SLU-PP-332 is a synthetic small-molecule pan-agonist of the three estrogen-related receptors (ERRα, ERRβ, and ERRγ), with reported EC50 values of approximately 98 nM, 230 nM, and 430 nM respectively, and it is used in laboratory research as a chemical probe for ERR-driven mitochondrial and oxidative-metabolism gene programs. Despite frequently being grouped with research peptides by suppliers and catalogs, SLU-PP-332 is not a peptide: it is a benzohydrazide small molecule, (E)-4-hydroxy-N'-(naphthalen-2-ylmethylene)benzohydrazide, with the molecular formula C18H14N2O2 and a molecular weight of 290.32 g/mol (CAS 303760-60-3). This article reviews its origin, mechanism, published experimental literature, and laboratory handling. As of 2026, SLU-PP-332 remains a pre-clinical research compound: the published record consists of cell-culture and rodent studies, and no registered human clinical trials of the compound have been reported.
What Is SLU-PP-332?
SLU-PP-332 emerged from medicinal-chemistry work at Saint Louis University and collaborating institutions aimed at solving a long-standing problem in nuclear-receptor pharmacology. Estrogen-related receptors are orphan nuclear receptors — structurally related to the classical estrogen receptor but not activated by estrogen — that act as transcriptional regulators of mitochondrial biogenesis, oxidative phosphorylation, and fatty acid metabolism. Genetic studies had implicated ERRα in skeletal-muscle exercise capacity, but while agonists selective for ERRβ and ERRγ (notably GSK4716) had been described, compounds with meaningful ERRα agonist activity proved difficult to design.
A 2020 study in Bioorganic Chemistry reported the structural strategy that solved this: by systematically modifying the GSK4716 scaffold, the authors engineered high-affinity ERRα agonism into a chemical series that had previously been ERRβ/γ-selective, producing the first ERRα/β/γ pan agonists intended as tools to probe ERR physiology. SLU-PP-332 is the best-characterized compound from that line of work. It has since been distributed as a reference standard by commercial chemical-biology suppliers and is commonly described in catalogs as a "pan-ERR agonist" or "exercise mimetic" research tool.
Is SLU-PP-332 a Peptide?
No. This is a frequent point of confusion because SLU-PP-332 is sold alongside research peptides and often appears in the same catalogs. Structurally it is a small aromatic hydrazone, not a chain of amino acids, and it does not act on a cell-surface receptor. It diffuses into cells and binds the ligand-binding domain of an intracellular nuclear receptor. That distinction matters practically: unlike lyophilized peptides, which are typically reconstituted in aqueous bacteriostatic water, SLU-PP-332 is poorly water-soluble and is generally dissolved in an organic solvent such as DMSO for in-vitro work.
Mechanism of Action
The estrogen-related receptors function as constitutively active transcription factors that bind ERR response elements in the promoters of genes governing cellular energy metabolism. SLU-PP-332 binds the ERR ligand-binding pocket and increases transcriptional output across all three subtypes, with the highest potency at ERRα. In the original characterization, molecular modeling indicated that the modified scaffold adopts a favorable binding mode within the ERRα pocket that the parent ERRβ/γ-selective compound does not.
Downstream, ERR activation upregulates genes associated with mitochondrial biogenesis, oxidative phosphorylation complexes, and fatty acid oxidation. In C2C12 skeletal-muscle cells, SLU-PP-332 treatment increased expression of pyruvate dehydrogenase kinase 4 (Pdk4), raised maximal mitochondrial respiration measured by extracellular flux analysis, and increased MitoTracker signal consistent with greater mitochondrial content.
A distinctive mechanistic finding is the involvement of Ddit4 (also known as REDD1), a stress-responsive gene induced by acute aerobic exercise. Chromatin immunoprecipitation sequencing in C2C12 cells identified ERRα binding sites near and within Ddit4, and induction of Ddit4 and Slc25a25 by SLU-PP-332 in primary myocytes was lost in ERRα-knockout cells but preserved in ERRγ-knockout cells — establishing that the acute transcriptional response is ERRα-dependent rather than a general pan-ERR effect.
Published Research Overview
The experimental literature on SLU-PP-332 is concentrated in four areas, all pre-clinical:
- Skeletal muscle and exercise-response transcription. The foundational characterization, published in ACS Chemical Biology in 2023 (volume 18, pages 756–771), reported that SLU-PP-332 activates all three ERRs with greatest potency at ERRα and has pharmacokinetic properties adequate for use as an in-vivo chemical tool. In mice, administration increased type IIa oxidative skeletal-muscle fibers and enhanced running endurance. RNA-sequencing of quadriceps and gastrocnemius muscle showed that the differentially expressed genes overlapped significantly with genes induced by a single bout of aerobic exercise, and endurance enhancement was abolished in muscle-specific ERRα-knockout mice.
- Whole-body metabolism. A 2024 study in the Journal of Pharmacology and Experimental Therapeutics (volume 388, pages 232–240) administered SLU-PP-332 to diet-induced obese and ob/ob mice and reported increased energy expenditure and fatty acid oxidation, reduced fat-mass accumulation, and improved insulin sensitivity in those animals.
