Association of serum levels of laminin, type IV collagen, procollagen III N-terminal peptide, and hyaluronic acid with the progression of interstitial lung disease

Hyaluronic Acid is Associated with Severity and Prognosis in Patients with Community-Acquired Pneumonia

Purpose

Hyaluronic acid (HA) is a novel inflammatory biomarker with a prognostic value for several infectious diseases. This study investigated the association of HA with severity and prognosis in hospitalized patients with community-acquired pneumonia (CAP).

Patients and Methods

We analyzed the differences of HA levels in different groups. Logistic regression analysis was performed to identify independent risk factors for severe CAP (SCAP). The predictive value of HA for SCAP was assessed using receiver operating characteristic (ROC) curves. Kaplan-Meier survival analysis was used to compare 30-day mortality between the high and low HA groups.

Results

Compared to healthy controls (49.2 ± 15.3 ng/mL), patients with CAP exhibited significantly elevated levels of HA (P < 0.001). In CAP patients, increased HA levels were more pronounced in those with SCAP (SCAP vs non-SCAP:135.6 ± 51 ng/mL vs 100.7 ± 47.8 ng/mL, P < 0.001). Compared to survivors (109.9 ± 48.7 ng/mL), HA levels in non-survivors were significantly higher (180.9 ± 67.8 ng/mL) (P < 0.001). HA was an independent predictor of SCAP [odds ratio (OR): 1.013, 95% confidence interval (CI): 1.003-1.022, P = 0.011] with high diagnostic accuracy [areas under the curve (AUC): 0.709, 95% CI: 0.622-0.797, P = 0.001]. Additionally, HA was independently associated with death risk in patients with CAP (OR: 1.022, 95% CI: 1.005-1.039, P = 0.010). Kaplan-Meier survival curves indicated that CAP patients in the high HA group exhibit a higher 30-day mortality rate compared to those in the low HA group (8.6% vs 1.5%, P = 0.008). Post hoc analysis indicated that our study possessed 98.857% statistical power.

Conclusion

In conclusion, High HA levels are associated with severity and mortality in patients with CAP, and HA could serve as a novel serum biomarker to predict the risk of CAP progression.

It takes two peroxisome proliferator-activated receptors (PPAR-β/δ and PPAR-γ) to tango idiopathic pulmonary fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is characterized by aberrant lung epithelial phenotypes, fibroblast activation, and increased extracellular matrix deposition. Transforming growth factor-beta (TGF-β)1-induced Smad signaling and downregulation of peroxisomal genes are involved in the pathogenesis and can be inhibited by peroxisome proliferator-activated receptor (PPAR)-α activation. However, the three PPARs, that is PPAR-α, PPAR-β/δ, and PPAR-γ, are known to interact in a complex crosstalk.

METHODS

To mimic the pathogenesis of lung fibrosis, primary lung fibroblasts from control and IPF patients with comparable levels of all three PPARs were treated with TGF-β1 for 24 h, followed by the addition of PPAR ligands either alone or in combination for another 24 h. Fibrosis markers (intra- and extracellular collagen levels, expression and activity of matrix metalloproteinases) and peroxisomal biogenesis and metabolism (gene expression of peroxisomal biogenesis and matrix proteins, protein levels of PEX13 and catalase, targeted and untargeted lipidomic profiles) were analyzed after TGF-β1 treatment and the effects of the PPAR ligands were investigated.

RESULTS

TGF-β1 induced the expected phenotype; e.g. it increased the intra- and extracellular collagen levels and decreased peroxisomal biogenesis and metabolism. Agonists of different PPARs reversed TGF-β1-induced fibrosis even when given 24 h after TGF-β1. The effects included the reversals of (1) the increase in collagen production by repressing COL1A2 promoter activity (through PPAR-β/δ activation); (2) the reduced activity of matrix metalloproteinases (through PPAR-β/δ activation); (3) the decrease in peroxisomal biogenesis and lipid metabolism (through PPAR-γ activation); and (4) the decrease in catalase protein levels in control (through PPAR-γ activation) and IPF (through a combined activation of PPAR-β/δ and PPAR-γ) fibroblasts. Further experiments to explore the role of catalase showed that an overexpression of catalase protein reduced collagen production. Additionally, the beneficial effect of PPAR-γ but not of PPAR-β/δ activation on collagen synthesis depended on catalase activity and was thus redox-sensitive.

CONCLUSION

Our data provide evidence that IPF patients may benefit from a combined activation of PPAR-β/δ and PPAR-γ.

