Lack of aquaporin-4 water transport inhibition by antiepileptics and arylsulfonamides.

Abstract

Inhibitors of brain glial water channel aquaporin-4 (AQP4) are of potential clinical utility, as they are predicted to modulate brain edema, neuroexcitation and glial scarring. Recently, Huber et al. (Bioorg. Med. Chem.2007, 17, 1270-1273; in press) reported that a series of arylsulfonamides, antiepileptics, and related small molecules strongly inhibited AQP4 water transport with IC(50)s down to 1 microM. We retested the compounds with greatest reported potencies, including acetylsulfanilamide, acetazolamide, 6-ethoxy-benzothiazole-2-sulfonamide, topiramate, zonisamide, phenytoin, lamotrigine, and sumatriptan, in AQP4-transfected mammalian cells and primary cultures of brain glial cells, using several sensitive assays of osmotic water permeability. Contrary to the findings of Huber et al., in our studies we found no significant inhibition of AQP4 water permeability by any of the compounds at concentrations up to 100 microM.

• Authors: Baoxue Yang, Hua Zhang, A S Verkman
• Journal: Bioorganic & medicinal chemistry (Bioorg Med Chem) Vol. 16 Issue 15 Pg. 7489-93 (Aug 01 2008) ISSN: 1464-3391 [Electronic] England
• PMID: 18572411 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Anticonvulsants
• Aquaporin 4
• Sulfonamides
• Water

Topics

• Animals
• Anticonvulsants (pharmacology)
• Aquaporin 4 (metabolism)
• Biological Transport, Active (drug effects)
• Cell Line
• Mice
• Molecular Structure
• Neuroglia (metabolism)
• Permeability
• Rats
• Structure-Activity Relationship
• Sulfonamides (pharmacology)
• Thyroid Gland (cytology)
• Water (metabolism)