BHRC BLOG
SLU-PP-332: “Exercise in a Pill” — Protocol Claims & What the Evidence Shows
BHRC · LONGEVITY & WELLNESS · EVIDENCE REVIEW
Search SLU-PP-332 and you will find dosing charts, cycle lengths, oral-versus-injectable comparisons, and a mouse that ran 70% longer. Almost all of that confidence is manufactured. The mouse is real — the research is genuinely interesting, published in good journals, and the mechanism holds up. What does not exist is a single human being who has received this compound in a published study. This guide covers what the research actually found, why the laboratory that invented it went on to build a different molecule, why the circulating dosing numbers do not add up, and what the honest alternative looks like if the goal underneath the search is real.
1 · First, it is not a peptide
Almost every vendor files SLU-PP-332 under peptides. It is not one, and the error matters because it tells you how carefully the source is reading.
SLU-PP-332 is an acylhydrazone — a small synthetic organic molecule, formula C₁₈H₁₄N₂O₂, molecular weight 290.32 g/mol. Peptides are chains of amino acids; this is not. The “SLU” is Saint Louis University, where the medicinal chemistry was done in Thomas Burris’s laboratory.
What it targets
The estrogen-related receptors — ERRα, ERRβ and ERRγ — are orphan nuclear receptors. Despite the name, they do not bind estrogen and are not estrogen receptors. They are transcription factors that sit permanently switched on and decide which metabolic genes a cell transcribes. They are most abundant where energy demand is highest: heart, skeletal muscle, liver, kidney, brown fat.
2 · The exercise-mimetic idea, explained properly
When you train endurance, a coactivator called PGC-1α rises in your muscle. On its own PGC-1α does very little — it needs a partner transcription factor to sit on DNA with. For the mitochondrial arm of the training response, that partner is ERRα.
Together they switch on three gene programs: mitochondrial biogenesis (building more mitochondria per muscle cell), oxidative phosphorylation (the electron transport chain and Krebs cycle machinery), and fatty-acid oxidation (the enzymes that import and burn fat for fuel).
SLU-PP-332 skips the exercise and turns that node on directly.
3 · What the animal studies actually found
The research record is small, consistent, and entirely preclinical. Here is what is in it.
Exercise capacity — ACS Chemical Biology, 2023
Sedentary mice were given 50 mg/kg twice daily by intraperitoneal injection for seven days, then run on a treadmill to exhaustion. Treated mice ran about 70% longer and 45% farther than vehicle controls. They showed an increase in type IIa oxidative muscle fibers, and grip strength increased over a two-week dosing arm.
The most convincing part of that paper is the control: in mice whose muscle ERRα had been genetically knocked out, SLU-PP-332 produced no endurance benefit at all. That is strong evidence the effect is genuinely ERRα-mediated rather than an artifact.
Obesity and metabolic syndrome — JPET, 2024
Mice made obese on a 60%-fat diet received 50 mg/kg twice daily by injection for 28 days.
Glucose tolerance improved in the obese mice, though the insulin tolerance test was unchanged. Total cholesterol, triglycerides and liver fat all fell. HDL cholesterol also fell — which, in a human context, is the kind of signal that would require dedicated cardiovascular safety evaluation.
Heart failure — Circulation, 2024
In a pressure-overload heart failure model, SLU-PP-332 at 25 mg/kg twice daily improved ejection fraction at weeks four through six and reduced fibrosis. Cardiac hypertrophy was not reduced. The mediating receptor in the heart turned out to be ERRγ rather than ERRα.
The human cells study people misrepresent
A 2025 Frontiers in Physiology pilot applied SLU-PP-332 to primary myoblast cultures taken from twenty elderly women undergoing hip surgery. Oxidative stress fell 37.7% and glutathione rose 117.4% in those cultures. You will see this cited as a “human study.” No human being received the drug. It was cells in a dish.
4 · The route problem, which is the whole story
Every in-vivo result above was produced by intraperitoneal injection in rodents — a needle into the abdominal cavity. It is a laboratory convenience route. Outside of specific procedures like peritoneal dialysis, it is not used in humans at all.
That has three consequences, and they are not minor.
Oral dosing is contradicted by the people who invented it
This is the cleanest fact in the whole topic. In 2025, Burris’s lab published a paper in JPET introducing a successor compound, SLU-PP-915. The abstract states directly that SLU-PP-332 lacks oral bioavailability, and that SLU-PP-915 was designed to fix precisely that.
The laboratory that made this molecule built an entirely different molecule because this one does not work by mouth. A 50 mg oral tablet of a compound with no oral absorption is not a conservative dose of an active drug — its actual systemic exposure is unknown, and may vary unpredictably between products and between people.
