Nutrient Combinations Sensed by L-Cell Receptors Potentiate GLP-1 Secretion
Nalini Sodum1, Orvokki Mattila1, Ravikant Sharma1
1Research Unit of Biomedicine and Internal Medicine, Biocentre of Oulu, Medical Research Center, University of Oulu, Oulu University Hospital, Aapistie 5, 90220 Oulu, Finland.
International Journal of Molecular Sciences
|January 23, 2024
Summary
Combinations of alpha-linolenic acid with phenylalanine or tryptophan significantly boost glucagon-like peptide-1 (GLP-1) release. These nutrient pairings show potential for obesity management by enhancing GLP-1 secretion.
Area of Science:
- Endocrinology
- Nutritional Science
- Gastroenterology
Background:
- Obesity is a significant risk factor for cardiometabolic diseases.
- Glucagon-like peptide-1 (GLP-1) plays a role in appetite regulation but has a short half-life and limited systemic circulation.
- L-cells, responsible for GLP-1 release, are located distally, while nutrient absorption occurs proximally.
Purpose of the Study:
- To investigate if combinations of amino acids and fatty acids can potentiate GLP-1 release through distinct L-cell receptors.
- To explore novel nutrient strategies for enhancing GLP-1 secretion.
Main Methods:
- GLP-1 secretion was measured in mouse STC-1 enteroendocrine cells.
- Cells were treated with alpha-linolenic acid (αLA), phenylalanine (Phe), tryptophan (Trp), and their combinations.
- Gene expression, including GPR120, was analyzed via qPCR, and GLP-1 levels were quantified.
Main Results:
- Alpha-linolenic acid (αLA) alone significantly stimulated GLP-1 secretion.
- Phenylalanine (Phe) and tryptophan (Trp) demonstrated a dose-dependent increase in GLP-1 secretion.
- Combined αLA with Phe or Trp significantly enhanced GLP-1 secretion more than individual nutrients. αLA and Trp upregulated GPR120.
Conclusions:
- Specific combinations of amino acids and fatty acids synergistically enhance GLP-1 secretion.
- These findings suggest potential for nutrient-based interventions, possibly in sustained-release formulations targeting the colon.
- This approach may offer a novel strategy for appetite suppression and obesity prevention.
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