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1.
Free Radic Biol Med ; 160: 47-56, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-32768571

RESUMO

Vitamin E is considered a powerful biological antioxidant; however, its characteristics such as high hydrophobicity and low stability limit its application. We propose to use nanotechnology as an innovative tool in spermatology, formulating nanoemulsions (NE) that accommodate vitamin E, protecting it from oxidation and promoting its release into the medium. The protective effect of the NE against oxidative stress was assessed in red deer epididymal sperm incubated at 37 °C. Cryopreserved sperm from eleven stags were thawed and extended to 400 × 106 sperm/ml in Bovine Gamete Medium (BGM). Once aliquoted, the samples were supplemented with the NE at different concentrations (0, 6 and 12 mM), with or without induced oxidative stress (100 µM Fe2+/ascorbate). The samples were evaluated after 0, 2 and 4 h of incubation at 37 °C. Motility (CASA), viability, mitochondrial membrane potential, acrosomal status, lipoperoxidation (C11 BODIPY 581/591), intracellular reactive oxygen species (ROS) production and DNA status (SCSA®) were assessed. After 2 and 4 h of incubation, the NE were able to prevent the deleterious effects of oxidative stress, thus improving total and progression motility (P ˂0.05). Moreover, the highest concentration tested (12 mM) improved almost every sperm kinematic variable (P ˂0.05) and preserved sperm viability in samples subjected to oxidative stress. In addition, 12 mM of NE protected the acrosomes integrity, maintained and protected mitochondrial activity, prevented sperm lipoperoxidation and reduced ROS production (P ˂0.05) in samples subjected to oxidative stress. This work indicates for the first time that vitamin E formulated in NE could be a new approach against sperm oxidative damage. This could be highly relevant for sperm physiology preservation in the context of assisted reproduction techniques.


Assuntos
Cervos , Nanotecnologia , Estresse Oxidativo , Motilidade dos Espermatozoides , Vitamina E , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Humanos , Masculino , Espécies Reativas de Oxigênio/metabolismo , Reprodução , Espermatozoides/metabolismo , Vitamina E/metabolismo , Vitamina E/farmacologia
2.
Theriogenology ; 144: 45-55, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31911322

RESUMO

Capacitation-like changes affect sperm of several species, such as ram, reducing cell survival and fertilizing competence. Proteins from seminal plasma stabilize sperm plasma membranes, being an interesting focus to develop strategies for improving cryopreserved ram semen performance. To date, biotechnologies are focused to reduce damage in frozen-thawed ram spermatozoa through the addition of bioactives. Serine Protease Inhibitor Kazal-type 3 (SPINK3) is a little protein synthesized by mouse seminal vesicle and secreted to seminal plasma. While attached to the sperm, this protein binds to non-capacitated sperm and blocks calcium entry, avoiding a premature physiological capacitation and consequently, acrosome reaction. Due to these characteristics, SPINK3 has been proposed as a decapacitating factor. The aim of this work was to assess whether heterologous SPINK3 is able to protect ram sperm from the well-known cell damages produced by freezing/thawing and to understand the mechanisms by which it is acting. Sperm were supplemented with 13 µM SPINK3 before freezing in an egg yolk-based extender or after thawing and selection. Under both conditions, SPINK3 decreased intracellular calcium content (p < 0.05) and reduced the 25 kDa tyrosine phosphorylated protein demonstrating a decapacitating effect, although the addition of the protein before cryopreservation was not enough to improve other sperm parameters. However, the addition of SPINK3 post thawing was able to significantly ameliorate viability, motility, mitochondrial status and to avoid the increase of lipid peroxidation (p < 0.05). Moreover, sperm treated with SPINK3 was not only still capable to fertilize, but also improved it, as evidenced by an increase in the oocyte cleavage rate (p < 0.05) although, the embryo development and embryo quality were not affected. Our findings would contribute to develop a strategy for improving sperm quality by using decapacitating proteins. In fact, the outcomes of this work demonstrate that SPINK3 is able to reduce sperm cryo-injuries when is added after thawing, improving functionality and thus in vitro fertilization results.


