This study aimed at investigating the protective role of CoQ10
against cadmium (Cd)-induced reproductive toxicity in male rats.
Adult male Wistar rats were exposed to an acute dose of Cd
(25 mg/kg bwt; Cd group), Cd+CoQ10 (25 mg/kg bwt Cd+10 mg
CoQ10; Cd-Q10 group) and distilled water (control) in vivo for
15 consecutive days and semen quality was assessed.
A significant reduction was noted in sperm concentration,
progressive motility, morphology and DNA integrity in both Cdand Cd-Q10 groups in comparison to control indicating
Cd-induced testicular lipid per oxidation (LPO) and decline in
indigenous antioxidant defense system as measured by total
antioxidant capacity (TAC) (p<0.05). However, simultaneous
co-administration of CoQ10 along with Cd (Cd-Q10 group) was
able to improve sperm concentration, motility, progressive
motility, morphology, DNA integrity, and testicular TAC as well as
lower LPO compared to Cd group (p<0.05). Results indicate that
used dose of CoQ10 is capable of moderately ameliorating
reproductive toxicity of Cd by improving semen quality and
reducing testicular oxidative stress.
Natural and synthetic compounds called endocrine-disrupting chemicals can interfere with normal hormone binding to convey inaccurate signals or send mixed messages that may result in altered health outcomes of both wildlife and humans. Estriol is one of natural origin endocrine disruptors and it is metabolite of 17β-estradiol. The aim of this work was to develop a method for determining free estriol available to capaciting sperm. In order to determine a status of estriol during mouse sperm capacitation in vitro a high performance liquid chromatography HPLC method with UV detection was used. A free estriol, and the estriol bound to the bovine serum albumin in capacitation medium can be quantified by the proposed method. A reversed-phase separation mode using a SunFire C18 column with a simple mobile phase composed of acetonitrile and water, methanol and water at the ratio 40/60 (v/v) was applied. Our results show that the level of free estriol available for mouse spermatozoa during capacitation in vitro can be quantified by HPLC method with UV detection. Therefore, this method represents an important tool to determine the amount of environmental estrogens, such as estriol, bound to sperm cells at the specific time point of capacitation in vitro.
In humans, CD46 has been detected on the acrosomal membrane in sperm, in contrast to widespread surface expression on somatic cells where it plays a key role in the protection from complement attack. In rodents, CD46 is expressed solely on the acrosomal membrane of mature sperm and their immediate precursors, spermatids. A monoclonal antibody against the short consensus repeat (SCR1) ectodomain of CD46 blocks binding of human sperm to zona-free oocytes in vitro. However, CD46-knockout mice are fertile and have an accelerated spontaneous acrosome reaction. Wild-caught field mice (Apodemus) also exhibit a rapid acrosome reaction and CD46 is not expressed in Apodemus sperm. CD46 may, therefore, play a role in stabilization of the acrosomal membrane. Two other complement regulatory proteins, CD55 and CD59, are localized on the plasma membrane of mammalian sperm. In human sperm, CD55 and CD59 are expressed also on the inner acrosomal membrane. It remains to be clarified what is the role of CD46, CD55 and CD59 during fertilization and what are the advantages of not expressing CD46 in field mice sperm.
Spermatozoa of the monogenean Heterocotyle capricornensis Chisholm et Whittington, 1996 are long and filiform, comprising an elongate nucelus, probably a single elongate mitochondrion and two incorporated axonemes, one of which is shifted with respect to the other. The shift results in a region at each end of the sperm where only one axoncmc is present, accompanied by the nucleus and mitochondrion at one end and the nucleus and/or mitochondrion at the other. By taking note of the direction of dyncin arms on the axonemal doublet microtubules, each axoneme is identified and followed from beginning to end. No basal bodies remain in mature sperm but the main nuclear end is interpreted as proximal/anterior based on the final stages of spermiogenesis. A group of four or five cortical microtubules from the spermatid zone of differentiation persists in mature sperm, but is not closely associated with a region of extracellular matrix, as it is in other monocotylids. The sperm structure is compared with that of other monocotylids and the phylogenetic implications are discussed. Aberrant sperms in one individual were folded and fused along much of their length.