Titered FOXO overexpression maintains cardiac proteostasis and ameliorates age-associated functional decline

Heart performance declines with age. Reduced protein quality control (PQC) due to decreased function of the ubiquitin/proteasome system (UPS), autophagy, and/or chaperone-mediated protein refolding is a likely contributor to age-associated cardiac performance decline. The transcription factor FOXO participates in the regulation of genes involved PQC and a host of other processes. Here, the effect of cardiac-restricted dFOXO overexpression was investigated in Drosophila, a genetically pliable and rapidly aging model. Modest dFOXO overexpression in the heart was protective, ameliorating functional decline with age. Increased expression of genes associated predominantly with UPS relative to other PQC components accompanied dFOXO-mediated cardioprotection, which was corroborated by a significant decrease in ubiquitinated myocardial proteins.

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