Pulmonary Tissue Research Articles

Asbestos exposure diagnosis in pulmonary tissues.

The diagnosis of asbestosis requires different criteria depending on whether it is in a clinical or medical/legal setting. In the latter context, only when a "diffuse interstitial fibrosis associated to asbestos bodies (ABs)" is present, it can be said to be asbestosis. Considering the medical/legal setting, the diagnosis must be certain and proven. Unfortunately, it is often difficult to identify ABs by light microscopy (LM), but this does not mean that the diagnosis should be clinically excluded. Other parameters are important, such as working history and/or diagnostic imaging. In addition to LM, normally used for diagnosis, there are other techniques, e.g.: scanning electron microscopy with attached microanalysis microprobe (SEM/EDS), but they require tissue digestion and higher cost. A new approach with micro-Raman spectroscopy and SEM/EDS techniques is able to analyse histological sections without other manipulations that could interfere with analysis of asbestos fibres. In this work, we propose an algorithm for asbestosis diagnosis, especially in the forensic medical field, demonstrating the importance of close collaboration between multiple professionals.

Trimetazidine Alleviates Bleomycin-Induced Pulmonary Fibrosis by Targeting the Long Noncoding RNA CBR3-AS1-Mediated miRNA-29 and Resistin-Like Molecule alpha 1: Deciphering a Novel Trifecta Role of LncRNA CBR3-AS1/miRNA-29/FIZZ1 Axis in Lung Fibrosis.

Pulmonary fibrosis (PF) and tissue remodeling can greatly impair pulmonary function and often lead to fatal outcomes. In the present study, we explored a novel molecular interplay of long noncoding (Lnc) RNA CBR3-AS1/ miRNA-29/ FIZZ1 axis in moderating the inflammatory processes, immunological responses, and oxidative stress pathways in bleomycin (BLM)-induced lung fibrosis. Furthermore, we investigated the pharmacological potential of Trimetazidine (TMZ) in ameliorating lung fibrosis. Our results revealed that the BLM-treated group exhibited a significant upregulation in the expression of epigenetic regulators, lncRNA CBR3-AS1 and FIZZ1, compared to the control group (P<0.0001), along with the downregulation of miRNA-29 expression. Furthermore, Correlation analysis showed a significant positive association between lnc CBR3-AS1 and FIZZ1 (R=0.7723, p<0.05) and a significant negative association between miRNA-29 and FIZZ1 (R=-0.7535, p<0.05), suggesting lnc CBR3-AS1 as an epigenetic regulator of FIZZ1 in lung fibrosis. BLM treatment significantly increased the expression of Notch, Jagged1, Smad3, TGFB1, and hydroxyproline. Interestingly, the administration of TMZ demonstrated the ability to attenuate the deterioration effects caused by BLM treatment, as indicated by biochemical and histological analyses. Our investigations revealed that the therapeutic potential of TMZ as an antifibrotic drug could be ascribed to its ability to directly target the epigenetic regulators lncRNA CBR3-AS1/ miRNA-29/ FIZZ1, which in turn resulted in the mitigation of lung fibrosis. Histological and immunohistochemical analyses further validated the potential antifibrotic effects of TMZ by mitigating the structural damage associated with fibrosis. Taken together, our study showed for the first time the interplay between epigenetic lncRNAs CBR3-AS1 and miRNA-29 in lung fibrosis and demonstrated that FIZZ1 could be a downregulatory gene for lncRNA CBR3-AS1 and miRNA-29. Our key findings demonstrate that TMZ significantly reduces the expression of fibrotic, oxidative stress, immunomodulatory, and inflammatory markers, along with epigenetic regulators associated with lung fibrosis. This validates its potential as an effective antifibrotic agent by targeting the CBR3-AS1/miRNA-29/FIZZ1 axis.

Rare interstitial lung diseases: a narrative review.

