Alterations in Chromatin Functions during Aging in Vitro
Changes in the metabolism of the human diploid cell line WI-38 during the aging process have been extensively characterized. For example, studies have shown age-associated increases in glycogen content (1), lipid synthesis (2), lipid content (3), the number of lysosomes (4,5) and the specific activities of lysosomal enzymes (6–8). In addition, age related decreases in the specific activities of transketolase and 6-phosphogluconate dehydrogenase have also been reported (9). If these age-related changes represent the phenotype of fundamental changes in the expression of the cellular genome, then alterations in chromatin functions could underlie the modulation of the aging process. In this regard, the metabolic alterations mentioned earlier may only reflect functional changes as they occur within the cellular chromatin. However, few reports have been published on age-associated alterations in chromatin functions.
KeywordsHistone Acetylation Histone Protein Young Cell Human Diploid Cell Template Activity
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