Rapamycin makes exercise work against you

Rapamycin and Exercise: A Landmark Negative Result

• The RAPA-EX-01 trial — a 13-week double-blind RCT in 40 sedentary adults aged 65–85, VitaDAO-co-funded — found weekly 6 mg rapamycin blunted every exercise adaptation: placebo outperformed rapamycin on chair stands, 6-minute walk, and grip strength, with sensitivity analyses showing statistically significant declines of 2.46–3.44 reps. Rapamycin users also showed elevated inflammation markers; the likely mechanism is mTOR inhibition suppressing anabolic signaling that makes resistance training effective.
• A $38M VITAL-H trial is now enrolling 700+ adults in their 60s to test rapamycin, dapagliflozin, and semaglutide in combination, using "intrinsic capacity" — combined physical and cognitive function — as a proposed FDA healthspan endpoint. The multi-drug rationale: convergent effects on mTOR, AMPK, and glucose metabolism.

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Senolytics: A Brain Safety Signal and a New Ferroptosis Mechanism

• A PNAS study found that dasatinib + quercetin causes demyelination in the mouse corpus callosum via endoplasmic reticulum stress in oligodendrocytes — producing MS-like lesion patterns within 20 minutes of treatment onset, the first documentation of D+Q effects on a healthy brain. Cells remained viable, suggesting reversibility, but this is a new safety signal independent of the spinal disc efficacy data reported last issue.
• Researchers at Imperial College London and MRC identified a new senolytic class targeting GPX4, published in Nature Cell Biology: senescent cells upregulate GPX4 to evade ferroptosis (iron-dependent cell death), and chloroacetamide compounds that inhibit GPX4 selectively trigger ferroptosis in senescent cells while sparing healthy ones. Combined with chemotherapy, the compounds cleared persistent senescent tumor cells in melanoma, prostate, and ovarian cancer models.

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Brain Aging, Blood Biology, and a New Dynamic Biomarker

• Texas A&M researchers developed a two-dose nasal spray that reversed brain aging in mice, published in Journal of Extracellular Vesicles: EVs carrying microRNAs bypass the blood-brain barrier, suppress NLRP3 inflammasome and cGAS-STING pathways, and restore mitochondrial function in brain cells. Two doses produced lasting improvements in object recognition and spatial memory in both male and female subjects; a US patent is filed, no human data yet.
• A Nature review synthesizing plasma proteomics, metabolomics, and single-cell immunomics positions blood as a central regulatory axis of aging: proteomic clocks from circulating proteins predict organ-specific disease trajectories, young plasma transfer induces epigenetic rejuvenation across multiple tissues, and therapeutic plasma exchange shows translational potential for neurodegenerative disease.
• A Nature Communications study of 2,276 cancer patients found facial aging rate (FAR) — AI-derived speed of biological aging across serial clinical photographs — independently predicts overall survival at 10–365, 366–730, and 731–1,460 day intervals, controlling for age, sex, race, and diagnosis. As a dynamic, photography-based measure, FAR sidesteps the intraday methylation clock instability documented by Yale in this newsletter's first issue.

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ARDD Consensus, AI Drug Screening, Inflammaging Funding, and Peptides

• The 12th Aging Research and Drug Discovery meeting at Copenhagen produced a consensus report in Aging-US backing a "disease-first" regulatory strategy — targeting age-related diseases to validate underlying aging biology interventions — consistent with the FDA approach accepted for Life Biosciences' ER-100 trial. Field-wide themes include organ imaging clocks outperforming methylation approaches and AI-designed proteins accelerating drug discovery; several Altos Labs scientists contributed.
• Sinclair's lab has screened ~8 billion virtual compounds using AI to find a small molecule replicating OSK reprogramming, as described in an April 16 interview: a model trained on millions of human cells evaluates candidates; equivalent manual work estimated at 160 years. Goal: replace gene therapy (~$100K/patient) with an oral pill. Still in cell-stage screening.
• Belgian biotech Coultreon raised $125M targeting SIK3 kinase to shift inflammatory disease treatment toward proactive systemic control rather than blunt immunosuppression — a mechanism directly applicable to inflammaging as a longevity driver.
• A Sports Medicine systematic review of 10 popular peptides — BPC-157, TB-500, CJC-1295, GHK-Cu, MOTS-c, and others — found no strong human evidence for any compound: BPC-157 has one unconvincing retrospective human survey; a CJC-1295 trial was halted after a patient death; MOTS-c has zero human data. The review adds independent weight to evidence gap concerns as FDA prepares to ease compounding access ahead of its July advisory panel.