Insulin decreases blood glucose concentration and increases cell permeability to monosaccharides, amino acids and fatty acids. Insulin accelerates glycolysis, the pentose phosphate cycle and glycogen synthesis in liver. Defects in insulin are the cause of familial hyperproinsulinemia. Insulin is available under the names Humulin or Humalog (Eli Lilly) and Novolin (Novo Nordisk) for the treatment of diabetes. After removal of the precursor signal peptide,Porcineroinsulin is post-translationally cleaved into two chains: peptide A and peptide Bovine, covalently linked by two disulfide bonds.