Mammalian sperm capacitation and fertilization in vitro: A critique of methodology

1978 ◽  
Vol 1 (2) ◽  
pp. 165-223 ◽  
Author(s):  
B. Jane Rogers
1991 ◽  
Vol 14 (4) ◽  
pp. 283-290 ◽  
Author(s):  
P. PIYACHATURAWAT ◽  
W. SRIWATTANA ◽  
P. DAMRONGPHOL ◽  
C. PHOLPRAMOOL

Author(s):  
Sara Miguel-Jiménez ◽  
Blanca Pina-Beltrán ◽  
Silvia Gimeno-Martos ◽  
Melissa Carvajal-Serna ◽  
Adriana Casao ◽  
...  

Reactive oxygen species (ROS) play an essential role in mammalian sperm capacitation. NADPH oxidase 5 (NOX5) has been described as the main source of ROS production in some mammalian spermatozoa, such as human and equine. On the other hand, melatonin can decrease cellular ROS levels and regulates NOX activity in somatic cells. Therefore, the objectives of this work were (1) to identify NOX5 in ram spermatozoa and analyze its possible changes during in vitro capacitation and (2) to investigate the effect of melatonin on NOX5 expression and localization and on superoxide levels in capacitated ram spermatozoa. Protein bands associated with NOX5 were detected by Western blot analysis. Likewise, indirect immunofluorescence (IIF) revealed six different immunotypes for NOX5, which varied throughout in vitro capacitation. Superoxide (O2⋅–), evaluated by DHE/Yo-Pro-1, rose after in vitro capacitation and in the presence of the calcium ionophore A23187 but decreased in the presence of the NOX inhibitor GKT136901. GKT also reduced the percentage of capacitated and acrosome-reacted spermatozoa that had increased during incubation in capacitating conditions. The presence of melatonin at micromolar concentrations avoided the increment in O2⋅– and the changes in NOX5 immunotypes provoked by capacitation. In conclusion, NOX5 is present in ram spermatozoa and the changes in its distribution, associated with sperm capacitation, can be prevented by melatonin. To this extent, it could imply that melatonin exerts its antioxidant role, at least in part, by modulating NOX5 activity during ram sperm capacitation.


Reproduction ◽  
2000 ◽  
pp. 127-135 ◽  
Author(s):  
W Bone ◽  
NG Jones ◽  
G Kamp ◽  
CH Yeung ◽  
TG Cooper

The effects of the male antifertility agent ornidazole on glycolysis as a prerequisite for fertilization were investigated in rats. Antifertility doses of ornidazole inhibited glycolysis within mature spermatozoa as determined from the lack of glucose utilization, reduced acidosis under anaerobic conditions and reduced glycolytic enzyme activity. As a consequence, cauda epididymidal spermatozoa from ornidazole-fed rats were unable to fertilize rat oocytes in vitro, with or without cumulus cells, which was not due to transfer of an inhibitor in epididymal fluid with the spermatozoa. Under IVF conditions, binding to the zona pellucida was reduced in spermatozoa from ornidazole-fed males and the spermatozoa did not undergo a change in swimming pattern, which was observed in controls. The block to fertilization could be explained by the disruption of glycolysis-dependent events, since reduced binding to the zona pellucida and a lack of kinematic changes were demonstrated by control spermatozoa in glucose-free media in the presence of respiratory substrates. The importance of glycolysis for binding to, and penetration of, the zona pellucida, and hyperactivation in rats is discussed in relation to the glycolytic production of ATP in the principal piece in which local deprivation of energy may explain the reduced force of spermatozoa from ornidazole-fed males.


2016 ◽  
pp. 140-143
Author(s):  
N.V. Cotsabin ◽  
◽  
O.M. Makarchuk ◽  

The proportion of patients with multiple unsuccessful attempts of assisted reproductive technology (ART) is about 30% of all patients treated with the use of ART. Women with history of unsuccessful ART attempts - a special category of patients who require emergency attention and a thorough examination at the stage of preparation for superovulation stimulation,the selection of embryos and endometrium preparation for embryo transfer. The objective: to distinguish high-risk group of unsuccessful attempts based on a detailed analysis of anamnestic and clinical data of infertile women with repeated unsuccessful ART attempts that requires more in-depth study of hormonal features, ovarian reserve and condition of the endometrium. Materials and methods. For better understanding of the problem of repeated unsuccessful ART attempts and сreation of efficient infertility treatment algorithms for these couples we conducted a thorough analysis of anamnestic data of three groups of infertile women (105 patients), which were distributed by age: group I – younger than 35, the II group – from 35 to 40, the III group - over 40 years. These groups of patients were compared with each other and with the control group of healthy women (30 persons). Results. Leading stress factors in the percentage three times prevailed in the group of infertile women and had a direct connection with the fact of procedure «fertilization in vitro» and chronic stressors caused by prolonged infertility. Primary infertility was observed significantly more frequent in patients younger than 35 years (p <0.05), secondary infertility - mostly in the second and third experimental groups (p <0.05). Noteworthy significant percentage of wellknown causes of infertility and idiopathic factor in all groups, and the prevalence of tubal-peritoneal factor in the second and third experimental groups, and endocrine dysfunction in the I experimental group. The most common disorder among this category of woman was polycystic ovary syndrome. Frequency of usual miscarriage among patients of I ana II groups was two times higher than in the third group (p <0.05). Among the experimental groups the leading place belongs urinary tract infection, respiratory tract diseases, pathologies of the cardiovascular system. Data of the stratified analysis show an increase likelihood of repeated unsuccessful ART attempts under the influence of constant chronic stress (odds ratio OR=2.06; 95% CI: 0.95–3.17; p<0.05). Conclusions. Among infertile patients with repeated unsuccessful ART attempts must be separated a high risk group of failures. The identity depends on the duration of infertility, female age and leading combination of factors. Key words: repeated unsuccessful ART attempts, anamnesis, infertility, high risk.


2013 ◽  
Vol 16 (3) ◽  
pp. 593-599 ◽  
Author(s):  
J. Opiela ◽  
M. Samiec

Abstract The efficiency of somatic cell cloning (somatic cell nuclear transfer; SCNT) as well as in vitro fertilization/in vitro embryo production (IVF/IVP) in mammals stay at relatively same level for over a decade. Despite plenty of different approaches none satisfactory break-through took place. In this article, we briefly summarize the implementation of mesenchymal stem cells (MSCs) for experimental embryology. The advantages of using MSCs as nuclear donors in somatic cell cloning and in vitro embryo culture are described. The description of results obtained with these cells in mammalian embryo genomic engineering is presented.


Reproduction ◽  
1992 ◽  
Vol 95 (2) ◽  
pp. 431-440 ◽  
Author(s):  
Y. Hatanaka ◽  
T. Nagai ◽  
T. Tobita ◽  
M. Nakano

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