β‑Hydroxybutyrate‑Driven Lysine β‑Hydroxybutyrylation Links Energy Metabolism to Epigenetic Regulation
The review outlines how β‑hydroxybutyrate (BHB), a ketone body elevated by fasting, ketogenic nutrition, and exogenous supplements, serves as a substrate for lysine β‑hydroxybutyrylation (Kbhb). Kbhb modifies histone and non‑histone proteins, influencing chromatin accessibility and transcription, thereby connecting metabolic state to gene‑regulatory networks.
Study and findings
The authors summarize experimental evidence that BHB is not merely a fuel but also a signaling molecule. Elevated circulating BHB, achieved through medium‑chain triglyceride intake, prolonged fasting, classical ketogenic diet, or exogenous ketone esters, correlates with increased Kbhb on histone tails and on diverse cytoplasmic proteins. Enzymatically, the acetyl‑transferase family p300/CBP acts as a “writer” adding the β‑hydroxybutyryl group, while class I HDACs and SIRT deacetylases function as “erasers” removing it. Functional studies link Kbhb to enhanced expression of genes involved in oxidative metabolism, stress resistance, and anti‑inflammatory pathways. The review also notes that Kbhb can remodel protein activity beyond chromatin, affecting enzymes and signaling proteins, thereby broadening its impact on cellular physiology.
Clinical interpretation
For clinicians, the implication is that interventions raising BHB—whether dietary, fasting‑based, or supplemental—may modulate gene expression through Kbhb, potentially influencing metabolic health, inflammation, and neuroprotection. However, the evidence remains at the mechanistic level; direct clinical outcomes linked to Kbhb‑mediated transcriptional changes have not been demonstrated in patient trials. The review therefore positions BHB‑induced Kbhb as a plausible molecular conduit through which ketogenic strategies could exert systemic effects, but it does not establish therapeutic efficacy.
Limitations and open questions
The primary limitation is the reliance on pre‑clinical models and in‑vitro assays to infer human relevance. Quantitative relationships between dietary BHB concentrations, tissue‑specific Kbhb levels, and downstream phenotypic outcomes are incompletely mapped. Moreover, the identity of all non‑histone Kbhb substrates and the context‑dependent consequences of their modification remain uncertain. Future research will need controlled human studies that measure BHB, Kbhb, and functional endpoints concurrently, and that dissect the relative contributions of writer and eraser enzymes in vivo.
Source
Cheng S et al. Metabolism Meets Epigenetics: β‑Hydroxybutyrate‑Driven Lysine β‑Hydroxybutyrylation Bridging Energy Metabolism With Transcription and Protein Functional Remodeling. Nutrition Reviews. 2026; PMID: 41418322; DOI: 10.1093/nutrit/nuaf258.