Bithionol

Bithionol is an anthelmintic agent.¹ It is also an antagonist of N-acyl-phosphatidylethanolamine-hydrolyzing phospholipase D (NAPE-PLD; IC₅₀ = 2.1 µM).² Bithionol is selective for NAPE-PLD over lipoprotein lipase (LPL) and carbonic anhydrase (CA; IC₅₀s = 46 and 178 µM, respectively). It inhibits efferocytosis in primary mouse bone marrow-derived macrophages (BMDMs) when used at a concentration of 10 µM.³ Bithionol inhibits TNF-α-induced NF-κB transcriptional activity in a reporter assay using HEK293 cells (IC₅₀ = 11.2 µM).⁴ It inhibits caspase-3 activity by 90% in a cell-free assay when used at a concentration of 33 µM and prevents diphtheria toxin-, cholera toxin-, or P. aeruginosa exotoxin A-induced death in RAW 264.7 macrophages at the same concentration.⁵ Bithionol inhibits the replication of Zika virus in primary human astrocytes and Vero E6 cells (EC₅₀s = 5.5 and 6.3 µM, respectively).⁵ It decreases the number of G. salaris helminths in G. salaris-infected O. mykiss without inducing toxicity when used at concentrations of 12.5 or 20 mg/L.¹ Formulations containing bithionol have previously been used in soaps and cosmetics.

WARNING This product is not for human or veterinary use.

1. Santamarina, M.T., Tojo, J., Ubeira, F.M., et al. Anthelmintic treatment against Gyrodactylus sp. infecting rainbow trout Oncorhynchus mykiss. Dis. Aquat. Org. 10(1), 39-43 (1991).

2. Aggarwal, G., Zarrow, J.E., Mashhadi, Z., et al. Symmetrically substituted dichlorophenes inhibit N-acyl-phosphatidylethanolamine phospholipase D. The Journal of Biological Chemisty 295(21), 7289-7300 (2020).

3. Zarrow, J.E., Alli-Oluwafuyi, A.M., Youwakim, C.M., et al. Small Molecule Activation of NAPE-PLD Enhances Efferocytosis by Macrophages. ACS Chem. Biol. 18(8), 1891-1904 (2023).

4. Miller, S.C., Huang, R., Sakamuru, S., et al. Identification of known drugs that act as inhibitors of NF-κB signaling and their mechanism of action. Biochem. Pharmacol. 79(9), 1272-1280 (2016).

5. Leonardi, W., Zilbermintz, L., Cheng, L.W., et al. Bithionol blocks pathogenicity of bacterial toxins, ricin, and Zika virus. Sci. Rep. 6:34475, 1-12 (2016).