scholarly journals Impact of Cryopreservation on Motile Subpopulations and Tyrosine-Phosphorylated Regions of Ram Spermatozoa during Capacitating Conditions

Biology ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1213
Author(s):  
Patricia Peris-Frau ◽  
Irene Sánchez-Ajofrín ◽  
Alicia Martín Maestro ◽  
Carolina Maside ◽  
Daniela Alejandra Medina-Chávez ◽  
...  

The heterogeneous nature of ejaculates highlights the relevance of studying the behavior of different sperm subpopulations. Changes in sperm motility and the increase in tyrosine phosphorylation are key events that usually occur during capacitation and can be modified by the cryopreservation process. However, the relationship between both events remains poorly defined throughout capacitation in the different sperm subpopulations. Fresh and frozen-thawed spermatozoa were incubated in capacitating (CAP) and non-capacitating (NC) media up to 240 min. Sperm kinematics, tyrosine phosphorylation and mitochondrial activity were measured by the CASA system and imaging flow cytometry. Four motile sperm subpopulations (SP) were identified in fresh and frozen-thawed ram semen after the cluster analysis. Incubation under CAP conditions over time led to greater changes in the percentage of spermatozoa included in each subpopulation compared to NC conditions, being different between fresh and frozen-thawed spermatozoa. The SP1, characterized by slow spermatozoa, progressively increased after 15 min in frozen-thawed samples incubated in both media but not in fresh ones. The SP4, characterized by fast and non-linear spermatozoa, showed a marked increase during CAP, but not under NC conditions, occurring more rapidly in frozen-thawed spermatozoa. This subpopulation (SP4) was also the only one positively and strongly correlated with mitochondrial activity and all phosphorylated sperm regions during capacitation, either in fresh or frozen-thawed samples. Our results indicated that in vitro capacitation induced significant changes in the distribution of motile sperm subpopulations, being affected by cryopreservation. Notwithstanding, the subpopulation which probably represents hyperactivated-like spermatozoa (SP4) also increased in frozen-thawed samples, occurring faster and simultaneously to the increment of mitochondrial activity and tyrosine phosphorylation of different sperm regions.

2019 ◽  
Vol 5 (11) ◽  
pp. eaax8849 ◽  
Author(s):  
Akira Yokoi ◽  
Alejandro Villar-Prados ◽  
Paul Allen Oliphint ◽  
Jianhua Zhang ◽  
Xingzhi Song ◽  
...  

Exosome cargoes are highly varied and include proteins, small RNAs, and genomic DNA (gDNA). The presence of gDNA suggests that different intracellular compartments contribute to exosome loading, resulting in distinct exosome subpopulations. However, the loading of gDNA and other nuclear contents into exosomes (nExo) remains poorly understood. Here, we identify the relationship between cancer cell micronuclei (MN), which are markers of genomic instability, and nExo formation. Imaging flow cytometry analyses reveal that 10% of exosomes derived from cancer cells and <1% of exosomes derived from blood and ascites from patients with ovarian cancer carry nuclear contents. Treatment with genotoxic drugs resulted in increased MN and nExos both in vitro and in vivo. We observed that multivesicular body precursors and exosomal markers, such as the tetraspanins, directly interact with MN. Collectively, this work provides new insights related to nExos, which have implications for cancer biomarker development.


2020 ◽  
Vol 32 (6) ◽  
pp. 629
Author(s):  
Xinyi Sun ◽  
Wenqiong Chen ◽  
Shiqi Weng ◽  
Tingting Pan ◽  
Xiaonian Hu ◽  
...  

