[Risk Factors and a Prediction Model for Frequent Acute Exacerbations of Chronic Obstructive Pulmonary Disease].

Objective To identify the risk factors of patients with frequent acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and construct a prediction model based on the clinical data,providing a theoretical basis for the clinical prevention and treatment. Methods A total of 25 638 COPD patients admitted to the Department of Respiratory and Critical Care Medicine,the Third People's Hospital of Chengdu from January 1,2013 to May 1,2023 were selected.Among them,11 315 patients were included according to the inclusion and exclusion criteria,and their clinical characteristics were analyzed.Multivariate Logistic regression was carried out to identify the risk factors for frequent AECOPD.A nomogram model was utilized to quantify the risk of acute exacerbation,and the performance of the prediction model was assessed based on the area under the receiver operating characteristic (ROC) curve. Results In the patients with frequent AECOPD,male percentage (P<0.001),age (P<0.001),urban residence (P<0.001),smoking (P<0.001),length of stay (P<0.001),total cost (P<0.001),antibiotic cost (P<0.001),diabetes (P=0.003),respiratory failure (P<0.001),heart disease (P<0.001),application of systemic glucocorticoids (P<0.001),white blood cell count (P<0.001),neutrophil percentage (P<0.001),C-reactive protein (P<0.001),total cholesterol (P<0.001),and brain natriuretic peptide (BNP) (P<0.001) were all higher than those in the patients with infrequent AECOPD.Multivariate Logistic regression analysis revealed that age,urban residence,smoking,diabetes,heart disease,Pseudomonas aeruginosa infection,application of systemic glucocorticoids,antibiotics,respiratory failure,and elevated white blood cell count,total cholesterol,and BNP were independent risk factors for hospitalization due to frequent AECOPD.A nomogram model of hospitalization due to frequent AECOPD was constructed according to risk factors.The ROC curve was established to evaluate the performance of the model,which showed the area under the ROC curve of 0.899 (95%CI=0.892-0.905),the sensitivity of 85.30%,and the specificity of 79.80%. Conclusion Frequent AECOPD is associated with smoking,heart disease,application of systemic glucocorticoids,Pseudomonas aeruginosa infection,age,low body mass index,and elevated BNP.Predicting the risks of hospitalization due to frequent AECOPD by the established model can provide theoretical support for the treatment and risk factor management of the patients.

Clinical Features and a Prediction Model for Early Prediction of Composite Outcome in Chlamydia psittaci Pneumonia: A Multi-Centre Retrospective Study in China.

Introduction: C. psittaci pneumonia has atypical clinical manifestations and is often ignored by clinicians. This study analyzed the clinical characteristics, explored the risk factors for composite outcome and established a prediction model for early prediction of composite outcome among C. psittaci pneumonia patients. Methods: A multicenter, retrospective, observational cohort study was conducted in ten Chinese tertiary hospitals. Patients diagnosed with C. psittaci pneumonia were included, and their clinical data were collected and analyzed. The composite outcome of C. psittaci pneumonia included death during hospitalization, ICU admission, and mechanical ventilation. Univariate and multivariable logistic regression analyses were conducted to determine the significant variables. A ten-fold cross-validation was performed to internally validate the model. The model performance was evaluated using various methods, including receiver operating characteristics (ROC), C-index, sensitivity, specificity, positive/negative predictive value (PPV/NPV), decision curve analysis (DCA), and clinical impact curve analysis (CICA). Results: In total, 83 patients comprised training cohorts and 36 patients comprised validation cohorts. CURB-65 was used to establish predictive Model 1. Multivariate logistic regression analysis identified three independent prognostic factors, including serum albumin, CURB-65, and white blood cells. These factors were employed to construct model 2. Model 2 had acceptable discrimination (AUC of 0.898 and 0.825 for the training and validation sets, respectively) and robust internal validity. The specificity, sensitivity, NPV, and PPV for predicting composite outcome in the nomogram model were 91.7%, 84.5%, 50.0%, and 98.4% in the training sets, and 100.0%, 64.7%, 14.2%, and 100.0% in the validation sets. DCA and CICA showed that the nomogram model was clinically practical. Conclusion: This study constructs a refined nomogram model for predicting the composite outcome in C. psittaci pneumonia patients. This nomogram model enables early and accurate C. psittaci pneumonia patients' evaluation, which may improve clinical outcomes.

miR-30d Attenuates Pulmonary Arterial Hypertension via Targeting MTDH and PDE5A and Modulates the Beneficial Effect of Sildenafil.

