Nonobstructive azoospermia (NOA) is a severe and heterogeneous form of male factor infertility caused by dysfunction of spermatogenesis. Although various factors are well defined in the disruption of spermatogenesis, not all aspects due to the heterogeneity of the disorder have been determined yet. In this review, we focus on the recent findings and summarize the current data on epigenetic mechanisms such as DNA methylation and different metabolites produced during methylation and demethylation and various types of small noncoding RNAs involved in the pathogenesis of different groups of NOA.
Humans ; Azoospermia/metabolism* ; Male ; DNA Methylation/genetics* ; Epigenesis, Genetic ; Spermatogenesis/genetics* ; RNA, Small Untranslated/genetics*

Neuropsychiatric disorders arise from complex interactions between genetic and environmental factors. DNA methylation, a reversible and environmentally responsive epigenetic regulatory mechanism, serves as a crucial bridge linking environmental exposure, gene expression regulation, and neurobehavioral outcomes. During long-duration deep-space missions, astronauts face multiple stressors-including microgravity, cosmic radiation, circadian rhythm disruption, and social isolation, which can induce alterations in DNA methylation and increase the risk of neuropsychiatric disorders. Genome-wide DNA methylation research can be divided into 3 major methodological stages: Study design, sample preparation and detection, and data analysis, each of which can be applied to astronaut neuropsychiatric health monitoring. Systematic comparison of the Illumina MethylationEPIC array and whole-genome bisulfite sequencing reveals their complementary strengths in terms of genomic coverage, resolution, cost, and application scenarios: the array method is cost-effective and suitable for large-scale population studies and longitudinal monitoring, whereas sequencing provides higher resolution and coverage and is more suitable for constructing detailed methylation maps and characterizing individual variation. Furthermore, emerging technologies such as single-cell methylation sequencing, nanopore long-read sequencing, and machine-learning-based multi-omics integration are expected to greatly enhance the precision and interpretability of epigenetic studies. These methodological advances provide key support for establishing DNA-methylation-based monitoring systems for neuropsychiatric risk in astronauts and lay an epigenetic foundation for safeguarding neuropsychiatric health during future long-term deep-space missions.
DNA Methylation ; Humans ; Space Flight ; Mental Disorders/genetics* ; Epigenesis, Genetic ; Astronauts/psychology* ; Weightlessness/adverse effects* ; Epigenomics

Peri-implant diseases are characterized by the resorption of hard tissue and the inflammation of soft tissue. Epigenetics refers to alterations in the expression of genes that are not encoded in the DNA sequence, influencing diverse physiological activities, including immune response, inflammation, and bone metabolism. Epigenetic modifications can lead to tissue-specific gene expression variations among individuals and may initiate or exacerbate inflammation and disease predisposition. However, the impact of these factors on peri-implantitis remains inconclusive. To address this gap, we conducted a comprehensive review to investigate the associations between epigenetic mechanisms and peri-implantitis, specifically focusing on DNA methylation and microRNAs (miRNAs or miRs). We searched for relevant literature on PubMed, Web of Science, Scopus, and Google Scholar with keywords including "epigenetics," "peri-implantitis," "DNA methylation," and "microRNA." DNA methylation and miRNAs present a dynamic epigenetic mechanism operating around implants. Epigenetic modifications of genes related to inflammation and osteogenesis provide a new perspective for understanding how local and environmental factors influence the pathogenesis of peri-implantitis. In addition, we assessed the potential application of DNA methylation and miRNAs in the prevention, diagnosis, and treatment of peri-implantitis, aiming to provide a foundation for future studies to explore potential therapeutic targets and develop more effective management strategies for this condition. These findings also have broader implications for understanding the pathogenesis of other inflammation-related oral diseases like periodontitis.
Peri-Implantitis/genetics* ; Humans ; Epigenesis, Genetic ; DNA Methylation ; MicroRNAs/genetics*

Cellular senescence, stable cell cycle arrest that can be triggered in normal cells in response to various intrinsic and extrinsic stressors, has been highlighted as one of the most important mechanisms involved in kidney diseases. It not only serves as a fundamental biological process promoting normal organogenesis and successful wound repair but also contributes to organ dysfunction, tissue fibrosis, and the generalized aging phenotype. Moreover, senescent cells exhibit reduced regenerative capacity, which impairs renal function recovery from injuries. Importantly, senescent cells are involved in immune regulation via secreting a diverse array of proinflammatory and profibrotic factors known as senescence-associated secretory phenotype (SASP) with autocrine, paracrine, and endocrine activities. Thus, eliminating detrimental senescent cells or inhibiting SASP production holds great promise for developing innovative therapeutic strategies for kidney diseases. In this review, we summarize the current knowledge of the intricate mechanisms and hallmarks of cellular senescence in kidney diseases and emphasize novel therapeutic targets, including epigenetic regulators, G protein-coupled receptors, and lysosome-related proteins. Particularly, we highlight the recently identified senotherapeutics, which provide new therapeutic strategies for treating kidney diseases.
Humans ; Cellular Senescence/genetics* ; Kidney Diseases/pathology* ; Senescence-Associated Secretory Phenotype/physiology* ; Animals ; Epigenesis, Genetic/physiology*

