SLU-PP-332
An experimental exercise-mimetic small molecule (not a peptide) with rodent-only evidence; no human studies of any kind have been published.
What it is
SLU-PP-332 is an experimental small molecule — not a peptide — that activates estrogen-related receptors (ERRs), the transcription factors behind muscle's endurance programming. It's the newest 'exercise in a pill' candidate, and it exists only in rodent research.
Mice given it showed increased running endurance and fat oxidation without training. There are no human studies of any kind — not even safety — which makes its gray-market availability a pure act of extrapolation.
What researchers have actually studied it for
Endurance and muscle metabolism — in mice and cells only; among the youngest and least human-tested compounds sold anywhere in this market.
How it works
It's a pan-agonist of ERRα/β/γ — nuclear receptors that switch on mitochondrial biogenesis and oxidative-fiber programs in muscle, the machinery endurance training builds. Activating the program chemically is the whole hypothesis.
The molecule itself
A synthetic small molecule (naphthol-derived) — no peptide anywhere in it — functioning as a pan-agonist of estrogen-related receptors (ERRα/β/γ), orphan nuclear receptors that program mitochondrial biogenesis and oxidative muscle fiber type. Nuclear-receptor chemistry: it changes gene transcription, not signaling moments.
Where it came from
Developed in academic medicinal-chemistry work published around 2023 (its name comes from Saint Louis University), SLU-PP-332 drew headlines from rodent endurance findings and jumped to research-chemical catalogs within months — one of the fastest lab-to-gray-market pipelines on record.
The timeline
2010s
ERR biology linked to exercise adaptation in academic work.
2023
Saint Louis University-associated papers report rodent endurance and fat-oxidation gains.
2023–24
Gray-market catalogs list it within months — a record lab-to-vial sprint.
What the research record actually contains
- Rodent studies: increased endurance capacity and fat oxidation.
- Cell-level work on ERR activation and muscle-fiber programming.
- No human data of any kind, including safety.
What could change this assessment
Legitimate academic interest in ERR pharmacology continues; any real program would emerge through characterized derivatives under trials, on a timeline the gray market has already ignored.
What's known about risks
Nothing is known in humans. Nuclear-receptor agonists reshape gene expression broadly — a category where 'no human data' should end the conversation for self-experimenters.
Where it stands legally
No approval anywhere; research-chemical channel only. Given AICAR precedent, tested athletes should assume anti-doping scrutiny of exercise mimetics.
Worth asking a licensed provider
- 1.Am I clear there are zero human studies — safety included?
- 2.What would actual training changes accomplish toward the same goal?
- 3.If I compete, how do exercise mimetics sit with my sport's rules?
Common claims, corrected
“It's the newest exercise peptide.”
Reality: It's not a peptide, and 'exercise' describes mouse treadmill data. Two category errors per five words is efficient even for this market.
“New means advanced.”
Reality: New here means pre-everything: no human safety study exists. Its predecessors in this genre (GW501516) added cancer findings after the hype phase.
SLU-PP-332 FAQ
What is SLU-PP-332?
An experimental small-molecule ERR agonist from academic research — an 'exercise mimetic' with rodent endurance data and zero human studies.
Is SLU-PP-332 a peptide?
No — it's a synthetic small molecule. It's sold through peptide channels because that's where the biohacking market shops.
Is SLU-PP-332 safe?
Unknown at the most basic level — no human safety study exists. It activates nuclear receptors that reshape gene expression, which is not casual territory.
What happened with GW501516, its genre ancestor?
The earlier 'exercise pill' was abandoned after animal cancer findings — and still sells underground. It's the genre's cautionary tale, directly relevant to buying its successors pre-safety-data.
What are estrogen-related receptors?
Nuclear receptors (unrelated to estrogen signaling despite the name) that govern mitochondrial and muscle-fiber gene programs — powerful transcription machinery, which is the argument for caution, not casualness.