Sperm motility

About: Sperm motility is a research topic. Over the lifetime, 13874 publications have been published within this topic receiving 416587 citations. The topic is also known as: sperm movement & GO:0097722.

Mammalian glutathione peroxidases control acquisition and maintenance of spermatozoa integrity

Abstract: In mammals, posttesticular epididymal sperm maturation is considered an essential step in the transformation of immature testicular gametes to mature spermatozoa capable of fertilization. Reactive oxygen species (ROS) have been shown to be key actors in this maturation process, and it is now clear that ROS are central for sperm physiology in processes such as sperm maturation and capacitation. However, during epididymal maturation and storage and until the onset of fertilization, oxidative damage is a threat spermatozoa must face more than any other cells. Spermatozoa were found to be extremely sensitive to oxidative attacks correlated with lipid peroxidation, DNA damage, and impaired sperm motility, all affecting fertilization. To control the quantity of H(2)O(2) in the vicinity of male gametes, mammalian epididymis uses a panel of nonenzymatic and enzymatic scavengers, among which the glutathione peroxidase (GPx) family is largely represented. Among the various GPx proteins expressed in the mammalian epididymis, GPx4 and GPx5 occupy unique positions and functions that are reviewed in this paper. This paper underlines the importance of the GPx protein family in determining the fertilizing potential of mammalian spermatozoa. This is particularly relevant in the field of mammalian fertility and infertility as well as in the development of assisted medical procreation technologies and male gamete preservation techniques that are extensively used in human and animal reproduction programs.

Characterization of the endocannabinoid system in human spermatozoa and involvement of transient receptor potential vanilloid 1 receptor in their fertilizing ability.

Abstract: Human spermatozoa express type-1 cannabinoid receptor (CB1), whose activation by anandamide (AEA) affects motility and acrosome reaction (AR). In this study, we extended the characterization of the AEA-related endocannabinoid system in human spermatozoa, and we focused on the involvement of the AEA-binding vanilloid receptor (TRPV1) in their fertilizing ability. Protein expression was revealed for CB1 ( approximately 56 kDa), TRPV1 ( approximately 95 kDa), AEA-synthesizing phospholipase D (NAPE-PLD) ( approximately 46 kDa), and AEA-hydrolyzing enzyme [fatty acid amide hydrolase (FAAH), approximately 66 kDa]. Both AEA-binding receptors (CB1 and TRPV1) exhibited a functional binding activity; enzymatic activity was demonstrated for NAPE-PLD, FAAH, and the purported endocannabinoid membrane transporter (EMT). Immunoreactivity for CB1, NAPE-PLD, and FAAH was localized in the postacrosomal region and in the midpiece, whereas for TRPV1, it was restricted to the postacrosomal region. Capsazepine (CPZ), a selective antagonist of TRPV1, inhibited progesterone (P)-enhanced sperm/oocyte fusion, as evaluated by the hamster egg penetration test. This inhibition was due to a reduction of the P-induced AR rate above the spontaneous AR rate, which was instead increased. The sperm exposure to OMDM-1, a specific inhibitor of EMT, prevented the promoting effect of CPZ on spontaneous AR rate and restored the sperm responsiveness to P. No significant effects could be observed on sperm motility. In conclusion, this study provides unprecedented evidence that human spermatozoa exhibit a completely functional endocannabinoid system related to AEA and that the AEA-binding TRPV1 receptor could be involved in the sperm fertilizing ability.

Changes in movement characteristics of human spermatozoa along the length of the epididymis.

Abstract: It has been established in laboratory mammals that sperm motility and fertilizing capacity develop during epididymal transit, but sperm maturation along the human epididymis is less well characterized. Spermatozoa were prepared from 5 regions of 8 epididymides from 8 prostatic carcinoma patients undergoing castration and from 8 epididymal spermatocoeles located adjacent to the head of the epididymides and the testes of 5 patients. Sperm movement was characterized by computer-aided sperm analysis (CASA), and percentage motility was estimated by conventional methods. The efferent ducts and spermatocoeles contained the same percentage of motile spermatozoa with similar kinematics. Percentage motility increased from 22.9 +/- 4.8 (mean +/- SEM) in the efferent ducts to a maximum of 68.3 +/- 7.9 in either the mid- or distal corpus epididymidis and declined in the cauda region. Straight line velocity increased from 20.3 +/- 3.7 microns/sec to reach a plateau value of 44.0 +/- 5.3 microns/sec in the mid-corpus epididymidis; this was more marked than the increase in curvilinear velocity, although the trend was the same. Similar trends in linearity and straightness of the swim paths were not accompanied by any significant changes in the amplitude of lateral head displacement. This objective quantification of sperm movement documents the maturation of sperm motility in the human epididymis, confirming that this maturation pattern is similar to that in other mammals.