Study summary · research use only
SS-31 and NMN: Two paths to improve metabolism and function in aged hearts
Plain-language summary
Paraphrased from the published abstract below — not a verdict on whether anything works.
In this mouse study, researchers tested mitochondrial-targeted compounds SS-31 and NMN, alone and combined, on hearts from old mice, assessing function by echocardiography. SS-31 partially reversed an age-related decline in diastolic function, while NMN reversed an age-related deficiency in systolic function at higher workload. Metabolomic analysis showed NMN and combined treatment increased nicotinamide and 1-methylnicotinamide, indicating greater NAD+ turnover, though only combined treatment gave significantly higher steady-state NAD(H). Using magnetic resonance spectroscopy across cardiac workloads, the PCr/ATP ratio decreased with workload in old control but not young hearts, and both drugs normalized this response. SS-31 and NMN were also linked to increased mitochondrial NAD(P)H under higher workload, while only NMN increased NAD+ with work; combined treatment restored different aspects of mitochondrial and heart function in old hearts.
Abstract
The effects of two different mitochondrial-targeted drugs, SS-31 and NMN, were tested on Old mouse hearts. After treatment with the drugs, individually or Combined, heart function was examined by echocardiography. SS-31 partially reversed an age-related decline in diastolic function while NMN fully reversed an age-related deficiency in systolic function at a higher workload. Metabolomic analysis revealed that both NMN and the Combined treatment increased nicotinamide and 1-methylnicotinamide levels, indicating greater NAD+ turnover, but only the Combined treatment resulted in significantly greater steady-state NAD(H) levels. A novel magnetic resonance spectroscopy approach was used to assess how metabolite levels responded to changing cardiac workload. PCr/ATP decreased in response to increased workload in Old Control, but not Young, hearts, indicating an age-related decline in energetic capacity. Both drugs were able to normalize the PCr/ATP dynamics. SS-31 and NMN treatment also increased mitochondrial NAD(P)H production under the higher workload, while only NMN increased NAD+ in response to increased work. These measures did not shift in hearts given the Combined treatment, which may be owed to the enhanced NAD(H) levels in the resting state after this treatment. Overall, these results indicate that both drugs are effective at restoring different aspects of mitochondrial and heart health and that combining them results in a synergistic effect that rejuvenates Old hearts and best recapitulates the Young state.
pepmg summarizes the peer-reviewed literature and links to every source — it sells nothing, ships nothing, and gives no medical, dosing, or human-use guidance. Don't just trust this summary: follow the citation to its source and read it yourself. Research use only.