ADORA2B/ador-1 is required for multi-system transcriptional adaptation to mild hypoxia and healthspan extension in C....

Mild intermittent hypoxia is emerging as a promising strategy to enhance healthspan, but the molecular mechanisms remain poorly defined. ADORA2B, a hypoxia-inducible adenosine receptor, is known to regulate metabolism and stress responses, yet its role in functional aging is unclear.

Using Caenorhabditis elegans, we investigated the role of the ADORA2B ortholog ador-1 in mediating the healthspan effects of mild hypoxia. We exposed wild-type and ador-1 knockout worms to low-dose cobalt chloride (CoCl₂) and assessed movement, speed, and lifespan metrics through automated imaging. Transcriptomic analyses via 3' RNA-seq and Gene Set Enrichment Analysis (GSEA) were performed to characterize underlying molecular responses.

Mild hypoxia significantly extended healthspan in wild-type C. elegans, increasing sustained locomotor activity and distance traveled throughout adulthood. This benefit was markedly attenuated in ador-1 mutants, which displayed reduced baseline healthspan and a substantially blunted transcriptional response to CoCl₂ treatment. Transcriptomic analyses identified coordinated regulation of canonical hypoxia-responsive genes, including acs-2, icl-1, adh-1, ftn-1 and ftn-2, consistent with activation of hypoxia-responsive transcriptional programs. GSEA revealed activation of pathways related to neuronal plasticity, muscle function and mitochondrial adaptation, together with transcriptional downregulation of ROS-related pathways. In contrast, hypoxia-treated ador-1 mutants exhibited suppression of pathways associated with ciliary function, immune responses, protein synthesis and cellular homeostasis.

ADORA2B is required for the coordinated transcriptional adaptation associated with hypoxia-induced healthspan extension in C. elegans. Loss of ador-1 is associated with impaired baseline healthspan and an attenuated response to hypoxic conditioning. These findings support a model in which successful hypoxic adaptation requires coordinated regulation of multiple biological systems.