Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 103
Filtrar
Mais filtros

País/Região como assunto
Intervalo de ano de publicação
1.
Reprod Domest Anim ; 59(8): e14679, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39086072

RESUMO

In vitro capacitation allows for a greater understanding of the mechanisms underlying fertilization and the development of improved reproductive techniques for improving fertility rates in porcine. Tyrodes albumin lactate pyruvate (TALP) and modified Krebs Ringers Broth (m-KRB) are two medias that are commonly used in research experiments to induce capacitation in boar spermatozoa (Cañón-Beltrán et al., Theriogenology, 198, 2023 and 231; Oberlender et al., Archivos de Medicina Veterinaria, 44, 2012 and 201; Sahoo et al., International Journal of Biological Macromolecules, 241, 2023 and 124502). Moreover, understanding the morphological and functional changes in boar spermatozoa at different hours of capacitation periods might aid in the development of novel techniques for improving sperm quality and increasing the litter size. This study was carried out to investigate the effect of Tyrode albumin lactate pyruvate and modified Krebs Ringers Broth media on in vitro capacitation of HD-K75 boar spermatozoa at three different periods of incubation. A total of 24 ejaculate from four clinically healthy, 10-12 months aged HD-K75 boars, maintained at ICAR-All India Coordinated Research Project (AICRP) on pig were selected. Semen was collected by 'Simple fist' method using a portable dummy. The semen samples having 200 mL volume, 103 × 106 spermatozoa/ml concentration and 70% initial motility were selected and split into two parts and suspended in TALP and m-KRB media, respectively, and incubated for 5 h at 37°C. Seminal parameters viz. sperm viability, plasma membrane integrity and acrosomal integrity were estimated in the samples at 0, 3 and 5 h of incubation. This study revealed that there was significant variation between media in live acrosome-reacted (p < .05) and HOST-reacted (p < .01) spermatozoa, while between capacitation periods significant (p < .01) variation was observed in hyperactivated spermatozoa, live acrosome-reacted spermatozoa, HOST-reacted spermatozoa, FITC-labelled PSA, extracellular protein and sperm cholesterol. Non-significant variation was observed in total phospholipid. TALP showed overall better consequence on sperm viability, plasma membrane and acrosomal integrity of boar spermatozoa. From this study, it could be concluded that both TALP and m-KRB media were virtuous to induce capacitation in HD-K75 boar spermatozoa. TALP media, however, had a better effect on sperm viability, plasma membrane and acrosomal integrity of boar spermatozoa. Out of the three different periods, 3 h capacitation period resulted in significantly (p < .01) higher incidence of sperm viability, plasma membrane and acrosomal integrity in HD-K75 boar spermatozoa.


Assuntos
Capacitação Espermática , Espermatozoides , Animais , Masculino , Capacitação Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Suínos , Meios de Cultura/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Análise do Sêmen/veterinária
2.
Reprod Domest Anim ; 58(2): 238-245, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36250516

RESUMO

In the current article, a developed, patented method denoted the 'Camel Semen Collection Kit-CSCK', was designed to solve the problem of semen collection in dromedary camels. CSCK is composed of three main parts: (1) Semen collection sac: made from supersensitive flexible low-density polyethylene- (LDPE); (2) Metal stainless steel applicator: designed to introduce the collection sac intravaginally and fixate it to the vaginal wall of a female camel through air insufflation; (3) Fixation sticker: a cushion sheet sticker is used to secure the outer portion of the collection sac to the female's perineal area. Semen was collected twice a week from eight dromedary bulls by using electroejaculation (EJ), artificial vagina (AV) and CSCK. Successful semen collections were 81.3%, 84.4% and 43.8% using EJ, CSCK and AV techniques respectively. Semen obtained by EJ technique showed lower semen volume, gross activity, sperm concentration, total sperm motility and percentage of live sperm cells compared to the other two techniques. Semen collected by CSCK showed a longer collection period and higher volume, gross activity, sperm motility and percentage of live spermatozoa and a lower rate of visible contamination compared to AV technique. The advantages and disadvantages of the three techniques were compared and discussed. In conclusion, CSCK represents a practical and easy method to reliably collect high-quality semen from any untrained male dromedary camel and may facilitate the widespread application of assisted reproductive technologies (ARTs) on a large scale in this species.


