Mechanisms of bleomycin-induced lung damage

Ziziphus spina-christi L. extract attenuates bleomycin-induced lung fibrosis in mice via regulating TGF-β1/SMAD pathway: LC-MS/MS Metabolic profiling, chemical composition, and histology studies

Ancient Egyptians (including Bedouins and Nubians) have long utilized Ziziphus spina-christi (L.), a traditional Arabian medicinal herb, to alleviate swellings and inflammatory disorders. It is also mentioned in Christian and Muslim traditions. Ziziphus spina-christi L. (Family: Rhamnaceae) is a plentiful source of polyphenols, revealing free radical scavenging, antioxidant, metal chelating, cytotoxic, and anti-inflammatory activities. Herein, different classes of the existing bioactive metabolites in Z. spina-christi L. were detected using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the first time. The study also aimed to assess the anti-inflammatory and antifibrotic properties of Z. spina-christi L. extract against bleomycin-induced lung fibrosis in an experimental mouse model. 32 male Swiss Albino mice were assigned into 4 groups; the first and second were the normal control group and the bleomycin positive control (single 2.5 U/kg bleomycin intratracheal dose). The third and fourth groups received 100 and 200 mg/kg/day Z. spina-christi L. extract orally for 3 weeks, 2 weeks before bleomycin, and 1 week after. The bioactive metabolites in Z. spina-christi L. extract were identified as phenolic acids, catechins, flavonoids, chalcones, stilbenes, triterpenoid acids, saponins, and sterols. The contents of total phenolic compounds and flavonoids were found to be 196.62 mg GAE/gm and 33.29 mg QE/gm, respectively. In the experimental study, histopathological examination revealed that lung fibrosis was attenuated in both Z. spina-christi L.- treated groups. Z. spina-christi L. extract downregulated the expression of nuclear factor kappa B (NF-κB) p65 and decreased levels of the inflammatory markers tumor necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and c-Jun N-terminal kinase (JNK) in lung tissue. Z. spina-christi L. also downregulated the expression of the fibrotic parameters collagen-1, alpha-smooth muscle actin (α-SMA), transforming growth factor-beta 1 (TGF-β1), matrix metalloproteinase-9 (MMP-9) and SMAD3, with upregulation of the antifibrotic SMAD7 in lung tissue. Overall, the present study suggests a potential protective effect of Z. spina-christi L. extract against bleomycin-induced lung fibrosis through regulation of the TGF-β1/SMAD pathway.

An ATMND/SGI based three-way junction ratiometric fluorescent probe for rapid and sensitive detection of bleomycin

In this work, we developed a rapid and sensitive label-free ratiometric fluorescent (FL) probe for the detection of bleomycin (BLM). The probe consists of a DNA sequence (D6) and two fluorophore groups, 2-amino-5,6,7-trimethyl-1,8-naphthalene (ATMND) and SYBR Green I (SGI). The D6 sequence could be folded into a three-way junction structure containing a C-C mismatch position in the junction pocket. The unique "Y" structure not only could entrap ATMND in the mismatch pocket with high affinity, leading to FL quenching at 408 nm, but also embed SGI in the grooves of the double-stranded portion, resulting in FL enhancement at 530 nm. In the presence of BLM-Fe(II), the "Y" structure of D6 was destroyed due to the specific cleavage of the BLM recognition site, the 5'-GT-3' site in D6. This caused the release of ATMND and SGI and thus the ratiometric signal change of FL enhancement by ATMND and FL quenching by SGI. Under optimal conditions, the ratiometric probe exhibited a linear correlation between the intensity ratio of F408/F530 and the concentration of BLM in the range of 0.5-1000 nM, with a detection limit of 0.2 nM. In addition, the probe was applied to detect BLM in human serum samples with satisfactory results, indicating its good clinical application potential.

IL-22 Binding Protein Controls IL-22-Driven Bleomycin-Induced Lung Injury

The high mortality rates of acute lung injury and acute respiratory distress syndrome challenge the field to identify biomarkers and factors that can be exploited for therapeutic approaches. IL-22 is a cytokine that has antibacterial and reparative properties in the lung. However, it also can exacerbate inflammation and requires tight control by the extracellular inhibitory protein known as IL-22 binding protein (IL-22BP) (Il22ra2). This study showed the necessity of IL-22BP in controlling and preventing acute lung injury using IL-22BP knockout mice (Il22ra2-/-) in the bleomycin model of acute lung injury/acute respiratory distress syndrome. Il22ra2-/- mice had greater sensitivity (weight loss and death) and pulmonary inflammation in the acute phase (first 7 days) of the injury compared with wild-type C57Bl/6 controls. The inflammation was driven by excess IL-22 production, inducing the influx of pathogenic IL-17A+ γδ T cells to the lung. Interestingly, this inflammation was initiated in part by the noncanonical IL-22 signaling to macrophages, which express the IL-22 receptor (Il22ra1) in vivo after bleomycin challenge. This study further showed that IL-22 receptor alpha-1+ macrophages can be stimulated by IL-22 to produce a number of IL-17-inducing cytokines such as IL-1β, IL-6, and transforming growth factor-β1. Together, the results suggest that IL-22BP prevents IL-22 signaling to macrophages and reduces bleomycin-mediated lung injury.

Electrochemotherapy in Aggressive Hemangioma of the Spine: A Case Series and Narrative Literature Review

(1) Background: this case series and literature review aims to evaluate the efficacy and safety of electrochemotherapy in the management of aggressive spinal hemangiomas, presenting two distinct cases. (2) Methods: we present two cases of spinal aggressive hemangioma which were refractory to conventional treatments and underwent electrochemotherapy. Case 1 involves a 50-year-old female who presented with an aggressive spinal hemangioma of L1, who previously underwent various treatments including surgery, radio-chemotherapy, and arterial embolization. Case 2 describes a 16-year-old female with a T12 vertebral hemangioma, previously treated with surgery and stabilization, who faced limitations in treatment options due to her young age and the location of the hemangioma. (3) Results: in Case 1, electrochemotherapy with bleomycin was administered following the failure of previous treatments and resulted in the reduction of the lesion size and improvement in clinical symptoms. In Case 2, electrochemotherapy was chosen due to the risks associated with other treatments and was completed without any adverse events. Both cases demonstrated the potential of electrochemotherapy as a viable treatment option for spinal hemangiomas, especially in complex or recurrent cases. (4) Conclusions: electrochemotherapy with bleomycin is a promising treatment for aggressive spinal hemangiomas when conventional therapies are not feasible or have failed. Further research is needed to establish definitive protocols and long-term outcomes of electrochemotherapy in spinal hemangioma management.

A cost-effective, "mix & act" G-quadruplex/Cu (II) metal-nanozyme-based ratiometric fluorescent platform for highly sensitive and selective cysteine/bleomycin detection and multilevel contrary logic computing

Versatile nanozymes with fascinating catalytic properties provide inspiring and effective options for biosensing and pharmaceutical analysis. Herein, we report the first nanozyme-based ratiometric fluorescent platform for cysteine (Cys) and bleomycin (BLM) detection by harnessing the cost-effective and "mix & act" G-quadruplex/Cu(II) (G4/Cu) metal-nanozyme with satisfactory peroxidase-like activity, which was fully proven by circular dichroism (CD), electron paramagnetic resonance (EPR) spectra and reactive oxygen species (ROS) scavenging experiments. Based on the catalytic oxidation of G4/Cu metal-nanozyme toward two fluorescent substrates (Amplex Ultrared, AU; Scopoletin, Sc) with opposite responses in the presence of H2O2, and the specific interaction between Cu2+ and targets, we achieved the highly sensitive detection of Cys and BLM. Through recording the fluorescence changes of AU (emission at 590 nm, F590) and Sc (emission at 465 nm, F465), we obtained good linear relationships between ratiometric fluorescence values (F590/F465) and variable contents of targets, resulting in the competitive LODs of Cys (6.7 nM) and BLM (10 nM), respectively. Moreover, this platform presented high selectivity (without the need for masking agent) and acceptable performance in human serum samples. Furthermore, a library of DNA contrary logic pairs (CLPs) and multilevel concatenated circuits were fabricated based on the reverse dual-output of the above platform, enriching the building blocks of biocomputing. This work not only enlightened the design of affordable, "mix & act" type nanozyme-based ratiometric biosensors with high reliability, but also facilitated the pluralistic application of nucleic acid-templated nanozymes to innovative biocomputing.

Direct assessment of nitrative stress in lipid environments: Applications of a designer lipid-based biosensor for peroxynitrite

Lipid membranes and lipid-rich organelles are targets of peroxynitrite (ONOO-), a highly reactive species generated under nitrative stress. We report a membrane-localized phospholipid (DPPC-TC-ONOO-) that allows the detection of ONOO- in diverse lipid environments: biomimetic vesicles, mammalian cell compartments, and within the lung lining. DPPC-TC-ONOO- and POPC self-assemble to membrane vesicles that fluorogenically and selectively respond to ONOO-. DPPC-TC-ONOO-, delivered through lipid nanoparticles, allowed for ONOO- detection in the endoplasmic reticulum upon cytokine-induced nitrative stress in live mammalian cells. It also responded to ONOO- within lung tissue murine models upon acute lung injury. We observed nitrative stress around bronchioles in precision cut lung slices exposed to nitrogen mustard and in pulmonary macrophages following intratracheal bleomycin challenge. Results showed that DPPC-TC-ONOO- functions specifically toward iNOS, a key enzyme modulating nitrative stress, and offers significant advantages over its hydrophilic analog in terms of localization and signal generation.

