βOHB also increases acetylation of proteins being a potent inhibitor of histone deacetylases [203]; this action can lead to beneficial effects in HF due to the activation of neighboring genes such as Forkhead Box O3 (FOXO3), which confers resistance to oxidative stress and sirtuins, already known to have strong cardioprotective roles [204]. This evidence concerns the gene FOXO3 and hydrops fetalis.