Assuntos
Camelus , Análise do Sêmen , Sêmen , Manejo de Espécimes , Animais , Feminino , Masculino , Análise do Sêmen/veterinária , Análise do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides/citologia , Manejo de Espécimes/métodos , Manejo de Espécimes/veterinária
3.
Int J Mol Sci ; 24(15)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37569900

RESUMO

The spermatozoa have limited antioxidant defences, a high polyunsaturated fatty acids content and the impossibility of synthesizing proteins, thus being susceptible to oxidative stress. High levels of reactive oxygen species (ROS) harm human spermatozoa, promoting oxidative damage to sperm lipids, proteins and DNA, leading to infertility. Coenzyme A (CoA) is a key metabolic integrator in all living cells. Recently, CoA was shown to function as a major cellular antioxidant mediated by a covalent modification of surface-exposed cysteines by CoA (protein CoAlation) under oxidative or metabolic stresses. Here, the profile of protein CoAlation was examined in sperm capacitation and in human spermatozoa treated with different oxidizing agents (hydrogen peroxide, (H2O2), diamide and tert-butyl hydroperoxide (t-BHP). Sperm viability and motility were also investigated. We found that H2O2 and diamide produced the highest levels of protein CoAlation and the greatest reduction of sperm motility without impairing viability. Protein CoAlation levels are regulated by 2-Cys peroxiredoxins (PRDXs). Capacitated spermatozoa showed lower levels of protein CoAlation than non-capacitation cells. This study is the first to demonstrate that PRDXs regulate protein CoAlation, which is part of the antioxidant response of human spermatozoa and participates in the redox regulation associated with sperm capacitation.


Assuntos
Antioxidantes , Peróxido de Hidrogênio , Humanos , Masculino , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Diamida/metabolismo , Motilidade dos Espermatozoides , Sêmen/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Espermatozoides/metabolismo , Peroxirredoxinas/metabolismo
4.
Ecotoxicol Environ Saf ; 244: 114038, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36075120

RESUMO

Cypermethrin contamination was a potential threat to soil organisms. In the present work, reproductive damage in earthworms (Amynthas corticis) exposed to cypermethrin was investigated. It was found that earthworms could absorb and accumulate residual cypermethrin in soil, and also earthworm activities helped accelerate the degradation of cypermethrin in soil. The accumulation of cypermethrin in earthworms induced sperm damage, and cypermethrin not only caused the imbalance of calcium homeostasis in earthworm sperm cells by inhibiting earthworm sperm Ca2+-ATP and Ca2+-Mg2+-ATP enzyme activities but also caused barriers in acrosome reaction. It also affected sperm energy supply of earthworms by inhibiting the activity of Na+-K+-ATPase and Mg2+-ATPase of earthworm sperm. Meanwhile, the inhibition of acrosome enzyme activity of earthworm sperm by cypermethrin led to hinder fertilization and reduced cocoon production of earthworms, and the damage of cypermethrin to sperm of earthworm was a significant cause of its reproductive toxicity. The results of the evaluation of IBR index showed that reproductive toxicity of cypermethrin to earthworms reduced with the increasing time. The decreased reproductive toxicity of cypermethrin to earthworms at the later stage of exposure (42-56 d) might be due to a combination of reduced absorption of cypermethrin in soil by earthworms, decreased accumulation of cypermethrin in the body, and improved sperm capacitation.


Assuntos
Oligoquetos , Poluentes do Solo , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/metabolismo , Masculino , Oligoquetos/metabolismo , Piretrinas , Sêmen/química , Solo , Poluentes do Solo/análise
5.
Andrologia ; 54(5): e14381, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35112373

RESUMO

Up to 20% of male infertility is caused by abnormal DNA organization of the sperm and anomalies of the sperm apoptosis. The aim of this study was to investigate the sperm DNA apoptosis and viability in patients undergoing intrauterine insemination (IUI) and intracytoplasmic sperm injection (ICSI). In the second part of the analysis, sperm DNA apoptosis and viability were investigated in patients with oligozoospermia and normospermia respectively. A total of 45 IUI and 38 ICSI patients were included in this study. Annexin V analysis was performed to investigate the sperm viability, and TUNEL assay was used to evaluate the sperm DNA apoptosis. Further investigations using 12 oligozoospermia and 11 control samples for sperm viability and sperm DNA apoptosis at different incubation periods and temperatures were performed. The results of this study showed a negative correlation between the sperm DNA apoptosis in IUI patients, but no relationship was observed for the ICSI patients. The second part of this study showed that incubation of semen samples at 37°C for 3 h has detrimental effects on the sperm DNA integrity. In conclusion, the incubation of semen at high temperatures affects the sperm quality. The results of this study showed that these tests can be beneficial for the infertile couples to achieve pregnancy.


