Short communication. Evaluation of a commercial kit based on acridine orange/propidium iodide to assess the plasma membrane integrity of ram sperm

The spermatozoa is an ideal vehicle for genetic modification, production of transgenic animals, as well as a biotechnological tool for sperm-mediated gene transfer. However, in order to achieve successful sperm fertilization and exogenous DNA integration, it is necessary for viable cells to remain intact, allowing the sperm to penetrate the oocyte. Fluorescent probes allow evaluation of morphological and functional characteristics of cells, which can be evaluated separately or simultaneously. Therefore, the aim of this study was to validate the simultaneous evaluation of the integrity of plasma and acrosomal membranes of murine sperm using the probes carboxyfluorescein diacetate (CF) and propidium iodide (PI). In order to validate, a standard curve was performed. Sperm were obtained from epididymis and vas deferens from CD-1 mice (8 to 16 weeks of age). Recovered samples were diluted in PBS and then divided into 2 aliquots: one prepared with fresh semen (FS) and the other submitted to Percoll gradient (45%/90%) followed by flash-freezing in liquid nitrogen and thawing (FTP) to induce acrosome damage. Samples were prepared with the following average of FS:FTP: 100:0 (T100), 50 : 50 (T50), and 0 : 100 (T0). Samples were stained using 2 μL Hoescht 33342 (40 μLmL-1 in Dulbecco’s phosphate buffered saline), 3 μL of PI (0.5 mg mL-1 in PBS), 3 μL of CF (0.46 mg mL-1 in DMSO), and were incubated for 8 min at room temperature. After staining, the samples were placed on a slide, coverslipped, and evaluated immediately by epifluorescent microscopy. The Hoescht, PI, and CF fluorescence was detected using a filter with excitation at 352, 538, and 495 nm and emission at 455, 617, and 517 nm, respectively. Approximately 200 sperm cells per slide were examined and classified based on the fluorescence emitted from each probe. Spermatozoa CF+/IP- were considered as intact membranes, CF+/PI+ as acrosome membrane intact and plasma damaged, CF-/PI+ as damaged membranes, and CF-/PI- as acrosome membrane damaged and plasma intact. Hoeschst was used as positive dye. This experiment was replicated 6 times per group, and for statistical analyses, the data of plasma and acrosomal membrane integrity (dependent variables) in the treatments T0, T50, and T100 (independent variables) were submitted to simple linear regression analysis by STATVIEW software (SAS Institute Inc., Cary, NC, USA). The CFDA/PI probes were suitable for the analysis of acrosomal and membrane status of murine sperm and showed a high determination coefficient to plasma membrane integrity (R2 = 0.81; Y = 0.5412x + 6.375) and acrosome integrity (R2 = 0.85; Y = 0.5653x + 11.653). The described protocol was efficient for the simultaneous evaluation of plasma and acrosomal membrane integrity of murine spermatozoa, proving that CFDA can be employed to access acrosomal integrity as an alternative to FITC-PSA. Financial support: FAPESP.

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34 Cellular effects of antifreeze proteins type I and III in extender for sheep semen cryopreservation

Reproduction Fertility and Development ◽

10.1071/rdv33n2ab34 ◽

2021 ◽

Vol 33 (2) ◽

pp. 124

Author(s):

L. F. L. Correia ◽

C. G. Espírito-Santo ◽

R. F. Braga ◽

V. L. Brair ◽

C. J. C. de Paula ◽

...

