The history context and future directions of lactic acid

Lactic acid, initially considered a neglected metabolic waste product, has gradually shown its irreplaceable value in the human body. Up to now, it has become a hot topic of current research. From its first time its discovery in milk to its becoming a product of cellular respiration and metabolism, lactic acid was viewed to be a useless product in metabolism and therefore resulted in the suspension of related research. Later, with the birth of the concept of lactate shuttle between cells, lactate once again showed a very important function in the energy field of physiological research, including the participation of whole-body energy metabolism and the regulation of the cancer microenvironment. However, after some time, the research on lactic acid seems to have stalled again in the role of lactic acid as a small molecule. Not until 2019, the discovery of acetylation of histone extended a new field of lactate research epigenetic modification. This review summarizes the research on various aspects of lactate and highlights the progress and application of lactate in histone modification.