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1.
J Asthma Allergy ; 17: 911-928, 2024.
Article in English | MEDLINE | ID: mdl-39346093

ABSTRACT

Introduction: Management of difficult-to-treat asthma is particularly challenging in people with elevated body mass index (BMI). Our randomised controlled trial of pulmonary rehabilitation (PR) showed improved outcomes at 8 weeks. Here we assess immediate and one-year effects of asthma-tailored PR in participants with difficult-to-treat asthma and BMI ≥25 kg/m2, and identify response predictors. Methods: A prospective observational study of PR, tailored to asthma, comparing outcomes at baseline (V1), immediately after 8 weeks of PR (V2), and at 1 year (V3). Baseline characteristics were compared in responders/non-responders defined by achievement of minimum clinically important difference (MCID) for asthma control questionnaire (ACQ6) (0.5) at 8 weeks and 1 year. Results: Of 92 participants, 56 attended V2 and 45 attended V3. Mean age was 60 (SD 13) years, 60% were female, and median (IQR) BMI was 33.8 (29.5-38.7) kg/m2. At V1, V2, and V3, respectively, there were significant differences in ACQ6 (mean (95% CI): 2.5 (2.1-2.9), 2.2 (1.8-2.5), and 2.3 (1.9-2.7), p<0.003), Borg breathlessness score post-6-minute walk test (median (IQR): 2 (0.5-3), 1 (0-2), and 1 (0.5-2), p<0.035), and annualised exacerbations requiring prednisolone (median (IQR): 3 (2-5), 0 (0-4.7), and 1.5 (0-4.2), p<0.003). A total of 27/56 (48%) had improvements >MCID for ACQ6 at V2 and 16 (33%) at V3. Participants with higher ACQ6 scores at baseline (suggesting poorer asthma control) were more likely to achieve MCID. Baseline BMI, within the range studied, was not predictive. Conclusion: Pulmonary rehabilitation induced improvements in asthma-related outcomes including perception of breathlessness, asthma control, and exacerbation frequency at 1 year. Those with poorer baseline asthma control were more likely to benefit.

2.
bioRxiv ; 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39282400

ABSTRACT

Background: Protein-tyrosine-phosphatase CD45 is exclusively expressed in all nucleated cells of the hematopoietic system but is rarely expressed in endothelial cells. Interestingly, our recent study indicated that activation of the endogenous CD45 promoter in human endothelial colony forming cells (ECFCs) induced expression of multiple EndoMT marker genes. However, the detailed molecular mechanisms underlying CD45 that drive EndoMT and the therapeutic potential of manipulation of CD45 expression in atherosclerosis are entirely unknown. Method: We generated a tamoxifen-inducible EC-specific CD45 deficient mouse strain (EC-iCD45KO) in an ApoE-deficient (ApoE-/-) background and fed with a Western diet (C57BL/6) for atherosclerosis and molecular analyses. We isolated and enriched mouse aortic endothelial cells with CD31 beads to perform single-cell RNA sequencing. Biomedical, cellular, and molecular approaches were utilized to investigate the role of endothelial CD45-specific deletion in the prevention of EndoMT in ApoE-/- model of atherosclerosis. Results: Single-cell RNA sequencing revealed that loss of endothelial CD45 inhibits EndoMT marker expression and transforming growth factor-ß signaling in atherosclerotic mice. which is associated with the reductions of lesions in the ApoE-/- mouse model. Mechanistically, the loss of endothelial cell CD45 results in increased KLF2 expression, which inhibits transforming growth factor-ß signaling and EndoMT. Consistently, endothelial CD45 deficient mice showed reduced lesion development, plaque macrophages, and expression of cell adhesion molecules when compared to ApoE-/- controls. Conclusions: These findings demonstrate that the loss of endothelial CD45 protects against EndoMT-driven atherosclerosis, promoting KLF2 expression while inhibiting TGFß signaling and EndoMT markers. Thus, targeting endothelial CD45 may be a novel therapeutic strategy for EndoMT and atherosclerosis.

