Lactate as a major epigenetic carbon source for histone acetylation via nuclear LDH metabolism
Histone acetylation involves the transfer of a two-carbon unit to nucleus as embedded in low-concentration metabolites. We find that lactate, a high-concentration metabolic by-product, can be a major carbon source for histone acetylation, through oxidation-dependent metabolism. Both in cells and in purified nucleus, 13C3-lactate carbons are incorporated into histone H4 (maximum incorporation: ~60%). In purified nucleus, this process depends on nucleus-localized lactate dehydrogenase (LDHA), the knockout of which abrogates the incorporation. Heterologous expression of nucleus-localized LDHA rescues the KO effect. Lactate itself increases histone acetylation, whereas inhibition of LDHA reduces the acetylation. In vitro and in vivo settings exhibit different lactate incorporation patterns, suggesting an influence of the microenvironment. Higher nuclear LDHA localization is observed in pancreatic cancer than in normal tissues, showing the disease relevance. Overall, lactate and nuclear LDHA can be major structural and regulatory players in the metabolism-epigenetics axis controlled by cell's own or environmental status. Overall design: Differences in ChIP peaks of histone acetyl H4 on chromosomes following 0 or 10 mM lactate treatment in PANC-1 cell