Assuntos
Oligospermia , Injeções de Esperma Intracitoplásmicas , Apoptose , DNA , Feminino , Humanos , Inseminação , Masculino , Gravidez , Taxa de Gravidez , Espermatozoides
6.
Andrologia ; 54(2): e14323, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34845741

RESUMO

An in vitro spermicidal effect of aqua-methanolic (2:3) extract of Thevetia peruviana leaves on human spermatozoa was evaluated in a dose-dependent manner (20, 40, 80 and 160 mg/ml) at a 1:1 ratio. Sperm motility, viability, hypo-osmotic swelling (HOS) and acrosomal status and function tests were performed immediately (20 s), and after 5 and 10 min of exposure of the spermatozoa to the extract of Thevetia peruviana leaves at different dose concentrations. Nuclear chromatin decondensation (NCD) test, DNA fragmentation test and sperm revival test were also evaluated. The sperm motility was affected immediately at a dose of 20 mg/ml and reduced gradually at doses of 40 and 80 mg/ml of Thevetia peruviana extract. Complete immobilisation of spermatozoa was observed at 160 mg /ml dose of this extract treatment within 5 min. 50% immobilisation of spermatozoa (EC50) was observed at 28 mg/ml dose of Thevetia peruviana extract within 20 s. The sperm viability decreased significantly at a higher concentration of extract, and all spermatozoa were found to be non-viable after 10 min when treated with 160 mg/ml dose of Thevetia peruviana extract. HOS and NCD of spermatozoa also reduced gradually at a higher concentration of extract administration. The percentage of DNA damage in spermatozoa was four times greater than in the control group. The findings indicate that the hydro-methanolic extract of Thevetia peruviana leaves possesses appreciably potent spermicidal activity through an in vitro model, which may explore an effective vaginal contraceptive.


Assuntos
Espermicidas , Thevetia , Humanos , Extratos Vegetais/farmacologia , Folhas de Planta , Motilidade dos Espermatozoides , Espermicidas/farmacologia , Espermatozoides
7.
Reprod Domest Anim ; 57(2): 228-232, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33908090

RESUMO

We report the development of a hydrogel-based approach to select bull spermatozoa, a crucial step for successful assisted reproductive techniques (ARTs). Hyaluronic acid (HA) semi-interpenetrated N-isopropylacrylamide (PNIPAM) co-20% N-Tris (hydroxymethyl) methyl acrylamide (HMA) hydrogels were synthetized on glass surfaces and cultured in presence of frozen-thawed bull spermatozoa. A fraction of motile bull spermatozoa population strongly attached to hydrogels and was partially released by treatment with hyaluronidase. Fifty-nine (59 ± 7.24) per cent of sperm cells attached to PNIPAM-HMA-HA hydrogels and 31.16 ± 4.81% of them were released upon treatment with medium containing hyaluronidase. This attached-released sperm fraction has acceptable characteristics of progressive motility (50.0 ± 5.0%), vigour (4), high viability (58.7 ± 11.7%) and low percentage of acrosome reacted spermatozoa (23.36 ± 4.1%). Our findings indicate that PNIPAM-HMA-HA hydrogels are non-toxic and allow the selection of high-quality sperm cells for ART.


Assuntos
Preservação do Sêmen , Motilidade dos Espermatozoides , Acrossomo , Animais , Bovinos , Criopreservação/veterinária , Ácido Hialurônico , Hidrogéis , Masculino , Preservação do Sêmen/veterinária , Espermatozoides
8.
Biol Reprod ; 104(5): 1154-1161, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33590844

RESUMO

Sperm quality is an important indicator of male fertility, and a suitable biomarker enables the selection of high-quality spermatozoa. We previously found that L-amino acid oxidase encoded by the L-amino acid oxidase 1 (Lao1) gene exerts biological roles in the mammary gland and brain by converting specific L-amino acids into keto acids, ammonia, and hydrogen peroxide (H2O2). Here, we describe the role of Lao1 in male reproduction. Lao1-deficient (Lao1-/-) male mice generated fewer pregnant embryos and pups as well as lower ratios of fertilized oocytes and even ovulated number was not different, suggesting that male subfertility caused the smaller litters. We found that LAO1 expressed in acrosomes is associated with high malformation ratios and low viability of Lao1-/- sperm. Wild-type (WT) sperm produced more H2O2 than Lao1-/- sperm, and 10 µM H2O2 restored knockout (KO) sperm viability in vitro. In addition, the sperm ratio of induced acrosome reaction was higher in WT than in Lao1-/- sperm incubated with the calcium ionophore A23187. Moreover, LAO1 expression was abundant in bovine sperm with high fertilization ratios. We concluded that LAO1 localized in the sperm acrosome influences sperm viability and morphology as well as the acrosome reaction, and that LAO1-deficient sperm might cause male subfertility. Thus, LAO1 might serve as a novel marker for selecting high-quality spermatozoa, especially for livestock reproduction.


