Article

Pyridoxamine: the many virtues of a maillard reaction inhibitor.

Division of Nephrology, Vanderbilt University Medical Center, S-3223 MCN, 1161 21st Avenue South, Nashville, TN 37232-2372, USA.
Annals of the New York Academy of Sciences (impact factor: 3.15). 07/2005; 1043:807-16. DOI:10.1196/annals.1333.093 pp.807-16
Source: PubMed

ABSTRACT Pyridoxamine (PM) is one of three natural forms of vitamin B6. It is a critical transient intermediate in catalysis of transamination reactions by vitamin B6-dependent enzymes. The discovery eight years ago that PM can inhibit the Maillard reaction stimulated new interest in this B6 vitamer as a prospective pharmacological agent for treatment of complications of diabetes. PM application in diabetic nephropathy has now progressed to a phase III clinical trial. Investigation of the PM mechanism of action demonstrated that PM inhibits post-Amadori steps of the Maillard reaction by sequestering catalytic metal ions and blocking oxidative degradation of Amadori intermediate. PM also has the capacity to scavenge toxic carbonyl products of sugar and lipid degradation, and to inhibit reactive oxygen species. These multiple activities position PM as a promising drug candidate for treatment of multifactorial chronic conditions in which oxidative reactions and/or carbonyl compounds confer pathogenicity.

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Keywords

B6 vitamer
 
catalysis
 
diabetic nephropathy
 
inhibits post-Amadori steps
 
lipid degradation
 
Maillard reaction
 
multifactorial chronic conditions
 
multiple activities position
 
new interest
 
oxidative degradation
 
oxidative reactions
 
pathogenicity
 
phase III clinical trial
 
reactive oxygen species
 
scavenge toxic carbonyl products
 
sequestering catalytic metal ions
 
vitamin B6
 
vitamin B6-dependent enzymes