3.
bioRxiv ; 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39253478

ABSTRACT

Rationale: Low density cholesterol receptor (LDLR) in the liver is critical for the clearance of low-density lipoprotein cholesterol (LDL-C) in the blood. In atherogenic conditions, proprotein convertase subtilisin/kexin 9 (PCSK9) secreted by the liver, in a nonenzymatic fashion, binds to LDLR on the surface of hepatocytes, preventing its recycling and enhancing its degradation in lysosomes, resulting in reduced LDL-C clearance. Our recent studies demonstrate that epsins, a family of ubiquitin-binding endocytic adaptors, are critical regulators of atherogenicity. Given the fundamental contribution of circulating LDL-C to atherosclerosis, we hypothesize that liver epsins promote atherosclerosis by controlling LDLR endocytosis and degradation. Objective: We will determine the role of liver epsins in promoting PCSK9-mediated LDLR degradation and hindering LDL-C clearance to propel atherosclerosis. Methods and Results: We generated double knockout mice in which both paralogs of epsins, namely, epsin-1 and epsin-2, are specifically deleted in the liver (Liver-DKO) on an ApoE -/- background. We discovered that western diet (WD)-induced atherogenesis was greatly inhibited, along with diminished blood cholesterol and triglyceride levels. Mechanistically, using scRNA-seq analysis on cells isolated from the livers of ApoE-/- and ApoE-/- /Liver-DKO mice on WD, we found lipogenic Alb hi hepatocytes to glycogenic HNF4α hi hepatocytes transition in ApoE-/- /Liver-DKO. Subsequently, gene ontology analysis of hepatocyte-derived data revealed elevated pathways involved in LDL particle clearance and very-low-density lipoprotein (VLDL) particle clearance under WD treatment in ApoE-/- /Liver-DKO, which was coupled with diminished plasma LDL-C levels. Further analysis using the MEBOCOST algorithm revealed enhanced communication score between LDLR and cholesterol, suggesting elevated LDL-C clearance in the ApoE-/- Liver-DKO mice. In addition, we showed that loss of epsins in the liver upregulates of LDLR protein level. We further showed that epsins bind LDLR via the ubiquitin-interacting motif (UIM), and PCSK9-triggered LDLR degradation was abolished by depletion of epsins, preventing atheroma progression. Finally, our therapeutic strategy, which involved targeting liver epsins with nanoparticle-encapsulated siRNAs, was highly efficacious at inhibiting dyslipidemia and impeding atherosclerosis. Conclusions: Liver epsins promote atherogenesis by mediating PCSK9-triggered degradation of LDLR, thus raising the circulating LDL-C levels. Targeting epsins in the liver may serve as a novel therapeutic strategy to treat atherosclerosis by suppression of PCSK9-mediated LDLR degradation.

4.
bioRxiv ; 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39253510

ABSTRACT

Diabetes mellitus can cause impaired and delayed wound healing, leading to lower extremity amputations; however, the mechanisms underlying the regulation of vascular endothelial growth factor (VEGF)-dependent angiogenesis remain uncertain and could reveal new therapeutic targets. In our study, the molecular underpinnings of endothelial dysfunction in diabetes were investigated, focusing on the roles of Disabled-2 (Dab2) and Forkhead Box M1 (FoxM1) in VEGF receptor 2 (VEGFR2) signaling and endothelial cell (EC) function. Bulk RNA-sequencing analysis identified significant downregulation of Dab2 in high concentrations glucose treated primary mouse skin ECs, simulating hyperglycemic conditions in diabetes mellitus. In diabetic mice with a genetic EC deficiency of Dab2 angiogenesis was reduced in vivo and in vitro when compared with wild-type mice. Restoration of Dab2 expression by injected mRNA-containing lipid nanoparticles rescued impaired angiogenesis and wound healing in diabetic mice. At the same time, FoxM1 was downregulated in skin ECs subjected to high glucose conditions as determined by RNA-sequencing analysis. FoxM1 was found to bind to the Dab2 promoter, regulating its expression and influencing VEGFR2 signaling. The FoxM1 inhibitor FDI-6 reduced Dab2 expression and phosphorylation of VEGFR2. These findings indicate that restoring Dab2 expression through targeted therapies can enhance angiogenesis and wound repair in diabetes. To explore this therapeutic potential, we tested LyP-1-conjugated lipid nanoparticles (LNPs) containing Dab2 or control mRNAs to target ECs and found the former significantly improved wound healing and angiogenesis in diabetic mice. This study provides evidence of the crucial roles of Dab2 and FoxM1 in diabetic endothelial dysfunction and establishes targeted delivery as a promising treatment for diabetic vascular complications.