Keyword(s):

Plasma Membrane ◽

Chromatin Condensation ◽

Antifreeze Proteins ◽

Membrane Integrity ◽

Mitochondrial Activity ◽

Type I ◽

Plasma Membrane Integrity ◽

Ram Sperm ◽

Perivitelline Membrane ◽

Normally Distributed

Antifreeze proteins (AFP) have been included in extenders for sperm cryopreservation to prevent ice crystal formation. Thus, this study assessed the effects of supplementing semen extender with two concentrations of AFP types I and III on the quality of frozen–thawed ram sperm. The hypothesis is that various types and concentrations of AFP enhance cryopreservation of ram sperm. Semen was collected from 4 rams, pooled in 6 replicates, and allocated into 1 of 5 treatments: Control (CONT, without AFP); AFP type I [0.1 (AFPI-0.1) or 0.5 (AFPI-0.5) µg±mL−1]; or AFP type III [0.1 (AFPIII-0.1) or 0.5 (AFPIII-0.5) µg±mL−1]. Straws were placed on a metal wire net frame at 37°C and placed in a refrigerator for 2h to cool them to 5°C (−0.25°C/min). After 2h for stabilisation, straws were cooled in liquid nitrogen vapor (−15.3°C/min) and subsequently immersed (−196°C). After thawing, samples from each treatment were evaluated microscopically (sperm kinetics, plasma membrane integrity, capacitation, hypoosmotic test, acrosome status and mitochondrial activity, chromatin condensation, morphology, binding to egg perivitelline membrane, and lipoperoxidation quantification). The normal distribution of residuals was determined by Shapiro-Wilk test and homoscedasticity by Levene’s test. Normally distributed variables were analysed with one-way analysis of variance (ANOVA), followed by Tukey’s test. The non-normally distributed were analysed by Kruskal–Wallis and Dunn’s test. The repeated-measures ANOVA in general linear model (GLM) was used to effects of concentration for each AFP type in paired samples. The Greenhouse-Geisser test was applied when sphericity was not considered, followed by the Sidak test. Values of P<0.05 were considered significant. Treatments affected (P<0.05) kinetic parameters, plasma membrane integrity, and morphology. Linearity was greater in AFPI-0.1 (56.6±3.1%, mean±s.e.m.), AFPI-0.5 (56.9±2.2%), and AFPIII-0.5 (64.7±6.2%) than in CONT (36.8±3.0%). Straightness was greater in all AFP-supplemented extenders (overall mean, 78.6±2.8%) than in CONT (63.2±0.8%). Plasma membrane integrity was greater in AFPI-0.1 (49.1±4.6%) and AFPI-0.5 (36.6±7.3%) compared with CONT (13.0±4.4%). All AFP groups had a greater percentage of normal sperm (overall mean: 74.3±1.3%) than CONT (65.3±1.9%). There were no significant differences in percentage of sperm with functional membrane (overall mean: 16.1±3.3%), normal acrosome (11.5±4.5%), mitochondrial activity (24.5±6.5%), chromatin condensation (98.8±0.4%), perivitelline membrane binding rate (194.0±44.5 sperm/mm2), and lipoperoxidation (556.7±20.5 TBARS ng±mL−1). In conclusion, the use of AFP, predominantly type I, had potential as a cryoprotectant for ram sperm, increasing sperm cell protection, with no adverse effects on potential fertilization capacity and did not increase reactive oxygen species. This research was funded by FAPERJ, CNPq, and CAPES (Finance Code 001).

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Assessment of Sperm Plasma Membrane Integrity and Viability: Propidium Iodide/SYBR-14

Equine Reproductive Procedures ◽

10.1002/9781118904398.ch145 ◽

2014 ◽

pp. 476-477

Author(s):

Amanda I. Glazar

Keyword(s):

Plasma Membrane ◽

Propidium Iodide ◽

Membrane Integrity ◽

Plasma Membrane Integrity ◽

Sperm Plasma Membrane

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Phosphate efflux as a test of plasma membrane leakage in Saccharomyces cerevisiae cells

Canadian Journal of Microbiology ◽

10.1139/cjm-2020-0040 ◽

2020 ◽

pp. 1-5

Author(s):

Ludmila Trilisenko ◽

Airat Valiakhmetov ◽

Tatiana Kulakovskaya

Keyword(s):

