Modulating the Senescence-Associated Secretory Phenotype (SASP) in Post-Mitotic Neurons Using CRISPRi Targeted to Telomeric Damage Responsive Pathways

Original Research | 2026 | Volume-3 | Issue-2 | Page 78-89

1. Dr. Manoj Kumar, Tutor, Department of Physiology, JHMC, WB.

2. Dr. Shahan Layek, Independent Researcher, West Bengal, India, Email: layekcallmeshahan@gmail.com

Modulating the Senescence-Associated Secretory Phenotype (SASP) in Post-Mitotic Neurons Us.

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Abstract

Background Cellular senescence is increasingly recognized as a key contributor to aging and age-related neurodegenerative disorders. Although post-mitotic neurons do not undergo classical replicative senescence, accumulating evidence suggests that persistent DNA damage, particularly at telomeric regions, can induce a senescence-like phenotype characterized by the activation of the Senescence-Associated Secretory Phenotype (SASP). SASP involves the secretion of pro-inflammatory cytokines, chemokines, growth factors, and proteases that promote neuroinflammation, neuronal dysfunction, and tissue degeneration. Targeting telomeric damage-responsive pathways may offer a novel strategy to suppress SASP and mitigate age-related neuronal decline. Objective: The present study aimed to investigate the efficacy of CRISPR interference (CRISPRi) in modulating SASP expression in post-mitotic neurons by selectively repressing genes involved in telomeric DNA damage response signaling pathways. Methods: Human induced pluripotent stem cell-derived post-mitotic neurons were exposed to oxidative stress and telomere-specific DNA damage to induce a senescence-like state. CRISPRi technology utilizing catalytically inactive dCas9-KRAB was employed to suppress key telomeric damage response regulators, including ATM, ATR, and p21-associated signaling components. Neuronal viability, DNA damage markers, telomere dysfunction-induced foci (TIFs), and expression levels of SASPassociated factors such as IL-6, IL-8, TNF-α, MCP-1, and MMP-3 were evaluated using quantitative PCR, immunocytochemistry, ELISA, and transcriptomic analyses. Results CRISPRi-mediated repression of telomeric damage-responsive genes significantly reduced the expression of multiple SASP factors compared with untreated senescent neurons. Treated neurons exhibited decreased activation of DNA damage signaling pathways, reduced neuroinflammatory cytokine secretion, and lower accumulation of telomere dysfunctioninduced foci. Importantly, neuronal viability and synaptic marker expression were preserved following CRISPRi intervention. Transcriptomic analysis revealed downregulation of inflammatory and senescencerelated pathways without significant disruption of essential neuronal functions. The findings demonstrate that targeted repression of telomeric damage response pathways using CRISPRi effectively attenuates SASP activity in post-mitotic neurons.