Butyric acid-d7 is intended for use as an internal standard for the quantification of sodium butyrate by GC- or LC-MS. Butyric acid is a short-chain fatty acid.[1] It is produced predominately by bacterial fermentation of dietary fiber in the colon but has also been identified in mammalian milk.[1],[2] Butyric acid is an inhibitor of histone deacetylase (HDAC; IC50 = 90 μM in a cell-free assay).[3] It induces differentiation, cell cycle arrest at the G0 phase, and apoptosis, as well as inhibits proliferation, in a variety of cancer cells when used at concentrations ranging from 0.6 to 100 mM.[2],[5],[6] Butyric acid decreases the expression of IFN-γ-related signaling genes and metastatic genes in H460 human lung cancer cells when used at a concentration of 2 mM.[5] It reduces tumor growth in a CaSki mouse xenograft model when administered at doses of 200 and 800 mg/kg per day.[4] Butyric acid also reduces increases in colonic TNFa and Il6 expression and decreases colonic goblet cell depletion, tissue damage, muscle thickening, and cellular infiltration in a wild-type, but not Hcar2-/-, mouse model of TNBS-induced colitis.[7]

Reference:
[1]. Wang, M., Wichienchot, S., He, X., et al. In vitro colonic fermentation of dietary fibers: Fermentation rate, short-chain fatty acid production and changes in microbiota. Trends Food Sci. Technol. 88(1), 1-9 (2019).
[2]. Smith, J.G., Yokoyama, W.H., and German, J.B. Butyric acid from the diet: Actions at the level of gene expression. Crit. Rev. Food Sci. Nutr. 38(4), 259-297 (1998).
[3]. Waldecker, M., Kautenburger, T., Daumann, H., et al. Inhibition of histone-deacetylase activity by short-chain fatty acids and some polyphenol metabolites formed in the colon. J. Nutr. Biochem. 19(9), 587-593 (2008).
[4]. Decrion-Barthod, A.-Z., Bosset, M., Plissonnier, M.-L., et al. Sodium butyrate with UCN-01 has marked antitumour activity against cervical cancer cells. Anticancer Res. 30(10), 4049-4061 (2010).
[5]. Joseph, J., Mudduluru, G., Antony, S., et al. Expression profiling of sodium butyrate (NaB)-treated cells: identification of regulation of genes related to cytokine signaling and cancer metastasis by NaB. Oncogene 23(37), 6304-6315 (2004).
[6]. Chabanas, A., Khoury, E., Goeltz, P., et al. Effects of butyric acid on cell cycle regulation and induction of histone Hl° in mouse cells and tissue culture inducibility of Hl° in the late S-G2 phase of the cell cycle. J. Mol. Biol. 183(2), 141-151 (1985).|7. Chen, G., Ran, X., Li, B., et al. Sodium butyrate inhibits inflammation and maintains epithelium barrier integrity in a TNBS-induced inflammatory bowel disease mice model. EBioMedicine 30(1), 317-325 (2018).