Characterization of recombinant human liver dehydroepiandrosterone sulfotransferase with minoxidil as the substrate

Patrick E. Kudlacek, Dahn L. Clemens, Christine M. Halgard, Robert J. Anderson

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


Biotransformation of xenobiotics and hormones through sulfate conjugation is an important metabolic pathway in humans. The activation of minoxidil, an antihypertensive agent and hair growth stimulator, by sulfation (sulfonation) is carried out by more than one sulfotransferase. Initially only the thermostable form of phenol sulfotransferase was thought to catalyze minoxidil sulfation. We document in this report the new finding that human liver dehydroepiandrosterone sulfotransferase (DHEA ST), an hydroxysteroid sulfotransferase distinct from phenol sulfotransferases, also catalyzes the reaction. To characterize more precisely the activity of DHEA ST toward minoxidil, we used COS-1 cells to express DHEA ST from a human liver cDNA clone. The apparent K(m) values for minoxidil and [35S]3'-phosphoadenosine-5'-phosphosulfate were 3.9 mM and 0.13 μM, respectively. The 50% inactivation temperature of the COS-expressed enzyme was 42°, and the IC50 value for 2,6-dichloro-4-nitrophenol was 1.4 x 10-4M. Both the thermal stability behavior and response to DCNP were similar when the cDNA encoded DHEA ST was assayed with DHEA or minoxidil as a substrate. NaCl led to a greater activation of the cDNA-expressed DHEA ST when assayed with DHEA (2.5-fold) than when the same preparation was assayed with minoxidil (1.4-fold). These data indicate that DHEA ST catalyzes the sulfate conjugation of minoxidil. DHEA ST activity present in the human gut and liver would be expected to add to the overall sulfate conjugation of orally administered minoxidil. Thus, DHEA ST activity must be considered when determining the human tissue sulfotransferase contribution to minoxidil sulfation.

Original languageEnglish (US)
Pages (from-to)215-221
Number of pages7
JournalBiochemical Pharmacology
Issue number2
StatePublished - Jan 24 1997

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Pharmacology


Dive into the research topics of 'Characterization of recombinant human liver dehydroepiandrosterone sulfotransferase with minoxidil as the substrate'. Together they form a unique fingerprint.

Cite this