5.
bioRxiv ; 2024 Aug 26.
Article in English | MEDLINE | ID: mdl-39131381

ABSTRACT

Smooth muscle cells in major arteries play a crucial role in regulating coronary artery disease. Conversion of smooth muscle cells into other adverse cell types in the artery propels the pathogenesis of the disease. Curtailing artery plaque buildup by modulating smooth muscle cell reprograming presents us a new opportunity to thwart coronary artery disease. Here, our report how Epsins, a family of endocytic adaptor proteins oversee the smooth muscle cell reprograming by influencing master regulators OCT4 and KLF4. Using single-cell RNA sequencing, we characterized the phenotype of modulated smooth muscle cells in mouse atherosclerotic plaque and found that smooth muscle cells lacking epsins undergo profound reprogramming into not only beneficial myofibroblasts but also endothelial cells for injury repair of diseased endothelium. Our work lays concrete groundwork to explore an uncharted territory as we show that depleting Epsins bolsters smooth muscle cells reprograming to endothelial cells by augmenting OCT4 activity but restrain them from reprograming to harmful foam cells by destabilizing KLF4, a master regulator of adverse reprograming of smooth muscle cells. Moreover, the expression of Epsins in smooth muscle cells positively correlates with the severity of both human and mouse coronary artery disease. Integrating our scRNA-seq data with human Genome-Wide Association Studies (GWAS) identifies pivotal roles Epsins play in smooth muscle cells in the pathological process leading to coronary artery disease. Our findings reveal a previously unexplored direction for smooth muscle cell phenotypic modulation in the development and progression of coronary artery disease and unveil Epsins and their downstream new targets as promising novel therapeutic targets for mitigating metabolic disorders.

7.
Vascul Pharmacol ; 155: 107368, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38548093

ABSTRACT

Atherosclerosis, a chronic systemic inflammatory condition, is implicated in most cardiovascular ischemic events. The pathophysiology of atherosclerosis involves various cell types and associated processes, including endothelial cell activation, monocyte recruitment, smooth muscle cell migration, involvement of macrophages and foam cells, and instability of the extracellular matrix. The process of endothelial-to-mesenchymal transition (EndoMT) has recently emerged as a pivotal process in mediating vascular inflammation associated with atherosclerosis. This transition occurs gradually, with a significant portion of endothelial cells adopting an intermediate state, characterized by a partial loss of endothelial-specific gene expression and the acquisition of "mesenchymal" traits. Consequently, this shift disrupts endothelial cell junctions, increases vascular permeability, and exacerbates inflammation, creating a self-perpetuating cycle that drives atherosclerotic progression. While endothelial cell dysfunction initiates the development of atherosclerosis, autophagy, a cellular catabolic process designed to safeguard cells by recycling intracellular molecules, is believed to exert a significant role in plaque development. Identifying the pathological mechanisms and molecular mediators of EndoMT underpinning endothelial autophagy, may be of clinical relevance. Here, we offer new insights into the underlying biology of atherosclerosis and present potential molecular mechanisms of atherosclerotic resistance and highlight potential therapeutic targets.


Subject(s)
Atherosclerosis , Autophagy , Endothelial Cells , Signal Transduction , Humans , Atherosclerosis/pathology , Atherosclerosis/metabolism , Atherosclerosis/physiopathology , Atherosclerosis/genetics , Animals , Endothelial Cells/pathology , Endothelial Cells/metabolism , Epithelial-Mesenchymal Transition , Plaque, Atherosclerotic , Phenotype
8.
Allergy Asthma Clin Immunol ; 20(1): 5, 2024 Jan 14.
Article in English | MEDLINE | ID: mdl-38221641

ABSTRACT

INTRODUCTION: Poor sleep health is associated with increased asthma morbidity and mortality. Accelerometers have been validated to assess sleep parameters though studies using this method in patients with asthma are sparse and none have compared mild to difficult-to-treat asthma populations. METHODS: We performed a retrospective analysis from two recent in-house trials comparing sleep metrics between patients with mild and difficult-to-treat asthma. Participants wore accelerometers for 24-hours/day for seven days. RESULTS: Of 124 participants (44 mild, 80 difficult-to-treat), no between-group differences were observed in sleep-window, sleep-time, sleep efficiency or wake time. Sleep-onset time was ~ 40 min later in the difficult-to-treat group (p = 0.019). DISCUSSION: Broadly, we observed no difference in accelerometer-derived sleep-metrics between mild and difficult-to-treat asthma. This is the largest analysis of accelerometer-derived sleep parameters in asthma and the first comparing groups by asthma severity. Sleep-onset initiation may be delayed in difficult-to-treat asthma but a dedicated study is needed to confirm.

9.
Article in English | MEDLINE | ID: mdl-37217282

ABSTRACT

Circulating vascular endothelial growth factor (VEGF) ligands and receptors are central regulators of vasculogenesis, angiogenesis, and lymphangiogenesis. In response to VEGF ligand binding, VEGF receptor tyrosine kinases initiate the chain of events that transduce extracellular signals into endothelial cell responses such as survival, proliferation, and migration. These events are controlled by intricate cellular processes that include the regulation of gene expression at multiple levels, interactions of numerous proteins, and intracellular trafficking of receptor-ligand complexes. Endocytic uptake and transport of macromolecular complexes through the endosome-lysosome system helps fine-tune endothelial cell responses to VEGF signals. Clathrin-dependent endocytosis remains the best understood means of macromolecular entry into cells, although the importance of non-clathrin-dependent pathways is increasingly recognized. Many of these endocytic events rely on adaptor proteins that coordinate internalization of activated cell-surface receptors. In the endothelium of both blood and lymphatic vessels, epsins 1 and 2 are functionally redundant adaptors involved in receptor endocytosis and intracellular sorting. These proteins are capable of binding both lipids and proteins and are important for promoting curvature of the plasma membrane as well as binding ubiquitinated cargo. Here, we discuss the role of epsin proteins and other endocytic adaptors in governing VEGF signaling in angiogenesis and lymphangiogenesis and discuss their therapeutic potential as molecular targets.


