SLU-PP-332

SLU-PP-332 is a synthetic small molecule designed as a pan-agonist of all three ERR isoforms (α, β, γ). Unlike previous selective ERR ligands, SLU-PP-332's broad-receptor activation is what produces its distinctive exercise-like transcriptomic profile.

SLU-PP-332 emerged from the laboratory of Thomas Burris (Saint Louis University, then Scripps Florida and University of Florida), where the group has been characterizing the estrogen-related receptors (ERRα, ERRβ, ERRγ) as nuclear-receptor regulators of mitochondrial biogenesis and energy metabolism. ERRs are "orphan" nuclear receptors with no known endogenous ligand, but they share extensive transcriptional networks with PGC-1α — the master coactivator of exercise-induced mitochondrial adaptation.

The compound came to broader attention with a 2023 publication (followed by a 2024 Molecular Metabolism paper) showing SLU-PP-332 dosed daily in mice produced increased running endurance, weight loss without reduced food intake, improved insulin sensitivity, and skeletal-muscle gene-expression patterns matching those seen with exercise. The framing as an "exercise mimetic" generated significant interest in research-chemical and biohacker communities.

ERRs drive expression of genes involved in mitochondrial biogenesis, fatty acid oxidation, and oxidative phosphorylation — the same pathways activated by exercise via the PGC-1α coactivator. Direct ERR agonism by SLU-PP-332 is positioned as a way to drive these adaptations without the muscle contraction and metabolic stress that exercise itself requires.^[1]

Mechanistically interesting parallels exist with previous exercise-mimetic candidates — AICAR (AMPK activator) and the now-banned GW501516 (PPARδ agonist) — both of which produced striking preclinical results that did not translate cleanly to safe human use. The ERR pathway has a different molecular identity from those programs, but the translational risk pattern is worth keeping in mind.

Pharmacokinetic data for SLU-PP-332 in humans is not published. Preclinical mouse work has used daily intraperitoneal dosing in the milligram-per-kilogram range. Oral bioavailability appears to be acceptable in animal studies but has not been characterized in humans.

The peer-reviewed literature on SLU-PP-332 is summarized below across two tiers: human research (the highest standard), and preclinical / emerging research (animal models and early-stage human work).

This table summarizes commonly discussed claims and how the published evidence weighs in. The aim is clarity — supported claims, claims that look promising but need more data, and claims that outrun the science.

Animal studies have used daily intraperitoneal injection in the mg/kg range. There is no clinical protocol for human use; the compound is not a clinical pharmaceutical product.

SLU-PP-332 is one of the most exciting recent preclinical findings in metabolic / exercise-mimetic biology — the rodent data is genuinely striking, the mechanism is mechanistically novel, and the framing has captured significant attention in longevity and performance circles. The honest framing for human readers is: this is mouse data. The translational distance from "improves running capacity in mice" to "viable longevity therapeutic in humans" is the same distance that has defeated many earlier exercise-mimetic candidates. Worth tracking as a research direction; not yet supported as a clinical or self-experimentation strategy.