Ex vivo tissue perturbations coupled to single-cell RNA-seq reveal multilineage cell circuit dynamics in human lung fibrogenesis

Pulmonary fibrosis develops as a consequence of failed regeneration after injury. Analyzing mechanisms of regeneration and fibrogenesis directly in human tissue has been hampered by the lack of organotypic models and analytical techniques. In this work, we coupled ex vivo cytokine and drug perturbations of human precision-cut lung slices (hPCLS) with single-cell RNA sequencing and induced a multilineage circuit of fibrogenic cell states in hPCLS. We showed that these cell states were highly similar to the in vivo cell circuit in a multicohort lung cell atlas from patients with pulmonary fibrosis. Using micro-CT-staged patient tissues, we characterized the appearance and interaction of myofibroblasts, an ectopic endothelial cell state, and basaloid epithelial cells in the thickened alveolar septum of early-stage lung fibrosis. Induction of these states in the hPCLS model provided evidence that the basaloid cell state was derived from alveolar type 2 cells, whereas the ectopic endothelial cell state emerged from capillary cell plasticity. Cell-cell communication routes in patients were largely conserved in hPCLS, and antifibrotic drug treatments showed highly cell type-specific effects. Our work provides an experimental framework for perturbational single-cell genomics directly in human lung tissue that enables analysis of tissue homeostasis, regeneration, and pathology. We further demonstrate that hPCLS offer an avenue for scalable, high-resolution drug testing to accelerate antifibrotic drug development and translation.

Constructing an extracellular matrix-related prognostic model for idiopathic pulmonary fibrosis based on machine learning

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial lung disease. Multiple research has revealed that the extracellular matrix (ECM) may be associated with the development and prognosis of IPF, however, the underlying mechanisms remain incompletely understood.

METHODS

We included GSE70866 dataset from the GEO database and established an ECM-related prognostic model utilizing LASSO, Random forest and Support vector machines algorithms. To compare immune cell infiltration levels between the high and low risk groups, we employed the ssGSEA algorithm. Enrichment analysis was conducted to explore pathway differences between the high-risk and low-risk groups. Finally, the model genes were validated using an external validation set consisting of IPF cases, as well as single-cell data analysis.

RESULTS

Based on machine learning algorithms, we constructed an ECM-related risk model. IPF patients in the high-risk group had a worse overall survival rate than those in the low-risk group. The model's AUC predictive values were 0.786, 0.767, and 0.768 for the 1-, 2-, and 3-year survival rates, respectively. The validation cohort validated these findings, demonstrating our model's effective prognostication. Chemokine-related pathways were enriched through enrichment analysis. Moreover, immune cell infiltration varied significantly between the two groups. Finally, the validation results indicate that the expression levels of all the model genes exhibited significant differential expression.

CONCLUSIONS

Based on CST6, PPBP, CSPG4, SEMA3B, LAMB2, SERPINB4 and CTF1, our study developed and validated an ECM-related risk model that accurately predicts the outcome of IPF patients.

Serum hyaluronic acid and procollagen III, N-terminal propeptide levels are highly associated with disease severity and predict the progression of COVID-19

Background

The coronavirus disease 2019 (COVID-19) pandemic is a rapidly evolving global emergency and continuously poses a serious threat to public health, highlighting the urgent need of identifying biomarkers for disease severity and progression. In order to early identify severe and critical patients, we retrospectively analyze the clinical characteristics and risk indicators of severe disease in patients with corona virus disease 2019 (COVID-19).

Methods

A total of 420 confirmed COVID-19 patients were included in the study. According to the "Diagnosis and Treatment of novel coronavirus Pneumonia (10th Edition)", the cases were divided into mild group (n = 243) and severe group (n =177). Laboratory parameters were analyzed in combination with clinical data.

Results

Male patients over 46 years who have smoking habits were more likely to suffer from severe COVID-19. Critically ill patients had lower lymphocyte counts and red blood cell counts, and higher white blood cell counts (P<0.05). Expectedly, serum inflammatory factors (NLR, PLR, LMR, CLR, PCT, CRP), coagulation markers (APTT, PT, TT, FIB, D-Dimer), Myocardial damage markers (hs-TNT, LDH) were significantly increased (P<0.05) in severe COVID-19 patients. Surprisedly, those patients showed obviously elevated levels of common tumor markers (ProGRP, CYFRA21-1, SCC, NSE) (P<0.05). In this case, the levels of tumor marker reflected more the condition of inflammation than the growth of tumor. More importantly, HA and PIIIN-P were highly associated with COVID-19 severity. The AUC of the ROC curve for the diagnosis of severe COVID-19 by HA and PIIIN-P was 0.826. Meanwhile, HA was positively correlated with myocardial damage markers (hs-TNT, LDH). PIIIN-P was positively correlated with myocardial damage markers (hs-TNT, LDH) and inflammatory factors (NLR, PLR, LMR, CLR, ProGRP, SCC, PCT, CRP). On the contrary, PIIIN-P was negatively correlated with pulmonary function indexes (oxygenation index and oxygen saturation of hemoglobin).

Conclusion

HA and PIIIN-P are highly associated with disease severity and progression of COVID-19 and can be used as new markers for the prediction of severe COVID-19.

