was performed to investigate the effect of amifostine on sirtuin 1 (SIRT1) and adenosine monophosphate activated kinase (AMPK).

RESULTS

Three doses of amifostine significantly attenuated lung inflammation and pulmonary fibrosis. Pretreatment and post-treatment of human fibroblast cells with amifostine blocked TGF-β1-induced mitochondrial ROS production and mitochondrial dysfunction in human fibroblast cells. Further, treatment of fibroblasts with TGF-β1 shifted energy metabolism away from mitochondrial oxidative phosphorylation (OXPHOS) and towards glycolysis, as observed by an altered metabolite profile including a decreased ratio of NAD + /NADH and increased lactate concentration. Treatment with amifostine significantly restored energy metabolism and activated SIRT1, which in turn activated AMPK. The activation of AMPK was required to mediate the effects of amifostine on mitochondrial homeostasis and pulmonary fibrosis. This study provides evidence that repurposing of the clinically used drug amifostine may have therapeutic applications for IPF treatment.

CONCLUSION

Amifostine inhibits bleomycin-induced pulmonary fibrosis by restoring mitochondrial function and cellular metabolism.

Sphingosine-1-Phosphate Receptor 3 Induces Endothelial Barrier Loss via ADAM10-Mediated Vascular Endothelial-Cadherin Cleavage

Mechanical ventilation (MV) is a life-supporting strategy employed in the Intensive Care Unit (ICU). However, MV-associated mechanical stress exacerbates existing lung inflammation in ICU patients, resulting in limited improvement in mortality and a condition known as Ventilator-Induced Lung Injury (VILI). Sphingosine-1-phosphate (S1P) is a circulating bioactive lipid that maintains endothelial integrity primarily through S1P receptor 1 (S1PR1). During VILI, mechanical stress upregulates endothelial S1PR3 levels. Unlike S1PR1, S1PR3 mediates endothelial barrier disruption through Rho-dependent pathways. However, the specific impact of elevated S1PR3 on lung endothelial function, apart from Rho activation, remains poorly understood. In this study, we investigated the effects of S1PR3 in endothelial pathobiology during VILI using an S1PR3 overexpression adenovirus. S1PR3 overexpression caused cytoskeleton rearrangement, formation of paracellular gaps, and a modified endothelial response towards S1P. It resulted in a shift from S1PR1-dependent barrier enhancement to S1PR3-dependent barrier disruption. Moreover, S1PR3 overexpression induced an ADAM10-dependent cleavage of Vascular Endothelial (VE)-cadherin, which hindered endothelial barrier recovery. S1PR3-induced cleavage of VE-cadherin was at least partially regulated by S1PR3-mediated NFκB activation. Additionally, we employed an S1PR3 inhibitor TY-52156 in a murine model of VILI. TY-52156 effectively attenuated VILI-induced increases in bronchoalveolar lavage cell counts and protein concentration, suppressed the release of pro-inflammatory cytokines, and inhibited lung inflammation as assessed via a histological evaluation. These findings confirm that mechanical stress associated with VILI increases S1PR3 levels, thereby altering the pulmonary endothelial response towards S1P and impairing barrier recovery. Inhibiting S1PR3 is validated as an effective therapeutic strategy for VILI.

SARS-CoV-2 neurotropism-induced anxiety and depression-like behaviors require Microglia activation

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been associated with a wide range of "long COVID" neurological symptoms. However, the mechanisms governing SARS-CoV-2 neurotropism and its effects on long-term behavioral changes remain poorly understood. Using a highly virulent mouse-adapted SARS-CoV-2 strain, denoted as SARS2-N501Y MA30 , we demonstrated that intranasal inoculation of SARS2-N501Y MA30 results in viral dissemination to multiple brain regions, including the amygdala and hippocampus. Behavioral assays show a significant increase in anxiety- and depression-like behaviors 14 days following viral infection. Moreover, we observed microglia activation following SARS2-N501Y MA30 infection, along with an augmentation in microglia-dependent neuronal activity in the amygdala. Pharmacological inhibition of microglial activity subsequent to viral spike inoculation mitigates microglia-dependent neuronal hyperactivity. Furthermore, transcriptomic analysis of infected brains revealed the upregulation of inflammatory and cytokine-related pathways, implicating microglia-driven neuroinflammation in the pathogenesis of neuronal hyperactivity and behavioral abnormality. Overall, these data provide critical insights into the neurological consequences of SARS-CoV-2 infection and underscore microglia as a potential therapeutic target for ameliorating virus-induced neurobehavioral abnormalities.

Metabolic reprogramming, oxidative stress, and pulmonary hypertension

Mitochondria are highly dynamic organelles essential for cell metabolism, growth, and function. It is becoming increasingly clear that endothelial cell dysfunction significantly contributes to the pathogenesis and vascular remodeling of various lung diseases, including pulmonary arterial hypertension (PAH), and that mitochondria are at the center of this dysfunction. The more we uncover the role mitochondria play in pulmonary vascular disease, the more apparent it becomes that multiple pathways are involved. To achieve effective treatments, we must understand how these pathways are dysregulated to be able to intervene therapeutically. We know that nitric oxide signaling, glucose metabolism, fatty acid oxidation, and the TCA cycle are abnormal in PAH, along with alterations in the mitochondrial membrane potential, proliferation, and apoptosis. However, these pathways are incompletely characterized in PAH, especially in endothelial cells, highlighting the urgent need for further research. This review summarizes what is currently known about how mitochondrial metabolism facilitates a metabolic shift in endothelial cells that induces vascular remodeling during PAH.

