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1.
JCI Insight ; 6(12)2021 06 22.
Article in English | MEDLINE | ID: mdl-34156033

ABSTRACT

Necroptosis has emerged as a potential mechanism in the pathogenesis of chronic obstructive pulmonary disease (COPD). Here, we found that markers of necroptosis, including high mobility group box 1 release and phosphorylation of mixed lineage kinase domain-like protein (p-MLKL), were markedly induced in the late stage of cigarette smoking-induced (CS-induced) emphysema in mouse lung tissue as well as in lung epithelial cells and organoids with higher dosage of or more prolonged exposure to cigarette smoking extract (CSE). Apoptotic signals were also detected and maximally induced in the early stage of CS-exposed mice and CSE-treated epithelial cells. Inhibition of apoptosis by Z-VAD, a pan-caspase inhibitor, switched the cellular stress to enhanced necroptosis in lung epithelial cells and organoids treated with CSE. Depletion or inhibition of receptor-interacting protein kinase 3 (RIP3) or MLKL attenuated the CSE-induced cell death, suggesting that necroptosis contributes to CSE-induced cell death. Silencing or inhibition of RIP1 had no protective effect, indicating a RIP1-independent RIP3 activation pathway. CSE-induced necroptosis released more damage-associated molecular patterns and evoked greater engulfment but slower clearance by bone marrow-derived macrophages, leading to enhanced expression of proinflammatory cytokines Tnfα and Il6. Finally, our in vivo data verified that inhibition of necroptosis by RIP3 inhibitor GSK'872 protected mice from CS-induced emphysema and suppressed the lung inflammation. In conclusion, we provide evidence that necroptosis contributes to the pathogenesis of COPD. Targeting RIP3 and its downstream pathway may be an effective therapy for COPD.


Subject(s)
Necroptosis , Pulmonary Disease, Chronic Obstructive , Receptor-Interacting Protein Serine-Threonine Kinases , Adult , Aged , Aged, 80 and over , Animals , Apoptosis , Cell Line , Female , Humans , Lung/metabolism , Lung/pathology , Macrophages/metabolism , Male , Mice , Middle Aged , Necroptosis/genetics , Necroptosis/physiology , Pulmonary Disease, Chronic Obstructive/genetics , Pulmonary Disease, Chronic Obstructive/metabolism , Pulmonary Disease, Chronic Obstructive/pathology , Receptor-Interacting Protein Serine-Threonine Kinases/genetics , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Tobacco Smoke Pollution
2.
Int J Lang Commun Disord ; 56(3): 620-636, 2021 05.
Article in English | MEDLINE | ID: mdl-33818902

