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Mammalian aquaporins: diverse physiological roles and potential clinical significance

Published online by Cambridge University Press:  16 May 2008

A. S. Verkman
A. S. Verkman
Affiliation:
Departments of Medicine and Physiology, Cardiovascular Research Institute, 1246 Health Sciences East Tower, University of California, San Francisco, CA 94143-0521, USA. Tel: +1 415 476 8530; Fax: +1 415-665-3847; E-mail: alan.verkman@ucsf.edu
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Abstract

Aquaporins have multiple distinct roles in mammalian physiology. Phenotype analysis of aquaporin-knockout mice has confirmed the predicted role of aquaporins in osmotically driven transepithelial fluid transport, as occurs in the urinary concentrating mechanism and glandular fluid secretion. Aquaporins also facilitate water movement into and out of the brain in various pathologies such as stroke, tumour, infection and hydrocephalus. A major, unexpected cellular role of aquaporins was revealed by analysis of knockout mice: aquaporins facilitate cell migration, as occurs in angiogenesis, tumour metastasis, wound healing, and glial scar formation. Another unexpected role of aquaporins is in neural function – in sensory signalling and seizure activity. The water-transporting function of aquaporins is likely responsible for these roles. A subset of aquaporins that transport both water and glycerol, the ‘aquaglyceroporins’, regulate glycerol content in epidermal, fat and other tissues. Mice lacking various aquaglyceroporins have several interesting phenotypes, including dry skin, resistance to skin carcinogenesis, impaired cell proliferation, and altered fat metabolism. The various roles of aquaporins might be exploited clinically by development of drugs to alter aquaporin expression or function, which could serve as diuretics, and in the treatment of brain swelling, glaucoma, epilepsy, obesity and cancer.

Type
Review Article
Information
Expert Reviews in Molecular Medicine , Volume 10 , October 2008 , e13
Copyright
Copyright ©Cambridge University Press 2008

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Further reading, resources and contacts

General information on aquaporins:

http://www.ucsf.edu/verklabGoogle Scholar
http://www.ks.uiuc.edu/Research/aquaporins/Google Scholar
http://en.wikipedia.org/wiki/AquaporinGoogle Scholar
http://www.congre.co.jp/aqp2007/Google Scholar
http://www.scanbalt.org/sw14185.aspGoogle Scholar
http://www.ndif.orgGoogle Scholar