Recent advances in BCRP-induced breast cancer resistance treatment with marine-based natural products

Breast cancer is the prominent cause of cancer-related death in women globally in terms of incidence and mortality. Despite, recent advances in the management of breast cancer, there are still a lot of cases of resistance to medicines, which is currently one of the biggest problems faced by researchers across the globe. Out of several mechanisms, breast cancer resistance protein (BCRP) arbitrated drug resistance is a major concern. Hormonal, cytotoxic and immunotherapeutic drugs are used in the systemic therapy of breast cancer. It is vital to choose drugs based on the clinical and molecular attributes of the tumor to provide better treatment with greater efficacy and minimal harm. Given the aforementioned necessity, the use of marine flora in treating breast cancer cannot be neglected. The scientists also stressed the value of marine-derived goods in avoiding breast cancer resistance. Future research into the identification of anticancer drugs will heavily draw upon the marine environment's ample supply of marine-derived natural products (MNPs), which have a wide range of biological functions. Cell cycle arrest, induction of apoptosis and anti-angiogenic, anti-proliferative and anti-metastasis actions are all part of their processes. The overview of breast cancer, the mechanisms underlying its resistance, recent clinical trials based on marine-derived products in breast cancer and the use of marine products in the treatment of breast cancer are highlighted in this paper. Moreover, the authors also emphasised the importance of marine-derived products in preventing breast cancer resistance.

Response of PRIMPOL-Knockout Human Lung Adenocarcinoma A549 Cells to Genotoxic Stress

Human DNA primase/polymerase PrimPol synthesizes DNA primers de novo after replication fork stalling at the sites of DNA damage, thus contributing to the DNA damage tolerance. The role of PrimPol in response to the different types of DNA damage is poorly understood. We knocked out the PRIMPOL gene in the lung carcinoma A549 cell line and characterized the response of the obtained cells to the DNA damage caused by hydrogen peroxide, methyl methanesulfonate (MMS), cisplatin, bleomycin, and ionizing radiation. The PRIMPOL knockout reduced the number of proliferating cells and cells in the G2 phase after treatment with MMS and caused a more pronounced delay of the S phase in the cisplatin-treated cells. Ionizing radiation at a dose of 10 Gy significantly increased the content of apoptotic cells among the PRIMPOL-deficient cells, while the proportion of cells undergoing necroptosis increased in both parental and knockout cells at any radiation dose. The viability of PRIMPOL-deficient cells upon the hydrogen peroxide-induced oxidative stress increased compared to the control cells, as determined by the methyl tetrazolium (MTT) assay. The obtained data indicate the involvement of PRIMPOL in the modulation of adaptive cell response to various types of genotoxic stress.

Sesamol attenuates bleomycin-induced pulmonary toxicity and fibrosis in experimental animals

Sesamol, a lignan obtained from roasted seeds of Sesamum indicum, has high antioxidant and anti-inflammatory activity. In this study, we have investigated the effect of sesamol on Bleomycin (BLM) induced pulmonary toxicity as well as fibrosis in Wistar rats. Lung toxicity was induced by administration of BLM, 0.015 U/g ip, twice weekly for 28 days whereas lung fibrosis was induced by BLM, 0.015 U/g ip, every 5th day for 49 days. Sesamol administration was started 7 days before first dose of BLM in both the models. It was observed that sesamol 50 mg/kg most effectively attenuated pulmonary toxicity by reducing oxidative stress, inflammation and apoptosis. This dose was further evaluated for its anti-fibrotic effect. It was observed that there was a significant reduction in fibrosis. Lung collagen content was markedly reduced. Furthermore, expression of pro-fibrotic proteins, TGF-β/SMAD and α-SMA, was reduced and that of anti-fibrotic protein, AMPK, was markedly increased. Even though the combination of sesamol with pirfenidone exhibited no additional protection than either drug alone, it is evident from our study that our test drug, sesamol is comparable in efficacy to pirfenidone. Thus, sesamol has promising therapeutic potential in treatment of pulmonary toxicity and fibrosis.

GATA1-defective immune-megakaryocytes as possible drivers of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disorder with limited therapeutic options. Insufficient understanding of driver mutations and poor fidelity of currently available animal models has limited the development of effective therapies. Since GATA1 deficient megakaryocytes sustain myelofibrosis, we hypothesized that they may also induce fibrosis in lungs. We discovered that lungs from IPF patients and Gata1low mice contain numerous GATA1negative immune-poised megakaryocytes that, in mice, have defective RNA-seq profiling and increased TGF-β1, CXCL1 and P-selectin content. With age, Gata1low mice develop fibrosis in lungs. Development of lung fibrosis in this model is prevented by P-selectin deletion and rescued by P-selectin, TGF-β1 or CXCL1 inhibition. Mechanistically, P-selectin inhibition decreases TGF-β1 and CXCL1 content and increases GATA1positive megakaryocytes while TGF-β1 or CXCL1 inhibition decreased CXCL1 only. In conclusion, Gata1low mice are a novel genetic-driven model for IPF and provide a link between abnormal immune-megakaryocytes and lung fibrosis.

Jingfang Granule alleviates bleomycin-induced acute lung injury via CD200-CD200R immunoregulatory pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Jingfang granules (JF), one famous traditional Chinese formula in "She Sheng Zhong Miao Fang" written by Shi-Che Zhang during the Ming Dynasty era, has been widely used to prevent epidemic diseases in history and now was recommended for the treatment of coronavirus disease 2019 (COVID-19) in China. However, the roles of JF against acute lung injury and its mechanisms remain unclear.

AIM OF THE STUDY

Acute lung injury (ALI) and its progressive acute respiratory distress syndrome (ARDS) are a continuum of lung inflammatory disease with high morbidity and mortality in clinic, especially in COVID-19 patients. The present study aims to investigate the effect of JF on ALI and clarify its underlying mechanisms for clinical application in COVID-19 control.

METHODS

Bleomycin-induced ALI mice were given oral gavage daily for seven days with or without Jingfang granules (2, 4 g/kg). The body weight, lung wet/dry weight ratios, lung appearance and tissue histopathology were evaluated. Quantitative real-time PCR, biochemical bronchoalveolar lavage fluids analysis was used to determine the gene expression of proinflammation factor and infiltrated inflammatory cells in lung. Immunofluorescence image and western blot were used to detect the markers of alveolar macrophages (AMs), endothelial cell apoptosis and changes of CD200-CD200R pathway.

RESULTS

Firstly, histopathological analysis showed that JF significantly attenuated pulmonary injury and inflammatory response in ALI mice. Then, cytokine detection, inflammatory cells assay, and JNKs and p38 pathway analysis indicated that the recruitment and activation of alveolar macrophages was the main reason to cause ALI and JF could reverse this variation. Next, immunofluorescence staining and TUNEL assay showed that JF upregulated the expression of CD200 and suppressed the apoptosis of alveolar endothelial cells. Finally, double immunofluorescence staining of CD200 and CD11c indicated that the seriously damaged tissue had the lower CD200 while more AMs infiltration, which was confirmed by RT-PCR analysis of CD200/CD200R.

CONCLUSIONS

Jingfang granules can protect lung from acu te injury and mitigate the recruitment and overactive AMs-induced inflammation via CD200-CD200R immunoregulatory signal axis, which will provide an experimental basis for Jingfang granules clinical applications in COVID-19.

Amygdalin epimers exert discrepant anti-pulmonary fibrosis activity via inhibiting TGF-β1/Smad2/3 pathway

Idiopathic pulmonary fibrosis (IPF) represents a chronic and progressive tissue repair response that leads to irreversible scarring and lung remodelling. The decoction of bitter almond usually contains amygdalin epimers in traditional clinical application for lung disease. To reveal the differences of cytotoxicity and antifibrotic effect between amygdalin epimers, and potential mechanism is also explored. The cytotoxicity of amygdalin epimers were evaluated with MRC-5 cells in vitro. Their antifibrotic activities were evaluated in bleomycin-induced C57BL/6 mice and TGF-β1-induced MRC-5 cells. Here we demonstrated that L-amygdalin is more toxic of the amygdalin epimers in MRC-5 cells, and D-amygdalin is more effective in anti-pulmonary fibrosis among the amygdalin epimers in bleomycin-induced C57BL/6 mice. Herein, it was observed that D-amygdalin had a stronger inhibitory effect on inflammation than L-amygdalin, and had similar results in inhibiting the mRNA and protein expression levels of fibrosis-related biomarkers. The mechanism of anti-pulmonary fibrosis showed that amygdalin epimers suppressing expression of phosphorylation of Smads2/3, which implying deactivation of the TGF-β1induced Smads2/3 signal pathway. This study evaluates the amygdalin epimers cytotoxicity and antifibrotic effect, and its mechanisms were related to the TGF-β1/Smads2/3 signal pathway. It provides a reference for clinical safety and effectiveness of amygdalin epimers.

