AAV1.SERCA2a Gene Therapy Reverses Pulmonary Fibrosis by Blocking the STAT3/FOXM1 Pathway and Promoting the SNON/SKI Axis

Bioinformatics and systems-biology approach to identify common pathogenic mechanisms for COVID-19 and systemic lupus erythematosus

BACKGROUND

The Coronavirus disease 2019 (COVID-19) pandemic has brought a heavy burden to the world, interestingly, it shares many clinical symptoms with systemic lupus erythematosus (SLE). It is unclear whether there is a similar pathological process between COVID-9 and SLE. In addition, we don't know how to treat SLE patients with COVID-19. In this study, we analyse the potential similar pathogenesis between SLE and COVID-19 and explore their possible drug regimens using bioinformatics and systems biology approaches.

METHODS

The common differentially expressed genes (DEGs) were extracted from the COVID-19 datasets and the SLE datasets for functional enrichment, pathway analysis and candidate drug analysis.

RESULT

Based on the two transcriptome datasets between COVID-19 and SLE, 325 common DEGs were selected. Hub genes were identified by protein-protein interaction (PPI) analysis. few found a variety of similar functional changes between COVID-19 and SLE, which may be related to the pathogenesis of COVID-19. Besides, we explored the related regulatory networks. Then, through drug target matching, we found many candidate drugs for patients with COVID-19 only or COVID-19 combined with SLE.

CONCLUSION

COVID-19 and SLE patients share many common hub genes, related pathways and regulatory networks. Based on these common targets, we found many potential drugs that could be used in treating patient with COVID-19 or COVID-19 combined with SLE.

Mechanistic insights into the treatment of pulmonary fibrosis with bioactive components from traditional chinese medicine via matrix stiffness-mediated EMT

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease with limited therapeutic options. Our previous research has shown that the Jinshui Huanxian formula (JHF) is effective in treating IPF. However, the biomechanical mechanisms of its refined components, known as the effective-component compatibility of JHF II (ECC-JHF II), are not well understood.

PURPOSE

This study aims to explore how bioactive components from traditional Chinese medicine (TCM) impact the biomechanical progression of pulmonary fibrosis.

STUDY DESIGN AND METHODS

A mouse model of pulmonary fibrosis was established by a single intratracheal instillation of bleomycin (Bleomycin). Pulmonary function, pathological changes, collagen deposition, lung tissue stiffness, and EMT markers were evaluated at the end of the study. Polyethylene glycol hydrogels with adjustable stiffness were used to mimic both normal and pathological lung conditions. The effects of ECC-JHF II on matrix stiffness-mediated EMT were assessed by quantitative real-time PCR, western blot, and immunofluorescence. The biomechanical mechanisms underlying ECC-JHF II on EMT and pulmonary fibrosis were verified both in vivo and in vitro.

RESULTS

ECC-JHF II significantly improved bleomycin (Bleomycin)-induced pulmonary fibrosis in mice, manifested as increased tidal volume and 50 % tidal volume expiratory flow, reduced lung tissue stiffness, and decreased EMT markers. Histopathological analysis showed reduced inflammation, alveolar damage, and collagen deposition. In vitro, ECC-JHF II reversed the EMT phenotypic transition induced by substrate stiffness, demonstrated by the upregulation of E-cadherin, occludin, and zonula occluden-1, and the downregulation of N-cadherin, vimentin, caldesmon 1 and tropomyosin 1. Moreover, ECC-JHF II could inhibit integrin/ROCK/MRTF signaling in vitro and in vivo. Silencing integrin β1 or activating it with pyrintegrin further confirmed the role of integrin β1 in the mechanotransduction pathway and the efficacy of ECC-JHF II.

CONCLUSION

Taken together, the findings of this study indicate that ECC-JHF II exerts a therapeutic effect on pulmonary fibrosis through the attenuation of lung tissue stiffness and inhibition of EMT, potentially via the integrin/ROCK/MRTF signaling pathway.

Type I collagen-targeted liposome delivery of Serca2a modulates myocardium calcium homeostasis and reduces cardiac fibrosis induced by myocardial infarction

