Sullivan DI, Bello FM, Silva AG, Redding KM, Giordano L, Hinchie AM, Loughridge KE, Mora AL, Königshoff M, Kaufman BA, Jurczak MJ, Alder JK. Intact mitochondrial function in the setting of telomere-induced senescence.
Aging Cell 2023;
22:e13941. [PMID:
37688329 PMCID:
PMC10577573 DOI:
10.1111/acel.13941]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/25/2023] [Accepted: 07/07/2023] [Indexed: 09/10/2023] Open
Abstract
Mitochondria play essential roles in metabolic support and signaling within all cells. Congenital and acquired defects in mitochondria are responsible for several pathologies, including premature entrance to cellar senescence. Conversely, we examined the consequences of dysfunctional telomere-driven cellular senescence on mitochondrial biogenesis and function. We drove senescence in vitro and in vivo by deleting the telomere-binding protein TRF2 in fibroblasts and hepatocytes, respectively. Deletion of TRF2 led to a robust DNA damage response, global changes in transcription, and induction of cellular senescence. In vitro, senescent cells had significant increases in mitochondrial respiratory capacity driven by increased cellular and mitochondrial volume. Hepatocytes with dysfunctional telomeres maintained their mitochondrial respiratory capacity in vivo, whether measured in intact cells or purified mitochondria. Induction of senescence led to the upregulation of overlapping and distinct genes in fibroblasts and hepatocytes, but transcripts related to mitochondria were preserved. Our results support that mitochondrial function and activity are preserved in telomere dysfunction-induced senescence, which may facilitate continued cellular functions.
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