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Updated: Sep 3, 2025
07:29
Real-time Analysis of Gut-brain Neural Communication: Cortex wide Calcium Dynamics in Response to Intestinal Glucose Stimulation
Published on: December 29, 2023
740
A glucokinase-linked sensor in the taste system contributes to glucose appetite
Sandrine Chometton1, A-Hyun Jung1, Lilly Mai1
1Department of Biological Sciences, University of Southern California, Los Angeles, CA, 90089, USA.
Molecular Metabolism
|July 23, 2022
Summary
Glucokinase, an enzyme, is present in taste bud cells and influences the taste and preference for glucose. This discovery sheds light on how the mouth detects nutrients and triggers reward responses.
Area of Science:
- Neuroscience
- Metabolism
- Sensory Biology
Background:
- Dietary glucose strongly influences reward responses and food intake, but the peripheral sensors involved are not fully understood.
- Glucokinase (GCK) is a known glucose-sensing enzyme, but its role in taste perception was unclear.
Purpose of the Study:
- To investigate if glucokinase is expressed in taste bud cells.
- To determine if glucokinase contributes to the hedonic appeal and intake of glucose.
Main Methods:
- Localization of glucokinase gene transcripts in mouse taste buds using RNAScope®.
- Real-time qPCR to assess glucokinase mRNA levels in taste papillae.
- Pharmacological activation and genetic silencing of glucokinase in taste fields.
- Taste preference tests comparing glucose, fructose, and sucralose.
Main Results:
- Glucokinase mRNA was found in taste bud cells and upregulated by fasting and sugar access.
- Activating glucokinase enhanced responses to glucose but not fructose.
- Silencing glucokinase reduced glucose-stimulated licking, particularly in mice lacking sweet receptors.
- Reduced lingual glucokinase impaired acquired preference for glucose over fructose.
Conclusions:
- Glucokinase plays a role in sensing glucose in the oral cavity.
- This finding advances the understanding of orosensory mechanisms in nutrition, metabolism, and food reward.
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