Exercise Mimetic · Preclinical Only

SLU-PP-332 & SLU-PP-915: Exercise in a Pill?

📄 8 PubMed citations

Synthetic pan-ERR agonists that switch on an aerobic-workout gene program in mice. They’re trending on X as a shortcut to single-digit body fat — but every result so far comes from animals and cell cultures, not people.

🔬 Unlike the hype threads, this page separates what SLU-PP-332/915 actually did in mice from what’s been shown in humans (nothing yet), and explains how these ERR agonists differ from GLP-1 drugs like tirzepatide, PPARδ compounds like Cardarine, and the mitochondrial peptide MOTS-c.
0
Human clinical trials — all data is preclinical
3
ERR receptor subtypes activated (α, β, γ)
2
Lead compounds: SLU-PP-332 & SLU-PP-915

How It Works

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Exercise-mimetic gene program

In mice, SLU-PP-332 switches on an ERRα-dependent acute aerobic-exercise genetic program — the same transcriptional response triggered by a bout of endurance training. SLU-PP-915 induces the exercise-marker gene Ddit4 to levels matching or exceeding treadmill running.

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Metabolic reprogramming

Activating ERRα/β/γ drives mitochondrial biogenesis, oxidative phosphorylation and fatty-acid oxidation. In obese mice, SLU-PP-332 raised energy expenditure and fat-burning, reduced fat-mass accumulation, and improved insulin sensitivity.

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Muscle & endurance

SLU-PP-332 increased type IIa oxidative muscle fibers and enhanced running endurance in mice. SLU-PP-915 improved aerobic distance and duration and synergized with actual exercise training rather than replacing it.

⚖️
332 vs 915: the key difference

SLU-PP-332 is not orally bioavailable and has a short half-life — in studies it was injected. SLU-PP-915 is a chemically distinct successor built to be orally active in mice. Neither has been dosed in humans.

What the Data Shows

Mouse exercise-capacity studies
endurance, type IIa fibers, Ddit4
Multiple
Mouse metabolic / fat-mass studies
diet-induced-obese & ob/ob models
Yes
Human-cell (ex vivo) pilot
myoblasts from inactive women
1 pilot
Human clinical trials
safety & efficacy in living people
0

Key Takeaways

✅ What We Know
  • SLU-PP-332 and SLU-PP-915 are synthetic pan-ERR (α/β/γ) agonists developed by the Burris lab as "exercise mimetics."
  • In mice, SLU-PP-332 turns on an ERRα-driven acute aerobic-exercise gene program and raises mitochondrial function, fatty-acid oxidation and energy expenditure.
  • In diet-induced-obese and ob/ob mice, SLU-PP-332 reduced fat-mass accumulation and improved insulin sensitivity — without the animals exercising.
  • SLU-PP-915 is a chemically distinct, orally bioavailable successor; SLU-PP-332 itself is not orally bioavailable and has a short half-life.
  • Anti-doping labs are already characterizing both compounds as potential performance-enhancing drugs.
⚠️ What We Don't Know
  • Whether any of this works in humans — there are zero human clinical trials, so human dose, safety and real-world fat loss are unknown.
  • The "year-round single-digit body fat" framing on X is an extrapolation from mouse fat-mass data, never demonstrated in a person.
  • Long-term safety — ERRα also fuels tumor metabolism, a theoretical risk no human study has addressed.
  • What is actually in vendor "research-chemical" caps — identity, purity and dose are unverified and these compounds are unapproved.
  • They are not GLP-1 drugs (tirzepatide/semaglutide) and not the peptide MOTS-c — the nuclear-receptor mechanism is entirely different.

Frequently Asked Questions

What are SLU-PP-332 and SLU-PP-915?

They are synthetic small molecules that activate all three estrogen-related receptors (ERRα, β and γ). Developed by Thomas Burris’ lab, they are called "exercise mimetics" because in mice they reproduce much of the gene-expression and metabolic response to aerobic exercise. SLU-PP-332 came first; SLU-PP-915 is a newer, orally bioavailable version.

Do SLU-PP-332 and SLU-PP-915 actually cause fat loss?

In mice, yes — SLU-PP-332 increased energy expenditure and fatty-acid oxidation and reduced fat-mass accumulation in obese mice without exercise. But there is no human data. The viral claim of "single-digit body fat" in people is an extrapolation from rodent studies, not a demonstrated human result.

Are SLU-PP-332 and SLU-PP-915 the same as a GLP-1 like tirzepatide or semaglutide?

No. GLP-1 drugs cause weight loss mainly by reducing appetite and food intake through gut/brain signaling. ERR agonists work on nuclear receptors inside muscle and other tissues to mimic the metabolic effects of exercise. Different target, different mechanism — and unlike GLP-1 drugs, ERR agonists have no completed human trials.

Can you take SLU-PP-332 orally?

SLU-PP-332 is not orally bioavailable and has a short half-life, so in research it was injected. SLU-PP-915 was specifically designed to be orally active and works when given by mouth in mice. Neither compound has an established human oral dose — nobody has published human dosing data.

Are SLU-PP-332 and SLU-PP-915 safe or legal to buy?

They are unapproved experimental compounds sold only as "research chemicals," so there is no safety, purity or dosing oversight. Anti-doping agencies are already developing tests for them, meaning they would be banned in tested sport. There is no human safety data of any kind.

How is this different from MOTS-c?

MOTS-c is a mitochondrial-derived peptide, while SLU-PP-332/915 are synthetic nuclear-receptor agonists. Both get marketed as "exercise mimetics," but they act on completely different biology, and like SLU-PP-332/915, MOTS-c’s human evidence is very limited.

Peer-Reviewed References

Source 1
Synthetic ERRα/β/γ Agonist Induces an ERRα-Dependent Acute Aerobic Exercise Response and Enhances Exercise Capacity
ACS Chem Biol · 2023
PMID: 36988910
Source 2
A Synthetic ERR Agonist Alleviates Metabolic Syndrome
J Pharmacol Exp Ther · 2024
PMID: 37739806
Source 3
Novel Pan-ERR Agonists Ameliorate Heart Failure Through Enhancing Cardiac Fatty Acid Metabolism and Mitochondrial Function
Circulation · 2024
PMID: 37961903
Source 4
An orally active estrogen receptor-related receptor agonist, SLU-PP-915, enhances aerobic exercise capacity
J Pharmacol Exp Ther · 2026
PMID: 41421047
Source 5
In Vitro Metabolism and Analytical Characterization of SLU-PP-332 and SLU-PP-915: Novel Pan-ERR Agonists With Doping Potential
Rapid Commun Mass Spectrom · 2026
PMID: 41588687
Source 6
Targeting ERRs to counteract age-related muscle atrophy associated with physical inactivity: a pilot study
Front Physiol · 2025
PMID: 40692696
Source 7
The Estrogen Receptor-Related Orphan Receptors Regulate Autophagy through TFEB
Mol Pharmacol · 2024
PMID: 39168657
Source 8
Nuclear Receptor-Targeted Therapies: Reprogramming Metabolism with TRβ, ERRα, and LXR Modulators
Biomolecules · 2026
PMID: 41750342
⚠️ Disclaimer

Educational purposes only. Not medical advice.

SLU-PP-332 and SLU-PP-915 are unapproved experimental compounds with no human clinical data. Nothing here is a recommendation to buy, sell or use them.