Species comparison of liver proteomes reveals links to naked mole-rat longevity and human aging

Ivonne Heinze, Martin Bens, Enrico Calzia, Susanne Holtze, Oleksandr Dakhovnik, Arne Sahm, Joanna M. Kirkpatrick, Karol Szafranski, Natalie Romanov, Sai Nagender Sama, Kerstin Holzer, Stephan Singer, Maria Ermolaeva, Matthias Platzer, Thomas Hildebrandt, Alessandro Ori

Mammals display a wide range of variation in their lifespan. Investigating the molecular networks that distinguish long- from short-lived species has proven useful to identify determinants of longevity. Here, we compared the livers of young and old long-lived naked mole-rats (NMRs) and the phylogenetically closely related, shorter-lived, guinea pigs using an integrated omics approach. We found that NMR livers display a unique expression pattern of mitochondrial proteins that results in distinct metabolic features of their mitochondria. For instance, we observed a generally reduced respiration rate associated with lower protein levels of respiratory chain components, particularly complex I, and increased capacity to utilize fatty acids. Interestingly, we show that the same molecular networks are affected during aging in both NMRs and humans, supporting a direct link to the extraordinary longevity of both species. Finally, we identified a novel detoxification pathway linked to longevity and validated it experimentally in the nematode Caenorhabditis elegans. Our work demonstrates the benefits of integrating proteomic and transcriptomic data to perform cross-species comparisons of longevity-associated networks. Using a multispecies approach, we show at the molecular level that livers of NMRs display progressive age-dependent changes that recapitulate typical signatures of aging despite the negligible senescence and extraordinary longevity of these rodents.