Potential biomarkers for diagnosis and disease evaluation of idiopathic pulmonary fibrosis

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease characterized by progressive lung fibrogenesis and histological features of usual interstitial pneumonia. IPF has a poor prognosis and presents a spectrum of disease courses ranging from slow evolving disease to rapid deterioration; thus, a differential diagnosis remains challenging. Several biomarkers have been identified to achieve a differential diagnosis; however, comprehensive reviews are lacking. This review summarizes over 100 biomarkers which can be divided into six categories according to their functions: differentially expressed biomarkers in the IPF compared to healthy controls; biomarkers distinguishing IPF from other types of interstitial lung disease; biomarkers differentiating acute exacerbation of IPF from stable disease; biomarkers predicting disease progression; biomarkers related to disease severity; and biomarkers related to treatment. Specimen used for the diagnosis of IPF included serum, bronchoalveolar lavage fluid, lung tissue, and sputum. IPF-specific biomarkers are of great clinical value for the differential diagnosis of IPF. Currently, the physiological measurements used to evaluate the occurrence of acute exacerbation, disease progression, and disease severity have limitations. Combining physiological measurements with biomarkers may increase the accuracy and sensitivity of diagnosis and disease evaluation of IPF. Most biomarkers described in this review are not routinely used in clinical practice. Future large-scale multicenter studies are required to design and validate suitable biomarker panels that have diagnostic utility for IPF.

Predictive Value of Collagen Biomarkers in Advanced Chronic Kidney Disease Patients

Patients with chronic kidney disease have an increased risk of all-cause death. The value of collagen biomarkers such as procollagen type I carboxy-terminal propeptide (PICP) and procollagen type III N-terminal peptide (P3NP), in end-stage renal disease (ESRD), has not yet been defined (in the literature and in clinics). The purpose of this study was to determine the potential value of these new biomarkers in the prediction of mortality in this population. Plasma PICP and P3NP levels were determined in 140 patients with ESRD, not yet on dialysis, who were followed up for 36 ± 5.3 months. During follow-up, 58 deaths were recorded (41.4%), with the majority of them being cardiovascular deaths (43, 74.13%). Using the ROC curve, the cut-off value for the prediction of mortality for PICP was 297.31 µg/L, while for P3NP, the cut-off value was 126.67 µg/L. In univariate analysis, a value of PICP above the cut-off point was associated with a fivefold increased risk of mortality (hazard ratio (HR) 5.071, 95% confidence interval 1.935-13.29, p = 0.001) and a value of P3NP above the cut-off point was associated with a twofold increased risk of mortality (HR 2.089, 95% CI 1.044-4.178, p = 0.002). In a multivariable Cox proportional hazards model, PICP values remained independent predictors of mortality (HR 1.22, 95% CI 1.1-1.31, p < 0.0001). Our data suggest that the collagen biomarker PICP is an independent predictor of mortality in ESRD patients who are not yet on dialysis.

Clinical Significance of Serum Collagen Type IV and Procollagen Type III N-Peptide Levels in Diagnosis and Differential Diagnosis of Lymphedema

Background: Lymphatic endothelial cells production or modification were closely related to the extracellular matrix (ECM) molecules. The serum hyaluronic acid (HA), laminin (LN), procollagen type III N-peptide (PIIINP), and collagen type IV (CGIV) levels were researched to explore the clinical significance of serum ECM proteins in the diagnosis and differentiation of lymphedema. Methods: Fifty-five patients were enrolled. They were divided into primary lymphedema (PLE), secondary lymphedema (SLE), and venous edema (VE) groups. Twenty-two healthy controls were also recruited as normal control (NC). Serum HA, LN, PIIINP, and CGIV levels of all subjects were assessed using chemiluminescence immunoassay. Statistical analysis and receiver operating characteristic (ROC) curves were used to data analysis. Results: The serum levels of CGIV were significantly decreased in both PLE and SLE groups compared with those in the NC group. Reduced serum CGIV levels were associated with the severity of lymphedema. The serum levels of CGIV and PIIINP were identified decreased in both PLE and SLE groups compared with those in the VE group. However, the levels of serum HA and LN were not observed significantly changed in both PLE and SLE groups than those in NC or VE group. Furthermore, ROC curve indicated that serum CGIV and PIIINP were capable of providing good diagnostic and differential diagnostic efficacy at the most appropriate cutoff point value. Conclusion: The serum levels of CGIV may have clinical significance in the diagnosis of lymphedema. CGIV and PIIINP may play a role in the differentiation of lymphedema from VE.

Cell-Specific Response of NSIP- and IPF-Derived Fibroblasts to the Modification of the Elasticity, Biological Properties, and 3D Architecture of the Substrate

The fibrotic fibroblasts derived from idiopathic pulmonary fibrosis (IPF) and nonspecific interstitial pneumonia (NSIP) are surrounded by specific environments, characterized by increased stiffness, aberrant extracellular matrix (ECM) composition, and altered lung architecture. The presented research was aimed at investigating the effect of biological, physical, and topographical modification of the substrate on the properties of IPF- and NSIP-derived fibroblasts, and searching for the parameters enabling their identification. Soft and stiff polydimethylsiloxane (PDMS) was chosen for the basic substrates, the properties of which were subsequently tuned. To obtain the biological modification of the substrates, they were covered with ECM proteins, laminin, fibronectin, and collagen. The substrates that mimicked the 3D structure of the lungs were prepared using two approaches, resulting in porous structures that resemble natural lung architecture and honeycomb patterns, typical of IPF tissue. The growth of cells on soft and stiff PDMS covered with proteins, traced using fluorescence microscopy, confirmed an altered behavior of healthy and IPF- and NSIP-derived fibroblasts in response to the modified substrate properties, enabling their identification. In turn, differences in the mechanical properties of healthy and fibrotic fibroblasts, determined using atomic force microscopy working in force spectroscopy mode, as well as their growth on 3D-patterned substrates were not sufficient to discriminate between cell lines.