Assuntos
Criopreservação/veterinária , Preservação do Sêmen/veterinária , Inibidores de Serinopeptidase do Tipo Kazal/farmacologia , Ovinos/fisiologia , Espermatozoides/fisiologia , Animais , Técnicas de Cultura Embrionária , Embrião de Mamíferos , Fertilização in vitro/veterinária , Regulação da Expressão Gênica , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Análise do Sêmen , Inibidores de Serinopeptidase do Tipo Kazal/genética , Inibidores de Serinopeptidase do Tipo Kazal/metabolismo , Motilidade dos Espermatozoides
3.
Reprod Domest Anim ; 51(5): 743-50, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27491678

RESUMO

Reactive oxygen species (ROS) are fundamental for intracellular signalling. In spermatozoa, they are involved both to apoptosis and to capacitation, and changes in ROS levels can alter the balance between these two processes. Oestrous sheep serum (OSS) is considered an efficient agent for in vitro capacitation of ram spermatozoa. We have explored the effects of OSS on ram sperm physiology, especially on ROS production, during in vitro capacitation. Semen samples from 15 rams were cryopreserved. After thawing, samples were submitted to four treatments: control (CTL), 10% OSS supplementation for in vitro sperm capacitation, caspase inhibitor (INH, Z-VAD-FMK 100 µM) and OSS (10%) plus caspase inhibitor (I + E). Sperm samples were incubated for 30 min at 38.5°C and 5% CO2 and evaluated motility and kinetic parameters by computer-assisted semen analysis (CASA) and viability (propidium iodide), apoptotic-like membrane changes (YO-PRO-1), acrosomal status (PNA-FITC), intracellular calcium (FLUO-3), membrane fluidity (M540) and ROS production (CM-H2 DCFDA) by flow cytometry. OSS induced changes in kinetic parameters compatible with capacitation, with a decrease in the percentage of progressive motility and linearity, and an increase in the amplitude of the lateral displacement of the sperm head (p < .05). Moreover, OSS increased the proportion of M540+ viable spermatozoa, YO-PRO-1+ and acrosome-reacted spermatozoa (p < .05). After incubation, OSS and I+E achieved lower ROS levels (p < .05). Ca(2+) levels did not change with the incubation, but were slightly higher (p < .05) when both OSS and the inhibitor were present. We suggest that OSS may modulate ROS levels, allowing intracellular signalling for capacitation to occur while preventing higher levels that could trigger apoptosis.


Assuntos
Estro/sangue , Ovinos/sangue , Ovinos/fisiologia , Capacitação Espermática/fisiologia , Espermatozoides/fisiologia , Animais , Caspases/farmacologia , Estro/fisiologia , Feminino , Masculino , Espécies Reativas de Oxigênio , Motilidade dos Espermatozoides
4.
Anim Reprod Sci ; 162: 73-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26474690

RESUMO

The potential protective effect of reduced glutathione (GSH) and trolox (TRX), an analogue of vitamin E, supplementation during in vitro culture (2h, 39°C) of electroejaculated frozen/thawed red deer sperm was investigated. Cryopreserved sperm were thawed and incubated with no additive (Control) and 1mM or 5mM of each antioxidant to find out whether these supplementations can maintain the sperm quality, considering the use of thawed samples for in vitro techniques such as in vitro fertilisation (IVF), sperm sex sorting or refreezing. The effect of GSH on sperm motility was positive compared to TRX which was negative (P<0.001). After 2h of incubation at 39°C, use of GSH improved motility while TRX supplementation reduced sperm motility compared with Control samples without antioxidant. Use of TRX at both concentrations (1 and 5mM; TRX1 and TRX5) resulted in lesser percentages of apoptotic sperm (12.4±1.1% and 11.7±0.9%) than GSH1, GSH5 (15.2±1% and 14.6±1.1%) and Control samples (16.9±1.2%) (P<0.001). Use of GSH at both concentrations (1 and 5mM) resulted in greater mitochondrial activity as compared with findings for the Control, TRX1 and TRX5 groups. Results of this study indicate that GSH is a suitable supplement for electroejaculated red deer sperm. It would be necessary to conduct fertility trials (in vivo and in vitro), to assess whether GSH supplementation of thawed red deer sperm could improve fertility rates.


Assuntos
Criopreservação/veterinária , Crioprotetores/farmacologia , Glutationa/farmacologia , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Animais , Fenômenos Biomecânicos , Cromanos/farmacologia , Criopreservação/métodos , Cervos , Citometria de Fluxo/veterinária , Masculino , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos
5.
Anim Reprod Sci ; 135(1-4): 37-46, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23021747