The circadian clock is a highly conserved timekeeping system in organisms, which maintains physiological homeostasis by precisely regulating periodic fluctuations in gene expression. Substantial clinical and experimental evidence has established a close association between circadian rhythm disruption and the development of various malignancies. Research has revealed characteristic alterations in the circadian gene expression profiles in tumor tissues, primarily manifested as a dysfunction of core clock components (particularly circadian locomotor output cycles kaput (CLOCK) and brain and muscle ARNT-like 1 (BMAL1)) and the widespread dysregulation of their downstream target genes. Notably, CLOCK demonstrates non-canonical oncogenic functions, including epigenetic regulation via histone acetyltransferase activity and the circadian-independent modulation of cancer pathways. This review systematically elaborates on the oncogenic mechanisms mediated by CLOCK/BMAL1, encompassing multidimensional effects such as cell cycle control, DNA damage response, metabolic reprogramming, and tumor microenvironment (TME) remodeling. Regarding the therapeutic strategies, we focus on cutting-edge approaches such as chrononutritional interventions, chronopharmacological modulation, and treatment regimen optimization, along with a discussion of future perspectives. The research breakthroughs highlighted in this work not only deepen our understanding of the crucial role of circadian regulation in cancer biology but also provide novel insights for the development of chronotherapeutic oncology, particularly through targeting the non-canonical functions of circadian proteins to develop innovative anti-cancer strategies.
Humans ; ARNTL Transcription Factors/physiology* ; Neoplasms/therapy* ; CLOCK Proteins/physiology* ; Circadian Clocks/genetics* ; Animals ; Circadian Rhythm/genetics* ; Tumor Microenvironment ; Epigenesis, Genetic ; Gene Expression Regulation, Neoplastic

Dental mesenchymal stem cells (DMSCs) are pivotal for tooth development and periodontal tissue health and play an important role in tissue engineering and regenerative medicine because of their multidirectional differentiation potential and self-renewal ability. The cellular microenvironment regulates the fate of stem cells and can be modified using various optimization techniques. These methods can influence the cellular microenvironment, activate disparate signaling pathways, and induce different biological effects. "Epigenetic regulation" refers to the process of influencing gene expression and regulating cell fate without altering DNA sequences, such as histone methylation. Histone methylation modifications regulate pivotal transcription factors governing DMSCs differentiation into osteo-/odontogenic lineages. The most important sites of histone methylation in tooth organization were found to be H3K4, H3K9, and H3K27. Histone methylation affects gene expression and regulates stem cell differentiation by maintaining a delicate balance between major trimethylation sites, generating distinct chromatin structures associated with specific downstream transcriptional states. Several crucial signaling pathways associated with osteogenic differentiation are susceptible to modulation via histone methylation modifications. A deeper understanding of the regulatory mechanisms governing histone methylation modifications in osteo-/odontogenic differentiation and immune-inflammatory responses of DMSCs will facilitate further investigation of the epigenetic regulation of histone methylation in DMSC-mediated tissue regeneration and inflammation. Here is a concise overview of the pivotal functions of epigenetic histone methylation at H3K4, H3K9, and H3K27 in the regulation of osteo-/odontogenic differentiation and renewal of DMSCs in both non-inflammatory and inflammatory microenvironments. This review summarizes the current research on these processes in the context of tissue regeneration and therapeutic interventions.
Mesenchymal Stem Cells/physiology* ; Humans ; Osteogenesis/genetics* ; Histones/metabolism* ; Cell Differentiation/physiology* ; Methylation ; Odontogenesis/genetics* ; Epigenesis, Genetic