Fibrotic scarring and impaired myocardial calcium homeostasis serve as the two main factors in the pathology of heart failure following myocardial infarction (MI), leading to poor prognosis and death in patients. Serca2a is a target of interest in gene therapy for MI-induced heart failure via the regulation of intracellular calcium homeostasis and, subsequently, enhancing myocardial contractility. A recent study also reported that Serca2a ameliorates pulmonary fibrosis by blocking nuclear factor kB (NF-kB)/interleukin-6 (IL-6)-induced (SMAD)/TGF-β signaling activation, while the effect in MI-induced myocardial fibrosis remains to be addressed. Here, we loaded Serca2a plasmids into type 1 collagen-targeting nanoparticles to synthesize the GKWHCTTKFPHHYCLY-Serca2a-Liposome (GSL-NPs) for targeted treatment of myocardial infarction. We showed that GSL-NPs were effectively targeted in the scar area in MI-induced mice within tail-vein delivery for 48 h. Treatment with GSL-NPs improved cardiac functions and shrank fibrotic scars after MI in mice by up-regulating Serca2a. In cardiac fibroblasts, GSL-NPs alleviated hypoxia-induced fibrotic progression partly by inhibiting NF-kB activation. Furthermore, treatment with GSL-NPs protected cardiomyocyte calcium homeostasis and enhanced myocardial contractility during hypoxia. Together, we demonstrate that type I collagen-targeted liposome delivery of Serca2a may benefit patients with myocardial infarction by inhibiting fibrotic scarring as well as modulation of calcium homeostasis.

Role of FOXM1 and AURKB in regulating keratinocyte function in psoriasis

Objective

This study investigated the effect of forkhead box M1 (FOXM1) and Aurora kinase B (AURKB) on the epidermal function of keratinocytes.

Methods

Bioinformatics analysis was used to analyze the co-expression network of FOXM1 and its correlation with AURKB. The expression of FOXM1 and AURKB in tissues and cells was detected by immunofluorescence and real-time quantitative polymerase chain reaction, respectively. HaCaT cells were transfected with si-FOXM1 to knock down FOXM1. Cell proliferation was detected by cell counting kit-8 assay. Cell migration was detected by scratch assay. Cell invasion was detected by the Transwell invasion assay. Cell apoptosis and cell cycle were detected by flow cytometry.

Results

FOXM1 and AURKB were positively correlated and highly expressed in psoriatic lesions. After transfection of si-FOXM1, the expression levels of FOXM1 and AURKB genes significantly decreased. The proliferation of HaCaT cells decreased, the apoptosis rate increased significantly, and the proportion of cells in the G1 phase increased significantly, while the proportion of cells in the S phase decreased significantly. The scratch closure of HaCaT cells was reduced, and the number of cell invasions decreased significantly.

Conclusion

FOXM1 and AURKB may affect the progression of psoriasis by regulating the proliferation, cell cycle, migration, and invasion of keratinocytes.

Pharmacological Inhibition of Epac1 Protects against Pulmonary Fibrosis by Blocking FoxO3a Neddylation

Background

Idiopathic Pulmonary fibrosis (IPF) is characterized by progressive scarring and fibrosis within the lungs. There is currently no cure for IPF; therefore, there is an urgent need to identify novel therapeutic targets that can prevent the progression of IPF. Compelling evidence indicates that the second messenger, cyclic adenosine monophosphate (cAMP), inhibits lung fibroblast proliferation and differentiation through the classical PKA pathway. However, the contribution of the e xchange p rotein directly a ctivated by c AMP 1 (Epac1) to IPF pathophysiological processes is yet to be investigated.

Objective

To determine the role of the cAMP-binding protein Epac1 in the progression of IPF.

Methods

We used lung samples from IPF patients or healthy controls, mouse lung samples, or lung fibroblast isolated from a preclinical mouse model of PF induced by bleomycin intratracheal injection. The effect of bleomycin (BLM) treatment was determined in Epac1 knock-out mice or wild-type littermates. Epac1 expression was modulated in vitro by using lentiviral vectors or adenoviruses. The therapeutic potential of the Epac1-selective pharmacological inhibitor, AM-001, was tested in vivo and in vitro, using a bleomycin mouse model of PF and an ex vivo precision-cut lung slices (PCLs) model of human lung fibrosis.

Results

Epac1 expression was increased in the lung tissue of IPF patients, in IPF-diseased fibroblasts and in BLM-challenged mice. Furthermore, Epac1 genetic or pharmacological inhibition with AM-001 decreased normal and IPF fibroblast proliferation and the expression of profibrotic markers, αSMA, TGF-β/SMAD2/3, and interleukin-6 (IL-6)/STAT3 signaling pathways. Consistently, blocking Epac1 protected against BLM-induced lung injury and fibrosis, suggesting a therapeutic effect of Epac1 inhibition on PF pathogenesis and progression. Global gene expression profiling revealed a decrease in the key components of the profibrotic gene signature and neddylation pathway in Epac1-deficient lung fibroblasts and IPF human-derived PLCs. Mechanistically, the protective effect of Epac1 inhibition against PF development involves the inhibition of FoxO3a neddylation and its subsequent degradation by NEDD8, and in part, by limiting the proliferative capacity of lung-infiltrating monocytes.

Conclusions

We demonstrated that Epac1 is an important regulator of the pathological state of fibroblasts in PF and that small molecules targeting Epac1 can serve as novel therapeutic drugs against PF.