RESUMO

The use of assisted reproductive techniques in cervids is increasing as the commercial use of these species increase. We have tested the suitability of the antioxidants Trolox and reduced glutathione (GSH) for freezing red deer epididymal spermatozoa, aiming at improving post-thawing quality. Samples from 19 stags were frozen in a TES-Tris-fructose extender (20% egg yolk, 8% glycerol), with 1 or 5 mM of antioxidant. Motility (CASA), lipoperoxidation (malondialdehyde -MDA- production), membrane status, mitochondrial activity, acrosomal status (flow cytometry) and chromatin status (SCSA: %DFI and %HDS; flow cytometry) were assessed after thawing and after 6 h at 39°C. There were few differences between treatments after thawing, with Trolox reducing MDA production in a dose-response manner. After the incubation, sperm quality decreased and %DFI increased moderately, with no change for MDA. GSH improved motility, kinematic parameters and mitochondrial status, with a slight increase in %HDS. GSH 5 mM also increased moderately MDA production and %DFI, possibly due to enhanced metabolic activity and reducing power. Trolox maintained MDA low, but was detrimental to sperm quality. Trolox might not be appropriate for the cryopreservation of red deer epididymal spermatozoa, at least at the millimolar range. GSH results are promising, especially regarding motility improvement after the post-thawing incubation, and should be selected for future fertility trials.


Assuntos
Cromanos/farmacologia , Criopreservação/veterinária , Cervos/fisiologia , Epididimo/fisiologia , Glutationa/farmacologia , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Reação Acrossômica/fisiologia , Animais , Membrana Celular/fisiologia , Cromatina/fisiologia , Criopreservação/métodos , Citometria de Fluxo/veterinária , Masculino , Malondialdeído/análise , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/fisiologia
6.
Theriogenology ; 78(5): 1005-19, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22818091

RESUMO

Antioxidants may be useful for supplementing sperm extenders. We have tested dehydroascorbic acid (DHA), TEMPOL, N-acetyl-cysteine (NAC) and rutin on epididymal spermatozoa from red deer, during incubation at 37 °C. Cryopreserved spermatozoa were thawed, washed and incubated with 1 mM or 0.1 mM of each antioxidant, including oxidative stress (Fe(2+)/ascorbate). Motility (CASA and clustering of subpopulations), viability, mitochondrial membrane potential, and acrosomal status were assessed at 2 and 4 h. Lipoperoxidation, intracellular reactive oxygen species (ROS) and DNA damage (DNA) status (TUNEL) were checked at 4 h. Oxidative stress increased ROS, lipoperoxidation and DNA damage. Overall, antioxidants negatively affected motility and physiological parameters. Only DHA 1 mm protected motility, increasing the fast and progressive subpopulation. However, it had a detrimental effect on acrosomal and DNA status, in absence of oxidative stress. Tempol and rutin efficiently reduced lipoperoxidation, ROS, and DNA damage in presence of oxidative stress. NAC was not as efficient as TEMPOL or rutin reducing lipoperoxidation or protecting DNA, and did not reduce ROS, but its negative effects were lower than the other antioxidants when used at 1 mm, increasing the subpopulation of hyperactivated-like spermatozoa at 2 h. Our results show that these antioxidants have mixed effects when spermatozoa are incubated at physiological temperatures. DHA may not be suitable because of prooxidant effects, but TEMPOL, NAC and rutin may be considered for cryopreservation trials. In general, exposure of red deer spermatozoa to these antioxidants should be limited to low temperatures, when only protective effects may develop.


Assuntos
Fragmentação do DNA , Cervos , Preservação do Sêmen/métodos , Espermatozoides/fisiologia , Animais , Antioxidantes/farmacologia , Biomarcadores , Congelamento , Peroxidação de Lipídeos , Masculino , Malondialdeído , Estresse Oxidativo , Espécies Reativas de Oxigênio , Temperatura
7.
Allergol. immunopatol ; 40(3): 138-143, mayo-jun. 2012. tab, graf
Artigo em Inglês | IBECS | ID: ibc-99341

RESUMO

Background: Good control of allergic rhinitis (AR) in children is desirable because it is associated with diseases such as asthma. The aim of this analysis of the PETRA study was to characterize its diagnosis and treatment in Spanish children. Methods: Data were analysed for paediatric patients (age 5-17 years, inclusive) included in the PETRA study, which included consecutive patients with allergic rhinitis attending respiratory specialists throughout Spain. Demographic information, disease characteristics (duration, severity according to the Allergic Rhinitis and its Impact on Asthma [ARIA] classification), diagnostic procedures, treatments and physicians’ attitudes to treatment were recorded. Results: Of the original sample of 1043 patients, 260 children were included (mean age, 11.7 years; 56.2% boys; 61.9% allergic to house dust mites (HDM) and 38.1% allergic to grass pollen). By ARIA classification, 180/260 (69.4%) had persistent AR and 176/280 (63%) had moderate disease. Asthma was reported in 89/161 (55%) with HDM allergy and 44/99 (45%) with grass pollen allergy. Symptomatic treatment was prescribed in 98.5%, although disease control had been no better than poor in 57.3%. Allergen specific immunotherapy was administered to 56.9%, and was used more often for HDM AR. When asked why specific immunotherapy was not prescribed, two-thirds of the investigators preferred a wait-and-see approach, prescribing immunotherapy if symptoms worsened or asthma developed. Conclusions: Paediatric patients treated by specialists for allergic rhinitis have moderate or severe disease. Symptomatic treatment was extensively prescribed but often did not achieve good disease control. Many specialists preferred a wait-and-see approach before prescribing immunotherapy(AU)


