scholarly journals Mitochondrial activity and cytoskeleton organization in three pronuclei oocytes after intracytoplasmic sperm injection

Zygote ◽  
2018 ◽  
Vol 26 (4) ◽  
pp. 319-325
Author(s):  
Tuğba Kotil ◽  
M. Ertan Kervancıoğlu ◽  
Gülçin Ekter Kanten ◽  
Gülden Tunalı ◽  
Seyhun Solakoğlu

SummaryDigyny, the presence of a third pronucleus due to the failure of second polar body extrusion, is problematic after intracytoplasmic sperm injection (ICSI) practices. Mitochondria have critical roles such as production of adenosine triphosphate (ATP) and regulation of Ca2+ homeostasis during oocyte maturation, fertilization and the following development, while the regulation of meiotic spindle formation, chromosome segregation, pronuclear apposition and cytokinesis is closely associated with the cytoskeleton. In this study, mitochondrial membrane potential, distribution of F-actin and γ-tubulin, and the ultrastructure of three pronuclear (3PN) oocytes were investigated. 3PN oocytes after ICSI procedure were taken from patients who were enrolled in assisted reproduction programmes. For mitochondrial membrane potential analysis, fresh oocytes stained with the mitochondrial membrane potential probe JC-1, were evaluated under fluorescence microscopy. The mitochondrial membrane potential of three pronuclear oocytes showed similar results to normal zygotes. γ-Tubulin was stained strongly at the subplasmalemmal domain and microfilaments were localized at the cortical, but not the perinuclear, area. Cytoplasmic halos were moderately or not detected by electron microscopy; lipofuscin granules, degenerated mitochondria, and multilamellated bodies were seen in the ooplasm. Immunohistochemistry and electron microscopic findings suggested that mitochondrial membrane potential has no direct effect on second polar body extrusion. This abnormality can be associated with an altered cytoskeleton due to poor oocyte quality.

2019 ◽  
Vol 25 (11) ◽  
pp. 695-705 ◽  
Author(s):  
Usama AL-Zubaidi ◽  
Jun Liu ◽  
Ozgur Cinar ◽  
Rebecca L Robker ◽  
Deepak Adhikari ◽  
...  

Abstract Mitochondria are highly dynamic organelles and their distribution, structure and activity affect a wide range of cellular functions. Mitochondrial membrane potential (∆Ψm) is an indicator of mitochondrial activity and plays a major role in ATP production, redox balance, signaling and metabolism. Despite the absolute reliance of oocyte and early embryo development on mitochondrial function, there is little known about the spatial and temporal aspects of ΔΨm during oocyte maturation. The one exception is that previous findings using a ΔΨm indicator, JC-1, report that mitochondria in the cortex show a preferentially increased ΔΨm, relative to the rest of the cytoplasm. Using live-cell imaging and a new ratiometric approach for measuring ΔΨm in mouse oocytes, we find that ΔΨm increases through the time course of oocyte maturation and that mitochondria in the vicinity of the first meiotic spindle show an increase in ΔΨm, compared to other regions of the cytoplasm. We find no evidence for an elevated ΔΨm in the oocyte cortex. These findings suggest that mitochondrial activity is adaptive and responsive to the events of oocyte maturation at both a global and local level. In conclusion, we have provided a new approach to reliably measure ΔΨm that has shed new light onto the spatio-temporal regulation of mitochondrial function in oocytes and early embryos.


Author(s):  
Luukkonen Jukka ◽  
Höytö Anne ◽  
Sokka Miiko ◽  
Syväoja Juhani ◽  
Juutilainen Jukka ◽  
...  

AbstractIonizing radiation has been shown to cause induced genomic instability (IGI), which is defined as a persistently increased rate of genomic damage in the progeny of the exposed cells. In this study, IGI was investigated by exposing human SH-SY5Y neuroblastoma cells to hydroxyurea and zeocin, two chemicals mimicking different DNA-damaging effects of ionizing radiation. The aim was to explore whether IGI was associated with persistent mitochondrial dysfunction. Changes to mitochondrial function were assessed by analyzing mitochondrial superoxide production, mitochondrial membrane potential, and mitochondrial activity. The formation of micronuclei was used to determine immediate genetic damage and IGI. Measurements were performed either immediately, 8 days, or 15 days following exposure. Both hydroxyurea and zeocin increased mitochondrial superoxide production and affected mitochondrial activity immediately after exposure, and mitochondrial membrane potential was affected by zeocin, but no persistent changes in mitochondrial function were observed. IGI became manifested 15 days after exposure in hydroxyurea-exposed cells. In conclusion, immediate responses in mitochondrial function did not cause persistent dysfunction of mitochondria, and this dysfunction was not required for IGI in human neuroblastoma cells.


Reproduction ◽  
2008 ◽  
Vol 136 (2) ◽  
pp. 167-173 ◽  
Author(s):  
E Isachenko ◽  
V Isachenko ◽  
J M Weiss ◽  
R Kreienberg ◽  
I I Katkov ◽  
...  

