| Popis: |
Rubiscolins, soymorphins, and oryzatensin are spinach RuBisCo, soy β-conglycinin, and rice albumin-derived opioid peptides, respectively. Rubiscolin-5 (YPLDL) and 6 (YPLDLF) have tyrosine at the N-terminal followed by a proline and leucine. Soymorphin-5 (YPFVV), 6 (YPFVVN), and 7 (YPFVVNA) show tyrosine at the N-terminal followed by proline and phenylalanine. Oryzatensin (GYPMYPLPR) shows a unique structure with glycine at the N-terminal followed by the tyrosine residue. Rubiscolins and soymorphins both act as opioid agonists for δ- and μ-opioid receptors, respectively. However, oryzatensin demonstrates antagonistic activity through μ-receptors. Rubiscolins enhance glucose uptake possibly through AMPK activation to increase GLUT4 translocation. Rubiscolin-6 stimulates food intake in the aged mice with an intact ghrelin resistance. These exorphins decrease the consumption of a high-fat diet possibly through activation of the central δ-opioid receptor system. These peptides are the potential exogenous complements that may aid the endogenous defense mechanisms of humans under stress conditions. Rubiscolins have a possible role in the regulation of the protective behavior in insects and the adaptation of young mammals. These exorphins have a role in anxiolysis and memory consolidation in mice. Soymorphins also play a role in anxiolysis, analgesia, food intake, and intestinal transit. Oryzatensin promotes phagocytic activity in PMNLs and the generation of superoxide ions from peripheral leukocytes. It has a potential role in immunomodulation through sensitization of cancer cells. Also, it improves amnesia induced by scopolamine and ischemia. Moreover, this peptide suppresses the food intake possibly through PGE2 generation and EP4 receptor activation. |