Saccharomyces Cerevisiae ◽

Plasma Membrane ◽

Propidium Iodide ◽

Membrane Integrity ◽

Yeast Cells ◽

Membrane Disruption ◽

Uptake System ◽

Plasma Membrane Integrity ◽

Medium Time ◽

The Difference

Plasma membrane integrity is a key to cell viability. Currently, the main approach to assessing plasma membrane integrity is the detection of penetration of special dyes, such as trypan blue and propidium iodide, into the cells. However, this method needs expensive equipment: a fluorescent microscope or a flow cytometer. Besides, staining with propidium iodide occasionally gives false-positive results. Here, we suggest the phosphate (Pi) leakage assay as an approach to assess the increase in permeability of the plasma membrane of yeast cells. We studied the dependence of phosphate efflux and uptake into Saccharomyces cerevisiae cells on the composition of the incubation medium, time, and ambient pH. The difference in optimal conditions for these processes suggests that Pi efflux is not conducted by the Pi uptake system. The Pi efflux in water correlated with the proportion of cells stained with propidium iodide. This indicated that Pi efflux is associated with cytoplasmic membrane disruption in a portion of the yeast cell population. The assay of Pi efflux was used to evaluate membrane disruption in S. cerevisiae cells treated with some heavy metal ions and detergents.

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A Comparison of Freezing Methods and Diluents Types on Post-Thaw Sperm Quality of Ram Sperm

Research in Agriculture Livestock and Fisheries ◽

10.3329/ralf.v7i2.48863 ◽

2020 ◽

Vol 7 (2) ◽

pp. 235-241

Author(s):

Pankaj Kumar Jha ◽

M Golam Shahi Alam ◽

Farida Yeasmin Bari

Keyword(s):

Plasma Membrane ◽

Sperm Quality ◽

Membrane Integrity ◽

Egg Yolk ◽

Sperm Parameters ◽

Plasma Membrane Integrity ◽

One Step ◽

Acrosome Integrity ◽

Ram Sperm

The effect of freezing methods and diluents types on post-thaw sperm quality of Bangladeshi ram semen was studied. Two freezing methods and three diluents was tested as pooling effects (freezing methods or diluents) on post-thaw sperm parameters; sperm motility (SM), viability (SV), plasma membrane integrity (SPMI) and acrosome integrity (SAI), respectively. From selected ten rams, eight ejaculates were used for each freezing group (freezing methods × diluents). Semen samples were diluted by using two-steps for hand-made tris-based diluents (20% egg yolk): D1 (7% glycerol) and D2 (5% glycerol), and one-step dilution for commercial diluents: D3 (Triladyl®) at 35°C. After 4h of equilibration of temperature at 5°C, diluted semen samples was aspirated into 0.25 mL straws, and sealed. Straws were frozen in liquid nitrogen (LN2) vapour using two methods: F1 (manually in Styrofoam box, using three-steps method; +5°C to -80°C at -11.33°C/min, -80°C to -120°C at -26.66°C/min, and -120°C to -140°C at - 13.33°C/min) and F2 (programmable bio-freezer, using two-steps method; +5°C to -100°C at - 20°C/min and -100°C to -140°C at -10°C/min). Two semen straws from each batch were evaluated (37°C for 20 sec) for sperm parameters. In pool effects between freezing methods; SAI differed significantly (P < 0.001). The SM (56%) and SV (72%) were observed competitive. However, SPMI (67.58 ± 2.02%) and SAI (76.13 ± 1.42%) were higher in F1. Among diluents, SM (P < 0.006), SV (P < 0.008), SPMI (P < 0.012) and SAI (P < 0.019) differed significantly. The SM (61.25 ± 1.80%), SV (77.13 ± 1.47%), SPMI (68.31 ± 1.91%) and SAI (74.75 ± 1.64%) were highest in D3. In conclusion, the combination of manual freezing (three-steps) and handmade tris-based diluents (20% egg yolk, 5% glycerol) is suitable and sustainable method for cryopreservation of ram semen. Res. Agric., Livest. Fish.7(2): 235-241, August 2020

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38 Ram sperm longevity after cryopreservation in extender containing L-carnitine

Reproduction Fertility and Development ◽

10.1071/rdv32n2ab38 ◽

2020 ◽

Vol 32 (2) ◽

pp. 145

Author(s):

C. Souza ◽

F. Brandão ◽

J. Santos ◽

V. Alfradique ◽

V. Brair ◽

...