Pulmonary arterial hypertension (PAH) is associated with aberrant pulmonary vascular smooth muscle cell (PASMC) function and vascular remodeling. MiR-30d plays an important role in the pathogenesis of several cardiovascular disorders. However, the function of miR-30d in PAH progression remained unknown. Our study shows that circulating miR-30d level is significantly reduced in the plasma from PAH patients. In miR-30d transgenic (TG) rats, overexpressing miR-30d attenuates monocrotaline (MCT)-induced pulmonary hypertension (PH) and pulmonary vascular remodeling. Increasing miR-30d also inhibits platelet-derived growth factor-bb (PDGF-bb)-induced proliferation and migration of human PASMC. Metadherin (MTDH) and phosphodiesterase 5A (PDE5A) are identified as direct target genes of miR-30d. Meanwhile, nuclear respiratory factor 1 (NRF1) acts as a positive upstream regulator of miR-30d. Using miR-30d knockout (KO) rats treated with sildenafil, a PDE5A inhibitor that is used in clinical PAH therapies, it is further found that suppressing miR-30d partially attenuates the beneficial effect of sildenafil against MCT-induced PH and vascular remodeling. The present study shows a protective effect of miR-30d against PAH and pulmonary vascular remodeling through targeting MTDH and PDE5A and reveals that miR-30d modulates the beneficial effect of sildenafil in treating PAH. MiR-30d should be a prospective target to treat PAH and pulmonary vascular remodeling.

Immunogenic cell death-related genes predict prognosis and response to immunotherapy in lung squamous cell carcinoma.

Lung squamous cell carcinoma (LUSC) is a malignancy with limited therapeutic options. Immunogenic cell death (ICD) has the potential to enhance the efficacy of cancer therapy by triggering immune responses. We aimed to explore the potential of ICD-based classification in predicting prognosis and response to immunotherapy for LUSC. RNA-seq information and clinical data of LUSC patients were obtained from The Cancer Genome Atlas (TCGA) dataset. ICD-related gene expressions in LUSC samples were analyzed by consensus clustering. Subsequently, differentially expressed genes (DEGs) between different ICD-related subsets were analyzed. Tumor mutation burden, immune cell infiltration, and survival analyses were conducted between different ICD subsets. Finally, an ICD-related risk signature was constructed and evaluated in LUSC patients, and the immunotherapy responses based on the gene expressions were also forecasted. ICD-high and ICD-low groups were defined, and 1466 DEGs were identified between the two subtypes. These DEGs were mainly enriched in collagen-containing extracellular matrix, cytokine-cytokine receptor interaction, the PI3K-Akt signaling pathway, and neuroactive ligand-receptor interaction. Furthermore, the ICD-low group exhibited a favorable prognosis, enhanced TTN and MUC16 mutation frequencies, increased infiltrating immune cells, and downregulated immune checkpoint expressions. Furthermore, we demonstrated that an ICD-related model (based on CD4, NLRP3, NT5E, and TLR4 genes) could forecast the prognosis of LUSC, and ICD risk scores were lower in the responder group. In summary, the predicted values of ICD-related genes (CD4, NLRP3, NT5E, and TLR4) for the prognosis and response to immunotherapy in LUSC were verified in the study, which benefits immunotherapy-based interventions for LUSC patients.

Nanoparticle-Patch System for Localized, Effective, and Sustained miRNA Administration into Infarcted Myocardium to Alleviate Myocardial Ischemia-Reperfusion Injury.

Timely blood reperfusion after myocardial infarction (MI) paradoxically triggers ischemia-reperfusion injury (I/RI), which currently has not been conquered by clinical treatments. Among innovative repair strategies for myocardial I/RI, microRNAs (miRNAs) are expected as genetic tools to rescue damaged myocardium. Our previous study identified that miR-30d can provide protection against myocardial apoptosis and fibrosis to alleviate myocardial injury. Although common methods such as liposomes and viral vectors have been used for miRNA transfection, their therapeutic efficiencies have struggled with inefficient in vivo delivery, susceptible inactivation, and immunogenicity. Here, we establish a nanoparticle-patch system for miR-30d delivery in a murine myocardial I/RI model, which contains ZIF-8 nanoparticles and a conductive microneedle patch. Loaded with miR-30d, ZIF-8 nanoparticles leveraging the proton sponge effect enable miR-30d to escape the endocytic pathway, thus avoiding premature degradation in lysosomes. Meanwhile, the conductive microneedle patch offers a distinct advantage by intramyocardial administration for localized, effective, and sustained miR-30d delivery, and it simultaneously releases Au nanoparticles to reconstruct electrical impulses within the infarcted myocardium. Consequently, the nanoparticle-patch system supports the consistent and robust expression of miR-30d in cardiomyocytes. Results from echocardiography and electrocardiogram (ECG) revealed improved heart functions and standard ECG wave patterns in myocardial I/RI mice after implantation of a nanoparticle-patch system for 3 and 6 weeks. In summary, our work incorporated conductive microneedle patch and miR-30d nanodelivery systems to synergistically transcend the limitations of common RNA transfection methods, thus mitigating myocardial I/RI.

