Antidiabetic vanadium(IV) and zinc(II) complexes

Diabetes mellitus (DM), which develops many secondary complications such as atherosclerosis, microangiopathy, renal dysfunction and failure, cardiac abnormality, diabetes retinopathy and ocular disorders, is classified as either insulin-dependent type I or non-insulin-dependent type 2, according to the definition of WHO. Although several types of insulin preparations for type 1 DM and those of synthetic drugs for type 2 DM have been developed and clinically used, they have several problems such as physical and mental pain due to daily insulin injections and defects involving side effects, respectively. In the 21st century, a new class of pharmaceuticals should be introduced. For this reason, metallopharmaceutical compounds containing vanadium and zinc ions are expected to treat both types of DM, by making effective use of unique characteristics of the metals. In this article, the current state of development of insulin-mimetic vanadium and zinc complexes with different coordination modes are reviewed, focusing on the preparations and coordination structures of the complexes and in vitro and in vivo evaluations as well as the possible mechanism. (C) 2002 Elsevier Science B.V. All rights reserved.