ABSTRACT
This chapter describes the main nutraceuticals with evidence of a certain action on glycemia and insulin resistance. Insulin resistance is a condition characterized by a reduced capacity of muscular, adipose, and liver cells to respond to insulin; these cells become less sensitive to the action of insulin, making more insulin needed to perform the same actions. Curcuma improved insulin resistance in skeletal muscles through the activation of MAP-kinase and the oxidation of fatty acids. Curcuma is obtained from the Curcuma longa plant: its main constituent, curcumin, is a polyphenol with the ability to modulate numerous signal transmission mechanisms. Berberine is a standardized extract of Berberis aristata, an Indian medicinal plant of the Berberidaceae family, an isoquinolinic alkaloid that has been shown to decrease glucose levels and improve insulin resistance through activating of MAP-kinase and increasing the phosphorylation of insulin receptors.