Subject(s)
Lymphangiogenesis , Vascular Endothelial Growth Factor A , Humans , Lymphangiogenesis/physiology , Ligands , Adaptor Proteins, Vesicular Transport/genetics , Adaptor Proteins, Vesicular Transport/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Endocytosis , Clathrin/metabolism
10.
bioRxiv ; 2023 May 18.
Article in English | MEDLINE | ID: mdl-37293078

ABSTRACT

Alanyl-transfer RNA synthetase 2 (AARS2) is a nuclear encoded mitochondrial tRNA synthetase that is responsible for charging of tRNA-Ala with alanine during mitochondrial translation. Homozygous or compound heterozygous mutations in the Aars2 gene, including those affecting its splicing, are linked to infantile cardiomyopathy in humans. However, how Aars2 regulates heart development, and the underlying molecular mechanism of heart disease remains unknown. Here, we found that poly(rC) binding protein 1 (PCBP1) interacts with the Aars2 transcript to mediate its alternative splicing and is critical for the expression and function of Aars2. Cardiomyocyte-specific deletion of Pcbp1 in mice resulted in defects in heart development that are reminiscent of human congenital cardiac defects, including noncompaction cardiomyopathy and a disruption of the cardiomyocyte maturation trajectory. Loss of Pcbp1 led to an aberrant alternative splicing and a premature termination of Aars2 in cardiomyocytes. Additionally, Aars2 mutant mice with exon-16 skipping recapitulated heart developmental defects observed in Pcbp1 mutant mice. Mechanistically, we found dysregulated gene and protein expression of the oxidative phosphorylation pathway in both Pcbp1 and Aars2 mutant hearts; these date provide further evidence that the infantile hypertrophic cardiomyopathy associated with the disorder oxidative phosphorylation defect type 8 (COXPD8) is mediated by Aars2. Our study therefore identifies Pcbp1 and Aars2 as critical regulators of heart development and provides important molecular insights into the role of disruptions in metabolism on congenital heart defects.

11.
Nat Commun ; 14(1): 1595, 2023 03 22.
Article in English | MEDLINE | ID: mdl-36949106

ABSTRACT

The regulation of the informational flow from the mitochondria to the nucleus (mitonuclear communication) is not fully characterized in the heart. We have determined that mitochondrial ribosomal protein S5 (MRPS5/uS5m) can regulate cardiac function and key pathways to coordinate this process during cardiac stress. We demonstrate that loss of Mrps5 in the developing heart leads to cardiac defects and embryonic lethality while postnatal loss induces cardiac hypertrophy and heart failure. The structure and function of mitochondria is disrupted in Mrps5 mutant cardiomyocytes, impairing mitochondrial protein translation and OXPHOS. We identify Klf15 as a Mrps5 downstream target and demonstrate that exogenous Klf15 is able to rescue the overt defects and re-balance the cardiac metabolome. We further show that Mrps5 represses Klf15 expression through c-myc, together with the metabolite L-phenylalanine. This critical role for Mrps5 in cardiac metabolism and mitonuclear communication highlights its potential as a target for heart failure therapies.


Subject(s)
Heart Failure , Protein Biosynthesis , Humans , Cardiomegaly/genetics , Cardiomegaly/metabolism , Heart Failure/genetics , Heart Failure/metabolism , Myocytes, Cardiac/metabolism , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism
12.
Chest ; 163(5): 1026-1037, 2023 05.
Article in English | MEDLINE | ID: mdl-36649753