[Research progress of FAPI PET/CT in the diagnosis of malignant liver tumors]

Malignant liver tumors have a high incidence and mortality rate. Therefore, it is of great significance to promptly learn about tumor advancement status through relevant examinations for patients' follow-up, diagnosis, and therapy as well as the improvement of the five-year survival rate. The primary lesions and intrahepatic metastases of malignant liver tumors have been better demonstrated in the clinical study with the use of various isotope-labeled fibroblast activating protein inhibitors because of their low uptake in liver tissues and high tumor/background ratio, which provides a new method for early diagnosis, precise staging, and radionuclide therapy. In light of this context, a review of the research progress of fibroblast-activating protein inhibitors for the diagnosis of liver malignant tumors is presented.

[Chinese expert consensus on management of dyslipidemia in the elderly]

Dyslipidemia is an important risk factor of atherosclerotic cardiovascular disease (ASCVD). Statins delay the occurrence and development of ASCVD, and reduce the risk of cardiovascular events and death. Due to safety concerns, there exist insufficient use of lipid-lowering agents and a high withdrawal rate of the agents in the elderly. To promote the prevention and treatment of ASCVD, this expert consensus is issued and focuses on the management of dyslipidemia of Chinese elderly basing on the clinical evidence of the use of lipid-lowering drugs by the elderly, and the lipid management guidelines and expert consensus recommendations at home and abroad.

NOX4 Mediates Epithelial Cell Death in Hyperoxic Acute Lung Injury Through Mitochondrial Reactive Oxygen Species

Management of acute respiratory distress involves O₂ supplementation, which is lifesaving, but causes severe hyperoxic acute lung injury (HALI). NADPH oxidase (NOX) could be a major source of reactive oxygen species (ROS) in hyperoxia (HO). Epithelial cell death is a crucial step in the development of many lung diseases. Alveolar type II (AT2) cells are the metabolically active epithelial cells of alveoli that serve as a source of AT1 cells following lung injury. The aim of this study was to determine the possible role of AT2 epithelial cell NOX4 in epithelial cell death from HALI. Wild type (WT), Nox4^fl/fl (control), and Nox4^−/−Spc-Cre mice were exposed to room air (NO) or 95% O₂ (HO) to investigate the structural and functional changes in the lung. C57BL/6J WT animals subjected to HO showed increased expression of lung NOX4 compared to NO. Significant HALI, increased bronchoalveolar lavage cell counts, increased protein levels, elevated proinflammatory cytokines and increased AT2 cell death seen in hyperoxic Nox4^fl/fl control mice were attenuated in HO-exposed Nox4^−/−Spc-Cre mice. HO-induced expression of NOX4 in MLE cells resulted in increased mitochondrial (mt) superoxide production and cell apoptosis, which was reduced in NOX4 siRNA silenced cells. This study demonstrates a novel role for epithelial cell NOX4 in accelerating lung epithelial cell apoptosis from HALI. Deletion of the Nox4 gene in AT2 cells or silencing NOX4 in lung epithelial cells protected the lungs from severe HALI with reduced apoptosis and decreased mt ROS production in HO. These results suggest NOX4 as a potential target for the treatment of HALI.

Omega-3 polyunsaturated fatty acids alleviate adenine-induced chronic renal failure via regulating ROS production and TGF-β/SMAD pathway

The article "Omega-3 polyunsaturated fatty acids alleviate adenine-induced chronic renal failure via regulating ROS production and TGF-β/SMAD pathway", by J. Xu, Z.-P. Feng, H.-Y. Peng, P. Fu, published in Eur Rev Med Pharmacol Sci 2018; 22 (15): 5024-5032-DOI: 10.26355/eurrev_201808_15645-PMID: 30070341, has been retracted by the authors due to input errors which occurred in the experimental data. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/15645.

Do nicotine dependence influencing and non-influencing behaviors have an association with high nicotine dependence in smokers?

INTRODUCTION

Nicotine dependence (ND) is a maladaptive pattern of tobacco smoking with withdrawal symptoms similar to other drug addictive disorders. It is very common in clinical practice that smokers always have different degrees of nicotine dependence with the same amount of tobacco consumption. Behaviors may influence daily cigarette consumption or smoking status. Hence it is critical to ascertain the association between concurrent behaviors and high nicotine dependence among smokers.

METHODS

A total of 343 patients who attended a clinic for smoking cessation were recruited, and the information on concurrent behaviors were recorded. Factors associated and not associated with nicotine dependence were recorded. Nicotine dependence was determined by Fagerström test for nicotine dependence (FTND).

RESULTS

High ND patients (FTND >5) showed significant behaviors distribution compared with mild and moderate ND patients (FTND ≤5). There is no single behavior that was significantly different between high ND and mild and moderate ND smokers. However, the combined effects of nicotine dependence influencing behaviors of caffeine drinking and mental activities after dinner have an association with high ND (OR=1.939; 95% CI: 1.154–3.258, p=0.012). In addition, the combined effects of inadequate sleep time (<8 hours), caffeine drinking and mental activities after dinner significantly distinguished patients of high ND from those of low ND (OR=2.208; 95% CI: 1.032–4.737, p=0.042).

CONCLUSIONS

Interaction effects of mental activities after dinner and caffeine drinking have an association with high nicotine dependence. Sleep of less than 8 hours with behaviors of mental activities after dinner and caffeine drinking have the same effect.

