Not FDA-approved · Early research compound · No human clinical trials · Research chemical
Human evidence
None — preclinical only as of May 2026
Preclinical evidence
Moderate — compelling initial data from developing lab; limited independent replication
EDUCATIONAL TOOL — NOT MEDICAL ADVICE
What is SLU-PP-332?
SLU-PP-332 is an exercise mimetic that works through a different mechanism than AICAR or MOTS-c. Where those compounds activate AMPK — which then drives downstream exercise adaptation genes — SLU-PP-332 activates ERRα (estrogen-related receptor alpha) and ERRγ directly. ERRα and ERRγ are transcription factors that control the expression of hundreds of genes involved in mitochondrial biogenesis, oxidative metabolism, and endurance adaptation. They're downstream of AMPK and PGC-1α in the exercise signaling cascade — but SLU-PP-332 hits them directly without needing the upstream AMPK activation.
The preclinical results from the Burris lab at Saint Louis University were striking: sedentary mice treated with SLU-PP-332 for 4 weeks showed significant improvements in running capacity — alongside increased mitochondrial density in muscle, improved fat oxidation, and better metabolic profiles. The compound also showed benefits in a heart failure model, where ERRα/γ activity declines as the failing heart shifts from fat to glucose as its primary fuel.
The honest picture: compelling initial preclinical data from a single lab, no independent replication published, zero human data. SLU-PP-332 is earlier-stage than even MOTS-c in the evidence hierarchy. It's being used by biohackers based on the initial papers alone — with the appeal being a genuinely different mechanistic entry point that may stack additively with AMPK activators like AICAR and MOTS-c.
How it works
ERRα/γ Activation — Direct Transcription of Exercise Genes
Estrogen-related receptors α and γ (ERRα, ERRγ) are orphan nuclear receptors — transcription factors that bind DNA and control gene expression without requiring a natural hormone ligand. They regulate hundreds of genes involved in: mitochondrial biogenesis (via PGC-1α coactivation), oxidative phosphorylation enzyme expression, fatty acid oxidation, and glucose metabolism. ERRα activity is essential for exercise adaptations in skeletal muscle and cardiac muscle — ERRα knockout mice have severely impaired exercise capacity, less than 50% of wild-type running distance.
How SLU-PP-332 Differs from AICAR and MOTS-c
The exercise cascade runs: AMPK activation → PGC-1α upregulation → ERRα/γ coactivation → exercise gene expression. AICAR activates AMPK (upstream, via ZMP). MOTS-c activates AMPK (upstream, via folate cycle). SLU-PP-332 bypasses all of that and directly activates ERRα/γ — the transcription factors at the downstream end. This means SLU-PP-332 can drive exercise gene expression in contexts where upstream AMPK signaling may be blunted — and may produce additive effects when combined with AMPK activators, since different steps of the same cascade are being targeted.
Cardiac Application
In heart failure, the failing heart progressively loses its ability to use fatty acids as fuel and becomes dependent on glucose — a metabolically less efficient state. ERRα/γ activity drives fatty acid oxidation capacity in cardiomyocytes. SLU-PP-332 in heart failure models improved cardiac metabolic efficiency and function by restoring ERRα/γ-driven fat oxidation. This cardiac mechanism is independent of and distinct from hexarelin's CD36/GHS-R1b cardioprotective approach.
What the research shows
NOTE — HUMAN EVIDENCE: NONE. PRECLINICAL ONLY, PRIMARILY FROM DEVELOPING LAB.
STUDYCell Reports · 2023
SLU-PP-332 activates ERRα/γ and mimics exercise adaptations in mice
Kim JY et al.
Sedentary mice, 4 weeks SLU-PP-332. Significant improvement in treadmill endurance, increased mitochondrial density in skeletal muscle, improved fat oxidation, reduced adiposity. ERRα/γ mechanism confirmed. Primary preclinical paper from the developing lab.
ERRα is required for endurance exercise capacity and metabolic adaptation
Huss JM et al.
