Comparative phenotyping of C57BL/6J substrains reveals distinctive patterns of cardiac aging

• DOI: 10.1007/s11357-025-01543-7
• Publication Date: 2025-01-30T20:38:32Z
• Authors: Sophia Walter; Patricia Baumgarten; Niklas Hegemann; Steffen P. Häseli; Stefanie Deubel; Julia Jelleschitz; Annika Höhn; Nikolaus Berndt; Wolfgang M. Kuebler; Jana Grune; Christiane Ott
• Keywords: Cardiac Fibrosis

Abstract Research in aging often refers to animal models, particularly C57BL/6J (B6J) mice, considered gold standard. However, B6J mice are distributed by different suppliers, which results divers substrains exhibiting notable phenotypic differences. To ensure a suitable phenotype of cardiac aging, we performed heart analyses young (5 months) and old (24 from two substrains: B6JRj (Janvier) B6JCrl (Charles River). In hearts both substrains, myocardial fibrosis increased with age; however, only hypertrophy associated decreased ejection fraction was observed. Gene set enrichment analysis tissue using proteomic data revealed age-associated pathway changes between the especially oxidative phosphorylation. Functional assessment isolated cardiomyocytes verified impairment during mice. Overall, demonstrate that manifests as moderate systolic dysfunction while display no functional age.