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MedRxiv : the Preprint Server For... May 2024Hermansky-Pudlak syndrome (HPS) is a group of rare genetic disorders, with several subtypes leading to fatal adult-onset pulmonary fibrosis (PF) and no effective...
Hermansky-Pudlak syndrome (HPS) is a group of rare genetic disorders, with several subtypes leading to fatal adult-onset pulmonary fibrosis (PF) and no effective treatment. Circulating biomarkers detecting early PF have not been identified. We investigated whether endocannabinoids could serve as blood biomarkers of PF in HPS. We measured endocannabinoids in the serum of HPS, IPF, and healthy human subjects and in a mouse model of HPSPF. Pulmonary function tests (PFT) were correlated with endocannabinoid measurements. In a pale ear mouse model of bleomycin-induced HPSPF, serum endocannabinoid levels were measured with and without treatment with zevaquenabant (MRI-1867), a peripheral CB R and iNOS antagonist. In three separate cohorts, circulating anandamide levels were increased in HPS-1 patients with or without PF, compared to healthy volunteers. This increase was not observed in IPF patients or in HPS-3 patients, who do not have PF. Circulating anandamide (AEA) levels were negatively correlated with PFT. Furthermore, a longitudinal study over the course of 5-14 years with HPS-1 patients indicated that circulating AEA levels begin to increase with the fibrotic lung process even at the subclinical stages of HPSPF. In pale ear mice with bleomycin-induced HpsPF, serum AEA levels were significantly increased in the earliest stages of PF and remained elevated at a later fibrotic stage. Zevaquenabant treatment reduced the increased AEA levels and attenuated progression in bleomycin-induced HpsPF. Circulating AEA may be a prognostic blood biomarker for PF in HPS-1 patients. Further studies are indicated to evaluate endocannabinoids as potential surrogate biomarkers in progressive fibrotic lung diseases.
PubMed: 38798603
DOI: 10.1101/2024.05.16.24307300 -
Redox Report : Communications in Free... Dec 2024Deficiency of TOM5, a mitochondrial protein, causes organizing pneumonia (OP) in mice. The clinical significance and mechanisms of TOM5 in the pathogenesis of OP remain...
Deficiency of TOM5, a mitochondrial protein, causes organizing pneumonia (OP) in mice. The clinical significance and mechanisms of TOM5 in the pathogenesis of OP remain elusive. We demonstrated that TOM5 was significantly increased in the lung tissues of OP patients, which was positively correlated with the collagen deposition. In a bleomycin-induced murine model of chronic OP, increased TOM5 was in line with lung fibrosis. In vitro, TOM5 regulated the mitochondrial membrane potential in alveolar epithelial cells. TOM5 reduced the proportion of early apoptotic cells and promoted cell proliferation. Our study shed light on the roles of TOM5 in OP.
Topics: Animals; Alveolar Epithelial Cells; Mice; Humans; Membrane Potential, Mitochondrial; Mitochondrial Precursor Protein Import Complex Proteins; Male; Apoptosis; Female; Cell Proliferation; Mice, Inbred C57BL; Disease Models, Animal; Cryptogenic Organizing Pneumonia; Organizing Pneumonia
PubMed: 38794801
DOI: 10.1080/13510002.2024.2354625 -
Cancers May 2024Non-Hispanic Black breast cancer survivors have poorer outcomes and higher mortality rates than White survivors, but systemic biological mechanisms underlying these...
Non-Hispanic Black breast cancer survivors have poorer outcomes and higher mortality rates than White survivors, but systemic biological mechanisms underlying these disparities are unclear. We used circulating leukocytes as a surrogate for measuring systemic mechanisms, which might be different from processes in the target tissue (e.g., breast). We investigated race-based differences in DNA damage and repair, using a novel CometChip assay, in circulating leukocytes from breast cancer survivors who had completed primary cancer therapy and were cancer free. We observed novel race-based differences in systemic DNA damage and repair activity in cancer survivors, but not in cells from healthy volunteers. Basal DNA damage in leukocytes was higher in White survivors, but Black survivors showed a much higher induction after bleomycin treatment. Double-strand break repair activity was also significantly different between the races, with cells from White survivors showing more sustained repair activity compared to Black leukocytes. These results suggest that cancer and cancer therapy might have long-lasting effects on systemic DNA damage and repair mechanisms that differ in White survivors and Black survivors. Findings from our preliminary study in non-cancer cells (circulating leukocytes) suggest systemic effects beyond the target site, with implications for accelerated aging-related cancer survivorship disparities.
