Inhibitory effects of pitavastatin on fibrogenic mediator production by human lung fibroblasts

Comorbidities in unclassifiable interstitial lung disease

BACKGROUND

Comorbidities are common in interstitial lung diseases (ILD) and have an important association with survival, but the frequency and prognostic impact of comorbidities in unclassifiable interstitial lung disease (uILD) remains elusive. We aimed to describe the prevalence of comorbidities and assess the impact on survival in patients with uILD. Furthermore, we aimed to identify and characterize potential phenotypes based on clusters of comorbidities and examine their association with disease progression and survival.

METHODS

Incident patients diagnosed with uILD were identified at two ILD referral centers in Denmark and Germany from 2003 to 2018. The diagnosis uILD was based on multidisciplinary team meetings. Clinical characteristics and comorbidities were extracted from ILD registries and patient case files. Survival analyses were performed using Cox regression analyses, disease progression was analyzed by linear mixed effects models, and clusters of comorbidities were analyzed using self-organizing maps.

RESULTS

A total of 249 patients with uILD were identified. The cohort was dominated by males (60%), former (49%) or current (15%) smokers, median age was 70 years, mean FVC was 75.9% predicted, and mean DLCO was 49.9% predicted. One-year survival was 89% and three-year survival was 73%. Eighty-five percent of the patients had ≥ 1 comorbidities, 33% had ≥ 3 comorbidities and 9% had ≥ 5 comorbidities. The only comorbidity associated with excess mortality was dyslipidemia. No association between survival and number of comorbidities or the Charlson comorbidity index was observed. Three clusters with different comorbidities profiles and clinical characteristics were identified. A significant annual decline in FVC and DLCO % predicted was observed in cluster 1 and 2, but not in cluster 3. No difference in mortality was observed between the clusters.

CONCLUSIONS

The comorbidity burden in uILD is lower than reported in other types of ILD and the impact of comorbidities on mortality needs further clarification. Three clusters with distinct comorbidity profiles were identified and could represent specific phenotypes. No difference in mortality was observed between clusters, but slower disease progression was observed in cluster 3. Better understanding of disease behavior and mortality will require further studies of subgroups of uILD with longer observation time.

LDLR dysfunction induces LDL accumulation and promotes pulmonary fibrosis

Treatments for pulmonary fibrosis (PF) are ineffective because its molecular pathogenesis and therapeutic targets are unclear. Here, we show that the expression of low-density lipoprotein receptor (LDLR) was significantly decreased in alveolar type II (ATII) and fibroblast cells, whereas it was increased in endothelial cells from systemic sclerosis-related PF (SSc-PF) patients and idiopathic PF (IPF) patients compared with healthy controls. However, the plasma levels of low-density lipoprotein (LDL) increased in SSc-PF and IPF patients. The disrupted LDL-LDLR metabolism was also observed in four mouse PF models. Upon bleomycin (BLM) treatment, Ldlr-deficient (Ldlr-/-) mice exhibited remarkably higher LDL levels, abundant apoptosis, increased fibroblast-like endothelial and ATII cells and significantly earlier and more severe fibrotic response compared to wild-type mice. In vitro experiments revealed that apoptosis and TGF-β1 production were induced by LDL, while fibroblast-like cell accumulation and ET-1 expression were induced by LDLR knockdown. Treatment of fibroblasts with LDL or culture medium derived from LDL-pretreated endothelial or epithelial cells led to obvious fibrotic responses in vitro. Similar results were observed after LDLR knockdown operation. These results suggest that disturbed LDL-LDLR metabolism contributes in various ways to the malfunction of endothelial and epithelial cells, and fibroblasts during pulmonary fibrogenesis. In addition, pharmacological restoration of LDLR levels by using a combination of atorvastatin and alirocumab inhibited BLM-induced LDL elevation, apoptosis, fibroblast-like cell accumulation and mitigated PF in mice. Therefore, LDL-LDLR may serve as an important mediator in PF, and LDLR enhancing strategies may have beneficial effects on PF.

