Insulin degradation

The ECE isoforms show different subcellular distributions and enzymatic characteristics (Table 2). ECE-la and ECE-lc are mainly expressed at the cell surface, whereas ECE-lb, ECE-Id and ECE-2 are expressed intracellularly. Plasma membrane-bound ECE cleaves big-ET-1 circulating in the blood, whereas intracellular ECE isoforms are involved in the generation of mature endothelins. In addition, ECEs (as well as NEP and the insulin-degrading enzyme) contribute to the degradation of amyloid (3 (A 3) peptide. 

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Keywords Amyloid precursor protein Apolipoprotein E p-amyloid peptide Beta-amyloid precursor protein converting enzyme Insulin degrading enzyme Neurofibrillary tangle Oxidative damage Presenilin-1... 

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FiGURE 25 Spray dried insulin degradation to high molecular weight protein aggregates as a function of outlet air temperature. Source Adapted from Ref. 10. 

Degradation. On the first pass through the portal circulation, approximately 50% of the insulin is extracted by the liver, where it is degraded. Because the amount extracted is. variable, plasma insulin concentrations may not accurately reflect the rate of insulin secretion. Additional insulin degradation occurs in the kidneys. Insulin is filtered through the glomeruh, reabsorbed, and degraded in the proximal tubule. The basal insulin secretory rate is about 1 U/hr, with total daily secretion of about 40 U. The half-life of insulin in the circulation is between 4 and 5 minutes. 

Glycerol 3 phosphate dehydrogenase 3-Hydroxybutyrate dehydrogenase Insulysin (insulin degrading enzyme) Isocitrate dehydrogenase Lactate dehydrogenase Leucine aminopeptidase Lipase... 

Insulin-degrading enzyme inhibitors Peptide hydroxamate... 

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