Insights on the mechanism of bleomycin to induce lung injury and associated in vivo models: A review

Acute lung injury leads to the development of chronic conditions such as idiopathic pulmonary fibrosis (IPF), chronic obstructive pulmonary disease (COPD), asthma as well as alveolar sarcoma. Various investigations are being performed worldwide to understand the pathophysiology of these diseases, develop novel bioactive compounds and inhibitors to target the ailment. Generally, in vivo models are used to understand the disease outcome and therapeutic suppressing effects for which the animals are chemically or physically induced to mimic the onset of definite disease conditions. Amongst the chemical inducing agents, Bleomycin (BLM) is the most successful inducer. It is reported to target various receptors and activate inflammatory pathways, cellular apoptosis, epithelial mesenchymal transition leading to the release of inflammatory cytokines, and proteases. Mice is one of the most widely used animal model for BLM induced pulmonary associated studies apart from rat, rabbit, sheep, pig, and monkey. Although, there is considerable variation amongst in vivo studies for BLM induction which suggests a detailed study on the same to understand the mechanism of action of BLM at molecular level. Hence, herein we have reviewed various chemical inducers, mechanism of action of BLM in inducing lung injury in vivo, its advantages and disadvantages. Further, we have also discussed the rationale behind various in vivo models and recent development in BLM induction for various animals.

The Role of Sphingolipids in Regulating Vascular Permeability in Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a disease that causes scarring and fibrotic transformation of the lung parenchyma, resulting in the progressive loss of respiratory function and, often, death. Current treatments that target profibrotic factors can slow the rate of progression but are unable to ultimately stop it. In the past decade, many studies have shown that increased vascular permeability may be both a predictive and perpetuating factor in fibrogenesis. Consequently, there is a search for therapeutic targets to try and modulate vascular permeability in fibrotic lungs. One such class of targets that show great promise is sphingolipids. Sphingolipids are common in cell membranes and are increasingly recognized as critical to many cell signaling pathways, including those that affect the integrity of the vascular endothelial barrier. In this focused review we look at sphingolipids, particularly the sphingosine-1-phosphate (S1P) axis and its effects on vascular permeability, and how those effects may affect the pathogenesis of IPF. We further examine existing S1P modulators and their potential efficacy as therapeutics for IPF.

High-Frequency Electroporation and Chemotherapy for the Treatment of Cutaneous Malignancies: Evaluation of Early Clinical Response

High-frequency electroporation (HF-EP) with chemotherapy is a novel therapy proposed for both curative and palliative treatment of cutaneous malignancies. The use of high-frequency biphasic pulses is thought to reduce the painful muscle contractions associated with traditional electrochemotherapy (ECT), allowing treatment administration under local anaesthesia. This proof-of-concept study investigated the efficacy and tolerability of HF-EP protocols on a variety of cutaneous malignancies. A total of 97 lesions of five different histological subtypes were treated across 25 patients. At 12 weeks post-treatment, a 91.3% overall lesion response rate was observed (complete response: 79%; partial response: 12.3%), with excellent intraprocedural patient tolerability under local anaesthetic. HF-EP with chemotherapy shows promising results regarding tumour response rates for cutaneous malignancies of varying histological subtypes when compared to traditional ECT protocols. Improved patient tolerability is important, increasing the possibility of treatment delivery under local anaesthesia and potentially broadening the treatment envelope for patients with cutaneous malignancies.

Inhibition of Fatty Acid Amide Hydrolase (FAAH) Regulates NF-kb Pathways Reducing Bleomycin-Induced Chronic Lung Inflammation and Pulmonary Fibrosis

The deadly interstitial lung condition known as idiopathic pulmonary fibrosis (IPF) worsens over time and for no apparent reason. The traditional therapy approaches for IPF, which include corticosteroids and immunomodulatory drugs, are often ineffective and can have noticeable side effects. The endocannabinoids are hydrolyzed by a membrane protein called fatty acid amide hydrolase (FAAH). Increasing endogenous levels of endocannabinoid by pharmacologically inhibiting FAAH results in numerous analgesic advantages in a variety of experimental models for pre-clinical pain and inflammation. In our study, we mimicked IPF by administering intratracheal bleomycin, and we administered oral URB878 at a dose of 5 mg/kg. The histological changes, cell infiltration, pro-inflammatory cytokine production, inflammation, and nitrosative stress caused by bleomycin were all reduced by URB878. Our data clearly demonstrate for the first time that the inhibition of FAAH activity was able to counteract not only the histological alteration bleomycin-induced but also the cascade of related inflammatory events.

Regulating the cell shift of endothelial cell-like myofibroblasts in pulmonary fibrosis

Pulmonary fibrosis is a common and severe fibrotic lung disease with high morbidity and mortality. Recent studies have reported a large number of unwanted myofibroblasts appearing in pulmonary fibrosis, and shown that the sustained activation of myofibroblasts is essential for unremitting interstitial fibrogenesis. However, the origin of these myofibroblasts remains poorly understood. Here, we create new mouse models of pulmonary fibrosis and identify a previously unknown population of endothelial cell (EC)-like myofibroblasts in normal lung tissue. We show that these EC-like myofibroblasts significantly contribute myofibroblasts to pulmonary fibrosis, which is confirmed by single-cell RNA sequencing of human pulmonary fibrosis. Using the transcriptional profiles, we identified a small molecule that redirects the differentiation of EC-like myofibroblasts and reduces pulmonary fibrosis in our mouse models. Our study reveals the mechanistic underpinnings of the differentiation of EC-like myofibroblasts in pulmonary fibrosis and may provide new strategies for therapeutic interventions.

Cross-sectional and Longitudinal Associations Between Propylene Oxide Exposure and Lung Function Among Chinese Community Residents: Roles of Oxidative DNA Damage, Lipid Peroxidation, and Protein Carbonylation

BACKGROUND

Toxicologic studies have reported propylene oxide (PO) exposure may harm the respiratory system, but the association between PO exposure and lung function and potential mechanism remains unclear.

RESEARCH QUESTION

What is the association between PO exposure and lung function and potential mediating mechanism?

STUDY DESIGN AND METHODS

Urinary PO metabolite [N-Acetyl-S-(2-hydroxypropyl)-L-cysteine (2HPMA)] as PO internal exposure biomarker and lung function were measured for 3,692 community residents at baseline and repeated at 3-year follow up. Cross-sectional and longitudinal associations between urinary 2HPMA and lung function were assessed by linear mixed model. Urinary 8-hydroxy-deoxyguanosine, urinary 8-iso-prostaglandin-F2α, and plasma protein carbonyls as biomarkers of oxidative DNA damage, lipid peroxidation, and protein carbonylation, respectively, were measured for all participants to explore their potential roles in 2HPMA-associated lung function decline by mediation analysis.

RESULTS

After adjustment for potential covariates, each threefold increase in urinary 2HPMA was cross sectionally associated with a 26.18 mL (95% CI, -50.55 to -1.81) and a 21.83 mL (95% CI, -42.71 to -0.95) decrease in FVC and FEV1, respectively, at baseline (all P < .05). After 3 years of follow up, 2HPMA was observed to be longitudinally associated with FEV1/FVC decline. No significant interaction effect of smoking or passive smoking was observed (Pinteraction > .05), and the associations between 2HPMA and lung function indexes were persistent among participants who were not smoking and those who were not passive smoking in both baseline and follow-up evaluations. We observed urinary 8-hydroxy-deoxyguanosine partially mediated the associations of 2HPMA with FVC (mediation proportion, 5.48%) and FEV1 (mediation proportion, 6.81%), and plasma protein carbonyl partially mediated the association between 2HPMA and FEV1 (mediation proportion, 3.44%).

INTERPRETATION

PO exposure was associated with lung function decline among community residents, and oxidative DNA damage and protein carbonylation partially mediated PO exposure-associated lung function decline. Further attention on respiratory damage caused by PO exposure is warranted.

Fu-Zheng-Tong-Luo formula promotes autophagy and alleviates idiopathic pulmonary fibrosis by controlling the Janus kinase 2/signal transducer and activator of transcription 3 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Fu-Zheng-Tong-Luo (FZTL) formula is a Chinese herbal prescription which is used to treat idiopathic pulmonary fibrosis (IPF). We previously reported that the FZTL formula could improve IPF injury in rats; however, the mechanism remains unelucidated.

AIM OF THE STUDY

To elucidate the effects and mechanisms of the FZTL formula on IPF.

MATERIALS AND METHODS

The bleomycin-induced pulmonary fibrosis rat model and transforming growth factor-β-induced lung fibroblast model were used. Histological changes and fibrosis formation were detected in the rat model after treatment with the FZTL formula. Furthermore, the effects of the FZTL formula on autophagy and lung fibroblast activation were determined. Moreover, the mechanism of FZTL was explored using transcriptomics analysis.

RESULTS

We observed that FZTL alleviated IPF injury in rats and inhibited inflammatory responses and fibrosis formation in rats. Moreover, it promoted autophagy and inhibited lung fibroblast activation in vitro. Transcriptomics analysis revealed that FZTL regulates the Janus kinase 2 (JAK)/signal transducer and activator of the transcription 3 (STAT) signaling pathway. The JAK2/STAT3 signaling activator interleukin 6 inhibited the anti-fibroblast activation effect of the FZTL formula. Combined treatment with the JAK2 inhibitor (AZD1480) and autophagy inhibitor (3-methyladenine) did not enhance the antifibrotic effect of FZTL.

