Aquaporins 7 and 11 in boar spermatozoa: detection, localisation and relationship with sperm quality

Abstract

Aquaporins (AQPs) are integral membrane water channels that allow transport of water and small solutes across cell membranes. Although water permeability is known to play a critical role in mammalian cells, including spermatozoa, little is known about their localisation in boar spermatozoa. Two aquaporins, AQP7 and AQP11, in boar spermatozoa were identified by western blotting and localised through immunocytochemistry analyses. Western blot results showed that boar spermatozoa expressed AQP7 (25kDa) and AQP11 (50kDa). Immunocytochemistry analyses demonstrated that AQP7 was localised in the connecting piece of boar spermatozoa, while AQP11 was found in the head and mid-piece and diffuse labelling was also seen along the tail. Despite differences in AQP7 and AQP11 content between boar ejaculates, these differences were not found to be correlated with sperm quality in the case of AQP7. Conversely, AQP11 content showed a significant correlation (P<0.05) with sperm membrane integrity and fluidity and sperm motility. In conclusion, boar spermatozoa express AQP7 and AQP11, and the amounts of AQP11 but not those of AQP7 are correlated with sperm motility and membrane integrity.

Aquaporins in the male reproductive tract and sperm: Functional implications and cryobiology

“…On the other hand, AQP7 staining has been reported to change in response to sperm cryopreservation in boars but not in bulls (Prieto‐Martínez, Morató et al., ; Prieto‐Martínez, Vilagran et al., ; Prieto‐Martínez et al., ). Indeed, while Prieto‐Martínez, Vilagran et al.…”

New insights into transduction pathways that regulate boar sperm function

“…Recently, it has been reported the presence of integral membrane water channels, aquaporins 7 and 11 in boar sperm. The amount of aquaporin 11 shows a correlation with sperm motility and membrane integrity [7].…”

Membrane Stress During Thawing Elicits Redistribution of Aquaporin 7 But Not of Aquaporin 9 in Boar Spermatozoa

“…As well, AQP-7 has been found in human spermatozoa (Moretti et al 2011) and in the seminiferous epithelium, suggested as associated with volume regulation in germ cells ). AQP-7 has been immunocytochemically (ICC) detected in boar spermatozoa using different commercial antibodies (Prieto-Mart ınez et al 2014;Vicente-Carrillo 2015) and its role related to sperm quality (Prieto-Mart ınez et al 2014) and/or capacity to react under different osmotic pressures (Vicente-Carrillo 2015). The ICC of the above studies depicted different localization of AQP-7, perhaps due to differences in the specificity of the antibodies used, a matter for reported concern regarding AQPs (Yeung 2010).…”

“…Presumably, this AQP-7 would also provide a port for glycerol as a carbon source for mature sperm metabolism. AQP-7 has been immunocytochemically (ICC) detected in boar spermatozoa using different commercial antibodies [17][18] and its role related to sperm quality 18 and/or capacity to react under different osmotic pressures 17 . The ICC of the above studies depicted different localization of AQP-7, perhaps due to differences in the specificity of the antibodies used, a matter for reported concern regarding AQPs…”