IF a novel small molecule allosteric activator — identified via structure-based virtual screening against the cryptic hydrophobic/charged interface pocket of the GLO1 homodimer (UniProt Q04760) modeled using AF-Q04760-F1, targeting a site distal to the dual Zn²⁺ active centers and computationally predicted to stabilize the catalytically favorable asymmetric conformational state observed upon phosphorylation — is administered systemically (i.p. or oral gavage, dose to be optimized in Phase 1, estimated 10–50 mg/kg/day based on analogous dimeric enzyme modulators) to 20-month-old C57BL/6J male and female mice (late-stage accumulation model),

THEN a measurable reduction in tissue methylglyoxal (MG) concentration (≥30% decrease in kidney, brain, and aorta by LC-MS/MS), a corresponding decrease in MG-derived advanced glycation endproduct (AGE) adducts — specifically Nε-(carboxyethyl)lysine (CEL) and Nδ-(5-hydro-5-methyl-4-imidazolinone-2-yl)-ornithine (MG-H1) — measured by competitive ELISA and immunohistochemistry, alongside improved GLO1 Vmax/kcat in tissue lysates (≥1.5-fold over vehicle), will be observed within 8 weeks of treatment,

BECAUSE the following causal chain links allosteric activation to metabolic damage repair:

1. Methylglyoxal accumulates as genuine cytotoxic damage in aged tissues: MG is a highly reactive dicarbonyl byproduct of glycolysis that forms covalent protein and nucleic acid adducts (AGEs); circulating and intracellular MG pools rise with age, and the accumulated hemithioacetal intermediate (MG-glutathione conjugate) represents a chemically reversible "damage reservoir" that GLO1 can directly convert to D-lactate — constituting true repair of accumulated reactive metabolite load [Research Context, Q04760 framing].

2. GLO1 homodimer exhibits phosphorylation-induced dynamic asymmetry that primes one active site for enhanced catalysis: MD simulation studies cited in the Research Context indicate that phosphorylation at known GLO1 phosphosites induces conformational heterogeneity between the two subunits of the homodimer, creating a dominant-active protomer — meaning the enzyme has latent catalytic capacity that is not fully utilized in basal, unphosphorylated, aged-tissue conditions where kinase signaling is impaired [Research Context, MD simulation findings].

3. A cryptic allosteric pocket exists at the dimer interface distal to the active site: AlphaFold model AF-Q04760-F1, combined with pocket-detection algorithms (FPocket, SiteMap, CryptoSite referenced in Research Context), predicts hydrophobic and charged interdomain regions at the homodimer interface that are not occupied by substrate or the Zn²⁺ cofactor, and that communicate conformationally with the active site — a validated topology for allosteric activation in homodimeric metalloenzymes [Research Context, computational framing].

4. Small molecule occupancy of this interface pocket can functionally mimic phosphorylation-induced asymmetry [SPEC...

SENS category: GlycoSENS

Key references: • doi.org/10.1101/2025.05.02.651384].