ABSTRACT

BACKGROUND: Obesity is often associated with uncontrolled, difficult-to-treat asthma and increased morbidity and mortality. Previous studies suggest that weight loss may improve asthma outcomes, but with heterogenous asthma populations studied and unclear consensus on the optimal method of weight management. The Counterweight-Plus Programme (CWP) for weight management is an evidence-based, dietitian-led total diet replacement (TDR) program. RESEARCH QUESTION: Can use of the CWP compared with usual care (UC) improve asthma control and quality of life in patients with difficult-to-treat asthma and obesity? STUDY DESIGN AND METHODS: We conducted a 1:1 (CWP to UC) randomized, controlled single-center trial in adults with difficult-to-treat asthma and BMI of ≥ 30 kg/m2. The CWP was a 12-week TDR phase (800 kcal/d low-energy formula) followed by stepwise food reintroduction and weight loss maintenance for up to 1 year. The primary outcome was the change in Asthma Control Questionnaire 6 (ACQ6) score over 16 weeks. The secondary outcome was change in Asthma Quality of Life Questionnaire (AQLQ) score. RESULTS: Thirty-five participants were randomized (36 screened) and 33 attended the 16-week follow-up (n = 17 in the CWP group, n = 16 in the UC group). Overall, mean ACQ6 score at baseline was 2.8 (95% CI, 2.4-3.1). Weight loss was greater in the CWP than UC group (mean difference, -12.1 kg; 95% CI, -16.9 to -7.4; P < .001). ACQ6 score improved more in the CWP than UC group (mean difference, -0.69; 95% CI, -1.37 to -0.01; P = .048). A larger proportion of participants achieved the minimal clinically important difference in ACQ6 score with CWP than with UC (53% vs 19%; P = .041; Number needed to treat, 3 [95% CI, 1.5-26.9]). AQLQ score improvement was greater in the CWP than UC group (mean difference, 0.76; 95% CI, 0.18-1.34; P = .013). INTERPRETATION: Using a structured weight management program results in clinically important improvements in asthma control and quality of life over 16 weeks compared with UC in adults with difficult-to-treat asthma and obesity. This generalizable program is easy to deliver for this challenging phenotype. Longer-term outcomes continue to be studied. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT03858608; URL: www. CLINICALTRIALS: gov.


Subject(s)
Asthma , Weight Reduction Programs , Humans , Quality of Life , Weight Reduction Programs/methods , Feasibility Studies , Obesity/complications , Obesity/therapy , Asthma/complications , Asthma/therapy , Diet , Weight Loss
13.
J Allergy Clin Immunol Pract ; 11(4): 1233-1242.e5, 2023 04.
Article in English | MEDLINE | ID: mdl-36621603

ABSTRACT

BACKGROUND: Approximately 5% to 10% of patients with asthma have severe disease, with a consistent preponderance in females. Current asthma guidelines recommend stepwise treatment to achieve symptom control with no differential treatment considerations for either sex. OBJECTIVE: To examine whether patient sex affects outcomes when using a composite T2-biomarker score to adjust corticosteroid (CS) treatment in patients with severe asthma compared with standard care. METHODS: This is a post hoc analysis, stratifying patient outcomes by sex, of a 48-week, multicenter, randomized controlled clinical trial comparing a biomarker-defined treatment algorithm with standard care. The primary outcome was the proportion of patients with a reduction in CS treatment (inhaled and oral corticosteroids). Secondary outcomes included exacerbation rates, hospital admissions, and lung function. RESULTS: Of the 301 patients randomized, 194 (64.5%) were females and 107 (35.5%) were males. The biomarker algorithm led to a greater proportion of females being on a lower CS dose versus standard care, which was not seen in males (effect estimate: females, 3.57; 95% CI, 1.14-11.18 vs males, 0.54; 95% CI, 0.16-1.80). In T2-biomarker-low females, reducing CS dose was not associated with increased exacerbations. Females scored higher in all domains of the 7-item Asthma Control Questionnaire, apart from FEV1, but with no difference when adjusted for body mass index/anxiety and/or depression. Dissociation between symptoms and T2 biomarkers were noted in both sexes, with a higher proportion of females being symptom high/T2-biomarker low (22.8% vs 15.6%; P = .0002), whereas males were symptom low/T2-biomarker high (22.3% vs 11.4%; P < .0001). CONCLUSIONS: This exploratory post hoc analysis identified that females achieved a greater benefit from biomarker-directed CS optimization versus symptom-directed treatment.


Subject(s)
Anti-Asthmatic Agents , Asthma , Male , Female , Humans , Adrenal Cortex Hormones , Drug Therapy, Combination , Biomarkers
14.
Circulation ; 147(8): 669-685, 2023 02 21.
Article in English | MEDLINE | ID: mdl-36591786