Dynamics of type IV collagen 7S fragment on eradication of HCV with direct antiviral agents: Prognostic and metabolomic impacts

BACKGROUND

Liver fibrosis is one of the cardinal clinical features of chronic hepatitis C (CHC). However, the mechanisms underlying the evolution and reversion of liver fibrosis after hepatitis C virus (HCV) eradication and their relationship with clinical outcomes and metabolic alterations are not fully elucidated. Whether any non-invasive fibrosis marker can predict prognosis is unknown.

METHODS

Between October 2014 and September 2019, 418 patients with CHC or compensated cirrhosis with HCV were prospectively recruited in this observational study. 326 patients that were successfully eradicated with interferon-free direct antiviral agents (IFN-free DAAs) were analyzed. Peri-treatment dynamics of serum levels of type IV collagen 7S fragment (4COL7S), a fibrosis marker, and subsequent clinical outcomes, including hepatic decompensation, newly emerged hepatocellular carcinoma (HCC), and all-cause mortality were analyzed.

RESULTS

Ten (3.1%) patients died during the observation period. 4COL7S-defined fibrosis progression (n = 97, 29.8%) at SVR was significantly correlated with worse all-cause mortality post-SVR (P = 0.0062) but not with the probability of newly emerged HCC (P = 0.24). Prognostic tendency was more prominent in patients with advanced fibrosis (P< 0.0001). 4COL7S-defined fibrosis progression at SVR and a baseline platelet count less than 10×104/μL were significantly predicted all-cause mortality (P = 0.0051). In exploratory analyses, a decreased 4COL7S at the end of treatment was correlated with a matrix-degrading phenotype that showed higher serum metalloproteinase to tissue inhibitors of metalloproteinase-1 ratios and characteristic metabolic fingerprints such as increased butyrate, some medium-chain fatty acids, anabolic amino acids, and decreased uremia toxins.

CONCLUSIONS

Peri-treatment dynamics of serum 4COL7S, a non-invasive fibrosis marker, predict prognosis. Non-invasive fibrosis markers may be useful biomarkers for risk stratification post-SVR.

Chimeric galectin-3 and collagens: Biomarkers and potential therapeutic targets in fibroproliferative diseases

Fibrosis, stiffening and scarring of an organ/tissue due to genetic abnormalities, environmental factors, infection, and/or injury, is responsible for > 40% of all deaths in the industrialized world, and to date, there is no cure for it despite extensive research and numerous clinical trials. Several biomarkers have been identified, but no effective therapeutic targets are available. Human galectin-3 is a chimeric gene product formed by the fusion of the internal domain of the collagen alpha gene [N-terminal domain (ND)] at the 5'-end of galectin-1 [C-terminal domain (CRD)] that appeared during evolution together with vertebrates. Due to the overlapping structural similarities between collagen and galectin-3 and their shared susceptibility to cleavage by matrix metalloproteases to generate circulating collagen-like peptides, this review will discuss present knowledge on the role of collagen and galectin-3 as biomarkers of fibrosis. We will also highlight the need for transformative approaches targeting both the ND and CRD domains of galectin-3, since glycoconjugate binding by the CRD is triggered by ND-mediated oligomerization and the therapies targeted only at the CRD have so far achieved limited success.

Effect of Roxadustat on Factors Associated with Renal Fibrosis and Efficacy

Objective

We investigated the effect of roxadustat on factors associated with renal fibrosis and efficacy. Methods. Sixty patients meeting the inclusion criteria between January 2021 and October 2021 were equally distributed into observation (roxadustat) group and control (Erythropoietin) group. Then, the expression of serum hypoxia-inducible factor 1-alpha (HIF-1α), transforming growth factor-β (TGF-β1), vascular endothelial growth factor (VEGF), fibronectin (FN), and collagen Ⅳ (C-IV) was compared at different time points (baseline, 2-week follow-up, and 4-week follow-up). The improvement degree of hemoglobin (Hb) and the change level of iron parameters and hepcidin were also compared between the two groups. Results. In the roxadustat group, the expression of HIF-1α at 2 weeks was significantly higher than the baseline and approached the baseline value at 4 weeks. At 4 weeks, TGF-β1 and FN expression was significantly lower than baseline. In addition, the improvement of Hb in the roxadustat group was significantly higher than that in the control group at 4 weeks, and the change of ferritin, transferrin, and hepcidin indexes from baseline was better than in the control group.

Conclusion

After giving roxadustat, it can change the expression of HIF-1α, TGF-β1, and FN. Its efficacy is superior to EPO, which is worthy of clinical application.

Pneumocystis jirovecii-associated immune reconstitution inflammatory syndrome-like phenomenon in a child with leukaemia: a case report and literature review

BACKGROUND

Immune reconstitution inflammatory syndrome (IRIS) refers to the phenomenon of intense immune responses against pathogens in patients with AIDS undergoing antiretroviral therapy to reconstitute immune function, resulting in functional impairment of multiple organs. Non-AIDS immunosuppressed hosts may also develop similar manifestations to IRIS during immune recovery.