Interstitial lung diseases (ILDs) encompass over 200 entities. Among them, fibrosing lung diseases, have recently generated special interest due to the emerging therapies for their management. However, it is important to deepen our knowledge of other less prevalent ILD, since many of them are associated with a poor prognosis. This narrative review aims to provide a practical and up-to-date description of some poorly recognized ILD. It covers rare idiopathic interstitial pneumonias and their histologic patterns, genetic disorders with interstitial lung involvement (Hermansky-Pudlak syndrome), and ILD associated with benign proliferation of pulmonary lymphoid tissue, namely follicular bronchiolitis and granulomatous-lymphocytic interstitial lung disease. Electronic searches of PubMed and Google Scholar using specific keywords were conducted. Articles underwent screening for relevance, covering review articles, meta-analyses, systematic reviews, case series, prospective studies, society guidelines, editorials in peer-reviewed journals; scientific books on the subject. The data included was limited to English and Spanish publications. Despite the low prevalence of these diseases, the increased recognition of radiological patterns, pathological features, and diagnostic procedures, have permitted their better characterization. This review highlights epidemiology, clinical presentation, diagnosis, natural history, and treatment. Lesser-studied ILD represent a diagnostic and therapeutic challenge and can be frequently misdiagnosed. Also, due to the lack of randomized controlled trials, there are no well-established therapeutic options. Further studies or registries are needed to improve accurate diagnosis and management.

Risk of Pulmonary Diseases in Osteogenesis Imperfecta in Denmark: A Register-Based Cohort Study

Osteogenesis imperfecta (OI) is a rare hereditary disease mainly resulting in reduced or altered collagen type I. Collagen type I is a major constituent of the respiratory system, and normal collagen type I is vital for pulmonary tissue function. Do patients with OI have increased admission rates resulting from pulmonary diseases compared with the general population? This was a register-based, nationwide cohort study, including all patients with OI in Denmark and a reference population. From January 1, 1995, through December 31, 2018, we evaluated the rates of admissions resulting from asthma, COPD, and pneumonia as well as the use of bronchodilator drugs and antibiotics comparing individuals with OI with the reference population. We included 862 individuals with OI and 4,283 people from the reference population covering 15,952 and 79,471 person-years of observation, respectively, in the two cohorts. The admissions rate (incidence rate [IR]) was highest in women with OI 65 years of age or older, with 56.3 admissions per 1,000 person-years and 29.4 admissions per 1,000 person-years in the reference population (amounting to an admissions incident rate ratio [IRR] of 1.91 [95%CI, 1.38-2.70]). The highest admission rate in men with OI was found among participants 0 to 18 years of age, with an IR of 30.4 per 1,000 person-years compared with an IR of 7.7 per 1,000 person-years in the reference population (IRR, 4.92 [95%CI, 3.79-6.38]). We found a higher proportion of long-acting and short-acting bronchodilator drug users in the OI cohort, but no increased use of antibiotics. Overall, the admission rates for respiratory diseases were low in the OI cohort, but a higher relative risk of hospitalizations resulting from respiratory disease compared with the general population. Timely diagnosis and treatment of respiratory complications in individuals with OI is warranted.

Therapeutic effects of Tocilizumab on COVID-19

Critical lung damage and death are the most profound outcomes associated with the cytokine storm induced by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). It is well known that COVID-19 in many patients triggers hyperactivation of the immune system, resulting in the release of a diverse set of cytokine signal molecules in the pulmonary tissue, leading to a potentially lethal hyperinflammatory condition. One cytokine found to play a central role in this outcome is interleukin-6 (IL-6). Therefore, preventing IL-6 signaling could potentially improve patient outcomes. Tocilizumab is an IL-6 receptor agonist originally approved by the FDA to treat rheumatoid arthritis, which was found to be effective at reducing the mortality of patients with moderate to severe COVID-19 symptoms through prevention of the aforementioned induced cytokine storm. Clinical trials have supported this conclusion and will be addressed, such as the RECOVERY and COVACTA trials. Results have shown a decrease in mortality, as well as an increase in discharge rate. Future research is needed to elucidate the molecular mechanisms as well as the therapeutic roles of Tocilizumab on COVID-19 and similar pneumonia by virus infections.