RNA-sequencing reveals differential fibroblast responses to bleomycin and pneumonectomy

Pulmonary fibrosis is characterized by pathological accumulation of scar tissue in the lung parenchyma. Many of the processes that are implicated in fibrosis, including increased extracellular matrix synthesis, also occur following pneumonectomy (PNX), but PNX instead results in regenerative compensatory growth of the lung. As fibroblasts are the major cell type responsible for extracellular matrix production, we hypothesized that comparing fibroblast responses to PNX and bleomycin (BLM) would unveil key differences in the role they play during regenerative versus fibrotic lung responses. RNA-sequencing was performed on flow-sorted fibroblasts freshly isolated from mouse lungs 14 days after BLM, PNX, or sham controls. RNA-sequencing analysis revealed highly similar biological processes to be involved in fibroblast responses to both BLM and PNX, including TGF-β1 and TNF-α. Interestingly, we observed smaller changes in gene expression after PNX than BLM at Day 14, suggesting that the fibroblast response to PNX may be muted by expression of transcripts that moderate pro-fibrotic pathways. Itpkc, encoding inositol triphosphate kinase C, was a gene uniquely up-regulated by PNX and not BLM. ITPKC overexpression in lung fibroblasts antagonized the pro-fibrotic effect of TGF-β1. RNA-sequencing analysis has identified considerable overlap in transcriptional changes between fibroblasts following PNX and those overexpressing ITPKC.

The Interaction of OTUB1 and TRAF3 Mediates NLRP3 Inflammasome Activity to Regulate TGF-β1-induced BEAS-2B Cell Injury

Asthma is a frequently chronic respiratory disease with inflammation and remodeling in the airway. OTUB1 has been reported to be associated with pulmonary diseases. However, the role and potential mechanism of OTUB1 in asthma remain unclear. The expressions of OTUB1 in the bronchial mucosal tissues of asthmatic children and TGF-β1-induced BEAS-2B cells were determined. The biological behaviors were assessed in an asthma in vitro model using a loss-function approach. The contents of inflammatory cytokines were detected by ELISA kits. The related protein expressions were performed using western blot assay. Besides, the interaction between OTUB1 and TRAF3 was detected by Co-IP and ubiquitination assays. Our results showed that OTUB1 level was increased in asthmatic bronchial mucosal tissues and TGF-β1-induced BEAS-2B cells. OTUB1 knockdown promoted proliferation, inhibited apoptosis and EMT of TGF-β1-treated cells. The inhibition of OTUB1 attenuated the TGF-β1-induced inflammation and remodeling. Furthermore, OTUB1 knockdown inhibited the deubiquitination of TRAF3 and further suppressed the activation of NLRP3 inflammasome. The overexpression of TRAF3 or NLRP3 reversed the positive role of OTUB1 knockdown in TGF-β1-induced cells injury. Collectively, OTUB1 deubiquitinates TRAF3 to activate NLRP3 inflammasome, thereby leading to inflammation and remodeling of TGF-β1-induced cells, and further promoting the pathogenesis of asthma.

Pulmonary vascular fibrosis in pulmonary hypertension - The role of the extracellular matrix as a therapeutic target

Pulmonary hypertension (PH) is a condition characterized by changes in the extracellular matrix (ECM) deposition and vascular remodeling of distal pulmonary arteries. These changes result in increased vessel wall thickness and lumen occlusion, leading to a loss of elasticity and vessel stiffening. Clinically, the mechanobiology of the pulmonary vasculature is becoming increasingly recognized for its prognostic and diagnostic value in PH. Specifically, the increased vascular fibrosis and stiffening resulting from ECM accumulation and crosslinking may be a promising target for the development of anti- or reverse-remodeling therapies. Indeed, there is a huge potential in therapeutic interference with mechano-associated pathways in vascular fibrosis and stiffening. The most direct approach is aiming to restore extracellular matrix homeostasis, by interference with its production, deposition, modification and turnover. Besides structural cells, immune cells contribute to the level of ECM maturation and degradation by direct cell-cell contact or the release of mediators and proteases, thereby opening a huge avenue to target vascular fibrosis via immunomodulation approaches. Indirectly, intracellular pathways associated with altered mechanobiology, ECM production, and fibrosis, offer a third option for therapeutic intervention. In PH, a vicious cycle of persistent activation of mechanosensing pathways such as YAP/TAZ initiates and perpetuates vascular stiffening, and is linked to key pathways disturbed in PH, such as TGF-beta/BMPR2/STAT. Together, this complexity of the regulation of vascular fibrosis and stiffening in PH allows the exploration of numerous potential therapeutic interventions. This review discusses connections and turning points of several of these interventions in detail.