Essential role for paxillin tyrosine phosphorylation in LPS-induced mitochondrial fission, ROS generation and lung endothelial barrier loss

We have shown that both reactive oxygen species (ROS) and paxillin tyrosine phosphorylation regulate LPS-induced human lung endothelial permeability. Mitochondrial ROS (mtROS) is known to increase endothelial cell (EC) permeability which requires dynamic change in mitochondrial morphology, events that are likely to be regulated by paxillin. Here, we investigated the role of paxillin and its tyrosine phosphorylation in regulating LPS-induced mitochondrial dynamics, mtROS production and human lung microvascular EC (HLMVEC) dysfunction. LPS, in a time-dependent manner, induced higher levels of ROS generation in the mitochondria compared to cytoplasm or nucleus. Down-regulation of paxillin expression with siRNA or ecto-expression of paxillin Y31F or Y118F mutant plasmids attenuated LPS-induced mtROS in HLMVECs. Pre-treatment with MitoTEMPO, a scavenger of mtROS, attenuated LPS-induced mtROS, endothelial permeability and VE-cadherin phosphorylation. Further, LPS-induced mitochondrial fission in HLMVECs was attenuated by both a paxillin siRNA, and paxillin Y31F/Y118F mutant. LPS stimulated phosphorylation of dynamin-related protein (DRP1) at S616, which was also attenuated by paxillin siRNA, and paxillinY31/Y118 mutants. Inhibition of DRP1 phosphorylation by P110 attenuated LPS-induced mtROS and endothelial permeability. LPS challenge of HLMVECs enhanced interaction between paxillin, ERK, and DRP1, and inhibition of ERK1/2 activation with PD98059 blocked mitochondrial fission. Taken together, these results suggest a key role for paxillin tyrosine phosphorylation in LPS-induced mitochondrial fission, mtROS generation and EC barrier dysfunction.

Hyperoxia-induced S1P1 signaling reduced angiogenesis by suppression of TIE-2 leading to experimental bronchopulmonary dysplasia

INTRODUCTION

We have earlier shown that hyperoxia (HO)-induced sphingosine kinase 1 (SPHK1)/sphingosine-1-phosphate (S1P) signaling contribute to bronchopulmonary dysplasia (BPD). S1P acts through G protein-coupled receptors, S1P₁ through S1P₅. Further, we noted that heterozygous deletion of S1pr1 ameliorated the HO-induced BPD in the murine model. The mechanism by which S1P₁ signaling contributes to HO-induced BPD was explored.

METHODS

S1pr1^+/+ and S1pr1^+/- mice pups were exposed to either room air (RA) or HO (75% oxygen) for 7 days from PN 1-7. Lung injury and alveolar simplification was evaluated. Lung protein expression was determined by Western blotting and immunohistochemistry (IHC). In vitro experiments were performed using human lung microvascular endothelial cells (HLMVECs) with S1P₁ inhibitor, NIBR0213 to interrogate the S1P₁ signaling pathway.

RESULTS

HO increased the expression of S1pr1 gene as well as S1P₁ protein in both neonatal lungs and HLMVECs. The S1pr1^+/- neonatal mice showed significant protection against HO-induced BPD which was accompanied by reduced inflammation markers in the bronchoalveolar lavage fluid. HO-induced reduction in ANG-1, TIE-2, and VEGF was rescued in S1pr1^+/- mouse, accompanied by an improvement in the number of arterioles in the lung. HLMVECs exposed to HO increased the expression of KLF-2 accompanied by reduced expression of TIE-2, which was reversed with S1P₁ inhibition.

CONCLUSION

HO induces S1P₁ followed by reduced expression of angiogenic factors. Reduction of S1P₁ signaling restores ANG-1/ TIE-2 signaling leading to improved angiogenesis and alveolarization thus protecting against HO-induced neonatal lung injury.

Nuclear Sphingosine-1-phosphate Lyase Generated ∆2-hexadecenal is A Regulator of HDAC Activity and Chromatin Remodeling in Lung Epithelial Cells

Sphingosine-1-phosphate (S1P), a bioactive lipid mediator, is generated from sphingosine by sphingosine kinases (SPHKs) 1 and 2 and is metabolized to ∆2-hexadecenal (∆2-HDE) and ethanolamine phosphate by S1P lyase (S1PL) in mammalian cells. We have recently demonstrated the activation of nuclear SPHK2 and the generation of S1P in the nucleus of lung epithelial cells exposed to Pseudomonas aeruginosa. Here, we have investigated the nuclear localization of S1PL and the role of ∆2-HDE generated from S1P in the nucleus as a modulator of histone deacetylase (HDAC) activity and histone acetylation. Electron micrographs of the nuclear fractions isolated from MLE-12 cells showed nuclei free of ER contamination, and S1PL activity was detected in nuclear fractions isolated from primary lung bronchial epithelial cells and alveolar epithelial MLE-12 cells. Pseudomonas aeruginosa-mediated nuclear ∆2-HDE generation, and H3/H4 histone acetylation was attenuated by S1PL inhibitors in MLE-12 cells and human bronchial epithelial cells. In vitro, the addition of exogenous ∆2-HDE (100-10,000 nM) to lung epithelial cell nuclear preparations inhibited HDAC1/2 activity, and increased acetylation of Histone H3 and H4, whereas similar concentrations of S1P did not show a significant change. In addition, incubation of ∆2-HDE with rHDAC1 generated five different amino acid adducts as detected by LC-MS/MS; the predominant adduct being ∆2-HDE with lysine residues of HDAC1. Together, these data show an important role for the nuclear S1PL-derived ∆2-HDE in the modification of HDAC activity, histone acetylation, and chromatin remodeling in lung epithelial cells.

Absent Cortical Venous Filling Is Associated with Aggravated Brain Edema in Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Predicting malignant cerebral edema can help identify patients who may benefit from appropriate evidence-based interventions. We investigated whether absent cortical venous filling is associated with more pronounced early brain edema, which leads to malignant cerebral edema.

