fig1

Figure 1. Cardiac aging alters mitochondrial biogenesis. (A) Schematic representation of the study comparing young (10-month) vs. old (25-month) CBA/CaJ mice hearts subjected to genomic DNA, mRNA, and protein isolation and investigation of mt biogenesis, mt and ER stress response, autophagy, and metabolic alterations. This schematic figure was created using BioRender (www.app.biorender.com). (B) Relative mRNA expression levels of mtDNA-encoded (Nd1, Nd4, mt-Cytb, mt-Co2, mt-Atp6) and nDNA-encoded mitochondrial Ndufs4. (C) Relative mtDNA content (top) normalized to Tert, and mRNA expression levels of Tfam normalized to Gapdh in young vs. old hearts. Experiments were conducted in triplicate, and relative expression levels were plotted. Values are presented as mean ± SEM (n = 3-10). *P < 0.05, **P < 0.01, by an unpaired Student’s t-test, using GraphPad Prism software.