PubMed: 38791886
DOI: 10.3390/cancers16101807 -
International Journal of Molecular... May 2024We previously found IQ motif containing GTPase activating protein (IQGAP1) to be consistently elevated in lung fibroblasts (LF) isolated from patients with scleroderma...
We previously found IQ motif containing GTPase activating protein (IQGAP1) to be consistently elevated in lung fibroblasts (LF) isolated from patients with scleroderma (systemic sclerosis, SSc)-associated interstitial lung disease (ILD) and reported that IQGAP1 contributed to SSc by regulating expression and organization of α-smooth muscle actin (SMA) in LF. The aim of this study was to compare the development of ILD in the presence and absence of IQGAP1. Pulmonary fibrosis was induced in IQGAP1 knockout (KO) and wild-type (WT) mice by a single-intratracheal instillation of bleomycin. Two and three weeks later, mice were euthanized and investigated. We observed that the IQGAP1 KO mouse was characterized by a reduced rate of actin polymerization with reduced accumulation of actin in the lung compared to the WT mouse. After exposure to bleomycin, the IQGAP1 KO mouse demonstrated decreased contractile activity of LF, reduced expression of SMA, TGFβ, and collagen, and lowered overall fibrosis scores compared to the WT mouse. The numbers of inflammatory cells and expression of pro-inflammatory cytokines in lung tissue were not significantly different between IQGAP1 KO and WT mice. We conclude that IQGAP1 plays an important role in the development of lung fibrosis induced by bleomycin, and the absence of IQGAP1 reduces the contractile activity of lung fibroblast and bleomycin-induced pulmonary fibrosis. Thus, IQGAP1 may be a potential target for novel anti-fibrotic therapies for lung fibrosis.
Topics: Animals; Bleomycin; ras GTPase-Activating Proteins; Actins; Pulmonary Fibrosis; Mice; Mice, Knockout; Fibroblasts; Lung; Mice, Inbred C57BL; Polymerization; Disease Models, Animal
PubMed: 38791282
DOI: 10.3390/ijms25105244 -
Molecular Medicine (Cambridge, Mass.) May 2024The development of pulmonary fibrosis involves a cascade of events, in which inflammation mediated by immune cells plays a pivotal role. Chemotherapeutic drugs have been...
BACKGROUND
The development of pulmonary fibrosis involves a cascade of events, in which inflammation mediated by immune cells plays a pivotal role. Chemotherapeutic drugs have been shown to have dual effects on fibrosis, with bleomycin exacerbating pulmonary fibrosis and bortezomib alleviating tissue fibrotic processes. Understanding the intricate interplay between chemotherapeutic drugs, immune responses, and pulmonary fibrosis is likely to serve as the foundation for crafting tailored therapeutic strategies.
METHODS
A model of bleomycin-induced pulmonary fibrosis was established, followed by treatment with bortezomib. Tissue samples were collected for analysis of immune cell subsets and functional assessment by flow cytometry and in vitro cell experiments. Additionally, multi-omics analysis was conducted to further elucidate the expression of chemokines and chemokine receptors, as well as the characteristics of cell populations.
RESULTS
Here, we observed that the expression of CXCL16 and CXCR6 was elevated in the lung tissue of a pulmonary fibrosis model. In the context of pulmonary fibrosis or TGF-β1 stimulation in vitro, macrophages exhibited an M2-polarized phenotype and secreted more CXCL16 than those of the control group. Moreover, flow cytometry revealed increased expression levels of CD69 and CXCR6 in pulmonary CD4 T cells during fibrosis progression. The administration of bortezomib alleviated bleomycin-induced pulmonary fibrosis, accompanied by reduced ratio of M2-polarized macrophages and decreased accumulation of CD4 T cells expressing CXCR6.
CONCLUSIONS
Our findings provide insights into the key immune players involved in bleomycin-induced pulmonary fibrosis and offer preclinical evidence supporting the repurposing strategy and combination approaches to reduce lung fibrosis.