MATERIALS AND METHODS

Patients with acute ischemic stroke caused by large-vessel occlusion in the MCA territory who presented between July 2017 and September 2019 to our hospital were included. Collateral filling was rated using the modified Tan scale on CTA, and good collaterals were defined as a score of 2-3. The Cortical Vein Opacification Score (COVES) was calculated, and absent cortical venous filling was defined as a score of 0. Early brain edema was determined using net water uptake on baseline CT images. Malignant cerebral edema was defined as a midline shift of ≥5 mm on follow-up imaging or a massive cerebral swelling leading to decompressive hemicraniectomy or death. Multivariate linear and logistic regression models were performed to analyze data.

RESULTS

A total of 163 patients were included. Net water uptake was significantly higher in patients with absent than in those with favorable cortical venous filling (8.1% versus 4.2%; P < .001). In the multivariable regression analysis, absent cortical venous filling (β = 2.04; 95% CI, 0.75-3.32; P = .002) was significantly and independently associated with higher net water uptake. Absent cortical venous filling (OR, 14.68; 95% CI, 4.03-53.45; P < .001) and higher net water uptake (OR, 1.29; 95% CI, 1.05-1.58; P = .016) were significantly associated with increased likelihood of malignant cerebral edema.

CONCLUSIONS

Patients with absent cortical venous filling were associated with an increased early brain edema and a higher risk of malignant cerebral edema. These patients may be targeted for optimized adjuvant antiedematous treatment.

NOX4 Mediates Pseudomonas aeruginosa-Induced Nuclear Reactive Oxygen Species Generation and Chromatin Remodeling in Lung Epithelium

Pseudomonas aeruginosa (PA) infection increases reactive oxygen species (ROS), and earlier, we have shown a role for NADPH oxidase-derived ROS in PA-mediated lung inflammation and injury. Here, we show a role for the lung epithelial cell (LEpC) NOX4 in PA-mediated chromatin remodeling and lung inflammation. Intratracheal administration of PA to Nox4flox/flox mice for 24 h caused lung inflammatory injury; however, epithelial cell-deleted Nox4 mice exhibited reduced lung inflammatory injury, oxidative stress, secretion of pro-inflammatory cytokines, and decreased histone acetylation. In LEpCs, NOX4 was localized both in the cytoplasmic and nuclear fractions, and PA stimulation increased the nuclear NOX4 expression and ROS production. Downregulation or inhibition of NOX4 and PKC δ attenuated the PA-induced nuclear ROS. PA-induced histone acetylation was attenuated by Nox4-specific siRNA, unlike Nox2. PA stimulation increased HDAC1/2 oxidation and reduced HDAC1/2 activity. The PA-induced oxidation of HDAC2 was attenuated by N-acetyl-L-cysteine and siRNA specific for Pkc δ, Sphk2, and Nox4. PA stimulated RAC1 activation in the nucleus and enhanced the association between HDAC2 and RAC1, p-PKC δ, and NOX4 in LEpCs. Our results revealed a critical role for the alveolar epithelial NOX4 in mediating PA-induced lung inflammatory injury via nuclear ROS generation, HDAC1/2 oxidation, and chromatin remodeling.

The effect of a consortium of Penicillium sp. and Bacillus spp. in suppressing banana fungal diseases caused by Fusarium sp. and Alternaria sp

AIMS

This study sought to utilize indigenous soil micro-organisms to suppress wilt-causing fungal pathogens of the banana.

METHODS AND RESULTS

Fungal pathogens were isolated from wilt-affected rhizospheric soil, and potential antagonistic bacterial strains were isolated from healthy rhizospheric soil in the same area from which fungal pathogens were isolated. The antifungal activity of isolated micro-organisms against fungal pathogens was studied both in vitro and in vivo against fungal pathogens. It was found that Fusarium oxysporum and Alternaria sp. were pathogenic, while Penicillium sp., Bacillus velezensis and Bacillus subtilis were antagonistic. Moreover, it was seen that B. velezensis, B. subtilis and Penicillium sp. inhibited the growth of the two fungal pathogens in both in vitro and in vivo experiments. Further investigation indicated that B. velezensis, B. subtilis and Penicillium sp. were able to produce enzymatic antifungal compounds (chitinase and β-1,3-glucanase). The spray application around rhizome revealed that a combination of Bacillus spp. and Penicillium sp. in greenhouse conditions gave the highest reduction in disease severity by up to 60% to both fungal pathogens among the treatments.

CONCLUSIONS

Banana disease is seen to be induced not only by F. oxysporum but also by Alternaria sp. The isolated indigenous micro-organisms can effectively control both the pathogens. The combination of isolated antagonistic micro-organisms has thus demonstrated substantial potential for suppressing banana disease.

SIGNIFICANCE AND IMPACT OF THE STUDY

An antagonistic consortium isolated in this study has demonstrated remarkable potential for controlling fungal diseases caused by Fusarium sp. and Alternaria sp. Therefore, the use of indigenous microflora to improve disease suppression of banana plants against soil-borne pathogens is a preferable approach.

Mitochondria: Potential Targets for Osteoarthritis

Osteoarthritis (OA) is a common and disabling joint disorder that is mainly characterized by cartilage degeneration and narrow joint spaces. The role of mitochondrial dysfunction in promoting the development of OA has gained much attention. Targeting endogenous molecules to improve mitochondrial function is a potential treatment for OA. Moreover, research on exogenous drugs to improve mitochondrial function in OA based on endogenous molecular targets has been accomplished. In addition, stem cells and exosomes have been deeply researched in the context of cartilage regeneration, and these factors both reverse mitochondrial dysfunctions. Thus, we hypothesize that biomedical approaches will be applied to the treatment of OA. Furthermore, we have summarized the global status of mitochondria and osteoarthritis research in the past two decades, which will contribute to the research field and the development of novel treatment strategies for OA.