The Effect of Cardiovascular Medications on Disease-Related Outcomes in Idiopathic Pulmonary Fibrosis: A Systematic Review and Meta-Analysis

Background: Multiple studies have revealed that idiopathic pulmonary fibrosis (IPF) patients are more at risk for cardiovascular diseases and that many IPF patients receive cardiovascular medications like statins, angiotensin-converting enzyme inhibitor (ACEI), angiotensin receptor blocker (ARB), and anticoagulants. Existing studies have reported divergent findings on the link between cardiovascular medications and fibrotic disease processes. The aim of this study is to synthesize the evidence on the efficacy of cardiovascular medications in IPF. Methods: We searched studies reporting the effect of cardiovascular medications on IPF in the PubMed, Embase, Web of Science, Cochrane Library, and two Chinese databases (China National Knowledge Infrastructure database and China Wanfang database). We calculated survival data, forced vital capacity (FVC) decline, and IPF-related mortality to assess the efficacy of cardiovascular medications in IPF. We also estimated statistical heterogeneity by using I² and Cochran Q tests, and publication bias was evaluated by risk of bias tools ROBINS-I. Results: A total of 12 studies were included in the analysis. The included studies had moderate-to-serious risk of bias. Statin use was associated with a reduction in mortality (hazard ratio (HR), 0.89; 95% CI 0.83-0.97). Meta-analysis did not demonstrate any significant relationship between statin use and the FVC decline (HR, 0.86; 95% CI 0.73-1.02), ACEI/ARB use, and survival data (HR, 0.92; 95% CI 0.73-1.15) as well as anticoagulant use and survival data (HR, 1.16; 95% CI 0.62-2.19). Conclusion: Our study suggested that there is a consistent relationship between statin therapy and survival data in IPF population. However, there is currently insufficient evidence to conclude the effect of ACEI, ARB, and anticoagulant therapy on IPF population especially to the disease-related outcomes in IPF.

Liver stiffness across different chronic liver disease under therapy with statin in a real life cohort

INTRODUCTION

Statins have been associated with improved clinical outcomes in patients with viral hepatitis and after variceal bleeding. Still, the clinical benefit of statins is not well defined for different liver diseases. Moreover, associations between statin use and liver stiffness as well as event free survival have not been established.

METHODS

Liver stiffness was evaluated in 6490 patients with liver disease (January 2012 till December 2016). Two hundred thirty-four of those received statin therapy, 468 controls without statins were selected by a 1:2 case by case matching using age, sex, underlying liver disease and BMI.

RESULTS

Statins were given to 234 patients with chronic virus hepatitis (n = 104), nonalcoholic fatty liver disease (n = 52), autoimmune liver disease including autoimmune hepatitis, primary biliary cholangitis and primary sclerosing cholangitis (n = 31) and hepatitis of unknown origin (n = 47). Follow-up data were available for 96 and 119 pairs (mean follow-up 2 years). Statin users showed reduced inflammatory activity. Elevated liver enzymes were reported in 57% of statin-treated compared with 70% of controls (mean alanine aminotransferase level 53 vs. 74 U/l; P < 0.001). Statin use was well tolerated in this cohort. Mean liver stiffness values were 10.7 kPa (SEM 0.7) and 15.5 kPa (SEM 0.7) accordingly (P < 0.0001). Decompensation was less likely to occur in the statin group, both groups do not defer in the incidence of liver tumor occurrence, transplantation or death (odds ratio = 1, P = nonsignificant).

CONCLUSIONS

Use of statins was well tolerated irrespective of liver disease. Statin users showed reduced hepatic inflammatory activity, less severe markers of liver stiffness and portal hypertension. There might be a beneficial effect of statin on the risk to experience hepatic decompensation.

Screening for YAP Inhibitors Identifies Statins as Modulators of Fibrosis

Idiopathic pulmonary fibrosis is a lung disease with limited therapeutic options that is characterized by pathological fibroblast activation and aberrant lung remodeling with scar formation. YAP (Yes-associated protein) is a transcriptional coactivator that mediates mechanical and biochemical signals controlling fibroblast activation. In this study, we developed a high-throughput small-molecule screen for YAP inhibitors in primary human lung fibroblasts. Multiple HMG-CoA (hydroxymethylglutaryl-coenzyme A) reductase inhibitors (statins) were found to inhibit YAP nuclear localization via induction of YAP phosphorylation, cytoplasmic retention, and degradation. We further show that the mevalonate pathway regulates YAP activation, and that simvastatin treatment reduces fibrosis markers in activated human lung fibroblasts and in the bleomycin mouse model of pulmonary fibrosis. Finally, we show that simvastatin modulates YAP in vivo in mouse lung fibroblasts. Our results highlight the potential of small-molecule screens for YAP inhibitors and provide a mechanism for the antifibrotic activity of statins in idiopathic pulmonary fibrosis.

Mesenchymal Stem Cells Loaded with Gelatin Microcryogels Attenuate Renal Fibrosis. Biomed Res Int. 2019;2019:6749326. [PMID: 31781634 PMCID: PMC6875199 DOI: 10.1155/2019/6749326]

Background

The treatment of chronic kidney diseases (CKDs) by different approaches using mesenchymal stem cells (MSCs) has made great strides. In this study, we aimed to explore the potential mechanism of gelatin microcryogels (GMs) as a cell therapeutic vector to block the progression of CKD.

Methods

In vivo, the pedicled omentum valve with MSC-loaded GMs was packed onto 5/6 nephrectomized kidneys derived from rats. The therapeutic effects were evaluated. In vitro, TNF-α, TGF-β, and MSCs were added to the medium of the HK-2 cell culture system, and key genes involved in anti-inflammatory and antifibrosis effects were evaluated by qPCR.

Results

After 12 weeks of MSC transplantation, kidney functions, such as serum creatinine, urea nitrogen, and 24-hour urine protein, were significantly improved. The pedicled omentum valve was packed with MSC-loaded GMs onto the 5/6 nephrectomized kidney, and the expressions of collagen IV, α-SMA, and TGF-β were all evaluated by immunohistochemical staining and western blot analysis. MSC-loaded-GMs also showed antifibrotic effects by inducing the upregulation of HO-1, BMP-7, and HGF and the downregulation of MCP-1 at the mRNA level. Four weeks after MSC-loaded GM treatment, we found that the mRNA levels of TNF-α and IL-6 were clearly reduced. MSC-conditional medium (MSC-CM) showed that the TNF-α-induced expression of IL-8 and IL-6 mRNA was reversed; E-cadherin mRNA was upregulated; and the TGF-β-induced expression of collagen IV, α-SMA, and fibronectin (FN) mRNA in HK-2 cells was reduced.

Conclusions

We demonstrated that the pedicled omentum valve packed with MSC-loaded GMs had a renal protective effect on the 5/6 nephrectomized kidney by observing the anti-inflammatory and antifibrosis effects.

The Effects of Epigallocatechin Gallate (EGCG) on Pulmonary Fibroblasts of Idiopathic Pulmonary Fibrosis (IPF)-A Next-Generation Sequencing and Bioinformatic Approach

Idiopathic pulmonary fibrosis (IPF) is a disabling and lethal chronic progressive pulmonary disease. Epigallocatechin gallate (EGCG) is a polyphenol, which is the major biological component of green tea. The anti-oxidative, anti-inflammatory, and anti-fibrotic effects of EGCG have been shown in some studies, whereas its effects in altering gene expression in pulmonary fibroblasts have not been systematically investigated. This study aimed to explore the effect of EGCG on gene expression profiles in fibroblasts of IPF. The pulmonary fibroblasts from an IPF patient were treated with either EGCG or water, and the expression profiles of mRNAs and microRNAs were determined by next-generation sequencing (NGS) and analyzed with the bioinformatics approach. A total of 61 differentially expressed genes and 56 differentially expressed microRNAs were found in EGCG-treated IPF fibroblasts. Gene ontology analyses revealed that the differentially expressed genes were mainly involved in the biosynthetic and metabolic processes of cholesterol. In addition, five potential altered microRNA-mRNA interactions were found, including hsa-miR-939-5p-PLXNA4, hsa-miR-3918-CTIF, hsa-miR-4768-5p-PDE5A, hsa-miR-1273g-3p-VPS53, and hsa-miR-1972-PCSK9. In summary, differentially expressed genes and microRNAs in response to EGCG treatment in IPF fibroblasts were identified in the current study. Our findings provide a scientific basis to evaluate the potential benefits of EGCG in IPF treatment, and warrant future studies to understand the role of molecular pathways underlying cholesterol homeostasis in the pathogenesis of IPF.

Effect of statins on disease-related outcomes in patients with idiopathic pulmonary fibrosis

BACKGROUND

Data are conflicting regarding the possible effects of statins in patients with idiopathic pulmonary fibrosis (IPF). This post hoc analysis assessed the effects of statin therapy on disease-related outcomes in IPF.

METHODS

Patients randomised to placebo (n=624) in three controlled trials of pirfenidone in IPF (CAPACITY 004 and 006, ASCEND) were categorised by baseline statin use. Outcomes assessed during the 1-year follow-up included disease progression, mortality, hospitalisation and composite outcomes of death or ≥10% absolute decline in FVC and death or ≥50 m decline in 6-minute walk distance (6MWD).

RESULTS

At baseline, 276 (44%) patients were statin users versus 348 (56%) non-users. Baseline characteristics were similar between groups, except statin users were older and had higher prevalence of cardiovascular disease and risk factors. In multivariate analyses adjusting for differences in baseline characteristics, statin users had lower risks of death or 6MWD decline (HR 0.69; 95% CI 0.48 to 0.99, p=0.0465), all-cause hospitalisation (HR 0.58; 95% CI 0.35 to 0.94, p=0.0289), respiratory-related hospitalisation (HR 0.44; 95% CI 0.25 to 0.80, p=0.0063) and IPF-related mortality (HR 0.36; 95% CI 0.14 to 0.95, p=0.0393) versus non-users. Non-significant treatment effects favouring statin use were observed for disease progression (HR 0.75; 95% CI 0.52 to 1.07, p=0.1135), all-cause mortality (HR 0.54; 95% CI 0.24 to 1.21, p=0.1369) and death or FVC decline (HR 0.71; 95% CI 0.48 to 1.07, p=0.1032).

CONCLUSIONS

This post hoc analysis supports the hypothesis that statins may have a beneficial effect on clinical outcomes in IPF. Prospective clinical trials are required to validate these observations.

TRIAL REGISTRATION NUMBERS

NCT01366209, NCT00287729 and NCT00287716.

Effects of rapamycin against paraquat-induced pulmonary fibrosis in mice

BACKGROUND AND AIMS

Ingestion of paraquat (PQ), a widely used herbicide, can cause severe toxicity in humans, leading to a poor survival rate and prognosis. One of the main causes of death by PQ is PQ-induced pulmonary fibrosis, for which there are no effective therapies. The aim of this study was to evaluate the effects of rapamycin (RAPA) on inhibiting PQ-induced pulmonary fibrosis in mice and to explore its possible mechanisms.

METHODS

Male C57BL/6J mice were exposed to either saline (control group) or PQ (10 mg/kg body weight, intraperitoneally; test group). The test group was divided into four subgroups: a PQ group (PQ-exposed, non-treated), a PQ+RAPA group (PQ-exposed, treated with RAPA at 1 mg/kg intragastrically), a PQ+MP group (PQ-exposed, treated with methylprednisolone (MP) at 30 mg/kg intraperitoneally), and a PQ+MP+RAPA group (PQ-exposed, treated with MP at 30 mg/kg intraperitoneally and with RAPA at 1 mg/kg intragastrically). The survival rate and body weight of all the mice were recorded every day. Three mice in each group were sacrificed at 14 d and the rest at 28 d after intoxication. Lung tissues were excised and stained with hematoxylin-eosin (H&E) and Masson's trichrome stain for histopathological analysis. The hydroxyproline (HYP) content in lung tissues was detected using an enzyme-linked immunosorbent assay (ELISA) kit. The expression of transforming growth factor-β1 (TGF-β1) and α-smooth muscle actin (α-SMA) in lung tissues was detected by immunohistochemical staining and Western blotting.

RESULTS

A mice model of PQ-induced pulmonary fibrosis was established. Histological examination of lung tissues showed that RAPA treatment moderated the pathological changes of pulmonary fibrosis, including alveolar collapse and interstitial collagen deposition. HYP content in lung tissues increased soon after PQ intoxication but had decreased significantly by the 28th day after RAPA treatment. Immunohistochemical staining and Western blotting showed that RAPA treatment significantly down-regulated the enhanced levels of TGF-β1 and α-SMA in lung tissues caused by PQ exposure. However, RAPA treatment alone could not significantly ameliorate the lower survival rate and weight loss of treated mice. MP treatment enhanced the survival rate, but had no significant effects on attenuating PQ-induced pulmonary fibrosis or reducing the expression of TGF-β1 and α-SMA.

