International Journal of Experimental Diabetes Research
Volume 3 (2002), Issue 1, Pages 47-60
doi:10.1080/15604280212528
D-Chiro-Inositol – Its Functional Role in Insulin Action and its Deficit in Insulin Resistance
1Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA
2Insmed Inc., PO Box 2400, Glen Allen,, VA 23058, USA
Copyright © 2002 Joseph Larner. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
In this review we discuss the biological significance
of D-chiro-inositol, originally discovered
as a component of a putative mediator of
intracellular insulin action, where as a putative
mediator, it accelerates the dephosphorylation
of glycogen synthase and pyruvate dehydrogenase,
rate limiting enzymes of non-oxidative
and oxidative glucose disposal.
Early studies demonstrated a linear relationship
between its decreased urinary excretion
and the degree of insulin resistance present.
When tissue contents, including muscle, of type
2 diabetic subjects were assayed, they demonstrated
a more general body deficiency.
Administration of D-chiro-inositol to diabetic
rats, Rhesus monkeys and now to humans
accelerated glucose disposal and sensitized
insulin action.
A defect in vivo in the epimerization of myoinositol to chiro-inositol in insulin sensitive tissues
of the GK type 2 diabetic rat has been elucidated.
Thus, administered D-chiro-inositol
may act to bypass a defective normal epimerization
of myo-inositol to D-chiro-inositol
associated with insulin resistance and act to at
least partially restore insulin sensitivity and glucose
disposal.