Cortex Mori Radicis[Morus Alba L. (Moraceae)] extract alleviates senescence via PI3K/Akt signaling in COPD fibroblasts

BackgroundChronic obstructive pulmonary disease (COPD) is marked by prolonged exposure to cigarette smoke, which accelerates senescence in lung fibroblasts and contributes to lung fibrosis. Cortex Mori Radicis [Morus albal. (Moraceae)], a traditional Chinese medicinal herb known for its antitussive properties, has emerged as a potential therapeutic agent for COPD. This study aims to elucidate the immunological mechanisms by which Cortex Mori Radicis mitigates COPD progression, utilizing a mouse model and the MRC-5 cell line. Methods and ResultsCOPD mouse models were established through chronic cigarette smoke (CS) exposure, followed by isolation of lung fibroblasts. Senescence markers and inflammatory mediators were assessed in both the isolated cells and the mice. Lung fibroblasts and bleomycin (Bleomycin)-treated MRC-5 cells exhibited elevated expression of senescence markers, including senescence-associated beta-galactosidase activity, p16INK4A, p21, p38 MAPK, and p53, along with increased levels of senescence-associated secretory phenotype (SASP) mRNA, such as IL-6 and IL-8. Treatment with Cortex Mori Radicis significantly attenuated the protein levels of these senescence markers and reduced SASP mRNA expression. Furthermore, integration of transcriptomic data from lung tissues and primary fibroblasts, combined with network pharmacology analysis, indicated that Cortex Mori Radicis inhibits fibroblast senescence via the PI3K/Akt pathway, thereby ameliorating lung pathology in COPD mice. ConclusionThrough the application of transcriptomics and network analysis, this study identifies that Cortex Mori Radicis suppresses cigarette smoke-induced senescence in pulmonary tissues and bleomycin (Bleomycin)-exposed MRC-5 cells by targeting the PI3K/Akt signaling pathway. These findings underscore the therapeutic potential of Cortex Mori Radicis as a novel intervention for COPD.

Cell‐type‐specific mRNA m6A landscape and regulatory mechanisms underlying pulmonary injury in COVID‐19

AbstractCoronavirus disease 2019 (COVID‐19) pandemic has caused millions of deaths. The risk of COVID‐19 spreading still exists after the deconfinement act, Omicron became the dominant variant. Although N6‐methyladenosine (m6A) regulators has been reported to affect the pathogenicity of COVID‐19, their mechanism in the progression of lung injury in COVID‐19 patients remain elusive. Here we show the landscape and specific mechanisms of m6A regulators in lung tissues through single‐nucleus RNA sequencing (snRNA‐Seq) data sets of 116,252 cells, and the external validation was performed using data from another snRNA‐Seq data. The m6A reader IGF2BP2 was specifically upregulated in alveolar type I (AT1) cells, resulting in impaired lung regeneration. ALKBH5 expression upregulation in macrophages, impairing immune responses. Moreover, WTAP markedly upregulated in fibroblasts, leading to pulmonary fibrosis. In addition, m6A regulators dysregulation induced aberrant cell–cell communication in pulmonary tissue and mediated ligand–receptor interactions across diverse cell types in lung tissues by activating the TGF‐β signaling pathway. Overall, these results indicated that the upregulation of m6A regulators in alveolar cells, myeloid cells, and fibroblasts may induce pulmonary injury in patients. The development of m6A‐regulator inhibitors could be as one potential antifibrotic drugs for COVID‐19.

Pulmonary mucosa-associated lymphoid tissue lymphoma: insights from a 15-year study at a single institution involving 14 clinical cases

ObjectiveThis study aims to delineate the clinical presentations, imaging features, pathological characteristics, therapeutic strategies, and outcomes of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma, thereby deducing the most efficacious treatment paradigm.MethodsWe conducted a retrospective review of 14 patients diagnosed with pulmonary MALT lymphoma at the Second Xiangya Hospital, affiliated with Central South University, between September 2007 and September 2022, focusing on their clinical profiles, diagnostic pathways, treatment modalities, and prognostic outcomes.ResultsThe cohort’s median age was 60 years (ranging from 44 to 81 years), with 64.29% being female and only 14.29% having a history of smoking. The incidence of immunodeficiency diseases among the patients was notably low. Imaging typically revealed pulmonary nodules and masses, with air bronchogram signs evident in 9 patients and pleural effusion in 2. CD20 expression was markedly positive across the board in all patients with pulmonary MALT lymphoma. Among the 12 patients who received intervention, 6 were treated with chemotherapy alone, 2 underwent surgical resection, and 4 benefitted from a combined approach of chemotherapy and surgery. Over the monitoring period, 2 patients succumbed to their disease. The estimated 5- and 10-year overall survival (OS) rates were 91.67% and 76.39%, respectively, with the median progression-free survival (PFS) reaching 7 years. Comparative analysis revealed no significant disparity in PFS between patients treated exclusively with chemotherapy and those receiving both chemotherapy and surgical intervention (P = 0.22).ConclusionPulmonary MALT lymphoma typically exhibits a slow course, with gradual progression and a predominantly positive prognosis. Chemotherapy emerges as the preferred therapeutic option for managing this malignancy.