The landscape of epigenetic regulation and therapeutic application of N6-methyladenosine modifications in non-coding RNAs.

RNA N6-methyladenosine (m6A) methylation is the most abundant and conserved RNA modification in eukaryotes. It participates in the regulation of RNA metabolism and various pathophysiological processes. Non-coding RNAs (ncRNAs) are defined as small or long transcripts which do not encode proteins and display numerous biological regulatory functions. Similar to mRNAs, m6A deposition is observed in ncRNAs. Studying RNA m6A modifications on ncRNAs is of great importance specifically to deepen our understanding of their biological roles and clinical implications. In this review, we summarized the recent research findings regarding the mutual regulation between RNA m6A modification and ncRNAs (with a specific focus on microRNAs, long non-coding RNAs, and circular RNAs) and their functions. We also discussed the challenges of m6A-containing ncRNAs and RNA m6A as therapeutic targets in human diseases and their future perspective in translational roles.

Directional Electron Flow in a Selenoviologen-Based Tetracationic Cyclophane for Enhanced Visible-Light-Driven Hydrogen Evolution.

Directional electron flow in the photocatalyst enables efficient charge separation, which is essential for efficient photocatalysis of H2 production. Here, we report a novel class of tetracationic cyclophanes (7) incorporating bipyridine Pt(II) and selenoviologen. X-ray single-crystal structures reveal that 7 not only fixes the distances and spatial positions between its individual units but also exhibits a box-like rigid electron-deficient cavity. Moreover, host-guest recognition phenomena are observed between 7 and ferrocene, forming host-guest complexes with a 1:1 stoichiometry in MeCN. 7 exhibits good redox properties, narrow energy gaps, and strong absorption in the visible range (370-500 nm) due to containing two selenoviologen (SeV2+) units. Meanwhile, the femtosecond transient absorption (fs-TA) reveals that 7 has stabilized dicationic biradical, efficient charge separation, and facilitates directional electron flow to achieve efficient electron transfer due to the formation of rigid cyclophane and electronic architecture. Then, 7 is applied to visible-light-driven hydrogen evolution with high hydrogen production (132 µmol), generation rate (11 µmol/h), turnover number (221), and apparent quantum yield (1.7%), which provides a simplified and efficient photocatalytic strategy for solar energy conversion.

Clinical and pathological analyses of 14 cases of angiomatoid fibrous histiocytoma.

Angiomatoid fibrous histiocytoma (AFH) is a soft tissue tumor of uncertain differentiation. Although its prognosis is good, its diagnosis and differential diagnosis remain a challenge, particularly for tumors with an atypical morphology. We evaluated the clinicopathological characteristics of 14 AFH cases and examined the key factors in its diagnosis or differential diagnosis. The cohort comprised 6 men and 8 women aged 9-65 years (average age: 31.2 years). Most of the tumors (11/14, 79%) were located in soft tissues, whereas 3/14 (21%) were located in the lung (1 case) and brain (2 cases). Tumor cells were spindle-shaped to epithelioid, with a visible fibrous capsule (9/14, 64%), hemorrhagic gap (9/14, 64%), lymphocyte sleeve (7/14, 50%), necrosis (3/14, 21%), and infiltrative boundary (4/14, 29%). The tumors expressed desmin (10/14, 71%) and exhibited low levels of Ki-67. 13 cases (93%) displayed ESWSR1 gene rearrangement. At follow-up, 1 case (7%) experienced local tumor recurrence. AFH is a rare intermediate tumor. Its pathological diagnosis requires a comprehensive analysis of histological, immunophenotypic, and molecular genetic features to avoid misdiagnosis. Our study has further enriched the histological features of AFH, emphasizing the importance of differential diagnosis and providing a reference for clinical practice.

