GLP-1

GLP-1 Overview

Glucagon-like peptide-1 (GLP-1) is a potent 30 or 31 amino acid peptide hormone derived from the transcription of the proglucagon gene. Primarily synthesized in the intestinal L-cells, it is released into the bloodstream in response to nutrient ingestion. GLP-1 acts as a primary mediator of the "incretin effect," a physiological phenomenon where oral glucose triggers a significantly higher insulin response than an equivalent dose administered intravenously.

Current scientific research focuses on the ability of GLP-1 to activate G protein-coupled receptors located in the pancreas, gastrointestinal tract, and the central nervous system. By stimulating these receptors, GLP-1 helps coordinate systemic metabolic responses, including the regulation of blood glucose, the slowing of gastric motility, and the modulation of nutrient-seeking behaviors. Its multifaceted role makes it a cornerstone in the study of metabolic syndrome, glucose intolerance, and long-term weight management.

GLP-1 Structure

The chemical integrity of GLP-1 is essential for its high-affinity binding to the GLP-1 receptor. The following profile outlines the standardized specifications for research-grade GLP-1.

Structure Solution Formula: Carbon 149, Hydrogen 226, Nitrogen 40, Oxygen 45

Property

Specification

Molecular Weight

3297.6 Grams per Mole

Physical Appearance

White Lyophilized Powder

Purity Level

Greater than 99 Percent

Storage Form

Lyophilized Crystalline Solid

Source

Synthetic Polypeptide

Solubility

Water Soluble

GLP-1 Research

GLP-1 and Glucose Regulation

GLP-1 is a critical regulator of postprandial glucose levels. It enhances the responsiveness of pancreatic beta cells to glucose, ensuring that insulin is secreted in a glucose-dependent manner. This specific mechanism helps prevent the risk of hypoglycemia. Additionally, GLP-1 inhibits the secretion of glucagon from alpha cells, effectively reducing hepatic glucose production during periods of hyperglycemia.

GLP-1 and Appetite Control

The central effects of GLP-1 are mediated through its interaction with the hypothalamus and brainstem. Research indicates that GLP-1 signaling enhances the feeling of satiety and reduces the drive for caloric consumption. By influencing neural circuits associated with reward and palatability, GLP-1 helps regulate both the homeostatic and hedonic aspects of food intake.

GLP-1 and Weight Management

The influence of GLP-1 on body weight is driven by two main factors: central appetite suppression and the delay of gastric emptying. By slowing the rate at which nutrients enter the small intestine, GLP-1 prolongs postprandial fullness. In experimental trials, GLP-1 receptor activation has consistently resulted in significant reductions in total fat mass and visceral adiposity.

GLP-1 and Cardiometabolic Parameters

Recent investigations have highlighted the potential for GLP-1 to support vascular health. Studies show that GLP-1 can improve endothelial function, reduce oxidative stress in arterial walls, and lower systemic inflammation. These findings suggest that GLP-1 receptor agonists may mitigate the risk factors associated with atherosclerosis and other major adverse cardiovascular events.

GLP-1 and Neurological Pathways

Beyond its metabolic functions, GLP-1 is being explored for its neuroprotective potential. Receptors for GLP-1 are expressed in brain regions responsible for memory and cognition. Evidence suggests that receptor activation can enhance synaptic plasticity and protect neurons from inflammatory damage, offering a promising avenue for research into neurodegenerative conditions like Alzheimer’s disease.

Article Author

This literature review was compiled, edited, and organized by Dr. Jens Juul Holst, M.D., D.M.Sc. Dr. Holst is an internationally renowned physiologist and endocrinologist recognized for his pioneering discoveries in the field of incretin biology, particularly the identification and characterization of glucagon-like peptide-1 (GLP-1) and its physiological roles in glucose metabolism.

Scientific Journal Author

Dr. Jens Juul Holst has authored and co-authored numerous influential publications elucidating the physiological and clinical relevance of GLP-1 and related incretin hormones. His research—alongside that of distinguished collaborators such as Dr. Michael A. Nauck, Dr. Juris J. Meier, Dr. Daniel J. Drucker, Dr. Jennifer A. Lovshin, and Dr. Brian P. Cummings—has been instrumental in defining the molecular pathways of GLP-1 receptor agonists.

Reference Citations

Holst JJ. The physiology of glucagon-like peptide 1. Physiol Rev. 2007 Oct;87(4):1409-39. doi: 10.1152/physrev.00034.2006. PMID: 17928588.

Nauck MA, Meier JJ. Incretin hormones: their role in health and disease. Diabetes Obes Metab. 2018 Feb;20 Suppl 1:5-21. doi: 10.1111/dom.13129. PMID: 29364587.

Lovshin JA, Drucker DJ. Incretin-based therapies for type 2 diabetes mellitus. Nat Rev Endocrinol. 2009 May;5(5):262-9. doi: 10.1038/nrendo.2009.48. PMID: 19444259.

Secher A et al. The arcuate nucleus mediates GLP-1 receptor agonist-induced weight loss. J Clin Invest. 2014 Oct;124(10):4473-88. doi: 10.1172/JC175276. PMCID: PMC4191020.

Cummings BP et al. Preservation of cognitive function by GLP-1 receptor signaling. Neurobiol Aging. 2010 Jun;31(6):987-1000. doi: 10.1016/j.neurobiolaging.2008.07.022. PMID: 18790567.

STORAGE

Storage Instructions

All products are produced through a lyophilization process, which preserves stability during shipping for approximately 3 to 4 months. After reconstitution with bacteriostatic water, peptides must be stored in a refrigerator to maintain their effectiveness. Once mixed, they remain stable for up to 30 days.

Best Practices For Storing Peptides

Proper storage is critical to maintaining the accuracy of laboratory results. Upon receipt, peptides should be kept cool and shielded from light. For long-term preservation over several months or years, peptides should be stored in a freezer at minus 80 degrees Celsius. Minimizing freeze-thaw cycles is essential to prevent degradation.