Pneumococcal Neuraminidases Increase Platelet Killing by Pneumolysin.

Platelets prevent extravasation of capillary fluids into the pulmonary interstitial tissue by sealing gaps in inflamed endothelium. This reduces respiratory distress associated with pneumonia. Streptococcus pneumoniae is the leading cause of severe community-acquired pneumonia. Pneumococci produce pneumolysin (PLY), which forms pores in membranes of eukaryotic cells including platelets. Additionally, pneumococci express neuraminidases, which cleave sialic acid residues from eukaryotic glycoproteins. In this study, we investigated the effect of desialylation on PLY binding and pore formation on platelets. We incubated human platelets with purified neuraminidases and PLY, or nonencapsulated S. pneumoniae D39/TIGR4 and isogenic mutants deficient in PLY and/or NanA. We assessed platelet desialylation, PLY binding, and pore formation by flow cytometry. We also analyzed the inhibitory potential of therapeutic immunoglobulin G preparations (IVIG [intravenous immunoglobulin]). Wild-type pneumococci cause desialylation of platelet glycoproteins by neuraminidases, which is reduced by 90 to 100% in NanA-deficient mutants. NanC, cleaving only α2,3-linked sialic acid, induced platelet desialylation. PLY binding to platelets then x2doubled (p = 0.0166) and pore formation tripled (p = 0.0373). A neuraminidase cleaving α2,3-, α2,6-, and α2,8-linked sialic acid like NanA was even more efficient. Addition of polyvalent IVIG (5 mg/mL) decreased platelet desialylation induced by NanC up to 90% (p = 0.263) and reduced pore formation >95% (p < 0.0001) when incubated with pneumococci. Neuraminidases are key virulence factors of pneumococci and desialylate platelet glycoproteins, thereby unmasking PLY-binding sites. This enhances binding of PLY and pore formation showing that pneumococcal neuraminidases and PLY act in concert to kill platelets. However, human polyvalent immunoglobulin G preparations are promising agents for therapeutic intervention during severe pneumococcal pneumonia.

Lipid nanoparticle encapsulation of a Delta spike-CD40L DNA vaccine improves effectiveness against Omicron challenge in Syrian hamsters

The effectiveness of mRNA vaccines largely depends on their lipid nanoparticle (LNP) component. Herein, we investigate the effectiveness of DLin-KC2-DMA (KC2) and SM-102-based LNPs for the intramuscular delivery of a plasmid encoding B.1.617.2 (Delta) spike fused with CD40 ligand. LNP encapsulation of this CD40L-adjuvanted DNA vaccine with either LNP formulation drastically enhanced antibody responses, enabling neutralization of heterologous Omicron variants. The DNA-LNP formulations provided excellent protection from homologous challenge, reducing viral replication, and preventing histopathological changes in the pulmonary tissues. Moreover, theDNA-LNP vaccines maintained a high level of protection against heterologous Omicron BA.5 challenge despite a reduced neutralizing response. In addition, we observed that DNA-LNP vaccination led to the pulmonary downregulation of interferon signaling, interleukin-12 signaling, and macrophage response pathways following SARS-CoV-2 challenge, shedding some light on the mechanisms underlying the prevention of pulmonary injury. These results highlight the potential combination of molecular adjuvants with LNP-based vaccine delivery to induce greater and broader immune responses capable of preventing inflammatory damage and protecting against emerging variants. These findings could be informative for the future design of both DNA and mRNA vaccines.