Droplet Micro-Sensor and Detection of Respiratory Droplet Transmission.

Droplet transmission is the primary infection route for respiratory diseases like COVID-19 and influenza, but small and low-cost wearable droplet detection devices are a significant challenge. Herein, a respiratory droplet micro-sensor based on graphene oxide quantum dots (GOQDs) assembled onto SiO2 microspheres by the nebulized natural deposition is presented. Benefiting from the energy dissipation of the microsphere to droplets, the sensor can detect droplets as far as 2 m from coughing. With this sensor, droplet signal variations caused by some factors like distance, speech, angles, and wind directions are explored, and the effectiveness of different protective measures in preventing droplet transmission is evaluated. This droplet detection technology is expected to be utilized for the development of personal detection and protection devices against infectious respiratory diseases.

Regulation of SETD2 maintains immune regulatory function in macrophages to suppress airway allergy.

SET domain-containing 2 (SETD2) is a histone methyltransferase. It regulates the activity of H3K36me3 to enhance gene transcription. Macrophages (Mϕs) are one of the cell types involved in immune response. The purpose of this study is to clarify the role of SETD2 in regulating the immune property of Mϕ. The Mφs were isolated from the bronchoalveolar lavage fluid (BALF) and analysed through flow cytometry and RNA sequencing. A mouse strain carrying Mφs deficient in SETD2 was used. A mouse model of airway allergy was established with the ovalbumin/alum protocol. Less expression of SETD2 was observed in airway Mϕs in patients with allergic asthma. SETD2 of M2 cells was associated with the asthmatic clinical response. Sensitization reduced the expression of SETD2 in mouse respiratory tract M2 cells, which is associated with the allergic reaction. Depletion of SETD2 in Mφs resulted in Th2 pattern inflammation in the lungs. SETD2 maintained the immune regulatory ability in airway M2 cells. SETD2 plays an important role in the maintenance of immune regulatory property of airway Mφs.

KLF15-activated MARCH2 boosts cell proliferation and epithelial-mesenchymal transition and presents diagnostic significance for hepatocellular carcinoma.

PURPOSE: Membrane associated ubiquitin ligase MARCH2 majorly involves in inflammation response and protein trafficking. However, its comprehensive role in hepatocellular carcinoma (HCC) is largely unknown. METHODS: Firstly, multiple bioinformatic analyses were applied to determine MARCH2 mRNA level, its expression comparison in diverse molecular and immune subtypes, and diagnostic value in HCC. Subsequently, RNA-seq, real-time quantitative PCR, immunohistochemistry and cell proliferation assay are used to explore the epithelial-mesenchymal transition (EMT) and proliferation by gene-silencing or overexpressing in cultured HCC cells or in vivo xenograft. Moreover, dual luciferase reporter assay and immunoblotting are delved into verify the transcription factor that activating MARCH2 promoter. RESULTS: Multiple bioinformatic analyses demonstrate that MARCH2 is upregulated in multiple cancer types and exhibits startling diagnostic value as well as distinct molecular and immune subtypes in HCC. RNA-seq analysis reveals MARCH2 may promote EMT, cell proliferation and migration in HepG2 cells. Furthermore, overexpression of MARCH2 triggers EMT and significantly enhances HCC cell migration, proliferation and colony formation in a ligase activity-dependent manner. Additionally, above observations are validated in the HepG2 mice xenografts. For up-stream mechanism, transcription factor KLF15 is highly expressed in HCC and activates MARCH2 expression. CONCLUSION: KLF15 activated MARCH2 triggers EMT and serves as a fascinating biomarker for precise diagnosis of HCC. Consequently, MARCH2 emerges as a promising candidate for target therapy in cancer management.

Deciphering the microbial landscape of lower respiratory tract infections: insights from metagenomics and machine learning.