ABSTRACT

BACKGROUND: Despite evidence that Communication Partner Training (CPT) can enable health professionals to communicate more effectively with people with aphasia (PWA), an evidence-practice gap exists. To address this, a tailored implementation intervention was developed and trialled to improve health professionals' implementation of communication strategies in a subacute setting. AIMS: To explore the outcomes and perceived feasibility, acceptability and potential effectiveness of an iterative CPT implementation intervention on multidisciplinary healthcare professionals' communication with PWA. METHODS & PROCEDURES: The CPT implementation intervention was delivered to two groups of healthcare professionals (n = 6 and 7) approximately 6 months apart. The intervention underwent two iterations targeting emerging barriers to implementation success, with Group 2 receiving a modified version of the Group 1 intervention. A concurrent qualitative process evaluation was conducted to understand key factors determining implementation outcomes. Quantitative outcomes were recorded at baseline and 3-month follow-up, including the Measure of Skill in Supported Communication (MSC), a customized behavioural determinants survey mapped to the Theoretical Domains Framework (TDF) and the Organizational Readiness for Change survey. Focus groups and semi-structured interviews were conducted with health professional participants and the speech-language therapist trainer to explore perceptions of feasibility, acceptability and potential effectiveness. Content analysis was used to analyse the qualitative data, with categories and themes generated. OUTCOMES & RESULTS: The Group 2 implementation intervention was adapted based on feedback and reflections from Group 1 participants to incorporate more time for practice interactions and discussion during training, individual follow-up sessions and provision of accessible resources to aid communication attempts. There were greater improvements seen in the Group 2 outcomes on both the MSC and the TDF survey, suggesting that the iterative tailoring of the intervention was successful in addressing the barriers to change and led to improved implementation. The difference between the group's outcomes may also partly be explained by the impact of organizational readiness, which decreased during Group 1's implementation period. Despite similar themes emerging from the stakeholder perspectives in both groups (training factors, implementation facilitators, implementation barriers, and changes in knowledge and practice), these diverted in ways which served to explain the different implementation outcomes. CONCLUSIONS & IMPLICATIONS: An iteratively adapted CPT implementation intervention targeting healthcare professionals' use of supported communication strategies was feasible and acceptable for most participants. The implementation intervention was potentially effective in changing participants' communication with PWA, particularly for Group 2. Future CPT implementation efforts should continue to incorporate stakeholder input and tailor strategies to the organizational context, and measure whether outcomes are sustained in the long term. What this paper adds What is already known on the subject CPT is a complex intervention that can improve communication access and outcomes for PWA. However, there are barriers to both delivering CPT programmes to staff, and for staff in modifying their communication behaviours. Despite increasing efforts to improve CPT implementation, it remains largely unclear whether CPT implementation interventions are effective in improving interactions between staff and patients, and what elements of an implementation intervention result in changed behaviour. What this study adds to existing knowledge This study showed that adopting an iterative, barriers-focused approach to implementation facilitated practice change for one of the groups that participated in the programme. Incorporating stakeholder feedback in an ongoing way led to improvements in feasibility, acceptability and potential effectiveness, with several of the main barriers being effectively addressed by the intervention. Some key mechanisms of change were identified. What are the potential or actual clinical implications of this work It is necessary to develop active, targeted implementation strategies to support healthcare professionals to modify their communication, monitor implementation barriers as they arise and modify behaviour-change strategies accordingly. In a similar context, it is suggested that CPT implementation interventions should incorporate the use of audit feedback, physical resources and educational lectures paired with interactions with PWA in order to bring about change, with ongoing support and facilitation.


Subject(s)
Aphasia , Communication , Delivery of Health Care , Health Personnel , Humans , Pilot Projects
3.
JCI Insight ; 4(19)2019 10 03.
Article in English | MEDLINE | ID: mdl-31578312

ABSTRACT

Dysregulated proinflammatory cytokine release has been implicated in the pathogenesis of several life-threatening acute lung illnesses such as pneumonia, sepsis, and acute respiratory distress syndrome. Suppressors of cytokine signaling proteins, particularly SOCS2, have recently been described as antiinflammatory mediators. However, the regulation of SOCS2 protein has not been described. Here we describe a mechanism of SOCS2 regulation by the action of the ubiquitin E3 ligase KIAA0317. KIAA0317-mediated degradation of SOCS2 exacerbated inflammation in vitro, and depletion of KIAA0317 in vivo ameliorated pulmonary inflammation. KIAA0317-knockout mice exhibited resistance to LPS-induced pulmonary inflammation, while KIAA03017 reexpression mitigated this effect. We uncovered a small molecule inhibitor of KIAA0317 protein (BC-1365) that prevented SOCS2 degradation and attenuated LPS- and P. aeruginosa-induced lung inflammation in vivo. These studies show KIAA0317 to be a critical mediator of pulmonary inflammation through its degradation of SOCS2 and a potential candidate target for therapeutic inhibition.


