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Updated: May 23, 2026
08:24
Multi-Photon Laser Ablation of Cytoplasmic Microtubule Organizing Centers in Mouse Oocytes
Published on: November 11, 2022
An intercellular pathway for glucose transport into mouse oocytes.
Qiang Wang1, Maggie M Chi, Tim Schedl
1State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China.
Summary
Glucose enters oocytes via cumulus cells using glucose transporters and gap junctions. This pathway influences oocyte quality in high-glucose conditions, impacting reproductive health.
Area of Science:
- Reproductive Biology
- Cellular Metabolism
- Mammalian Physiology
Background:
- Glucose is vital for mammalian cells and oocyte meiotic maturation.
- The mechanism of glucose entry into oocytes within cumulus-oocyte complexes (COCs) is debated.
Purpose of the Study:
- To investigate glucose transport into oocytes within COCs.
- To elucidate the roles of glucose transporters (GLUTs) and gap junctions in oocyte glucose uptake.
Main Methods:
- Utilized a fluorescent glucose derivative (6-NBDG) to track glucose in live mouse COCs.
- Employed GLUT inhibitors and gap junction blockers to assess their impact on glucose transport.
- Examined glucose uptake in both cumulus-enclosed and denuded oocytes.
Main Results:
- Fluorescent glucose entered both cumulus-enclosed and denuded oocytes.
- GLUT inhibitors reduced glucose uptake in cumulus cells and surrounding oocytes, but not denuded oocytes.
- Gap junction blockade significantly inhibited glucose transfer to oocytes.
- Hyperglycemic conditions increased oocyte glucose levels via gap junctions.
Conclusions:
- Glucose uptake by oocytes occurs through an intercellular pathway.
- Cumulus cells uptake glucose via GLUTs and transfer it to oocytes through gap junctions.
- This pathway may mediate the effects of hyperglycemia on oocyte quality and reproductive outcomes.
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