Stem cells play a crucial role in maintaining tissue regenerative capacity and homeostasis. However, mechanisms associated with stem cell senescence require further investigation. In this study, we conducted a proteomic analysis of human dental pulp stem cells (HDPSCs) obtained from individuals of various ages. Our findings showed that the expression of NUP62 was decreased in aged HDPSCs. We discovered that NUP62 alleviated senescence-associated phenotypes and enhanced differentiation potential both in vitro and in vivo. Conversely, the knocking down of NUP62 expression aggravated the senescence-associated phenotypes and impaired the proliferation and migration capacity of HDPSCs. Through RNA-sequence and decoding the epigenomic landscapes remodeled induced by NUP62 overexpression, we found that NUP62 helps alleviate senescence in HDPSCs by enhancing the nuclear transport of the transcription factor E2F1. This, in turn, stimulates the transcription of the epigenetic enzyme NSD2. Finally, the overexpression of NUP62 influences the H3K36me2 and H3K36me3 modifications of anti-aging genes (HMGA1, HMGA2, and SIRT6). Our results demonstrated that NUP62 regulates the fate of HDPSCs via NSD2-dependent epigenetic reprogramming.
Humans ; Dental Pulp/cytology* ; Nuclear Pore Complex Proteins/genetics* ; Cellular Senescence/genetics* ; Stem Cells/metabolism* ; Epigenesis, Genetic ; Cell Proliferation ; Cell Differentiation ; Histone-Lysine N-Methyltransferase/metabolism* ; Cells, Cultured ; Cellular Reprogramming ; Cell Movement ; Proteomics

Successful cloning through somatic cell nuclear transfer (SCNT) faces significant challenges due to epigenetic obstacles. Recent studies have highlighted the roles of H3K4me3 and H3K27me3 as potential contributors to these obstacles. However, the underlying mechanisms remain largely unclear. In this study, we generated genome-wide maps of H3K4me3 and H3K27me3 in mouse pre-implantation NT embryos. Our analysis revealed that aberrantly over-represented broad H3K4me3 domain and H3K27me3 signal lead to increased bivalent marks at gene promoters in NT embryos compared with naturally fertilized (NF) embryos at the 2-cell stage, which may link to relatively low levels of H3K36me3 in NT 2-cell embryos. Notably, the overexpression of Setd2, a H3K36me3 methyltransferase, successfully restored multiple epigenetic marks, including H3K36me3, H3K4me3, and H3K27me3. In addition, it reinstated the expression levels of ZGA-related genes by reestablishing H3K36me3 at gene body regions, which excluded H3K27me3 from bivalent promoters, ultimately improving cloning efficiency. These findings highlight the excessive bivalent state at gene promoters as a potent barrier and emphasize the removal of these barriers as a promising approach for achieving higher cloning efficiency.
Animals ; Mice ; Histone-Lysine N-Methyltransferase/biosynthesis* ; Histones/genetics* ; Nuclear Transfer Techniques ; Female ; Gene Expression Regulation, Developmental ; Promoter Regions, Genetic ; Epigenesis, Genetic ; Embryo, Mammalian/metabolism*

N4-acetylcytidine (ac4C), an emerging posttranscriptional RNA modification, plays a pivotal role in epigenetic regulation. Ac4C is detected not only in tRNA, rRNA, and mRNA, but also in miRNA, lncRNA, viral RNA, and even DNA. Functionally, ac4C stabilizes mRNA, enhances protein translation fidelity, and impacts various biological processes and diseases such as cancer, inflammation, immune regulation, neural diseases, osteogenic differentiation, cardiovascular diseases, viral infections, and replication. Current research primarily focuses on ac4C's roles in cancer progression and immunity, with emerging findings in gynecological diseases and reproduction. However, a comprehensive understanding of ac4C's implications in reproductive health is lacking. This review provides a historical perspective on ac4C's discovery and detection methods, elucidates its functions in reproductive development and gynecological disorders, and offers insights for further research in reproductive health. This review aims to pave the way for innovative therapeutic approaches and precise diagnostic tools tailored to this field.
Humans ; Reproductive Health ; Cytidine/genetics* ; Animals ; Female ; RNA Processing, Post-Transcriptional ; Epigenesis, Genetic ; RNA/genetics*

The quest to decipher the determinants of human longevity has intensified with the rise in global life expectancy. Long-lived individuals (LLIs), who exceed the average life expectancy while delaying age-related diseases, serve as a unique model for studying human healthy aging and longevity. Longevity is a complex phenotype influenced by both genetic and non-genetic factors. This review paper delves into the genetic, epigenetic, metabolic, immune, and environmental factors underpinning the phenomenon of human longevity, with a particular focus on LLIs, such as centenarians. By integrating findings from human longevity studies, this review highlights a diverse array of factors influencing longevity, ranging from genetic polymorphisms and epigenetic modifications to the impacts of diet and physical activity. As life expectancy grows, understanding these factors is crucial for developing strategies that promote a healthier and longer life.
Humans ; Healthy Aging/physiology* ; Longevity/physiology* ; Epigenesis, Genetic ; Life Expectancy ; Exercise ; Aging/genetics* ; Diet ; Aged, 80 and over