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Enrichment of Mammalian Tissues and Xenopus Oocytes with Cholesterol
Published on: March 25, 2020
Membrane fluidity changes in goat sperm induced by cholesterol depletion using beta-cyclodextrin
Mònica Companyó1, Antoni Iborra, Joaquim Villaverde
1Unitat de Biofísica, Departament de Bioquímica i de Biologia Molecular, Facultat de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
Biochimica Et Biophysica Acta
|August 3, 2007
Summary
Cholesterol removal from goat sperm membranes increases lipid microdomain fluidity before the acrosome reaction. This study used fluorescence anisotropy to track membrane changes, revealing insights into sperm capacitation.
Area of Science:
- Reproductive Biology
- Membrane Biophysics
- Sperm Physiology
Background:
- Cholesterol efflux from sperm membranes is known to initiate the acrosome reaction.
- The precise biophysical changes in sperm membranes following cholesterol removal remain incompletely understood.
Purpose of the Study:
- To investigate the impact of cholesterol removal on the fluidity of goat sperm membranes.
- To correlate changes in membrane lipid dynamics with the early stages of sperm capacitation.
Main Methods:
- Goat spermatozoa were incubated with beta-cyclodextrin to induce cholesterol efflux.
- Steady-state fluorescence anisotropy using 1,6-diphenyl-1,3,5-hexatriene (DPH) was employed to assess membrane fluidity.
- Thermotropic profiles of live sperm and sperm-derived liposomes were analyzed.
Main Results:
- Cholesterol removal significantly altered the thermotropic behavior of sperm membranes.
- Analysis revealed increased fluidity in specific lipid microdomains of the sperm membrane.
- Two distinct phase transitions were identified in whole sperm, affected by cholesterol depletion.
Conclusions:
- Cholesterol efflux induces biophysical changes in sperm membrane lipid dynamics prior to the acrosome reaction.
- Increased membrane fluidity in specific domains may be a critical early event facilitating sperm capacitation and the acrosome reaction.
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