Ferulic Acid Promotes Hematopoietic Stem Cell Maintenance in Homeostasis and Injury Through Diminishing Ferroptosis Susceptibility.

Redox balance is essential for maintenance of the hematopoietic stem cell (HSC) pool, which ensures the lifelong hematopoiesis. However, oxidative attack induced by various physiopathological stresses always compromises HSC maintenance, while there remains lack of safe and effective antioxidative measures combating these conditions. Here, we show that ferulic acid (FA), a natural antioxidant abundantly present in Angelica sinensis which is a traditional Chinese herb commonly used for promotion of blood production, distinctively and directly promotes HSC maintenance and thereby boosts hematopoiesis at homeostasis, whether supplemented over the long term in vivo or in HSC culture ex vivo. Using a mouse model of acute myelosuppressive injury induced by ionizing radiation, we further reveal that FA supplementation effectively safeguards HSC maintenance and accelerates hematopoietic regeneration after acute myelosuppressive injury. Mechanistically, FA diminishes ferroptosis susceptibility of HSCs through limiting the labile iron pool (LIP), thus favoring HSC maintenance. In addition, the LIP limitation and anti-ferroptosis activity of FA is independent of nuclear-factor erythroid 2-related factor 2 (NRF2), probably relying on its iron-chelating ability. These findings not only uncover a novel pharmacological action and mechanism of FA in promoting HSC maintenance, but also provides a therapeutic rationale for using FA or FA-rich herbs to treat iron overload- and ferroptosis-associated pathologies such as acute myelosuppressive injury.