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1

Structural damage to nuclear DNA in mammalian spermatozoa: its evaluation techniques and relationship with male infertility

100%
Fraser L.
Polish Journal of Veterinary Sciences
|
2004
|
tom 07
|
nr 4
Diagnosis of the fertilizing ability of a semen sample is important for consistently high reproductive efficiency. Disturbances in the organization of the genomic material in sperm nuclei can have a serious impact on the growth of the offspring, therefore a stable nuclear matrix is crucial for participation in embryonic development. Routine semen analysis investigates parameters such as sperm motility and morphology, but does not examine the nuclear DNA integrity of spermatozoa. It has been suggested that altered nuclear chromatin structure or damaged DNA in spermatozoa is implicated as a possible cause of increased infertility in males. Therefore, it is crucial to develop and use accurate and diagnostic tests, which may provide better prognostic capabilities than the standard sperm assessments. This article reviews and discusses some of the current techniques employed for evaluating chromatin structure or DNA damage in spermatozoa. These different techniques include the comet assay, sperm chromatin structure assay (SCSA), acridine orange test (AOT), tritium-labelled 3H-actinomycin D (3H-AMD) incorporation assay, terminal TdT-mediated dUTP-nick-end labelling (TUNEL) assay, in-situ nick translation (ISNT) assay, DNA breakage detection-fluorescence in-situ hybridizations (DBD-FISH) assay and sperm chromatin dispersion (SCD) test. The aforementioned assays, which are considered independent measure of sperm quality, may help to detect subtle defects in the chromatin structure or DNA integrity, and thereby assist in semen quality assessment. The relationship between DNA damage and male infertility is also addressed.
2

Characteristics of spermatozoa of whole ejaculate and sperm-rich fraction of dog semen following exposure to media varying in osmolality

63%
Strzezek R., Fraser L.
Reproductive Biology
|
2009
|
tom 09
|
nr 2
3

The use of comet assay to assess DNA integrity of boar spermatozoa following liquid preservation at 5 degrees Celsius and 16 degrees Celsius

63%
Fraser L., Strzezek J.
Folia Histochemica et Cytobiologica
|
2004
|
tom 42
|
nr 1
4
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Supplementation of different concentrations of Orvus Es Paste (OEP) to ostrich egg yolk lipoprotein extender improves post-thaw boar semen quality

51%
Fraser L., Jasiewicz E., Kordan W.
Polish Journal of Veterinary Sciences
|
2014
|
tom 17
|
nr 2
This study aimed to compare post-thaw quality of boar semen following freezing in an ostrich egg yolk lipoprotein (LPFo) extender supplemented with 0%, 0.25% and 0.50% Orvus Es Paste (OEP). Sperm assessments included total motility (TMOT), mitochondrial function (MF), plasma membrane integrity (PMI) and acrosome integrity (normal apical ridge, NAR). Considerable variations among boars and OEP treatments had a significant effect (P < 0.001) on post-thaw sperm characteristics. It was observed that post-thaw sperm characteristics were significantly compromised in semen samples frozen in the absence of OEP. By contrast, lactose-LPFo-glycerol extender supplemented with either 0.25% OEP or 0.50% OEP markedly enhanced post-thaw sperm characteristics. In all boars, there were no marked differences in post-thaw sperm TMOT between the freezing extenders supplemented with 0.25% and 0.50% OEP. However, a decline in the percentage of post-thaw motile spermatozoa was more pronounced in the extender supplemented with 0.50% OEP following a 120-min incubation period. Furthermore, the proportions of frozen-thawed spermatozoa with MF, PMI and NAR acrosomes varied significantly among the boars in the OEP-supplemented extenders. The findings of this study indicate that different OEP concentrations, in the presence of ostrich egg yolk lipoproteins, could have varying effects on post-thaw sperm survival.
5
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Total RNA quality in boar spermatozoa with different freezability