Topics: Bleomycin; Bortezomib; Pulmonary Fibrosis; Animals; Mice; Receptors, CXCR6; Chemokine CXCL16; CD4-Positive T-Lymphocytes; Disease Models, Animal; Macrophages; Male; Mice, Inbred C57BL; Chemotaxis; Antigens, Differentiation, T-Lymphocyte; Antigens, CD; Lectins, C-Type
PubMed: 38789926
DOI: 10.1186/s10020-024-00836-5 -
The American Journal of Pathology May 2024Idiopathic pulmonary fibrosis, a fatal interstitial lung disease, is characterized by fibroblast activation and aberrant extracellular matrix accumulation. Effective...
Idiopathic pulmonary fibrosis, a fatal interstitial lung disease, is characterized by fibroblast activation and aberrant extracellular matrix accumulation. Effective therapeutic development is limited because of incomplete understanding of the mechanisms by which fibroblasts become aberrantly activated. Here, we show acetaldehyde dehydrogenase 2 (ALDH2) in fibroblasts as a potential therapeutic target for pulmonary fibrosis. A decrease in ALDH2 expression was observed in patients with idiopathic pulmonary fibrosis and bleomycin-treated mice. ALDH2 deficiency spontaneously induces collagen accumulation in the lungs of aged mice. Furthermore, young ALDH2 knockout mice exhibited exacerbated bleomycin-induced pulmonary fibrosis and increased mortality compared with that in control mice. Mechanistic studies revealed that transforming growth factor (TGF)-β1 induction and ALDH2 depletion constitute a positive feedback loop that exacerbates fibroblast activation. TGF-β1 down-regulated ALDH2 through a TGF-β receptor 1/Smad3-dependent mechanism. The subsequent deficiency in ALDH2 resulted in fibroblast dysfunction that manifested as impaired mitochondrial autophagy and senescence, leading to fibroblast activation and extracellular matrix production. ALDH2 overexpression markedly suppressed fibroblast activation, and this effect was abrogated by PTEN-induced putative kinase 1 (PINK1) knockdown, indicating that the profibrotic effects of ALDH2 are PINK1- dependent. Furthermore, Alda-1-induced ALDH2 activation reversed the established pulmonary fibrosis in both young and aged mice. In conclusion, ALDH2 expression inhibits the pathogenesis of pulmonary fibrosis. Strategies to up-regulate or activate ALDH2 expression could be potential therapies for pulmonary fibrosis.
PubMed: 38777148
DOI: 10.1016/j.ajpath.2024.04.008 -
PloS One 2024The transmembrane protein Agp2, initially shown as a transporter of L-carnitine, mediates the high-affinity transport of polyamines and the anticancer drug bleomycin-A5....
The transmembrane protein Agp2, initially shown as a transporter of L-carnitine, mediates the high-affinity transport of polyamines and the anticancer drug bleomycin-A5. Cells lacking Agp2 are hyper-resistant to polyamine and bleomycin-A5. In these earlier studies, we showed that the protein synthesis inhibitor cycloheximide blocked the uptake of bleomycin-A5 into the cells suggesting that the drug uptake system may require de novo synthesis. However, our recent findings demonstrated that cycloheximide, instead, induced rapid degradation of Agp2, and in the absence of Agp2 cells are resistant to cycloheximide. These observations raised the possibility that the degradation of Agp2 may allow the cell to alter its drug resistance network to combat the toxic effects of cycloheximide. In this study, we show that membrane extracts from agp2Δ mutants accentuated several proteins that were differentially expressed in comparison to the parent. Mass spectrometry analysis of the membrane extracts uncovered the pleiotropic drug efflux pump, Pdr5, involved in the efflux of cycloheximide, as a key protein upregulated in the agp2Δ mutant. Moreover, a global gene expression analysis revealed that 322 genes were differentially affected in the agp2Δ mutant versus the parent, including the prominent PDR5 gene and genes required for mitochondrial function. We further show that Agp2 is associated with the upstream region of the PDR5 gene, leading to the hypothesis that cycloheximide resistance displayed by the agp2Δ mutant is due to the derepression of the PDR5 gene.