Background: Lower respiratory tract infections represent prevalent ailments. Nonetheless, current comprehension of the microbial ecosystems within the lower respiratory tract remains incomplete and necessitates further comprehensive assessment. Leveraging the advancements in metagenomic next-generation sequencing (mNGS) technology alongside the emergence of machine learning, it is now viable to compare the attributes of lower respiratory tract microbial communities among patients across diverse age groups, diseases, and infection types. Method: We collected bronchoalveolar lavage fluid samples from 138 patients diagnosed with lower respiratory tract infections and conducted mNGS to characterize the lung microbiota. Employing various machine learning algorithms, we investigated the correlation of key bacteria in patients with concurrent bronchiectasis and developed a predictive model for hospitalization duration based on these identified key bacteria. Result: We observed variations in microbial communities across different age groups, diseases, and infection types. In the elderly group, Pseudomonas aeruginosa exhibited the highest relative abundance, followed by Corynebacterium striatum and Acinetobacter baumannii. Methylobacterium and Prevotella emerged as the dominant genera at the genus level in the younger group, while Mycobacterium tuberculosis and Haemophilus influenzae were prevalent species. Within the bronchiectasis group, dominant bacteria included Pseudomonas aeruginosa, Haemophilus influenzae, and Klebsiella pneumoniae. Significant differences in the presence of Pseudomonas phage JBD93 were noted between the bronchiectasis group and the control group. In the group with concomitant fungal infections, the most abundant genera were Acinetobacter and Pseudomonas, with Acinetobacter baumannii and Pseudomonas aeruginosa as the predominant species. Notable differences were observed in the presence of Human gammaherpesvirus 4, Human betaherpesvirus 5, Candida albicans, Aspergillus oryzae, and Aspergillus fumigatus between the group with concomitant fungal infections and the bacterial group. Machine learning algorithms were utilized to select bacteria and clinical indicators associated with hospitalization duration, confirming the excellent performance of bacteria in predicting hospitalization time. Conclusion: Our study provided a comprehensive description of the microbial characteristics among patients with lower respiratory tract infections, offering insights from various perspectives. Additionally, we investigated the advanced predictive capability of microbial community features in determining the hospitalization duration of these patients.

Preparation of Polydopamine Functionalized HNIW Crystals and Application in Solid Propellants.

The application of hexanitrohexaazaisowurtzitane (HNIW) as an oxidizer in solid propellants aligns with the pursuit of high-energy materials. However, the phase transformation behavior and high impact sensitivity of HNIW are its limitations. Due to the strong adhesion and mild synthesis conditions, polydopamine (PDA) has been employed to modify HNIW. However, the method suffers from a slow coating process and a non-ideal coating effect under short reaction time. Herein, oxygen-accelerated dopamine in situ polymerization coating method was developed. It was found that oxygen not only reduced the coating time but also contributed to forming a dense and uniform PDA layer. HNIW@PDA coated in oxygen for 6 h exhibited the most favorable performance, with a delay of 20.8 °C in the phase transition temperature and a reduction of 145.45% in the impact sensitivity. The -OH groups on the surface of PDA enhanced the interaction between HNIW and polymer binders, resulting in a 20.36% reduction in the dewetting percentage. The lower content of PDA in HNIW@PDA (1.17%) resulted in minimal variation in the heat of explosion for HNIW@PDA-based HTPB propellant (6287 kJ/kg) in comparison to HNIW-based HTPB propellant (6297 kJ/kg). Hence, HNIW@PDA-based propellants are expected to offer an alternative with promising safety and mechanical performance compared to existing HNIW-based propellants, thus facilitating the application of HNIW in high-energy propellants. This work presents a low-cost method for efficiently inhibiting the phase transformation of polycrystalline explosives and reducing the impact sensitivity. It also offers a potential approach to enhance the interfacial interaction between nitro-containing explosives and polymer binders.

Characterization of the immune suppressive functions of eosinophils.

Eosinophils account for a significant portion of immune cells in the body. It is well known that eosinophils play a role in the pathogenesis of many diseases. In which the interaction between eosinophils and other immune cells is incompletely understood. The aim of this study is to characterize the immune suppressive functions of eosinophils. In this study, an irway allergy mouse model was established. Eosinophils were isolated from the airway tissues using flow cytometry cell sorting. The RAW264.7 cell line was used to test the immune suppressive functions of eosinophils. We observed that eosinophils had immune suppressive functions manifesting inhibiting immune cell proliferation and cytokine release from other immune cells. The eosinophil's immune suppressive functions were mediated by eosinophil-derived molecules, such as eosinophil peroxidase (EPX) and major basic protein (MBP). The expression of Ras-like protein in the brain 27a (Rab27a) was detected in eosinophils, which controlled the release of MBP and EPX by eosinophils. Eosinophil mediators had two contrast effects on inducing inflammatory responses or rendering immune suppressive effects, depending on the released amounts. Administration of an inhibitor of Rab27a at proper dosage could alleviate experimental airway allergy. To sum up, eosinophils have immune suppressive functions and are also inflammation inducers. Rab27a governs the release of EPX and MBP from eosinophils, which leads to immune suppression or inflammation. Modulation of Rab27a can alleviate airway allergy responses by modulating eosinophil's immune suppressive functions, which has the translational potential for the management of eosinophil-related diseases.

