Potential role of galanine in the treatment of type 2 diabetes mellitus

The growing incidence of diabetes mellitus requires the optimizing of existing approaches and searching for new ones to treat this disease. It is necessary to study the features of other regulators that play a significant role in the process of glucose uptake by cells, along with the insulin resistance caused by defects in the molecular mechanisms of insulin action. Galanine, a neuropeptide of 29 (30 in humans) amino acids, is involved in a large number of different vital functions, including regulating energy metabolism in the cell. Galanine interacts with three G protein-coupled receptors, GAL1, GAL2, and GAL3, and transmitting signals through several transduction pathways, including cAMP/PKA inhibition (GAL1, GAL3) and phospholipase C (GAL2) stimulation. Agonists and antagonists of galanine receptor subtype GalR1-3 can be used as intended therapeutic targets to treat various human diseases. We accumulated more data that prove the importance of the galanine peptide regulator in the etiology of impaired glucose uptake by insulin-dependent tissues. The review considers such effects of galanine, as inhibition of insulin synthesis, activation of expression and translocation to the plasma cell membrane of the glucose transporter GLUT4, increase of PPAR-g level, and decrease in duodenal hyper-contractility. These data confirm the importance of research to find an effective antidiabetic drug among the synthesized analogs of galanine.

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