Neonatal therapy with PF543, a sphingosine kinase 1 inhibitor, ameliorates hyperoxia-induced airway remodeling in a murine model of bronchopulmonary dysplasia

Hyperoxia (HO)-induced lung injury contributes to bronchopulmonary dysplasia (BPD) in preterm newborns. Intractable wheezing seen in BPD survivors is associated with airway remodeling (AWRM). Sphingosine kinase 1 (SPHK1)/sphingosine-1-phosphate (S1P) signaling promotes HO-mediated neonatal BPD; however, its role in the sequela of AWRM is not known. We noted an increased concentration of S1P in tracheal aspirates of neonatal infants with severe BPD, and earlier, demonstrated that Sphk1^-/- mice showed protection against HO-induced BPD. The role of SPHK1/S1P in promoting AWRM following exposure of neonates to HO was investigated in a murine model. Therapy using PF543, the specific SPHK1 inhibitor, during neonatal HO reduced alveolar simplification followed by reduced AWRM in adult mice. This was associated with reduced airway hyperreactivity to intravenous methacholine. Neonatal HO exposure was associated with increased expression of SPHK1 in lung tissue of adult mice, which was reduced with PF543 therapy in the neonatal stage. This was accompanied by amelioration of HO-induced reduction of E-cadherin in airway epithelium. This may be suggestive of arrested partial epithelial mesenchymal transition (EMT) induced by HO. In vitro studies using human primary airway epithelial cells (HAEpCs) showed that SPHK1 inhibition or deletion restored HO-induced reduction in E-cadherin and reduced formation of mitochondrial reactive oxygen species (mtROS). Blocking mtROS with MitoTempo attenuated HO-induced partial EMT of HAEpCs. These results collectively support a therapeutic role for PF543 in preventing HO-induced BPD in neonates and the long-term sequela of AWRM, thus conferring a long-term protection resulting in improved lung development and function.

Advancements in understanding the role of lysophospholipids and their receptors in lung disorders including bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is a devastating chronic neonatal lung disease leading to serious adverse consequences. Nearly 15 million babies are born preterm accounting for >1 in 10 births globally. The aetiology of BPD is multifactorial and the survivors suffer lifelong respiratory morbidity. Lysophospholipids (LPL), which include sphingosine-1-phosphate (S1P), and lysophosphatidic acid (LPA) are both naturally occurring bioactive lipids involved in a variety of physiological and pathological processes such as cell survival, death, proliferation, migration, immune responses and vascular development. Altered LPL levels have been observed in a number of lung diseases including BPD, which underscores the importance of these signalling lipids under normal and pathophysiological situations. Due to the paucity of information related to LPLs in BPD, most of the ideas related to BPD and LPL are speculative. This article is intended to promote discussion and generate hypotheses, in addition to the limited review of information related to BPD already established in the literature.

Angiocrine Sphingosine-1-Phosphate Activation of S1PR2-YAP Signaling Axis in Alveolar Type II Cells Is Essential for Lung Repair

Lung alveolar epithelium is composed of alveolar type I (AT1) and type II (AT2) cells. AT1 cells mediate gas exchange, whereas AT2 cells act as progenitor cells to repair injured alveoli. Lung microvascular endothelial cells (LMVECs) play a crucial but still poorly understood role in regulating alveolar repair. Here, we studied the role of the LMVEC-derived bioactive lipid sphingosine-1-phosphate (S1P) in promoting alveolar repair using mice with endothelial-specific deletion of sphingosine kinase 1 (Sphk1), the key enzyme promoting S1P generation. These mutant lungs developed airspace-enlargement lesions and exhibited a reduced number of AT1 cells after Pseudomonas-aeruginosa-induced lung injury. We demonstrated that S1P released by LMVECs acted via its receptor, S1PR2, on AT2 cells and induced nuclear translocation of yes-associated protein (YAP), a regulator of AT2 to AT1 transition. Thus, angiocrine S1P released after injury acts via the S1PR2-YAP signaling axis on AT2 cells to promote AT2 to AT1 differentiation required for alveolar repair.

The status and trends of coronavirus research: A global bibliometric and visualized analysis

OBJECTIVES

The infectious pneumonia caused by the Coronavirus Disease 2019 (COVID-19) occurred in Wuhan, Hubei Province, China, from December 2019 and spread the whole country and even other 24 countries. Coronavirus research is of significance to overcome the epidemic. Our study aims to investigate the global status and trends of coronavirus research.

METHOD

Publications related to the studies of coronavirus research from January 1, 2003 to February 6, 2020 were retrieved from the Science Citation Index-Expanded (SCI-E) of the Web of Science database. A total of 9294 publications were included. The data source was studied and indexed by bibliometric methodology. For visualized study, bibliographic coupling analysis, co-authorship analysis, co-citation analysis, co-occurrence analysis and the analysis of publication trends in coronavirus research were conducted by VOS (visualization of similarities) viewer and GraphPadPrism 6 software.

