Butanoic acid is an endogenous human metabolite, an endogenous histone deacetylase (HDAC) inhibitor. The IC50 of HDAC3, HDAC4 and HDAC1 were 2.4 mM, 4.5 mM and 5.3 mM, respectively. 3-Hydroxybutyric acid has the effects of energy metabolism, neuroprotection, anti-inflammatory, and improvement of insulin resistance.

HDAC4:4.5 mM, HDAC3:2.4 mM, HDAC1:5.3 mM

METHODS: After HEK293 cells were treated with 3-Hydroxybutyric acid (10 mM) for 24 hours, the acetylation levels of histone H3K9 on the _Foxo3a_ and _Mt2_ promoters were detected.
RESULTS: 3-Hydroxybutyric acid increases the acetylation of histone H3K9 in HEK293 cells on the _Foxo3a_ and _Mt2_ promoters. [1]
METHODS: Mouse glial cells were treated with 3-Hydroxybutyric acid (10 mM) for 48 hours, and the cell proliferation was detected by the MTT assay.
RESULTS: 3-Hydroxybutyric acid significantly promotes cell proliferation. [2]
METHODS: Human monocytes were treated with 3-Hydroxybutyric acid (1-20 mM) for 24 hours, and the protein levels were detected by Western Blot.
RESULTS: 3-Hydroxybutyric acid dose-dependently inhibits the production of IL-1β and IL-18 mediated by the NLRP3 inflammasome. [3]

METHODS: To study the neuroprotective effect of 3-Hydroxybutyric acid, 3-Hydroxybutyric acid (2 mM or 5 mM) was injected intraventricular into C57BL/6 mice.
RESULTS: 3-Hydroxybutyric acid reduces the binding of HDAC2 and HDAC3 to the pI promoter of _Bdnf_. [4]
METHODS: To study the neuroprotective effect of 3-Hydroxybutyric acid, 3-Hydroxybutyric acid (5.0 mmol/kg) was intraperitoneally injected into neonatal mice after hypoxia-ischemia treatment.
RESULTS: 3-Hydroxybutyric acid reduces the number of Tunel-positive cells in brain regions, reduces cerebral infarction, and thereby alleviates brain injury. [5]