FOXM1: Functional Roles of FOXM1 in Non-Malignant Diseases

Forkhead box (FOX) proteins are a wing-like helix family of transcription factors in the DNA-binding region. By mediating the activation and inhibition of transcription and interactions with all kinds of transcriptional co-regulators (MuvB complexes, STAT3, β-catenin, etc.), they play significant roles in carbohydrate and fat metabolism, biological aging and immune regulation, development, and diseases in mammals. Recent studies have focused on translating these essential findings into clinical applications in order to improve quality of life, investigating areas such as diabetes, inflammation, and pulmonary fibrosis, and increase human lifespan. Early studies have shown that forkhead box M1 (FOXM1) functions as a key gene in pathological processes in multiple diseases by regulating genes related to proliferation, the cell cycle, migration, and apoptosis and genes related to diagnosis, therapy, and injury repair. Although FOXM1 has long been studied in relation to human diseases, its role needs to be elaborated on. FOXM1 expression is involved in the development or repair of multiple diseases, including pulmonary fibrosis, pneumonia, diabetes, liver injury repair, adrenal lesions, vascular diseases, brain diseases, arthritis, myasthenia gravis, and psoriasis. The complex mechanisms involve multiple signaling pathways, such as WNT/β-catenin, STAT3/FOXM1/GLUT1, c-Myc/FOXM1, FOXM1/SIRT4/NF-κB, and FOXM1/SEMA3C/NRP2/Hedgehog. This paper reviews the key roles and functions of FOXM1 in kidney, vascular, lung, brain, bone, heart, skin, and blood vessel diseases to elucidate the role of FOXM1 in the development and progression of human non-malignant diseases and makes suggestions for further research.

OTUB1 promotes osteoblastic bone formation through stabilizing FGFR2

Bone homeostasis is maintained by the balance between osteoblastic bone formation and osteoclastic bone resorption. Dysregulation of this process leads to multiple diseases, including osteoporosis. However, the underlying molecular mechanisms are not fully understood. Here, we show that the global and conditional osteoblast knockout of a deubiquitinase Otub1 result in low bone mass and poor bone strength due to defects in osteogenic differentiation and mineralization. Mechanistically, the stability of FGFR2, a crucial regulator of osteogenesis, is maintained by OTUB1. OTUB1 attenuates the E3 ligase SMURF1-mediated FGFR2 ubiquitination by inhibiting SMURF1's E2 binding. In the absence of OTUB1, FGFR2 is ubiquitinated excessively by SMURF1, followed by lysosomal degradation. Consistently, adeno-associated virus serotype 9 (AAV9)-delivered FGFR2 in knee joints rescued the bone mass loss in osteoblast-specific Otub1-deleted mice. Moreover, Otub1 mRNA level was significantly downregulated in bones from osteoporotic mice, and restoring OTUB1 levels through an AAV9-delivered system in ovariectomy-induced osteoporotic mice attenuated osteopenia. Taken together, our results suggest that OTUB1 positively regulates osteogenic differentiation and mineralization in bone homeostasis by controlling FGFR2 stability, which provides an optical therapeutic strategy to alleviate osteoporosis.

Wilms Tumor 1-Driven Fibroblast Activation and Subpleural Thickening in Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease that is often fatal due to the formation of irreversible scar tissue in the distal areas of the lung. Although the pathological and radiological features of IPF lungs are well defined, the lack of insight into the fibrogenic role of fibroblasts that accumulate in distinct anatomical regions of the lungs is a critical knowledge gap. Fibrotic lesions have been shown to originate in the subpleural areas and extend into the lung parenchyma through processes of dysregulated fibroproliferation, migration, fibroblast-to-myofibroblast transformation, and extracellular matrix production. Identifying the molecular targets underlying subpleural thickening at the early and late stages of fibrosis could facilitate the development of new therapies to attenuate fibroblast activation and improve the survival of patients with IPF. Here, we discuss the key cellular and molecular events that contribute to (myo)fibroblast activation and subpleural thickening in IPF. In particular, we highlight the transcriptional programs involved in mesothelial to mesenchymal transformation and fibroblast dysfunction that can be targeted to alter the course of the progressive expansion of fibrotic lesions in the distal areas of IPF lungs.

Genes in pediatric pulmonary arterial hypertension and the most promising BMPR2 gene therapy

Pulmonary arterial hypertension (PAH) is a rare but progressive and lethal vascular disease of diverse etiologies, mainly caused by proliferation of endothelial cells, smooth muscle cells in the pulmonary artery, and fibroblasts, which ultimately leads to right-heart hypertrophy and cardiac failure. Recent genetic studies of childhood-onset PAH report that there is a greater genetic burden in children than in adults. Since the first-identified pathogenic gene of PAH, BMPR2, which encodes bone morphogenetic protein receptor 2, a receptor in the transforming growth factor-β superfamily, was discovered, novel causal genes have been identified and substantially sharpened our insights into the molecular genetics of childhood-onset PAH. Currently, some newly identified deleterious genetic variants in additional genes implicated in childhood-onset PAH, such as potassium channels (KCNK3) and transcription factors (TBX4 and SOX17), have been reported and have greatly updated our understanding of the disease mechanism. In this review, we summarized and discussed the advances of genetic variants underlying childhood-onset PAH susceptibility and potential mechanism, and the most promising BMPR2 gene therapy and gene delivery approaches to treat childhood-onset PAH in the future.

