LIPIDIC CONJUGATES OF LUTEINIZING-HORMONE-RELEASING HORMONE (LHRH)+ AND THYROTROPIN-RELEASING-HORMONE (TRH)+ THAT RELEASE AND PROTECT THE NATIVE HORMONES IN HOMOGENATES OF HUMAN INTESTINAL EPITHELIAL (CACO-2) CELLS

The enzymatically labile peptides LHRH and TRH were conjugated to various lipidic peptides. The conjugates and free peptides were incubated with Caco-2 cell homogenates and their respective degradation profiles were studied following incubation. Conjugation to lipidic peptides increased the half-life of LHRH and TRH. The Caco-2 cell homogenates were capable of cleaving the conjugated lipidic peptide, to release the parent LHRH or TRH. The released LHRH or TRH subsequently demonstrated a longer half-life than when present alone in the incubation mixture, suggesting that the cleaved lipidic peptide is capable of inhibiting enzymes.