Research Paper Volume 14, Issue 10 pp 4281—4304

Aryl hydrocarbon receptor blocks aging-induced senescence in the liver and fibroblast cells

Ana Nacarino-Palma1,2, , Eva M. Rico-Leo1,2, , Judith Campisi3,4, , Arvind Ramanathan3, , Francisco J. González-Rico1,2, , Claudia M. Rejano-Gordillo1,2, , Ana Ordiales-Talavero1,2, , Jaime M. Merino1,2, , Pedro M. Fernández-Salguero1,2, ,

  • 1 Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz 06071, Spain
  • 2 Instituto Universitario de Investigación Biosanitaria de Extremadura (INUBE), Badajoz 06071, Spain
  • 3 Buck Institute for Research on Aging, Novato, CA 94945, USA
  • 4 Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA

Received: March 9, 2021       Accepted: March 6, 2022       Published: May 26, 2022
How to Cite

Copyright: © 2022 Nacarino-Palma et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Aging impairs organismal homeostasis leading to multiple pathologies. Yet, the mechanisms and molecular intermediates involved are largely unknown. Here, we report that aged aryl hydrocarbon receptor-null mice (AhR−/−) had exacerbated cellular senescence and more liver progenitor cells. Senescence-associated markers β-galactosidase (SA-β-Gal), p16Ink4a and p21Cip1 and genes encoding senescence-associated secretory phenotype (SASP) factors TNF and IL1 were overexpressed in aged AhR−/− livers. Chromatin immunoprecipitation showed that AhR binding to those gene promoters repressed their expression, thus adjusting physiological levels in AhR+/+ livers. MCP-2, MMP12 and FGF secreted by senescent cells were overproduced in aged AhR-null livers. Supporting the relationship between senescence and stemness, liver progenitor cells were overrepresented in AhR−/− mice, probably contributing to increased hepatocarcinoma burden. These AhR roles are not liver-specific since adult and embryonic AhR-null fibroblasts underwent senescence in culture, overexpressing SA-β-Gal, p16Ink4a and p21Cip1. Notably, depletion of senescent cells with the senolytic agent navitoclax restored expression of senescent markers in AhR−/− fibroblasts, whereas senescence induction by palbociclib induced an AhR-null-like phenotype in AhR+/+ fibroblasts. AhR levels were downregulated by senescence in mouse lungs but restored upon depletion of p16Ink4a-expressing senescent cells. Thus, AhR restricts age-induced senescence associated to a differentiated phenotype eventually inducing resistance to liver tumorigenesis.


AhR: Aryl Hydrocarbon Receptor; C12FDG: 5-Dodecanoylaminofluorescein Di-β-D-Galactopyranoside; FICZ: 6-formyl-indolo (3,2-b) carbazole); HGF: Hepatocyte growth factor; SASP: Senescence-associated secretory phenotype; TMRM: Tetramethylrhodamine; TTF: Tail tip fibroblast; VEGF: Vascular-endothelial growth factor.