Relation between sex hormones and leucocyte telomere length in men with idiopathic pulmonary fibrosis

The novel molecular mechanism of pulmonary fibrosis: insight into lipid metabolism from reanalysis of single-cell RNA-seq databases

Pulmonary fibrosis (PF) is a severe pulmonary disease with limited available therapeutic choices. Recent evidence increasingly points to abnormal lipid metabolism as a critical factor in PF pathogenesis. Our latest research identifies the dysregulation of low-density lipoprotein (LDL) is a new risk factor for PF, contributing to alveolar epithelial and endothelial cell damage, and fibroblast activation. In this study, we first integrative summarize the published literature about lipid metabolite changes found in PF, including phospholipids, glycolipids, steroids, fatty acids, triglycerides, and lipoproteins. We then reanalyze two single-cell RNA-sequencing (scRNA-seq) datasets of PF, and the corresponding lipid metabolomic genes responsible for these lipids' biosynthesis, catabolism, transport, and modification processes are uncovered. Intriguingly, we found that macrophage is the most active cell type in lipid metabolism, with almost all lipid metabolic genes being altered in macrophages of PF. In type 2 alveolar epithelial cells, lipid metabolic differentially expressed genes (DEGs) are primarily associated with the cytidine diphosphate diacylglycerol pathway, cholesterol metabolism, and triglyceride synthesis. Endothelial cells are partly responsible for sphingomyelin, phosphatidylcholine, and phosphatidylethanolamines reprogramming as their metabolic genes are dysregulated in PF. Fibroblasts may contribute to abnormal cholesterol, phosphatidylcholine, and phosphatidylethanolamine metabolism in PF. Therefore, the reprogrammed lipid profiles in PF may be attributed to the aberrant expression of lipid metabolic genes in different cell types. Taken together, these insights underscore the potential of targeting lipid metabolism in developing innovative therapeutic strategies, potentially leading to extended overall survival in individuals affected by PF.

Low Serum Testosterone as a Poor Prognostic Marker in Urethral Stricture: A Single-Center Prospective Longitudinal Study

Introduction Androgens play a key role in modulating periurethral and preputial vascularity, cavernosal smooth muscle integrity, and penile growth. As a result, low testosterone may adversely affect the severity and outcome of urethral stricture patients. So, to find out the hormonal influence on the clinical outcome of urethral stricture we conducted a prospective longitudinal study at our institute. Methods The study was conducted at the Department of Urology, Institute of Post Graduate Medical Education & Research (IPGMER), Kolkata, India, from February 2023 to September 2023. This study was approved by the Institutional Ethics Committee at IPGMER, Kolkata with the approval number IPGMER/IEC/2023/436. Hormonal levels in patients with diagnosed non-traumatic urethral stricture were compared with patients without stricture. Patients with any overt hormonal abnormality or androgen-secreting tumor were excluded. A morning 10 cc blood sample was collected for testosterone, follicle-stimulating hormone, luteinizing hormone, and thyroid-stimulating hormone. The association of hormonal levels was measured in both groups and compared statistically. Any association of hypogonadism (testosterone <300 ng/dL) with respect to length, severity, and recurrence of urethral stricture was also studied. Results Forty patients with urethral stricture and same number of patients without stricture were included in the study. The mean testosterone level was found to be significantly low in patients with stricture (386 ng/dL vs 660 ng/dL). The age-wise distribution also showed low mean testosterone compared to patients without stricture. The incidence of hypogonadism is also found to be higher in stricture patients (47.5% vs 27.5%). It was also observed low testosterone is more prevalent in pan-anterior stricture (10/40) and long-segment stricture(>2 cm). Patients with stricture were also followed up for 6 months for recurrence of symptoms. Thirteen patients had recurrence. Patients with recurrence had significantly low serum testosterone (272 ng/dL vs 440 ng/dL). Conclusion Our study documented stricture patients with low serum testosterone have poor outcomes. Low testosterone level is strongly associated with longer stricture and increased risk of stricture recurrence.

Change in telomere length and cardiovascular risk factors in testicular cancer survivors

BACKGROUND

Testicular cancer (TC) survivors cured with chemotherapy (CT) are prone to develop cardiovascular diseases, as part of an accelerated aging phenotype. A mechanism contributing to these events can be telomere shortening.