Keyword(s):

Plasma Membrane ◽

Young Scientist ◽

Membrane Integrity ◽

Egg Yolk ◽

Intact Cells ◽

Plasma Membrane Integrity ◽

Head Displacement ◽

Thawing Process ◽

Semen Extender ◽

Ram Sperm

The cryopreservation process causes oxidative stress to the sperm cell, and the addition of antioxidants to the extender for semen freezing helps sperm protection. This study assessed the effect of L-carnitine (LC) concentrations (0, 5, or 10mM LC) on two ram semen extenders (Tris-egg yolk or the commercial optiXcell IMV medium (IMV Technologies)) for semen cryopreservation. Four Santa Inês rams were used during the breeding season. After semen collection, macroscopic and microscopic evaluations were performed, and a pool of semen was formed. The semen was diluted, and the final concentration was 100×106 per 0.25-mL straw. Cryopreservation was performed with a cooling rate of 0.25°C min−1 until 5°C, and the freezing rate used was 20°C min−1 from 5 to −120°C. After the freezing-thawing process and throughout incubation (38°C in 5% CO2) in Fert-Tyrode's albumin lactate pyruvate medium, every 1h for up to 3h, several parameters were evaluated: sperm kinetics, hypo-osmotic test, plasma membrane integrity, capacitation status, and lipid peroxidation level. We did not find any protective effect of LC on plasma membrane integrity, hypo-osmotic test, and capacitation status. The sperm kinetics values throughout incubation showed that Tris extender promoted better indices of staight-line velocity, linearity, wobble, and straightness than IMV extender along incubation, regardless of the presence of LC. There were no benefits of the LC addition throughout the incubation, and 10mM was deleterious to few parameters (amplitude of lateral head displacement, linearity, and wobble) compared with the control (0mM) in the Tris extender group. The plasma membrane integrity analysis revealed no differences (P>0.05) among the groups. The average number of intact cells (hypo-osmotic) was higher in Tris extender groups supplemented with 10mM LC at 1h and 5mM LC at 2h compared to the respective extender IMV groups. Regarding capacitation status, the Tris 5mM LC group had more acrosome-reacted cells when compared with the IMV 5mM LC group at 2h. At 3h, the percentage of acrosome-reacted cells was higher in the Tris 0-mM group when compared with the IMV 0-mM group. Regardless the presence of LC, IMV had higher (P<0.05) lipoperoxidation than the Tris treatments. In conclusion, LC supplementation in semen extender had no beneficial effect on freezing-thawing ram sperm and throughout incubation for up to 3h, with no difference in each time point evaluated. Under the conditions of this study, the use of Tris extender was superior to IMV extender for ram sperm. Financial support for this work came from the Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (Young Scientist Program of Our State; E-26/203.168/2017).