Monitoring lung and cerebral oxygenation using near-infrared spectroscopy in preterm infants during kangaroo mother care

Lung function has never been assessed during kangaroo mother care (KMC) in preterm infants. We measured lung (rSO2L) and cerebral (rSO2C) oxygenation by near-infrared spectroscopy (NIRS) in infants born at less than 32 weeks of gestation or weighing ≤ 1500 g during KMC. rSO2L, rSO2C, and pulmonary (FOEL) and cerebral (FOEC) tissue oxygen extraction fraction were measured in 20 preterm infants before, during, and after a 2-h period of KMC at a mean postnatal age of 36 ± 21 days of life. We found that rSO2L, rSO2C, FOEL, and FOEC did not change in our patients. After 120 min of KMC, rSO2L was lower (71.3 ± 1.4 vs. 76.7 ± 4.6%; P = 0.012) in infants with BPD (n = 6; 30%) than in infants without BPD (n = 14 = 60%), while FOEL was higher (0.26 ± 0.02 vs. 0.20 ± 0.05; P = 0.012).Conclusion: Cerebral and lung oxygenation did not change in preterm infants during KMC. A transient decrease in lung oxygenation was offset by the increase in oxygen extraction, but these changes were clinically insignificant. These results confirm the safety of KMC in preterm infants who are in stable clinical conditions.What is Known• Kangaroo mother care (KMC) is widely used to improve the care of preterm newborns since it improves their outcome.• KMC is safe as patients’ vital parameters, are not negatively affected, but lung function has never been directly assessed.What is New• Cerebral and lung oxygenation measured by near-infrared spectroscopy did not change during KMC.• A transient decrease in lung oxygenation compensated for by the increase in oxygen extraction occurred only in infants with BPD, but these changes were clinically insignificant.

The mechanism of action of Botrychium (Thunb.) Sw. for prevention of idiopathic pulmonary fibrosis based on 1H-NMR-based metabolomics.

This study aimed to reveal the anti-fibrotic effects of Botrychium ternatum (Thunb.) Sw. (BT) against idiopathic pulmonary fibrosis (IPF) and to preliminarily analyze its potential mechanism on bleomycin-induced IPF rats. The inhibition of fibrosis progression in vivo was assessed by histopathology combined with biochemical indicators. In addition, the metabolic regulatory mechanism was investigated using 1H-nuclear magnetic resonance-based metabolomics combined with multivariate statistical analysis. Firstly, biochemical analysis revealed that BT notably suppressed the expression of hydroxyproline and transforming growth factor-β1 in the pulmonary tissue. Secondly, Masson's trichrome staining and hematoxylin and eosin showed that BT substantially improved the structure of the damaged lung and significantly inhibited the proliferation of collagen fibers and the deposition of extracellular matrix. Finally, serum metabolomic analysis suggested that BT may exert anti-fibrotic effects by synergistically regulating tyrosine metabolism; phenylalanine, tyrosine and tryptophan biosynthesis; and synthesis and degradation of ketone bodies. Our study not only clarifies the potential anti-fibrotic mechanism of BT against IPF at the metabolic level but also provides a theoretical basis for developing BT as an effective anti-fibrotic agent.

Mitochondrial function in lungs of rats with different susceptibilities to hyperoxia-induced acute lung injury.

Adult rats exposed to hyperoxia (>95% O2) die from respiratory failure in 60-72 h. However, rats preconditioned with >95% O2 for 48 h followed by 24 h in room air acquire tolerance of hyperoxia (H-T), whereas rats preconditioned with 60% O2 for 7 days become more susceptible (H-S). Our objective was to evaluate lung tissue mitochondrial bioenergetics in H-T and H-S rats. Bioenergetics was assessed in mitochondria isolated from lung tissue of H-T, H-S, and control rats. Expressions of complexes involved in oxidative phosphorylation (OxPhos) were measured in lung tissue homogenate. Pulmonary endothelial filtration coefficient (Kf) and tissue mitochondrial membrane potential (Δψm) were evaluated in isolated perfused lungs (IPLs). Results show that ADP-induced state 3 OxPhos capacity (Vmax) decreased in H-S mitochondria but increased in H-T. Δψm repolarization time following ADP-stimulated depolarization increased in H-S mitochondria. Complex I expression decreased in H-T (38%) and H-S (43%) lung homogenate, whereas complex V expression increased (70%) in H-T lung homogenate. Δψm is unchanged in H-S and H-T lungs, but complex II has a larger contribution to Δψm in H-S than H-T lungs. Kf increased in H-S, but not in H-T lungs. For H-T, increased complex V expression and Vmax counter the effect of the decrease in complex I expression on Δψm. A larger complex II contribution to Δψm along with decreased Vmax and increased Kf could make H-S rats more hyperoxia susceptible. Results are clinically relevant since ventilation with ≥60% O2 is often required for extended periods in patients with acute respiratory distress syndrome (ARDS).NEW & NOTEWORTHY We assessed lung tissue mitochondrial bioenergetics in rats with tolerance (H-T) or susceptibility (H-S) to hyperoxia-induced ARDS. Results from studies in isolated mitochondria, tissue homogenate, and isolated perfused lungs show that mitochondrial bioenergetics are differentially altered in H-T and H-S lungs suggesting a potential role for mitochondrial bioenergetics in hyperoxia-induced ARDS. Results are clinically relevant since hyperoxia exposure is a primary therapy for patients with ARDS, and differential sensitivity to hyperoxia surely occurs in humans.

