Stability of Synthetic Exendin-4 in Human Plasma In Vitro

Sites of exendin-4 that that are relatively susceptible to degradation in plasma were identified with the aim of providing information for designing new exendin-4 analogues. The stability of exendin-4 in human plasma was evaluated in vitro. The results showed that the peptide was slowly degraded with a half-life of 9.57 h and the principal cleavage sites are between Thr5 and Phe6, Phe6 and Thr7, and Thr7 and Ser8 of the N-terminus region of exendin-4. Keywords: Synthetic exendin-4, Glucagon-like peptide, Stability, Dipeptidyl peptidase-IV(DPP- V)