Subject(s)
Lung/metabolism , Pneumonia/metabolism , Suppressor of Cytokine Signaling Proteins/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Adult , Aged , Animals , Cytokines/metabolism , Female , Humans , Immunity, Innate , Lung/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Molecular Docking Simulation , Pneumonia/immunology , Pneumonia/pathology , Protein Binding , Transcriptome
5.
Am J Respir Crit Care Med ; 196(3): 353-363, 2017 08 01.
Article in English | MEDLINE | ID: mdl-28345958

ABSTRACT

RATIONALE: Macrophage elastase (matrix metalloproteinase [MMP]-12) is a potent protease that contributes to the lung destruction that accompanies cigarette smoking; it simultaneously inhibits lung tumor angiogenesis and metastasis by catalyzing the formation of antiangiogenic peptides. Recent studies have revealed novel nonproteolytic functions of MMP12, including antimicrobial activity through a peptide within its C-terminal domain (CTD). OBJECTIVES: To determine whether the MMP12 CTD contributes to its antitumor activity in lung cancer. METHODS: We used recombinant MMP12 peptide fragments, including its catalytic domain, CTD, and a 20 amino acid peptide within the CTD (SR20), in an in vitro system to delineate their effects on non-small cell lung cancer cell proliferation and apoptosis. We translated our findings to two murine models of lung cancer, including orthotopic human xenograft and KrasLSL/G12D mouse models of lung cancer. MEASUREMENTS AND MAIN RESULTS: We show that SR20 triggers tumor apoptosis by up-regulation of gene expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its receptor, death receptor 4, sensitizing cells to an autocrine loop of TRAIL-mediated cell death. We then demonstrate the therapeutic efficacy of SR20 against two murine models of lung cancer. CONCLUSIONS: The MMP12 CTD initiates TRAIL-mediated tumor cell death through its conserved SR20 peptide.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Lung Neoplasms/metabolism , Matrix Metalloproteinase 12/metabolism , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism , TNF-Related Apoptosis-Inducing Ligand/metabolism , Animals , Apoptosis , Cell Death , Cell Line, Tumor , Cell Proliferation , Disease Models, Animal , Humans , Mice , Up-Regulation
6.
Am J Respir Cell Mol Biol ; 56(4): 488-496, 2017 04.
Article in English | MEDLINE | ID: mdl-28085498

ABSTRACT

Pulmonary hypertension (PH) is associated with features of obesity and metabolic syndrome that translate to the induction of PH by chronic high-fat diet (HFD) in some inbred mouse strains. We conducted a genome-wide association study (GWAS) to identify candidate genes associated with susceptibility to HFD-induced PH. Mice from 36 inbred and wild-derived strains were fed with regular diet or HFD for 20 weeks beginning at 6-12 weeks of age, after which right ventricular (RV) and left ventricular (LV) end-systolic pressure (ESP) and maximum pressure (MaxP) were measured by cardiac catheterization. We tested for association of RV MaxP and RV ESP and identified genomic regions enriched with nominal associations to both of these phenotypes. We excluded genomic regions if they were also associated with LV MaxP, LV ESP, or body weight. Genes within significant regions were scored based on the shortest-path betweenness centrality, a measure of network connectivity, of their human orthologs in a gene interaction network of human PH-related genes. WSB/EiJ, NON/ShiLtJ, and AKR/J mice had the largest increases in RV MaxP after high-fat feeding. Network-based scoring of GWAS candidates identified epidermal growth factor receptor (Egfr) as having the highest shortest-path betweenness centrality of GWAS candidates. Expression studies of lung homogenate showed that EGFR expression is increased in the AKR/J strain, which developed a significant increase in RV MaxP after high-fat feeding as compared with C57BL/6J, which did not. Our combined GWAS and network-based approach adds evidence for a role for Egfr in murine PH.


Subject(s)
ErbB Receptors/metabolism , Genome-Wide Association Study , Hypertension, Pulmonary/genetics , Animals , Diet, High-Fat , Gene Regulatory Networks , Genetic Predisposition to Disease , Heart Ventricles/physiopathology , Hemodynamics , Humans , Hypertension, Pulmonary/physiopathology , Male , Mice , Mice, Inbred AKR , Mice, Inbred C57BL
7.
Crit Care ; 18(5): 469, 2014 Sep 03.
Article in English | MEDLINE | ID: mdl-25182529