Factors involved in the conversion from video-assisted thoracoscopic surgery decortication to open thoracotomy in non-complicated, non-MDR/XDR stage III tuberculous empyema patients: A retrospective intention-to-treat study

BackgroundThis retrospective intention-to-treat study aims to identify risk factors associated with intraoperative conversion from Video-Assisted Thoracoscopic Surgery (VATS) Decortication to open thoracotomy in patients with Stage III Tuberculous Empyema, specifically focusing on non-Multi-Drug Resistant (MDR)/Extensively Drug-Resistant (XDR) cases. MethodsThe study included 122 patients with non-MDR/XDR tuberculous empyema who were initially scheduled for VATS decortication. Patients were divided into two groups: the Thoracoscopy group (n = 64), who successfully underwent VATS decortication, and the Conversion group (n = 58), who required intraoperative conversion to open thoracotomy. Complex cases were excluded from the study. The analysis focused solely on factors leading to conversion, rather than overall treatment outcomes. ResultsA notable difference was observed in the rate of regular preoperative glucocorticoid utilization between the two cohorts, with the Conversion group exhibiting a lower percentage (46.5 %) in comparison to the Thoracoscopy group (75.0 %). Furthermore, the Thoracoscopy group displayed a significantly reduced frequency of ipsilateral lung abnormalities prior to the surgery (37.5 %), as opposed to that of the Conversion group (65.5 %). Multivariate logistic regression analysis revealed that the regular preoperative glucocorticoid use (odds ratio (OR) = 3.444, 95 % confidence interval (CI): 1.602–7.407) and pre-existing pulmonary lesions (OR = 0.31, 95%CI: 0.150–0.663) were potential influential factors. ConclusionInconsistent preoperative glucocorticoid administration and ipsilateral lung lesions were identified as exacerbating factors leading to the complexity of VATS decortication by causing intraoperative pulmonary tissue contusion or hemorrhage, thus hindering the successful completion of VATS decortication and necessitating a conversion to thoracotomy. Awareness of these factors can aid surgeons in making well-informed decisions regarding the preoperative surgical approach.

Pulmonary delivery of magnolol-loaded nanostructured lipid carriers for COPD treatment

Chronic obstructive pulmonary disease (COPD) is a prevalent lung condition characterized by airflow obstruction, disability, and high mortality rates. Magnolol (MA), known for its anti-inflammatory and antioxidant properties, holds the potential for alleviating COPD symptoms. However, MA faces challenges like poor aqueous solubility and low bioavailability. Herein MA-loaded nanostructured lipid carriers (MA-NLC) were prepared using emulsification and solvent evaporation. These carriers exhibited a particle size of (19.67 ± 0.36) nm, a polydispersity index of (0.21 ± 0.01), and a zeta potential of (−5.18 ± 0.69) mV. The fine particle fraction of MA-NLC was (68.90 ± 0.07)%, indicating minimal lung irritation and enhanced safety. Pulmonary delivery of MA-NLC via nebulizer actively targeted the diseased lung tissues, facilitated slow release, and overcame the challenges of low oral absorption and bioavailability associated with MA. This formulation prolonged the residence time of MA and optimized its therapeutic effect in pulmonary tissues. Upon pulmonary administration, MA-NLC effectively regulated inflammatory and oxidative stress markers in COPD models, demonstrating its potential as a promising therapeutic platform for COPD management.