Topics: Cycloheximide; Protein Synthesis Inhibitors; Saccharomyces cerevisiae Proteins; ATP-Binding Cassette Transporters; Saccharomyces cerevisiae; Up-Regulation; Drug Resistance, Fungal; Gene Expression Regulation, Fungal
PubMed: 38776347
DOI: 10.1371/journal.pone.0303747 -
Heliyon May 2024The objective of this study was to provide theoretically feasible strategies by understanding the relationship between the immune microenvironment and the diagnosis and...
PURPOSE
The objective of this study was to provide theoretically feasible strategies by understanding the relationship between the immune microenvironment and the diagnosis and prognosis of AML patients. To this end, we built a ceRNA network with lncRNAs as the core and analyzed the related lncRNAs in the immune microenvironment by bioinformatics analysis.
METHODS
AML transcriptome expression data and immune-related gene sets were obtained from TCGA and ImmPort. Utilizing Pearson correlation analysis, differentially expressed immune-related lncRNAs were identified. Then, the LASSO-Cox regression analysis was performed to generate a risk signature consisting immune-related lncRNAs. Accuracy of signature in predicting patient survival was evaluated using univariate and multivariate analysis. Next, GO and KEGG gene enrichment and ssGSEA were carried out for pathway enrichment analysis of 183 differentially expressed genes, followed by drug sensitivity and immune infiltration analysis with pRRophetic and CIBERSORT, respectively. Cytoscape was used to construct the ceRNA network for these lncRNAs.
RESULTS
816 common lncRNAs were selected to acquire the components related to prognosis. The final risk signature established by multivariate Cox and stepwise regression analysis contained 12 lncRNAs engaged in tumor apoptotic and metastatic processes: LINC02595, HCP5, AC020934.2, AC008770.3, LINC01770, AC092718.4, AL589863.1, AC131097.4, AC012368.1, C1RL-AS1, STARD4-AS1, and AC243960.1. Based on this predictive model, high-risk patients exhibited lower overall survival rates than low-risk patients. Signature lncRNAs showed significant correlation with tumor-infiltrating immune cells. In addition, significant differences in PD-1/PD-L1 expression and bleomycin/paclitaxel sensitivity were observed between risk groups.
CONCLUSION
LncRNAs related to immune microenvironment were prospective prognostic and therapeutic options for AML.
PubMed: 38774083
DOI: 10.1016/j.heliyon.2024.e30616 -
Theranostics 2024Idiopathic pulmonary fibrosis (IPF) is an irreversible, fatal interstitial lung disease lacking specific therapeutics. Nicotinamide phosphoribosyltransferase (NAMPT),...
Idiopathic pulmonary fibrosis (IPF) is an irreversible, fatal interstitial lung disease lacking specific therapeutics. Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme of the nicotinamide adenine dinucleotide (NAD) salvage biosynthesis pathway and a cytokine, has been previously reported as a biomarker for lung diseases; however, the role of NAMPT in pulmonary fibrosis has not been elucidated. We identified the NAMPT level changes in pulmonary fibrosis by analyzing public RNA-Seq databases, verified in collected clinical samples and mice pulmonary fibrosis model by Western blotting, qRT-PCR, ELISA and Immunohistochemical staining. We investigated the role and mechanism of NAMPT in lung fibrosis by using pharmacological inhibition on NAMPT and transgenic mice. macrophage depletion by clodronate liposomes and reinfusion of IL-4-induced M2 bone marrow-derived macrophages (BMDMs) from wild-type mice, combined with cell experiments, were performed to further validate the mechanism underlying NAMPT involving lung fibrosis. We found that NAMPT increased in the lungs of patients with IPF and mice with bleomycin (BLM)-induced pulmonary fibrosis. NAMPT inhibitor FK866 alleviated BLM-induced pulmonary fibrosis in mice and significantly reduced NAMPT levels in bronchoalveolar lavage fluid (BALF). The lung single-cell RNA sequencing showed that NAMPT expression in monocytes/macrophages of IPF patients was much higher than in other lung cells. Knocking out NAMPT in mouse monocytes/macrophages () significantly alleviated BLM-induced pulmonary fibrosis in mice, decreased NAMPT levels in BALF, reduced the infiltration of M2 macrophages in the lungs and improved mice survival. Depleting monocytes/macrophages in mice by clodronate liposomes and subsequent pulmonary reinfusion of IL-4-induced M2 BMDMs from wild-type mice, reversed the protective effect of monocyte/macrophage NAMPT-deletion on lung fibrosis. experiments confirmed that the mechanism of NAMPT engaged in pulmonary fibrosis is related to the released NAMPT by macrophages promoting M2 polarization in a non-enzyme-dependent manner by activating the STAT6 signal pathway. NAMPT prompts bleomycin-induced pulmonary fibrosis by driving macrophage M2 polarization in mice. Targeting the NAMPT of monocytes/macrophages is a promising strategy for treating pulmonary fibrosis.
