Hallmarks of Aging: Difference between revisions

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| style="text-align:center; background-color:hsla(180, 100%, 85%);" |[[File:Telomeres transparent.png|frameless|88x88px]]
| style="text-align:center; background-color:hsla(180, 100%, 85%);" |[[File:Telomeres transparent.png|frameless|88x88px]]
| style="background-color:hsla(180, 100%, 85%);" |'''Telomere attrition'''
| style="background-color:hsla(180, 100%, 85%);" |'''Telomere attrition'''
| style="background-color:hsla(180, 100%, 85%);" |
| style="background-color:hsla(180, 100%, 85%);" |Telomere attrition refers to the progressive shortening of telomeres, which are protective sequences at the ends of chromosomes. This occurs due to the inability of DNA polymerases to completely replicate the ends of linear DNA, and the absence of telomerase in most somatic cells. Shortened telomeres lead to cellular aging and reduced regenerative capacity, manifesting as replicative senescence or Hayflick limit{{pmid|17024208}}. Shelterins protect telomeres but may mask damage leading to persistent DNA damage and cellular stress{{pmid|18680434}}. Dysfunctions in telomere maintenance are linked to various age-related diseases{{pmid|22965356}}.
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|Telomere shortening is observed during normal aging in humans and mice{{pmid|17876321}}.
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|Excessive telomere attrition due to stress or genetic factors accelerates cellular aging and the onset of age-related pathologies{{pmid|22426077}}.
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|Maintaining telomere length through telomerase activation or shelterin integrity can delay aging and extend lifespan, as shown in mouse models and suggested by human epidemiological studies{{pmid|21113150}}; {{pmid|22585399}}.
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|Telomere shortening is associated with a variety of human diseases, including pulmonary fibrosis, dyskeratosis congenita, and aplastic anemia, often linked to deficiencies in telomerase or shelterin components{{pmid|22965356}}.
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| style="text-align:center; background-color:hsla(180, 100%, 85%);" |[[File:Epigenome-transparent-upscale.png|frameless|85x85px]]
| style="text-align:center; background-color:hsla(180, 100%, 85%);" |[[File:Epigenome-transparent-upscale.png|frameless|85x85px]]
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==History==
==History==