RESULTS

The number of publications about coronavirus research increased sharply in 2004 for SARS outbreak and increased again in 2012 for MERS outbreak. The USA made the highest contributions to the global research with the most total number of publications, total citation frequency, and the highest H-index, while Netherlands had the highest average citation per item. Journal of Virology had the largest publication numbers. The University of Hong Kong is the most contributive institution with the most publications. The main research orientation and funding agency were virology and United States Department of Health Human Services. Keywords of all related studies could be divided into 4 clusters: "Pathological research," "Epidemiology research," "Clinical research," and "Mechanism research."

CONCLUSIONS

The outbreak of the epidemic could promote coronavirus research, meanwhile, coronavirus research contributes to overcoming the epidemic. Attention should be drawn to the latest popular research, including "Spike protein," "Receptor binding domain," and "Vaccine." Therefore, more and more efforts will be put into mechanism research and vaccine research and development, which can be helpful to deal with the epidemic.

Phospholipase D2 restores endothelial barrier function by promoting PTPN14-mediated VE-cadherin dephosphorylation

Increased permeability of vascular lung tissues is a hallmark of acute lung injury and is often caused by edemagenic insults resulting in inflammation. Vascular endothelial (VE)-cadherin undergoes internalization in response to inflammatory stimuli and is recycled at cell adhesion junctions during endothelial barrier re-establishment. Here, we hypothesized that phospholipase D (PLD)-generated phosphatidic acid (PA) signaling regulates VE-cadherin recycling and promotes endothelial barrier recovery by dephosphorylating VE-cadherin. Genetic deletion of PLD2 impaired recovery from protease-activated receptor-1-activating peptide (PAR-1-AP)-induced lung vascular permeability and potentiated inflammation in vivo In human lung microvascular endothelial cells (HLMVECs), inhibition or deletion of PLD2, but not of PLD1, delayed endothelial barrier recovery after thrombin stimulation. Thrombin stimulation of HLMVECs increased co-localization of PLD2-generated PA and VE-cadherin at cell-cell adhesion junctions. Inhibition of PLD2 activity resulted in prolonged phosphorylation of Tyr-658 in VE-cadherin during the recovery phase 3 h post-thrombin challenge. Immunoprecipitation experiments revealed that after HLMVECs are thrombin stimulated, PLD2, VE-cadherin, and protein-tyrosine phosphatase nonreceptor type 14 (PTPN14), a PLD2-dependent protein-tyrosine phosphatase, strongly associate with each other. PTPN14 depletion delayed VE-cadherin dephosphorylation, reannealing of adherens junctions, and barrier function recovery. PLD2 inhibition attenuated PTPN14 activity and reversed PTPN14-dependent VE-cadherin dephosphorylation after thrombin stimulation. Our findings indicate that PLD2 promotes PTPN14-mediated dephosphorylation of VE-cadherin and that redistribution of VE-cadherin at adherens junctions is essential for recovery of endothelial barrier function after an edemagenic insult.

S1P and plasmalogen derived fatty aldehydes in cellular signaling and functions

Long-chain fatty aldehydes are present in low concentrations in mammalian cells and serve as intermediates in the interconversion between fatty acids and fatty alcohols. The long-chain fatty aldehydes are generated by enzymatic hydrolysis of 1-alkyl-, and 1-alkenyl-glycerophospholipids by alkylglycerol monooxygenase, plasmalogenase or lysoplasmalogenase while hydrolysis of sphingosine-1-phosphate (S1P) by S1P lyase generates trans ∆2-hexadecenal (∆2-HDE). Additionally, 2-chloro-, and 2-bromo- fatty aldehydes are produced from plasmalogens or lysoplasmalogens by hypochlorous, and hypobromous acid generated by activated neutrophils and eosinophils, respectively while 2-iodofatty aldehydes are produced by excess iodine in thyroid glands. The 2-halofatty aldehydes and ∆2-HDE activated JNK signaling, BAX, cytoskeletal reorganization and apoptosis in mammalian cells. Further, 2-chloro- and 2-bromo-fatty aldehydes formed GSH and protein adducts while ∆2-HDE formed adducts with GSH, deoxyguanosine in DNA and proteins such as HDAC1 in vitro. ∆2-HDE also modulated HDAC activity and stimulated H3 and H4 histone acetylation in vitro with lung epithelial cell nuclear preparations. The α-halo fatty aldehydes elicited endothelial dysfunction, cellular toxicity and tissue damage. Taken together, these investigations suggest a new role for long-chain fatty aldehydes as signaling lipids, ability to form adducts with GSH, proteins such as HDACs and regulate cellular functions.

Three-Stage Masquelet Technique and One-Stage Reconstruction to Treat Foot and Ankle Tuberculosis

BACKGROUND

The purpose of this article was to report the feasibility and effectiveness of 3-stage Masquelet technique and 1-stage operation for different stages of foot and ankle tuberculosis (TB).

METHODS

Ten consecutive patients with foot and ankle TB were retrospectively analyzed between January 2014 and December 2018. Five patients were treated with the 3-stage Masquelet technique, including thorough debridement with vacuum sealing drainage, implantation of antibiotic cement spacer, and subsequent reconstruction. Five patients were treated with a 1-stage reconstruction. The American Orthopaedic Foot & Ankle Society (AOFAS) and visual analog scale (VAS) pain scores were recorded at the last follow-up. The follow-up was 30.3 ± 17.8 months.

RESULTS

No reactivation of TB was observed in any patients. For the 3-stage operation group, 1 patient developed a distal tibia fracture. The duration of anti-TB therapy was 12.0 ± 0.8 months. The AOFAS score increased from 39.5 ± 9.9 preoperatively to 75.3 ± 7.0 postoperatively (P < .05). The VAS pain score decreased from 6.3 ± 1.9 to 1.5 ± 1.3 (P < .05). For the 1-stage operation, 1 patient had wound necrosis. The duration of anti-TB therapy was 13.8 ± 1.1 months. The AOFAS score increased from 51.8 ± 15.0 to 81.8 ± 6.3 (P < .05). The VAS pain score decreased from 5.4 ± 1.1 to 1.0 ± 0.7 (P < .05).

