Voltage-dependent anion channels are a key factor of male fertility.
OBJECTIVE
To examine how voltage-dependent anion channels (VDACs) regulate sperm function in capacitation conditions.


METHODS
Experimental prospective study.


METHODS
Academic research laboratory.


METHODS
Male ICR and female B6D2F1/CrljOri mice (8-12 weeks old).


METHODS
Female mice were superovulated with 5 IU of pregnant mare serum gonadotropin given IP and 5 IU of hCG given IP 48 hours later. Oocytes were applied to assess fertilization and embryo development.


METHODS
Immunofluorescence assay, computer-assisted sperm analysis, hypo-osmotic swelling test, combined Hoechst 33258/chlortetracycline fluorescence assessment of capacitation status, measurement of [Ca(2+)](i) and [pH](i), Western blotting, and IVF.


RESULTS
VDAC2 was localized on the acrosomal region and principal piece, while VDAC3 was localized on the acrosomal region and midpiece. Blocking VDAC with DIDS (500 μM) significantly decreased motility, viability, acrosome reaction, capacitation, tyrosine phosphorylation, fertilization, and embryo development regardless of Ca(2+). However, the most severe decreases were observed in the presence (+) of DIDS and absence (-) of Ca(2+), respectively. A significant decrease in [Ca(2+)](i) concentration was observed in (-) DIDS, while [pH](i) was significantly increased in (-) DIDS regardless of Ca(2+). However, a significantly elevated [pH](i) was observed in (+) Ca(2+).


CONCLUSIONS
Abnormal regulation of VDACs negatively affected sperm function. Thus, VDACs may be key regulators of the fertilization ability of spermatozoa.
Department of Animal Science and Technology, School of Bioresource and Bioscience, Chung-Ang University, Anseong, South Korea.
Woo-Sung
WS
Kwon
Yoo-Jin
YJ
Park
El-Sayed A
el-SA
Mohamed
Myung-Geol
MG
Pang
D000177:Acrosome / Q000378:metabolism*; D000818:Animals; D005260:Female; D007248:Infertility, Male / Q000378:metabolism*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D033681:Mitochondrial Membrane Transport Proteins / Q000378:metabolism*; D013075:Sperm Capacitation; D050996:Voltage-Dependent Anion Channel 2 / Q000378:metabolism*; D050994:Voltage-Dependent Anion Channels / Q000378:metabolism*
D033681:Mitochondrial Membrane Transport Proteins; C494766:Vdac2 protein, mouse; C480078:Vdac3 protein, mouse; D050996:Voltage-Dependent Anion Channel 2; D050994:Voltage-Dependent Anion Channels