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Effect of different concentrations of trehalose and glycerol on the freezability of ram semen using soybean lecithin-based diluents

Animal Production Science ◽

10.1071/an13431 ◽

2015 ◽

Vol 55 (5) ◽

pp. 666 ◽

Cited By ~ 1

Author(s):

Zh. Bohlool ◽

M. Mohammadi ◽

M. Roostaei-Ali Mehr ◽

N. Ghavi Hossein-Zadeh

Keyword(s):

Plasma Membrane ◽

Sperm Motility ◽

Soybean Lecithin ◽

Membrane Integrity ◽

Sperm Viability ◽

Plasma Membrane Integrity ◽

Main Effect ◽

Acrosome Integrity ◽

Ram Sperm ◽

Desirable Effect

This study was conducted to determine the effect of different levels of trehalose and glycerol on ram sperm cryosurvival using lecithin-based diluents. Ejaculates were collected from four rams, pooled after initial evaluation, diluted with Tris-soybean lecithin extender and split into nine equal parts. A total of 0 (T0), 50 (T50) or 100 (T100) mM of trehalose and 3% (G3), 5% (G5) or 7% (G7) of glycerol were added to each part. Sperm motility, viability, plasma membrane integrity and acrosome integrity were evaluated immediately after thawing (0 h), and subsequently after 3 h and 6 h post-thawing incubation at 37°C. Results indicated that there was interaction between trehalose and glycerol on sperm motility. In addition, interaction of trehalose and glycerol with incubation time on sperm motility, viability, plasma membrane integrity and acrosome integrity was not significant (P > 0.05). Sperm motility was greatest in the sperm treated with 100 mM trehalose and 7% glycerol (27%; P < 0.05). The effect of trehalose was significant on viability and plasma membrane integrity of ram spermatozoa (P < 0.05). The main effect of trehalose showed that sperm viability was higher in T100 (47.06%) than T50 (53.96%; P < 0.05). The highest membrane integrity was observed in T100 (47.04%; P < 0.05). Membrane integrity was higher (P < 0.05) in G5 (49.97%) than G3 (41.56%) and there was no difference between G7 (46.86%) and G3 (41.56%; P > 0.05). The best sperm viability and plasma membrane integrity was observed at 0 h (65.75% and 51.58%, respectively). It was concluded that simultaneous use of 7% glycerol and 100 mM trehalose had a desirable effect on motility of ram frozen–thawed sperm.

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Comparision of DNA fragmentantion and plasma membrane integrity between chilled and frozen semen of bulls

Reproduction Abstracts ◽

10.1530/repabs.1.p248 ◽

2014 ◽

Author(s):

Mello Papa Patricia de ◽

Carlos Ramires Neto ◽

Priscilla Nascimento Guasti ◽

Rosiara Rosaria Dias Maziero ◽

Yame F R Sancler-Silva ◽

...

Keyword(s):

Plasma Membrane ◽

Membrane Integrity ◽

Plasma Membrane Integrity ◽

Frozen Semen

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Plasma membrane integrity in health and disease: significance and therapeutic potential

Cell Discovery ◽

10.1038/s41421-020-00233-2 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Catarina Dias ◽

Jesper Nylandsted

Keyword(s):

Plasma Membrane ◽

Therapeutic Potential ◽

Calcium Influx ◽

Membrane Integrity ◽

Cell Types ◽

Physical Parameters ◽

Membrane Repair ◽

Plasma Membrane Integrity ◽

Repair Mechanisms ◽

And Function

AbstractMaintenance of plasma membrane integrity is essential for normal cell viability and function. Thus, robust membrane repair mechanisms have evolved to counteract the eminent threat of a torn plasma membrane. Different repair mechanisms and the bio-physical parameters required for efficient repair are now emerging from different research groups. However, less is known about when these mechanisms come into play. This review focuses on the existence of membrane disruptions and repair mechanisms in both physiological and pathological conditions, and across multiple cell types, albeit to different degrees. Fundamentally, irrespective of the source of membrane disruption, aberrant calcium influx is the common stimulus that activates the membrane repair response. Inadequate repair responses can tip the balance between physiology and pathology, highlighting the significance of plasma membrane integrity. For example, an over-activated repair response can promote cancer invasion, while the inability to efficiently repair membrane can drive neurodegeneration and muscular dystrophies. The interdisciplinary view explored here emphasises the widespread potential of targeting plasma membrane repair mechanisms for therapeutic purposes.

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