For the GLP-1R siRNA experiment a pool of 4 prevalidated siRNA designed for human GLP1R were used (Dharmacon Accell si RNA reagents, Thermo Scientific, Milan, Italy).
To demonstrate that GLP-1 activated intracellular kinases via its cognate receptor, we downregulated GLP1R expression through siRNA.
Previous immunohistochemical studies showed that GLP1R expression was mainly in the inner retina .
Robert Lutjens, head of biology at Addex Pharmaceuticals, said that GIPR and GLP1R
are present together in pancreatic and nerve cells, and their roles in Type 2 diabetes make them important targets for the development of new drugs.
To investigate the relationship between the SNPs of GLP1R and the effectiveness of GLP-1 analogue treatment in patients with type 2 diabetes mellitus, we performed exon resequencing of the GLP1R gene in patients with poorly controlled type 2 diabetes mellitus who were treated with a GLP-1 analogue in this study.
DNA Extraction and Direct Resequencing of the GLP1R Gene.
Associations of GLP1R Genetic Variations with Drug Responsiveness.
The effects of GLP1R genotypes on glucose, insulin, and C-peptide concentrations during the 75 g OGTT after GLP-1 analogue treatment are shown in Figure 3.
To the best of our knowledge, this is the first study to reveal the relationship between genetic variations of GLP1R and the response to a GLP-1 analogue in patients with type 2 diabetes mellitus, although the number of enrolled cases in this study is limited.
The expression of a nonsynonymous SNP (rs367543060), which results in the substitution of methionine for threonine at position 149 of GLP1R in cell systems, has been documented to decrease binding affinity for GLP-1 and intracellular signaling after hormone receptor binding [12, 25].
The application of chimeric GLP-1/GIP peptides together with molecular modeling suggests that [His.sup.1] of GLP-1 interacts with Asn302 of GLP1R, and that [Thr.sup.7] of GLP-1 has close contact with a binding pocket formed by [Ile.sup.196], [Leu.sup.232], and [Met.sup.233] of GLP1R .