Hypothesis

Early pharmacological inhibition of the NLRP3 inflammasome will rapidly increase pressure pain threshold in middle‑aged adults showing early inflammaging signatures, and this improvement will precede measurable reversal of CD8+ T‑cell exhaustion and epigenetic age acceleration.

Mechanistic Rationale

NLRP3 activation in peripheral sensory neurons releases IL‑1β that phosphorylates Nav1.8 channels, lowering the activation threshold for action potentials and thus reducing pain tolerance [https://doi.org/10.1016/j.cmet.2013.09.010]. The same IL‑1β, through NF‑κB signaling, fuels systemic sterile inflammation that drives CD8+ T‑cell exhaustion (PD‑1+, TIM‑3+) and accelerates epigenetic clocks such as GrimAge [https://doi.org/10.1073/pnas.1810692116] [https://www.iasp-pain.org/publications/pain-research-forum/papers-of-the-week/paper/122107-express-epigenetic-aging-associated-clinical-and-experimental-pain-community-dwelling/]. Because neuronal NLRP3 activity mirrors the inflammasome activity in myeloid cells, a change in pain threshold serves as a proximal readout of the inflammasome’s systemic tone.

Experimental Design

• Population: 120 participants aged 45‑60 with plasma CXCL9 > 90th percentile but CD8+ counts within normal range.
• Intervention: Double‑blind, placebo‑controlled, 4‑week course of MCC950 (NLRP3 inhibitor) 10 mg PO daily.
• Baseline & Follow‑up: Pressure pain threshold (algometer, knee), plasma cytokines (IL‑6, TNF‑α, IL‑1β), flow cytometry for CD8+ PD‑1/TIM‑3, GrimAge epigenetic clock.
• Primary outcome: Change in pain threshold from baseline to week 4.
• Secondary outcomes: Change in GrimAge delta, CD8+ exhaustion frequency, cytokine levels.

Expected Outcomes and Falsifiability

If the hypothesis holds, the MCC950 group will show a ≥15 % increase in pain threshold concurrent with a significant reduction in GrimAge acceleration (≥0.5 years) and a decrease in exhausted CD8+ fraction (≥10 %). Failure to observe pain threshold improvement despite adequate drug exposure, or observing pain threshold improvement without corresponding immunological/epigenetic changes, would falsify the proposed mechanistic link.

Potential Implications

A simple, bedside pain‑threshold test could serve as a functional biomarker to guide NLRP3‑targeted therapies in the window before irreversible immunosenescence, offering a low‑cost alternative to multi‑omics aging clocks.