51%
Fraser L., Brym P., Mogielnicka-Brzozowska M., Wasilewska K.
Polish Journal of Veterinary Sciences
|
2019
|
tom 22
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nr 1
6

Interactions of egg yolk lipoprotein fraction with boar spermatozoa assessed with a fluorescent membrane probe

51%
Fraser L., Zasiadczyk L., Strzezek J.
Folia Histochemica et Cytobiologica
|
2010
|
tom 48
|
nr 2
292-298
7

Differentially expressed gene transcripts in boar spermatozoa analyzed by RNA-Seq

51%
Fraser L., Brym P., Wasilewska K.
Acta Biochimica Polonica
|
2018
|
tom 65
|
nr S2
8

Fluorometric assessments of viability and mitochondrial status of boar spermatozoa following liquid storage

51%
Fraser L., Lecewicz M., Strzezak J.
Polish Journal of Veterinary Sciences
|
2002
|
tom 05
|
nr 2
9
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Isolation and characterization of zinc-binding proteins of canine seminal plasma

51%
Mogielnicka-Brzozowska M., Fraser L., Czarzasta J., Kordan W.
Polish Journal of Veterinary Sciences
|
2012
|
tom 15
|
nr 3
Zinc-binding proteins from seminal plasma (ZnBPs) originate in the secretions of different accessory sex glands and are implicated in key events associated with sperm-egg fertilization processes. This study describes the isolation and characterization of the ZnBPs of canine seminal plasma. Ejaculates were collected from three crossbred dogs for a 2-week period. The ZnBPs as well as non zinc-binding proteins (nZnBPs) were isolated by zinc-dependent affinity chromatography. The isolated fractions were subjected to native gel electrophoresis (one-dimensional polyacryamide gel electrophoresis, PAGE) and sodium dodecyl sulphate polyacryamide gel electrophoresis (SDS-PAGE), using denaturing and reducing conditions. Zinc-elution profile using affinity chromatography displayed two protein fractions represented by the nZnBPs and ZnBPs, respectively. Using native gel electrophoresis, it was found that both the nZnBPs and ZnBPs occurred in their native state as aggregates, ranging from 140 to 669 kDa. The nZnBPs were disaggregated into 8 protein bands, with molecular weights ranging from 10.7 to 79.7 kDa, following SDS-PAGE analysis. By contrast, SDS-PAGE analysis of the ZnBPs revealed 13 protein bands, with molecular weights ranging from 11.6 to 152.3 kDa. Densitometric analysis showed that 46-48% of nZnBPs could be accounted by protein fractions with molecular weights of 10.7 and 14.2 kDa. Also, 2 protein fractions with molecular weights of 11.6 and 14.3 kDa, were predominant in ZnBPs, accounting for approximately 28-30% of the total proteins. These results demonstrate the zinc-binding capacity of proteins secreted by the canine prostate. The findings of this study indicate that ZnBPs of canine seminal plasma comprise several protein fractions, which might be implicated in the reproductive processes in the dog.
10

Comparative study of different methods for plasma membrane integrity assessment of frozen-thawed boar spermatoza

51%
Fraser L., Zasiadczyk L., Lecewicz M., Kordan W.
Bulletin of the Veterinary Institute in Puławy
|
2011
|
tom 55
|
nr 2
In this study, different assays were used to assess the structural and functional integrity of the sperm plasma membrane following freezing-thawing of the whole ejaculates (WEs) and sperm-rich fractions (SRFs) of boar semen. Besides sperm viability assessments (motility and mitochondrial membrane potential using a mitochondrial specific dye, JC-1 with propidium iodide, PI), sperm plasma membrane integrity (PMI) assessments were determined simultaneously using different membrane-based tests (SYBR- 14/PI and carboxyfluorescein diacetate (CFDA) with PI (CFDA/PI), and the hypo-osmotic swelling (HOS) test). ANOVA results showed that boar variability had a significant effect on the analysed parameters of post-thaw sperm characteristics. Spermatozoa harvested from the WEs exhibited a marked decline in post-thaw viability, manifested in reduced motility and mitochondrial membrane potential, than those originated from the SRFs after freezing-thawing. Cryopreservation compromised sperm PMI, as indicated in a significant decline in SYBR-stained, CFDA-stained or HOS-positive sperm cells, irrespective of the ejaculate collection procedure. It was observed that the membrane-based tests were strongly inter-correlated. Furthermore, agreement between the measurements of the membrane-based tests was confirmed by the Bland-Altman scatter plots of differences, suggesting that these tests could detect the same sperm cohorts, which were susceptible to cryo-induced membrane damage. The findings of this study indicate that dual fluorescent staining with SYBR-14/PI and CFDA/PI assays, in combination with the HOS test, provide more precise description of the sperm populations in frozen-thawed boar semen.
11