PATIENTS AND METHODS

In a prospective cohort of patients with disseminated TC who received cisplatin-based CT, mean absolute leukocyte telomere length (TL) was measured before and 1 year after start of treatment. Cardiovascular risk factors, including development of the metabolic syndrome and hypogonadism, were assessed before and up to 5 years after CT.

RESULTS

For the whole group (n = 55), TL did not change 1 year after CT (5.7 (2.2-13.4) vs. 5.8 kb (1.6-19.2), P = 0.335). At baseline, patients with a BMI >30 kg/m2 (n = 12) had shorter TL (4.9 (2.2-13.4) vs. 6.3 kb (3.1-12.9), P = 0.045), while no age-dependent differences were measured. Patients with TL shortening after 1 year (n = 7) showed a significant increase in diastolic blood pressure (P = 0.007) and triglycerides (P = 0.003), compared to those with unchanged TL. There was no association between telomere shortening after 1 year or short TL at baseline (n = 7+11) and development of metabolic syndrome (25% vs. 21%; P = 0.777), or hypogonadism (38% vs. 17%; P = 0.120) after 5 years.

CONCLUSIONS

A small subset of TC patients treated with cisplatin-based CT showed telomere shortening 1 year after treatment. This shortening was associated to a rise in diastolic blood pressure and triglycerides, but not to newly developed metabolic syndrome and hypogonadism after 5 years.

No effect of danazol treatment in patients with advanced idiopathic pulmonary fibrosis

Background

Telomere dysfunction can underly the development of idiopathic pulmonary fibrosis (IPF), and recent work suggests that patients with telomere syndromes might benefit from treatment with androgens, such as danazol.

Methods

This was a prospective observational cohort study. 50 patients with IPF received off-label treatment with danazol after they showed progressive disease under treatment with pirfenidone or nintedanib. The primary outcome was the difference in yearly decline in forced vital capacity (FVC) prior to (pre) and after (post) start of treatment with danazol.

Results

There was no significant difference in FVC-decline between 1 year pre and 1 year post start of danazol treatment (mean decline pre 395 mL (95% confidence interval (CI) 290-500) compared to post 461 mL (95% CI 259-712); p=0.46; paired t-test). 11 patients (22%) were still on danazol after 1 year, and 39 patients had stopped danazol, mainly because of side-effects (56%) or death (33%). In patients who were still using danazol after 1 year, FVC-decline significantly slowed down under danazol treatment (mean pre 512 mL (95% CI 308-716) versus post 198 mL (95% CI 16-380); p=0.04). Median survival post danazol was 14.9 months (95% CI 11.0-18.8).

Conclusion

Danazol as a treatment of last resort in patients with IPF did not lead to slowing of lung function decline and was associated with significant side-effects. It remains to be determined if earlier treatment or treatment of specific patient subgroups is beneficial.

Telomere length associates with chronological age and mortality across racially diverse pulmonary fibrosis cohorts

Pulmonary fibrosis (PF) is characterized by profound scarring and poor survival. We investigated the association of leukocyte telomere length (LTL) with chronological age and mortality across racially diverse PF cohorts. LTL measurements among participants with PF stratified by race/ethnicity were assessed in relation to age and all-cause mortality, and compared to controls. Generalized linear models were used to evaluate the age-LTL relationship, Cox proportional hazards models were used for hazard ratio estimation, and the Cochran-Armitage test was used to assess quartiles of LTL. Standardized LTL shortened with increasing chronological age; this association in controls was strengthened in PF (R = -0.28; P < 0.0001). In PF, age- and sex-adjusted LTL below the median consistently predicted worse mortality across all racial groups (White, HR = 2.21, 95% CI = 1.79-2.72; Black, HR = 2.22, 95% CI = 1.05-4.66; Hispanic, HR = 3.40, 95% CI = 1.88-6.14; and Asian, HR = 2.11, 95% CI = 0.55-8.23). LTL associates uniformly with chronological age and is a biomarker predictive of mortality in PF across racial groups.

Exome sequencing link mutation in RGPD4 with systemic sclerosis-associated interstitial lung disease and the low level of testosterone—an exploration study

Background

Interstitial lung disease (ILD) is the most common and potentially most devastating manifestation of SSc in pulmonary involvement. However, the mechanism for systemic sclerosis-associated ILD (SSc-ILD) is unclear. This work aims to explore the potential candidates for SSc-ILD upon whole exome sequencing (WES) and attempts to analyze the possible pathogenesis of SSc-ILD from the perspective of the genetic level.

