Insulin staining of pancreatic sections were consistent with changes in insulin secretion observed in Figure 4A with an increase in cell mass in SKO mice relative to WT mice ( Figure 4B )
Subsequent assay studies indicated that (R)-3-amino-1-(2-benzoyl-1,2-diazepan-1-yl)-4-(2,4,5-trifluorophenyl) butan-1-one (40) possesses strong in vitro activity, favorable selectivity, and in vivo efficacy in mouse models (Figure 6)
Site-specific PEGylation involves covalent attachment of polyethylene glycol (PEG) chains to predefined residues on the peptide backbone, forming a hydrophilic steric shield that reduces renal clearance, masks immunogenic epitopes, and protects against enzymatic degradation [189]
Options might include metoclopramide (limited to maximum 5 days' use due to risk of neurological side effects), prochlorperazine (which can cause drowsiness and dry mouth), or ondansetron (which may cause constipation and has QT-interval prolongation risks in some patients)
Moreover, several clinical studies show that glycemia improves when doses are increased but with unacceptable rates of gastrointestinal adverse events 16,17,18 , suggesting that maximum benefits from GLP-1R agonism are in fact not realized with current treatments