Progress in Respiratory Gene Therapy

The prospect of gene therapy for inherited and acquired respiratory disease has energized the research community since the 1980s, with cystic fibrosis, as a monogenic disorder, driving early efforts to develop effective strategies. The fact that there are still no approved gene therapy products for the lung, despite many early phase clinical trials, illustrates the scale of the challenge: In the 1990s, first-generation non-viral and viral vector systems demonstrated proof-of-concept but low efficacy. Since then, there has been steady progress toward improved vectors with the capacity to overcome at least some of the formidable barriers presented by the lung. In addition, the inclusion of features such as codon optimization and promoters providing long-term expression have improved the expression characteristics of therapeutic transgenes. Early approaches were based on gene addition, where a new DNA copy of a gene is introduced to complement a genetic mutation: however, the advent of RNA-based products that can directly express a therapeutic protein or manipulate gene expression, together with the expanding range of tools for gene editing, has stimulated the development of alternative approaches. This review discusses the range of vector systems being evaluated for lung delivery; the variety of cargoes they deliver, including DNA, antisense oligonucleotides, messenger RNA (mRNA), small interfering RNA (siRNA), and peptide nucleic acids; and exemplifies progress in selected respiratory disease indications.

RNF2 mediates pulmonary fibroblasts activation and proliferation by regulating mTOR and p16-CDK4-Rb1 signaling pathway

BACKGROUND

Pulmonary fibrosis (PF) is a chronic, progressive interstitial lung disease with unknown etiology, associated with increasing morbidity and pessimistic prognosis. Pulmonary fibroblasts (PFbs) are the key effector cells of PF, in which abnormal activation and proliferation is an important pathogenesis of PF. Ring finger protein 2 (RNF2), is identified as the catalytic subunit of poly-comb repressive complex 1, which is closely related to occurrence and development of lung cancer, but its function in PF has not been revealed. In this paper, we sought to identify the regulatory role of RNF2 in lung fibrogenesis and its underlying mechanisms.

METHODS

The expression of RNF2 in lung fibrosis tissue (human and Bleomycin-induced mouse) and cell model (TGF-β1-induced HFL1 cells) was examined by immunoblotting analysis and immunofluorescence. Western blot, qRT-PCR were performed to evaluate the expression of pro-fibrogenic cytokines (including α-SMA, ECM and MMPs/ TIMPs) induced by TGF-β1 in HFL1 cells. Cell proliferation, cycle progression and apoptosis were examined by fow cytometric. Molecular interactions were tested by Co-IP assays.

RESULTS

RNF2 expression was elevated in PF tissues compared to normal adjacent tissues and in PFbs (HFL1) induced by TGF-β1. Furthermore, knockdown of RNF2 could evidently inhibit the abnormal expression of pro-fibrogenic cytokines (including α-SMA, ECM and MMPs/TIMPs) induced by TGF-β1 in HFL1 cells. Functionally, RNF2 silencing could significantly suppress TGF-β1-induced anomalous proliferation, cell cycle progression, apoptosis and autophagy in HFL1 cells. Mechanistically, RNF2 deficiency could effectively inhibit the abnormal activation of mTOR signaling pathway in TGF-β1-induced HFL1 cells, and mTOR pathway had feedback regulation on the expression of RNF2. Further studies RNF2 could regulate the phosphorylation level of RB1 through interacting with p16 to destroy the binding of p16 and CDK4 competitively. Simultaneously, overexpression of RNF2 could show the opposite results.

CONCLUSIONS

These results indicated that RNF2 is a potent pro-fibrogenic molecule for PFbs activation and proliferation through mTOR and p16-CDK4-Rb signaling pathways, and RNF2 inhibition will be a potential therapeutic avenue for treating PF.

Transcriptional regulation of cardiac fibroblast phenotypic plasticity

Cardiac fibroblasts play critical roles in the maintenance of cardiac structure and the response to cardiac insult. Extracellular matrix deposition by activated resident cardiac fibroblasts, called myofibroblasts, is an essential wound healing response. However, persistent fibroblast activation contributes to pathological fibrosis and cardiac chamber stiffening, which can cause diastolic dysfunction, heart failure, and initiate lethal arrhythmias. The dynamic and phenotypically plastic nature of cardiac fibroblasts is governed in part by the transcriptional regulation of genes encoding extracellular matrix molecules. Understanding how fibroblasts integrate various biomechanical cues into a precise transcriptional response may uncover therapeutic strategies to prevent fibrosis. Here, we provide an overview of the recent literature on transcriptional control of cardiac fibroblast plasticity and fibrosis, with a focus on canonical and non-canonical TGF-β signaling, biomechanical regulation of Hippo/YAP and Rho/MRTF signaling, and metabolic and epigenetic control of fibroblast activation.