Evaluation of the Protective Effects of Lugol's Solution in Rats Poisoned with Aluminum Phosphide (Rice Tablets).

Aluminum phosphide (AlP) is the main component of rice tablets (a pesticide), which produces phosphine gas (PH3) when exposed to stomach acid. The most important symptoms of PH3 toxicity include, lethargy, tachycardia, hypotension, and cardiac shock. It was shown that Iodine can chemically react with PH3, and the purpose of this study is to investigate the protective effects of Lugol solution in poisoning with rice tablets. Five doses (12, 15, 21, 23, and 25mg/kg) of AlP were selected, for calculating its lethal dose (LD50). Then, the rats were divided into 4 groups: AlP, Lugol, AlP + Lugol, and Almond oil (as a control). After 4h, the blood pressure and electrocardiogram (ECG) were recorded, and blood samples were obtained for biochemical tests, then liver, lung, kidney, heart, and brain tissues were removed for histopathological examination. The results of the blood pressure showed no significant changes (P > 0.05). In ECG, the PR interval showed a significant decrease in the AlP + Lugol group (P < 0.05). In biochemical tests, LDH, Ca2+, Creatinine, ALP, Mg2+, and K+ represented significant decreases in AlP + Lugol compared to the AlP group (P < 0.05). Also, the administration of Lugol's solution to AlP-poisoned rats resulted in a significant decrease in malondialdehyde levels and a significant increase in catalase activity (P < 0.05). Histopathological evaluation indicates that Lugol improves changes in the lungs, kidneys, brain, and heart. Our results showed that the Lugol solution could reduce tissue damage and oxidative stress in AlP-poisoned rats. We assume that the positive effects of Lugol on pulmonary and cardiac tissues are due to its ability to react directly with PH3.

Anti-CCL2 therapy reduces oxygen toxicity to the immature lung

Oxygen toxicity constitutes a key contributor to bronchopulmonary dysplasia (BPD). Critical step in the pathogenesis of BPD is the inflammatory response in the immature lung with the release of pro-inflammatory cytokines and the influx of innate immune cells. Identification of efficient therapies to alleviate the inflammatory response remains an unmet research priority. First, we studied macrophage and neutrophil profiles in tracheal aspirates of n = 103 preterm infants <29 weeks´ gestation requiring mechanical ventilation. While no differences were present at birth, a higher fraction of macrophages, the predominance of the CD14+CD16+ subtype on day 5 of life was associated with moderate/severe BPD. Newborn CCL-2−/− mice insufficient in pulmonary macrophage recruitment had a reduced influx of neutrophils, lower apoptosis induction in the pulmonary tissue and better-preserved lung morphometry with higher counts of type II cells, mesenchymal stem cells and vascular endothelial cells when exposed to hyperoxia for 7 days. To study the benefit of a targeted approach to prevent the pulmonary influx of macrophages, wildtype mice were repeatedly treated with CCL-2 blocking antibodies while exposed to hyperoxia for 7 days. Congruent with the results in CCL-2−/− animals, the therapeutic intervention reduced the pulmonary inflammatory response, attenuated cell death in the lung tissue and better-preserved lung morphometry. Overall, our preclinical and clinical datasets document the predominant role of macrophage recruitment to the pathogenesis of BPD and establish the abrogation of CCL-2 function as novel approach to protect the immature lung from hyperoxic injury.

Omarigliptin/rosinidin combination ameliorates cyclophosphamide-induced lung toxicity in rats: The interaction between glucagon-like peptide-1, TXNIP/NLRP3 inflammasome signaling, and PI3K/Akt/FoxO1 axis

Cyclophosphamide is an anti-neoplastic drug that has shown competence in the management of a broad range of malignant tumors. In addition, it represents a keystone agent for management of immunological conditions. Despite these unique properties, induction of lung toxicity may limit its clinical use. Omarigliptin is one of the dipeptidyl peptidase-4 inhibitors that has proven efficacy in management of diabetes mellitus. Rosinidin is an anthocyanidin flavonoid that exhibited promising results in management of diseases characterized by oxidative stress, inflammation, and apoptosis. The present work investigated the possible effects of omarigliptin with or without rosinidin on cyclophosphamide-induced lung toxicity with an exploration of the molecular mechanisms that contribute to these effects. In a rodent model of cyclophosphamide elicited lung toxicity, the potential efficacy of omarigliptin with or without rosinidin was investigated at both the biochemical and the histopathological levels. Both omarigliptin and rosinidin exhibited a synergistic ability to augment the tissue antioxidant defenses, mitigate the inflammatory pathways, restore glucagon-like peptide-1 levels, modulate high mobility group box 1 (HMGB1)/receptors of advanced glycation end products (RAGE)/nuclear factor kappa B (NF-κB) axis, downregulate the fibrogenic mediators, and create a balance between the pathways involved in apoptosis and the autophagy signals in the pulmonary tissues. In conclusion, omarigliptin/rosinidin combination may be introduced as a novel therapeutic modality that attenuates the different forms of lung toxicities induced by cyclophosphamide.