Materials

Variants were confirmed by whole exome sequencing (WES), and SKAT analysis was employed to explore the most differential variants. Targeted variants were performed in biological functions, associated with clinical manifestations, and the probable change of downstream.

Results

By WES and SKAT analysis of SSc with and without ILD, only the variants of RGPD4 achieved statistical power (P < 2.51 × 10^-6, P-FDR = 0.025, OR = 15.95). A total of 20 rare functional variants (missense, truncating, splicing) were tested for the RGPD4 gene, and five truncating and damaging missense variants were identified. Carriers showed the older inclusion age (P = 0.02) and the higher frequency use of prednisone (P=0.02) compared to the non-carriers. Further analysis illustrated that carriers showed lower levels of TES in comparison to non-carriers but did not reach statistical difference (P = 0.08). In bivariate correlation analysis, we analyzed the relationship between the mutant status of RGPD4 and the levels of sex hormones after adjusting for age confounders. Only the level of TES showed a negative correlation with the mutant status (B = -0.509, P = 0.037).

Conclusion

The variants of RGPD4 might contribute to the ILD development of SSc and might also be a causative factor of lower TES among SSc-ILD, which provided insight to a better understanding of pathobiology of SSc-ILD, and androgen hormone supplement might be a therapeutic target in this debilitating disease.

Evaluation of Proteasome Inhibitors in the Treatment of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is the most common form of idiopathic interstitial pneumonia, and it has a worse prognosis than non-small cell lung cancer. The pathomechanism of IPF is not fully understood, but it has been suggested that repeated microinjuries of epithelial cells induce a wound healing response, during which fibroblasts differentiate into myofibroblasts. These activated myofibroblasts express α smooth muscle actin and release extracellular matrix to promote matrix deposition and tissue remodeling. Under physiological conditions, the remodeling process stops once wound healing is complete. However, in the lungs of IPF patients, myofibroblasts re-main active and deposit excess extracellular matrix. This leads to the destruction of alveolar tissue, the loss of lung elastic recoil, and a rapid decrease in lung function. Some evidence has indicated that proteasomal inhibition combats fibrosis by inhibiting the expressions of extracellular matrix proteins and metalloproteinases. However, the mechanisms by which proteasome inhibitors may protect against fibrosis are not known. This review summarizes the current research on proteasome inhibitors for pulmonary fibrosis, and provides a reference for whether proteasome inhibitors have the potential to become new drugs for the treatment of pulmonary fibrosis.

Demystifying idiopathic interstitial pneumonia: time for more etiology-focused nomenclature in interstitial lung disease

INTRODUCTION

A major focus of interstitial lung disease (ILD) has centered on disorders termed idiopathic interstitial pneumonias (IIPs) which include, among others, idiopathic pulmonary fibrosis, idiopathic nonspecific interstitial pneumonia, cryptogenic organizing pneumonia, and respiratory bronchiolitis-interstitial lung disease.

AREAS COVERED

We review the radiologic and histologic patterns for the nine disorders classified by multidisciplinary approach as IIP, and describe the remarkable amount of published epidemiologic, translational, and molecular studies demonstrating their associations with numerous yet definitive environmental exposures, occupational exposures, pulmonary diseases, systemic diseases, medication toxicities, and genetic variants.

EXPERT OPINION

In the 21st century, these disorders termed IIPs are rarely idiopathic, but rather are well-described radiologic and histologic patterns of lung injury that are associated with a wide array of diverse etiologies. Accordingly, the idiopathic nomenclature is misleading and confusing, and may also promote a lack of inquisitiveness, suggesting the end rather than the beginning of a thorough diagnostic process to identify ILD etiology and initiate patient-centered management. A shift toward more etiology-focused nomenclature will be beneficial to all, including patients hoping for better life quality and disease outcome, general medicine and pulmonary physicians furthering their ILD knowledge, and expert ILD clinicians and researchers who are advancing the ILD field.

TELO-SCOPE study: a randomised, double-blind, placebo-controlled, phase 2 trial of danazol for short telomere related pulmonary fibrosis

Introduction

Recent discoveries have identified shortened telomeres and related mutations in people with pulmonary fibrosis (PF). There is evidence to suggest that androgens, including danazol, may be effective in lengthening telomeres in peripheral blood cells. This study aims to assess the safety and efficacy of danazol in adults and children with PF associated with telomere shortening.