- Cardiac metabolism. A 2024 report in Circulation examined SLU-PP-332 and the structurally distinct analogue SLU-PP-915 in the mouse transverse aortic constriction model of pressure-overload heart failure. In those mice, both compounds improved ejection fraction, reduced fibrosis, and increased survival without affecting cardiac hypertrophy. Multi-omics analysis attributed the transcriptional activation of fatty acid metabolism and mitochondrial genes primarily to ERRγ, and metabolomics showed normalization of fatty acid/lipid and TCA/OXPHOS metabolite profiles.
- Aging tissue models. A 2023 study in The American Journal of Pathology treated 21-month-old mice with a pan-ERR agonist for eight weeks and reported, in those animals, reversal of age-related increases in albuminuria and podocyte loss, along with improvements in mitochondrial function and inflammatory markers in the aging kidney, with effects the authors compared to those of lifelong caloric restriction.
These findings should be read as scientific context describing how SLU-PP-332 behaves in cell-culture and rodent systems. The evidence base is entirely pre-clinical; no human efficacy or safety data exist, and none of these observations establish any application outside the laboratory.
How Does SLU-PP-332 Differ From Metabolic Research Peptides?
SLU-PP-332 is mechanistically unrelated to the metabolic peptides commonly studied alongside it. Incretin-receptor peptides such as tirzepatide, retatrutide, survodutide, and cagrilintide act on cell-surface G protein-coupled receptors and are studied in the context of appetite and glucose-regulatory signaling. Mitochondrially derived peptides such as MOTS-c and mitochondria-targeted peptides such as SS-31 (elamipretide) act at or within the mitochondrion itself. SLU-PP-332, by contrast, works upstream at the level of transcription: it binds a nuclear receptor and alters which metabolic genes are expressed. In research design terms, this makes it useful for asking questions about transcriptional control of oxidative capacity rather than about receptor-level or organelle-level signaling. Its closest functional comparators in the literature are other transcription-targeting metabolic tool compounds such as AICAR (an AMPK activator) and PPARδ agonists.
Storage & Handling
Dynamite Research Peptides supplies SLU-PP-332 as a lyophilized powder (5 mg, research code YPB.243). Store the powder at -20°C or below, protected from light and moisture. Because the compound is a hydrophobic small molecule rather than a peptide, it is typically prepared as a concentrated stock in DMSO — reported solubility is approximately 29 mg/mL (100 mM) in DMSO — and diluted into assay media immediately before use. Avoid repeated freeze-thaw cycles of stock solutions, and confirm identity and purity against the Certificate of Analysis (COA) before use. Handle with appropriate personal protective equipment in a well-ventilated laboratory area.
Conclusion
SLU-PP-332 is a well-characterized chemical probe for estrogen-related receptor biology and one of the few available tools with genuine ERRα agonist activity, which is why it appears across published studies of skeletal-muscle oxidative capacity, whole-body energy metabolism, cardiac metabolic remodeling, and aging tissue models. Its value in the laboratory lies in enabling pharmacological tests of ERR function that were previously only possible through genetic manipulation. Our SLU-PP-332 is high-purity, third-party tested, and ships with documentation so experimental results stay reliable and reproducible.
Frequently Asked Questions
What receptor does SLU-PP-332 target?
SLU-PP-332 is a pan-agonist of the estrogen-related receptors ERRα, ERRβ, and ERRγ — orphan nuclear receptors that regulate transcription of mitochondrial and oxidative-metabolism genes. Reported EC50 values are approximately 98 nM (ERRα), 230 nM (ERRβ), and 430 nM (ERRγ), making ERRα its most potent target.
Is SLU-PP-332 a peptide?
No. It is a synthetic small molecule — a benzohydrazide with the formula C18H14N2O2 and molecular weight 290.32 g/mol — despite commonly being catalogued alongside research peptides. It acts on an intracellular nuclear receptor rather than a cell-surface peptide receptor.
Why is SLU-PP-332 described as an "exercise mimetic" in the literature?
The term comes from a 2023 ACS Chemical Biology study reporting that, in mice, the compound induced a skeletal-muscle gene-expression program overlapping significantly with the transcriptional response to a single bout of aerobic exercise, and that this response required ERRα. It is a description of a transcriptional pattern observed in rodent muscle, not a claim about any human application.
Have there been human clinical trials of SLU-PP-332?
Based on the published literature available as of 2026, no. All reported efficacy data come from cell-culture and mouse studies. Recent 2026 publications have focused on structure–activity relationships and analytical/metabolite characterization rather than clinical evaluation.
How is SLU-PP-332 dissolved for laboratory work?
Unlike lyophilized peptides, it is not readily water-soluble. Published and supplier data indicate solubility of roughly 29 mg/mL (100 mM) in DMSO, which is the standard route for preparing in-vitro stock solutions.
What is the purity level of Dynamite Research Peptides' SLU-PP-332?
Our SLU-PP-332 is typically 99%+ pure, verified by analytical testing. Detailed purity data is provided on the Certificate of Analysis (COA) available for each product.
All products are for research use only — not for human or animal consumption. Nothing in this article describes or endorses any human, therapeutic, or dietary application.