The dose arithmetic does not work either
Apply FDA’s standard body-surface-area conversion to the mouse dose and 50 mg/kg corresponds to roughly 4.1 mg/kg in a human — about 244 mg per dose, or roughly 488 mg a day, by injection, for a 60 kg adult. Circulating protocols of 250 mcg to 1.5 mg a day sit two to three orders of magnitude below that.
To be fair to the arithmetic: that conversion is designed for estimating safe starting doses in first-in-human trials, not for predicting efficacy, so it should not be read as a recommended human dose. What it does show is how far the circulating numbers sit from anything that has ever been studied — while being delivered by a route that has never been studied at all.
And nobody knows the half-life
No half-life has ever been published for SLU-PP-332, in any species. Not in the ACS paper, not in JPET, not in Circulation. The entire public pharmacokinetic dataset is two timepoints: two hours after a 30 mg/kg injection, concentrations were about 0.6 µM in skeletal muscle and 0.2 µM in plasma. There is no human ADME data, no metabolite profile, no protein binding, no drug-interaction data.
5 · Where it stands legally, and why absence is not approval
- Not FDA-approved for any indication, in any species
- Not on the 503A bulk substances list, and not in any of the interim policy categories — so no compounding pharmacy has a lawful pathway to it
- Not a legal dietary supplement ingredient
- Sold as a research chemical, labeled not for human consumption, with no verified identity, purity, potency, sterility or endotoxin testing
- No human clinical trials — no published Phase 1, no announced IND
It is worth being precise about what that fourth bullet means. Absence from FDA’s safety-risk list is not a safety endorsement — it means FDA has never evaluated the substance for compounding at all. And the University of Florida’s own 2023 announcement described the compound as being in early development, with next steps including testing for side effects in more animal models before any jump to human trials.
6 · Why turning on ERRs everywhere is not trivially safe
This section exists because most content on this compound skips it entirely.
The cancer question
ERRα’s best-characterized pathological role is in cancer. A 2023 review in the International Journal of Molecular Sciences summarizes that high ERRα expression correlates with poor prognosis in breast, ovarian, prostate and colon cancer, and that in malignant cells ERRα drives proliferation, metabolic adaptation, hypoxia resistance, angiogenesis and invasion.
A systemic pan-ERR agonist pushes on that same node. No carcinogenicity, genotoxicity or tumor-promotion studies of SLU-PP-332 have been published. This is not speculative hand-waving — it is the receptor’s most studied role in disease, and it has not been investigated for this compound.
Two further points worth knowing. First, ERRs are constitutively active — permanently switched on without a ligand — so the intervention amplifies an already-running transcription factor across every tissue that expresses it. Nobody knows what that does over a lifetime of tissue turnover. Second, the cardiac data cuts both ways: ERRγ agonism improved failing mouse hearts, but nothing establishes what chronic ERRγ agonism does to a healthy human one.
7 · What to do if the underlying goal is real
None of this is a reason to be uninterested in metabolic health. It is a reason to be uninterested in this specific molecule, right now. The goal underneath the search — burn more fat, build endurance, get metabolic markers moving — is a legitimate one with options that have human evidence behind them.
Physician-supervised metabolic, weight management and peptide programs are available at all six BHRC studios. Consultations are free, include a review of your history and labs, and carry no obligation.
We will tell you plainly what the evidence supports — including when the honest answer is “not yet.”
Frequently Asked Questions
Is SLU-PP-332 a peptide?
No. It is a small synthetic molecule — an acylhydrazone, formula C₁₈H₁₄N₂O₂, molecular weight 290.32. Peptides are chains of amino acids; this is not one. Vendors routinely file it under peptides, which is chemically wrong.
Are there human studies?
No. Every published in-vivo study is in mice. A 2025 Frontiers in Physiology paper applied the compound to human muscle cells in culture, which is sometimes cited as a human study — no person received the drug. There is no published Phase 1, no registered trial and no announced IND.
Is it FDA-approved?
No, for any indication in any species. It is also not on the 503A bulk substances list or in any interim policy category, which means no compounding pharmacy has a lawful pathway to it. Absence from FDA’s safety-risk list is not an endorsement — it means FDA has never evaluated it.
What is the human dose?
There isn’t one. No human dose-finding study exists, so any number presented as a protocol is not derived from anything. The circulating figures — 250 mcg to 1.5 mg a day, or 50 mg oral tablets — sit two to three orders of magnitude below the body-surface-area equivalent of the studied mouse dose, while being delivered by routes that have never been studied.
Does the oral version work?
The laboratory that invented the compound published a 2025 paper stating plainly that SLU-PP-332 lacks oral bioavailability, and introducing a different molecule, SLU-PP-915, designed to solve that problem. That is the strongest available evidence on the question, and it comes from the inventors.
What did the mouse studies actually show?
Treated mice ran about 70% longer and 45% farther. Obese mice gained roughly ten times less fat than controls without eating less or moving more, with fatty-acid oxidation up 25%. In a heart failure model, ejection fraction improved and fibrosis fell, though hypertrophy did not. All by intraperitoneal injection.
