Fibrosis-related Disease Research Articles

6500 Screening Rates in Emerging Adults With Cystic Fibrosis for Cystic Fibrosis-Related Bone Disease: A Retrospective Cohort Study

6500 Screening Rates in Emerging Adults With Cystic Fibrosis for Cystic Fibrosis-Related Bone Disease: A Retrospective Cohort Study

WS14.03 May CFTR inhibition-related lipid accumulation in skeletal stem cells lead to cystic fibrosis-related bone disease?

WS14.03 May CFTR inhibition-related lipid accumulation in skeletal stem cells lead to cystic fibrosis-related bone disease?

Effects of modulator therapies on endocrine complications in adults with cystic fibrosis: a narrative review.

Cystic fibrosis is a monogenic disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) protein, which transports chloride ions in secretory organs. Modulator therapies are small molecules that correct CFTR dysfunction and can lead to a wide range of benefits for both pulmonary and extrapulmonary complications of cystic fibrosis. With advancements in airway, antimicrobial and nutritional therapies and now introduction of modulator therapies, most people living with cystic fibrosis in Australia are now adults. For adults with cystic fibrosis, endocrine manifestations such as cystic fibrosis-related diabetes, metabolic bone disease, and reproductive health are becoming increasingly important, and emerging evidence on the endocrine effects of CFTR modulator therapies is promising and is shifting paradigms in our understanding and management of these conditions. The management of cystic fibrosis-related diabetes will likely need to pivot for high responders to modulator therapy with dietary adaptions and potential use of medications traditionally reserved for adults with type 2 diabetes, but evidence to support changing clinical care needs is currently lacking. Increased attention to diabetes-related complications screening will also be required. Increased exercise capacity due to improved lung function, nutrition and potentially direct modulator effect may have a positive impact on cystic fibrosis-related bone disease, but supporting evidence to date is limited. Fertility can improve in women with cystic fibrosis taking modulator therapy. This has important implications for pregnancy and lactation, but evidence is lacking to guide pre-conception and antenatal management. Provision of multidisciplinary clinical care remains ever-important to ensure the emergence of endocrine and metabolic complications are optimised in adults with cystic fibrosis.

Targeted epigenetic silencing of UCHL1 expression suppresses collagen-1 production in human lung epithelial cells

ABSTRACT Ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) is highly expressed in smokers, but little is known about the molecular mechanism of UCHL1 in airway epithelium and its possible role in affecting extracellular matrix (ECM) remodelling in the underlying submucosa. Since cigarette smoking is a major cause of lung diseases, we studied its effect on UCHL1 expression and DNA methylation patterns in human bronchial epithelial cells, obtained after laser capture micro-dissection (LCM) or isolated from residual tracheal/main stem bronchial tissue. Targeted regulation of UCHL1 expression via CRISPR/dCas9 based-epigenetic editing was used to explore the function of UCHL1 in lung epithelium. Our results show that cigarette smoke extract (CSE) stimulated the expression of UCHL1 in vitro. The methylation status of the UCHL1 gene was negatively associated with UCHL1 transcription in LCM-obtained airway epithelium at specific sites. Treatment with a UCHL1 inhibitor showed that the TGF-β1-induced upregulation of the ECM gene COL1A1 can be prevented by the inhibition of UCHL1 activity in cell lines. Furthermore, upon downregulation of UCHL1 by epigenetic editing using CRISPR/dCas-EZH2, mRNA expression of COL1A1 and fibronectin was reduced. In conclusion, we confirmed higher UCHL1 expression in current smokers compared to non- and ex-smokers, and induced downregulation of UCHL1 by epigenetic editing. The subsequent repression of genes encoding ECM proteins suggest a role for UCHL1 as a therapeutic target in fibrosis-related disease.

Time-sequential fibroblast-to-myofibroblast transition in elastin-variable 3D hydrogel environments by collagen networks