CONCLUSIONS

The FZTL formula can inhibit IPF injury and lung fibroblast activation. Its effects are mediated via the JAK2/STAT3 signaling pathway. The FZTL formula may be a potential complementary therapy for pulmonary fibrosis.

A Bridge to Nowhere: Enabling Autonomy in a Case of Failed ECMO Rescue of Bleomycin-Induced Pulmonary Toxicity

Extracorporeal membrane oxygenation (ECMO) can be a life-saving intervention in cases of potentially reversible refractory respiratory failure. One such indication can be bleomycin-induced lung injury. However, in some cases, the injury can be so severe that it becomes irreversible and creates complex medical decisions regarding life support and the continuation of care when no additional therapeutic options are feasible, particularly in cases of patients who were young and fully functional prior to an acute illness. In cases of full pulmonary replacement with mechanical support and the degree of functionality that can be attained utilizing modalities such as ECMO can obscure the true severity of illness and make end-of-life decisions significantly harder for families and caregivers.

A comprehensive network map of IL-17A signaling pathway

Interleukin-17A (IL-17A) is one of the member of IL-17 family consisting of other five members (IL-17B to IL-17F). The Gamma delta (γδ) T cells and T helper 17 (Th17) cells are the major producers of IL-17A. Aberrant signaling by IL-17A has been implicated in the pathogenesis of several autoimmune diseases including idiopathic pulmonary fibrosis, acute lung injury, chronic airway diseases, and cancer. Activation of the IL-17A/IL-17 receptor A (IL-17RA) system regulates phosphoinositide 3-kinase/AKT serine/threonine kinase/mammalian target of rapamycin (PI3K/AKT/mTOR), mitogen-activated protein kinases (MAPKs) and activation of nuclear factor-κB (NF-κB) mediated signaling pathways. The IL-17RA activation orchestrates multiple downstream signaling cascades resulting in the release of pro-inflammatory cytokines such as interleukins (IL)-1β, IL-6, and IL-8, chemokines (C-X-C motif) and promotes neutrophil-mediated immune response. Considering the biomedical importance of IL-17A, we developed a pathway resource of signaling events mediated by IL-17A/IL-17RA in this study. The curation of literature data pertaining to the IL-17A system was performed manually by the NetPath criteria. Using data mined from the published literature, we describe an integrated pathway reaction map of IL-17A/IL-17RA consisting of 114 proteins and 68 reactions. That includes detailed information on IL-17A/IL-17RA mediated signaling events of 9 activation/inhibition events, 17 catalysis events, 3 molecular association events, 68 gene regulation events, 109 protein expression events, and 6 protein translocation events. The IL-17A signaling pathway map data is made freely accessible through the WikiPathways Database ( https://www.wikipathways.org/index.php/Pathway : WP5242).

Anti-inflammatory actions of Pentosan polysulfate sodium in a mouse model of influenza virus A/PR8/34-induced pulmonary inflammation

Introduction

There is an unmet medical need for effective anti-inflammatory agents for the treatment of acute and post-acute lung inflammation caused by respiratory viruses. The semi-synthetic polysaccharide, Pentosan polysulfate sodium (PPS), an inhibitor of NF-kB activation, was investigated for its systemic and local anti-inflammatory effects in a mouse model of influenza virus A/PR8/1934 (PR8 strain) mediated infection.

Methods

Immunocompetent C57BL/6J mice were infected intranasally with a sublethal dose of PR8 and treated subcutaneously with 3 or 6 mg/kg PPS or vehicle. Disease was monitored and tissues were collected at the acute (8 days post-infection; dpi) or post-acute (21 dpi) phase of disease to assess the effect of PPS on PR8-induced pathology.

Results

In the acute phase of PR8 infection, PPS treatment was associated with a reduction in weight loss and improvement in oxygen saturation when compared to vehicle-treated mice. Associated with these clinical improvements, PPS treatment showed a significant retention in the numbers of protective SiglecF+ resident alveolar macrophages, despite uneventful changes in pulmonary leukocyte infiltrates assessed by flow cytometry. PPS treatment in PR8- infected mice showed significant reductions systemically but not locally of the inflammatory molecules, IL-6, IFN-g, TNF-a, IL-12p70 and CCL2. In the post-acute phase of infection, PPS demonstrated a reduction in the pulmonary fibrotic biomarkers, sICAM-1 and complement factor C5b9.

Discussion

The systemic and local anti-inflammatory actions of PPS may regulate acute and post-acute pulmonary inflammation and tissue remodeling mediated by PR8 infection, which warrants further investigation.

Berberine regulates pulmonary inflammatory microenvironment and decreases collagen deposition in response to bleomycin-induced pulmonary fibrosis in mice

The purpose of this study was to explore the protective effect and potential mechanism of berberine on bleomycin (BLM)-induced fibrosis after lung injury in conjunction with network pharmacology. Berberine and pulmonary fibrosis prediction targets were collected for Gene Ontology (GO) functional analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis and so forth. A single intranasal dose of BLM (2.5 mg/kg) was administered to establish a model of fibrosis after lung injury, and berberine (50 mg/kg) was administered intraperitoneally daily for treatment. Network pharmacology results suggested that the mitogen-activated protein kinase (MAPK) signalling pathway may be a potential mechanism of berberine in delaying pulmonary fibrosis. The results of animal experiments showed that compared with the BLM group, after 14 days of berberine treatment, lung inflammatory cell aggregation was reduced and the expression levels of tumour necrosis factor-α (TNF-α), interleukin (IL)-8 and IL-6 were down-regulated in mice (p < 0.05); after 42 days of berberine treatment, the expression levels of transforming growth factor (TGF)-β1, platelet-derived growth factor-AB (PDGF-AB), hydroxyproline (HYP) and α-smooth muscle actin (α-SMA) were significantly down-regulated (p < 0.05), and the expression levels of total p38 MAPKα and p38 MAPKα (pT180/Y182) were down-regulated also (p < 0.05), inhibited collagen production and deposition, and increased the survival rate of mice to 70%. In conclusion, berberine attenuated inflammation mice, inhibited collagen production and showed some anti-pulmonary fibrosis potential in the MAPK signalling pathway.

A Novel Gene Signature Associated with Inflammatory Responses and Immune Status Assists in Prognosis and Intervention for Patients with HCC

BACKGROUND

Tumor growth depends on tumor cells and the tumor microenvironment, which are regulated by inflammation and immune responses. However, the roles of inflammation and immune status in hepatocellular carcinoma (HCC) remain unclear. The aim of this study was to evaluate the prognostic value of an inflammatory response- related gene signature associated with immune status, which may provide insight into new treatment options for HCC patients.

MATERIALS AND METHODS

Differentially expressed genes associated with inflammation were obtained from The Cancer Genome Atlas (TCGA), the Gene Expression Omnibus, and the Molecular Signatures Database. An inflammation-associated prognostic gene signature was constructed and validated using TCGA and the International Cancer Genome Consortium datasets, respectively, using LASSO Cox regression analysis. Log-rank was performed to compare the overall survival of low- and high-risk score cohorts. Immune cell infiltration and immune-related functions were analyzed using single-sample gene enrichment analysis. The structures of the drugs identified by the prognostic model were predicted using PubChem. The drugs sensitivity of bleomycin, simvastatin and zoledronate detected by CCK8 colorimetric assay. The mRNA levels of 7 genes in HCC after drug treatment analyzed via qRT-PCR.

RESULTS

Inflammation-associated genes, including ITGA5, MEP1A, P2RX4, RIPK2, SLC7A1 and SRI, were identified and found to be associated with the prognosis of HCC. We further found that the high-risk patients experienced poor prognosis, which was observed to be an independent and significant risk factor for prognosis. Moreover, we observed elevated expression levels in multiple immune cell types and immune function. Lastly, we validated that bleomycin, simvastatin and zoledronate could regulate these genes in HCC.

CONCLUSION

The inflammatory-response-associated gene signature could predict the prognosis and the immunological status of HCC patients. Additionally, bleomycin, simvastatin and zoledronate may represent potential drug candidates that could inhibit these genes. This may constitute a new approach for the treatment of HCC.

Bile pigments in emergency and critical care medicine

Bile pigments, such as bilirubin and biliverdin, are end products of the heme degradation pathway in mammals and are widely known for their cytotoxic effects. However, recent studies have revealed that they exert cytoprotective effects through antioxidative, anti-inflammatory, and immunosuppressive properties. All these mechanisms are indispensable in the treatment of diseases in the field of emergency and critical care medicine, such as coronary ischemia, stroke, encephalomyelitis, acute lung injury/acute respiratory distress syndrome, mesenteric ischemia, and sepsis. While further research is required before the safe application of bile pigments in the clinical setting, their underlying mechanisms shed light on their utilization as therapeutic agents in the field of emergency and critical care medicine. This article aims to summarize the current understanding of bile pigments and re-evaluate their therapeutic potential in the diseases listed above.