CONCLUSION

Three-stage operation was effective for foot and ankle TB with stage IV, sinus tracts or other infections, and 1-stage reconstruction was effective for early-stage TBs.

LEVEL OF EVIDENCE

Level IV, case series.

Genetic deletion of Sphk2 confers protection against Pseudomonas aeruginosa mediated differential expression of genes related to virulent infection and inflammation in mouse lung

BACKGROUND

Pseudomonas aeruginosa (PA) is an opportunistic Gram-negative bacterium that causes serious life threatening and nosocomial infections including pneumonia. PA has the ability to alter host genome to facilitate its invasion, thus increasing the virulence of the organism. Sphingosine-1- phosphate (S1P), a bioactive lipid, is known to play a key role in facilitating infection. Sphingosine kinases (SPHK) 1&2 phosphorylate sphingosine to generate S1P in mammalian cells. We reported earlier that Sphk2-/- mice offered significant protection against lung inflammation, compared to wild type (WT) animals. Therefore, we profiled the differential expression of genes between the protected group of Sphk2-/- and the wild type controls to better understand the underlying protective mechanisms related to the Sphk2 deletion in lung inflammatory injury. Whole transcriptome shotgun sequencing (RNA-Seq) was performed on mouse lung tissue using NextSeq 500 sequencing system.

RESULTS

Two-way analysis of variance (ANOVA) analysis was performed and differentially expressed genes following PA infection were identified using whole transcriptome of Sphk2-/- mice and their WT counterparts. Pathway (PW) enrichment analyses of the RNA seq data identified several signaling pathways that are likely to play a crucial role in pneumonia caused by PA such as those involved in: 1. Immune response to PA infection and NF-κB signal transduction; 2. PKC signal transduction; 3. Impact on epigenetic regulation; 4. Epithelial sodium channel pathway; 5. Mucin expression; and 6. Bacterial infection related pathways. Our genomic data suggests a potential role for SPHK2 in PA-induced pneumonia through elevated expression of inflammatory genes in lung tissue. Further, validation by RT-PCR on 10 differentially expressed genes showed 100% concordance in terms of vectoral changes as well as significant fold change.

CONCLUSION

Using Sphk2-/- mice and differential gene expression analysis, we have shown here that S1P/SPHK2 signaling could play a key role in promoting PA pneumonia. The identified genes promote inflammation and suppress others that naturally inhibit inflammation and host defense. Thus, targeting SPHK2/S1P signaling in PA-induced lung inflammation could serve as a potential therapy to combat PA-induced pneumonia.

Omega-3 polyunsaturated fatty acids alleviate adenine-induced chronic renal failure via regulating ROS production and TGF-β/SMAD pathway

OBJECTIVE

To explore the role of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) in adenine-induced rat chronic renal failure and its underlying mechanism.

MATERIALS AND METHODS

30 Sprague Dawley (SD) rats were randomly assigned into three groups, namely sham group, adenine induction group (adenine group) and adenine induction + ω-3 PUFAs treatment group (ω-3 PUFAs group), with 10 rats in each group. Serum and kidney samples were collected after rats were sacrificed. Serum levels of Cr (creatinine) and BUN (urea nitrogen) were detected using commercial kits. HE (hematoxylin and eosin) staining was performed to evaluate the pathological changes of kidneys. Levels of oxidative stress indicators in rat kidney homogenate were detected by relative commercial kits, including SOD (superoxide dismutase), GSH (reduced glutathione), CAT (catalase), and T-AOC (total antioxidant capacity). Reactive oxygen species (ROS) production was also detected by immunofluorescence. Protein expressions of nuclear factor E2 related factor 2 (Nrf2) and transforming growth factor-beta (TGF-β)/SMAD pathway-related genes were detected by Western blot.

RESULTS

Serum levels of Cr and BUN in ω-3 PUFAs group were remarkably decreased compared with those of adenine group. Higher contents of SOD, GSH, CAT and T-AOC were observed in ω-3 PUFAs group compared with those of adenine group. Besides, MAD content and ROS production were lower in ω-3 PUFAs group than those of adenine group. Pathological changes of kidneys were alleviated after ω-3 PUFAs treatment. Western blot results demonstrated that ω-3 PUFAs treatment remarkably upregulates Nrf2, HO-1, NQO1, but downregulates relative genes in TGF-β/SMAD pathway.

CONCLUSIONS

ω-3 PUFAs alleviated adenine-induced chronic renal failure through enhancing antioxidant stress and inhibiting inflammatory response via regulating Nrf2 and TGF-β/SMAD pathway.

Pseudomonas aeruginosa stimulates nuclear sphingosine-1-phosphate generation and epigenetic regulation of lung inflammatory injury

INTRODUCTION

Dysregulated sphingolipid metabolism has been implicated in the pathogenesis of various pulmonary disorders. Nuclear sphingosine-1-phosphate (S1P) has been shown to regulate histone acetylation, and therefore could mediate pro-inflammatory genes expression.

METHODS

Profile of sphingolipid species in bronchoalveolar lavage fluids and lung tissue of mice challenged with Pseudomonas aeruginosa (PA) was investigated. The role of nuclear sphingosine kinase (SPHK)2 and S1P in lung inflammatory injury by PA using genetically engineered mice was determined.