BackgroundFibrosis plays an important role in both normal physiological and pathological phenomena as fibroblasts differentiate to myofibroblasts. The activation of fibroblasts is determined through interactions with the surrounding extracellular matrix (ECM). However, how this fibroblast-to-myofibroblast transition (FMT) is regulated and affected by elastin concentration in a three-dimensional (3D) microenvironment has not been investigated.MethodsWe developed an insoluble elastin-gradient 3D hydrogel system for long-lasting cell culture and studied the molecular mechanisms of the FMT in embedded cells by nanoflow LC–MS/MS analysis along with validation through real-time PCR and immunofluorescence staining.ResultsBy optimizing pH and temperature, four 3D hydrogels containing fibroblasts were successfully fabricated having elastin concentrations of 0, 20, 50, and 80% in collagen. At the low elastin level (20%), fibroblast proliferation was significantly increased compared to others, and in particular, the FMT was clearly observed in this condition. Moreover, through mass spectrometry of the hydrogel environment, it was confirmed that differentiation proceeded in two stages. In the early stage, calcium-dependent proteins including calmodulin and S100A4 were highly associated. On the other hand, in the late stage after several passages of cells, distinct markers of myofibroblasts were presented such as morphological changes, increased production of ECM, and increased α-SMA expression. We also demonstrated that the low level of elastin concentration induced some cancer-associated fibroblast (CAF) markers, including PDGFR-β, and fibrosis-related disease markers, including THY-1.ConclusionUsing our developed 3D elastin-gradient hydrogel system, we evaluated the effect of different elastin concentrations on the FMT. The FMT was induced even at a low concentration of elastin with increasing CAF level via calcium signaling. With this system, we were able to analyze varying protein expressions in the overall FMT process over several cellular passages. Our results suggest that the elastin-gradient system employing nonlinear optics imaging provides a good platform to study activated fibroblasts interacting with the microenvironment, where the ECM plays a pivotal role.Graphical

Management of Cystic Fibrosis-related bone disease with bisphosphonates: An audit in a tertiary care hospital in the UK

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Osteoblasts and osteoclasts generation from iPSCs to study CFTR role in cystic fibrosis-related bone disease

Osteoblasts and osteoclasts generation from iPSCs to study CFTR role in cystic fibrosis-related bone disease

Endothelial-Mesenchymal Transition (EndoMT)

EndoMT is a complex biological process in which endothelial cells lose their specific markers and acquire a mesenchymal phenotype and express mesenchymal cell products. Endo-MT has been reported to occur in fibrosis-related disease. Current study strongly supports the reality of an EndoMT phenomenon in human disease and expands its biological role beyond fibrosis. Recent studies have demonstrated that the occurrence of EndoMT is clearly associated with inflammation and EndoMT is one of the primary drivers of vascular inflammation.

Findings from a feasibility study of estradiol for hypogonadal women with cystic fibrosis-related bone disease

BackgroundAdvancements in therapies for patients with cystic fibrosis (CF) have decreased mortality, leading to increased prevalence of chronic complications including bone disease. CF-related bone disease (CFBD) is characterized by low bone mineral density (BMD) and fragility fractures. Estrogen deficiency increases bone resorption, resulting in decreased BMD that can be restored with estrogen replacement. Current CF guidelines recommend treating female hypogonadal patients with CFBD with estrogen replacement, but no prospective study has investigated the effects of estrogen supplementation on CFBD. Estrogen is known to modulate inflammatory markers and autoimmune diseases.We proposed to test the hypothesis that estrogen status plays a critical role in optimizing bone health, modulating inflammation, preserving lung function, and maximizing quality of life in premenopausal women with CF.MethodsWe planned a randomized, placebo-controlled, investigator- and patient-blinded, pilot trial with two parallel arms. Eligible subjects were women with CF 18–50 years old with hypogonadism and low BMD who were not taking systemic glucocorticoids, had not had a prior transplant, and did not have contraindications to oral estradiol. Subjects would be block randomized to receive oral estradiol or placebo for 6 months. The primary outcome was feasibility metrics. Secondary outcomes included relative changes in estradiol, bone turnover markers, lung function, inflammatory markers, and quality of life metrics. The study was funded through departmental funds.ResultsOf 233 subjects screened, 86 subjects were women with CF 18–50 years old and none were eligible for participation. Most subjects were excluded due to absent DXA report (24%), normal BMD (22%), or use of systemic estrogen (16%). Due to difficulty recruiting the planned 52 subjects, the trial was closed for recruitment and no subjects were randomized.ConclusionThis study was designed to investigate the feasibility of a safety and efficacy trial of estrogen therapy for women with CF. Unfortunately, due to eligibility criteria, the study was unable to recruit subjects. This feasibility study highlights the need for improved BMD screening in young women with CF. Future study designs may require the incorporation of a screening DXA as part of subject recruitment.Trial registrationThe study was registered on ClinicalTrials.gov (NCT03724955).

