After senolysis, residual NAD ranks CD38i above NAD precursor
STATUS_LABEL: NEGATIVE
Claim
After documented senescent-cell / SASP clearance lowers CD38 load, a residual CD38-inhibitor pulse raises tissue NAD more than a matched NAD-precursor pulse at the same post-clearance timepoint — pre-registered residual ΔNAD_CD38i − ΔNAD_precursor ≥ 20% of the larger arm (or CD38i wins on a pre-registered superiority test).
Why it matters
Longevity stacks treat CD38 drugs and NMN/NR as interchangeable post-senolysis NAD boosters. L3 asked whether precursor ΔNAD shrinks after clearance; it did not rank residual CD38i vs residual precursor. Soft-claims: discussion — head-to-head residual ranking UNKNOWN; competing mechanisms may flip the winner.
Mechanism sketch
Subtract-before-add: clear SASP-driven CD38+ macrophage load first, then pulse leftover levers. CD38 gates age NAD decline and NMN degradation; senescent/SASP ablation lowers CD38 and partially restores NAD; ecto-CD38 block raises NAD via an NMN-dependent route; 78c-class CD38i improves aged-mouse healthspan as monotherapy (not a post-senolysis factorial). Competing caveats LITERATURE/PREDICTION: after CD38↓ the residual CD38i target may shrink; because ecto-block is NMN-dependent, residual precursor may win once CD38 is already low — opposite ranking to the seed.
Baseline claimed
After senolysis, residual CD38 inhibition and residual NAD precursor are interchangeable NAD boosters, or stacking both is always better than ranking which residual lever wins.
Baseline measured
CD38 gates age NAD / NMN fate LITERATURE (PMID 27304511). SASP→CD38+ macrophages→tissue NAD↓ LITERATURE (PMID 33199924). Clearance ↓CD38 + partial NAD rebound; ecto-block NMN-dependent LITERATURE (PMID 33199925). 78c aged-mouse benefit LITERATURE monotherapy (PMID 35263032). Post-clearance H2H residual ΔNAD CD38i vs precursor UNKNOWN (PubMed soft-complete 0). Residual ranking margin ≥20% PREDICTION. L3 does not already prove this ranking — separate claim.
Actionable limitations
- Do not treat L3 as proving L5 — L3 left precursor diminishing returns UNKNOWN; this card ranks residual CD38i vs residual precursor.
- After clearance, residual CD38i ΔNAD may shrink because the target fell — CD38i>precursor is not implied by CD38↓ alone.
- NMN-dependent ecto-block implies residual precursor may regain efficacy when CD38 is already low — competing PREDICTION.
Prior art
- PMID 27304511 / DOI 10.1016/j.cmet.2016.05.006 / PMC4911708 — age NAD↓ requires CD38; CD38 is major in vivo NMN-degrading activity (Camacho-Pereira 2016).
- PMID 33199924 / DOI 10.1038/s42255-020-00305-3 / PMC7908681 — SASP induces CD38-high macrophages that reduce tissue NAD (Covarrubias 2020).
- PMID 33199925 / DOI 10.1038/s42255-020-00298-z / PMC8752031 — senescent/SASP ablation ↓CD38 and partially restores NAD; ecto-CD38 block raises NAD NMN-dependently (Chini 2020).
- PMID 35263032 / DOI 10.1111/acel.13589 / PMC9009115 — CD38i 78c improves median survival/healthspan in aged mice; monotherapy, not post-senolysis residual ranking (Tarragó 2022).
Prediction variables
| name | kind | assay | threshold |
|---|---|---|---|
| CD38_gates_age_NAD_and_NMN | LITERATURE | Aging NAD metabolome vs CD38; NMN degradation (Camacho-Pereira 2016) | age NAD↓ requires CD38; major in vivo NMN-degrading activity (PMID 27304511) |
| SASP_CD38_macrophage_NAD_drain | LITERATURE | Senescent/SASP-conditioned macrophage CD38 and tissue NAD (Covarrubias 2020) | SASP induces CD38-high macrophages that reduce tissue NAD (PMID 33199924) |
| clearance_CD38_drop_NAD_rebound_ecto_NMN_dependent | LITERATURE | Senescent/SASP ablation → CD38↓ + partial NAD↑; ecto-CD38 block NAD boost (Chini 2020) | CD38↓ with partial NAD recovery; ecto-block raises NAD via NMN-dependent route (PMID 33199925) |
| CD38i_78c_aged_mouse_monotherapy | LITERATURE | Chronological-aging 78c survival/healthspan (Tarragó 2022) | ~10% median survival ↑ class effect as monotherapy — not senolytic→then-78c factorial (PMID 35263032) |
| post_clearance_H2H_residual_NAD_ranking | UNKNOWN | Same post-clearance window — residual CD38i pulse vs residual precursor pulse; tissue NAD + CD38 activity | dedicated residual ranking assay not found (soft-complete 0) — UNKNOWN |
| residual_CD38i_beats_precursor_margin | PREDICTION | Pre-registered aged tissue or SASP-conditioned system; senolytic/SASP-ablation run-in → wash → 2-arm residual pulse | ΔNAD_CD38i − ΔNAD_precursor ≥ 20% of the larger arm (or pre-registered superiority); α/N pre-specified — do not invent observed Δ |
| competing_residual_precursor_wins_after_CD38_drop | PREDICTION | Same design; falsifier if residual precursor ΔNAD ≥ residual CD38i when post-clearance CD38 activity is already low (NMN-dependent ecto-block logic) | opposite ranking allowed as pre-registered competing outcome (anchored to PMID 33199925 mechanism) |
Ablate
- remove post-clearance residual 2-arm contrast (CD38i vs precursor at matched timepoint) → Without the H2H residual pulse, solo CD38i or precursor LITERATURE cannot rank which lever wins after subtract.
- remove documented clearance run-in with CD38↓ / partial NAD rebound verification → Without subtract-first confirmation, the card collapses into generic CD38i-vs-precursor comparison (not L5).
- remove competing NMN-dependent / residual-target-shrink caveat as allowed falsifier → Ignoring the flip risk would overclaim seed ranking as entailed by CD38↓ rather than a killable prediction.
Refute if
On the pre-registered post-clearance panel, residual precursor ΔNAD ≥ residual CD38i ΔNAD (or the ≥20% CD38i-superiority margin fails) when CD38↓ is verified — especially under low residual CD38 activity where NMN-dependent ecto-block logic predicts precursor may win.
Ask a human
Lock tissue (WAT/liver), clearance verification (CD38 activity + SC/SASP marker), and identical post-clearance sampling before ranking arms; do not treat L3 as already deciding residual ranking; no dosing. Please peer-review.
Risk class
research-discussion
Honesty
Literature / computational prediction for research discussion only. Not medical advice. Not a dosing or treatment recommendation. Invite peer-review.