The Apelin-APJ axis alleviates LPS-induced pulmonary fibrosis and endothelial mesenchymal transformation in mice by promoting Angiotensin-Converting Enzyme 2

Fibrotic alterations resulting from abnormal tissue repair after lung injury are responsible for the high mortality observed after acute respiratory distress syndrome. Therefore, the prevention and treatment of pulmonary fibrosis has been widely concerned. The Apelin-APJ axis plays an important role in the prevention and treatment of respiratory diseases and organ fibrosis. However, its underlying mechanism remains to be further studied. The aim of this study was to investigate whether the anti-pulmonary fibrosis effect of apelin-APJ axis is related to the activation of angiotensin-converting Enzyme 2 (ACE2). Here, we found that exogenous activation of the Apelin-APJ axis alleviates lipopolysaccharide (LPS)-induced pulmonary fibrosis in mice. In vitro studies revealed that Apelin-13 inhibited LPS-induced endothelial mesenchymal transition in lung microvascular endothelial cells, whereas [Ala13]-Apelin-13 (Apelin-APJ axis inhibitor) accelerated LPS-induced endothelial interstitial transformation in lung microvascular endothelial cells. Notably, angiotensin-converting enzyme 2 (ACE2) inhibitor blocks the beneficial effect of the Apelin-APJ axis activation on LPS-induced pulmonary fibrosis. This finding suggests that the Apelin-APJ axis inhibits pulmonary fibrosis by activating ACE2. Simultaneously, accumulating evidence suggests that ubiquitination may contribute to pulmonary fibrosis. Our study found that LPS increased the ubiquitination of ACE2 protein, whereas Apelin-13 inhibited it. In conclusion, exogenous activation of the Apelin-APJ axis improves LPS-induced pulmonary fibrosis in mice and may be a viable therapeutic target for pulmonary fibrosis.

Research on the mechanism of berberine in the treatment of COVID-19 pneumonia pulmonary fibrosis using network pharmacology and molecular docking

Purpose Pulmonary fibrosis caused by COVID-19 pneumonia is a serious complication of COVID-19 infection, there is a lack of effective treatment methods clinically. This article explored the mechanism of action of berberine in the treatment of COVID-19 (Corona Virus Disease 2019, COVID-19) pneumonia pulmonary fibrosis with the help of the network pharmacology and molecular docking. Methods We predicted the role of berberine protein targets with the Pharmmapper database and the 3D structure of berberine in the Pubchem database. And GeneCards database was used in order to search disease target genes and screen common target genes. Then we used STRING web to construct PPI interaction network of common target protein. The common target genes were analyzed by GO and KEGG by DAVID database. The disease-core target gene-drug network was established and molecular docking was used for prediction. We also analyzed the binding free energy and simulates molecular dynamics of complexes. Results Berberine had 250 gene targets, COVID-19 pneumonia pulmonary fibrosis had 191 gene targets, the intersection of which was 23 in common gene targets. Molecular docking showed that berberine was associated with CCl2, IL-6, STAT3 and TNF-α. GO and KEGG analysis reveals that berberine mainly plays a vital role by the signaling pathways of influenza, inflammation and immune response. Conclusion Berberine acts on TNF-α, STAT3, IL-6, CCL2 and other targets to inhibit inflammation and the activation of fibrocytes to achieve the purpose of treating COVID-19 pneumonia pulmonary fibrosis.

Novel Insights into the Therapeutic Potential of Lung-Targeted Gene Transfer in the Most Common Respiratory Diseases

Over the past decades, a better understanding of the genetic and molecular alterations underlying several respiratory diseases has encouraged the development of new therapeutic strategies. Gene therapy offers new therapeutic alternatives for inherited and acquired diseases by delivering exogenous genetic materials into cells or tissues to restore physiological protein expression and/or activity. In this review, we review (1) different types of viral and non-viral vectors as well as gene-editing techniques; and (2) the application of gene therapy for the treatment of respiratory diseases and disorders, including pulmonary arterial hypertension, idiopathic pulmonary fibrosis, cystic fibrosis, asthma, alpha-1 antitrypsin deficiency, chronic obstructive pulmonary disease, non-small-cell lung cancer, and COVID-19. Further, we also provide specific examples of lung-targeted therapies and discuss the major limitations of gene therapy.

