Siglec receptors impact mammalian lifespan by modulating oxidative stress

Schwarz F, Pearce OM, Wang X, Samraj AN, Läubli H, Garcia JO, Lin H, Fu X, Garcia-Bingman A, Secrest P, Romanoski CE, Heyser C, Glass CK, Hazen SL, Varki N, Varki A, Gagneux P. Siglec receptors impact mammalian lifespan by modulating oxidative stress. Elife. 2015 Apr 7;4. doi: 10.7554/eLife.06184. PMID: 25846707 PMCID: PMC4384638 

Abstract
Aging is a multifactorial process that includes the lifelong accumulation of molecular damage, leading to age-related frailty, disability and disease, and eventually death. In this study, we report evidence of a significant correlation between the number of genes encoding the immunomodulatory CD33-related sialic acid-binding immunoglobulin-like receptors (CD33rSiglecs) and maximum lifespan in mammals. In keeping with this, we show that mice lacking Siglec-E, the main member of the CD33rSiglec family, exhibit reduced survival. Removal of Siglec-E causes the development of exaggerated signs of aging at the molecular, structural, and cognitive level. We found that accelerated aging was related both to an unbalanced ROS metabolism, and to a secondary impairment in detoxification of reactive molecules, ultimately leading to increased damage to cellular DNA, proteins, and lipids. Taken together, our data suggest that CD33rSiglecs co-evolved in mammals to achieve a better management of oxidative stress during inflammation, which in turn reduces molecular damage and extends lifespan.

KEYWORDS: Siglec; aging; evolutionary biology; genomics; immunology; inflammation; mouse; reactive oxygen species