Seasonal changes in antioxidant defence systems in seminal plasma and fluids of the boar reproductive tract

51%
Koziorowska-Gilun M., Koziorowski M., Strzezek J., Fraser L.
Reproductive Biology
|
2011
|
tom 11
|
nr 1
12

Effect of different storage temperatures on the metabolic activity of spermatozoa following liquid storage of boar semen

51%
Dziekonska A., Fraser L., Strzezek J.
Journal of Animal and Feed Sciences
|
2009
|
tom 18
|
nr 4
13

The antigenic character of zinc-binding proteins and their localization in boar reproductive tract - A preliminary study

51%
Mogielnicka-Brzozowska M., Fraser L., Strzezek J., Kordan W.
Acta Biochimica Polonica
|
2013
|
tom 60
|
nr 2
 In this study immunoelectrophoretic and double immunodiffusion analyses were used to investigate the antigenic character of zinc-binding proteins (ZnBPs), whereas the indirect immunofluorescence technique was used to identify their origin in boar reproductive tract. The mmunoelectrophoretic analysis of ZnBPs of the seminal plasma resulted in the appearance of three antigenic protein complexes, while specific immunoreactivity patterns of the anti-ZnBP serum were detected by double immunodiffusion analysis. Indirect immunofluorescence technique confirmed that ZnBPs were secreted by different reproductive tract tissues, suggesting their contributions to the seminal plasma.
14

Effect of extender composition and storage temperatures on motility of preserved boar semen

51%
Fraser L., Lecewicz M., Krasicki R., Strzezek J.
Journal of Animal and Feed Sciences
|
2002
|
tom 11
|
nr 4
15

Identification of amplified fragment length polymorphism markers associated with freezability of boar semen - a preliminary study

51%
Fraser L., Pareek C. S., Strzezek J.
Medycyna Weterynaryjna
|
2008
|
tom 64
|
nr 05
In this study the amplified fragment length polymorphism (AFLP) technique, based on the analysis of genomic restriction fragments by polymerase chain reaction (PCR) amplifications, was utilized to identify genomic markers associated with differences in the freezability of boar semen. Collected from seven Polish Large White boars, semen was cooled in a lactose-lipoprotein fractions-glycerol extender (lac-LPFo-G), packaged into aluminum tubes and frozen using a programmable computer freezer. The DNA, isolated from each boar, was screened for AFLP markers using different primer pair combinations for selective amplifications. Sperm samples prior to and after freezing-thawing were analyzed for motility, mitochondrial function (Rhodamine 123), plasma membrane integrity (SYBR-14 positive) and DNA integrity using the single cell gel electrophoresis (neutral Comet assay). The authors’ preliminary findings have indicated that there were consistent inter-boar variations in terms of post-thaw sperm characteristics. Distinct differences in AFLP DNA patterns in each boar were detected using different primer combinations. Furthermore, amplified DNA fragments, with similar base pairs, were detected only in the DNA profile of boars with good semen freezability. The AFLP technique can be used to select reproductive boars that produce semen with good quality characteristics for freezing-thawing procedure.
16