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Rinite Alérgica Perene/diagnóstico , Rinite Alérgica Perene/terapia , Asma/prevenção & controle , Pyroglyphidae/patogenicidade , Pólen/efeitos adversos , Índice de Gravidade de Doença , Estudos Epidemiológicos
8.
Reprod Domest Anim ; 44(2): 212-20, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18992076

RESUMO

We have approached the problem of refrigerated storage of epididymal sperm samples from red deer by comparing three options: storing the genital (testicles within the scrotum), diluting the semen in extender or diluting the semen in extender supplemented with an anti-oxidant. Twenty-nine pairs of testes were collected. Spermatozoa from one of each of the pairs were immediately recovered, and diluted to 400 x 10(6) sperm/ml in Tris-citrate-fructose with 20% egg yolk. Control group was stored as such, and Anti-oxidant group was supplemented with 0.8 mm vitamin C. The remaining epididymides and the diluted samples were stored at 5 degrees C and spermatozoa were analysed at 0, 24, 96 and 192 h for: motility [computer-assisted semen analysis (CASA)], acrosomal integrity, sperm viability (eosine/nigrosine staining), normal tails and chromatin status [sperm chromatin structure assay (SCSA)]. In general, seminal quality decreased with storage time. Vitamin C supported progressive motility better at 24 h (median 42% vs 23% Control and 15% epididymis), reduced the incidence of tail abnormalities and protected chromatin. Storing the semen in the epididymis slowed down motility loss, but slightly increased the occurrence of tail abnormalities and viability was lower at 192 h. However, regarding chromatin status, sperm stored in the epididymis was protected similarly to those diluted in the medium supplemented with vitamin C. Although the differences between the three groups were small, there were some advantages in supplementing the extender with vitamin C. Besides, refrigerating the epididymis may be a good option when immediate processing is not available.


Assuntos
Ácido Ascórbico/administração & dosagem , Temperatura Baixa , Cervos/fisiologia , Epididimo/citologia , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Acrossomo/ultraestrutura , Animais , Antioxidantes/administração & dosagem , Sobrevivência Celular , Processamento de Imagem Assistida por Computador , Masculino , Preservação do Sêmen/métodos , Soluções , Motilidade dos Espermatozoides , Cauda do Espermatozoide/ultraestrutura , Espermatozoides/ultraestrutura
9.
Int J Androl ; 32(4): 353-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18298570

RESUMO

The potential protective effect of catalase supplementation during in vitro culture of frozen/thawed bull spermatozoa was investigated. Frozen/thawed semen collected from three fighting bulls was diluted in phosphate buffered saline (PBS) and incubated at 37 degrees C under different experimental conditions: Control, Catalase (CAT) (200 U/mL), Oxidant (OXI) (100 microm Fe(2+)/1 mm ascorbate), and Catalase + Oxidant (CAT/OXI). We assessed sperm motility, acrosomal integrity, viability and chromatin status (SCSA) at 0, 2 and 6 h of incubation. Our results showed that catalase abolished the effect of the oxidant, protecting spermatozoa against reactive oxygen species, and improving both sperm motility and chromatin status during incubation. The OXI treatment significantly reduced the percentage of motile sperm after 6 h of incubation. The statistical model also showed that there were differences in sperm motility between CAT/OXI (20.8 +/- 2.9%) and OXI (11.6 +/- 7.6%) (p < 0.001). There were no significant effects of OXI on sperm viability, acrosomal status or proportion of abnormal tails. %DFI (spermatozoa with moderate or high DNA Fragmentation Index) was significantly higher on OXI (p < 0.001). Catalase prevented DNA fragmentation even in the presence of the oxidant (%DFI: 30.3 +/- 0.8% OXI vs. 17.4 +/- 0.7% CAT/OXI). We conclude that catalase supplementation after thawing could protect bull spermatozoa against oxidative stress, and it could improve media used for processing thawed spermatozoa.


