Relationship of Aquaporin-3 and Aquaporin-7 with Cryotolerance of
Angus Bull Spermatozoa
Jiajia Suo1,2, Jieru Wang1, Qinghua Gao1*
and Ahrar Khan2**
1College
of Life Sciences, Tarim University, Alar, Xinjiang, China; 2Department
of Veterinary Medical Science, Shandong Vocational Animal Science
and Veterinary College, Weifang, Shandong, China.
*Corresponding authors:
gqhdky@126.com (*); ahrar1122@yahoo.com (**)
Abstract
Semen of all bulls is not suitable for freezing;
similarly, all ejaculates with excellent sperm vitality are not suitable for
freezing. Based on sperm survival at post-thawing, bull ejaculates are
categorized as good freezability ejaculates (GFE) and poor freezability
ejaculates (PFE). In this study, sperm quality parameters of GFE and PFE, with
the localization of aquaporin-3 (AQP-3) and aquaporin-7 (AQP-7) were
investigated. Moreover, the relationship of AQP-3 and AQP-7 with cryotolerance
of bull sperms was recorded. After fresh semen evaluation, 24 ejaculates from
four Angus bulls were cryopreserved and their sperm quality parameters were
analyzed by AndroVision before and after frozen-thawed. Expression of AQP-3 and
AQP-7 was determined through Western blot, while their localization was detected
by immunocytochemistry. The GFE and the PFE were well differentiated by sperm
motility, progressive motility, viability, acrosome integrity, and mitochondrial
activity, except for DNA integrity. AQP-3 was significantly higher in GFE than
PFE in frozen-thawed sperm, while the AQP-7 in fresh sperm of GFE was
significantly higher than that in fresh sperm of PFE and in frozen-thawed sperm
of GFE (P<0.05). The location of AQP-3 was seen in the sperm mid-piece, while
that of AQP-7 was recorded in the post-acrosome region, the mid and prime
tailpiece. In conclusion, GFE and PGE can be well distinguished by the
expression of AQP-7 in fresh semen, while AQP-7 could be a biomarker of sperm
cryotolerance in bull sperm. This study is hoped to improve the efficiency of
frozen sperm production and provide a reference for the improvement of frozen
semen production technology in other male animals, as well as humans.
To Cite This Article:
Suo J, Wang J, Gao Q and Khan A, 2023.
Relationship of aquaporin-3 and
aquaporin-7 with cryotolerance of angus bull spermatozoa. Pak Vet J, 43(4): 785-791. http://dx.doi.org/10.29261/pakvetj/2023.076