Magnesium implantation or supplementation ameliorates bone disorder in CFTR-mutant mice through an ATF4-dependent Wnt/β-catenin signaling

Magnesium metal and its alloys are being developed as effective orthopedic implants; however, the mechanisms underlying the actions of magnesium on bones remain unclear. Cystic fibrosis, the most common genetic disease in Caucasians caused by the mutation of CFTR, has shown bone disorder as a key clinical manifestation, which currently lacks effective therapeutic options. Here we report that implantation of magnesium-containing implant stimulates bone formation and improves bone fracture healing in CFTR-mutant mice. Wnt/β-catenin signaling in the bone is enhanced by the magnesium implant, and inhibition of Wnt/β-catenin by iCRT14 blocks the magnesium implant to improve fracture healing in CFTR-mutant mice. We further demonstrate that magnesium ion enters osteocytes, increases intracellular cAMP level and activates ATF4, a key transcription factor known to regulate Wnt/β-catenin signaling. In vivo knockdown of ATF4 abolishes the magnesium implant-activated β-catenin in bones and reverses the improved-fracture healing in CFTR-mutant mice. In addition, oral supplementation of magnesium activates ATF4 and β-catenin as well as enhances bone volume and density in CFTR-mutant mice. Together, these results show that magnesium implantation or supplementation may serve as a potential anabolic therapy for cystic fibrosis-related bone disease. Activation of ATF4-dependent Wnt/β-catenin signaling in osteocytes is identified as a previously undefined mechanism underlying the beneficial effect of magnesium on bone formation.

Targeted therapy for cystic fibrosis

The basic therapy of cystic fibrosis is currently aimed at slowing down the pathological processes associated with a decrease in the CFTR protein activity (cystic fibrosis transmembrane conductance regulator) in the gastrointestinal tract and the respiratory system. The pancreatic insufficiency is well compensated by replacement therapy with microsphere enzyme preparations and a high-calorie diet rich in proteins and fat. Chronic treatment of cystic fibrosis-related lung disease aims to improve the clearance of the bronchial tree, suppressing chronic bacterial infection and local chronic inflammation. However, no therapy was available to correct the defect in the gene or its product until 2012.The aim was to analyze literature on CFTR modulators, including their efficacy and safety, and assess the potential for developing new modulators to treat cystic fibrosis.Materials. The review included literature data (45 publications) on the use of CFTR modulators and international websites’ data.Results. Since the discovery of the CFTR gene in 1989, more than 2000 mutations or variants of the CFTR gene (hereinafter referred to as genetic variants) have been described. They interfere with the synthesis of the CFTR protein, its transport to the apical membrane of the cell, or disrupt its function as a channel for chloride anions. Although it is currently not possible to completely replace the mutant gene with a normal copy, small molecules have been identified that can modify the mutant CFTR protein and amend its function. The potential therapeutic measures are determined by class of the mutation. In clinical practice, pharmacological modeling of ion transport is currently possible only with the use of CFTR modulators: correctors and potentiators. The review defines these groups of drugs and describes 4 licensed CFTR modulators, including molecules of ivacaftor, lumacaftor, tezacaftor, elexacaftor. The data on the promising emerging next generation modulators and the prospects for the personalized selection of drugs using the assays on intestinal organoids are presented.

Human extrahepatic and intrahepatic cholangiocyte organoids show region-specific differentiation potential and model cystic fibrosis-related bile duct disease

The development, homeostasis, and repair of intrahepatic and extrahepatic bile ducts are thought to involve distinct mechanisms including proliferation and maturation of cholangiocyte and progenitor cells. This study aimed to characterize human extrahepatic cholangiocyte organoids (ECO) using canonical Wnt-stimulated culture medium previously developed for intrahepatic cholangiocyte organoids (ICO). Paired ECO and ICO were derived from common bile duct and liver tissue, respectively. Characterization showed both organoid types were highly similar, though some differences in size and gene expression were observed. Both ECO and ICO have cholangiocyte fate differentiation capacity. However, unlike ICO, ECO lack the potential for differentiation towards a hepatocyte-like fate. Importantly, ECO derived from a cystic fibrosis patient showed no CFTR channel activity but normal chloride channel and MDR1 transporter activity. In conclusion, this study shows that ECO and ICO have distinct lineage fate and that ECO provide a competent model to study extrahepatic bile duct diseases like cystic fibrosis.

MicroRNA-503 Targets Mothers Against Decapentaplegic Homolog 7 Enhancing Hepatic Stellate Cell Activation and Hepatic Fibrosis.