The suppressive role of NLRP6 in host defense against Streptococcus suis infection

Streptococcus suis (S. suis) disease is a prevalent zoonotic infectious threat that elicits a systemic inflammatory response in both swine and humans, frequently culminating in high mortality rates. The excessive inflammation triggered by S. suis infection can precipitate tissue damage and sudden death; however, a comprehensive strategy to mitigate this inflammatory response remains elusive. Our study examines the role of NLRP6 in S. suis infection, with a particular focus on its involvement in pathogen regulation. A marked upregulation of NLRP6 was observed in peritoneal macrophages post-infection with S. suis SC19 strain, consequently activating the NLRP6 inflammasome. Furthermore, SC19 infection was found to augment the secretion of pro-inflammatory cytokines IL-1β via NLRP6 activation, while NLRP6 deficiency mitigates the invasion and adhesion of SC19 to macrophages. In vivo models revealed that NLRP6 deletion enhanced survival rates of SC19-infected mice, alongside a reduction in tissue bacterial load and inflammatory cytokine levels. NLRP6-/- mice were shown to exhibit attenuated inflammatory responses in pulmonary, hepatic, and splenic tissues post-SC19 infection, as evidenced by lower inflammation scores. Flow cytometry analyses further substantiated that NLRP6 is involved in modulating macrophage and neutrophil recruitment during infection. Our findings suggest that NLRP6 negatively regulates host resistance against S. suis infection; its absence results in reduced mortality, bacterial colonization, and a milder inflammatory response. Elucidating the mechanism of NLRP6 in S. suis-induced inflammation provides novel insights and theoretical underpinnings for the prophylaxis and therapeutics of S. suis diseases.

Altered ontogeny and transcriptomic signatures of tissue-resident pulmonary interstitial macrophages ameliorate allergic airway hyperresponsiveness.

Environmental exposures and experimental manipulations can alter the ontogenetic composition of tissue-resident macrophages. However, the impact of these alterations on subsequent immune responses, particularly in allergic airway diseases, remains poorly understood. This study aims to elucidate the significance of modified macrophage ontogeny resulting from environmental exposures on allergic airway responses to house dust mite (HDM) allergen. We utilized embryonic lineage labeling to delineate the ontogenetic profile of tissue-resident macrophages at baseline and following the resolution of repeated lipopolysaccharide (LPS)-induced lung injury. We investigated differences in house dust mite (HDM)-induced allergy to assess the influence of macrophage ontogeny on allergic airway responses. Additionally, we employed single-cell RNA sequencing (scRNAseq) and immunofluorescent staining to characterize the pulmonary macrophage composition, associated pathways, and tissue localization. Our findings demonstrate that the ontogeny of homeostatic alveolar and interstitial macrophages is altered after the resolution from repeated LPS-induced lung injury, leading to the replacement of embryonic-derived by bone marrow-derived macrophages. This shift in macrophage ontogeny is associated with reduced HDM-induced allergic airway responses. Through scRNAseq and immunofluorescent staining, we identified a distinct subset of resident-derived interstitial macrophages expressing genes associated with allergic airway diseases, localized adjacent to terminal bronchi, and diminished by prior LPS exposure. These results suggest a pivotal role for pulmonary macrophage ontogeny in modulating allergic airway responses. Moreover, our findings highlight the implications of prior environmental exposures in shaping future immune responses and influencing the development of allergies. By elucidating the mechanisms underlying these phenomena, this study provides valuable insights into potential therapeutic targets for allergic airway diseases and avenues for further research into immune modulation and allergic disease prevention.