Assuntos
L-Aminoácido Oxidase/genética , Reprodução/genética , Espermatozoides/enzimologia , Animais , Bovinos , L-Aminoácido Oxidase/metabolismo , Masculino , Camundongos
9.
Cryobiology ; 98: 239-244, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33223006

RESUMO

The biological consequences of semen samples preconditioning with photobiomodulation (PBM) were studied on human sperm cells post cryopreservation. Donated semen samples were collected from 22 married men with normal sperm parameters according to World Health Organization (WHO) criteria. Included samples were divided into control and PBM-preconditioning (one session, 810 nm, diode laser, and 0.6 J/cm2) groups before cryopreservation procedure. Progressive sperm motility (PSM), morphology, viability, sperm mitochondrial membrane potential(MMP), intracellular reactive oxygen species (ROS) and lipid peroxidation of sperm cells were assessed post thawing. PBM preconditioning of cryopreserved semen samples most prominently increased the PSM percentage 30 min post thawing (p = 0.000).Application of PBM before cryopreservation significantly increased the number of viable spermatozoa (p = 0.000), increased significantly the number of spermatozoa with high MMP (p = 0.004) and decreased significantly the number of spermatozoa with low MMP post-thawing(P = 0. 007)compared to control group. Cryopreserved human sperm cells with PBM preconditioning showed significant decrease in the levels of intracellular ROS (47.66 ± 2.14 versus 60.42 ± 3.16, p = 0.002) and lipid peroxidation (3.06 ± 0.13 versus 3.68 ± 0.27, p = 0.05)compared to control group. Our findings, as the first evidence, indicated that PBM-preconditioning of human semen before cryopreservation provides a real and substantial advantage. This might lead to a novel strategy in improving PBM application in the procedures of assisted reproductive technologies.


Assuntos
Criopreservação , Preservação do Sêmen , Criopreservação/métodos , Humanos , Masculino , Sêmen , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
10.
Adv Gerontol ; 34(1): 96-101, 2021.
Artigo em Russo | MEDLINE | ID: mdl-33993668

RESUMO

The work is devoted to the analysis of age-related changes in human spermatozoa and their functional properties in men aged 26-47 years. The work used ejaculate obtained from 54 men as part of the in vitro fertilization procedure. The patients were divided into three groups (26-29, 30-34 and over 35 years old). In the course of the work, the parameters of the spermogram were collected, as well as the results of assessing the viability of spermatozoa, obtained using the method of flow cytometry, and also a retrospective analysis of the effectiveness of in vitro fertilization was carried out. It was found that the average values of spermogram parameters in groups were within the physiological norm, however, about 59% of patients had individual deviations in terms of 1-3 indicators. Cytometric analysis revealed a rapid increase with age in functional disorders of spermatozoa, affecting the recognition and penetration apparatus (acrosome), the energy apparatus of the cell (its mitochondrion) and the density of chromatin in its nucleus. The result is a decrease in the probability of fertilization from 88% at 26-29 years old to 61% after 35 years, even with in vitro fertilization. The significance of the results obtained for the analysis of age-related changes in the male reproductive system and the practice of treating male infertility is substantiated.


Assuntos
Fertilização , Infertilidade Masculina , Acrossomo , Humanos , Masculino , Estudos Retrospectivos , Espermatozoides
11.
Trop Anim Health Prod ; 53(1): 182, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33634325

RESUMO

This study investigated whether dilution rate and successive semen collections influenced sperm viability, morphology, motility and male sexual motivation in sexually mature South African Merino rams (SAMR). Semen was collected from 11 rams up to either sperm or behavioural exhaustion. Semen was then immediately serial diluted to make 0, 2, 4, 8 and 16× dilutions with Hams F10 diluent. Following dilution, sperm motility was evaluated using computer-assisted sperm analysis (SCA®), while sperm morphology and viability were assessed using nigrosin-eosin staining and SYBR14/PI, respectively. Male sexual motivation was recorded by reaction time to first mount, while male dexterity was calculated as the ratio of mounts to ejaculations. An increase of dilution rate did not affect sperm motility (P > 0.05) but resulted in a significant decrease in the percentage of live normal sperm (P < 0.05). Furthermore, while sperm concentration and number decreased with semen collection number (P < 0.05), no effect was detected on sperm viability, morphology and motility (P > 0.05), except for average curvilinear velocity which showed a biphasic trend (P < 0.05). Mating success and reaction time were negatively affected by successive semen collections (P < 0.05), while male dexterity was unaffected (P > 0.05). Nevertheless, relatively high numbers of motile sperm (>2 billion) were collected up to the 4th successive semen collection, with a short initial reaction period (<25 s) and good success rate (>65%). SAMR thus withstood frequent semen collections without affecting their sperm reserves or sexual motivation. Further studies are required to investigate optimal conditions for semen collection and artificial insemination in this breed.


