Astronauts age 1.9 years in space then reverse it on Earth, while mechanical stimulation rejuvenates old bones

Key Findings

🦴 Mechanical Force Rejuvenates Old Bones by Rewriting DNA

• Senescent bone marrow stem cells showed markedly reduced internal force and impaired mechanical behavior in aged mice

• Moderate mechanical stimulation restored cellular force, increased chromatin accessibility at the FOXO1 gene, and reversed cellular aging in both cell cultures and live mice

• The intervention improved physical performance in aged female mice and showed signs of reducing systemic inflammation

💊 Rapamycin Protects Aging Immune Cells by Fixing DNA Damage

• Human T cells treated with rapamycin showed reduced DNA damage and improved survival after radiation exposure

• In a placebo-controlled study of older adults, low-dose rapamycin significantly reduced p21 (a marker of DNA damage-induced aging) in immune cells

• The protective effects worked by directly reducing DNA damage rather than just slowing protein synthesis or cell division

🎯 Smart Drug Targets Only Old Cells, Spares Healthy Ones

• A new engineered drug system selectively killed senescent retinal cells at 80 μM concentration while having no effect on normal cells even at 200 μM

• The system responds to two hallmarks of aging cells: elevated reactive oxygen species and increased alkaline phosphatase activity

• In age-related macular degeneration models, localized treatment selectively depleted senescent cells without toxicity

🧠 Sleep Loss Impairs Brain Cleanup in Aging Flies

• Aged and sleep-deprived fruit flies showed impaired glial clearance of damaged brain neurons after injury

• Both pharmacological and genetic enhancement of sleep restored the brain's ability to clear damaged neurons in aged flies

• Sleep restored production of Draper, a key protein needed for glial cells to engulf cellular debris

🔋 Yeast Live Longer by Blocking Iron Uptake

• Calorie restriction and overexpression of the Ssd1 protein both extended yeast lifespan by preventing age-related iron accumulation

• Nuclear translocation of the Aft1 iron regulator occurred during aging and predicted remaining lifespan, but was blocked by calorie restriction

• Both interventions were resistant to iron supplementation that normally shortens lifespan, but their benefits were reduced by iron chelation

🫀 Biological Age Beats Chronological Age for Predicting Heart Risk

• In 3,405 atrial fibrillation patients followed for 3 years, biological age calculated from blood chemistry predicted outcomes better than chronological age

• Patients in the highest biological age quartile had 2.11 times higher risk of death, bleeding, stroke, or heart failure compared to the lowest quartile

• The biological age measure showed stronger associations with all major cardiovascular outcomes than simple chronological age