glucagon-like peptide-1

Overview

Glucagon-like peptide-1 (GLP-1) is a peptide hormone with important roles in glucose homeostasis and energy balance. It is produced primarily by enteroendocrine L-cells in the intestine and acts as an incretin, meaning it enhances glucose-dependent insulin secretion after nutrient intake. In biomedical research and therapeutics, GLP-1 is widely studied for its metabolic effects, including regulation of insulin secretion, appetite, and glycemic control in type 2 diabetes.

A key feature of GLP-1 biology is its rapid inactivation by Dipeptidyl peptidase 4 (DPP4), which limits its circulating activity. Because of this, many studies focus on either increasing endogenous GLP-1 secretion or preventing its degradation. GLP-1 is therefore relevant not only as a hormone but also as a therapeutic target and biomarker in metabolic disease, obesity, and related cardiometabolic conditions.

Focus of Latest Publications

Recent publications have focused on glucagon-like peptide-1 (GLP-1) mainly in the context of metabolic regulation, obesity, and glucose homeostasis. In bariatric surgery, GLP-1 therapies were discussed as emerging adjunctive treatments for patients with suboptimal early weight loss, highlighting interest in GLP-1 as a post-procedural management strategy rather than as a direct intervention in the study itself. In type 2 diabetes research, GLP-1 was also included among several metabolic biomarkers of interest alongside insulin resistance-related regulators such as GLUT4, PI3K, SIRT6, nesfatin-1, leptin, and IGF1.

Several studies examined interventions that may influence endogenous GLP-1 secretion or activity. A review of bioactive polysaccharides and gut microbiota in type 2 diabetes described how microbial metabolites such as short-chain fatty acids and secondary bile acids can modulate glycemic control through GPR41/43, FXR, and TGR5 signaling, promoting GLP-1 secretion and improving insulin sensitivity. Similarly, a study of Bifidobacterium triple viable capsules and Five-animal Play in patients with impaired glucose tolerance identified GLP-1 modulation as a possible treatment approach, although the abstract does not report specific GLP-1 outcomes.

Direct experimental evidence for GLP-1 modulation was reported in an in vitro study of whole apple and apple pomace digesta. Using Caco-2 monolayers and STC-1 L-cells, the investigators found that apple and pomace inhibited transepithelial glucose transport, and that gastric digesta from both sources increased GLP-1 secretion by 50%. After intestinal digestion, pomace digesta retained this effect, increasing GLP-1 by 179% versus glucose controls and 62% versus intestinal blank controls. The authors suggested that pomace intake may help attenuate postprandial glycemia and regulate appetite.

Another publication highlighted GLP-1 as a cardioprotective peptide targeted by microbial degradation. In a murine ischemia/reperfusion model, Bacteroides acidifaciens was shown to produce a Dipeptidyl peptidase 4 isozyme that degrades plasma GLP-1, thereby amplifying myocardial injury. Pharmacological inhibition of this microbial DPP4 with daurisoline mitigated cardiac dysfunction, and in acute myocardial infarction patients, B. acidifaciens abundance and BaDPP4 levels correlated with markers of cardiac damage.

Key Publications

• May Incidence and Predictors of Suboptimal Early Weight Loss after Bariatric Procedures. (Obesity surgery, 2026, PMID 42174245): "Identifying predictors of early inadequate weight loss is increasingly relevant as glucagon-like peptide-1 (GLP1) therapies emerge as adjunctive treatments."
• May Effects of Psyllium Husk on Metabolic Regulators, Insulin Resistance, and SIRT6 in Liver and Muscle of Type 2 Diabetic Rats. (Veterinary medicine and science, 2026, PMID 41940860): "Biomarkers like glucose transporter type 4 (GLUT4), phosphoinositide 3-kinase (PI3K), sirtuin 6 (SIRT6), nesfatin-1, glucagon-like peptide 1 (GLP-1), leptin, and insulin-like growth factor 1 (IGF-1) play important roles in various physiological processes."
• May Bacteroides acidifaciens exacerbates cardiac ischemia/reperfusion injury via the microbial-host isozyme DPP4. (Cell host & microbe, 2026, PMID 41923637): "B. acidifaciens produces dipeptidyl peptidase 4 (BaDPP4), which degrades cardioprotective peptides (e.g., glucagon-like peptide-1 [GLP-1]) in the plasma, amplifying myocardial injury."
• May Pharmacological and metabolic effects of Bifidobacterium triple viable capsules and Five-animal Play in patients with impaired glucose tolerance. (Pakistan journal of pharmaceutical sciences, 2026, PMID 41879385): "Wingless-type MMTV integration site family member 5a/ secreted frizzled-related protein 5 (Wnt5a/Sfrp5) signaling and GLP-1 modulation have been identified as possible treatment approaches."
• Apr A review on molecular crosstalk: Bioactive polysaccharides and gut microbiota in type 2 diabetes-Pathways, signaling, and therapeutic translation. (International journal of biological macromolecules, 2026, PMID 41850461): "In parallel, SCFA and SBAs modulate glycemic control via GPR41/43, FXR and TGR5 signaling, promoting glucagon-like peptide-1 (GLP-1) secretion and enhancing insulin sensitivity."
• May Selective detoxification of digesta revealed how cold-pressed apple fractions modulate transepithelial glucose transport and stimulate GLP-1 secretion. (Food chemistry, 2026, PMID 41775012): "This study examined whether whole apple and apple pomace modulate transepithelial glucose transport and GLP-1 secretion under physiologically relevant in vitro conditions."