Di-2-ethylhexyl phthalate (DEHP), a plastic-derived, endocrine-disrupting chemical, has been shown to exhibit male reproductive toxicity. However, its effects on human mature spermatozoa are largely unknown. In this study we investigated the invitro effects of DEHP and mono-2-ethylhexyl phthalate (MEHP; the main metabolite of DEHP) on sperm function and the mechanisms involved. Human spermatozoa were exposed to phthalates invitro at the doses that cover the concentrations detected in human semen: 20nM–8 μM DEHP, 1nM–20 μM MEHP or a mixture of 20nM–8 μM DEHP and 1nM–20 μM MEHP. DEHP and MEHP, alone or in combination, had no effect on the viability, membrane integrity, motility, homeostasis of reactive oxygen species or mitochondrial activity of human spermatozoa. Interestingly, 1nM–20 μM MEHP and combinations of 20nM–8 μM DEHP and 1nM–20 μM MEHP enhanced penetration ability, hyperactivation and the spontaneous acrosome reaction of human spermatozoa, and increased intracellular free Ca2+ concentrations ([Ca2+]i) and tyrosine phosphorylation, two key signalling pathways that regulate sperm function. The findings of this study suggest that invitro exposure to MEHP metabolised from DEHP affects human sperm function by inducing increases in sperm [Ca2+]i and tyrosine phosphorylation, which adds to our understanding of the effects of DEHP on male reproduction.


2021 ◽  
pp. 1-9
Author(s):  
Paula Sáez-Espinosa ◽  
Alba López-Huedo ◽  
Laura Robles-Gómez ◽  
Natalia Huerta-Retamal ◽  
Jon Aizpurua ◽  
...  

Spermatozoa capacitation is a time-dependent physiological process essential for acquiring the fertilizing capacity. In this context, reorganization of spermatozoa surface sugars and tyrosine phosphorylation are some of the most important biochemical changes involved in capacitation. However, the relationship between these 2 biomarkers remains poorly defined. By cytofluorescence we simultaneously characterized the head concanavalin A (ConA)-binding sites and the flagellar tyrosine phosphorylation before capacitation, during different capacitation times (1 and 4 h), and after acrosome reaction induction in human spermatozoa. The results showed a strong connection between ConA-label patterns and tyrosine phosphorylation according to the spermatozoa capacitation time and acrosomal status. Specifically, the spermatozoa subpopulation with phosphotyrosine presented proper sugar location (label in acrosomal and postacrosomal region) just after 1 h of capacitation, while cells without phosphotyrosine needed 4 h to do it. Moreover, after induction of spermatozoa acrosome reaction, phosphorylation was significantly correlated (<i>p</i> &#x3c; 0.05) with the relocation of ConA-binding residues to the equatorial region, regardless of capacitation time. Overall, these observations provide novel insights regarding spermatozoa subpopulations based on essential physiological events like capacitation and acrosome reaction, which could have potential implications in the improvement of spermatozoa selection techniques.


2020 ◽  
Vol 21 (12) ◽  
pp. 4520
Author(s):  
Ana Paula Pinoti Pavaneli ◽  
Sandra Recuero ◽  
Bruna Resende Chaves ◽  
Estela Garcia-Bonavila ◽  
Marc Llavanera ◽  
...  

Although seminal plasma is essential to maintain sperm integrity and function, it is diluted/removed prior to liquid storage and cryopreservation in most mammalian species. This study sought to evaluate, using the pig as a model, whether storing semen in the presence of seminal plasma affects the sperm ability to elicit in vitro capacitation and acrosomal exocytosis. Upon collection, seminal plasma was separated from sperm samples, which were diluted in a commercial extender, added with seminal plasma (15% or 30%), and stored at 17 °C for 48 or 72 h. Sperm cells were subsequently exposed to capacitating medium for 4 h, and then added with progesterone to induce acrosomal exocytosis. Sperm motility, acrosome integrity, membrane lipid disorder, intracellular Ca2+ levels, mitochondrial activity, and tyrosine phosphorylation levels of glycogen synthase kinase-3 (GSK3)α/β were determined after 0, 2, and 4 h of incubation, and after 5, 30, and 60 min of progesterone addition. Results showed that storing sperm at 17 °C with 15% or 30% seminal plasma led to reduced percentages of viable spermatozoa exhibiting an exocytosed acrosome, mitochondrial membrane potential, intracellular Ca2+ levels stained by Fluo3, and tyrosine phosphorylation levels of GSK3α/β after in vitro capacitation and progesterone-induced acrosomal exocytosis. Therefore, the direct contact between spermatozoa and seminal plasma during liquid storage at 17 °C modulated their ability to elicit in vitro capacitation and undergo acrosomal exocytosis, via signal transduction pathways involving Ca2+ and Tyr phosphorylation of GSK3α/β. Further research is required to address whether such a modulating effect has any impact upon sperm fertilizing ability.