Assuntos
Preservação do Sêmen , Motilidade dos Espermatozoides , Animais , Masculino , Motivação , Sêmen , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Ovinos , Contagem de Espermatozoides/veterinária , Espermatozoides
12.
BMC Genomics ; 21(1): 571, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32819278

RESUMO

BACKGROUND: Queen failure is a persistent problem in beekeeping operations, but in the absence of overt symptoms it is often difficult, if not impossible, to ascertain the root cause. Stressors like heat-shock, cold-shock, and sublethal pesticide exposure can reduce stored sperm viability and lead to cryptic queen failure. Previously, we suggested candidate protein markers indicating heat-shock in queens. Here, we further investigate these heat-shock markers and test new stressors to identify additional candidate protein markers. RESULTS: We found that heat-shocking queens for upwards of 1 h at 40 °C was necessary to induce significant changes in the two strongest candidate heat-shock markers, and that relative humidity significantly influenced the degree of activation. In blind heat-shock experiments, we tested the efficiency of these markers at assigning queens to their respective treatment groups and found that one marker was sufficient to correctly assign queens 75% of the time. Finally, we compared cold-shocked queens at 4 °C and pesticide-exposed queens to controls to identify candidate markers for these additional stressors, and compared relative abundances of all markers to queens designated as 'healthy' and 'failing' by beekeepers. Queens that failed in the field had higher expression of both heat-shock and pesticide protein markers, but not cold-shock markers. CONCLUSIONS: This work offers some of the first steps towards developing molecular diagnostic tools to aid in determining cryptic causes of queen failure. Further work will be necessary to determine how long after the stress event a marker's expression remains elevated, and how accurate these markers will be for field diagnoses.


Assuntos
Praguicidas , Abelhas , Biomarcadores
13.
Mol Hum Reprod ; 25(12): 787-796, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31651026

RESUMO

Peroxiredoxins (PRDXs) are antioxidant enzymes proven to control the levels of reactive oxygen species (ROS) and to avoid oxidative damage in the spermatozoon. Previously, we have shown that low amounts of PRDXs are associated with male infertility and that PRDX6 is the primary antioxidant defense in human spermatozoa, maintaining survival and DNA integrity (Gong et al., 2012, Fernandez and O'Flaherty, 2018). Oxidative stress can trigger different pathway cascades in the spermatozoa, including truncated apoptosis. It has been reported that the phosphorylation status of phosphoinositide 3-kinase (PI3K) and its target AKT (protein kinase B) prevent the spermatozoon from entering the truncated apoptotic cascade. Here, we aim to study the regulation of the PI3K/AKT pathway by PRDX6 and assess its role in maintaining sperm viability. Human semen samples were obtained over 1 year from 20 healthy non-smoking volunteers aged 22-30 years. Sperm viability, lipid peroxidation and apoptosis-like changes were determined by flow cytometry while phosphorylation of PI3K and AKT substrates were assessed by immunoblotting using anti-phospho-PI3K and anti-phospho-AKT substrates antibodies. We found that the addition of arachidonic acid and lysophosphatidic acid, products of PRDX6 calcium-independent phospholipase A2 (Ca2+-iPLA2), prevented loss of sperm viability and maintained the phosphorylation of PI3K. Antioxidant compounds such as D-penicillamine partially prevented the oxidative damage on spermatozoa that led to a reduction of their viability. Thus, other pathways can also participate in sperm survival and be regulated by PRDXs. In conclusion, PRDX6 contributes to the regulation of ROS production and the PI3K/AKT pathway for the maintenance of sperm survival.


Assuntos
Estresse Oxidativo/fisiologia , Peroxirredoxina VI/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo , Adulto , Antioxidantes/farmacologia , Apoptose/fisiologia , Ácido Araquidônico/farmacologia , Sobrevivência Celular/fisiologia , Humanos , Infertilidade Masculina/fisiopatologia , Lisofosfolipídeos/farmacologia , Masculino , Penicilamina/farmacologia , Peroxirredoxina VI/antagonistas & inibidores , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Adulto Jovem
14.
Hum Reprod ; 33(8): 1394-1407, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29912414

