Luteinizing hormone-releasing hormone (LHRH) is the key regulator of the hypothalamic-pituitary-gonadal (HPG) axis, which is responsible for the development and functioning of the reproductive system. Delivery of a co...Luteinizing hormone-releasing hormone (LHRH) is the key regulator of the hypothalamic-pituitary-gonadal (HPG) axis, which is responsible for the development and functioning of the reproductive system. Delivery of a continuous supply of LHRH agonists causes down-regulation of the LHRH receptors, resulting in a marked decrease in androgens in males and estrogens in females. LHRH analogues are widely used in the treatment of various diseases, including prostate and breast cancer, and reproductive disorders, such as infertility and precocious puberty. However, they require parenteral administration, and no oral formulations are currently available. We synthesized two types of LHRH mini-dendrimers using thioether ligation, aiming to enhance the stability and bioavailability of the peptide drug while maintaining its biologically active conformation. These two compounds include a poly-lysine core conjugated to either the C-terminus of LHRH or a D-amino acid in position 6 of the LHRH sequence. The synthesized dendrimers were analysed using dynamic light scattering, and showed particle sizes of 155 and 115 nm, respectively. The nanometer size, well-defined structure and water solubility of these dendritic analogues make them excellent candidates for further exploration in oral peptide drug delivery.展开更多
Endomorphin-1 is an endogenous opioid peptide that mediates pain relief through interaction with the μ-opioid receptor in the central nervous system. To enhance the metabolic stability of this tetrapeptide, cyclisati...Endomorphin-1 is an endogenous opioid peptide that mediates pain relief through interaction with the μ-opioid receptor in the central nervous system. To enhance the metabolic stability of this tetrapeptide, cyclisation through the formation of a disulfide bridge between the side chains of cysteine residues added to the sequence was explored. A further increase in stability was achieved through N-terminal modification with lipoamino acid and lactose succinamic acid, and the inclusion of D-amino acids. The latter also provided an alternative spatial arrangement of the aromatic side chains. The lipidated cyclic derivatives were insoluble in aqueous buffer, however, the cyclic peptides and glycopeptides showed greatly improved stability towards enzymatic degradation in human plasma.展开更多
文摘Luteinizing hormone-releasing hormone (LHRH) is the key regulator of the hypothalamic-pituitary-gonadal (HPG) axis, which is responsible for the development and functioning of the reproductive system. Delivery of a continuous supply of LHRH agonists causes down-regulation of the LHRH receptors, resulting in a marked decrease in androgens in males and estrogens in females. LHRH analogues are widely used in the treatment of various diseases, including prostate and breast cancer, and reproductive disorders, such as infertility and precocious puberty. However, they require parenteral administration, and no oral formulations are currently available. We synthesized two types of LHRH mini-dendrimers using thioether ligation, aiming to enhance the stability and bioavailability of the peptide drug while maintaining its biologically active conformation. These two compounds include a poly-lysine core conjugated to either the C-terminus of LHRH or a D-amino acid in position 6 of the LHRH sequence. The synthesized dendrimers were analysed using dynamic light scattering, and showed particle sizes of 155 and 115 nm, respectively. The nanometer size, well-defined structure and water solubility of these dendritic analogues make them excellent candidates for further exploration in oral peptide drug delivery.
文摘Endomorphin-1 is an endogenous opioid peptide that mediates pain relief through interaction with the μ-opioid receptor in the central nervous system. To enhance the metabolic stability of this tetrapeptide, cyclisation through the formation of a disulfide bridge between the side chains of cysteine residues added to the sequence was explored. A further increase in stability was achieved through N-terminal modification with lipoamino acid and lactose succinamic acid, and the inclusion of D-amino acids. The latter also provided an alternative spatial arrangement of the aromatic side chains. The lipidated cyclic derivatives were insoluble in aqueous buffer, however, the cyclic peptides and glycopeptides showed greatly improved stability towards enzymatic degradation in human plasma.
