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

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

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

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*

OBJECTIVES: To evaluate the forensic application value of an age estimation model based on DNA methylation in eastern Chinese Han population, and to provide a theoretical basis for exploring age estimation models suitable for different detection platforms. METHODS: According to the 6 age-related methylation sites in the published blood DNA methylation age estimation models of Chinese Han population, the DNA methylation level of 48 samples was detected by pyrosequencing and next-generation sequencing (NGS). After submitting DNA methylation levels to the age estimation model, the DNA methylation ages were predicted and compared with their real ages. RESULTS: The 6 DNA methylation sites in both detection techniques were age-related, with an R² of 0.85 and a median absolute deviation (MAD) of 4.81 years when using pyrosequencing；with an R² of 0.84 and MAD of 4.41 years when using NGS. CONCLUSIONS The blood DNA methylation age estimation model can be used under pyrosequencing and multi-purpose regional methylation enrichment sequencing technology based on NGS and it can accurately estimate the age.
Humans ; Aging/genetics* ; CpG Islands ; DNA Methylation ; East Asian People ; Forensic Genetics/methods*

Age estimation based on tissues or body fluids is an important task in forensic science. The changes of DNA methylation status with age have certain rules, which can be used to estimate the age of the individuals. Therefore, it is of great significance to discover specific DNA methylation sites and develop new age estimation models. At present, statistical models for age estimation have been developed based on the rule that DNA methylation status changes with age. The commonly used models include multiple linear regression model, multiple quantile regression model, support vector machine model, artificial neural network model, random forest model, etc. In addition, there are many factors that affect the level of DNA methylation, such as the tissue specificity of methylation. This paper reviews these modeling methods and influencing factors for age estimation based on DNA methylation, with a view to provide reference for the establishment of age estimation models.
Humans ; DNA Methylation ; CpG Islands ; Forensic Genetics ; Neural Networks, Computer ; Linear Models ; Aging/genetics*