Focus on long non-coding RNA MALAT1: Insights into acute and chronic lung diseases

Acute lung injury (ALI) is a pulmonary illness with a high burden of morbidity and mortality around the world. Chronic lung diseases also represent life-threatening situations. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a type of long non-coding RNA (lncRNA) and is highly abundant in lung tissues. MALAT1 can function as a competitive endogenous RNA (ceRNA) to impair the microRNA (miRNA) inhibition on targeted messenger RNAs (mRNAs). In this review, we summarized that MALAT1 mainly participates in pulmonary cell biology and lung inflammation. Therefore, MALAT1 can positively or negatively regulate ALI and chronic lung diseases (e.g., chronic obstructive pulmonary disease (COPD), bronchopulmonary dysplasia (BPD), pulmonary fibrosis, asthma, and pulmonary hypertension (PH)). Besides, we also found a MALAT1-miRNA-mRNA ceRNA regulatory network in acute and chronic lung diseases. Through this review, we hope to cast light on the regulatory mechanisms of MALAT1 in ALI and chronic lung disease and provide a promising approach for lung disease treatment.

Lung fibrogenic microenvironment in mouse reconstitutes human alveolar structure and lung tumor

A mesenchymal cell activation is a hallmark event of pulmonary fibrosis. Alveolar type 2 (AT2) cells are progenitor cells that maintain alveolar homeostasis, and their damage is assumed to be an initiating event for pulmonary fibrosis. However, the interaction between the lung fibrogenic microenvironment and AT2 cell dynamics remains to be elucidated. Here, we report a unique role of the lung fibrogenic microenvironment, where cell type-specific tissue reconstruction is achieved by exogenous cell transplantation. We found that in the lung fibrogenic microenvironment the AT2 cell pool was depleted, whereas mesenchymal cells could promote intact AT2 cell proliferation in vitro. Furthermore, exogenously transplanted AT2 cells formed alveolar colonies and ameliorated pulmonary fibrosis. Exogenous tumor cells formed tumor nests with relevant histological and transcriptional properties. Human primary cells were adaptable to this microenvironment, facilitating epithelial cell-targeted therapy in pulmonary fibrosis and the establishment of patient-derived xenografts for precision medicine in lung cancer.

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Severe bleomycin-induced lung injury causes a significant AT2 cell loss

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Mesenchymal cells in the fibrogenic lung supports AT2 cell proliferation

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AT2 cell transplantation ameliorates bleomycin-induced pulmonary fibrosis

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Novel orthotopic lung cancer models are established for patient-derived xenografts

Pharmacokinetics of bleomycin sclerotherapy in patients with vascular malformations

Bleomycin, a chemotherapy agent that inhibits synthesis of DNA, has been increasingly utilized in sclerotherapy for patients with vascular malformations. A serious long-term risk of intravenous bleomycin is dose-dependent interstitial pneumonitis. Little is known about absorption and circulating levels of bleomycin when used in sclerotherapy for patients with vascular malformations. This is an Institutional Review Board (IRB)-approved prospective study on patients receiving bleomycin sclerotherapy in the management of vascular malformations. Depending on the type of vascular malformation, bleomycin was administered either in the lumen or interstitial space of the involved lesion. A bleomycin assay measured serum bleomycin plasma concentrations versus time at seven intervals following treatment. Pharmacokinetic parameters were obtained for each participant and included peak plasma concentration (C_max ), time to reach peak plasma concentration (T_max ), volume of distribution (V_d ), elimination half-life (t_1/2 ), the volume of plasma cleared of the drug per unit time (CL), and total systemic exposure area under the curve (AUC). Fifteen patients were enrolled (5: lymphatic, 4: venous, 6: arteriovenous malformations). Bleomycin was administered interstitially (IS) in 11 patients and intraluminal (IL) in four; median age of 13 years (range: 2-67). Pharmacokinetic analysis revealed terminal elimination half-life (t_1/2λz ) of 88.51 (±23.09) and 111.61 (±37.75) minutes for the IS and IL groups, respectively. V_d was 4.86 L (±6.74) and 1.55 L (±0.54) for the IS and IL groups, respectively. AUC was 53.9 (±23.45) and 129.17 (±93.57) mg min/L for the IS and IL groups, respectively. There were no statistically significant differences in t_1/2λz , V_d , or AUC parameters between groups. Bleomycin is absorbed systemically when used as a sclerosant for vascular malformations when injected either IS or IL.

Bleomycin-Induced Lung Injury After Intravenous Iron Administration

Bleomycin is an antibiotic that is often used as a chemotherapeutic agent due to its antitumor activities against a variety of malignancies. A feared and often fatal side effect of this drug is a pulmonary injury causing inflammation that can progress to pulmonary fibrosis. Bleomycin damages lung endothelial cells by the production of free radicals that can only occur when it is bound to certain metals in the body. It forms a complex with iron and once activated by iron reduction, it destroys deoxyribonucleic acid (DNA). Therefore, it is suggested that the availability of iron in the body may play a role in the pathogenesis of bleomycin toxicity although no related cases have been documented. This is a case of a 75-year-old female with no prior history of pulmonary disease who was diagnosed with Hodgkin’s lymphoma and received 12 doses of bleomycin over the course of six cycles of chemotherapy. She then presented to the hospital with respiratory failure five months after her completion of treatment. Interestingly, one month prior to presentation, she was given two intravenous iron infusions of ferumoxytol five days apart for the treatment of iron deficiency anemia. Within a week of receiving the iron, she developed dyspnea with a nonproductive cough. About a month after she developed these symptoms, she presented to the hospital and was found to be hypoxic with any activity and was subsequently placed on oxygen via nasal cannula. Her lung imaging showed new reticulonodular and patchy infiltrates bilaterally concerning for pneumonitis and her physical examination was significant for black discoloration of her fingertips and toes along with expiratory rhonchi heard throughout her lungs. During the hospitalization, her oxygen requirements increased, and the patient ended up in the intensive care unit on bilevel positive airway pressure. Her lung imaging, rapid progression, and skin findings made the clinical diagnosis of bleomycin toxicity. Out of concern that the intravenous iron may have played a role in the toxicity, iron chelation was attempted. The patient was given two doses of deferoxamine over two consecutive days and her symptoms of dyspnea along with her oxygen requirements improved. Unfortunately, these positive effects only lasted a few days and the patient continued to decline and ultimately passed away.

This case raises many questions regarding iron’s role in bleomycin toxicity, including if intravenous iron infusions may increase the risk of pulmonary injury from bleomycin. There are currently no guidelines or recommendations that suggest withholding iron supplementation in patients undergoing chemotherapy with bleomycin. There is also insufficient evidence to support the routine use of iron chelation in a patient that presents with bleomycin-induced lung injury. However, some studies suggest that iron chelation may play a role in preventing pulmonary toxicity. It may also lessen the severity of the toxicity or improve some of the related symptoms, thus warranting further research.

Role and Mechanism of Keap1/Nrf2 Signaling Pathway in the Regulation of Autophagy in Alleviating Pulmonary Fibrosis

A variety of internal and external lung diseases may eventually lead to pulmonary fibrosis, and insufficient autophagy is closely related to pulmonary fibrosis. This research is aimed to explore the mechanism of autophagy to alleviate pulmonary fibrosis. Then, a mouse model of pulmonary fibrosis induced by boromycin and histopathological lesions of the lungs of mice were observed by HE staining, which Masson staining assessed the degree of fibrosis in the lung tissue by detecting the expression of hydroxyproline in the tissue. RT-qPCR and western blotting were used to detect the levels of autophagy and Keap1/Nrf2 signaling pathway-related proteins. It was proved that autophagy-related proteins MAP1LC3(LC3) and Beclin 1 were decreased in mice with pulmonary fibrosis, while the expression of p62 was increased. Mice with pulmonary fibrosis worsened after injection of a 3-MA autophagy inhibitor, while injection of autophagy activation of rapamycin agent promoted Nrf2 nuclear mobilization. In a word, autophagy relieves pulmonary fibrosis through the activation of the Keap1/Nrf2 signaling pathway.

Target-induced activation of DNAzyme for highly sensitive colorimetric detection of bleomycin via DNA scission

In this work, a label-free and sensitive colorimetric sensing strategy for the detection of bleomycin (BLM) was developed on the basis of BLM-mediated activation of G-quadruplex DNAzyme via DNA strand scission. A G-quadruplex based hairpin probe (G4HP) containing the scission site (5'-GT-3') of BLM at the loop region and guanine (G)-rich sequences at its 5'-end was employed in this protocol. In the presence of BLM, it may cleave the 5'-GT-3' site of the hairpin probe with Fe(ii) as a cofactor, releasing the G-tetrads DNA fragment, which may further bind hemin to form a catalytic G-quadruplex-hemin DNAzyme. The resultant G-quadruplex DNAzyme has notable peroxidase-like activity, which effectively catalyzes the oxidation of 2,2'-azino-bis(3-ethylbenzothiozoline-6-sulfonic acid) (ABTS) by H₂O₂ to produce the blue-green-colored free-radical cation (ABTS^·+). Therefore, the detection of BLM can be achieved by observing the color transition with the naked eye or measuring the absorbance at a wavelength of 420 nm using a UV-Vis spectrophotometer. Attributing to the specific BLM-induced DNA strand scission and the effective locking of G-tetrads in the stem of the G4HP, the colorimetric sensing strategy exhibits high sensitivity and selectivity for detection of BLM in human serum samples, which might hold great promise for BLM assay in biomedical and clinical research.