ABSTRACT

BACKGROUND: Epsin endocytic adaptor proteins are implicated in the progression of atherosclerosis; however, the underlying molecular mechanisms have not yet been fully defined. In this study, we determined how epsins enhance endothelial-to-mesenchymal transition (EndoMT) in atherosclerosis and assessed the efficacy of a therapeutic peptide in a preclinical model of this disease. METHODS: Using single-cell RNA sequencing combined with molecular, cellular, and biochemical analyses, we investigated the role of epsins in stimulating EndoMT using knockout in Apoe-/- and lineage tracing/proprotein convertase subtilisin/kexin type 9 serine protease mutant viral-induced atherosclerotic mouse models. The therapeutic efficacy of a synthetic peptide targeting atherosclerotic plaques was then assessed in Apoe-/- mice. RESULTS: Single-cell RNA sequencing and lineage tracing revealed that epsins 1 and 2 promote EndoMT and that the loss of endothelial epsins inhibits EndoMT marker expression and transforming growth factor-ß signaling in vitro and in atherosclerotic mice, which is associated with smaller lesions in the Apoe-/- mouse model. Mechanistically, the loss of endothelial cell epsins results in increased fibroblast growth factor receptor-1 expression, which inhibits transforming growth factor-ß signaling and EndoMT. Epsins directly bind ubiquitinated fibroblast growth factor receptor-1 through their ubiquitin-interacting motif, which results in endocytosis and degradation of this receptor complex. Consequently, administration of a synthetic ubiquitin-interacting motif-containing peptide atheroma ubiquitin-interacting motif peptide inhibitor significantly attenuates EndoMT and progression of atherosclerosis. CONCLUSIONS: We conclude that epsins potentiate EndoMT during atherogenesis by increasing transforming growth factor-ß signaling through fibroblast growth factor receptor-1 internalization and degradation. Inhibition of EndoMT by reducing epsin-fibroblast growth factor receptor-1 interaction with a therapeutic peptide may represent a novel treatment strategy for atherosclerosis.


Subject(s)
Atherosclerosis , Transforming Growth Factor beta , Mice , Animals , Fibroblast Growth Factors , Apolipoproteins E , Atherosclerosis/genetics , Receptors, Fibroblast Growth Factor , Transforming Growth Factors , Ubiquitins
15.
Circ Res ; 132(1): e22-e42, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36444722

ABSTRACT

BACKGROUND: Excess cholesterol accumulation in lesional macrophages elicits complex responses in atherosclerosis. Epsins, a family of endocytic adaptors, fuel the progression of atherosclerosis; however, the underlying mechanism and therapeutic potential of targeting Epsins remains unknown. In this study, we determined the role of Epsins in macrophage-mediated metabolic regulation. We then developed an innovative method to therapeutically target macrophage Epsins with specially designed S2P-conjugated lipid nanoparticles, which encapsulate small-interfering RNAs to suppress Epsins. METHODS: We used single-cell RNA sequencing with our newly developed algorithm MEBOCOST (Metabolite-mediated Cell Communication Modeling by Single Cell Transcriptome) to study cell-cell communications mediated by metabolites from sender cells and sensor proteins on receiver cells. Biomedical, cellular, and molecular approaches were utilized to investigate the role of macrophage Epsins in regulating lipid metabolism and transport. We performed this study using myeloid-specific Epsin double knockout (LysM-DKO) mice and mice with a genetic reduction of ABCG1 (ATP-binding cassette subfamily G member 1; LysM-DKO-ABCG1fl/+). The nanoparticles targeting lesional macrophages were developed to encapsulate interfering RNAs to treat atherosclerosis. RESULTS: We revealed that Epsins regulate lipid metabolism and transport in atherosclerotic macrophages. Inhibiting Epsins by nanotherapy halts inflammation and accelerates atheroma resolution. Harnessing lesional macrophage-specific nanoparticle delivery of Epsin small-interfering RNAs, we showed that silencing of macrophage Epsins diminished atherosclerotic plaque size and promoted plaque regression. Mechanistically, we demonstrated that Epsins bound to CD36 to facilitate lipid uptake by enhancing CD36 endocytosis and recycling. Conversely, Epsins promoted ABCG1 degradation via lysosomes and hampered ABCG1-mediated cholesterol efflux and reverse cholesterol transport. In a LysM-DKO-ABCG1fl/+ mouse model, enhanced cholesterol efflux and reverse transport due to Epsin deficiency was suppressed by the reduction of ABCG1. CONCLUSIONS: Our findings suggest that targeting Epsins in lesional macrophages may offer therapeutic benefits for advanced atherosclerosis by reducing CD36-mediated lipid uptake and increasing ABCG1-mediated cholesterol efflux.


