Epigenetics Approaches toward Precision Medicine for Idiopathic Pulmonary Fibrosis: Focus on DNA Methylation

A particle of concern: explored and proposed underlying mechanisms of microplastic-induced lung damage and pulmonary fibrosis

PURPOSE

In the past decade, microplastics (MPs) have drawn significant attention as widespread environmental contaminants, with research increasingly highlighting their harmful effects on respiratory health in aquatic and terrestrial organisms. Findings revealed microplastics in human lung tissues, raising concerns about their potential role in damaging lung tissue integrity and contributing to pulmonary fibrosis-a chronic inflammatory condition characterized by scarring of lung epithelial tissues due to accumulated extracellular matrix, triggered by factors such as alcohol, pathogens, genetic mutations, and environmental pollutants.

OBJECTIVE

In this review, we explore both well-studied and lesser-studied mechanisms and signaling pathways, aiming to shed light on how microplastics might act as mediators that activate distinct, often overlooked signaling cascades.

MATERIALS AND METHODS

This review searched PubMed and Google Scholar using keywords like "plastic," "microplastic," "lung fibrosis," "pulmonary system," "exposure route," and "signaling pathways," combined with "OR" and "AND" in singular and plural forms.

RESULTS

These pathways could not only induce lung damage but also play a significant role in the development of pulmonary fibrosis.

DISCUSSION AND CONCLUSIONS

These signaling pathways could also be targeted to reduce microplastic-induced pulmonary fibrosis, opening new avenues for future treatments.

ULK1 methylation promotes TGF-β1-induced endometrial fibrosis via the FOXP1/DNMT1 axis

Intrauterine adhesion (IUA) is the second most common cause of secondary infertility in women and can also lead to menstrual abnormalities and multiple adverse pregnancy outcomes. Therefore, elucidating the mechanism of its development is crucial for the prevention and treatment of IUA. This study will investigate the function and mechanism of forkhead box P1 (FOXP1)/DNA methyltransferase 1 (DNMT1)/unc-51-like autophagy activating kinase 1 (ULK1) in IUA. Expression levels of key genes were detected using western blot and quantitative - real time reverse transcription polymerase chain reaction. Cell proliferation was detected by CCK-8 and EdU staining. Transcriptional regulation relationships were detected by dual luciferase reporter gene and chromatin immunoprecipitation (ChIP) assay. Methylation station of ULK1 was detected by methylmion specific PCR (MSP). Fibrosis and pathological changes in the uterine cavity tissues were detected by Masson and hematoxylin and eosin staining. It was observed that the expression of FOXP1 and DNMT1 increased in transforming growth factor (TGF)-β1-induced cells, while ULK1 expression decreased. Downregulation of FOXP1 could inhibit human endometrial stromal cells proliferation and autophagy, as well as decrease the expression of fibrogenic factors (collagen type I alpha 1 chain [COL1A1], fibronectin [FN], and alpha-smooth muscle actin [α-SMA]). The results of MSP and ChIP experiments showed that DNMT1 promotes methylation of the ULK1 promoter region and inhibits its transcription. In an animal model, knockdown of FOXP1 alleviated pathological fibrosis and uterine adhesions. Knockdown of FOXP1 can inhibit endometrial fibrosis in IUA rats; FOXP1 could be a potential target for the treatment of IUA.

Inflammatory tissue priming: novel insights and therapeutic opportunities for inflammatory rheumatic diseases

Due to optimised treatment strategies and the availability of new therapies during the last decades, formerly devastating chronic inflammatory diseases such as rheumatoid arthritis or systemic sclerosis (SSc) have become less menacing. However, in many patients, even state-of-the-art treatment cannot induce remission. Moreover, the risk for flares strongly increases once anti-inflammatory therapy is tapered or withdrawn, suggesting that underlying pathological processes remain active even in the absence of overt inflammation. It has become evident that tissues have the ability to remember past encounters with pathogens, wounds and other irritants, and to react more strongly and/or persistently to the next occurrence. This priming of the tissue bears a paramount role in defence from microbes, but on the other hand drives inflammatory pathologies (the Dr Jekyll and Mr Hyde aspect of tissue adaptation). Emerging evidence suggests that long-lived tissue-resident cells, such as fibroblasts, macrophages, long-lived plasma cells and tissue-resident memory T cells, determine inflammatory tissue priming in an interplay with infiltrating immune cells of lymphoid and myeloid origin, and with systemically acting factors such as cytokines, extracellular vesicles and antibodies. Here, we review the current state of science on inflammatory tissue priming, focusing on tissue-resident and tissue-occupying cells in arthritis and SSc, and reflect on the most promising treatment options targeting the maladapted tissue response during these diseases.

