Selective inhibition of monoamine oxidase A by purpurin, an anthraquinone

作者：Lee Hyun Woo; Ryu Hyung Won; Kang Myung Gyun; Park Daeui; Oh Sei Ryang; Kim Hoon^*

来源：Bioorganic & Medicinal Chemistry Letters, 2017, 27(5): 1136-1140.

DOI：10.1016/j.bmcl.2017.01.085

• Purpurin
• Monoamine oxidase A
• Selective inhibitor
• Competitive inhibitor
• Molecular docking

Monoamine oxidase (MAO) catalyzes the oxidation of monoamines that act as neurotransmitters. During a target-based screening of natural products using two isoforms of recombinant human MAO-A and MAO-B, purpurin (an anthraquinone derivative) was found to potently and selectively inhibit MAO-A, with an IC50 value of 2.50 mu M, and not to inhibit MAO-B. Alizarin (also an anthraquinone) inhibited MAO-A less potently with an IC50 value of 30.1 mu M. Furthermore, purpurin was a reversible and competitive inhibitor of MAO-A with a K-i value of 0.422 mu M. A comparison of their chemical structures suggested the 4-hydroxy group of purpurin might play an important role in its inhibition of MAO-A. Molecular docking simulation showed that the binding affinity of purpurin for MAO-A (-40.0 kcal/mol) was higher than its affinity for MAO-B (-33.9 kcal/mol), and that Ile 207 and Gly 443 of MAO-A were key residues for hydrogen bonding with purpurin. The findings of this study suggest purpurin is a potent, selective, reversible inhibitor of MAO-A, and that it be considered a new potential lead compound for development of novel reversible inhibitors of MAO-A (RIMA5).

• 出版日期2017-3-1