Assuntos
Antioxidantes/farmacologia , Catalase/farmacologia , Criopreservação , Dano ao DNA/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Preservação do Sêmen , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Acrossomo/efeitos dos fármacos , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Espermatozoides/metabolismo , Espermatozoides/patologia , Fatores de Tempo
10.
Allergol Immunopathol (Madr) ; 33(2): 100-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15808117

RESUMO

BACKGROUND: Sensitivity to Salsola kali is a frequent cause of allergic respiratory disease in various regions of Spain. However, there are very few articles in which this allergen has been studied. METHODS AND RESULTS: In order to evaluate the tolerance of this extract, a prospective study has been performed. This study was observational, multi-centred and open, involving 88 patients with allergic respiratory disease due to sensitivity to Salsola, aged between 5 and 52 years. The administration of the extract was performed subcutaneously, through one of two treatment schedules: cluster (8 doses in 4 visits) or conventional (13 doses in 12 visits). A total of 42 adverse reactions were registered, in 26 patients (35 local reactions in 21 patients and 7 systemic reactions in 6 patients). Among the 7 systemic reactions, 4 were registered with the cluster protocol and 2 with the conventional protocol (p = 0.329). In no patients were serious adverse reactions registered. CONCLUSION: The subcutaneous administration of a Salsola extract is safe and well tolerated, both when administered using a conventional schedule and when using a cluster schedule.


Assuntos
Asma/terapia , Dessensibilização Imunológica/efeitos adversos , Hipersensibilidade a Drogas/etiologia , Extratos Vegetais/efeitos adversos , Rinite Alérgica Sazonal/terapia , Salsola/imunologia , Adolescente , Adulto , Asma/etiologia , Criança , Pré-Escolar , Dessensibilização Imunológica/métodos , Eczema/induzido quimicamente , Feminino , Febre/induzido quimicamente , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/administração & dosagem , Extratos Vegetais/normas , Extratos Vegetais/uso terapêutico , Estudos Prospectivos , Rinite Alérgica Sazonal/etiologia , Urticária/induzido quimicamente
11.
Allergol. immunopatol ; 33(2): 100-104, mar. 2005. tab
Artigo em En | IBECS | ID: ibc-037686

RESUMO

Background: Sensitivity to Salsola kali is a frequent cause of allergic respiratory disease in various regions of Spain. However, there are very few articles in which this allergen has been studied. Methods and Results: In order to evaluate the tolerance of this extract, a prospective study has been performed. This study was observational, multi-centred and open, involving 88 patients with allergic respiratory disease due to sensitivity to Salsola, aged between 5 and 52 years. The administration of the extract was performed subcutaneously, through one of two treatment schedules: cluster (8 doses in 4 visits) or conventional (13 doses in 12 visits). A total of 42 adverse reactions were registered, in 26 patients (35 local reactions in 21 patients and 7 systemic reactions in 6 patients). Among the 7 systemic reactions, 4 were registered with the cluster protocol and 2 with the conventional protocol (p = 0.329). In no patients were serious adverse reactions registered. Conclusion: The subcutaneous administration of a Salsola extract is safe and well tolerated, both when administered using a conventional schedule and when using a cluster schedule


Antecedentes: La sensibilización a Salsola kali es una causa frecuente de enfermedad alérgica respiratoria en varias zonas de España. Sin embargo, apenas existen publicaciones en las que se estudie este alergeno. Métodos y resultados: Para valorar la tolerancia de este extracto, se ha realizado un estudio prospectivo, observacional, multicéntrico y abierto, en el que se han incluido 88 pacientes, de edad entre 5 y 52 años, con enfermedad alérgica respiratoria por sensibilización a Salsola. La administración del extracto se ha realizado por vía subcutánea, mediante dos esquemas de tratamiento: agrupada (8 dosis en 4 visitas) o convencional (13 dosis en 12 visitas). Se han registrado un total de 42 reacciones adversas en 26 pacientes (35 locales en 21 pacientes y 7 sistémicas en 6 pacientes). De las 7 reacciones sistémicas, 4 se registraron con la pauta agrupada y 2 con la convencional (p = 0,329). No se registró ninguna reacción adversa grave. Conclusión: La administración subcutánea de un extracto de Salsola es segura y bien tolerada, tanto cuando se administra con una pauta convencional como con una pauta agrupada


Assuntos
Criança , Adulto , Humanos , Asma/terapia , Dessensibilização Imunológica/efeitos adversos , Hipersensibilidade a Drogas/etiologia , Extratos Vegetais/efeitos adversos , Salsola/imunologia , Rinite Alérgica Sazonal/terapia , Asma/etiologia , Dessensibilização Imunológica/métodos , Febre/induzido quimicamente , Injeções Subcutâneas , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Urticária/induzido quimicamente , Rinite Alérgica Sazonal/etiologia
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