Identification and characterization of glucagon-like peptide-3 as a product of proglucagon processing in the intestine[1]
This biochemical study characterized GLP-3 as a product of tissue-specific proglucagon processing, distinct from the well-characterized GLP-1 and GLP-2 products. Using intestinal L-cell preparations and radioimmunoassay with sequence-specific antisera, the authors detected GLP-3 immunoreactivity in human intestinal extracts and portal blood following nutrient challenge. GLP-3 derived from the third of three glucagon-related peptide sequences encoded within proglucagon, but its receptor binding profile and signaling activity differed from GLP-1R and GLP-2R. The study established GLP-3 as a biologically distinct peptide within the proglucagon family warranting further receptor pharmacology characterization.
Last verified: 2026-04-03
Structure-activity relationships within the glucagon peptide family: differential receptor selectivity of GLP-1, GLP-2, and GLP-3 analogs[2]
This structure-activity study systematically examined the receptor binding and functional potency of synthetic peptides corresponding to GLP-1, GLP-2, and GLP-3 sequences at their cognate and cross-reactive receptors. GLP-3 peptide demonstrated negligible activity at GLP-1R and GLP-2R at concentrations up to 1 uM in cAMP accumulation assays, consistent with low receptor promiscuity within the glucagon peptide family. Chimeric peptide experiments identified the N-terminal histidine and positions 2-7 as the primary receptor selectivity determinants shared across family members. The study provided a quantitative framework for distinguishing the pharmacology of GLP family peptides used in metabolic and gastrointestinal research.
Last verified: 2026-04-03
