Hypothesis

Blocking NLRP3 inflammasome activity—or its downstream IL‑6 signaling—will increase experimental pain tolerance and decrease epigenetic age acceleration, as measured by DNAmGrimAge and related clocks.

Rationale

• Chronic pain sensitivity correlates with epigenetic age acceleration (r ≈ -0.5) [1, 2].
• NLRP3 activation in sensory neurons drives mitochondrial ROS, IL‑1β/IL‑18 release, and the transition from acute to chronic pain [4].
• NLRP3 inflammasome activation is a core driver of inflammaging and immunosenescence [3], linking innate immune activation to epigenetic clocks that reflect biological age.

Novel mechanistic insight

We propose that NLRP3‑derived IL‑1β triggers a cascade that suppresses NAD⁺‑dependent SIRT1 activity in peripheral monocytes and sensory neurons. Reduced SIRT1 deacetylates histones and transcription factors, promoting a pro‑aging epigenetic profile (e.g., increased DNAmGrimAge). Simultaneously, mitochondrial ROS from NLRP3 activation sensitizes nociceptors, lowering pain thresholds. Inhibiting NLRP3 (with MCC950) or neutralizing IL‑6 (with tocilizumab) should restore NAD⁺/SIRT1 signaling, dampen ROS production, and thereby improve both pain tolerance and epigenetic age biomarkers.

Testable predictions

1. Pain phenotype – Participants receiving NLRP3 or IL‑6 blockade will show a significant increase in heat and pressure pain thresholds (≥15 % change from baseline) compared with placebo.
2. Epigenetic age – The same intervention will reduce DNAmGrimAge acceleration by at least 1.0 year after 12 weeks of treatment.
3. Mechanistic mediators – Increases in pain tolerance will correlate with (a) decreased NLRP3 inflammasome activity in PBSCs (ASC speck formation), (b) lowered plasma IL‑6 and IL‑1β, and (c) elevated NAD⁺/SIRT1 activity in isolated monocytes.

Experimental design (falsifiable)

• Population: 120 adults aged 45‑65 with elevated baseline pain sensitivity (heat pain threshold <42 °C) and intermediate epigenetic age acceleration (DNAmGrimAge > chronological age by ≥2 years).
• Intervention arms: (1) MCC950 (oral NLRP3 inhibitor), (2) tocilizumab (subcutaneous IL‑6R antagonist), (3) matching placebo. Double‑blind, 12‑week treatment.
• Outcomes: Quantitative sensory testing (heat/pressure pain thresholds) at baseline, week 6, week 12; DNAmGrimAge from blood epigenetics; inflammasome activity (ASC specks via flow cytometry); plasma cytokines; NAD⁺/SIRT1 activity assays.
• Statistical plan: Mixed‑effects models testing group × time interactions; mediation analysis to assess whether changes in inflammasome markers mediate the relationship between treatment and pain/epigenetic outcomes.

Falsifiability

If neither NLRP3 nor IL‑6 blockade produces a statistically significant improvement in pain thresholds and a concurrent reduction in DNAmGrimAge acceleration (or if improvements in pain occur without epigenetic changes, or vice versa), the hypothesis that NLRP3/IL‑6 signaling mechanistically links pain sensitivity to biological age will be falsified. Conversely, concordant improvements across both domains would support the proposed causal pathway.