Topics: Animals; Nicotinamide Phosphoribosyltransferase; Bleomycin; Mice; Macrophages; Idiopathic Pulmonary Fibrosis; Cytokines; Humans; Mice, Inbred C57BL; Disease Models, Animal; Lung; Pulmonary Fibrosis; Mice, Transgenic; Male; Piperidines; Female; Acrylamides
PubMed: 38773984
DOI: 10.7150/thno.94482 -
Theranostics 2024Pulmonary fibrosis is a chronic progressive lung disease with limited therapeutic options. We previously revealed that there is iron deposition in alveolar epithelial...
Pulmonary fibrosis is a chronic progressive lung disease with limited therapeutic options. We previously revealed that there is iron deposition in alveolar epithelial type II cell (AECII) in pulmonary fibrosis, which can be prevented by the iron chelator deferoxamine. However, iron in the cytoplasm and the mitochondria has two relatively independent roles and regulatory systems. In this study, we aimed to investigate the role of mitochondrial iron deposition in AECII injury and pulmonary fibrosis, and to find potential therapeutic strategies. BLM-treated mice, MLE-12 cells, and primary AECII were employed to establish the mouse pulmonary fibrosis model and epithelial cells injury model, respectively. Mitochondrial transplantation, siRNA and plasmid transfection, western blotting (WB), quantitative real-time polymerase chain reaction (RT-qPCR), polymerase chain reaction (PCR), immunofluorescence, immunoprecipitation (IP), MitoSOX staining, JC-1 staining, oxygen consumption rate (OCR) measurement, and Cell Counting Kit-8 (CCK8) assay were utilized to elucidate the role of mitochondrial iron deposition in cell and lung fibrosis and determine its mechanism. This study showed that prominent mitochondrial iron deposition occurs within AECII in bleomycin (BLM)-induced pulmonary fibrosis mouse model and in BLM-treated MLE-12 epithelial cells. Further, the study revealed that healthy mitochondria rescue BLM-damaged AECII mitochondrial iron deposition and cell damage loss. Mitoferrin-2 (MFRN2) is the main transporter that regulates mitochondrial iron metabolism by transferring cytosolic iron into mitochondria, which is upregulated in BLM-treated MLE-12 epithelial cells. Direct overexpression of MFRN2 causes mitochondrial iron deposition and cell damage. In this study, decreased ubiquitination of the ubiquitin ligase F-box/LRR-repeat protein 5 (FBXL5) degraded iron-reactive element-binding protein 2 (IREB2) and promoted MFRN2 expression as well as mitochondrial iron deposition in damaged AECII. Activation of the prostaglandin E2 receptor EP4 subtype (EP4) receptor signaling pathway counteracted mitochondrial iron deposition by downregulating IREB2-MFRN2 signaling through upregulation of FBXL5. This intervention not only reduced mitochondrial iron content but also preserved mitochondrial function and protected against AECII damage after BLM treatment. Our findings highlight the unexplored roles, mechanisms, and regulatory approaches of abnormal mitochondrial iron metabolism of AECII in pulmonary fibrosis. Therefore, this study deepens the understanding of the mechanisms underlying pulmonary fibrosis and offers a promising strategy for developing effective therapeutic interventions using the EP4 receptor activator.
Topics: Animals; Bleomycin; Mitochondria; Pulmonary Fibrosis; Mice; Iron; Alveolar Epithelial Cells; Disease Models, Animal; Mice, Inbred C57BL; Cell Line; Male
PubMed: 38773980
DOI: 10.7150/thno.94072