This study investigates the ability of sucrose to protect spermatozoa against mitochondrial damage, artificial cryoinduction of capacitation, and acrosome reaction. Spermatozoa were isolated using the swim-up procedure performed using three different media: (a) human tubal fluid (HTF, control) medium; (b) HTF with 1% human serum albumin (HSA); and (c) HTF with 1% HSA and 0.25 M sucrose. From each group, 30 μl suspensions of cells were dropped directly into liquid nitrogen and stored for at least 24 h. Cells were thawed by quickly submerging the spheres in HTF with 1% HSA at 37 °C with gentle agitation. Sperm motility, viability, mitochondrial membrane potential integrity, spontaneous capacitation, and acrosome reaction were investigated. Sperm viability, acrosome reaction, and capacitation were detected using the double fluorescence chlortetracycline-Hoechst 33258 staining technique. Mitochondrial function was evaluated using a unique fluorescent cationic dye, 5,5′,6,6′-tetrachloro-1-1′,3,3′-tetraethyl-benzamidazolocarbocyanin iodide, commonly known as JC-1. The number of progressively motile spermatozoa was significantly higher in the sucrose-supplemented medium group (57.1±3.2%,P<0.05) when compared with controls (19.4±1.9%). The combination of HSA and sucrose (65.2±2.6%) has a stronger cryoprotective effect on the integrity of mitochondrial membrane potential (P<0.05) compared with HSA alone (32.6±4.7%). In conclusion, vitrification of human spermatozoa with non-permeable cryoprotectants such as HSA and sucrose can effectively cryopreserve the cells without significant loss of important physiological parameters.


Zygote ◽  
1998 ◽  
Vol 6 (2) ◽  
pp. 143-147 ◽  
Author(s):  
D. Dozortsev ◽  
T. Wakaiama ◽  
A. Ermilov ◽  
R. Yanagimachi

We applied intracytoplasmic sperm injection (ICSI) to the rat comparing three different sperm injection techniques: conventional setup with a sharp needle bearing a spike (method 1), combination of partial zona dissection (PZD) needle and blunt pipette (method 2) and piezo-injection using a blunt pipette (method 3). We also investigated the timing of sperm pronuclear formation after injection. Survival rates after injection were 8%, 24% and 71% for the methods 1, 2 and 3, respectively. All surviving oocytes formed pronuclei by about 6 h after injection. Although the survival and activation rates following sperm injection using piezo-injection were high, the incidence of normal fertilisation, as evidenced by second polar body extrusion and formation of two pronuclei, was only 10%. The vast majority of the zygotes were multinucleated, although most of them subsequently underwent cleavage. Fixation and staining of injected oocytes at different times after injection revealed that replacement of sperm nuclear protamines by histones takes place by 15 min after injection, sperm head swelling occurs within 0.5–1 h after injection and pronuclei become fully developed by 7 h after injection. Although the rate of normal fertilisation in the rat following ICSI was low under the present experimental conditions, the results indicated that direct ICSI using a piezo-driven pipette would be a potentially valuable method of producing rat offspring.


The Analyst ◽  
2015 ◽  
Vol 140 (17) ◽  
pp. 5849-5854 ◽  
Author(s):  
Lu Zhang ◽  
Wenwen Liu ◽  
Xianhong Huang ◽  
Guanxin Zhang ◽  
Xuefei Wang ◽  
...  

The tetraphenylethene-indolium molecule (TPE-indo) can both image the mitochondria and indicate mitochondrial activity by the fluorescence change of TPE-indo.


2020 ◽  
Author(s):  
Feng Wang ◽  
Ang Li ◽  
Tie-Gang Meng ◽  
Li-Juan Wang ◽  
Yi Hou ◽  
...  

Abstract Oocyte activation inefficiency is one of the reasons for female infertility and Ca 2+ functions play a critical role in the regulation of oocyte activation. We used various inhibitors of Ca 2+ channels and pumps located on the plasma membrane, the endoplasmic reticulum or both, including sarcoplasmic/endoplasmic reticulum Ca 2+ ATPases (SERCAs, the main Ca 2+ pumps which decrease the intracellular Ca 2+ level by reaccumulating Ca 2+ into the sarcoplasmic reticulum), transient receptor potential (TRP) ion channel subfamily member 7 (TRPM7, a Ca 2+ /Mg 2+ -permeable non-selective cation channel), T-type Ca 2+ channels and calcium channel Orai1, to investigate their roles in[Ca 2+ ] i oscillation patterns and mitochondrial membrane potential during oocyte activation by real-time recording. Our results show that SERCAs, TRPM7 and T-type Ca 2+ channels are important for initiation and maintenance of [Ca 2+ ] i oscillations, which is required for mitochondrial membrane potential changes during oocyte activation, as well as for subsequent pronuclear formation and transition to embryo development, while the function of calcium channel Orai1 is not confirmed. Increasing the knowledge of these transporters may provide a theoretical basis for improving oocyte activation in human assisted reproduction clinics.


2014 ◽  
Author(s):  
Yusuke Toyoda ◽  
Cihan Erkut ◽  
Francisco Pan-Montojo ◽  
Sebastian Boland ◽  
Martin P. Stewart ◽  
...  

Parkinson's disease is associated with mitochondrial decline in dopaminergic neurons of the substantia nigra. One of the genes, DJ- 1/PARK7, linked with the onset of Parkinson’s disease, belongs to a novel glyoxalase family and influences mitochondrial activity. It has been assumed that glyoxalases fulfill this task by detoxifying aggressive aldehyde by-products of metabolism. Here we show that supplying either D-lactate or glycolate, products of DJ-1, rescues the requirement for the enzyme in maintenance of mitochondrial potential. We further show that glycolic acid and D-lactic acid can elevate lowered mitochondrial membrane potential caused by silencing PINK-1, another Parkinson's related gene, as well as by paraquat, an environmental toxin known to be linked with Parkinson's disease. We propose that DJ-1 and consequently its products are components of a novel pathway that stabilizes mitochondria during cellular stress. We go on to show that survival of cultured mesencephalic dopaminergic neurons, defective in Parkinson's disease, is enhanced by glycolate and D-lactate. Because glycolic and D-lactic acids occur naturally, they are therefore a potential therapeutic route for treatment or prevention of Parkinson's disease.


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