CASE PRESENTATION

An 8-year-old girl presented with acute lymphoblastic leukaemia was admitted for scheduled chemotherapy treatment. During chemotherapy, she experienced pancytopenia and Pneumocystis jirovecii pneumonia, which was diagnosed based on the abnormal shadows observed on chest computed tomography, the elevation of serum β-D-glucan, and the positive mNGS results of Pneumocystis jirovecii in both sputum and blood. After treatment with Granulocyte Colony-Stimulating Factor, sulfamethoxazole, and caspofungin, aggravation of lung lesions was discovered and severe interstitial lung disease developed in a short period along with a rapidly increasing leukocyte count. Intravenous methylprednisolone pulse therapy was given, but lung function did not improve, and she finally died after the withdrawal of medical care.

CONCLUSIONS

For patients with acute lymphocytic leukaemia infected with Pneumocystis jirovecii, the rapid aggravation of pulmonary lesions in the process of blood recovery and immune reconstitution should raise vigilance against the possibility of IRIS-like reactions. The use of granulocyte stimulating factors may aggravate the inflammatory response in the lungs. The timing, dosage, and duration of treatment of glucocorticoids and the impact of high-dose methylprednisolone pulse therapy on the prognosis of patients should be explored in further research.

CA 15-3 prognostic biomarker in SARS-CoV-2 pneumonia

The severity of lung involvement is the main prognostic factor in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Carbohydrate antigen 15-3 (CA 15-3), a marker of lung damage and fibrosis, could help predict the prognosis of SARS-CoV-2 pneumonia. This was a retrospective and observational study. CA 15-3 was analyzed in the blood samples of patients consecutively admitted for SARS-CoV-2 pneumonia and whose blood samples were available in the biobank. Other prognostic markers were also measured (interleukin 6 [IL6], C-reactive protein [CRP], D-dimer, troponin T, and NT-ProBNP). The occurrence of in-hospital complications was registered, including death, the need for medical intensive care, and oxygen therapy at discharge. In this study, 539 patients were recruited (54.9% men, mean age: 59.6 ± 16.4 years). At admission, the mean concentrations of CA 15-3 was 20.5 ± 15.8 U/mL, and the concentration was correlated with male sex, older age, and other severity markers of coronavirus disease of 2019 (COVID-19) (IL6, CRP, D-dimer, troponine T, and NT-ProBNP). CA 15-3 levels were higher in patients who died (n = 56, 10.4%) (35.33 ± 30.45 vs. 18.8 ± 12.11, p < 0.001), who required intensive medical support (n = 78, 14.4%; 31.17 ± 27.83 vs. 18.68 ± 11.83; p < 0.001), and who were discharged with supplemental oxygen (n = 64, 13.3%; 22.65 ± 14.41 vs. 18.2 ± 11.7; p = 0.011). Elevated CA 15-3 levels (above 34.5 U/mL) were a strong predictor of a complicated in-hospital course, in terms of a higher risk of death (adjusted odds ratio [OR] 3.74, 95% confidence interval [CI]: 1.22–11.9, p = 0.022) and need for intensive care (adjusted OR 4.56, 95% CI: 1.37–15.8) after adjusting for all other risk factors. The degree of lung damage and fibrosis evaluated in terms of CA 15-3 concentrations may allow early identification of the increased risk of complications in patients with SARS-CoV-2 pneumonia.

Laryngopharyngeal pH Monitoring in Patients With Idiopathic Pulmonary Fibrosis

Background: Patients with idiopathic pulmonary fibrosis (IPF) often have irritating persistent dry cough. Possible correlations between dry cough and laryngopharyngeal reflux (LPR) remain unclear.

Methods: 44 patients with IPF and 30 healthy individuals underwent 24 h laryngopharyngeal pH monitoring. Ryan index score was calculated. Patients’ demographic and clinical data were collected.

Results: 44 patients with IPF and 30 healthy individuals were included. The proportions of men and smokers were significantly higher in IPF group than control group (All p < 0.01). The average laryngopharyngeal pH value for 24 h was similar in the IPF (7.11 ± 0.08) group and control group (7.09 ± 0.06). According to the percentage duration of pH < 6.5, pH6.5–7.5, and pH > 7.5 in the overall measure duration, the patients were classified into three pH groups. In entire pH monitoring duration, the proportion of pH > 7.5 group in IPF patients was higher than control group; at upright position, the proportion of pH > 7.5 group in IPF patients was higher than control group; at supine position, the proportion of pH < 6.5 group in IPF patients was higher than control group (All p < 0.01). Seven patients had Ryan index score>9.41 at upright position. All patients had Ryan index score<6.79 at supine position. Four patients showed significantly higher and one patient had significantly lower average pH at coughing than the overall average pH (All p < 0.05).

Conclusions: Patients with IPF may have LPR. Basic and acidic LPR may likely occur at upright and supine position, respectively. Ryan index may not accurately reflect LPR in patients with IPF.

Safety of inhaled ivermectin as a repurposed direct drug for treatment of COVID-19: A preclinical tolerance study

Introduction

SARS-CoV-2 replication in cell cultures has been shown to be inhibited by ivermectin. However, ivermectin's low aqueous solubility and bioavailability hinders its application in COVID-19 treatment. Also, it has been suggested that best outcomes for this medication can be achieved via direct administration to the lung.

Objectives

This study aimed at evaluating the safety of a novel ivermectin inhalable formulation in rats as a pre-clinical step.

Methods

Hydroxy propyl-β-cyclodextrin (HP-β-CD) was used to formulate readily soluble ivermectin lyophilized powder. Adult male rats were used to test lung toxicity for ivermectin-HP-β-CD formulations in doses of 0.05, 0.1, 0.2, 0.4 and 0.8 mg/kg for 3 successive days.

Results

The X-ray diffraction for lyophilized ivermectin-HP-β-CD revealed its amorphous structure that increased drug aqueous solubility 127-fold and was rapidly dissolved within 5 s in saline. Pulmonary administration of ivermectin-HP-β-CD in doses of 0.2, 0.4 and 0.8 mg/kg showed dose-dependent increase in levels of TNF-α, IL-6, IL-13 and ICAM-1 as well as gene expression of MCP-1, protein expression of PIII-NP and serum levels of SP-D paralleled by reduction in IL-10. Moreover, lungs treated with ivermectin (0.2 mg/kg) revealed mild histopathological alterations, while severe pulmonary damage was seen in rats treated with ivermectin at doses of 0.4 and 0.8 mg/kg. However, ivermectin-HP-β-CD formulation administered in doses of 0.05 and 0.1 mg/kg revealed safety profiles.

Conclusion

The safety of inhaled ivermectin-HP-β-CD formulation is dose-dependent. Nevertheless, use of low doses (0.05 and 0.1 mg/kg) could be considered as a possible therapeutic regimen in COVID-19 cases.

Circulating Procollagen Type III N-Terminal Peptide and Physical Function in Adults from the Long Life Family Study

BACKGROUND

Circulating levels of procollagen type III N-terminal peptide (P3NP) may reflect increased fibrosis of skeletal muscle and other tissues with aging. Herein, we tested if P3NP was associated with baseline and 7-year change in physical function.

METHOD

Participants (n = 400) were from the Long Life Family Study, a study of exceptional familial longevity. Plasma P3NP concentration was measured using a sandwich enzyme-linked immunosorbent assay (inter-assay coefficient of variation <5.5%). At baseline and 7-year follow-up visits, physical function was measured using the Short Physical Performance Battery (SPPB score 0-12), which consists of gait speed, balance, and chair-rise tests. Grip strength was measured using a handheld dynamometer. The association between log-transformed P3NP and physical function was examined using generalized estimating equations adjusted for familial relatedness, age, sex, height, weight, lifestyle characteristics, liver function, kidney function, lung function, and chronic disease prevalence.

RESULTS

Participants were aged 73.1 ± 15.2 years (range: 39-104), 54% female, had body mass index of 26.6 ± 4.3 kg/m2, and gait speeds of 1.0 ± 0.3 m/s. One standard deviation higher log-transformed P3NP was related to worse baseline SPPB score (β = -0.9points), gait speed (β = -0.05m/s), chair-rises per-second (β = -0.46chair-rises/10 seconds), and grip strength (β = -2.0kg; all p < .001). Higher P3NP was also associated with greater declines in gait speed (β = -1.41, p < .001) and transitioning to being unable to perform chair-rises (β = 0.41, p < .001) after 7 years.

CONCLUSION

Plasma P3NP may be a strong, novel biomarker of current and future physical function. Future research is needed to extend our findings to other cohorts and determine mechanisms underlying these associations.

Correlation of Krebs von den Lungen-6 and fibronectin with pulmonary fibrosis in coronavirus disease 2019

OBJECTIVE

Coronavirus Disease 2019 (COVID-19) caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still spreading worldwide, which may progress to pulmonary fibrosis (PF), leading to the worsen outcome. As the markers of lung injury, the correlation of Krebs von den Lungen-6 (KL-6) and fibronectin (Fn) with pulmonary fibrosis in COVID-19 was still unclear.

METHODS

113 patients diagnosed as COVID-19 were enrolled in this retrospective study, and divided into three categories as mild, moderate and severe cases. The concentrations of serum KL-6 and Fn at hospital admission were tested using the method of latex agglutination assay and immunoturbidimetic assay, respectively.

RESULTS

Compared with that in the non-severe COVID-19 cases and normal control subjects, serum KL-6 concentration on admission was significantly higher in the severe group, which was positively correlated with C-reactive protein, and negatively correlated with lymphocytes count. Whereas, no obvious elevation in serum Fn concentration was investigated in COVID-19 patients with the different phenotypes. The severe cases displayed the higher incident rate of pulmonary fibrosis at hospital discharge. Compared with non-PF patients, the COVID-19 cases with PF had the higher serum KL-6 values.

CONCLUSION

Serum KL-6 concentration was significantly elevated in severe COVID-19 patients, which may be useful for evaluating the disease severity. For early prevention of the development of pulmonary fibrosis, high concentrations of serum KL-6 in the early stage of COVID-19 should be paid close attention.

A systematic review of the incidence, risk factors and prognosis of acute exacerbation of systemic autoimmune disease-associated interstitial lung disease

Introduction

Acute exacerbation (AE) is a devastating phenomenon and reported to be complicated with systemic autoimmune disease-associated interstitial lung disease (ILD). The aim of this study was to investigate the incidence and prognosis of AE of systemic autoimmune disease-ILD and clarify relevant clinical information predictive of these outcomes.

Method

This study was designed as a systematic review and meta-analysis. A primary study except for a case report, which reported the incidence and/or prognosis of AE of systemic autoimmune disease-ILD, was eligible for the review. Electronic databases such as Medline and EMBASE were searched from 2002 through 23 February 2020. Two reviewers independently selected eligible reports and extracted relevant data. Risk of bias of individual studies was assessed similarly. The incidence and prognosis of the disease were analysed qualitatively. Univariate results of risk and prognostic factors were combined if feasible.

Results

Out of a total of 2662 records, 24 studies were eligible. A total of 420 subjects with 45.7% of men developed AE of systemic autoimmune disease-ILD and the two major underlying systemic autoimmune diseases were rheumatoid arthritis (34.2%) and polymyositis/dermatomyositis (31.9%). The frequency ranged from 4.3 to 32.9% with the incident rate being 3.19 and 5.77 per 100 patient-years and all-cause mortality was between 30.0 and 58.3% at 90 days. Age at initial presentation was significantly associated with the development of AE of systemic autoimmune disease-ILD with an HR of 1.22 (95%CI 1.05–1.50) while a percentage of predicted diffusing capacity of the lung for carbon monoxide (%DLCO) was also significantly associated with the development of the disease with an HR of 0.95 (95%CI 0.90–1.00) and an OR of 0.97 (95%CI 0.95–0.99). Partial pressure of arterial oxygen/fraction of inspired oxygen ratio (PaO₂/FiO₂) at AE was significantly associated with all-cause mortality of AE of systemic autoimmune disease-ILD with an HR of 0.99 (95%CI 0.98–0.99).

Conclusion

AE of systemic autoimmune disease-ILD was not uncommon and demonstrated dismal prognosis. Age at initial presentation and %DLCO were deemed as risk factors while PaO₂/FiO₂ at AE was considered as a prognostic factor of the disease.

Registration CRD42019138941.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01502-w.

Non-invasive diagnosis: non-alcoholic fatty liver disease and alcoholic liver disease

Non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) are becoming the leading causes of chronic liver disease worldwide, significantly impacting public health and healthcare cost. The development of fibrosis is the main factor leading to early mortality and morbidity in NAFLD and ALD. Thus, it is important to timely and reliably evaluate these diseases at early stages, when fibrosis is not advanced or when steatosis predominates. Liver biopsy has been the standard of reference for fibrosis and steatosis, however, its invasiveness precludes its widespread use. There is growing research on non-invasive methods for diagnosing and stratifying fibrosis and steatosis in NAFLD and ALD. This review presents clinical evidence on the use of non-invasive assessment of liver disease (blood-based and imaging-based) in patients with NALFD and ALD, and proposes algorithms incorporating these tests into their management.

Necrostatin-1 Alleviates Bleomycin-Induced Pulmonary Fibrosis and Extracellular Matrix Expression in Interstitial Pulmonary Fibrosis

Background

Interstitial pulmonary fibrosis (IPF) is harmful for patients’ life and health. The effective treatment of IPF is lacking because of unclear pathogenesis. Necrostatin-1 has protective effects on lung injury and can suppress the fibrosis development. I this study we investigated whether necrostatin-1 could decrease the proliferation of pulmonary fibroblasts, pulmonary fibrosis and expression of extracellular matrix (ECM) in IPF.

Material/Methods

The IPF mice model was conducted by intra-tracheal injection of bleomycin (BLM) (2 mg/kg) for C57BL/6N mice. Necrostatin-1 treatment was performed with 1 mg/kg necrostatin-1 by an intravenous injection for C57BL/6N mice. Lung tissue structures and collagen deposition were observed by hematoxylin and eosin staining and Masson staining. IPF in vitro model was constructed by MRC-5 cells induced by transforming growth factor beta 1 (TGF-β1). And, 20 μM necrostatin-1 was used to treat the TGF-β1 induced MRC-5 cells. Cell Counting Kit-8 (CCK-8) assay detected the viability of MRC-5 cells. The expression of receptor-interacting protein kinase-1 and -3 (RIPK1 and RIPK3), α smooth muscle actin (α-SMA), collagen IV, collagen I, fibronectin (FN), and transforming growth factor-β (TGF-β) in lung tissues and MRC-5 cells was measured by western blot analysis. The α-SMA expression in lung tissues was also analyzed by immunohistochemistry.

