Resumo

Sperm quality is essential to guarantee the success of assisted reproduction. However, selecting high-quality sperm and maintaining it during (cryo)preservation for high efficiency remains challenging in livestock reproduction. A comprehensive understanding of sperm biology allows for better assessment of sperm quality, which could replace conventional sperm analyses used today to predict fertility with low accuracy. Omics approaches have revealed numerous biomarkers associated with various sperm phenotypic traits such as quality, survival during storage, freezability, and fertility. At the same time, nanotechnology is emerging as a new biotechnology with high potential for use in preparing sperm intended to improve reproduction in livestock. The unique physicochemical properties of nanoparticles make them exciting tools for targeting (e.g., sperm damage and sexing) and non-targeting bioapplications. Recent advances in sperm biology have led to the discovery of numerous biomarkers, making it possible to target specific subpopulations of spermatozoa within the ejaculate. In this review, we explore potential biomarkers associated with sperm phenotypes and highlight the benefits of combining these biomarkers with nanoparticles to further improve sperm preparation and technology.(AU)

Resumo

Cadmium (Cd) is an environmental pollutant affecting various tissues and organs, including the testis. Many studies demonstrated that Cd toxicity causes testicular impairment through oxidative stress and inflammatory action. Therefore, this study aimed to demonstrate Cd's testicular toxicity and the protective action of zeolite against cadmium's deleterious effects. Adult male rats were given Cd at a dose of 30mg/kg/day for 28 consecutive days with or without zeolite, which was given at a dose of 100mg/kg/day for 28 days. Testis weight, sperm (count, motility, and abnormalities), serum testosterone and luteinizing hormone (LH), testicular enzymes Acid phosphatase (ACP) and Alkaline phosphatase(ALP), inflammatory cytokines Tumor Necrosis Factor Alpha (TNF-α) , interleukin-1beta (IL-1ß) , and Nuclear Factor Kappa B (NF-κB) and oxidative stress were evaluated. Herein, we found that cadmium caused alterations in sperm characteristics, sex hormone disturbance, decline in testicular enzymes, elevated malondialdehyde (MDA) contents, decreased glutathione (GSH), increased Nuclear Factor Kappa B (NF-κB) and pro-inflammatory cytokines Tumor Necrosis Factor Alpha (TNF-α) and interleukin-1beta (IL-1ß) levels in testis homogenate. In contrast, zeolite significantly amended these deleterious effects, and the potential mechanism involved the downregulation of Nuclear Factor Kappa B (NF-κB), Tumor Necrosis Factor Alpha (TNF-α) and interleukin-1beta (IL-1ß), restoring glutathione (GSH) and reducing malondialdehyde (MDA). Also, zeolite was associated with an increased rate of pregnancy. Our data suggested that oxidative stress and inflammation are responsible for Cd-induced testicular injury and co-administration of zeolite exerts a protective effect via NF-κB /TNF-α/IL-1ß pathway.

O cádmio (Cd) é um poluente ambiental que afeta vários tecidos e órgãos, inclusive o testículo. Muitos estudos demonstraram que a toxicidade do Cd causa comprometimento testicular por meio de estresse oxidativo e ação inflamatória. Portanto, este estudo teve como objetivo demonstrar a toxicidade testicular do Cd e a ação protetora da zeólita contra os efeitos deletérios do cádmio. Ratos machos adultos receberam Cd em uma dose de 30mg/kg/dia por 28 dias consecutivos com ou sem zeólita, que foi administrada em uma dose de 100mg/kg/dia por 28 dias. Foram avaliados o peso dos testículos, os espermatozoides (contagem, motilidade e anormalidades), a testosterona sérica e o hormônio luteinizante (LH), as enzimas testiculares fosfatase ácida (ACP) e fosfatase alcalina (ALP), as citocinas inflamatórias fator de necrose tumoral alfa (TNF-α), interleucina-1beta (IL-1ß) e fator nuclear Kappa B (NF-κB) e estresse oxidativo. Aqui, descobrimos que o cádmio causou alterações nas características dos espermatozoides, distúrbios nos hormônios sexuais, declínio nas enzimas testiculares, conteúdo elevado de malondialdeído (MDA), diminuição da glutationa (GSH), aumento do fator nuclear Kappa B (NF-κB) e níveis de citocinas pró-inflamatórias do fator de necrose tumoral alfa (TNF-α) e interleucina-1beta (IL-1ß) no homogenato do testículo. Em contraste, a zeólita alterou significativamente esses efeitos deletérios, e o mecanismo em potencial envolveu a regulação negativa do Fator Nuclear Kappa B (NF-κB), do Fator de Necrose Tumoral Alfa (TNF-α) e da interleucina-1beta (IL-1ß), restaurando a glutationa (GSH) e reduzindo o malondialdeído (MDA). Além disso, a zeólita foi associada a uma maior taxa de gravidez. Nossos dados sugerem que o estresse oxidativo e a inflamação são responsáveis pela lesão testicular induzida por Cd e que a administração conjunta de zeólita exerce um efeito protetor por meio da via NF-κB /TNF-α/IL-1ß.