Histopathological Impact of Bleomycin on Lung Injury and Development of Mediastinal Fat-Associated Lymphoid Clusters in the Lymphoproliferative Mouse Model

The purpose of this study is to elucidate the impact of bleomycin on the degree of lung injury and development of mediastinal fat-associated lymphoid clusters (MFALCs) in the lymphoproliferative mouse model (MRL/MpJ-Faslpr/lpr “Lpr”) and its control strain (MRL/MpJ “MpJ”). We analyzed immune cells, the degree of proliferation, lymphatic vessels (LVs), and high endothelial venules (HEVs) in lungs and MFALCs in Lpr and MpJ mice on the 7th and 21st days following intranasal instillation of either bleomycin (BLM group) or PBS (PBS group). The BLM group showed a significant increase in the size of MFALCs, lung injury score, and positive area ratios of LVs, HEVs, and immune cells (especially macrophages, B- and T-lymphocytes) on both days 7 and 21. Interestingly, the lungs in the BLM group on day 21 showed higher collagen deposition and cellular infiltration in MpJ and Lpr, respectively. Moreover, significant positive correlations were observed between the size of MFALCs and lung injury. In conclusion, BLM could exert lung fibrosis or lymphoproliferative infiltration in chronic stages in MpJ and Lpr, respectively, and this varied effect could be due to the variations in the degree of immune cell proliferation and the development of LVs and HEVs among the studied strains.

Construction of MicroRNA-mRNA Regulatory Network in the Molecular Mechanisms of Bleomycin-Induced Pulmonary Fibrosis

Bleomycin is a common antitumor agent used to treat many different types of malignancies; however, its main side effect is pulmonary fibrosis. The mechanism of bleomycin-induced pulmonary fibrosis (BIPF) has not been fully elucidated. Therefore, to further explore the molecular mechanisms of BIPF, we screened for microRNA (miRNA) and mRNA expression obtained from BIPF samples from the Gene Expression Omnibus database. Subsequently, we identified the differentially expressed miRNAs and genes that overlapped with the differentially expressed miRNAs target genes, predicted by using the miRWalk database selected as a candidate. The candidate genes were visualized based on Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes analyses. A protein-protein interaction network was constructed. Hub differentially expressed genes were selected and corresponding miRNAs to construct a miRNA-mRNA regulation network. Then, we chose three key miRNAs to study their regulatory relationship in bleomycin-induced pulmonary fibrosis. Finally, mouse lung epithelial cells TC-1 and MLE-12 were treated with bleomycin with qPCR to validate the results of three important hub genes and all key miRNAs. And dual-luciferase report experiment was carried out to verify the interaction of mmu-miR-1946a and serpina3n. The results revealed that the imbalance of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) plays a pivotal role in the occurrence and development of BIPF. In addition, Serpina3n and mmu-miR-1946a were proved interaction and may be involved in the regulation of the balance between MMP-9 and TIMP-1. The experimental results also verify the analysis. Our findings provide new insights into the key mediators and pathways related to the molecular mechanisms of BIPF.

Potential “Therapeutic” Effects of Tocotrienol-Rich Fraction (TRF) and Carotene “Against” Bleomycin-Induced Pulmonary Fibrosis in Rats via TGF-β/Smad, PI3K/Akt/mTOR and NF-κB Signaling Pathways

Background: Pulmonary fibrosis (PF) is a chronic, progressive, and, ultimately, terminal interstitial disease caused by a variety of factors, ranging from genetics, bacterial, and viral infections, to drugs and other influences. Varying degrees of PF and its rapid progress have been widely reported in post-COVID-19 patients and there is consequently an urgent need to develop an appropriate, cost-effective approach for the prevention and management of PF. Aim: The potential “therapeutic” effect of the tocotrienol-rich fraction (TRF) and carotene against bleomycin (BLM)-induced lung fibrosis was investigated in rats via the modulation of TGF-β/Smad, PI3K/Akt/mTOR, and NF-κB signaling pathways. Design/Methods: Lung fibrosis was induced in Sprague-Dawley rats by a single intratracheal BLM (5 mg/kg) injection. These rats were subsequently treated with TRF (50, 100, and 200 mg/kg body wt/day), carotene (10 mg/kg body wt/day), or a combination of TRF (200 mg/kg body wt/day) and carotene (10 mg/kg body wt/day) for 28 days by gavage administration. A group of normal rats was provided with saline as a substitute for BLM as the control. Lung function and biochemical, histopathological, and molecular alterations were studied in the lung tissues. Results: Both the TRF and carotene treatments were found to significantly restore the BLM-induced alterations in anti-inflammatory and antioxidant functions. The treatments appeared to show pneumoprotective effects through the upregulation of antioxidant status, downregulation of MMP-7 and inflammatory cytokine expressions, and reduction in collagen accumulation (hydroxyproline). We demonstrated that TRF and carotene ameliorate BLM-induced lung injuries through the inhibition of apoptosis, the induction of TGF-β1/Smad, PI3K/Akt/mTOR, and NF-κB signaling pathways. Furthermore, the increased expression levels were shown to be significantly and dose-dependently downregulated by TRF (50, 100, and 200 mg/kg body wt/day) treatment in high probability. The histopathological findings further confirmed that the TRF and carotene treatments had significantly attenuated the BLM-induced lung injury in rats. Conclusion: The results of this study clearly indicate the ability of TRF and carotene to restore the antioxidant system and to inhibit proinflammatory cytokines. These findings, thus, revealed the potential of TRF and carotene as preventive candidates for the treatment of PF in the future.

GSH-Responsive Drug Delivery System for Active Therapy and Reducing the Side Effects of Bleomycin

The application of drug delivery system (DDS) has achieved breakthroughs in many aspects, especially in the field of tumor treatment. In this work, polyethylene glycol (PEG)-modified hollow mesoporous manganese dioxide (HMnO₂@PEG) nanoparticles were used to load the anti-tumor drug bleomycin (BLM). When the DDS reached the tumor site, HMnO₂@PEG was degraded and reduced to Mn²⁺ by the overexpression of glutathione in the tumor microenvironment, and the drug was released simultaneously. BLM coordinated with Mn²⁺ in situ, thereby greatly improving the therapeutic activity of BLM. The results of in vivo and in vitro treatment experiments showed that the DDS had excellent responsive therapeutic activation ability. In addition, Mn²⁺ exhibited strong paramagnetism and was used for T₁-weighted magnetic resonance imaging in vivo. Furthermore, this therapeutic mode of responsively releasing drugs and activating in situ effectively attenuated pulmonary fibrosis initiated by BLM. In short, this DDS could help in avoiding the side effects of drugs.

Advances in heterocycles as DNA intercalating cancer drugs

The insertion of a molecule between the bases of DNA is known as intercalation. A molecule is able to interact with DNA in different ways. DNA intercalators are generally aromatic, planar, and polycyclic. In chemotherapeutic treatment, to suppress DNA replication in cancer cells, intercalators are used. In this article, we discuss the anticancer activity of 10 intensively studied DNA intercalators as drugs. The list includes proflavine, ethidium bromide, doxorubicin, dactinomycin, bleomycin, epirubicin, mitoxantrone, ellipticine, elinafide, and echinomycin. Considerable structural diversities are seen in these molecules. Besides, some examples of the metallo-intercalators are presented at the end of the chapter. These molecules have other crucial properties that are also useful in the treatment of cancers. The successes and limitations of these molecules are also presented.

Bimodal fibrosis in a novel mouse model of bleomycin-induced usual interstitial pneumonia

Idiopathic pulmonary fibrosis is pathologically represented by usual interstitial pneumonia (UIP). Conventional bleomycin models used to study pathogenic mechanisms of pulmonary fibrosis display transient inflammation and fibrosis, so their relevance to UIP is limited. We developed a novel chronic induced-UIP (iUIP) model, inducing fibrosis in D1CC×D1BC transgenic mice by intra-tracheal instillation of bleomycin mixed with microbubbles followed by sonoporation (BMS). A bimodal fibrotic lung disease was observed over 14 wk, with an acute phase similar to nonspecific interstitial pneumonia (NSIP), followed by partial remission and a chronic fibrotic phase with honeycombing similar to UIP. In this secondary phase, we observed poor vascularization despite elevated PDGFRβ expression. γ2PF- and MMP7-positive epithelial cells, consistent with an invasive phenotype, were predominantly adjacent to fibrotic areas. Most invasive cells were Scgb1a1 and/or Krt5 positive. This iUIP mouse model displays key features of idiopathic pulmonary fibrosis and has identified potential mechanisms contributing to the onset of NSIP and progression to UIP. The model will provide a useful tool for the assessment of therapeutic interventions to oppose acute and chronic fibrosis.

