The Isocitrate Dehydrogenase Activity Assay kit provides a simple and direct procedure for measuring NADP-+- dependent IDH activity in serum. The activity is determined using isocitrate as the substrate in IDH enzyme reaction. As a result ofthis reaction a change of absorbance at 340 nm is abserved, proportional to the enzymatic activity of IDH One unit of IDHis the amount of enzyme that will generate 1.0 pimole of NADPH per minute at pH 8.0 and 37 °C.
Isocitrate dehydrogenase (IDH=EC:184.108.40.206) is an enzyme that converts isocitrate to alpha-ketoglutarate ( -KG) and carbondioxide(CO2). There are three isozymes of IDH (IDH1, IDH2 and IDH3), the IDH1 and IDH2 are NADP-dependent and the IDH3 utilize NAD as cofactor. NAD-dependent IDH3 is located in mitochondria and is well known for its central role for energy production in the Krebs cycle. NADP-dependent IDHs (EC 220.127.116.11) are primarily located either in cytoplasm (IDH1) or mitochondria(IDH2). Both IDH1 and IDH2 play important roles in a number of cellular metabolic functions, including glucose sensing, glutamine metabolism, lipogenesis, and regulation of cellular redox status.
IDH activity significantly increases in human serum in parenchymal diseases of liver . Although activity of mutant IDH is elevatedin cancers like glioblastomas(GBM) , acute myeloid leukemia(AML) , intrahepatic cholangiocarcinoma_; particularly in the early phases of cancer, an increase is also observed in normal ype of IDH enzyme activity.