RESUMO

STUDY QUESTION: Are all components of the peroxiredoxins (PRDXs) system important to control the levels of reactive oxygen species (ROS) to maintain viability and DNA integrity in spermatozoa? SUMMARY ANSWER: PRDX6 is the primary player of the PRDXs system for maintaining viability and DNA integrity in human spermatozoa. WHAT IS KNOWN ALREADY: Mammalian spermatozoa are sensitive to high levels of ROS and PRDXs are antioxidant enzymes proven to control the levels of ROS generated during sperm capacitation to avoid oxidative damage in the spermatozoon. Low amounts of PRDXs are associated with male infertility. The absence of PRDX6 promotes sperm oxidative damage and infertility in mice. STUDY DESIGN, SIZE, DURATION: Semen samples were obtained over a period of one year from a cohort of 20 healthy non-smoking volunteers aged 22-30 years old. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sperm from healthy donors was incubated for 2 h in the absence or presence of inhibitors for the 2-Cys PRDXs system (peroxidase, reactivation system and NADPH-enzymes suppliers) or the 1-Cys PRDX system (peroxidase and calcium independent-phospholipase A2 (Ca2+-iPLA2) activity). Sperm viability, DNA oxidation, ROS levels, mitochondrial membrane potential and 4-hydroxynonenal production were determined by flow cytometry. MAIN RESULTS AND THE ROLE OF CHANCE: We observed a significant decrease in viable cells due to inhibitors of the 2-Cys PRDXs, PRDX6 Ca2+-iPLA2 activity or the PRDX reactivation system compared to controls (P ≤ 0.05). PRDX6 Ca2+-iPLA2 activity inhibition had the strongest detrimental effect on sperm viability and DNA oxidation compared to controls (P ≤ 0.05). The 2-Cys PRDXs did not compensate for the inhibition of PRDX6 peroxidase and Ca2+-iPLA2 activities. LARGE SCALE DATA: Not applicable. LIMITATIONS, REASONS FOR CAUTION: Players of the reactivation systems may differ among mammalian species. WIDER IMPLICATIONS OF THE FINDINGS: The Ca2+-iPLA2 activity of PRDX6 is the most important and first line of defense against oxidative stress in human spermatozoa. Peroxynitrite is scavenged mainly by the PRDX6 peroxidase activity. These findings can help to design new diagnostic tools and therapies for male infertility. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by The Canadian Institutes of Health Research (MOP 133661 to C.O.), and by RI MUHC-Desjardins Studentship in Child Health Research awarded to M.C.F. The authors have nothing to disclose.


Assuntos
Dano ao DNA , Peroxirredoxina VI/metabolismo , Espermatozoides/enzimologia , Adulto , Biomarcadores/metabolismo , Sobrevivência Celular , Voluntários Saudáveis , Humanos , Peroxidação de Lipídeos , Masculino , Potencial da Membrana Mitocondrial , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Espermatozoides/patologia , Adulto Jovem
15.
Cryobiology ; 81: 145-152, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29397923

RESUMO

Addition of seminal plasma (SP) prior to cryopreservation may influence stallion sperm cryosurvival. The objective of this study was to investigate the addition of pooled SP from "good" or "bad" freezer stallions to spermatozoa selected by single layer centrifugation (SLC) prior to cryopreservation on post-thaw sperm quality. Semen from 12 stallions was collected; 5 mL was frozen as control (C) and the remainder was processed by SLC to remove SP and was divided into three aliquots: i) SLC sample without SP (SLC); ii) SLC plus pooled SP from "good freezer" stallions (SLC-GF); iii) SLC plus pooled SP from "bad freezer" stallions (SLC-BF). After thawing, the following parameters were evaluated: chromatin integrity (DNA fragmentation index; %DFI), mitochondrial membrane potential (MMP), membrane integrity (MI), reactive oxygen species (ROS) and sperm kinematics. The %DFI was reduced (P < 0.0001) in SLC samples compared to controls. The SLC group showed a lower proportion of spermatozoa with low MMP and a higher proportion of spermatozoa with high MMP than other groups (P < 0.0001), and had lower hydrogen peroxide content than control. Sperm kinematics were not different. In conclusion, selection by SLC prior to cryopreservation improved post-thaw sperm quality; inclusion of SP from "good" and "bad" freezer stallions did not have an additional beneficial effect.