1993 ◽  
Vol 41 (8) ◽  
pp. 1247-1251 ◽  
Author(s):  
J Auger ◽  
S Leonce ◽  
P Jouannet ◽  
X Ronot

We investigated the applicability of flow cytometric (FCM) sorting to select, with no deleterious effects, fractions of living, highly motile spermatozoa after staining with rhodamine 123 (Rh123) and propidium iodide (PI) for assessment of their mitochondrial activity and viability, respectively. Sperm cells were subjected to FCM sorting according to their Rh123 fluorescence intensity, and computer-aided sperm analysis (CASA) for percentage motility and movement characteristic measurements was carried out on the entire sperm populations and on the Rh123-positive (Rh123+) sorted fractions. A first experiment on five sperm samples from fertile donors pre-selected by either swim-up or simplified Percoll gradient indicated no detrimental effect of the FCM sorting procedure because: (a) the numbers of Rh123+ motile sperm were not decreased by FCM sorting; (b) data on the sorted fractions showed a tendency (not significant) for an increase in movement parameters rather than a drop; and (c) a significant decrease in the percentage of PI-positive (PI+) sperm (13% vs 3%; p < 0.05) was measured. A second experiment was performed on sperm samples from four patients, only washed and re-suspended in B2 medium. This demonstrated a significant increase in some characteristics of movement quality related to a substantial and selective immobilization of the less motile sperm. The significant drop in the percentage of PI+ sperm after FCM sorting (p < 0.01) was less pronounced than after FCM sorting of pre-selected sperm (12% vs 3%, respectively), indicating a lethal effect of FCM sorting on a small proportion of presumably moribund sperm. These preliminary data indicate a differential effect of FCM sorting on sperm according to their function characteristics and suggest the potential importance of these methods for the characterization in vitro of sperm subpopulations on the basis of functional criteria.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Kinga A. Kocemba-Pilarczyk ◽  
Paulina Dudzik ◽  
Katarzyna Leśkiewicz

Abstract Objectives CD146 is an adhesive molecule that was originally reported on malignant melanoma cells as a protein crucial for cell adhesion. It is now known that high expression of the CD146 protein is not only characteristic of melanoma, but it occurs on a number of cancers, contributing to worse prognosis and increased aggressiveness. Independent in vitro studies in breast cancer have shown that CD146 protein alone can induce a change in epithelial to mesenchymal transcriptional profile, which is the basis of the tumor aggressiveness and metastasis. Methods In the following work, the correlation coefficients were analyzed between the genes of the mesenchymal profile and the CD146 gene in 10 independent transcriptomic data of breast cancer patients. Results The analysis confirmed the relationship between CD146 expression and mesenchymal profile genes, pointing VIMENTIN as the gene which expression is most strongly correlated with the CD146, suggesting that both genes, CD146 and VIM may be directly controlled by the same mechanism or regulate one another. Conclusions The analysis points a potential route for research on the CD146 gene expression, which may lead to understanding of its regulation in breast cancer, contributing to the development of new therapeutic strategies targeting highly metastatic breast cancer cells.


Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.