Methods and analysis

A multi-centre, double-blind, placebo-controlled, randomised trial of danazol will be conducted in subjects aged >5 years with PF associated with age-adjusted telomere length ≤10th centile measured by flow fluorescence in situ hybridisation; or in children, a diagnosis of dyskeratosis congenita. Adult participants will receive danazol 800 mg daily in two divided doses or identical placebo capsules orally for 12 months, in addition to standard of care (including pirfenidone or nintedanib). Paediatric participants will receive danazol 2 mg/kg/day orally in two divided doses or identical placebo for 6 months. If no side effects are encountered, the dose will be escalated to 4 mg/kg/day (maximum 800 mg daily) orally in two divided doses for a further 6 months. The primary outcome is change in absolute telomere length in base pairs, measured using the telomere shortest length assay (TeSLA), at 12 months in the intention to treat population.

Ethics and dissemination

Ethics approval has been granted in Australia by the Metro South Human Research Ethics Committee (HREC/2020/QMS/66385). The study will be conducted and reported according to Standard Protocol Items: Recommendations for Interventional Trials guidelines. Results will be published in peer-reviewed journals and presented at international and national conferences.

Trial registration numbers

NCT04638517; Australian New Zealand Clinical Trials Registry (ACTRN12620001363976p).

Genetic, Environmental and Lifestyle Determinants of Accelerated Telomere Attrition as Contributors to Risk and Severity of Multiple Sclerosis

Telomeres are protective structures at the ends of linear chromosomes. Shortened telomere lengths (TL) are an indicator of premature biological aging and have been associated with a wide spectrum of disorders, including multiple sclerosis (MS). MS is a chronic inflammatory, demyelinating and neurodegenerative disease of the central nervous system. The exact cause of MS is still unclear. Here, we provide an overview of genetic, environmental and lifestyle factors that have been described to influence TL and to contribute to susceptibility to MS and possibly disease severity. We show that several early-life factors are linked to both reduced TL and higher risk of MS, e.g., adolescent obesity, lack of physical activity, smoking and vitamin D deficiency. This suggests that the mechanisms underlying the disease are connected to cellular aging and senescence promoted by increased inflammation and oxidative stress. Additional prospective research is needed to clearly define the extent to which lifestyle changes can slow down disease progression and prevent accelerated telomere loss in individual patients. It is also important to further elucidate the interactions between shared determinants of TL and MS. In future, cell type-specific studies and advanced TL measurement methods could help to better understand how telomeres may be causally involved in disease processes and to uncover novel opportunities for improved biomarkers and therapeutic interventions in MS.

Relation between sex hormones and leucocyte telomere length in men with idiopathic pulmonary fibrosis

Background and objective

IPF is an ageing‐related lung disorder featuring progressive lung scarring. IPF patients are frequently identified with short telomeres but coding mutations in telomerase can only explain a minority of cases. Sex hormones regulate telomerase activity in vitro and levels of sex hormones are related to LTL. The objective of this study was to explore whether sex hormones were associated with LTL, whether they interacted with genetic variants in telomerase and whether polymorphisms in the exon of androgen metabolism genes were associated with plasma testosterone concentrations in male IPF patients.

Methods

A case–control study was performed on 101 male IPF subjects and 51 age‐matched healthy controls. Early morning plasma sex hormones were quantified, and whole‐exome sequencing was used to identify rare protein‐altering variants of telomerase and SNP in the exon of androgen metabolism genes. LTL was analysed by PCR and expressed as a T/S ratio.

Results

LTL, testosterone and DHT were decreased significantly in the IPF group. After adjustments for age and variant status in telomerase‐related genes, only testosterone was positively associated with LTL (P = 0.001). No significant interaction (P = 0.661) was observed between rare protein‐altering variants of telomerase and testosterone. No coding SNP in androgen metabolism genes were significantly associated with testosterone concentrations.

Conclusion

Plasma testosterone is associated with LTL independent of age or rare protein‐altering variants of telomerase. No genetic variations of androgen‐related pathway genes are associated with androgen concentrations. Further studies are warranted to examine whether hormonal interventions might retard telomere loss in male IPF patients.