Assuntos
Criopreservação/veterinária , Preservação do Sêmen/veterinária , Sêmen , Animais , Centrifugação , Congelamento , Cavalos , Masculino
16.
Zygote ; 26(4): 286-293, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30210017

RESUMO

SummaryThe aim of this study was to optimize protocols for electroporation (EP) and polyfection (PLF) using polyethyleneimine (PEI) for pig sperm transfection and to determine which method was the most efficient. For EP standardization, different voltages, amounts and times of electric pulses were tested using propidium iodide (PI) as reporter. For PLF standardization, different concentrations of fluorescein isothiocyanate (FITC)-labelled PEI (PEI/FITC) were incubated with sperm for different periods of time. Flow cytometry was performed to evaluate the best protocol in terms of cell viability, including cytoplasmic membrane, acrosome, chromatin integrities and mitochondrial potential using the FITC probe, PI, acridine orange (AO) and JC1. Transfections with the plasmid pmhyGENIE-5 were carried out under optimum conditions for each procedure (EP: 500 volts, 500 µs and two pulses; PLF: PEI 0.5 mg/ml and incubation time 10 min). Transfection efficacy was assessed by fluorescence in situ hybridization (FISH). A lower transfection rate was observed for sperm in the control group (17.8%) compared with EP (36.7%), with PLF (76.8%) being the most efficient. These results suggest that the EP and PEI could be an efficient and low cost transfection method for swine sperm. Notably, treated cells showed higher plasmatic the membrane damage (PMD) and/or acrosome damage (AD) indexes, therefore the combination of this procedure with biotechniques that facilitate fecundation (i.e. in vitro fertilization or intracytoplasmic sperm injection) or even inclusion of antioxidant or anti-apoptotic drugs to improve spermatozoa viability would be important.


Assuntos
Eletroporação/veterinária , Polietilenoimina/química , Preservação do Sêmen/veterinária , Espermatozoides/citologia , Transfecção/veterinária , Animais , Sobrevivência Celular , Fertilização in vitro , Masculino , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Suínos
17.
Andrologia ; 50(1)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28488738

RESUMO

The use of frozen semen for artificial insemination is the main approach utilised for the genetic improvement of most domesticated species. The advantages include lower transportation costs, continuous availability of semen, fewer occurrences of sexually transmitted diseases and the incorporation of desirable genes in a relatively short amount of time. Nevertheless, the use of frozen semen in buffalo herds remains limited due to the loss of sperm quality when buffalo semen is frozen. So, the goal of this study was to evaluate the pre- and post-cryopreservation quality of buffalo semen diluted in three distinct freezing media: Tris-egg yolk, Botu-bov® (BB) and ACP-111®. Thirty-two ejaculates from four bulls were analysed in terms of kinetics, morphology and sperm viability by epifluorescence microscope. Thawed samples were also evaluated for capacitation-like damage, DNA fragmentation and plasma and acrosomal membrane integrity using flow cytometry. The Tris-egg yolk and BB® extenders yielded better results than the ACP-111® extender for kinetics parameter (total motility, progressive motility and percentage of rapid cells). However, semen samples were similar for parameters evaluated by flow cytometry. Taken together, the data indicate that in comparison with Tris-egg yolk and BB extender, ACP-111® can also be used as an extender for buffalo semen cryopreservation.


Assuntos
Criopreservação/veterinária , Crioprotetores , Preservação do Sêmen/veterinária , Animais , Búfalos , Criopreservação/métodos , Inseminação Artificial/veterinária , Masculino , Sêmen , Análise do Sêmen , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides
18.
Reprod Domest Anim ; 53(1): 26-33, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28891229

RESUMO

Straws of sex-sorted sperm are usually packaged at a low concentration (e.g., ~2.1 × 106  sperm/ml) and cost significantly more than unsorted conventional semen from the same sire. In order to maximize the efficiency of using sex-sorted sperm under in vitro fertilization conditions, the selection of an appropriate sperm separation technique is essential. In this study, the effect of using different silane-coated silica colloid dilutions and layering configurations during centrifugation of sex-sorted sperm was examined over an extended period of incubation time. Sperm recovery and viability after centrifugation using the colloid separation technique were measured along with several sperm motility parameters using CASA. For this purpose, frozen and thawed sex-sorted sperm samples were centrifuged using mini-volume single-layer (40%, 60% and 80%) and mini-volume two-layer (45%/90%, 40%/80% and 30%/60%) separation configurations using PureSperm® . A single layer of 40% PureSperm® recovered significantly more sex-sorted sperm (78.07% ± 2.28%) followed by a single layer of 80% PureSperm® (68.43% ± 2.33%). The lowest sperm recovery was obtained using a two-layer PureSperm® dilution of 45%/90% (47.57% ± 2.33%). Single-layer centrifugation recovered more sorted sperm (68.67% ± 1.74%) than two layer (53.74% ± 1.74%) (p < .0001). A single layer of 80% PureSperm® exhibited the highest sorted sperm viability (72.01% ± 2.90%) after centrifugation (p < .05). The mini-volume single layer of 80% PureSperm® was determined to be an effective alternative to a two-layer centrifugation configuration for sex-sorted sperm selection. In addition, single-layer colloid dilution of 80% performed either as well as or significantly outperformed the other treatments, as well as the control, with regard to motility (MOT) for all time periods of analysis.