Epigenetic modification: A novel insight into diabetic wound healing

Wound healing is an intricate and fine regulatory process. In diabetic patients, advanced glycation end products (AGEs), excessive reactive oxygen species (ROS), biofilm formation, persistent inflammation, and angiogenesis regression contribute to delayed wound healing. Epigenetics, the fast-moving science in the 21st century, has been up to date and associated with diabetic wound repair. In this review, we go over the functions of epigenetics in diabetic wound repair in retrospect, covering transcriptional and posttranscriptional regulation. Among these, we found that histone modification is widely involved in inflammation and angiogenesis by affecting macrophages and endothelial cells. DNA methylation is involved in factors regulation in wound repair but also affects the differentiation phenotype of cells in hyperglycemia. In addition, noncodingRNA regulation and RNA modification in diabetic wound repair were also generalized. The future prospects for epigenetic applications are discussed in the end. In conclusion, the study suggests that epigenetics is an integral regulatory mechanism in diabetic wound healing.

The Role of Hydrogen Sulfide (H2S) in Epigenetic Regulation of Neurodegenerative Diseases: A Systematic Review

This review explores the emerging role of hydrogen sulfide (H2S) in modulating epigenetic mechanisms involved in neurodegenerative diseases. Accumulating evidence has begun to elucidate the multifaceted ways in which H2S influences the epigenetic landscape and, subsequently, the progression of various neurodegenerative disorders, including Alzheimer's, Parkinson's, and Huntington's disease. H2S can modulate key components of the epigenetic machinery, such as DNA methylation, histone modifications, and non-coding RNAs, impacting gene expression and cellular functions relevant to neuronal survival, inflammation, and synaptic plasticity. We synthesize recent research that positions H2S as an essential player within this intricate network, with the potential to open new therapeutic avenues for these currently incurable conditions. Despite significant progress, there remains a considerable gap in our understanding of the precise molecular mechanisms and the potential therapeutic implications of modulating H2S levels or its downstream targets. We conclude by identifying future directions for research aimed at exploiting the therapeutic potential of H2S in neurodegenerative diseases.

Histologic Analysis of Idiopathic Pulmonary Fibrosis by Morphometric and Fractal Analysis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrotic lung disorder, ultimately leading to respiratory failure and death. Despite great research advances in understanding the mechanisms underlying the disease, its diagnosis, and its treatment, IPF still remains idiopathic without known biological or histological markers able to predict disease progression or response to treatment. The histologic hallmark of IPF is usual interstitial pneumonia (UIP), with its intricate architectural distortion and temporal inhomogeneity. We hypothesize that normal lung alveolar architecture can be compared to fractals, such as the Pythagoras tree with its fractal dimension (D_f), and every pathological insult, distorting the normal lung structure, could result in D_f variations. In this study, we aimed to assess the UIP histologic fractal dimension in relationship to other morphometric parameters in newly diagnosed IPF patients and its possible role in the prognostic stratification of the disease. Clinical data and lung tissue specimens were obtained from twelve patients with IPF, twelve patients with non-specific interstitial pneumonia (NSIP), and age-matched "healthy" control lung tissue from patients undergoing lung surgery for other causes. Histology and histomorphometry were performed to evaluate D_f and lacunarity measures, using the box counting method on the FracLac ImageJ plugin. The results showed that D_f was significantly higher in IPF patients compared to controls and fibrotic NSIP patients, indicating greater architectural distortion in IPF. Additionally, high D_f values were associated with higher fibroblastic foci density and worse prognostic outcomes in IPF, suggesting that D_f may serve as a potential novel prognostic marker for IPF. The scalability of D_f measurements was demonstrated through repeated measurements on smaller portions from the same surgical biopsies, which were selected to mimic a cryobiopsy. Our study provides further evidence to support the use of fractal morphometry as a tool for quantifying and determining lung tissue remodeling in IPF, and we demonstrated a significant correlation between histological and radiological D_f in UIP pattern, as well as a significant association between D_f and FF density. Furthermore, our study demonstrates the scalability and self-similarity of D_f measurements across different biopsy types, including surgical and smaller specimens.