Dihydroartemisinin attenuates pulmonary inflammation and fibrosis in rats by suppressing JAK2/STAT3 signaling

Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, has induced a worldwide pandemic since early 2020. COVID-19 causes pulmonary inflammation, secondary pulmonary fibrosis (PF); however, there are still no effective treatments for PF. The present study aimed to explore the inhibitory effect of dihydroartemisinin (DHA) on pulmonary inflammation and PF, and its molecular mechanism. Morphological changes and collagen deposition were analyzed using hematoxylin-eosin staining, Masson staining, and the hydroxyproline content. DHA attenuated early alveolar inflammation and later PF in a bleomycin-induced rat PF model, and inhibited the expression of interleukin (IL)-1β, IL-6, tumor necrosis factor α (TNFα), and chemokine (C-C Motif) Ligand 3 (CCL3) in model rat serum. Further molecular analysis revealed that both pulmonary inflammation and PF were associated with increased transforming growth factor-β1 (TGF-β1), Janus activated kinase 2 (JAK2), and signal transducer and activator 3(STAT3) expression in the lung tissues of model rats. DHA reduced the inflammatory response and PF in the lungs by suppressing TGF-β1, JAK2, phosphorylated (p)-JAK2, STAT3, and p-STAT3. Thus, DHA exerts therapeutic effects against bleomycin-induced pulmonary inflammation and PF by inhibiting JAK2-STAT3 activation. DHA inhibits alveolar inflammation, and attenuates lung injury and fibrosis, possibly representing a therapeutic candidate to treat PF associated with COVID-19.

OTUB1 regulates lung development, adult lung tissue homeostasis, and respiratory control

OTUB1 is one of the most highly expressed deubiquitinases, counter-regulating the two most abundant ubiquitin chain types. OTUB1 expression is linked to the development and progression of lung cancer and idiopathic pulmonary fibrosis in humans. However, the physiological function of OTUB1 is unknown. Here, we show that constitutive whole-body Otub1 deletion in mice leads to perinatal lethality by asphyxiation. Analysis of (single-cell) RNA sequencing and proteome data demonstrated that OTUB1 is expressed in all lung cell types with a particularly high expression during late-stage lung development (E16.5, E18.5). At E18.5, the lungs of animals with Otub1 deletion presented with increased cell proliferation that decreased saccular air space and prevented inhalation. Flow cytometry-based analysis of E18.5 lung tissue revealed that Otub1 deletion increased proliferation of major lung parenchymal and mesenchymal/other non-hematopoietic cell types. Adult mice with conditional whole-body Otub1 deletion (wbOtub1^del/del ) also displayed increased lung cell proliferation in addition to hyperventilation and failure to adapt the respiratory pattern to hypoxia. On the molecular level, Otub1 deletion enhanced mTOR signaling in embryonic and adult lung tissues. Based on these results, we propose that OTUB1 is a negative regulator of mTOR signaling with essential functions for lung cell proliferation, lung development, adult lung tissue homeostasis, and respiratory regulation.

Adenoviral Transduction of Dickkopf-1 Alleviates Silica-Induced Silicosis Development in Lungs of Mice

Silicosis is an occupational disease caused by inhalation of silica dust, which is hallmarked by progressive pulmonary fibrosis associated with poor prognosis. Wnt/β-catenin signaling is implicated in the development of fibrosis and is a therapeutic target for fibrotic diseases. Previous clinical studies of patients with pneumoconiosis, including silicosis, revealed an increased concentration of circulating WNT3A and DKK1 proteins and inflammatory cells in bronchoalveolar lavage compared with healthy subjects. The present study evaluated the effects of adenovirus-mediated transduction of Dickkopf-1 (Dkk1), a Wnt/β-catenin signaling inhibitor, on the development of pulmonary silicosis in mice. Consistent with previous human clinical studies, our experimental studies in mice demonstrated an aberrant Wnt/β-catenin signaling activity coinciding with increased Wnt3a and Dkk1 proteins and inflammation in lungs of silica-induced silicosis mice compared with controls. Intratracheal delivery of adenovirus expressing murine Dkk1 (AdDkk1) inhibited Wnt/β-catenin activity in mouse lungs. The adenovirus-mediated Dkk1 gene transduction demonstrated the potential to prevent silicosis development and ameliorate silica-induced lung fibrogenesis in mice, accompanied by the reduced expression of epithelia--mesenchymal transition markers and deposition of extracellular matrix proteins compared with mice treated with "null" adenoviral vector. Mechanistically, AdDkk1 is able to attenuate the lung silicosis by inhibiting a silica-induced spike in TGF-β/Smad signaling. In addition, the forced expression of Dkk1 suppressed silica-induced epithelial cell proliferation in polarized human bronchial epithelial cells. This study provides insight into the underlying role of Wnt/β-catenin signaling in promoting the pathogenesis of silicosis and is proof-of-concept that targeting Wnt/β-catenin signaling by Dkk1 gene transduction may be an alternative approach in the prevention and treatment of silicosis lung disease.