Consensus statement of Chinese experts on exercise prescription (2023).

Exercise prescriptions play a vital role in the prevention and treatment of chronic diseases. A consensus regarding exercise prescription is important for physical health. The "Consensus statement of Chinese experts on exercise prescription" (hereinafter referred to as "Expert Consensus") divides exercise prescription into two categories: fitness exercise prescription and medical exercise prescription. Traditional Chinese fitness exercises, exercise risk, exercise prescription, and basic precautions for exercise prescription are explained.

Inhibition of Hmbox1 Promotes Cardiomyocyte Survival and Glucose Metabolism Through Gck Activation in Ischemia/Reperfusion Injury.

BACKGROUND: Exercise-induced physiological cardiac growth regulators may protect the heart from ischemia/reperfusion (I/R) injury. Homeobox-containing 1 (Hmbox1), a homeobox family member, has been identified as a putative transcriptional repressor and is downregulated in the exercised heart. However, its roles in exercise-induced physiological cardiac growth and its potential protective effects against cardiac I/R injury remain largely unexplored. METHODS: We studied the function of Hmbox1 in exercise-induced physiological cardiac growth in mice after 4 weeks of swimming exercise. Hmbox1 expression was then evaluated in human heart samples from deceased patients with myocardial infarction and in the animal cardiac I/R injury model. Its role in cardiac I/R injury was examined in mice with adeno-associated virus 9 (AAV9) vector-mediated Hmbox1 knockdown and in those with cardiac myocyte-specific Hmbox1 ablation. We performed RNA sequencing, promoter prediction, and binding assays and identified glucokinase (Gck) as a downstream effector of Hmbox1. The effects of Hmbox1 together with Gck were examined in cardiomyocytes to evaluate their cell size, proliferation, apoptosis, mitochondrial respiration, and glycolysis. The function of upstream regulator of Hmbox1, ETS1, was investigated through ETS1 overexpression in cardiac I/R mice in vivo. RESULTS: We demonstrated that Hmbox1 downregulation was required for exercise-induced physiological cardiac growth. Inhibition of Hmbox1 increased cardiomyocyte size in isolated neonatal rat cardiomyocytes and human embryonic stem cell-derived cardiomyocytes but did not affect cardiomyocyte proliferation. Under pathological conditions, Hmbox1 was upregulated in both human and animal postinfarct cardiac tissues. Furthermore, both cardiac myocyte-specific Hmbox1 knockout and AAV9-mediated Hmbox1 knockdown protected against cardiac I/R injury and heart failure. Therapeutic effects were observed when sh-Hmbox1 AAV9 was administered after I/R injury. Inhibition of Hmbox1 activated the Akt/mTOR/P70S6K pathway and transcriptionally upregulated Gck, leading to reduced apoptosis and improved mitochondrial respiration and glycolysis in cardiomyocytes. ETS1 functioned as an upstream negative regulator of Hmbox1 transcription, and its overexpression was protective against cardiac I/R injury. CONCLUSIONS: Our studies unravel a new role for the transcriptional repressor Hmbox1 in exercise-induced physiological cardiac growth. They also highlight the therapeutic potential of targeting Hmbox1 to improve myocardial survival and glucose metabolism after I/R injury.

Recombinant hirudin attenuates pulmonary hypertension and thrombosis in acute pulmonary embolism rat model.