Subject(s)
Atherosclerosis , Plaque, Atherosclerotic , Animals , Mice , Plaque, Atherosclerotic/metabolism , Macrophages/metabolism , Atherosclerosis/drug therapy , Atherosclerosis/genetics , Atherosclerosis/metabolism , Cholesterol/metabolism , ATP Binding Cassette Transporter 1/metabolism
16.
J Asthma ; 60(2): 385-392, 2023 02.
Article in English | MEDLINE | ID: mdl-35260034

ABSTRACT

OBJECTIVE: Type 2 (T2) inflammation offers a therapeutic target for biologics. Previous trials suggest obesity influences T2-biomarker levels in asthma, though have not accounted for key variables, e.g. inhaled (ICS)/oral corticosteroid (OCS) use. We hypothesized that body mass index (BMI) would affect T2-biomarker levels, after adjusting for covariates. METHODS: A retrospective analysis of data from two recent local trials of 153 participants with asthma (102 difficult-to-treat, 51 mild). Measurements included BMI, fractional exhaled nitric oxide (FeNO) and eosinophils. Correlation and regression analysis were performed for each biomarker to describe their relationship with BMI. Data was analyzed overall, and by asthma severity, T2-status and BMI tertile. RESULTS: Increasing BMI was associated with reduction in FeNO when stratified by BMI tertile (25 ppb lowest tertile, 18 ppb highest tertile; p = 0.014). Spearmans rank showed a negative correlation between BMI and FeNO in difficult-to-treat asthma (ρ= -0.309, p = 0.002). Linear regression adjusting for sex, age, smoking, atopy, allergic/perennial rhinitis, ICS and OCS confirmed BMI as a predictor of FeNO overall (ß= -2.848, p = 0.019). Eosinophils were reduced in the highest BMI tertile versus lowest in difficult-to-treat asthma (0.2x109/L, 0.3x109/L respectively; p = 0.02). CONCLUSIONS: Increasing BMI is associated with lower FeNO in asthma when adjusted for relevant covariates, including steroid use. There also appears to be an effect on eosinophil levels. Obesity, therefore, affects T2 biomarker levels with implications for disease endotyping and determination of eligibility for biologic therapy. Whether this is due to masking of underlying T2-high status or development of a truly T2-low endotype requires further research.


Subject(s)
Asthma , Humans , Asthma/drug therapy , Retrospective Studies , Nitric Oxide/analysis , Eosinophils , Obesity/complications , Adrenal Cortex Hormones/therapeutic use , Biomarkers/analysis , Breath Tests , Exhalation
17.
J Asthma ; 60(4): 824-834, 2023 04.
Article in English | MEDLINE | ID: mdl-35876843

ABSTRACT

OBJECTIVES: Patients with asthma may feel limited in physical activity (PA). Reduced PA has been demonstrated in asthmatics versus healthy controls, and increasing PA associated with improved asthma outcomes. Obesity is commonly found with difficult-to-control asthma and worsens outcomes. We compared PA levels in participants with difficult-to-control asthma and elevated body mass index (BMI) (DOW group) and two mild-moderate asthma groups: one with BMI <25 kg/m2 (MHW) and one with BMI ≥25 (MOW). METHODS: This cross-sectional study used 7-day recordings from wrist-worn accelerometers to compare PA between groups. Inactive time, light (LPA), moderate-vigorous PA (MVPA) were measured, along with two novel metrics: intensity gradient (IG) reflecting PA intensity, and average acceleration (AA) reflecting PA volume. PA parameters were compared using ANOVA or Kruskall-Wallis testing. Correlation and linear regression analyses explored associations between PA parameters and asthma outcomes. As AA was the PA parameter correlated most closely with asthma-related outcomes, an exploratory analysis compared outcomes in highest and lowest AA quartiles. RESULTS: 75 participants were recruited; 57 accelerometer readings were valid and included in analysis. Inactive time was significantly higher (p < 0.001), and LPA (p < 0.007), MVPA (p < 0.001), IG (p < 0.001) and AA (p < 0.001) all significantly lower in DOW versus MHW and MOW groups, even after adjusting for age and BMI. Quartiles based on AA had significantly different asthma profiles. CONCLUSIONS: Overweight/obese participants with difficult-to-control asthma performed less PA, and activity of reduced intensity and volume. Increased AA is associated with improvement in several asthma-related outcomes. Increased PA should be recommended to relevant patients.


Subject(s)
Asthma , Benchmarking , Humans , Body Mass Index , Cross-Sectional Studies , Exercise , Obesity , Patient Acuity , Accelerometry
18.
Arterioscler Thromb Vasc Biol ; 43(1): e1-e10, 2023 01.
Article in English | MEDLINE | ID: mdl-36453280

ABSTRACT

Lymphatic vessels are low-pressure, blind-ended tubular structures that play a crucial role in the maintenance of tissue fluid homeostasis, immune cell trafficking, and dietary lipid uptake and transport. Emerging research has indicated that the promotion of lymphatic vascular growth, remodeling, and function can reduce inflammation and diminish disease severity in several pathophysiologic conditions. In particular, recent groundbreaking studies have shown that lymphangiogenesis, which describes the formation of new lymphatic vessels from the existing lymphatic vasculature, can be beneficial for the alleviation and resolution of metabolic and cardiovascular diseases. Therefore, promoting lymphangiogenesis represents a promising therapeutic approach. This brief review summarizes the most recent findings related to the modulation of lymphatic function to treat metabolic and cardiovascular diseases such as obesity, myocardial infarction, atherosclerosis, and hypertension. We also discuss experimental and therapeutic approaches to enforce lymphatic growth and remodeling as well as efforts to define the molecular and cellular mechanisms underlying these processes.


