Overview
Important classification note: SLU-PP-332 is a synthetic small molecule, not a peptide. It is included in this research library because it circulates in the same research and performance-enhancement communities as many peptides and is frequently discussed alongside them, but chemically it is a small-molecule pan-agonist of the estrogen-related receptors (ERRα, ERRβ and ERRγ) — nuclear receptors that regulate mitochondrial biogenesis and oxidative metabolism gene programmes.
SLU-PP-332 was developed by researchers at Saint Louis University, with the key foundational publication by Billon C et al. in 2023 describing its identification and characterisation as an ERR pan-agonist with "exercise mimetic" properties in mice. The compound has attracted attention for reportedly reproducing some transcriptional and metabolic effects of endurance exercise training in sedentary rodents. All published research to date is confined to mouse studies; there are no published human trials. This guide is for educational and research purposes only. Not medical advice.
Clinical & Research Status
| Evidence Type |
Status |
| Human RCT |
✗ |
| Observational |
✗ |
| Animal Studies |
✔ |
| In Vitro |
✔ |
| Regulatory Approval |
✗ |
Mechanism of Action
SLU-PP-332 acts as a pan-agonist of the three estrogen-related receptor (ERR) isoforms — ERRα, ERRβ and ERRγ. These orphan nuclear receptors are key transcriptional regulators of genes involved in mitochondrial biogenesis, oxidative phosphorylation and fatty acid oxidation, particularly in high-energy-demand tissues such as skeletal muscle, heart and brown adipose tissue. ERR signalling is naturally upregulated during endurance exercise as part of the adaptive response to increased metabolic demand.
By directly activating ERRs pharmacologically, SLU-PP-332 is proposed to switch on the downstream transcriptional programme normally induced by exercise training — including increased mitochondrial density and oxidative enzyme expression — without the animal actually performing exercise. In the founding Billon et al. 2023 study, this was demonstrated through increased expression of genes associated with mitochondrial biogenesis and a shift toward oxidative muscle fibre characteristics in treated mice. This mechanism is mechanistically distinct from AMPK or PPAR-delta pathway activators, though it converges on overlapping downstream outcomes related to endurance capacity.
Research Areas & Reported Effects
Endurance Capacity in Sedentary Mice
The founding research reported that sedentary mice treated with SLU-PP-332 showed significantly improved treadmill running endurance compared to untreated controls, without any exercise training during the study period. This "exercise mimetic" finding is the primary basis for the compound's research interest.
Skeletal Muscle Fibre Type Switching
Published research describes a shift in skeletal muscle fibre composition toward a more oxidative (slow-twitch) phenotype in treated mice, alongside increased mitochondrial content, mirroring adaptations typically associated with endurance training.
Metabolic and Obesity-Related Research
Follow-up preclinical work has examined SLU-PP-332 in diet-induced obesity mouse models, reporting effects on body weight, fat mass and metabolic markers consistent with increased energy expenditure via the ERR-driven oxidative programme.
Research Data Summary
| Study / Model |
Reported Effect |
| Sedentary mouse treadmill endurance study (Billon C et al. 2023) |
Significantly increased running endurance in treated versus untreated sedentary mice, described as an "exercise mimetic" effect. |
| Skeletal muscle gene expression analysis (mouse) |
Upregulation of mitochondrial biogenesis and oxidative metabolism gene programmes. |
| Diet-induced obesity mouse model |
Reported reductions in body weight and fat mass alongside increased energy expenditure markers. |
| In vitro ERR reporter assays |
Demonstrated pan-agonist activity across ERRα, ERRβ and ERRγ isoforms with reported selectivity over other nuclear receptor families. |
Stack Combinations Studied
No peer-reviewed research examines SLU-PP-332 in combination with other compounds or peptides. As a recently characterised research molecule (first published 2023), it has so far been studied only as a standalone agent in mouse models.
⚠️ No verified stack research exists for this compound. This section is intentionally left without fabricated combinations.
Research Protocol Reference
experimental research protocols only — not dosing recommendations. Figures below reflect published mouse study design and have no established human equivalent.
| Protocol |
Dose (experimental model only) |
Duration (experimental model only) |
Frequency (experimental model only) |
Research Context |
| Mouse Endurance/Metabolic Study Protocol |
Reported as intraperitoneal or oral administration in mg/kg ranges in the founding published mouse studies |
Days to several weeks depending on endpoint studied |
Once or twice daily per published protocol |
Endurance capacity testing, muscle fibre analysis, obesity model metabolic studies. |
Observed Side Effects in Research
- No systematic tolerability or side-effect profile has been published for SLU-PP-332 in humans
- Published mouse studies to date have not reported significant adverse findings at doses tested
- No human pharmacokinetic, safety or tolerability data exists in the public literature
As SLU-PP-332 remains an early-stage preclinical research molecule studied only in mice, no human side-effect profile can be stated. This is a data gap, not a safety assurance.
Compound Data
- CAS Number
- Not consistently published in open chemical registries at time of writing
- Molecular Formula
- Not consistently published across available secondary sources; refer to the original Billon et al. 2023 publication for structural data
- Molecular Weight
- Not independently verified across sources
- Half-Life
- Not established in published human pharmacokinetic studies; mouse dosing frequency in published work suggests a relatively short in vivo half-life
- Synonyms
- None widely established; referred to consistently in the literature as SLU-PP-332
- Research Classification
- Synthetic small molecule, pan-agonist of estrogen-related receptors (ERRα/β/γ); not a peptide
Scientific References
Note on evidence base: SLU-PP-332 has a single primary founding publication (Billon et al. 2023) plus a small number of follow-up preclinical studies, all in mice. There are no human trials. This is a legitimate, recently published academic research line, but it is early-stage and should not be conflated with a validated human intervention.
- [Billon C et al. 2023] — Synthetic ERR agonist mimics the metabolic benefits of exercise. — Nature Communications — [Animal / In vitro]
- [Saint Louis University research news, 2023] — Institutional release describing the discovery and exercise-mimetic characterisation of SLU-PP-332 — [Institutional / Secondary source]
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