Comparison of 3D airway models for the assessment of fibrogenic chemicals

Lung epithelial cells and fibroblasts play key roles in pulmonary fibrosis and are involved in fibrotic signaling and production of the extracellular matrix (ECM), respectively. Recently, 3D airway models consisting of both cell types have been developed to evaluate the fibrotic responses while facilitating cell-cell crosstalk. This study aimed to evaluate the fibrotic responses in these models using different fibrogenic agents, which are known as key events in adverse outcome pathways of pulmonary fibrosis. We quantified cell injury and several sequential steps in fibrogenesis, including inflammation, the epithelial-mesenchymal transition (EMT), fibroblast activation, and ECM accumulation, using two different 3D airway models, the EpiAirway™-full thickness (Epi/FT) and MucilAir™-human fibroblast (Mucil/HF) models. In the Epi/FT model, fibrogenic agents induced the expression of inflammation and EMT-associated markers, while in the Mucil/HF model, they induced fibroblast activation and ECM accumulation. Using this information, we conducted gene ontology term network analysis. In the Epi/FT model, the terms associated with cell migration and response to stimulus made up a large part of the network. In the Mucil/HF model, the terms associated with ECM organization and cell differentiation and proliferation constituted a great part of the network. Collectively, our data suggest that polyhexamethyleneguanidine phosphate and bleomycin induce different responses in the two 3D airway models. While Epi/FT was associated with inflammatory/EMT-associated responses, Mucil/HF was associated with fibroblast-associated responses. This study will provide an important basis for selecting proper 3D airway models and fibrogenic agents to further research or screen chemicals causing inhalation toxicity.

Iron overload and mitochondrial dysfunction orchestrate pulmonary fibrosis

Pulmonary fibrosis (PF) is a chronic, progressive heterogeneous disease of lung tissues with poor lung function caused by scar tissue. Due to our limited understanding of its mechanism, there is currently no treatment strategy that can prevent the development of PF. In recent years, iron accumulation and mitochondrial damage have been reported to participate in PF, and drugs that reduce iron content and improve mitochondrial function have shown significant efficacy in animal experimental models. Excessive iron leads to mitochondrial impairment, which may be the key cause that results in the dysfunction of various kinds of pulmonary cells and further promotes PF. As an emerging research hotspot, there are few targeted effective therapeutic strategies at present due to limited mechanistic understanding. In this review, the roles of iron homeostasis imbalance and mitochondrial damage in PF are summarized and discussed, highlighting a promising direction for finding truly effective therapeutics for PF.

Deficiency of CARMA3 attenuates the development of bleomycin induced pulmonary fibrosis

BACKGROUND

Pulmonary fibrosis (PF) has attracted more and more attention due to its irreversibility and high mortality rate. Currently, there is no effective treatment option is available to reverse the disease. Caspase recruitment domain-containing membrane-associated guanylate kinase protein (CARMA3) has been recognized as a proinflammatory molecule involved in many lung diseases, such as Allergic airway inflammation and lung cancer. Bleomycin (Bleo), as an alkaline sugar peptide antibiotics, is often used as a first-line anti-tumor agent. Its toxic effect is to induce pulmonary fibrosis (PF) and its clinical symptoms, so it has been widely used in the construction of pulmonary fibrosis model.

METHODS

Wild type mice (WT, n = 20) and CARMA3 knockout mice (CARMA3-KO, n = 20) were generated and injected with bleomycin or saline via trachea. The severity of fibrosis was evaluated by fibrosis markers and lung histological morphology. Furthermore, the amount of alveolar epithelial cells and inflammation in lung tissue were examined. Finally, epithelial-mesenchymal transition was further investigated.

RESULTS

We found CARMA3 expression in the mice alveolar epithelial cells. And compared with WT mice, CARMA3-KO mice showed reduced deposition of collagen fibers, inflammation and destruction of alveolar epithelial cells in lung tissue. In addition, after bleomycin induction, the expressions of proinflammatory factors and collagen-related factors in CARMA3-KO mice were much lower than those in WT mice. The epithelial-mesenchymal transformation phenotype was also improved in CARMA3-KO mice compared to WT mice.

CONCLUSION

Our Results shows that CARMA3 plays an important role in the pathogenesis of bleomycin-induced pulmonary fibrosis. CARMA3 could alleviate the fibrosis by improving inflammation, deposition of collagen and damage of alveolar epithelial cells, which revealed that CARMA3 may be a potential target for pulmonary fibrosis.

Evaluating the protective role of Deglycyrrhizinated licorice root supplement on bleomycin induced pulmonary oxidative damage

The goal of this study was to investigate the protective effect of licorice supplements in a rat model of Bleomycin-induced lung oxidative damage over a duration of one month. The rats were randomly divided into six groups (n = 10 per group). Control group; Bleomycin group (B): rats were IP injected with bleomycin 5 mg/kg twice weekly. Licorice group (L): rats received orally 300 mg/kg licorice extract. Bleomycin and a low dose of Licorice group (BLLG): rats received orally 75 mg/kg licorice daily and injected as the B group. Bleomycin and a middle dose of Licorice group (BMLG): rats received orally 150 mg/kg licorice daily and injected as the Bleomycin group. Bleomycin and a high dose of Licorice group (BHLG): rats received orally 300 mg/kg licorice daily and injected as the Bleomycin group. Treatment with Bleomycin induced inflammation and oxidative damage to the lungs expressed in the disturbance of the measured parameters in the blood serum, the lung tissue, and the broncholavage fluid. In addition to the decreased expression of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and catalase (CAT) in the lung tissues. Bleomycin caused deformative changes in the histopathological and cellular examination of the lungs especially in the alveolar cells and the interstitial space. On the other hand, treated the bleomycin group with different doses of licorice supplement activates the antioxidant defense mechanism and attenuates the oxidative damage and damage induced to the lung. In conclusion, Deglycyrrhizinated licorice root supplement provided strong antioxidant and protective effects on Bleomycin-induced lung damage.

Sex-Related Differences in Murine Models of Chemically Induced Pulmonary Fibrosis

We developed two models of chemically induced chronic lung injury and pulmonary fibrosis in mice (intratracheally administered hydrochloric acid (HCl) and intratracheally administered nitrogen mustard (NM)) and investigated male–female differences. Female mice exhibited higher 30-day survival and less weight loss than male mice. Thirty days after the instillation of either HCl or NM, bronchoalveolar lavage fluid displayed a persistent, mild inflammatory response, but with higher white blood cell numbers and total protein content in males vs. females. Furthermore, females exhibited less collagen deposition, milder pulmonary fibrosis, and lower Ashcroft scores. After instillation of either HCl or NM, all animals displayed increased values of phosphorylated (activated) Heat Shock Protein 90, which plays a crucial role in the alveolar wound-healing processes; however, females presented lower activation of both transforming growth factor-β (TGF-β) signaling pathways: ERK and SMAD. We propose that female mice are protected from chronic complications of a single exposure to either HCl or NM through a lesser activation of TGF-β and downstream signaling. The understanding of the molecular mechanisms that confer a protective effect in females could help develop new, gender-specific therapeutics for IPF.

Clioquinol Attenuates Pulmonary Fibrosis through Inactivation of Fibroblasts via Iron Chelation

Strict control of iron homeostasis is critical for the maintenance of normal lung function. Iron accumulates in the lungs of patients with idiopathic pulmonary fibrosis (PF), but the characteristics of iron metabolism in the pathogenesis of PF and related targeting therapeutics are not well studied. In this study, we investigated the cellular and molecular characteristics of iron metabolism in fibrotic lungs and further explored the efficacy of clioquinol (CQ) for the treatment of PF as well as its functional mechanism. Iron aggregates accumulated in the lungs of patients with idiopathic PF, and FTL (ferritin light chain) transcripts were increased in their pulmonary fibroblasts. In the bleomycin (BLM)-induced PF (BLM-PF) mouse model, pulmonary iron accumulation is a very early and concomitant event of PF. Labile iron pool levels in both fibroblasts and macrophages from the BLM-PF model were elevated, and iron metabolism was dysregulated. CQ attenuated PF induced by BLM and FITC, and iron-saturated CQ did not alleviate BLM-PF. Furthermore, CQ inhibited the activation of fibroblasts, including proliferation, fibrotic differentiation, proinflammatory cytokine secretion, and migration. In conclusion, our study demonstrated that CQ, acting as an iron chelator, attenuates experimental PF through inactivation of fibroblasts, providing support for targeting iron metabolism as a basis for PF treatment.