The hyper-accumulation of extracellular matrix (ECM) is the leading cause of hepatic fibrosis, and TGF-β-induced activation of hepatic stellate cells (HSCs) is the central event of hepatic fibrosis pathogenesis. The deregulation and dysfunction of miRNAs in hepatic fibrosis have been reported previously. To identify miRNA(s) playing a role in HSC activation and the underlying mechanism. We analyzed online microarray expression datasets from Gene Expression Omnibus (GEO) for differentially expressed miRNAs in hepatic fibrosis-related disease liver tissues, examined the specific effects of the candidate miRNA on TGF-β-induced HSC activation, and screened for the targets of the candidate miRNA in the TGF-β/SMAD signaling. Then, the predicted miRNA-mRNA binding, the specific effects of the target mRNA, and the dynamic effects of miRNA and mRNA on TGF-β-induced HSC activation were investigated. The miR-503 expression was upregulated in TGF-β-activated HSCs. miR-503 overexpression enhanced, while miR-503 inhibition attenuated TGF-β-induced HSC proliferation and ECM accumulation in HSCs. miR-503 targeted SMAD7 to inhibit SMAD7 expression. SMAD7 knockdown also aggravated TGF-β-induced HSC proliferation and ECM accumulation in HSCs. The effects of miR-503 overexpression on TGF-β-induced HSC activation were partially reversed by SMAD7 overexpression. In CCl4-induced hepatic fibrosis model in rats, miR-503 overexpression aggravated, whereas SMAD7 overexpression improved CCl4-induced fibrotic changes in rats' liver tissues. The effects of miR-503 overexpression on CCl4-induced fibrotic changes were partially reversed by SMAD7 overexpression. miR-503 acts on HSC activation and hepatic fibrosis through SMAD7. The miR-503/SMAD7 axis enhances HSC activation and hepatic fibrosis through the TGF-β/SMAD pathway.

P260 Elevated circulating sphingosine 1-phosphate in CFTR-F508del patients: a new biomarker leading to cystic fibrosis-related bone disease?

P260 Elevated circulating sphingosine 1-phosphate in CFTR-F508del patients: a new biomarker leading to cystic fibrosis-related bone disease?

SUN-LB72 The Relationship Between Estrogen Exposure and Bone Health in Women With Cystic Fibrosis

Patients with cystic fibrosis (CF) are at risk for cystic fibrosis-related bone disease (CFBD) characterized by low bone mineral density and fractures. Nutritional status, cystic fibrosis-related diabetes (CFRD), lung health, and sex hormone insufficiency affect CFBD. CF Foundation guidelines recommend exogenous estrogen treatment for women with CFBD and sex hormone deficiency. There is a lack of data regarding effects of exogenous estrogen supplementation on the bone health of CF women. This Emory IRB approved case-control study examined the association of estrogen on bone health in CF women. Data included demographics, sex hormone treatments, CFBD modifiers, and bone mineral density. 35 estrogen exposed subjects were matched 1:2 to 70 estrogen unexposed subjects for age, BMI, and transplant status. Statistical tests analyzed differences in bone health outcomes between the estrogen and non-estrogen exposed groups. At baseline, age, BMI, transplant status, and CFRD were not statistically different (p>0.05) between the two groups. The unexposed group had higher rates of pancreatic insufficiency (p=0.02). The exposed and unexposed subjects did not have statistically significant differences in areal bone mineral density at lumbar spine, femoral neck, or total hip (p>0.05). Our study demonstrates that there are no differences in bone mineral density at 3 different sites between estrogen exposed versus estrogen unexposed women. One limitation is that factors that may also influence bone density including vitamin D status, family history, and severity of CF mutation were not corrected for. Future longitudinal studies should determine if estrogen treatment can increase bone density over time in CF women.

SUN-337 Low Dose Ethinyl Estradiol in Women with Cystic Fibrosis Does Not Preserve Bone Mass

