Mammalian somatic cells and also cells of the yeast Saccharomyces cerevisiae are capable of undergoing a limited number of divisions. Reaching the division limit is referred to, apparently not very fortunately, as replicative aging. A common feature of S. cerevisiae cells and fibroblasts approaching the limit of cell divisions in vitro is attaining giant volumes. In yeast cells this phenomenon ...

Senescent melanocytes accumulate in photoaged skin and are closely related to aging. A better understanding of molecular characteristics senescent might be a key controlling We have developed an vitro model senescence using UV irradiation highlighted that characterized by melanosome transfer dysfunction resulting melanin accumulation. The defective transport was confirmed with ultrastructural c...

Differences between early and late passage cell cultures on the organelle and macromolecular levels have been attributed to cellular "aging". However, concern has been expressed over whether changes in diploid cell populations after serial passage in vitro accurately reflect human cellular aging in vivo. Studies were therefore undertaken to determine if significant differences would be observed...

The RNA binding protein YBX1 is a key regulator of epidermal progenitor cell senescence that prevents the mRNA translation critical senescence-associated secretory phenotypes (SASP) transcripts such as CXCL1 and IL8. Decreased levels during aging enables production SASP-related proteins subsequent induction senescence. Posttranslational modifications YBX1, phosphorylation at Ser 102, can modify...

Increasing evidences indicate that reactive oxygen species are the main factor promoting stem cell aging. Recent studies have demonstrated that coenzyme Q10 (CoQ10) plays a positive role in organ and cellular aging. However, the potential for CoQ10 to protect stem cell aging has not been fully evaluated, and the mechanisms of cell senescence inhibited by CoQ10 are still poorly understood. Our p...

BACKGROUND The purpose of this study was to investigate the aging changes of macromolecular synthesis in animal cells. METHODS We studied 10 groups of mice during development aged from fetal day 19 to postnatal month 24. They were injected with 3H-leucine, a precursor for protein synthesis, sacrificed and the pancreatic tissues were taken out, fixed and processed for light and electron micros...

Zinc as an essential trace element was reported to be involved in regulation of the growth and aging of cells. In this study, rat adipose-derived mesenchymal stem cells were exposed to extremely low frequency electromagnetic field (ELF-EMF) of 50 Hz and 20 mT to evaluate whether exposure to ELF-EMF in the presence of zinc sulfate (ZnSO4) affects the telomerase reverse transcriptase (...

A number of mechanisms have been proposed to explain the phenomenon of frequency aging in the rubidium atomic clock. Helium permeation is one such mechanism. Briefly, the four millitorr of helium in the Earth’s atmosphere can permeate into the resonance cell, changing the clock frequency via the pressure shift of the 0-0 hyperfine transition. On orbit, any He in the resonance cell would permeat...

Declining immune function with age is associated with reduced lymphoid output of hematopoietic stem cells (HSCs). Currently, there is poor understanding of changes with age in the heterogeneous multipotent progenitor (MPP) cell compartment, which is long lived and responsible for dynamically regulating output of mature hematopoietic cells. In this study, we observe an early and progressive loss...

Aging-associated changes in the function of the immune system are referred to as senescent immune remodeling (SIR). Here we review the current understanding on the cellular and molecular mechanisms underlying SIR. We focus on aging-associated changes in T and B cells, and discuss recent evidence supporting the notion that aging of the hematopoietic stem cell (HSC) compartment directly contribut...