What this means
Researchers exposed heart cells to radiation and gave some of them SS-31. SS-31 reduced several aging signs, but this was only tested in cells, not people.
Plain-English summary written by an AI model from the abstract. The original is below.
- Who it was tested in
- Heart muscle cells (H9C2) and human stem-cell-derived heart cells in a lab dish
- Kind of research
- A study
The science
- Original title
- Mitochondrial-targeted SS-31 peptide attenuates radiation-induced cardiomyocyte senescence.
- Authors
- Xie L, Wu J, Fan J et al.
- Journal
- Journal of radiation research
- Published
- Jul 15, 2026
- Study type
- Study · in humans
- PMID
- 42456009 ↗
Abstract
Exposure to ionizing radiation, such as from radiation therapy or accidental radiation exposure can have adverse effects on the heart. While radiation injury in the heart may include cardiomyocyte senescence, there are no available strategies to prevent this phenomenon. This study evaluated the effects of the mitochondrial-targeted peptide SS-31 (elamipretide) on radiation-induced cell senescence in cardiomyoblast H9C2 cells and human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs). Exposure to γ-radiation at doses of 2, 5, and 10 Gy inhibited H9C2 cell proliferation in a dose-dependent manner, and induced senescence-associated beta-galactosidase (SA-β-gal) staining, a gold standard of cell senescence. Treatment with SS-31 (1 μM) for 7 days reduced SA-β-gal positive staining from 67% to 38% in H9C2 cells under 10 Gy radiation. SS-31 also prevented increases in the expression of p16 and p21, two well-accepted senescence markers, in irradiated H9C2 cells and hiPSC-CMs. SS-31 decreased the canonical senescence-associated secretory phenotype markers TNF-α, IL-6, and IL-1β. SS-31 also reversed the BAX/bcl-2 ratio, a marker of mitochondrial-related apoptosis. Moreover, SS-31 mitigated mitochondrial production of reactive oxygen species. Interestingly, we found that a dose of 10 Gy increased mitochondrial respiration, and SS-31 reversed this elevation. This study suggests that SS-31 is a promising compound that may prevent radiation-induced cardiomyocyte senescence.
Xie L, Wu J, Fan J et al. Mitochondrial-targeted SS-31 peptide attenuates radiation-induced cardiomyocyte senescence. Journal of radiation research. 2026. doi:10.1093/jrr/rrag048. PMID: 42456009. https://pubmed.ncbi.nlm.nih.gov/42456009/
Related research
The Role of Oxidative Stress in Heart Failure: Mechanisms and Therapeutic Targets.
Heart failure is characterised by increased production of reactive oxygen species (ROS), which contribute to apoptotic signalling.
A peptide eased signs of aging in heart cells damaged by a cancer drug
Researchers treated heart muscle cells in a dish with a cancer drug, then a peptide called SS-31. The peptide reduced several signs of aging, but not cell cycle arrest. This was done only in lab cells, so it does not show the peptide would help people.
Two drugs together eased stroke brain damage in mice
Researchers gave mice two compounds, alone and together, after a stroke-like injury to the brain. The mice given both had less brain damage and better nerve function than those given either one alone.
Targeting Mitochondria for Postoperative Cognitive Dysfunction: From Mechanisms to Therapeutics.
Postoperative cognitive dysfunction (POCD) is a frequent neurological complication in older surgical patients, leading to substantial declines in quality of life and placing a considerable burden on society.
Two mitochondria-targeted drugs studied in aged female mice with fatty liver disease
Researchers gave two drugs to older mice with fatty liver disease caused by a rich diet. Both drugs improved liver markers in the mice, but this does not show they would help people.
The Oxidative-Mitochondrial-Inflammatory Axis in Retinitis Pigmentosa: Extracellular mtDNA as Biomarker and Therapeutic Read-Out.
Retinitis pigmentosa (RP) is the most common inherited retinal dystrophy (prevalence ~1:4000) and a leading Mendelian cause of working-age blindness.
See all research on Elamipretide (SS-31) →