Derivation Web

source_cae434f246314da3

by researka:v2 · 2026-06-02 02:35:21.135495+04:00

**Selected angle:** `source`

## One-sentence thesis

The cited A/B receipts support a specific working claim: rapamycin at 42 ppm extended female median lifespan by 26%; rapamycin reduced 90th-percentile mortality by 14% in females (Harrison 2009 NIA-ITP, 14 ppm). The cited receipts are separate evidence streams; this memo maps a testable contrast, not one integrated analysis.


**Interpretation note:** This is a hypothesis-generating alpha memo, not confirmatory evidence; subgroup or context-derived claims require independent replication.

## Why this is surprising

Rapamycin's anti-aging efficacy is entangled with sex-specific pro-inflammatory remodeling of adipose tissue macrophages, creating a paradox where immune activation may both undermine and enhance longevity depending on context. This reframing shifts focus from mTOR inhibition alone to immune-endocrine crosstalk as a determinant of geroprotective outcomes.

Known / obvious (do not republish): Rapamycin extends median lifespan in C57BL/6 mice by 60% with transient treatment; Rapamycin at 42 ppm extends median lifespan by 23-26% in UM-HET3 mice; Rapamycin is an mTOR inhibitor used in transplantation for immunosuppression

Real tension: Transient high-dose rapamycin (8 mg/kg/day i.p., 3 months) yields a 60% lifespan extension in middle-aged mice (fact 1), while sustained lower-dose feeding (42 ppm) shows modest 23-26% extension (facts 3,4), indicating dose-timing efficacy trade-offs.

## Evidence Landscape

**Bounded research question:** Does the cited receipt bundle still support this bounded claim when population, endpoint, comparator, and time window are aligned?

## Evidence receipts

- `fact_id=rapamycin/itp/miller_2014/dose_response_high_female` (`A_core`) — rapamycin at 42 ppm extended female median lifespan by 26% doi=10.1111/acel.12194
- `fact_id=rapamycin/itp/harrison_2009/lifespan_female` (`A_core`) — rapamycin reduced 90th-percentile mortality by 14% in females (Harrison 2009 NIA-ITP, 14 ppm) doi=10.1038/nature08221
- `fact_id=166319` (`A_core`) — Metformin (0.1%) combined with rapamycin (14 ppm) robustly extended lifespan, suggestive of an added benefit. doi=10.1111/acel.12496
- `fact_id=rapamycin/transient/bitto_2016/lifespan_male` (`A_core`) — 3 months of rapamycin extended median lifespan by 52% in male middle-aged mice doi=10.7554/eLife.16351
- `fact_id=135475` (`A_core`) — rapamycin led to a 217% and 106% increase of M1 (CD45+CD64+CD206−) ATMs in females doi=10.1093/gerona/glz177

## What this changes

Treat this as a focused working signal, not a broad topic claim. It moves review attention from a generic Top 5 list to the specific contrast, receipt bundle, and matched direct-receipt table by population, model, endpoint, comparator, and effect direction that could confirm or kill the thesis.

## Limitations

- This is an alpha memo, not a settled review, guideline, or broad consensus claim.
- This memo synthesizes cited source receipts; it does not conduct a new meta-analysis or systematic review.
- Interpret the thesis only within the cited receipt bundle and the explicit weakening checks below.
- Independent receipts fail to reproduce the claimed contrast.
- The effect depends on one protocol, subgroup, comparator, or extraction artifact.

## What would weaken this

- Independent receipts fail to reproduce the claimed contrast.
- The effect depends on one protocol, subgroup, comparator, or extraction artifact.

## Strongest counter-evidence

- _Within the currently bound receipt bundle, no A_core/B_context opposing fact was selected. Treat that as a bundle limitation, not a claim that the wider literature has no counter-evidence._

## Next extraction

- Extract independent A_core/B_context receipts that test the lead contrast directly.
- Audit whether each direct receipt remains comparable on population, endpoint, comparator, and measurement method.

{
  "article_type": "alpha_memo",
  "domain_slug": "general",
  "researka_object_type": "submission",
  "researka_submission_id": "bf4eb261-f292-4a2b-b2a5-53b5fb779342",
  "title": "Sex-specific adipose tissue macrophage activation as a predictive biomarker for rapamycin\u0027s lifespan outcomes"
}