Myeloid cell dynamics in bleomycin-induced pulmonary injury in mice; effects of anti-TNFα antibody

Bleomycin is a cancer therapeutic known to cause lung injury which progresses to fibrosis. Evidence suggests that macrophages contribute to this pathological response. Tumor necrosis factor (TNF)α is a macrophage-derived pro-inflammatory cytokine implicated in lung injury. Herein, we investigated the role of TNFα in macrophage responses to bleomycin. Treatment of mice with bleomycin (3 U/kg, i.t.) caused histopathological changes in the lung within 3 d which culminated in fibrosis at 21 d. This was accompanied by an early (3-7 d) influx of CD11b+ and iNOS+ macrophages into the lung, and Arg-1+ macrophages at 21 d. At this time, epithelial cell dysfunction, defined by increases in total phospholipids and SP-B was evident. Treatment of mice with anti-TNFα antibody (7.5 mg/kg, i.v.) beginning 15-30 min after bleomycin, and every 5 d thereafter reduced the number and size of fibrotic foci and restored epithelial cell function. Flow cytometric analysis of F4/80+ alveolar macrophages (AM) isolated by bronchoalveolar lavage and interstitial macrophages (IM) by tissue digestion identified resident (CD11b-CD11c+) and immature infiltrating (CD11b+CD11c-) AM, and mature (CD11b+CD11c+) and immature (CD11b+CD11c-) IM subsets in bleomycin treated mice. Greater numbers of mature (CD11c+) infiltrating (CD11b+) AM expressing the anti-inflammatory marker, mannose receptor (CD206) were observed at 21 d when compared to 7 d post bleomycin. Mature proinflammatory (Ly6C+) IM were greater at 7 d relative to 21 d. These cells transitioned into mature anti-inflammatory/pro-fibrotic (CD206+) IM between 7 and 21 d. Anti-TNFα antibody heightened the number of CD11b+ AM in the lung without altering their activation state. Conversely, it reduced the abundance of mature proinflammatory (Ly6C+) IM in the tissue at 7 d and immature pro-fibrotic IM at 21 d. Taken together, these data suggest that TNFα inhibition has beneficial effects in bleomycin induced injury, restoring epithelial function and reducing numbers of profibrotic IM and the extent of pulmonary fibrosis.

Concomitant inhibition of hedgehog signalling and activation of retinoid receptors abolishes bleomycin-induced lung fibrosis

Pulmonary fibrosis is a devastating disease with unknown treatment. All-trans retinoic acid (ATRA) attenuates bleomycin-induced lung fibrosis by different mechanistic pathways. However, the role of retinoid receptors in lung fibrosis is still unclear. Forskolin (FSK), a potent inhibitor for the revolutionary hedgehog (Hh) signalling pathway, has a promising antifibrotic effect on other organs such as the liver. This study investigates the interplay between the retinoid receptors modulation and the Hh signalling pathway in bleomycin (BLM)-induced pulmonary fibrosis. Rats were randomised and administrated a single dose of 7.5 mg/kg of BLM alone and with ATRA, FSK and both of them. The effects of FSK and ATRA on lung functions, oxidative stress markers (malondialdehyde [MDA], glutathione [GSH], superoxide dismutase [SOD] and catalase [CAT]), retinoid markers (retinoic acid receptors [RAR] and rexinoid X receptors [RXR]) and Hh signalling markers (patched homolog 1 [Ptch-1], Smoothened [Smo] and glioblastoma-2 [Gli-2]) were assessed. In single therapies, ATRA and FSK ameliorated BLM-induced lung fibrosis. On the contrary, a combination of both drugs synergistically reversed the effect of BLM-induced lung fibrosis, as indicated by the enhancement of lung functions and the decrease of the α-smooth muscle actin (α-SMA) expression and collagen deposition. Additionally, FSK and ATRA ameliorated oxidative stress and inflammation, reduced transforming growth factor β1 (TGF-β1) levels and reversed the effect of BLM on the mRNA expression of Ptch-1, Smo and Gli-2. FSK inhibited the Hh pathway and also activated protein kinase A (PKA) that is, in part, involved in phosphorylation of RAR/RXR heterodimer (a key step in retinoid receptor activation). The present results suggest that a combination of FSK and ATRA has a promising therapeutic value for lung fibrosis management.

Histological and Physiological Studies of the Effect of Bone Marrow-Derived Mesenchymal Stem Cells on Bleomycin Induced Lung Fibrosis in Adult Albino Rats

BACKGROUND

Lung fibrosis is considered as an end stage for many lung diseases including lung inflammatory disease, autoimmune diseases and malignancy. There are limited therapeutic options with bad prognostic outcome. The aim of this study was to explore the effect of mesenchymal stem cells (MSCs) derived from bone marrow on Bleomycin (BLM) induced lung fibrosis in albino rats.

METHODS

30 adult female albino rats were distributed randomly into 4 groups; negative control group, Bleomycin induced lung fibrosis group, lung fibrosis treated with bone marrow-MSCs (BM-MSCs) and lung fibrosis treated with cell free media. Lung fibrosis was induced with a single dose of intratracheal instillation of BLM. BM-MSCs or cell free media were injected intravenously 28 days after induction and rats were sacrificed after another 28 days for assessment. Minute respiratory volume (MRV), forced vital capacity (FVC) and forced expiratory volume 1 (FEV1) were recorded using spirometer (Power lab data acquisition system). Histological assessment was performed by light microscopic examination of H&E, and Masson's trichrome stained sections and was further supported by morphometric studies. In addition, electron microscopic examination to assess ultra-structural changes was done. Confocal Laser microscopy and PCR were used as tools to ensure MSCs homing in the lung.

RESULTS

Induction of lung fibrosis was confirmed by histological examination, which revealed disorganized lung architecture, thickened inter-alveolar septa due excessive collagen deposition together with inflammatory cellular infiltration. Moreover, pneumocytes depicted variable degenerative changes. Reduction in MRV, FVC and FEV1 were recorded. BM-MSCs treatment showed marked structural improvement with minimal cellular infiltration and collagen deposition and hence restored lung architecture, together with lung functions.

CONCLUSION

MSCs are promising potential therapy for lung fibrosis that could restore the normal structure and function of BLM induced lung fibrosis.

Protection against chemotherapy- and radiotherapy-induced side effects: A review based on the mechanisms and therapeutic opportunities of phytochemicals

BACKGROUND

Although great achievements have been made in the field of cancer therapy, chemotherapy and radiotherapy remain the mainstay cancer therapeutic modalities. However, they are associated with various side effects, including cardiocytotoxicity, nephrotoxicity, myelosuppression, neurotoxicity, hepatotoxicity, gastrointestinal toxicity, mucositis, and alopecia, which severely affect the quality of life of cancer patients. Plants harbor a great chemical diversity and flexible biological properties that are well-compatible with their use as adjuvant therapy in reducing the side effects of cancer therapy.

PURPOSE

This review aimed to comprehensively summarize the molecular mechanisms by which phytochemicals ameliorate the side effects of cancer therapies and their potential clinical applications.

METHODS

We obtained information from PubMed, Science Direct, Web of Science, and Google scholar, and introduced the molecular mechanisms by which chemotherapeutic drugs and irradiation induce toxic side effects. Accordingly, we summarized the underlying mechanisms of representative phytochemicals in reducing these side effects.

RESULTS

Representative phytochemicals exhibit a great potential in reducing the side effects of chemotherapy and radiotherapy due to their broad range of biological activities, including antioxidation, antimutagenesis, anti-inflammation, myeloprotection, and immunomodulation. However, since a majority of the phytochemicals have only been subjected to preclinical studies, clinical trials are imperative to comprehensively evaluate their therapeutic values.

CONCLUSION

This review highlights that phytochemicals have interesting properties in relieving the side effects of chemotherapy and radiotherapy. Future studies are required to explore the clinical benefits of these phytochemicals for exploitation in chemotherapy and radiotherapy.

Bleomycin-induced pneumonitis in a young Ghanaian male with Hodgkin's Lymphoma

We report a case of a young Ghanaian male who developed Bleomycin Induced Pneumonitis (BIP) after being treated for Hodgkin's Lymphoma. Pulmonary toxicity is the most feared complication of bleomycin therapy despite its effectiveness in achieving cure in patients with Hodgkin's lymphoma and germ cell tumors. BIP has a significant mortality rate if detected late and a high index of suspicion is required in all patients on bleomycin-based therapies with sudden onset of respiratory symptoms.

Chrysin mitigates bleomycin-induced pulmonary fibrosis in rats through regulating inflammation, oxidative stress, and hypoxia

Pulmonary fibrosis is a chronic condition characterized by fibroblast proliferation, and the infiltration of inflammatory cells that can initiate local tissue hypoxia. In this study the effect of chrysin (50 mg/kg/orally) in a model of bleomycin (BLM)-induced pulmonary fibrosis was studied. Chrysin managed to decrease mortality rate associated with BLM instillation and it managed to improve lung architecture and lung fibrosis by decreasing hydroxyproline content and transforming growth factor-β1 (TGF-β1) protein expression. Chrysin showed anti-inflammatory effect displayed by the decrease in inflammatory cells infiltrates, the decline in permeability of the alveolar/capillary barrier and the reduction in lactate dehydrogenase (LDH) activity. Chrysin demonstrated potent antioxidant effect by decreasing lipid peroxidation, increasing antioxidant defense mechanisms by increasing superoxide dismutase (SOD) activity and reduced glutathione (GSH) content. Additionally, the effect of chrysin on nitric oxide (NOx) content was assessed, where chrysin decreased NOx, increased the protein expression of endothelial nitric oxide synthase (eNOS), and decreased inducible nitric oxide synthase (iNOS) protein expression. Chrysin also succeeded in decreasing thioredoxin-interacting protein (TXNIP), the negative regulator of thioredoxin system, showing potent antioxidant effect. Finally, both tissue and bronchoalveolar lavage fluid contents of hypoxia inducible factor one alpha (HIF1α) were decreased by chrysin indicating that chrysin decreased local tissue hypoxia. In conclusion, this study exposed a possible proof that chrysin could mitigate pulmonary fibrosis induced by BLM through its anti-inflammatory, antioxidant, antifibrotic effects and its effect in alleviating hypoxia.