Generation of Efficient Selenocysteine-containing Peptides with GPX Activities

摘要

Glutathione peroxidase (GPX) is a mammalian selenium-containing anti-oxidant enzyme. Based on the structure of the active site in bovine GPX, a novel selenocysteine-containing 5-mer peptide (H-Arg-Sec-Gly-Arg-Asn-OH) was successfully synthesized to imitate GPX. Its GPX activity could reach to 11 U/mumol, that was 11 times as much as that of ebselen. The 5-mer peptide has its special advantages in low molecular weight, improved cell membrane permeability, good water-solubility and stability compared with other pervious GPX mimics. The effect of this GPX mimic on ischemia-reperfusion injury of the liver was examined in rats. The increases in serum hepatic amino-transferases, tissue MDA, and the decrease in tissue GPX activity were significantly inhibited by treatment with the 5-mer peptide. It may protect liver from ischemia-reperfusion injury.