Hypothesis

Clearing senescent cells before administering anti‑inflammatory agents creates a permissive microenvironment that amplifies the resolution phase of inflammaging. Senolytic removal reduces the burden of SASP‑driven NF‑κB activity, thereby lowering the inflammatory threshold that blunts cytokine‑modulating interventions. When this burden is lifted, omega‑3 fatty acids can more effectively engage GPR120‑STAT3 signaling and promote resolvin biosynthesis, shifting the IL‑6:IL‑10 ratio toward a resolved state.

Mechanistic rationale

• Senolytic clearance diminishes mitochondrial DAMPs and NLRP3 inflammasome priming, decreasing basal NF‑κB signaling (1,3).
• This attenuation renders macrophages more receptive to GPR120‑mediated omega‑3 signaling, enhancing STAT3‑dependent transcription of IL‑10 and resolvin‑producing enzymes (2,6).
• With fewer senescent cells occupying phagocytic capacity, macrophages can better clear apoptotic debris, reinforcing endogenous resolution pathways.

Testable predictions

1. In aged mice, a sequential regimen of dasatinib + quercetin (D+Q) followed by high‑dose omega‑3 will yield a greater reduction in p16^Ink4a+ cells and SASP factors than either monotherapy or the reverse order (4).
2. The IL‑6:IL‑10 ratio will decline more sharply and remain low longer in the sequential group, correlating with increased resolvin D1 and E series levels.
3. Flow cytometry will show a higher proportion of CD206^+ M2‑like macrophages and lower CD86^+ M1‑like cells only after senolytic priming.
4. Vaccine‑specific IgG titers after a sub‑lethal influenza challenge will be preserved in the sequential group, indicating that senolytic priming does not compromise immunological memory when followed by omega‑3.
5. Frailty indices and median lifespan will be improved most in the sequential arm; failure to observe an additive benefit would falsify the hypothesis.

Experimental design

• Use 20‑month‑old C57BL/6 mice (n=15 per group).
• Groups: (1) Vehicle control, (2) D+Q intermittent (1 mg/kg dasatinib + 50 mg/kg quercetin, 2 days weekly), (3) Omega‑3 (EPA/DHA 2 g/kg diet), (4) D+Q → Omega‑3 (senolytic first, 2 weeks then 8 weeks omega‑3), (5) Omega‑3 → D+Q (reverse).
• Endpoints at weeks 0, 4, 8, and 12: flow cytometry for p16^Ink4a+, SASP multiplex (IL‑6, TNF‑α, IL‑10), IL‑6:IL‑10 ratio, resolvin LC‑MS/MS, macrophage markers, hemagglutination inhibition titers, grip strength, gait speed.

If the sequential regimen fails to show superior improvement in the IL‑6:IL‑10 ratio or functional outcomes compared with monotherapies, the hypothesis is falsified.