Aging ; Humans ; Presbycusis ; genetics

Recent research efforts have provided compelling evidence of genome-wide DNA methylation alterations in pediatrics. It is currently well established that epigenetic clocks, composed of DNA methylation sites, can estimate the gestational and chronological age of cells and tissues from different ages. Also, extensive research is aimed at their correlation with early life exposure and pediatric diseases. This review aimed to systematically summarize the epigenetic clocks in the pediatric population. Publications were collected from PubMed and Web of Science databases up to Apr 2021. Epigenetic clocks, DNA methylation clocks, epigenetic age acceleration or deceleration, pediatric and the pediatric population were used as search criteria. Here, we first review the currently applicative pediatric epigenetic clocks. We then highlight the interpretation for epigenetic age deviations in the pediatric population and their association with external factors, developmental trajectories, and pediatric diseases. Considering the remaining unknown of pediatric clocks, research strategies into them are also discussed. In all, pediatric epigenetic clocks may act as potent tools to understand development, growth and diseases in early life.
Aging ; Child ; DNA Methylation/genetics* ; Epigenesis, Genetic/genetics* ; Epigenomics ; Humans

Aging ; Cellular Senescence ; Heterochromatin ; Humans ; Sirtuins ; genetics ; Stem Cells

Aging ; Cardiovascular Diseases/genetics* ; Clonal Hematopoiesis ; Humans ; Mutation

The progress of epigenetic research has led to the discovery and confirmation of age-related markers based on DNA methylation. These DNA methylation indices are called "epigenetic clock/age". The concept of "epigenetic clock/age" and the establishment of its evaluation system are helpful to solve some of the long-standing problems in the field of life and medicine. When facing the current global aging, it is of great significance to refer to the comprehensive health parameters to determine the biological age and life span of an individual, and thus to design a plan to slow down the process of life cycle. This paper has summarized the concept and development of "epigenetic clock/age" in recent years.
Aging/genetics* ; Biomarkers ; DNA Methylation ; Epigenesis, Genetic ; Humans

The sirtuin proteins constitute class III histone deacetylases (HDACs). These evolutionarily conserved NAD(+)-dependent enzymes form an important component in a variety of cellular and biological processes with highly divergent as well as convergent roles in maintaining metabolic homeostasis, safeguarding genomic integrity, regulating cancer metabolism and also inflammatory responses. Amongst the seven known mammalian sirtuin proteins, SIRT1 has gained much attention due to its widely acknowledged roles in promoting longevity and ameliorating age-associated pathologies. The contributions of other sirtuins in the field of aging are also gradually emerging. Here, we summarize some of the recent discoveries in sirtuins biology which clearly implicate the functions of sirtuin proteins in the regulation of premature cellular senescence and accelerated aging. The roles of sirtuins in various cellular processes have been extrapolated to draw inter-linkage with anti-aging mechanisms. Also, the latest findings on sirtuins which might have potential effects in the process of aging have been reviewed.
Aging, Premature ; enzymology ; genetics ; Animals ; Humans ; Longevity ; genetics ; Sirtuin 1 ; genetics ; metabolism

Down syndrome is caused by partial or complete triplication of genes located on chromosome 21. Its incidence increases dramatically with the age of women. Hypotheses proposed for this have included abnormal homologous recombination, defective spindle assembly, biological aging, reduction of cohesion complexes, endocrine disorders, oocyte selection model, and single nucleotide polymorphisms of genes that maintain chromosome stability, etc. A literature review is provided here.
Aging ; genetics ; Chromosomes, Human, Pair 21 ; genetics ; Down Syndrome ; genetics ; Female ; Humans ; Maternal Age ; Oocytes ; metabolism ; Polymorphism, Single Nucleotide ; genetics

Sarcopenia is an age-related degenerative disease, in which skeletal muscle mass and function are reduced during aging process. Physical intervention is one of the most effective strategies available for the treatment of sarcopenia. Studies have shown that microRNAs (miRNAs), as important regulators of gene expression, play an important role in maintaining the homeostasis of senescent skeletal muscle cells by regulating skeletal muscle cell development (proliferation and differentiation), mitochondrial biogenesis, protein synthesis and degradation, inflammatory response and metabolic pathways. Furthermore, exercise can combat age-related changes in muscle mass, composition and function, which is associated with the changes in the expression and biological functions of miRNAs in skeletal muscle cells. In this article, we systematically review the regulatory mechanisms of miRNAs in skeletal muscle aging, and discuss the regulatory roles and molecular targets of exercise-mediated miRNAs in muscular atrophy during aging process, which may provide novel insights into the prevention and treatment of sarcopenia.
Aging/genetics* ; Exercise Therapy ; Humans ; MicroRNAs/genetics* ; Muscle, Skeletal ; Sarcopenia/therapy*

The testis is pivotal for male reproduction, and its progressive functional decline in aging is associated with infertility. However, the regulatory mechanism underlying primate testicular aging remains largely elusive. Here, we resolve the aging-related cellular and molecular alterations of primate testicular aging by establishing a single-nucleus transcriptomic atlas. Gene-expression patterns along the spermatogenesis trajectory revealed molecular programs associated with attrition of spermatogonial stem cell reservoir, disturbed meiosis and impaired spermiogenesis along the sequential continuum. Remarkably, Sertoli cell was identified as the cell type most susceptible to aging, given its deeply perturbed age-associated transcriptional profiles. Concomitantly, downregulation of the transcription factor Wilms' Tumor 1 (WT1), essential for Sertoli cell homeostasis, was associated with accelerated cellular senescence, disrupted tight junctions, and a compromised cell identity signature, which altogether may help create a hostile microenvironment for spermatogenesis. Collectively, our study depicts in-depth transcriptomic traits of non-human primate (NHP) testicular aging at single-cell resolution, providing potential diagnostic biomarkers and targets for therapeutic interventions against testicular aging and age-related male reproductive diseases.
Animals ; Male ; Testis ; Sertoli Cells/metabolism* ; Transcriptome ; Spermatogenesis/genetics* ; Primates ; Aging/genetics* ; Stem Cells

Age estimation is of great significance in the fields of criminal investigation and forensic identification. It can provide the age information of individuals to judicial departments to facilitate the development of judicial work. In recent years, age estimation methods expanded from the morphological level to the molecular biology level. With the rapid development of epigenetics represented by DNA methylation, and the advancement of DNA methylation detection technology together with the detection platform, many age estimation methods based on DNA methylation biomarkers, or using several biological fluids, such as blood, blood stains, saliva, semen stains, etc. are developed. Currently, researches related to age estimation based on DNA methylation are relatively widely carried out. This paper summarizes the researches on age estimation based on DNA methylation, in order to provide references for related studies and forensic applications.
Aging/genetics* ; DNA Methylation ; Epigenesis, Genetic ; Epigenomics ; Forensic Genetics/methods* ; Humans ; Semen