Agonist of spexin-based galanin type 2 receptor and use thereof

Abstract

The present invention relates to spexin-based agonists specific for galanin receptor type 2 and use thereof. More specifically, the present invention provides peptide-based agonists with high specificity for galanin receptor type 2 and improved stability. The peptide-based agonists are involved in the regulation of in vivo physiological functions, such as food intake, anxiety, emotion, and addiction, for which galanin receptors type 2 is responsible, to effectively suppress appetite, help recover from anxiety disorder, and reduce pleasure addiction. Therefore, the peptide-based agonists can be used to prevent or treat galanin receptor type 2-mediated diseases.

The invention claimed is: 
     
       1. A peptide-based galanin receptor type 2 (GALR2) agonist comprising the amino acid sequence as set forth in SEQ ID NO: 48, SEQ ID NO: 50, or SEQ ID NO: 51. 
     
     
       2. A peptide-based galanin receptor type 2 (GALR2) agonist comprising the amino acid sequence as set forth in SEQ ID NO: 51. 
     
     
       3. The GALR2 agonist of  claim 1 , wherein the amino acid sequence is attached to polyethylene glycol (PEG), an acetyl (Ac) group, or Fmoc. 
     
     
       4. The GALR2 agonist of  claim 2 , wherein the amino acid sequence is attached to polyethylene glycol (PEG), an acetyl (Ac) group, or Fmoc. 
     
     
       5. The GALR2 agonist of  claim 1 , wherein the first amino acid in the amino acid sequence is d-Asparagine. 
     
     
       6. The GALR2 agonist of  claim 2 , wherein the first amino acid in the amino acid sequence is d-Asparagine. 
     
     
       7. The GALR2 agonist of  claim 1 , which specifically activates GALR2. 
     
     
       8. The GALR2 agonist of  claim 2 , which specifically activates GALR2. 
     
     
       9. The GALR2 agonist of  claim 1 , which does not activate GALR1 or GALR3. 
     
     
       10. The GALR2 agonist of  claim 2 , which does not activate GALR1 or GALR3. 
     
     
       11. The GALR2 agonist of  claim 7 , which does not activate GALR1 or GALR3. 
     
     
       12. The GALR2 agonist of  claim 8 , which does not activate GALR1 or GALR3. 
     
     
       13. A pharmaceutical composition comprising the GALR2 agonist of  claim 1  and a pharmaceutically acceptable carrier. 
     
     
       14. A pharmaceutical composition comprising the GALR2 agonist of  claim 2  and a pharmaceutically acceptable carrier. 
     
     
       15. The pharmaceutical composition of  claim 13 , which is a freeze-dried powder. 
     
     
       16. The pharmaceutical composition of  claim 13 , which is an injectable solution. 
     
     
       17. The pharmaceutical composition of  claim 14 , which is a freeze-dried powder. 
     
     
       18. The pharmaceutical composition of  claim 14 , which is a freeze-dried powder. 
     
     
       19. The pharmaceutical composition of  claim 13 , wherein the GALR2 agonist comprises the amino acid sequence as set forth in SEQ ID NO: 48. 
     
     
       20. The pharmaceutical composition of  claim 13 , wherein the GALR2 agonist B comprises the amino acid sequence as set forth in SEQ ID NO: 50.