Fertilizing capacity of boar semen frozen in an extender supplemented with ostrich egg yolk lipoprotein fractions - A pilot study

51%
Fraser L., Strzezek R., Strzezek J.
Polish Journal of Veterinary Sciences
|
2007
|
tom 10
|
nr 3
A limited field trial was performed to evaluate the fertilizing capacity of boar spermatozoa frozen in an extender supplemented with lipoprotein fractions isolated from ostrich egg yolk (LPFo). Boar semen, diluted in an extender containing lactose with lyophilized lipoprotein fractions, glycerol and Orvus Es Paste (lactose-LPFo-G), was frozen using a controlled programmable freezer. Sperm characteristics, such as motility, plasma membrane and acrosome integrity, and mitochondrial function were monitored. Post-cervical artificial inseminations (post-CAIs) in multiparous sows (Polish Large White) were performed using the Soft & Quick® catheter/cannula set. Sows were inseminated 2 to 3 times within one oestrus. Possible returns of sows to oestrus were determined from 21 to 30 days after post-CAIs. In this field trial, sows inseminated with 2 x 109 motile frozen-thawed spermatozoa resulted in pregnancy and farrowing rates of 75%, respectively. The average piglets born live was 10.5 ± 0.4 (mean ± SEM). The data of this study showed that post-CAI of boar semen frozen in LPFo-containing extender has the potential to provide acceptable fertility results. Further investigations are needed to elucidate the cause of variations in pregnancy/farrowing rate associated with frozen-thawed boar semen.
17

Age-dependent and seasonal changes in the activity of platelet-activating factor acetylhydrolase [PAF-AH] of boar seminal plasma in relation to the content of calcium ions

51%
Kordan W., Strzezek J., Fraser L., Soliwoda D.
Animal Science Papers and Reports
|
2003
|
tom 21
|
nr 1
The objective of this study was to determine the activity of platelet-activating factor acetylhydrolase (PAF-AH) and the content of calcium ions (Ca2+) of boar seminal plasma in relation to season and animal age. Wide fluctuations in PAF-AH activity and Ca2+ content of plasma were observed. PAF-AH activity ranged from 334.2 to 524.3 nmol PAF hydrolyzed/min/mg protein, whereas the Ca2+ content from 2.4 to 3.4 mg/100 ml. In some cases PAF-AH activity was positively correlated with Ca2+ content.Both the PAF-AH activity and Ca2+ content of plasma depended on the season and age of the boars.The age-related and seasonal changes observed in PAF-AH activity suggest that the enzyme may play a role in boar reproductive functions.
18

Functions of platelet activating factor [PAF] in mammalian reproductive processes: a review

51%
Kordan W., Strzezek J., Fraser L.
Polish Journal of Veterinary Sciences
|
2003
|
tom 06
|
nr 1
Platelet activating factor, PAF, (l-0-alkyl-2-acetyl-sn-glycero3-phosphorylcholine) is a naturally occurring compound of membrane phospholipid. The aim of this article was to briefly review current research on the significant role of PAF in mammalian reproductive functions. The involvement of this phospholipid in the female reproductive processes may indicate that it plays an important role in ovarian follicular development, reproductive cycle and pregnancy. A full understanding of PAF functions in sperm motility, capacitation and the acrosome reaction is mandatory to correctly interpret its role in the male reproductive processes. This review also addressed the importance of the mechanism regulating PAF metabolism, PAF-acetylhydrolase (PAF-AH), during the membrane fusion events associated with fertilization.
19

Domaciczna inseminacja loch

51%
Lecewicz M., Fraser L., Strzezek J.
Hodowca Trzody Chlewnej
|
2004
|
nr 2
18-19
20

Metabolic activity of boar semen stored in different extenders supplemented with ostrich egg yolk lipoproteins

45%
Dziekonska A., Kinder M., Fraser L., Strzezek J., Kordan W.
Journal of Veterinary Research
|
2017
|
tom 61
|
nr 1
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