Assuntos
Centrifugação/veterinária , Espermatozoides/fisiologia , Animais , Bovinos , Centrifugação/métodos , Coloides/farmacologia , Criopreservação/métodos , Criopreservação/veterinária , Citometria de Fluxo/veterinária , Processamento de Imagem Assistida por Computador , Masculino , Análise do Sêmen/métodos , Análise do Sêmen/veterinária , Pré-Seleção do Sexo/veterinária
19.
Reprod Domest Anim ; 52 Suppl 4: 69-71, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29052326

RESUMO

The presence of bacteria adversely affects boar sperm quality of seminal doses intended for artificial insemination. Currently, the most common measure to prevent bacteriospermia is the addition of antibiotics in semen extenders; however, mounting evidence shows that microbial resistance exists. A promising alternative to replace antibiotics are antimicrobial peptides. In this study, the effects of the antimicrobial peptide protegrine 1 (PG1) on the sperm viability and bacterial load of boar seminal doses were evaluated. Three different concentrations of PG1 (2.5, 25 and 100 µg/ml) were tested over a storing period of 10 days at 17°C. Sperm viability was analysed by fluorescence microscopy (SYBR14/propidium iodide), and bacterial load was assessed by plating 100 µl of each sample in Luria-Bertani medium and incubated at 37°C for 72 hr under aerobic conditions. Protegrine 1 was effective in controlling the bacterial load in all the assessed concentrations (p < .05), reaching the lowest values at the highest concentrations of the antimicrobial peptide. Nevertheless, sperm viability was significantly (p < .05) reduced by all tested concentrations of this peptide, the most cytotoxic effects being observed at the highest PG1 concentrations. Despite these results, the use of PG1 as an alternative to antibiotics cannot be totally discarded, as further studies using the truncated form of this peptide are needed.


Assuntos
Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Espermatozoides/efeitos dos fármacos , Suínos , Animais , Anti-Infecciosos/efeitos adversos , Peptídeos Catiônicos Antimicrobianos/efeitos adversos , Carga Bacteriana/veterinária , Masculino , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Espermatozoides/microbiologia
20.
Pharm Biol ; 55(1): 2035-2042, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28836479

RESUMO

CONTEXT: Terminalia chebula Retz (Combretaceae) and Musa balbisiana Colla (Musaceae) have a traditional reputation as a male contraceptive. OBJECTIVE: To determine the hypo-testicular activity of aqueous extracts of Terminalia chebula (fruit) and Musa balbisiana (seed) separately, and in composite manner at the ratio of 1:1 named as 'Contracept-TM' compared to cyproterone acetate (CPA), for developing a polyherbal contraceptive. MATERIALS AND METHODS: The separate extract of above said plants or 'Contracept-TM' at the dose of 40 mg/100 g body weight of rat/day or CPA at 2 mg/100 g body weight of rat/day was administered for 28 days. Spermiological, androgenic and oxidative stress sensors, LD50 and ED50/100 g body weight values were measured. RESULTS: Treatment of individual, 'Contracept-TM' or CPA resulted significant decrease in the count of spermatogonia A (36.36-49.09%), pre-leptotene spermatocyte (19.11-55.30%), mid-pachytene spermatocyte (28.65-47.28%) and step 7 spermatid (29.65-51.59%). Activities of testicular Δ5, 3ß (21.25-48.02%),17ß-hydroxysteroid dehydrogenases (29.75-55.08%), catalase (19.06-43.29%) and peroxidase (30.76-62.82%), levels of testosterone (28.15-63.44%), testicular cholesterol (19.61-49.33%), conjugated diene (29.69-84.99%) and thiobarbituric acid reactive substances (41.25-86.73%) were elevated compare to the control. The ED50 and LD50 values were 40 mg and 5.8 g (T. chebula), 48 mg and 6.3 g (M. bulbisiana), 40 mg and 6.0 g ('Contracept-TM'), respectively. DISCUSSION AND CONCLUSION: The said spermiological and androgenic sensors' levels were decreased significantly by 'Contracept-TM' than its constitutional individual plant extract and it may be comparable to standard anti-testicular drug like CPA. So, it may be concluded that above polyherbal formulation is potent for inducing hypo-testicular activity.


Assuntos
Musa , Extratos Vegetais/farmacologia , Preparações de Plantas/farmacologia , Terminalia , Testículo/efeitos dos fármacos , Animais , Anticoncepcionais Masculinos , Frutas , Masculino , Extratos Vegetais/isolamento & purificação , Preparações de Plantas/isolamento & purificação , Ratos , Ratos Wistar/psicologia , Sementes , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/citologia , Testículo/metabolismo , Água/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA