SLU-PP-332: The Complete Guide to the Pan-ERR Agonist Exercise Mimetic

Quick Facts

What SLU-PP-332 Does & How It Works

What It Does - Functional Outcomes

• Increases the rate at which the body burns fat as fuel, shifting energy metabolism away from carbohydrates toward fatty acid oxidation
• Triggers mitochondrial biogenesis (the production of new mitochondria inside muscle cells), increasing cellular energy production capacity
• Reproduces key gene expression changes that aerobic exercise training produces in skeletal muscle, without physical activity
• Improves markers of insulin sensitivity and glucose handling in obese animal models
• Promotes the formation of type IIa oxidative muscle fibers - the fiber type associated with endurance capacity
• Supports cardiac energy metabolism, with documented cardioprotective effects in a heart failure model
• Activates cell survival and anti-atrophy pathways in muscle cell models relevant to age-related muscle loss

How It Works - Mechanism of Action

Pan-ERR Receptor Activation (Evidence: In vitro, confirmed)

SLU-PP-332 binds to and activates all three isoforms of the estrogen-related receptor (ERR) family: ERRalpha, ERRbeta, and ERRgamma. ERRs are orphan nuclear receptors, meaning they have no known natural ligand that activates them. Despite the name, ERRs are not the same as estrogen receptors and do not bind estrogen. They are master regulators of oxidative metabolism and mitochondrial function. ERRalpha expression rises naturally in response to exercise in healthy individuals, and SLU-PP-332 pharmacologically mimics that activation. ERRalpha is the primary target, with an EC50 of 98 nM (the concentration needed to produce half the maximum effect) - ERRalpha is activated 4.4-fold more potently than ERRgamma and 2.3-fold more potently than ERRbeta.

ERRalpha-Dependent Gene Program Activation (Evidence: In vitro - ; )

Once ERRalpha is activated, a cascade of gene expression changes follows. SLU-PP-332 upregulates PGC-1alpha (the master regulator of mitochondrial biogenesis), along with GLUT4 (glucose transporter), uncoupling proteins involved in thermogenesis, and PDK4 in skeletal muscle cells. It also upregulates DDIT4 (DNA Damage Inducible Transcript 4) - a gene specifically induced by the acute exercise program - within 2 hours of treatment. This DDIT4 induction is ERRalpha-specific: remove ERRalpha from the cells and the response disappears entirely. The downstream effect is a shift in cellular programming that mirrors what weeks of aerobic training produce.

Mitochondrial Biogenesis and Oxidative Metabolism Shift (Evidence: In vitro - multiple studies)

SLU-PP-332 increases mitochondrial DNA by 2.5-fold in C2C12 skeletal muscle cells (a standard mouse skeletal muscle cell line used in exercise biology research). It also increases cellular respiration rates and drives the formation of type IIa oxidative muscle fibers. These fibers are the ones most associated with aerobic endurance capacity. Alongside structural changes in muscle, the compound reduces the Respiratory Exchange Ratio in animal models - a direct measure confirming the body is burning proportionally more fat and less carbohydrate. Fatty acid oxidation increased by approximately 25% and resting energy expenditure increased by approximately 12% in the primary obesity model.

Coactivator Recruitment Amplification (Evidence: In vitro - Jones et al., JPET, 2024)

Binding to a receptor is only step one. The signal has to be amplified into actual gene expression changes through the recruitment of coactivator proteins - helper molecules that amplify the transcriptional signal. Jones and colleagues documented that SLU-PP-332 enhances coactivator recruitment to the ERR complex upon binding. This amplification helps explain why a compound with a relatively modest receptor binding potency (EC50 of 98 nM, the concentration needed to produce half the maximum effect) can drive the substantial physiological changes observed in animal models. The binding triggers a signal that gets louder through this coactivator recruitment step.

SLU-PP-332 Molecular Profile

Structure reference: View SLU-PP-332 on PubChem - Publishing team: retrieve 2D structure image from this link.

A note on classification: SLU-PP-332 has no amino acid sequence because it is not a peptide by any biochemical definition. It is a non-peptidic hydrazide small molecule. The "peptide compound" framing used in wellness and research pharmacy contexts reflects market categorization convention - this guide uses that framing in its title but is accurate about the compound's actual chemistry throughout.

SLU-PP-332 Uses & Benefits

Metabolic Syndrome and Obesity

SLU-PP-332 is most actively researched as a metabolic intervention for obesity and metabolic syndrome, specifically as a tool for increasing fat oxidation and energy expenditure in contexts where physical exercise is limited or impossible. The mechanism is direct: ERRalpha activation drives upregulation of fatty acid oxidation enzymes, glucose transporters, and mitochondrial biogenesis genes, producing measurable changes in substrate utilization. In diet-induced obese mice, 28 days of treatment produced a 12% reduction in body weight and a 10-fold reduction in fat accumulation relative to untreated controls. It also improved insulin sensitivity, improved glucose tolerance, and reversed established hepatic steatosis, all without changes in food intake or activity. (Evidence: Preliminary - animal only - )

Exercise Endurance Enhancement

The endurance application drives much of the community interest in SLU-PP-332. In normal-weight mice, the compound produced a 70% improvement in run time and 45% improvement in run distance compared to untreated controls. These effects were mediated through ERRalpha-dependent oxidative fiber formation, increased capillary density, and enhanced mitochondrial function. These gains were observed in sedentary, untrained animals. Whether the compound adds to the adaptations of trained individuals, or primarily replicates a training effect in those who cannot train, is an open question the research has not addressed. The DDIT4 induction within 2 hours confirms the compound is triggering the acute exercise gene response at the cellular level. (Evidence: Preliminary - animal only - ; )

Cardiovascular Disease and Heart Failure

The cardiac application of SLU-PP-332 is distinct from the metabolic and endurance research and addresses a specific pathological mechanism. The failing heart loses its ability to efficiently oxidize fat as fuel - it becomes metabolically compromised in a way that compounds its mechanical dysfunction. SLU-PP-332's ERR activation restores cardiac fatty acid oxidation capacity. In a pressure overload mouse model of heart failure, treatment improved ejection fraction, improved contractility, reduced fibrosis, reduced cardiomyocyte cell death, and increased survival. This positions the compound as a potential metabolic rescue approach for a disease where current therapies primarily target mechanical and neurohormonal pathways rather than the underlying energy metabolism deficit. (Evidence: Preliminary - animal only)

Sarcopenia and Age-Related Muscle Atrophy

The sarcopenia application is the most recent and least developed research direction. A 2026 study examined SLU-PP-332 in primary muscle cells under atrophy-modeling conditions, documenting upregulation of PGC-1alpha, SIRT1, Akt, Bcl-2, and FNDC5, downregulation of NOX4, and promotion of myoblast proliferation and differentiation at 10 micromolar concentration. These are relevant targets for age-related muscle loss: cell survival signals, mitochondrial protective pathways, and reduced oxidative stress. The in vitro context means the gap to human application is especially wide here. (Evidence: Preliminary - in vitro - )

Where This Guide Comes From

SLU-PP-332 Results & Timelines

A note on this section before the timelines: SLU-PP-332 is unusual compared to most compounds in the MPP library in that the gap between animal research timelines and human community timelines is not just a translation problem - it is also a route-of-administration problem. The published mouse data used intraperitoneal injection (delivery directly into the peritoneal cavity) at high doses. The most commercially accessible human format is oral capsule, which the research has confirmed has poor bioavailability. The timelines below draw from both sources and note which is which.

Fat Loss and Metabolic Changes

• Week 1-2: In mouse studies, measurable reductions in Respiratory Exchange Ratio (a shift toward fat burning) were observed early in the treatment period. Community reporters sometimes note a subjective increase in warmth or energy expenditure in the first 1-2 weeks of use.
• Week 3-4: In the primary 28-day obesity study, fat mass reductions were measurable and significant by the end of the study period. Community reports of visible body composition changes cluster in this window, most commonly in combination with maintained caloric intake.
• Week 4-8: Community-reported plateau or maintenance of fat loss effects for those who observe initial responses. Some reporters cycle off at this point per common community protocol.
• Beyond 8 weeks: No published research covers durations beyond 28 days. Long-term metabolic effects in any species are unknown.

Endurance and Physical Performance

• Week 1-2: In mouse studies, gene expression changes including DDIT4 induction were observed within 2 hours of treatment. Structural changes in muscle fiber composition take longer to manifest. Some community users report subjective early improvements in aerobic feel or recovery, though these reports are uncontrolled.
• Week 2-4: Oxidative fiber formation and capillary density increases in the mouse studies were assessed after the full treatment period rather than at interim timepoints. Community reports of meaningful endurance changes cluster around weeks 3-5.
• Week 4-8: Community documentation most commonly places peak reported performance effects in this range.

Cardiovascular and Energy Metabolism

• Days 1-3: The DDIT4 acute exercise gene program induction was confirmed within 2 hours of cell treatment - the earliest documented molecular response.
• Week 2-4: Heart failure model outcomes including ejection fraction improvements were assessed across the full treatment duration - no interim data on the timeline of cardiac effects in the mouse model.

How to Administer SLU-PP-332

Intraperitoneal Injection (Animal Research Standard)

Every published efficacy study on SLU-PP-332 used intraperitoneal injection, meaning delivery directly into the peritoneal cavity of the animal. This is the research-validated route for this compound in the animal model context. Intraperitoneal injection is not a standard human administration route and is not relevant to human use outside specific clinical settings. It is documented here because it is the route behind all the efficacy data - understanding that the published results came from this route, and not from oral administration, is essential context for evaluating the research.

Subcutaneous Injection (SubQ)

SubQ injection is not specifically documented in published efficacy research for SLU-PP-332. Some community sources discuss SubQ use as a practical alternative to intraperitoneal injection, based on the reasoning that injectable delivery avoids the oral bioavailability limitation. No bioavailability or efficacy data comparing SubQ to intraperitoneal delivery has been published for this compound.

Oral - Capsule and Powder

Oral capsule and powder forms are the most commercially accessible formats and are widely used in community contexts. The critical pharmacological fact for this route: published research confirmed that SLU-PP-332 has poor oral bioavailability. A meaningful portion of an orally administered dose is metabolized before reaching systemic circulation. This is not a minor caveat - it is significant enough that the research team at Saint Louis University developed an entirely new compound (SLU-PP-915) specifically to address this limitation. No peer-reviewed efficacy study has used oral administration for SLU-PP-332. Community reports of effects via oral capsule do exist, but they cannot be directly attributed to the bioavailability-limited oral route versus other factors without controlled data.

Injectable Liquid

Commercial injectable liquid formulations of SLU-PP-332 are available at various concentrations. These are not manufactured under GMP (Good Manufacturing Practice) standards or sterility conditions required for human injectable compounds. The injectable format is more consistent with the animal study methodology than oral formulations, but the specific injection route for human use and the bioavailability profile for these routes remain unstudied in published literature.

SLU-PP-332 Dosage & Cycle Length

Overall dosing range: No established human dosing protocol exists. Animal studies used 50 mg/kg intraperitoneal injection twice daily. Community sources cite a range of approximately 200 mcg to 1.5 mg per day in various formulations - entirely unvalidated in any clinical setting.

Important: The 50 mg/kg figure above is an animal study dose. Animal mg/kg doses cannot be translated into human doses and must not be used for any calculation.

This is a compound where the gap between animal study dosing and human community practice is especially large and worth understanding clearly. The mouse studies that produced the striking endurance and fat-loss results used intraperitoneal injection at 50 mg/kg twice daily. The community dosing figures circulating in wellness contexts are extrapolated, not established, and the route most supported by the research (injection) carries confirmed advantages over the most commercially accessible route (oral capsule) for reasons detailed in the Administration section.

How the goal context shifts where community sources land:

• Low end of range (200-500 mcg/day): Most commonly cited in wellness and practitioner guides for general metabolic support, energy expenditure, and body composition goals
• Mid range (500 mcg to 1 mg/day): Cited in community sources for combined fat-loss and endurance applications; some sources describe split dosing across two daily administrations
• High end of range (1-1.5 mg/day): Referenced in some community discussions for more aggressive metabolic applications; no additional evidence of efficacy or safety at higher doses compared to the low end

Frequency: Community sources most commonly cite once or twice daily dosing. Split dosing (two administrations per day) is sometimes recommended to account for an estimated half-life of approximately 6 hours cited in non-peer-reviewed sources - this half-life figure has not been confirmed in published pharmacokinetic research.

Cycle length: 4-8 weeks on, followed by an equivalent off period, is the most commonly circulated pattern in community documentation. Some vendor sources suggest the compound does not require cycling. Neither position is supported by clinical evidence.

Loading protocols: No loading protocols are documented in published research or consistently described in community sources. Not applicable based on available data.

The honest picture on dosing: Every dosing figure in this section that applies to humans comes from wellness guides, commercial vendor documentation, and community discussion - not peer-reviewed clinical research. The University of Florida research team has publicly stated that further animal testing is needed before human trials can begin. For a compound at this stage of research, the dosing section of any guide is necessarily a documentation of what the community currently discusses, not a validated protocol. Treat all figures here accordingly.

SLU-PP-332 Vial Sizes, Costs & Quality

Common product formats: SLU-PP-332 is sold commercially in three primary formats: powder, injectable liquid, and oral capsule. This differs from most compounds in the MPP library that are primarily available as lyophilized powder vials for reconstitution.

• Powder: Available in quantities ranging from 1 g to 100 g and above from chemical supply vendors
• Injectable liquid: Available in 30 mL vials at concentrations including 500 mcg/mL and 100 mg/mL
• Oral capsules: Available at 1 mg per capsule from some research chemical vendors
• Combination products: Some vendors offer SLU-PP-332 combined with other compounds in capsule form

Typical cost range: Injectable liquid formats are priced approximately $50-$100 per 30 mL vial for U.S.-available products at current market pricing. Oral capsule formats vary by vendor and quantity. Powder pricing varies substantially with quantity. Costs reflect significant variation by format, concentration, vendor, and purity specifications.

Storage - powder form:

• Temperature: 2-8 degrees C for typical storage; some suppliers specify -20 degrees C for long-term storage
• Shelf life: Stable under recommended conditions per manufacturer specification - varies by vendor
• Light sensitivity: Protect from prolonged light exposure; standard practice for research chemicals

Storage - liquid/solution form:

• Temperature: -10 degrees C recommended by some vendors for liquid formulations
• Use window: Solution stability is limited once prepared; suppliers advise using solutions promptly rather than storing long-term

Normal appearance: SLU-PP-332 powder is a white to off-white solid. Injectable liquid solutions should appear clear to slightly yellow and free of visible particulates. Unlike classical peptides, this compound is a non-peptidic small molecule - its appearance and stability characteristics follow small-molecule chemistry rather than peptide chemistry.

Signs of degradation: Visible cloudiness, particulate matter, significant discoloration beyond a pale yellow, or unusual odor may indicate compromised product quality. Degraded or contaminated compounds should not be used.

Quality Considerations

What separates a responsibly manufactured product from a problematic one comes down to the testing behind it. Purity verification matters: third-party testing by reversed-phase HPLC to at least 98% purity, documented endotoxin levels below 0.1 EU/mg, and a chain of custody that traces the product back to its synthesis. Overseas chemical suppliers can list "greater than 98% purity" without the infrastructure to verify it independently - there is no regulatory body requiring them to back that claim with documented methodology. U.S.-based manufacturers working to documented manufacturing standards offer meaningfully more accountability, and the cost difference reflects that. For injectable formats in particular, the sourcing decision carries direct physical risk that powder or capsule formats do not - impurity and sterility failures in an injectable product go directly into the body with no filter in between.

SLU-PP-332 Side Effects & Safety

The safety picture for SLU-PP-332 is defined first and foremost by what does not exist: no human safety data of any kind. The University of Florida research team has publicly stated that additional animal safety testing is needed before human trials can be designed. What follows is an honest accounting of what preclinical studies and community experience have documented, with the appropriate caveat that neither source is a substitute for controlled human safety research.

Side Effect Spectrum

Contraindications

No validated, evidence-based contraindications have been established. SLU-PP-332 has no completed human safety program. The following reflect reasonable extrapolations from the compound's mechanism and preclinical profile:

• Active cardiovascular disease: Insufficient data to confirm safety; ERR activation affects cardiac energy metabolism in ways that may have unpredictable consequences in pathological cardiac states beyond the studied heart failure model
• Hepatic dysfunction: Minor liver enzyme changes were observed in mouse studies; insufficient data to confirm safety in individuals with pre-existing liver disease
• Hormone-sensitive conditions: ERRs are structurally related to estrogen receptors, though they do not bind estrogen. The clinical significance of ERR agonism in individuals with hormone-sensitive cancers or other hormone-sensitive conditions has not been studied
• Any significant medical condition: Insufficient data to confirm safety across any human population

Populations Where Caution Is Warranted

• Pregnancy and breastfeeding: No safety data whatsoever; use is not appropriate without medical supervision
• Pediatric use: Not studied in pediatric populations; not appropriate without medical supervision
• Individuals on lipid-modifying medications: Minor cholesterol effects observed in mouse studies suggest a potential interaction with lipid management regimens; no data to define this interaction
• Individuals with metabolic or hepatic conditions: The compound's mechanism affects substrate utilization and liver metabolism; effects in individuals with pre-existing metabolic disease outside the studied models are unknown

Red Flags - Stop Use and Seek Medical Attention If:

• Significant liver enzyme elevation detected in blood work
• Unusual cardiac symptoms including palpitations, chest discomfort, or shortness of breath
• Severe gastrointestinal distress, jaundice, or dark urine
• Any unexpected hormonal changes or symptoms not explained by other causes
• Signs of injection-site infection including increasing redness, warmth, swelling, or discharge

Drug and Compound Interactions

No drug interactions have been documented in published research for SLU-PP-332, because no human research has been conducted. Given its effects on fatty acid oxidation and glucose metabolism, interactions may theoretically exist with lipid-modifying medications, insulin or glucose-managing drugs, and compounds that affect mitochondrial function. Some community sources describe combining SLU-PP-332 with urolithin A and BAM15, and one commercial combination product (SLU-PP-332 with BAM15) is available commercially, but no mechanistic or safety data on these combinations has been published in peer-reviewed research. The absence of documented interactions should not be interpreted as confirmed safety - it reflects the absence of research, not the absence of risk.

SLU-PP-332 Research & Studies

SLU-PP-332 has accumulated a meaningful body of preclinical research since its initial development at Saint Louis University and the University of Florida. Multiple independent research groups have documented exercise-mimetic, metabolic, and cardioprotective effects through ERR pathway activation. What makes honest appraisal essential is that the evidence base is entirely preclinical - cell lines and mouse models. The compound has never been tested in a human clinical trial. That context frames everything in this section.

Pharmacokinetics & Metabolism

Absorption and Bioavailability All pharmacokinetic efficacy data from published research comes from mouse models using intraperitoneal injection. Published research confirmed that SLU-PP-332 has poor oral bioavailability - a significant limitation that drove development of the successor compound SLU-PP-915. No published human pharmacokinetic data exists for any administration route.

Distribution Tissue distribution data specific to SLU-PP-332 has not been published in peer-reviewed literature. Documented effects in skeletal muscle, cardiac tissue, and liver across different study models suggest systemic distribution following injection, but tissue concentration data by organ has not been characterized.

Half-Life An approximate half-life of 6 hours is cited in community and non-peer-reviewed wellness sources. This figure does not appear in published pharmacokinetic research and should be treated as an estimate rather than a confirmed measurement.

Metabolism and Elimination A 2026 study used human liver S9 fractions and human liver microsomes to characterize SLU-PP-332 metabolism in vitro (in a laboratory setting using human liver tissue, not in a living person). The researchers used LC-HRMS/MS methodology (liquid chromatography high-resolution mass spectrometry, a technique that identifies chemical compounds by their molecular weight and fragmentation patterns) to identify nine total metabolites. These broke down into 6 Phase-I metabolites (direct chemical modifications the liver makes to the compound) and 3 Phase-II conjugates (a second processing step where the liver attaches additional molecules to aid elimination). This research was developed to support anti-doping detection protocols for competitive sports testing.

The half-life, tissue distribution, and in vivo pharmacokinetic profile of SLU-PP-332 in any species beyond the mouse intraperitoneal injection model remain incompletely characterized in published literature.

Mechanistic Research

Direct ERRalpha Binding Confirmation (Evidence: In vitro - Merches et al., ACS Chemical Biology, 2022)

Merches and colleagues confirmed that SLU-PP-332 directly binds ERRalpha using a limited proteolysis assay (a technique that detects whether a compound has physically attached to a receptor by measuring how the receptor's shape changes). This established the mechanistic foundation for its classification as a pan-ERR agonist. The same study identified a limitation: ERRalpha fails to produce a signal in differential scanning fluorimetry, meaning not all standard binding assays detect this interaction. ERRgamma also failed the limited proteolysis assay, leaving the ERRgamma binding profile incompletely characterized.

Enhanced Coactivator Recruitment (Evidence: In vitro - Jones et al., Journal of Pharmacology and Experimental Therapeutics, 2024)

Jones and colleagues documented that SLU-PP-332 enhances recruitment of transcriptional coactivator proteins to the ERR receptor complex upon binding. Coactivator recruitment amplifies the transcriptional signal - it translates receptor activation into actual changes in gene expression. This helps explain why a relatively modest receptor binding potency (EC50 of 98 nM, the concentration needed to produce half the maximum effect) can produce the substantial downstream physiological effects observed in animal models.

Rapid Exercise Gene Program Induction via DDIT4 (Evidence: In vitro - ; )

DDIT4 (DNA Damage Inducible Transcript 4) is a gene specifically induced by the acute exercise gene program in skeletal muscle. It is upregulated within 2 hours of SLU-PP-332 treatment in C2C12 myocytes (mouse skeletal muscle cells used in exercise biology research). This mirrors what happens in human skeletal muscle within hours of aerobic exercise. The response is ERRalpha-specific: knockdown of ERRalpha in the cells eliminated the response entirely. This confirms SLU-PP-332 specifically activates the ERRalpha-dependent transcriptional program that exercise training drives, rather than stimulating metabolism through a broader or non-specific pathway.

Mitochondrial Biogenesis and Oxidative Metabolism (Evidence: In vitro - multiple studies)

Multiple cell studies documented that SLU-PP-332 increases mitochondrial DNA by 2.5-fold in skeletal muscle cells and increases cellular respiration rates. It also upregulates PGC-1alpha (Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha), the master regulator of mitochondrial biogenesis. These findings are mechanistically interconnected: ERRalpha activation drives PGC-1alpha expression, which coordinates the production of new mitochondria and upregulates the enzymatic machinery required for oxidative phosphorylation (the process cells use to generate energy from oxygen and fuel).

Condition-Focused Research

Metabolic Syndrome and Obesity {#research-metabolic}

The primary metabolic study used diet-induced obese mice and ob/ob mice (a genetic mouse model of severe obesity). Mice were treated with 50 mg/kg SLU-PP-332 by intraperitoneal injection twice daily for 12-28 days at thermoneutrality. Key findings included a 25% increase in fatty acid oxidation, a 12% increase in resting energy expenditure, and a 12% reduction in body weight over 28 days. Fat accumulation was reduced 10-fold relative to vehicle-treated controls. Insulin sensitivity improved, glucose tolerance improved, and established hepatic steatosis was reversed. A shorter 3-week cohort in the same study found no effect on glucose tolerance - a null result that serves as a useful reminder that outcomes depend on study duration and context. (Evidence: Preliminary - animal only)

Endurance and Physical Performance {#research-endurance}

The endurance study examined normal-weight mice and C2C12 myocytes. Treated mice ran 70% longer and 45% farther than untreated controls. Skeletal muscle analysis showed increased type IIa oxidative fiber formation, increased capillary density, and enhanced mitochondrial respiration - all mediated through the ERRalpha-dependent gene program. These effects were observed in sedentary, untrained animals. Whether the compound adds to the adaptations of trained individuals is unknown and has not been studied. Dedicated cluster articles cover the endurance mechanisms and the exercise biology in greater depth. (Evidence: Preliminary - animal only)

Cardiovascular Disease and Heart Failure {#research-cardiac}

The cardiac study used a pressure overload mouse model of heart failure - a standard model where mechanical stress is applied to the heart to induce failure-like conditions. SLU-PP-332 treatment improved ejection fraction, cardiac contractility, reduced fibrosis, reduced cardiomyocyte apoptosis (programmed cell death), and increased survival compared to untreated controls. The mechanism centered on restoring cardiac fatty acid oxidation capacity via ERRalpha/beta/gamma activation - a key metabolic deficit in the failing heart that most current therapies do not address. (Evidence: Preliminary - animal only)

Sarcopenia and Age-Related Muscle Atrophy {#research-sarcopenia}

A 2026 study examined SLU-PP-332 in primary muscle cells under atrophy-modeling conditions. At 10 micromolar concentration, the compound promoted myoblast proliferation and differentiation, upregulated PGC-1alpha, SIRT1, ERRalpha, FNDC5, Akt, and Bcl-2, and downregulated NOX4. The upregulation of Akt and Bcl-2 reflects activation of cell survival pathways relevant to preventing muscle wasting. The in vitro context means the gap to human application is especially wide. This is a promising direction that requires animal and eventually human research to determine whether the effect holds in a living system. (Evidence: Preliminary - in vitro)

Anti-Doping Detection Research {#research-doping}

A 2026 study used human liver S9 fractions and human liver microsomes to identify nine SLU-PP-332 metabolites (6 Phase-I metabolites and 3 Phase-II conjugates) using LC-HRMS/MS methodology. The research was designed specifically to support anti-doping detection protocols for competitive sports testing. The identification of specific metabolite signatures provides the basis for urine testing. The existence of this research reflects active monitoring by the anti-doping community running in parallel with the therapeutic research track.

Safety and Tolerability Research

The primary obesity model study treated obese mice with 50 mg/kg intraperitoneal injection twice daily for up to 28 days and reported no severe adverse events, no liver toxicity, no kidney toxicity, no cardiac toxicity, and no changes in pancreatic islet structure. Minor changes in plasma cholesterol and liver enzymes were noted but not characterized as clinically significant. The heart failure study documented a net cardioprotective profile. No chronic toxicology studies, reproductive or developmental toxicology studies, carcinogenicity studies, or genotoxicity studies have been published for SLU-PP-332. Maximum published study duration is 28 days in mice.

Research Limitations

SLU-PP-332 has no published human data of any kind - no pharmacokinetic studies, no dose-escalation trials, no efficacy studies, no safety studies. The entire evidence base consists of mouse models and cell culture experiments. Maximum study duration is 28 days in any species, meaning nothing is known about chronic effects. The compound has confirmed poor oral bioavailability, making the most commercially accessible format the least pharmacokinetically validated. The ERRalpha-null paradox (mice without ERRalpha have reduced fat mass and obesity resistance) introduces genuine complexity into interpreting ERRalpha agonism as straightforwardly beneficial. ERRgamma binding mechanistic confirmation via limited proteolysis assay was not achieved, leaving the full binding profile incompletely characterized. All animal study dosing used intraperitoneal injection at 50 mg/kg twice daily - a dose and route with no validated human equivalent. The University of Florida research team has publicly stated that additional animal safety work is required before human trials can proceed.

Is SLU-PP-332 Legal? Regulatory & Sports Status

FDA status: SLU-PP-332 is not approved by the FDA for any human use indication. It is not available through licensed compounding pharmacies for human administration. As of May 2026, no Investigational New Drug (IND) application for SLU-PP-332 has been publicly registered.

Research classification: SLU-PP-332 is classified as a research compound in all jurisdictions with relevant regulatory frameworks. It is produced and sold under research chemical designation, not as a pharmaceutical, dietary supplement, or regulated human-use compound.

WADA / USADA status: SLU-PP-332 is not currently listed by name on the World Anti-Doping Agency (WADA) prohibited list as of July 2026. However, this does not mean it is freely permitted in competitive sport. WADA's prohibited list includes a broad category covering metabolic modulators - including AMPK agonists, PPARdelta agonists, and compounds that affect cellular energy expenditure or oxygen utilization. Whether SLU-PP-332's ERR agonism falls under this category as currently written is a question for legal and anti-doping authorities, not a settled determination. The 2026 detection study was explicitly developed to support anti-doping testing for SLU-PP-332, indicating formal listing and testing protocols are being developed in parallel with the research.

Country-specific notes: No jurisdiction has specifically approved SLU-PP-332 for human use. Regulatory classification varies by country and may change as the compound gains visibility. Users outside the United States should verify the specific classification in their jurisdiction.

Detection: A validated detection methodology using LC-HRMS/MS was published in 2026, with nine specific metabolites identified as detection markers in human liver metabolism models. Whether this methodology has been implemented in active sports testing programs as of July 2026 is not confirmed in available public sources, but the infrastructure for testing is being built.

SLU-PP-332 vs. Alternatives

Commonly Paired With - Research Context Stacks

• SLU-PP-332 + BAM15: BAM15 is a mitochondrial uncoupler that increases energy expenditure by reducing the efficiency of ATP production, causing cells to burn more calories to generate the same amount of energy. The combination targets metabolic enhancement through two distinct mechanisms: ERR-pathway activation of fat oxidation and mitochondrial biogenesis (SLU-PP-332) alongside direct mitochondrial uncoupling (BAM15). A commercial combination capsule product exists, though no peer-reviewed research on this specific combination has been published.
• SLU-PP-332 + Urolithin A: Urolithin A is a gut-derived mitophagy activator - it promotes the clearance of damaged mitochondria and supports mitochondrial renewal. Pairing it with SLU-PP-332's mitochondrial biogenesis effects is mechanistically logical: clear old mitochondria, build new ones. One commercial product markets this combination. No peer-reviewed combination data exists.
• Stack information is provided for educational context - individualized research protocols are outside the scope of this guide.

Alternatives - When Another Compound May Be Considered

Cardarine (GW501516) Cardarine is a PPARdelta agonist that activates a partially overlapping set of metabolic pathways - fatty acid oxidation, oxidative fiber formation, and endurance enhancement - through a different receptor than SLU-PP-332. Animal studies produced comparable endurance improvements, and Cardarine has more extensive community experience documentation. The critical distinction: Cardarine's development was halted because of carcinogenicity signals in long-term animal studies, a safety concern not documented for SLU-PP-332. Neither compound has human trial data.

AICAR AICAR is an AMPK activator (AMPK stands for AMP-activated protein kinase, an enzyme that acts as a cellular energy sensor) that produces exercise-mimetic effects through a different upstream pathway than SLU-PP-332's ERR targeting. It has a longer research history, more published studies, and has been used in some human research contexts. Its mechanism is distinct - AMPK activation versus ERR activation - meaning the downstream effects overlap but are not identical. AICAR is better characterized pharmacokinetically but has its own set of limitations for human application.

SR9009 (REV-ERB Agonist) SR9009 activates REV-ERB receptors, which are circadian clock regulators that also influence mitochondrial function and fat metabolism. Community interest in SR9009 overlaps with SLU-PP-332 for endurance and metabolic applications. Like SLU-PP-332, its evidence base is entirely preclinical.

Comparison table:

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FAQs

What is SLU-PP-332?

SLU-PP-332 is a synthetic small molecule developed at Saint Louis University and the University of Florida that activates all three estrogen-related receptor (ERR) isoforms: ERRalpha, ERRbeta, and ERRgamma. It is classified as a pan-ERR agonist and exercise mimetic - a compound that reproduces the cellular and metabolic adaptations of aerobic exercise through molecular signaling rather than physical activity. It is not a peptide by biochemical definition, though it is grouped with peptide therapies in wellness and research pharmacy contexts.

What does SLU-PP-332 do?

SLU-PP-332 activates ERR receptors, triggering gene expression changes that mirror endurance exercise training at the cellular level - increased mitochondrial biogenesis, a shift toward fat as the primary fuel source, and enhanced oxidative muscle fiber formation. In mouse studies, these effects translated to meaningful fat loss without dietary restriction, dramatic endurance improvements, and cardioprotective effects in a heart failure model. No human outcomes data exists.

How long does SLU-PP-332 take to work?

In cell studies, the compound induces exercise-related gene expression changes within 2 hours. In mouse models, measurable metabolic and endurance changes were observed after 12 to 28 days of treatment. In human community use, reported timelines for fat loss effects cluster around weeks 4-8, with anecdotal energy or endurance changes sometimes noted earlier - though these human timelines are based on community reports, not controlled research.

What is the typical dose of SLU-PP-332?

No established human dosing protocol exists. Animal studies used 50 mg/kg intraperitoneal injection twice daily - a dose and route that cannot be directly translated to humans. Community and commercial wellness sources cite a range of approximately 200 mcg to 1.5 mg per day in various formats, with 4-8 week cycle patterns commonly described. These community figures are entirely extrapolated and unvalidated in any clinical setting.

Is SLU-PP-332 legal?

SLU-PP-332 is not approved for human use in any jurisdiction and is sold as a research compound. It is not currently named on the WADA prohibited list as of July 2026, though it may fall under the broad metabolic modulator category depending on how the list is interpreted, and anti-doping detection research for the compound was published in 2026. Users are responsible for understanding the regulatory status in their specific jurisdiction.

Can SLU-PP-332 be taken orally?

Oral capsule and powder forms are commercially available and widely used in community settings, but peer-reviewed research has confirmed that SLU-PP-332 has poor oral bioavailability - meaning a substantial portion of an orally administered dose may be metabolized before reaching systemic circulation. All published efficacy research used intraperitoneal injection in mice. Researchers at Saint Louis University developed a successor compound, SLU-PP-915, specifically to address this oral bioavailability limitation.

Is SLU-PP-332 actually a peptide?

No. SLU-PP-332 is not a peptide by any biochemical definition. It has no amino acid sequence and is a non-peptidic hydrazide small molecule with the molecular formula C18H14N2O2. It is grouped alongside peptide therapies in wellness and research pharmacy contexts because it targets overlapping research interests - metabolic health, fat oxidation, endurance - but the pharmacokinetics and mechanism that apply to peptides do not straightforwardly apply here.

How does SLU-PP-332 differ from Cardarine?

Both compounds are exercise mimetics studied for fat oxidation and endurance enhancement, but they work through completely different receptors. SLU-PP-332 activates ERR receptors (ERRalpha, ERRbeta, ERRgamma), while Cardarine activates PPARdelta. The downstream effects overlap - both drive fatty acid oxidation and oxidative muscle fiber formation - but the upstream signaling is distinct. Cardarine's development was halted due to carcinogenicity signals in long-term animal studies; no equivalent carcinogenicity concern has been documented for SLU-PP-332, though the long-term animal studies needed for a meaningful safety comparison have not been conducted.

Has SLU-PP-332 been tested in humans?

No. As of May 2026, SLU-PP-332 has not been tested in any human clinical trial, and no Investigational New Drug application has been publicly registered. All evidence comes from mouse models and cell culture experiments. The University of Florida research team has publicly stated that further animal safety testing is needed before human trials can be designed.

What is SLU-PP-915 and how does it relate to SLU-PP-332?

SLU-PP-915 is an orally bioavailable pan-ERR agonist analog developed by the same research team to address SLU-PP-332's poor oral bioavailability. It targets the same ERR pathway through the same general mechanism but with improved pharmacokinetics for practical administration. SLU-PP-915 is also preclinical; no human data exists for it either, but its development signals that the research team views oral delivery as essential for clinical translation.

Final Thoughts on SLU-PP-332

SLU-PP-332 occupies a genuinely unusual position in the exercise-mimetic and research compound landscape. The preclinical evidence is not marginal - it is robust, replicated across independent research groups, and mechanistically coherent. A compound that produces 70% improvements in endurance, 12% body weight reduction in obese mice without dietary restriction, reversal of established fatty liver disease, and cardioprotective effects in a heart failure model has earned serious scientific attention. The ERR pathway is real, the gene program activation has been confirmed at the receptor level, and the 2026 metabolism study in human liver tissue suggests the biology is not entirely foreign to human biochemistry. For researchers interested in metabolic disease, exercise physiology, heart failure, or sarcopenia, SLU-PP-332 represents a genuinely interesting line of investigation.

The caution is not rhetorical. The gap between compelling mouse data and validated human application is the central challenge of translational medicine, and SLU-PP-332 has not cleared it. No human safety data exists. No human pharmacokinetic data exists. The oral route most accessible commercially has confirmed bioavailability limitations. The research team that developed the compound has publicly stated that additional animal work is needed before human trials can begin. The ERRalpha-null paradox, the incomplete mechanistic characterization of ERRgamma binding, and the 28-day maximum study duration in any animal model are real gaps that require filling before the human application question can be answered responsibly. Anyone researching this compound should weigh these limitations alongside the striking preclinical results.

If you are researching SLU-PP-332 for its potential applications or trying to understand where it fits relative to other compounds in this category, MyPeptidePal brings together the published science, community protocol data, and compound comparison tools in one place. The Research section above summarizes what the peer-reviewed literature actually shows. The app builds on that foundation with context about how compounds like SLU-PP-332 fit within broader protocol frameworks - and it is honest about where the evidence ends and extrapolation begins.

References

1. Billon, C., et al. (2024). A synthetic ERR agonist alleviates metabolic syndrome. Journal of Pharmacology and Experimental Therapeutics.

2. Okda, H. E., et al. (2026). Chemical optimization of the exercise mimetic SLU-PP-332 enables insight into estrogen-related receptor signaling. International Journal of Biological Macromolecules, 355, 151450.

3. Billon, C., et al. (2023). Synthetic ERRα/β/γ agonist induces an ERRα-dependent acute aerobic exercise response and enhances exercise capacity. ACS Chemical Biology, 18(4), 756-771.

4. Möller, T., et al. (2026). In vitro metabolism and analytical characterization of SLU-PP-332 and SLU-PP-915: novel pan-ERR agonists with doping potential. Rapid Communications in Mass Spectrometry.

5. Bonanni, R., et al. (2025). Targeting ERRs to counteract age-related muscle atrophy associated with physical inactivity: a pilot study. Frontiers in Physiology, 16, 1616693.