Construction of GLP-1 receptor agonists using ELP and ABD as carriers and their hypoglycemic effects
Liu Changjiao
Cui Xiaobo
Tan Xiao
Abstract：Objective To construct glucagon-like peptide-1(GLP-1)receptor agonists using elastin-like polypeptide(ELP)and albumin-binding domain(ABD)as carriers and observe their hypoglycemic effects.Methods GLP-1 was genetically fused to ELP and ABD,generating the GLP-ELPAGV and GLP-ELPAGV-ABD fusion proteins.RINm-5F cells were treated with GLP-1,GLP-ELPAGV-ABD and GLP-ELPAGV at different concentrations,and then the cell proliferation promoting activity was detected.The effect of fusion protein on GLP-1 receptor(GLP-1R)affinity was determined by measuring the amount of cyclic adenosine monophosphate(cAMP)in RIN-m5F cells.The affinity between fusion protein and human serum albumin(HSA)was detected using ELISA.The blood glucose level was determined by using C57BL/6 mice at different time points after subcutaneous injection of fusion protein,and the in vivo hypoglycemic activity was explored.Results In vitro cell experiments showed that GLP-1,GLP-ELPAGV-ABD and GLP-ELPAGV fusion proteins all significantly promoted cell proliferation within the range of 100 nmol·L-1,and there was no signif-icant difference in their proliferation promoting ability(at 100 nmol·L-1,F=0.985,P=0.089).The binding affinities of GLP-ELPAGV and GLP-ELPAGV-ABD fusion proteins for GLP-1R decreased respectively within the range of 10 nmol·L-1(at 10 nmol·L-1,compar-ison between GLP-ELPAGV-ABD group and GLP-1 group t=4.542,P=0.004,comparison between GLP-ELPAGV group and GLP-1 group t=7.987,P<0.001).ELISA results showed that GLP-ELPAGV-ABD fusion protein still retained a high affinity for HSA.In vivo experiments showed that GLP-ELPAGV and GLP-ELPAGV-ABD fusion proteins could significantly reduce the blood glucose levels of mice for 72 h and 96 h(at 72 h:comparison between GLP-ELPAGV group and PBS group,t=3.811,P=0.008;at 96 h:comparison be-tween GLP-ELPAGV-ABD group and PBS group,t=3.559,P=0.003),respectively,which were much longer than that of natural GLP-1(only 1 h).Conclusion GLP-ELPAGV and GLP-ELPAGV-ABD fusion proteins can prolong the half-life of GLP-1 and significantly increase the hypoglycemic time of GLP-1.ELP and ABD show synergistic effect on boosting the hypoglycemic activity of GLP-1.
Keywords：Elastin-like polypeptideAlbumin-binding domainGlucagon-like peptide-1 receptor agonistsHypoglycemicHalf-lifeEscherichia coli
Publication Date：2025-07-25
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 747-751 )