Characterizing the Glycocalyx of Poultry Spermatozoa: II. In Vitro Storage of Turkey Semen and Mobility Phenotype Affects the Carbohydrate Component of Sperm Membrane Glycoconjugates

Abstract

The turkey sperm glycocalyx is known to contain residues of sialic acid, a-mannose/a-glucose, a-and b-galactose, afucose, a-and b-N-acetyl-galactosamine, monomers and dimers of N-acetyl-glucosamine, and N-acetyl-lactosamine. Potential changes in these carbohydrates during in vitro semen storage at 4uC were evaluated using males of both high-and low-sperm-mobility phenotypes. Changes in carbohydrate residues were quantified by flow cytometry analysis using a battery of 14 fluorescein isothiocyanate-labeled lectins in combination with control (sialylated) or neuraminidase-treated ( ). For nonsialylated sperm, increased binding of ECA, GS-II, SBA, and WFA was observed at variable time points; only Canavalia ensiformis lectin (Con A) and PSA remained unchanged during storage. Differences between mobility phenotypes existed for lectins Con A, GS-II, LFA, PSA, SBA, and sWGA, with sperm from lowmobility males exhibiting higher MnFI than high-mobility males throughout 24 hours of storage. We concluded that the observed increases in lectin binding during semen storage indicate an augmentation of nonsialylated terminal residues, which could alter sperm antigenicity and negatively impact fertility. Further, spermatozoa from low-mobility males may have higher antigenicity even before semen storage. Other possible functional implications are discussed.

A Common Mutation in the Defensin DEFB126 Causes Impaired Sperm Function and Subfertility

“…The dense carbohydrate coat provides protection for sperm during transit in the epididymis and female reproductive tract (8), and also assists with other key functions, including attachment of sperm to oviductal epithelium, regulation of capacitation, and sperm-egg interaction (9). Consistent with a proposed functional role of this sperm coat, differences in lectin labeling of the sperm glycocalyx between fertile and subfertile males have been detected in diverse species including fowl (10), livestock (11), and humans (12, 13) but the biochemical underpinnings of these observations remain elusive.…”

PHYSIOLOGY AND ENDOCRINOLOGY SYMPOSIUM: Role of the oviduct in maintaining sustained fertility in hens1

“…A local signal, possibly initiated by a component in seminal plasma or sperm, coupled with a response by the vaginal epithelial cells, may trigger a cascade of events that favor the adovarian transport of these sperm. Sperm signaling may be associated with the sperm plasmalemma glycoproteins, or lack of them (Bakst et al, 1994;Wishart and Horrocks, 2000;Peláez and Long, 2008). Rzas et al (1991) first demonstrated the presence of serotonin in the chicken oviduct.…”

Lectin Histochemistry as a Tool to Identify Apoptotic Cells in the Seminiferous Epithelium of Syrian Hamster (Mesocricetus auratus) Subjected to Short Photoperiod

“…Lectin histochemical techniques have been widely used to study the pattern of the glycoconjugates present in the cells of the seminiferous epithelium in many species of vertebrate, including amphibians (Valbuena et al 2010(Valbuena et al , 2011a, fish (Liguoro et al 2004;Desantis et al 2010), birds (Ballesta et al 1991;Bakst et al 2007;Pel aez and Long 2008), mammals (Arya and Vanha-Perttula 1985;Calvo et al 2000;Pinart et al 2001;Morales et al 2002;Desantis et al 2006;Parillo et al 2012) and humans (Arenas et al 1998). This histochemical technique has recently been used to identify changes in the pattern of glycoconjugates of various cell types in apoptosis (Taatjes et al 2008), in particular lectins with affinity for a-D-mannose and b-D-galactose (Bilyy et al 2004).…”