1993 ◽  
Vol 70 (06) ◽  
pp. 0998-1004 ◽  
Author(s):  
Páll T Önundarson ◽  
H Magnús Haraldsson ◽  
Lena Bergmann ◽  
Charles W Francis ◽  
Victor J Marder

SummaryThe relationship between lytic state variables and ex vivo clot lysability was investigated in blood drawn from patients during streptokinase administration for acute myocardial infarction. A lytic state was already evident after 5 min of treatment and after 20 min the plasminogen concentration had decreased to 24%, antiplasmin to 7% and fibrinogen 0.2 g/1. Lysis of radiolabeled retracted clots in the patient plasmas decreased from 37 ± 8% after 5 min to 21 ± 8% at 10 min and was significantly lower (8 ± 9%, p <0.005) in samples drawn at 20, 40 and 80 min. Clot lysability correlated positively with the plasminogen concentration (r = 0.78, p = 0.003), but not with plasmin activity. Suspension of radiolabeled clots in normal plasma pre-exposed to 250 U/ml two-chain urokinase for varying time to induce an in vitro lytic state was also associated with decreasing clot lysability in direct proportion with the duration of prior plasma exposure to urokinase. The decreased lysability correlated with the time-dependent reduction in plasminogen concentration (r = 0.88, p <0.0005). Thus, clot lysability decreases in conjunction with the development of the lytic state and the associated plasminogen depletion. The lytic state may therefore limit reperfusion during thrombolytic treatment.


1994 ◽  
Vol 72 (05) ◽  
pp. 685-692 ◽  
Author(s):  
Michael T Nurmohamed ◽  
René J Berckmans ◽  
Willy M Morriën-Salomons ◽  
Fenny Berends ◽  
Daan W Hommes ◽  
...  

SummaryBackground. Recombinant hirudin (RH) is a new anticoagulant for prophylaxis and treatment of venous and arterial thrombosis. To which extent the activated partial thromboplastin time (APTT) is suitable for monitoring of RH has not been properly evaluated. Recently, a capillary whole blood device was developed for bed-side monitoring of the APTT and it was demonstrated that this device was suitable to monitor heparin therapy. However, monitoring of RH was not evaluated.Study Objectives. To evaluate in vitro and ex vivo the responsiveness and reproducibility for hirudin monitoring of the whole blood monitor and of plasma APTT assays, which were performed with several reagents and two conventional coagulometers.Results. Large interindividual differences in hirudin responsiveness were noted in both the in vitro and the ex vivo experiments. The relationship between the APTT, expressed as clotting time or ratio of initial and prolonged APTT, and the hirudin concentration was nonlinear. A 1.5-fold increase of the clotting times was obtained at 150-200 ng/ml plasma. However, only a 2-fold increase was obtained at hirudin levels varying from 300 ng to more than 750 ng RH/ml plasma regardless of the assays. The relationship linearized upon logarithmic conversion of the ratio and the hirudin concentration. Disregarding the interindividual differences, and presuming full linearity of the relationship, all combinations were equally responsive to hirudin.Conclusions. All assays were equally responsive to hirudin. Levels up to 300 ng/ml plasma can be reliably estimated with each assay. The manual device may be preferable in situations where rapid availability of test results is necessary.


GYNECOLOGY ◽  
2018 ◽  
Vol 20 (1) ◽  
pp. 113-116
Author(s):  
L A Bagdasaryan ◽  
I E Korneyeva

The aim of the study is to systematically analyze the data available in the modern literature on the relationship between endometrial thickness and the frequency of pregnancy in the program of assisted reproductive technologies (ART). Materials and methods. The review includes data from foreign and domestic articles found in PubMed on this topic. Results. The article presents data on the relationship between the thickness of the endometrium and the frequency of pregnancy in ART programs. The greatest number of studies is devoted to the evaluation of the relationship between the thickness of the endometrium and the frequency of pregnancy on the day of the ovulation trigger. Data are presented on the existence of a correlation between the thickness of the endometrium measured on the day of the ovulation trigger and the frequency of clinical pregnancy, as well as data on the need to evaluate the structure of the endometrium and the state of subendometric blood flow. The importance of multilayered (three-layered) endometrium as a prognostic marker of success in in vitro fertilization/intracytoplasmic sperm injection programs in the ovum is emphasized. The conclusion. The thickness of the endometrium can not be used as an argument for canceling the cycle or abolishing embryo transfer to the uterine cavity. Further studies in this direction are needed with a study of the morphological and molecular genetic characteristics of the endometrium, which in the future will allow us to evaluate the relationship between the thickness of the endometrium and the probability of pregnancy.


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