Characterization of Optimized Functional-Complementary Dual Insulinotorpic Peptide rolGG

Curr Pharm Biotechnol. 2017;18(10):840-848. doi: 10.2174/1389201019666171204111908.

Abstract

Background: Glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP) play a similar but complementary role in the regulation of glucose levels in islet β-cells. This study was aimed to develop a fusion peptide, which combines 4 tandem repeated GLP-1 and 4 tandem repeated GIP (4rolGG), and to investigate its therapeutic effect on type 2 diabetes using a diabetic mice model.

Methods: A 4rolGG expression plasmid was constructed and expressed in BL21 (DE3). By inducting with IPTG, 4rolGG was expressed at a high level, which was confirmed by SDS-PAGE electrophoresis and Western Blotting. Subsequently, 4rolGG was purified by Ni-NTA affinity chromatography and the purity of 4rolGG was up to 90%.

Result and conclusion: After oral administration of 4rolGG for 4 weeks, streptozotocin-induced diabetic mice showed a dramatic reduction in the levels of plasma glucose, GHbA1C, TC and TG, while the insulin levels were increased significantly.

Keywords: GIP; GLP-1; diabetes; expression; primers; purification.

MeSH terms

  • Administration, Oral
  • Amino Acid Sequence
  • Animals
  • Blood Glucose / analysis
  • Diabetes Mellitus, Experimental / drug therapy*
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Gastric Inhibitory Polypeptide / chemistry*
  • Gastric Inhibitory Polypeptide / genetics
  • Glucagon-Like Peptide 1 / chemistry*
  • Glucagon-Like Peptide 1 / genetics
  • Humans
  • Insulin / blood
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Peptide Fragments / chemistry
  • Peptide Fragments / genetics
  • Peptide Fragments / therapeutic use*
  • Plasmids
  • Protein Engineering

Substances

  • Blood Glucose
  • Insulin
  • Peptide Fragments
  • Gastric Inhibitory Polypeptide
  • Glucagon-Like Peptide 1