ERRα knockout mice have less than 50% of wild-type running capacity. Confirms ERRα's essential role in exercise adaptation and validates it as a target for exercise mimetics.
✓ERRα/γ activation mechanism confirmed — direct transcription factor agonism
✓Preclinical endurance improvement in sedentary mice (Cell Reports 2023)
✓Mitochondrial biogenesis in skeletal muscle confirmed
✓ERRα essential for exercise capacity — knockout mouse data
?UNCERTAIN
?Human translation — completely unknown (no clinical trials)
?Safe human dose and pharmacokinetics
?Independent replication outside the developing lab
?Long-term metabolic effects and safety
What the community reports
—Improved endurance — consistent with preclinical data; most compelling reported effect; increased time to exhaustion and aerobic capacity
—Stack with AICAR or MOTS-c — the different mechanism makes combination theoretically additive; community actively exploring this
—Very early community — most users are running it based on the Cell Reports paper with appropriate epistemic humility about the evidence level
—Clean reported side-effect profile so far — but sample size is small and duration of use limited
Common misconceptions
"SLU-PP-332 is the same as AICAR."
REALITY
Different mechanism. AICAR activates AMPK which eventually activates ERRα. SLU-PP-332 activates ERRα directly — skipping the AMPK step. These are different parts of the same exercise signaling cascade, potentially additive when combined, not redundant.
"The mouse study proves it works in humans."
REALITY
Single lab, sedentary mice, no independent replication, zero human data. The mechanism is compelling; human translation is completely unknown. More caution warranted here than with AICAR, which at least has human PK/PD and safety data from McArdle disease and cardiac research.
EXERCISE MIMETIC CASCADE — STACKABLE MECHANISMS
SLU-PP-332: direct ERRα/γ activation (downstream). AICAR: AMPK via ZMP (upstream) → PGC-1α → ERRα. MOTS-c: AMPK via folate cycle (upstream, different mechanism) → same downstream path. Stacking SLU-PP-332 with AICAR or MOTS-c targets multiple steps of the same cascade — theoretically additive.
RECONSTITUTION CALCULATOR
EDUCATIONAL TOOL — NOT MEDICAL ADVICE · VERIFY WITH YOUR CLINICIAN
AI COACH PREVIEW
I'm stacking SLU-PP-332 with AICAR. What timing makes sense for these two exercise mimetics?
This is one of the most mechanistically interesting stacks in the exercise mimetic space — let me explain the rationale and give you practical timing guidance. Why this combination makes sense: The exercise adaptation cascade runs AMPK → PGC-1α → ERRα/γ → exercise gene expression. AICAR activates AMPK directly via ZMP. SLU-PP-332 activates ERRα/γ directly, skipping the AMPK/PGC-1α steps. You're hitting the cascade at two independent points. If AMPK activation is sufficient but ERRα/γ activation is rate-limiting, SLU-PP-332 fills the gap. If ERRα/γ is at capacity but upstream AMPK signaling could be amplified, AICAR fills that gap. They're additive in theory because they're not competing for the same receptor. Protocol thinking: AICAR: 250–500 mg SC before exercise or morning. SLU-PP-332: 5–20 mg SC — community-derived, no established human dose. Timing together: take both 30–60 minutes before training or in the morning. The AMPK activation from AICAR and the direct ERRα/γ activation from SLU-PP-332 both want to coincide with the active metabolic period. What to track: establish baseline endurance metric before starting (time trial distance, VO2 proxy, time to exhaustion at fixed intensity). Track weekly. Also: perceived exertion at fixed workloads and recovery quality between sessions. If you're adding SLU-PP-332 on top of existing AICAR, run 2 weeks of AICAR alone first so you know your AICAR baseline, then add SLU-PP-332 and track the delta. Important caution: SLU-PP-332 has zero human data. AICAR at least has human PK/PD from McArdle disease and cardiac research. SLU-PP-332 is being dosed based on preclinical extrapolation only. Are you already established on AICAR, or starting both simultaneously?
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