CD38i NAD boost shrinks after senolysis
STATUS_LABEL: NEGATIVE
Claim
After documented senescent-cell / SASP clearance lowers CD38 load, residual tissue ΔNAD from a matched CD38-inhibitor pulse is smaller than ΔNAD from the same CD38i without prior clearance at a matched timepoint — pre-registered (ΔNAD_CD38i_alone − ΔNAD_CD38i_post-senolysis) ≥ 20% of ΔNAD_CD38i_alone (or alone wins on a pre-registered superiority test).
Why it matters
Longevity stacks often add CD38i after or with senolytics expecting more NAD. L5/L6 ranked residual CD38i vs precursor on a missing H2H panel and listed symmetric CD38i shrink only as a competing limitation — they did not measure this same-drug ± senolysis factorial. Soft-claims: discussion — CD38i residual shrink after subtract remains UNKNOWN (78c∩named senolytics soft-complete 0).
Mechanism sketch
Subtract-before-add: clear SASP-driven CD38+ macrophage load first, then pulse the same CD38i lever. CD38 gates age NAD decline and NMN degradation; SASP induces CD38-high macrophages that drain tissue NAD; 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 ± senolysis residual factorial). Symmetric diminishing: once CD38 load is subtracted, residual CD38i target shrinks so post-senolysis ΔNAD_CD38i < CD38i-alone ΔNAD — distinct from L5/L6 precursor-vs-CD38i ranking.
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 ± senolysis residual ΔNAD factorial (Tarragó 2022).
Baseline claimed
After senolysis, CD38i still delivers full monotherapy-class ΔNAD (or stacking CD38i with/after senolytics always adds NAD), so same-drug residual shrink need not be tested; L5/L6 already settled it.
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). Same CD38i ± senolysis residual ΔNAD factorial UNKNOWN (78c∩named senolytics soft-complete 0; adjacent hits reviews/OA non-match). Shrink margin ≥20% of alone-arm Δ PREDICTION. L5/L6 do not already prove this — symmetric shrink was limitation only, not a measured claim.
Actionable limitations
- Do not treat L5/L6 as proving L7 — they left residual ranking UNKNOWN and listed symmetric CD38i shrink only as a competing limitation.
- Incomplete clearance: residual CD38+ macrophages can preserve CD38i ΔNAD — shrink is not automatic from “CD38 fell.”
- Baseline NAD rebound after clearance can shrink absolute ΔNAD even if fractional CD38i efficacy holds — assay must pre-register residual vs absolute Δ definition; 78c monotherapy ≠ post-subtract residual.
Method
propose-assay
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 residual factorial (PMID 35263032) |
| same_CD38i_plus_minus_senolysis_residual_NAD_panel | UNKNOWN | Matched timepoint — CD38i alone vs CD38i after senolytic/SASP-ablation run-in; tissue NAD + CD38 activity | dedicated ± senolysis residual CD38i panel not found (78c∩named senolytics soft-complete 0) — UNKNOWN |
| residual_CD38i_shrinks_after_senolysis_margin | PREDICTION | Pre-registered aged tissue or SASP-conditioned system; vehicle vs senolytic/SASP run-in → matched CD38i pulse | (ΔNAD_alone − ΔNAD_post-senolysis) ≥ 20% of ΔNAD_alone (or pre-registered superiority of alone); α/N pre-specified — do not invent observed Δ |
| competing_no_shrink_if_clearance_incomplete_or_absolute_vs_residual | PREDICTION | Same design; falsifier if post-senolysis CD38i ΔNAD ≥ alone-arm when residual CD38 stays high, or shrink is only absolute-baseline artifact | no-shrink / incomplete-clearance / assay-definition failure allowed as pre-registered competing outcomes |
Ablate
- remove ± senolysis run-in factorial with matched CD38i pulse (alone vs post-clearance): Without the same-drug residual contrast, monotherapy 78c LITERATURE cannot show CD38i ΔNAD shrinks after subtract.
- remove documented clearance run-in with CD38↓ / partial NAD rebound verification: Without subtract-first confirmation, the card collapses into generic CD38i dosing comparison (not L7 residual shrink).
- remove L5/L6≠proof + incomplete-clearance + absolute-vs-residual assay discipline: Treating L5/L6 limitations as measured shrink, or ignoring residual CD38+ load / baseline rebound artifacts, would invent a factorial result left UNKNOWN.
Refute if
On the pre-registered ± senolysis panel, residual CD38i ΔNAD after clearance is not smaller than CD38i alone by the ≥20% alone-arm margin (or alone fails superiority) when CD38↓ is verified — especially under incomplete clearance where residual CD38+ load remains high, or when shrink is only an absolute-baseline artifact under the pre-registered residual/fractional definition.
Ask a human
Lock tissue (WAT/liver), clearance verification (CD38 activity + SC/SASP marker), matched CD38i pulse timing, and residual vs absolute ΔNAD definition before claiming shrink; do not treat L5/L6 as proof; no dosing.
Cheap IP
kill_cost_tier=2 · time_to_refute=6w · ip_class=subtract-before-add · vault_hold=no
Execution
execution_status=NOT_RUN · fto_status=UNKNOWN · related_prior=L5/L6 (symmetric shrink was limitation only — not proof)