ABSTRACT

INTRODUCTION: Sepsis and other infections are associated with late cardiovascular events. Although persistent inflammation is implicated, a causal relationship has not been established. We tested whether sepsis causes vascular inflammation and accelerates atherosclerosis. METHODS: We performed prospective, randomized animal studies at a university research laboratory involving adult male ApoE-deficient (ApoE-/-) and young C57B/L6 wild-type (WT) mice. In the primary study conducted to determine whether sepsis accelerates atherosclerosis, we fed ApoE-/- mice (N = 46) an atherogenic diet for 4 months and then performed cecal ligation and puncture (CLP), followed by antibiotic therapy and fluid resuscitation or a sham operation. We followed mice for up to an additional 5 months and assessed atheroma in the descending aorta and root of the aorta. We also exposed 32 young WT mice to CLP or sham operation and followed them for 5 days to determine the effects of sepsis on vascular inflammation. RESULTS: ApoE-/- mice that underwent CLP had reduced activity during the first 14 days (38% reduction compared to sham; P < 0.001) and sustained weight loss compared to the sham-operated mice (-6% versus +9% change in weight after CLP or sham surgery to 5 months; P < 0.001). Despite their weight loss, CLP mice had increased atheroma (46% by 3 months and 41% increase in aortic surface area by 5 months; P = 0.03 and P = 0.004, respectively) with increased macrophage infiltration into atheroma as assessed by immunofluorescence microscopy (0.52 relative fluorescence units (rfu) versus 0.97 rfu; P = 0.04). At 5 months, peritoneal cultures were negative; however, CLP mice had elevated serum levels of interleukin 6 (IL-6) and IL-10 (each at P < 0.05). WT mice that underwent CLP had increased expression of intercellular adhesion molecule 1 in the aortic lumen versus sham at 24 hours (P = 0.01) that persisted at 120 hours (P = 0.006). Inflammatory and adhesion genes (tumor necrosis factor α, chemokine (C-C motif) ligand 2 and vascular cell adhesion molecule 1) and the adhesion assay, a functional measure of endothelial activation, were elevated at 72 hours and 120 hours in mice that underwent CLP versus sham-operations (all at P <0.05). CONCLUSIONS: Using a combination of existing murine models for atherosclerosis and sepsis, we found that CLP, a model of intra-abdominal sepsis, accelerates atheroma development. Accelerated atheroma burden was associated with prolonged systemic, endothelial and intimal inflammation and was not explained by ongoing infection. These findings support observations in humans and demonstrate the feasibility of a long-term follow-up murine model of sepsis.


Subject(s)
Atherosclerosis/etiology , Sepsis/complications , Abdomen , Animals , Aorta/pathology , Atherosclerosis/blood , Atherosclerosis/pathology , Biomarkers/blood , Cell Adhesion Molecules/metabolism , Cytokines/blood , Cytokines/genetics , Disease Models, Animal , Gene Expression , Male , Mice, Inbred C57BL , Prospective Studies , RNA, Messenger/metabolism , Random Allocation , Sepsis/blood , Weight Loss
8.
J Int Neuropsychol Soc ; 14(2): 181-91, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18282316

ABSTRACT

We investigated verb generation in children with spina bifida meningomyelocele (SBM; n = 55) and in typically developing controls (n = 32). Participants completed 6 blocks (40 trials each) of a task requiring them to produce a semantically related verb in response to a target noun and an additional 40 trials on which they were simply required to read target nouns aloud. After controlling for reading response time, groups did not differ significantly in verb generation response time or learning. Children with SBM produced more non-verb errors than controls and tended to repeat their mistakes over blocks. Verb generation performance was associated with brain volume measures in participants with SBM. Congenital cerebellar dysmorphology is associated with impaired performance in verb generation accuracy, although not with increased response times to produce verbs


Subject(s)
Language , Spinal Dysraphism/physiopathology , Verbal Behavior/physiology , Adolescent , Adult , Brain/pathology , Child , Female , Functional Laterality , Humans , Male , Reaction Time/physiology , Reading , Spinal Dysraphism/pathology
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