Subject(s)
Lymphatic Vessels , Metabolic Diseases , Myocardial Infarction , Humans , Lymphangiogenesis , Lymphatic Vessels/metabolism , Heart , Myocardial Infarction/metabolism , Metabolic Diseases/metabolism
19.
Front Cardiovasc Med ; 9: 1031293, 2022.
Article in English | MEDLINE | ID: mdl-36247464

ABSTRACT

The efficient phagocytic clearance of dying cells and apoptotic cells is one of the processes that is essential for the maintenance of physiologic tissue function and homeostasis, which is termed "efferocytosis." Under normal conditions, "find me" and "eat me" signals are released by apoptotic cells to stimulate the engulfment and efferocytosis of apoptotic cells. In contrast, abnormal efferocytosis is related to chronic and non-resolving inflammatory diseases such as atherosclerosis. In the initial steps of atherosclerotic lesion development, monocyte-derived macrophages display efficient efferocytosis that restricts plaque progression; however, this capacity is reduced in more advanced lesions. Macrophage reprogramming as a result of the accumulation of apoptotic cells and augmented inflammation accounts for this diminishment of efferocytosis. Furthermore, defective efferocytosis plays an important role in necrotic core formation, which triggers plaque rupture and acute thrombotic cardiovascular events. Recent publications have focused on the essential role of macrophage efferocytosis in cardiac pathophysiology and have pointed toward new therapeutic strategies to modulate macrophage efferocytosis for cardiac tissue repair. In this review, we discuss the molecular and cellular mechanisms that regulate efferocytosis in vascular cells, including macrophages and other phagocytic cells and detail how efferocytosis-related molecules contribute to the maintenance of vascular hemostasis and how defective efferocytosis leads to the formation and progression of atherosclerotic plaques.

20.
BMC Pulm Med ; 22(1): 363, 2022 Sep 24.
Article in English | MEDLINE | ID: mdl-36153525

ABSTRACT

BACKGROUND: Difficult-to-control asthma associated with elevated body mass index (BMI) is challenging with limited treatment options. The effects of pulmonary rehabilitation (PR) in this population are uncertain. METHODS: This is a randomised controlled trial of an eight-week asthma-tailored PR programme versus usual care (UC) in participants with difficult-to-control asthma and BMI ≥ 25 kg/m2. PR comprised two hours of education and supervised exercise per week, with encouragement for two individual exercise sessions. Primary outcome was difference in change in Asthma Quality of Life Questionnaire (AQLQ) in PR versus UC groups between visits. Secondary outcomes included difference in change in Asthma Control Questionnaire-6 (ACQ6), and a responder analysis comparing proportion reaching minimum clinically important difference for AQLQ and ACQ6. RESULTS: 95 participants were randomised 1:1 to PR or UC. Median age was 54 years, 60% were female and median BMI was 33.8 kg/m2. Mean  (SD) AQLQ was 3.9 (+/-1.2) and median (IQR) ACQ6 2.8(1.8-3.6). 77 participants attended a second visit and had results analysed. Median (IQR) change in AQLQ was not significantly different: 0.3 (- 0.2 to 0.6) in PR and - 0.1 (- 0.5 to 0.4) in UC, p = 0.139. Mean change in ACQ6 was significantly different: - 0.4 (95% CI - 0.6 to - 0.2) in PR and 0 (- 0.3 to + 0.3) in UC, p = 0.015, but below minimum clinically important difference. In ACQ6 responder analysis, minimum clinically important difference was reached by 18 PR participants (54.5%) versus 10 UC (22.7%), p = 0.009. Dropout rate was 31% between visits in PR group, and time to completion was significantly prolonged in PR group at 94 (70-107) days versus 63 (56-73) in UC, p < 0.001. CONCLUSIONS: PR improved asthma control and reduced perceived breathlessness in participants with difficult-to-control asthma and elevated BMI. However, this format appears to be suboptimal for this population with high drop-out rates and prolonged time to completion. Trial registration Clinicaltrials.gov. ID NCT03630432. Retrospectively registered, submitted May 26th 2017, posted August 14th 2018.


Subject(s)
Asthma , Quality of Life , Asthma/rehabilitation , Body Mass Index , Dyspnea/rehabilitation , Exercise Therapy/methods , Female , Humans , Male , Middle Aged
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