IRS1 and Insulin resistance: EGCG at low concentrations does not demonstrate activation of the IRS-1 gene, but it does show to be an inhibitor of gluconeogenesis in isolated hepatocytes. However, polyphenol-rich green tea increased the expression of the IRS1 gene in the muscle of the rat. The polyphenol-rich ethyl acetate fraction isolated from Molineria latifolia improves insulin resistance in experimental diabetic rats through the activation of IRS1/AKT, by altering the phosphorylation of gene-related serine and tyrosine residues.