Skeletal muscle RBM3 expression is associated with extended lifespan in Ames Dwarf and calorie restricted mice.

Abstract

RNA binding protein motif 3 (RBM3) is an RNA-binding and cold shock protein that protects myoblasts and promotes skeletal muscle hypertrophy by enhancing mRNA stability and translation. Muscle size is decreased during aging; however, it is typically delayed in models of extended lifespan such as the long-lived Ames Dwarf (df/df) mice and calorie restricted (CR) animals compared to age-matched controls. In light of the protective and anabolic effects of RBM3 in muscle, we hypothesized that RBM3 expression is higher in long-lived animal models. Young and old df/df mice, and adult and old UM-HET3 CR mice were used to test this hypothesis. Gastrocnemius muscles were harvested and protein was isolated for RBM3 protein measurements. CR induced a 1.7 and 1.3-fold elevation in RBM3 protein abundance compared to adult and old male mice fed ad libitum (AL) diets, respectively; this effect was shared between males and females. Ames dwarfism induced a 4.6 and 2.7-fold elevation in RBM3 protein abundance in young and old df/df mice compared to normal control littermates, respectively. In contrast, there was an age-associated decrease in cold-inducible RNA-binding protein (CIRP), suggesting these effects are specific for RBM3. Lastly, there was an age-associated increase in RNA degradation marker decapping enzyme 2 (DCP2) in UM-HET3 mice that was mitigated by CR. These results show that muscle RBM3 expression is correlated with extended lifespan in both df/df and CR animals. Identifying how RBM3 exerts protective effects in muscle may yield new insights into healthy aging of skeletal muscle.

• Authors: Zachary R Hettinger, Amy L Confides, Peter W Vanderklish, Silvana Sidhom, Michal M Masternak, Esther E Dupont-Versteegden
• Journal: Experimental gerontology (Exp Gerontol) Vol. 146 Pg. 111214 (04 2021) ISSN: 1873-6815 [Electronic] England
• PMID: 33385482 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2020 Elsevier Inc. All rights reserved.

Chemical References

• RNA-Binding Proteins
• Rbm3 protein, mouse

Topics

• Aging
• Animals
• Caloric Restriction
• Dwarfism
• Female
• Longevity
• Male
• Mice
• Muscle, Skeletal
• RNA-Binding Proteins (genetics)