Combination Therapy with STAT3 Inhibitor Enhances SERCA2a-Induced BMPR2 Expression and Inhibits Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a devastating lung disease characterized by the progressive obstruction of the distal pulmonary arteries (PA). Structural and functional alteration of pulmonary artery smooth muscle cells (PASMC) and endothelial cells (PAEC) contributes to PA wall remodeling and vascular resistance, which may lead to maladaptive right ventricular (RV) failure and, ultimately, death. Here, we found that decreased expression of sarcoplasmic/endoplasmic reticulum Ca²⁺ ATPase 2a (SERCA2a) in the lung samples of PAH patients was associated with the down-regulation of bone morphogenetic protein receptor type 2 (BMPR2) and the activation of signal transducer and activator of transcription 3 (STAT3). Our results showed that the antiproliferative properties of SERCA2a are mediated through the STAT3/BMPR2 pathway. At the molecular level, transcriptome analysis of PASMCs co-overexpressing SERCA2a and BMPR2 identified STAT3 amongst the most highly regulated transcription factors. Using a specific siRNA and a potent pharmacological STAT3 inhibitor (STAT3i, HJC0152), we found that SERCA2a potentiated BMPR2 expression by repressing STAT3 activity in PASMCs and PAECs. In vivo, we used a validated and efficient model of severe PAH induced by unilateral left pneumonectomy combined with monocrotaline (PNT/MCT) to further evaluate the therapeutic potential of single and combination therapies using adeno-associated virus (AAV) technology and a STAT3i. We found that intratracheal delivery of AAV1 encoding SERCA2 or BMPR2 alone or STAT3i was sufficient to reduce the mean PA pressure and vascular remodeling while improving RV systolic pressures, RV ejection fraction, and cardiac remodeling. Interestingly, we found that combined therapy of AAV1.hSERCA2a with AAV1.hBMPR2 or STAT3i enhanced the beneficial effects of SERCA2a. Finally, we used cardiac magnetic resonance imaging to measure RV function and found that therapies using AAV1.hSERCA2a alone or combined with STAT3i significantly inhibited RV structural and functional changes in PNT/MCT-induced PAH. In conclusion, our study demonstrated that combination therapies using SERCA2a gene transfer with a STAT3 inhibitor could represent a new promising therapeutic alternative to inhibit PAH and to restore BMPR2 expression by limiting STAT3 activity.

The functions and regulation of Otubains in protein homeostasis and diseases

OTU domain-containing ubiquitin aldehyde-binding proteins Otubain1 (OTUB1) and Otubain2 (OTUB2) were initially identified as OTU deubiquitinases (DUBs). Recently, Otubains have emerged as essential regulators of diverse physiological processes, such as immune signaling and DNA damage response. Dysregulation of those processes is likely to increase the risk in multiple aspects of aging-related diseases, including cancers, neurodegenerative disorders, chronic kidney diseases, bone dysplasia and pulmonary fibrosis. Consistently, Otubains are aberrantly expressed in cancers and have been identified to be both tumor suppressors and tumor promoters in different types of cancers. Therefore, the regulatory mechanism of the activity and expression of Otubains is very important for better understanding of Otubains-associated biological networks and human diseases. This review provides a comprehensive description of functions and regulatory axis of Otubains, highlighting experimental evidences indicating Otubains as potential therapeutic targets against aging-related disorders.

Molecular and Genetic Profiling for Precision Medicines in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a rare and chronic lung disease characterized by progressive occlusion of the small pulmonary arteries, which is associated with structural and functional alteration of the smooth muscle cells and endothelial cells within the pulmonary vasculature. Excessive vascular remodeling is, in part, responsible for high pulmonary vascular resistance and the mean pulmonary arterial pressure, increasing the transpulmonary gradient and the right ventricular “pressure overload”, which may result in right ventricular (RV) dysfunction and failure. Current technological advances in multi-omics approaches, high-throughput sequencing, and computational methods have provided valuable tools in molecular profiling and led to the identification of numerous genetic variants in PAH patients. In this review, we summarized the pathogenesis, classification, and current treatments of the PAH disease. Additionally, we outlined the latest next-generation sequencing technologies and the consequences of common genetic variants underlying PAH susceptibility and disease progression. Finally, we discuss the importance of molecular genetic testing for precision medicine in PAH and the future of genomic medicines, including gene-editing technologies and gene therapies, as emerging alternative approaches to overcome genetic disorders in PAH.

Lung-targeted SERCA2a Gene Therapy: From Discovery to Therapeutic Application in Bleomycin-Induced Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease characterized by an accumulation of scar tissue within the lungs and the common presence of usual interstitial pneumonia. Unfortunately, only a few FDA-approved therapeutic options are currently available for the treatment of IPF and IPF remains associated with poor prognosis. Therefore, the identification of new pharmacological targets and strategies are critical for the treatment of IPF. This commentary aims to further discuss the role of sarcoplasmic reticulum Ca²⁺-ATPase 2a and its downstream signaling in IPF. Finally, this commentary offers new insights and perspectives regarding the therapeutic potential of AAV-mediated SERCA2A gene therapy as an emerging therapy for respiratory diseases.