Background: Acute pulmonary embolism (APE) is classified as a subset of diseases that are characterized by lung obstruction due to various types of emboli. Current clinical APE treatment using anticoagulants is frequently accompanied by high risk of bleeding complications. Recombinant hirudin (R-hirudin) has been found to have antithrombotic properties. However, the specific impact of R-hirudin on APE remains unknown. Methods: Sprague-Dawley (SD) rats were randomly assigned to five groups, with thrombi injections to establish APE models. Control and APE group rats were subcutaneously injected with equal amounts of dimethyl sulfoxide (DMSO). The APE+R-hirudin low-dose, middle-dose, and high-dose groups received subcutaneous injections of hirudin at doses of 0.25 mg/kg, 0.5 mg/kg, and 1.0 mg/kg, respectively. Each group was subdivided into time points of 2 h, 6 h, 1 d, and 4 d, with five animals per point. Subsequently, all rats were euthanized, and serum and lung tissues were collected. Following the assessment of right ventricular pressure (RVP) and mean pulmonary artery pressure (mPAP), blood gas analysis, enzyme-linked immunosorbnent assay (ELISA), pulmonary artery vascular testing, hematoxylin-eosin (HE) staining, Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining, immunohistochemistry, and Western blot experiments were conducted. Results: R-hirudin treatment caused a significant reduction of mPAP, RVP, and Malondialdehyde (MDA) content, as well as H2O2 and myeloperoxidase (MPO) activity, while increasing pressure of oxygen (PaO2) and Superoxide Dismutase (SOD) activity. R-hirudin also decreased wall area ratio and wall thickness to diameter ratio in APE rat pulmonary arteries. Serum levels of endothelin-1 (ET-1) and thromboxaneB2 (TXB2) decreased, while prostaglandin (6-K-PGF1α) and NO levels increased. Moreover, R-hirudin ameliorated histopathological injuries and reduced apoptotic cells and Matrix metalloproteinase-9 (MMP9), vascular cell adhesion molecule-1 (VCAM-1), p-Extracellular signal-regulated kinase (ERK)1/2/ERK1/2, and p-P65/P65 expression in lung tissues. Conclusion: R-hirudin attenuated pulmonary hypertension and thrombosis in APE rats, suggesting its potential as a novel treatment strategy for APE.

Erythropoietin alleviates lung ischemia-reperfusion injury by activating the FGF23/FGFR4/ERK signaling pathway.

Background: The purpose of the present study was to investigate the effect of erythropoietin (EPO) on lung ischemia-reperfusion injury (LIRI). Methods: Sprague Dawley rats and BEAS-2B cells were employed to construct an ischemia-reperfusion (I/R)-induced model in vivo and in vitro, respectively. Afterward, I/R rats and tert-butyl hydroperoxide (TBHP)-induced cells were treated with different concentrations of EPO. Furthermore, 40 patients with LIRI and healthy controls were enrolled in the study. Results: It was observed that lung tissue damage, cell apoptosis and the expression of BAX and caspase-3 were higher in the LIRI model in vivo and in vitro than in the control group, nevertheless, the Bcl-2, FGF23 and FGFR4 expression level was lower than in the control group. EPO administration significantly reduced lung tissue damage and cell apoptosis while also up-regulating the expression of FGF23 and FGFR4. Rescue experiments indicated that EPO exerted a protective role associated with the FGF23/FGFR4/p-ERK1/2 signal pathway. Notably, the expression of serum EPO, FGF23, FGFR4 and Bcl-2 was decreased in patients with LIRI, while the expression of caspase-3 and BAX was higher. Conclusion: EPO could effectively improve LIRI, which might be related to the activation of the FGF23/FGFR4/p-ERK1/2 signaling pathway.

Exercise training decreases lactylation and prevents myocardial ischemia-reperfusion injury by inhibiting YTHDF2.

Exercise improves cardiac function and metabolism. Although long-term exercise leads to circulating and micro-environmental metabolic changes, the effect of exercise on protein post-translational lactylation modifications as well as its functional relevance is unclear. Here, we report that lactate can regulate cardiomyocyte changes by improving protein lactylation levels and elevating intracellular N6-methyladenosine RNA-binding protein YTHDF2. The intrinsic disorder region of YTHDF2 but not the RNA m6A-binding activity is indispensable for its regulatory function in influencing cardiomyocyte cell size changes and oxygen glucose deprivation/re-oxygenation (OGD/R)-stimulated apoptosis via upregulating Ras GTPase-activating protein-binding protein 1 (G3BP1). Downregulation of YTHDF2 is required for exercise-induced physiological cardiac hypertrophy. Moreover, myocardial YTHDF2 inhibition alleviated ischemia/reperfusion-induced acute injury and pathological remodeling. Our results here link lactate and lactylation modifications with RNA m6A reader YTHDF2 and highlight the physiological importance of this innovative post-transcriptional intrinsic regulation mechanism of cardiomyocyte responses to exercise. Decreasing lactylation or inhibiting YTHDF2/G3BP1 might represent a promising therapeutic strategy for cardiac diseases.