RESULTS

Genetic deletion of Sphk2, but not Sphk1, in mice conferred protection from PA-mediated lung inflammation. PA infection stimulated phosphorylation of SPHK2 and its localisation in epithelial cell nucleus, which was mediated by protein kinase C (PKC) δ. Inhibition of PKC δ or SPHK2 activity reduced PA-mediated acetylation of histone H3 and H4, which was necessary for the secretion of pro-inflammatory cytokines, interleukin-6 and tumour necrosis factor-α. The clinical significance of the findings is supported by enhanced nuclear localisation of p-SPHK2 in the epithelium of lung specimens from patients with cystic fibrosis (CF).

CONCLUSIONS

Our studies define a critical role for nuclear SPHK2/S1P signalling in epigenetic regulation of bacterial-mediated inflammatory lung injury. Targeting SPHK2 may represent a potential strategy to reduce lung inflammatory pulmonary disorders such as pneumonia and CF.

Role of phospholipase D in bleomycin-induced mitochondrial reactive oxygen species generation, mitochondrial DNA damage, and pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a pernicious lung disease characterized by alveolar epithelial apoptosis, dysregulated repair of epithelial injury, scar formation, and respiratory failure. In this study, we identified phospholipase D (PLD)-generated phosphatidic acid (PA) signaling in the development of pulmonary fibrosis (PF). Of the PLD isoenzymes, the protein expression of PLD2, but not PLD1, was upregulated in lung tissues from IPF patients and bleomycin challenged mice. Both PLD1 (Pld1^-/-)- and PLD2 (Pld2^-/-)-deficient mice were protected against bleomycin-induced lung inflammation and fibrosis, thereby establishing the role of PLD in fibrogenesis. The role of PLD1 and PLD2 in bleomycin-induced lung epithelial injury was investigated by infecting bronchial airway epithelial cells (Beas2B) with catalytically inactive mutants of PLD (hPLD1-K898R or mPld2-K758R) or downregulation of expression of PLD1 or PLD2 with siRNA. Bleomycin stimulated mitochondrial (mt) superoxide production, mtDNA damage, and apoptosis in Beas2B cells, which was attenuated by the catalytically inactive mutants of PLD or PLD2 siRNA. These results show a role for PLD1 and PLD2 in bleomycin-induced generation of mt reactive oxygen species, mt DNA damage, and apoptosis of lung epithelial cells in mice. Thus, PLD may be a novel therapeutic target in ameliorating experimental PF in mice.

Abstract P4-14-14: Clinicopathological features and endocrine therapy mode of ER low expression (1%-9%) breast cancer patients in China

Purpose: Since 2010, ASCO/CAP recommended that ER be considered positive if ≥1% tumor cells with positive nuclear staining by immunohistochemistry (IHC) in breast cancer. ASCO/CAP also recommended considering endocrine therapy (ET) in ER positive patients. However, most breast cancers are either ER negative or ER strongly positive (≥10%), and tumors with low ER (1-9%) expression are rare. Up to now, the effect of ET is controversial for these patients with ER 1-9% and unfortunately, we know little about the clinical information of this subgroup. In this study, we analyzed the clinicopathological characteristics and ET mode of patients with low ER expression. We sought to figure out whether the ASCO/CAP guidelines affect clinical ET decision in China and Which features are important considerations for doctors to choose ET. We also evaluated the efficacy of ET in these patients. Methods: Patients diagnosed stage I-III primary invasive breast cancer with ER low expression (1-9%) between January 2008 and December 2016 were retrospectively identified from six hospitals in China. Result: 457 patients (2.7%) had low expression of ER (1-9%) of 17216 patients. Mean age at diagnosis was 49 years. 288 patients (49.9%)were younger than 50 years old. 254 patients (55.6%) had stage II disease and 37 patients (8.1%) had lymphovascular invasion (LVI). 260 patients (56.9%) were HER2 positive; 408 patients had PR negative or low expression; 327 patients' (71.6%) Ki-67 status were &gt; 20%. 388 patients (85%) received chemotherapy. Of those 388 patients, 90% patients received anthracycline combined with taxol chemotherapy regimens. 170 patients (37.2%)received ET. Before 2010, only 25.7% patients with low ER expression received ET. The proportion of ET increased after the 2010 ASCO/CAP guideline was published. In 2013, 50% patients received ET. The rate of ET was totally different in six hospitals. 55% patients received ET in the hospital with highest rate, while only 4% patients received ET in the hospital with lowest rate. Using the univariate logistic regression analysis of ET, ER expression, PR expression, Ki-67 status and LVI were associated with the rate of ET. But after adjustment for other covariates, only ER level was significantly associated with the rate of ET. Compared to patients with ER&lt;5% tumors, patients with ER≥5% tumors had a significantly higher probability of ET rate (OR, 2.882; 95% CI: 1.928-4.308; P &lt; 0.001). Median follow time was 30 months. The 5-year RFS rate was 85%. Younger age and positive lymph nodes were associated with worse RFS. Survival rate did not differ significantly between patients with or without ET (without ER vs with ET: OR, 0.870; 95% CI: 0.508-1.448; p=0.61). Conclusions: 2010 ACSO/CAP recommendation indeed result in an increase of ET rate for patients with 1%-9% ER positive. But these patients do not appear to benefit from ET. Prospective studies are needed for these patients and we need more accurate way to evaluate ER levels, which associate with endocrine response.

Citation Format: Fu P, Wang S, Yao M, Xiang A, Li J, Wang H, Geng C, Jin F, Yin Y, Huang X, Jiang Z. Clinicopathological features and endocrine therapy mode of ER low expression (1%-9%) breast cancer patients in China [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-14-14.