CONCLUSIONS

This study demonstrates that RAPA treatment effectively suppresses PQ-induced alveolar collapse and collagen deposition in lung tissues through reducing the expression of TGF-β1 and α-SMA. Thus, RAPA has potential value in the treatment of PQ-induced pulmonary fibrosis.

Simvastatin impairs the induction of pulmonary fibrosis caused by a western style diet: a preliminary study

The role of an atherogenic diet in causing pulmonary fibrosis has received little attention and simvastatin has been shown to reduce pulmonary fibrosis in animal models. To determine if an atherogenic diet can induce pulmonary fibrosis and whether simvastatin treatment is beneficial by up-regulating heat shock protein 70 and 90. New Zealand white rabbits (n = 15) were divided: Group 1 (control); Group 2 (MC) received a normal rabbit diet with 1% methionine plus 0.5% cholesterol (atherogenic diet). Group 3 received the same diet as the MC group plus 5 mg/kg/day simvastatin orally (MCS). After 4 weeks, the lungs were collected and analysed. Picrosirus red staining of lung interstitial collagen content showed that the atherogenic diet increased fibrosis 2.9-fold (P < 0.05), bronchiole adventitial collagen was increased 2.3-fold (P < 0.05) and bronchiole epithelium was increased 34-fold (P < 0.05), and simvastatin treatment severely reduced this effect (P < 0.05). Western blot analysis showed that the atherogenic diet significantly reduced lung Hsp70 protein by 22% (P < 0.05) and Hsp90 protein by 18% (P < 0.05) and simvastatin treatment did not affect this result. However, aortic hyper-responsiveness to vasoconstrictors (angiotensin II and phenylephrine) were markedly reduced by simvastatin treatment. We report that an atherogenic diet stimulates pulmonary fibrosis and reduces lung Hsp70/Hsp90 protein concentration. Simvastatin impairs this by mechanisms unrelated to Hsp70/Hsp90, but possibly a reduction in angiotensin II receptor or alpha adrenergic receptor pathways. These results could have implications in idiopathic pulmonary fibrosis.

Fasudil, an inhibitor of Rho-associated coiled-coil kinase, attenuates hyperoxia-induced pulmonary fibrosis in neonatal rats

BACKGROUND

Oxygen therapy is important during the management of high-risk neonatal infants, such as those with preterm birth, low birth weight, and asphyxia. However, prolonged exposure to high oxygen concentrations can readily lead to diffuse nonspecific inflammation, which promotes airway remodeling and pulmonary fibrosis. The Rho/Rho-associated coiled-coil kinase (Rho/ROCK) signaling pathway plays an important role in numerous developmental and proliferative diseases. This study was performed to determine the efficacy of ROCK inhibitor fasudil in blocking the development of hyperoxia-induced lung injury and fibrosis in neonatal rats.

METHODS

Neonatal rats were randomly divided into four groups: air + saline group, air + fasudil group, hyperoxia + saline group, and hyperoxia + fasudil group. The hyperoxia + saline and Hyp + fasudil groups were exposed to 95% oxygen for 21 days and administered intraperitoneal saline or fasudil once daily. The air + saline and air + fasudil group were exposed to 21% oxygen (room air) and administered the same volume of intraperitoneal saline or fasudil.

RESULTS

Fasudil-treated rats exhibited improved histopathological changes and decreased lung hydroxyproline content. Fasudil attenuated the protein level of alpha-smooth muscle actin, transforming growth factor-β1, and connective tissue growth factor. Additionally, fasudil reduced the activation of ROCK1 and myosin phosphatase targeting subunit 1 protein in the Rho/ROCK signaling pathway.

CONCLUSIONS

Fasudil may be a potentially effective therapeutic drug for hyperoxia-induced pulmonary fibrosis.

Beyond TGFβ--novel ways to target airway and parenchymal fibrosis

Within the lungs, fibrosis can affect both the parenchyma and the airways. Fibrosis is a hallmark pathological change in the parenchyma in patients with idiopathic pulmonary fibrosis (IPF), whilst in asthma or chronic obstructive pulmonary disease (COPD) fibrosis is a component of the remodelling of the airways. In the past decade, significant advances have been made in understanding the disease behaviour and pathogenesis of parenchymal and airway fibrosis and as a result a variety of novel therapeutic targets for slowing or preventing progression of these fibrotic changes have been identified. This review highlights a number of these targets and discusses the potential for treating parenchymal or airway fibrosis through these mediators/pathways in the future.