Results

The expression of RIPK1 and RIPK3 in lung tissues of BLM induced mice was increased. The degree of pulmonary fibrosis and expression of α-SMA, collagen IV, collagen I, FN, and TGF-β in lung tissues of BLM induced mice was enhanced. The proliferation of MRC-5 cells was increased when MRC-5 cells were induced by TGF-β. The expression of RIPK1, RIPK3, α-SMA, collagen IV, collagen I, and FN was increased in TGF-β induced MRC-5 cells. And, necrostatin-1 could effectively reverse the changes of pulmonary fibrosis, RIPK1, RIPK3, and ECM in vivo and in vitro experiments.

Conclusions

Necrostatin-1 attenuated pulmonary fibrosis in lung tissues of BLM induced mice and inhibited the fibroblast proliferation. And, necrostatin-1 also decreased the expression of RIPK1, RIPK3, and ECM in lung tissues of BLM induced mice and TGF-β induced fibroblasts. Necrostatin-1 could be a new effective drug for the treatment of IPF.

Circulating lung biomarkers in idiopathic lung fibrosis and interstitial lung diseases associated with connective tissue diseases: Where do we stand?

Interstitial lung diseases (ILDs) are complex diseases with various courses where personalized medicine is highly expected. Biomarkers are indicators of physiological, pathological processes or of pharmacological response to therapeutic interventions. They can be used for diagnosis, risk-stratification, prediction and monitoring of treatment response. To better delineate the input and pitfalls of biomarkers in ILDs, we performed a systematic review and meta-analysis of literature in MEDLINE and Embase databases from January 1960 to February 2019. We focused on circulating biomarkers as having the highest generalizability. Overall, 70 studies were included in the review and 20 studies could be included in the meta-analysis. This review highlights that ILD associated with connective tissue diseases (CTD-ILD) and idiopathic pulmonary fibrosis (IPF) share common biomarkers, suggesting common pathophysiological pathways. KL-6 and SP-D, could diagnose lung fibrosis in both IPF and CTD-ILD, with KL-6 having the strongest value (OR: 520.95[110.07-2465.58], p<0.001 in IPF and OR:26.43[7.15-97.68], p<0.001 in CTD-ILD), followed by SPD (OR: 33.81[3.20-357.52], p = 0.003 in IPF and 13.24 [3.84-45.71] in SSc-ILD), MMP7 appeared as interesting for IPF diagnosis (p<0.001), whereas in SSc, CCL18 was associated with ILD diagnosis. Both CCL18 and KL-6 were predictive for the outcomes of ILDs, with higher predictive values for CCL18 in both IPF (OR:10.22[4.72-22.16], p<0.001 and in SSc [2.62[1.71-4.03], p<0.001). However, disease specific biomarkers are lacking and large longitudinal studies are needed before the translational use of the potential biomarkers in clinical practice. With the recent availability of new effective therapies in ILDs, further studies should assess response to treatment.

Yangyin Yiqi Mixture Ameliorates Bleomycin-Induced Pulmonary Fibrosis in Rats through Inhibiting TGF-β1/Smad Pathway and Epithelial to Mesenchymal Transition

Objective

The aim of the current study was to investigate the protective effect of Yangyin Yiqi Mixture (YYYQ) on Bleomycin-induced pulmonary fibrosis in rats based on TGF-β1/Smad signal pathway and epithelial to mesenchymal transition (EMT).

Methods

120 Wistar rats were randomly divided into six groups: control group, BLM group, BLM + Pred group, BLM+YYYQ-L group, BLM+YYYQ-M group, and BLM+YYYQ-H group. Rats were given an intratracheal instillation of 3 mg/kg BLM to establish the pulmonary fibrosis model and followed by different dosages of YYYQ (11, 22, 44g/kg, via intragastric gavage) or prednisone soluble (4.2mg/kg, via intragastric gavage) or water. After 14 days and 28 days, tissue sections were stained with hematoxylin-eosin and Masson's trichrome to observe histopathological changes. Protein levels of TGF-β1, CTGF, Interleukin 18, and hydroxyproline were detected by ELISA method, and mRNA expressions of TGF-β1, TβRI, TβRII, Smad3, Smad7, α-SMA, E-cadherin, laminin, and collagen I were detected by RT-PCR.

Results

TGF-β1, CTGF, Interleukin 18, and hydroxyproline levels and mRNA expression of TGF-β1, TβRI, TβRII, Smad3, α-SMA, laminin, and collagen I were significantly increased (p <0.01), while Smad7 and E-cadherin levels were significantly decreased in BLM group (p <0.01). YYYQ-M and YYYQ-H group had downregulated the TGF-β1, CTGF, hydroxyproline contents, and mRNA expression of TGF-β1, TβRI, TβRII, Smad3, α-SMA, laminin, and collagen I and upregulated mRNA levels of Smad7 and E-cadherin significantly (p <0.01 or p <0.05). The result from the present study, which was also supported by histological evidence, suggested that YYYQ-M group and YYYQ-H group exhibited better treatment effect on Bleomycin-induced pulmonary fibrotic rats when compared to that of BLM + Pred group (p <0.01). Meanwhile, the effect of YYYQ, in three different dosages, on the level of interleukin 18 was not significant.

Conclusion

These results showed that YYYQ has the potential of ameliorating the progression of pulmonary fibrosis, and the mechanism may be related to suppressing TGF-β1/Smad signal pathway and EMT in BLM-induced pulmonary fibrosis of rats.