What are the safety risks?
Largely unquantified. The published toxicology is ten days of blood counts, electrolytes and creatine kinase in mice. There is no carcinogenicity, genotoxicity, reproductive, immunotoxicology or neurobehavioral data. The specific concern is that ERRα’s best-characterized disease role is in cancer — high expression correlates with poor prognosis in several tumor types — and a systemic agonist pushes on that node.
Is it detectable in drug testing?
Two 2026 analytical papers describe metabolite characterization of SLU-PP-332 and its successor explicitly for doping-control purposes. Tested athletes should assume detection methods are being deployed and should check the current prohibited list directly.
What is a better-evidenced alternative?
Start with measurement. Advanced diagnostic testing tells you which metabolic, inflammatory or hormonal markers are actually out of range for you. Medical weight management has large, replicated human trial evidence, and targeted peptides with clearer regulatory standing can follow where indicated — under supervision, with follow-up labs.
Will you prescribe it?
No. There is no lawful compounding pathway for SLU-PP-332 and no human safety data to prescribe against. If your goal is endurance, fat loss or metabolic health, book a consultation and we will work on the version of that problem where the evidence actually exists.
Keep Reading
- SLU-PP-332 at BHRC
- 5-Amino-1MQ Dosage Guide: Oral Protocol, Cycling & Fat-Loss Research
- MOTS-c Peptide: How It Works, Benefits & Dosage Protocol
- Cagrilintide + CagriSema: Titration, Trial Data & How It Works
- Medical Weight Management at BHRC
- Advanced Diagnostic Testing
- Longevity & Healthspan at BHRC
- FDA Peptide Reclassification 2026 — What It Means for Patients
Metabolic & Peptide Programs at a BHRC Studio Near You
Physician-supervised metabolic, weight management and peptide programs are available at BHRC studios nationwide, including our main six. Tap your closest location to book a free consultation:
Westlake VillageConejo Valley, CA
West HollywoodLos Angeles, CA
West Los AngelesLos Angeles, CA
SummerlinLas Vegas, NV
Paradise ValleyScottsdale / Phoenix, AZ
References & Further Reading
- University of Florida News — Exercise-mimicking drug sheds weight, boosts muscle activity in mice, 2023. news.ufl.edu
- ACS Chemical Biology (institutional record) — Billon C et al. Synthetic ERRα/β/γ Agonist Induces an ERRα-Dependent Acute Aerobic Exercise Response and Enhances Exercise Capacity, 2023. collections.uhsp.edu
- Journal of Pharmacology and Experimental Therapeutics (institutional record) — Billon C et al. A Synthetic ERR Agonist Alleviates Metabolic Syndrome, 2024. scholars.uhsp.edu
- Circulation (institutional record) — Xu W et al. Novel Pan-ERR Agonists Ameliorate Heart Failure Through Enhancing Cardiac Fatty Acid Metabolism and Mitochondrial Function, 2024. scholars.uhsp.edu
- Journal of Pharmacology and Experimental Therapeutics (institutional record) — Billon C et al. An orally active ERR agonist, SLU-PP-915, enhances aerobic exercise capacity, 2025 — states SLU-PP-332 lacks oral bioavailability. scholars.uhsp.edu
- International Journal of Molecular Sciences — Cerutti C, Shi J-R, Vanacker J-M. Multifaceted Transcriptional Network of Estrogen-Related Receptor Alpha in Health and Disease, 2023. mdpi.com
- Frontiers in Physiology — Targeting ERRs to counteract age-related muscle atrophy associated with physical inactivity: a pilot study (human cells in culture), 2025. frontiersin.org
- bioRxiv (preprint of American Journal of Pathology 2023) — Estrogen-related receptor agonism reverses mitochondrial dysfunction and inflammation in the aging kidney. biorxiv.org
- U.S. Food & Drug Administration — Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act. fda.gov
- U.S. Food & Drug Administration — Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. fda.gov
- U.S. Food & Drug Administration / CDER — Guidance for Industry: Estimating the Maximum Safe Starting Dose in Initial Clinical Trials for Therapeutics in Adult Healthy Volunteers, 2005. fda.gov
- Technology Networks — Exercise-Mimicking Drug Helps Mice Lose Weight and Boost Endurance, 2023. technologynetworks.com
Beverly Hills Rejuvenation Center. This content is for general education and does not create a physician-patient relationship or constitute medical advice. SLU-PP-332 is not approved by the FDA for any use, has not been studied in humans, and is not prescribed or provided by BHRC. Nothing in this article is a dosing recommendation. Figures cited are from animal and cell-culture studies and do not predict effects in people. Candidacy, dosing, results and pricing vary by person and are confirmed at a free consultation. Reviewed by the BHRC clinical team.
