Hypothesis

Administering senolytic drugs during the fasting window enhances clearance of senescent cells and reduces SASP‑mediated inflammation by leveraging fasting‑activated AMPK‑SIRT1 signaling, which suppresses NF‑κB‑driven SASP transcription and increases lysosomal drug uptake.

Mechanistic Rationale

• Fasting activates AMPK and raises NAD+, leading to SIRT1 activation 4. SIRT1 deacetylates the NF‑κB p65 subunit, diminishing transcription of IL‑6, IL‑8, and other SASP factors.
• AMPK activation also promotes autophagosome formation and lysosomal biogenesis, potentially increasing intracellular accumulation of senolytics such as dasatinib and quercetin, which are known to act via lysosomal pathways.
• Transient SASP release upon senolytic‑induced cell death is therefore blunted, lowering the risk of inflammation‑driven tissue damage.

Testable Predictions

1. Senolytic dosing in the fasted state will produce a greater reduction in circulating SASP biomarkers (e.g., GDF‑15, IL‑6) compared with dosing in the fed state.
2. The fasted‑state senolytic group will show higher autophagic flux markers (LC3‑II/I ratio, p62 degradation) in peripheral blood mononuclear cells.
3. Physical function improvements (e.g., gait speed, grip strength) will be larger after a 12‑week regimen of intermittent fasting plus fasted‑timed senolytics versus fasting plus fed‑timed senolytics.

Experimental Design

• Recruit 120 older adults (aged 70‑85) with frailty indicators.
• Randomize to four arms (n=30 each): (a) TRE 14/10 + placebo, (b) TRE 14/10 + senolytic (D+Q) taken at the start of the fasting window, (c) TRE 14/10 + senolytic taken 2 h after meal (fed), (d) control diet + placebo.
• Intervention duration: 12 weeks, senolytic given twice weekly (standard dosing).
• Primary outcomes: change in plasma SASP panel, autophagic flux in PBMCs, Short Physical Performance Battery score.
• Secondary outcomes: adverse events, cytokine storm markers (CRP, IL‑1β).

Potential Outcomes and Falsification

• If the fasted‑senolytic arm shows significantly greater SASP reduction and functional gain than the fed‑senolytic arm (p<0.05), the hypothesis is supported.
• No difference between fasted and fed senolytic arms, or a worsening of inflammatory markers in the fasted arm, would falsify the proposed mechanistic advantage.