BACKGROUND: Cystic fibrosis-related bone disease (CFBD) affects 26% of adults with cystic fibrosis (CF). CFBD increases the risk for fractures, which in turn limits patients’ ability to effectively perform daily therapies necessary to maintain health. Factors contributing to CFBD include nutritional deficiencies, inflammation, glucocorticoid use, CF-related diabetes and untreated hypogonadism. Hypogonadism in CF is thought to be functional, although the distribution of etiologies of female hypogonadism in the modern era of CF therapies is unknown. Estrogen supplementation is commonly prescribed in the form of oral contraceptives to women with low bone mineral density (BMD). At our CF center, the average dose of ethinyl estradiol prescribed to women is 20 mcg. Recent evidence suggests that oral estrogen is ineffective for restoring bone health in women with functional hypogonadism and specifically that doses < 30 mcg oral ethinyl estradiol are inadequate. It is unknown if estradiol supplementation will restore and/or maintain BMD in women with CFBD. METHODS: The purpose of this study was to examine the skeletal health of a cross-section of premenopausal women seen at a single CF center taking 20 mcg or less of ethinyl estradiol daily (low-dose estrogen) compared to women not taking estrogen supplement. As screening for an IRB-approved intervention study, we collected health information by chart review. RESULTS: In a 12-week period, 98 women were seen in CF clinic. Of women 18 - 50 years old with CF and a documented DXA, 37 women were not taking estrogen supplement (mean age 30.8 ± 5.9 years) and 6 women were taking low-dose estrogen (mean age 30.4 ± 7.1 years). There were not statistically significant differences in other baseline characteristics known to modify CFBD. Women not taking estrogen had higher lumbar spine z-score: -0.04 ± 1.0, compared to women taking low-dose estrogen, z-score: -0.7 ±, 0.5 (p-value 0.01). Women not taking estrogen had higher BMD at the lumbar spine: 1.02 ± 0.1 g/cm2, compared to women taking low-dose estrogen: 0.95 ± 0.1 g/cm2 (p-value 0.03). Similar trends were seen at the total hip and femoral neck (p-values > 0.05). DISCUSSION: In this retrospective single-center chart review, women not taking estrogen supplement compared to women taking low-dose estrogen supplement had higher BMD. This was statistically significant at the lumbar spine, the DXA site with mostly trabecular bone. Estrogen deficiency causes trabecular bone loss, which can be restored with estrogen supplementation. These findings raise concern that low-dose estrogen supplementation for women with CF is inadequate for optimal bone accrual and may be detrimental. The ideal route and dose of estrogen supplementation for skeletal health of premenopausal women with CF still needs to be clarified. REFERENCES: CFF Patient Registry 2017; Aris JCEM 2005; Ackerman JCEM 2019; Anabtawi J CF 2019; Hughan J CF 2019

Nontuberculous mycobacterial infections in a Brazilian pediatric population: a seven-year survey

ABSTRACTThe aim of this study was to describe the frequency of nontuberculous mycobacteria (NTM) isolation and their related outcomes among pediatric patients of a Brazilian university hospital from 2012 to 2019. NTM were identified in different clinical samples by microbiological culture and molecular-based methods. NTM were isolated from 14 patients, out of whom four (27%) were infected and were treated accordingly. Two were infected with Mycobacterium avium complex (MAC), two with M. abscessus complex (MABSC) and one with M. intracellulare. Two patients had cystic fibrosis-related lung disease and improved after successful NTM eradication. One patient was HIV-positive and died. One patient had severe combined immunodeficiency (SCID)-related pneumonia and is currently being followed-up. We conclude that NTM frequency in our center was low among pediatric patients. Whether this is inherent to Brazilian patients, due to the broad coverage of the Bacille Calmette-Guérin (BCG) vaccine in Brazil, or a result of underdiagnosis remains to be elucidated.

Prevention of osteoporosis in cystic fibrosis.

The increased life span of patients with cystic fibrosis has lead to the detection of new complications. Osteopenia is present in up to 50% of adult patients with cystic fibrosis, and osteoporosis in 10-34% and can cause a difficult management problem. In children, defects in bone health become apparent generally at adolescence because of suboptimall bone peak mass achievement. Malnutrition, inflammation, vitamin D and vitamin K deficiency, altered sex hormone production, glucocorticoid therapy, and physical inactivity potentiate poor bone health. Monitoring bone mineral density and preventive care of osteoporosis are necessary from childhood to minimize cystic fibrosis-related bone disease in adult cystic fibrosis patients.

P240 Longterm monitoring of blood gases in children with cystic fibrosis - a more sensitive marker for Cystic Fibrosis-Related Lung Disease than FEV1?

P240 Longterm monitoring of blood gases in children with cystic fibrosis - a more sensitive marker for Cystic Fibrosis-Related Lung Disease than FEV1?

WS11-4 Current clinical practice in the management of cystic fibrosis-related bone disease in a regional UK adult cystic fibrosis centre

WS11-4 Current clinical practice in the management of cystic fibrosis-related bone disease in a regional UK adult cystic fibrosis centre