Resumo

Cryoprotectants are required to reduce damage caused to the cells due to low temperatures during the cryopreservation. Antifreeze proteins (AFP) have a well-known role in cell membrane protection, while resveratrol is a potent antioxidant. This study assessed the effect of the association of resveratrol concentrations and AFP I in a ram semen extender. Pooled semen of four rams was allocated into six treatments in a factorial arrangement: (CONT, only the semen extender); only AFP I (ANT: 0.1 µg/mL of AFP I), only resveratrol, one treatment with two levels (10 µM/mL or 50 µM/mL of resveratrol); and two treatments with the interactions, with one AFP I and one of the two levels of resveratrol (0.1 µg/mL of AFP I with 10 µM/mL resveratrol; 0.1 µg/mL of AFP I with 50 µM/mL resveratrol). No interaction between factors was observed on sperm kinetics, plasma membrane integrity, hypo-osmotic test, and mitochondrial activity parameters. There was a high probability (P = 0.06) of reducing sperm cells with functional membrane percentage in the hypo-osmotic test and increasing the percentage of sperm with high mitochondrial activity (P = 0.07) was observed in AFP presence. An interaction of AFP and resveratrol was observed in non-capacitated sperm (P = 0.009), acrosomal reaction (P = 0.034), and sperm binding (P = 0.04). In conclusion, the association of resveratrol and AFP did not improve the quality of frozen-thawed semen and even promoted deleterious effects compared to their single addition in the semen extender. The supplementation of 50 µM/mL of resveratrol improved the outcomes of frozen-thawed ram sperm, being a potential cryoprotectant.(AU)

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In 2015-2016, the Zika virus (ZIKV) caused a major epidemic in the Americas, increasing cases of microcephaly and Guillain-Barré syndrome. During this period, the discovery of ZIKV sexual transmission intensified studies on the impact of this virus on the reproductive organs. For this study, 2-month-old male BALB/c mice were infected with 1.26 x 106 PFU/mL of ZIKV in solution via the intravenous route. After three, seven, and fourteen days post-infection (DPI), blood and testicle samples were obtained to detect ZIKV RNA. The authors observed that the infected animals had slower weight gain than the control group. Viremia occurred only at 3DPI, and the ZIKV RNA was detected in one testis sample at 7DPI. The histopathological analysis of this organ revealed intense disorganization of the seminiferous tubules' structure, inflammatory infiltrate, necrosis, hemorrhage, fluid accumulation, congestion of blood vessels, and reduced sperm count. Ultrastructural analysis showed nuclear changes in tubule cells, activation of interstitial cells, and morphological changes in spermatozoa, in addition to fragmentation and decreased electron density of the genetic material of these cells. Thus, despite causing predominantly asymptomatic infections, ZIKV can cause significant subclinical and transient damage, including to male reproductive organs.(AU)

Resumo

Abstract The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.

Resumo O armazenamento a frio de leite implica potenciais alterações em sua qualidade, pois gera como processo principal radicais livres que provocam danos aos lipídios da membrana dos espermatozoides, com as consequentes alterações na motilidade e na capacidade de fertilização. Para diminuir os danos causados pelos radicais livres, as células têm defesas antioxidantes (proteínas, enzimas e substâncias de baixo peso molecular). O presente estudo avaliou o efeito do tempo de armazenamento e diferentes antioxidantes preparados em diluentes espermáticos no armazenamento de viabilidade de O. mykiss milt a 4°C. A ANOVA de duas vias denotou que o armazenamento no tempo e a influência antioxidante têm efeitos significativos separados ou combinados nos parâmetros de viabilidade (motilidade espermática, viabilidade espermática, concentrações de proteínas e atividade enzimática da superóxido dismutase no plasma seminal), enquanto apenas o tempo de armazenamento afetou a capacidade de fertilização e atividade enzimática da catalase no plasma seminal. A análise resultante pode concluir que a presença de antioxidante melhora a viabilidade do leite frio, especialmente as condições de transporte, e os antioxidantes permitem a fecundidade apesar da diminuição da motilidade.

Resumo

Purpose: The aim of this study was to determine the protective and antioxidative effects of intensive exercise on streptozotocin (STZ)-induced testicular damage, apoptotic spermatognial cells death, and oxidative stress. Methods: 36 male Sprague Dawley rats were divided into three groups: control, diabetes, and diabetes+intensive exercise (IE) groups. Testicular tissues were examined histopathologically and antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) activity, as well as serum testosterone level, were measured. Results: Seminiferous tubules and germ cells were found to be better in the testis tissue of the intense exercise group than in the diabetes group. Diabetes suppressed antioxidant enzymes CAT, SOD, GPx and testosterone levels were significantly decreased, and increased MDA level in the diabetic group compared to diabetes+IE group (p < 0.001). Following four weeks of treatment, intensive exercise improved the antioxidant defense, significantly decreased MDA activity, and increased testosterone levels in testicular tissue in the diabetic group compared to diabetes+IE group (p < 0.01). Conclusion: STZ-induced diabetes causes damage to the testis tissue. In order to prevent these damages, exercise practice has become very popular nowadays. In present study, our intensive exercise protocol, histological, and biochemical analysis of the effect of diabetes on the testicular tissues is shown.

Resumo

Abstract The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.

Resumo O armazenamento a frio de leite implica potenciais alterações em sua qualidade, pois gera como processo principal radicais livres que provocam danos aos lipídios da membrana dos espermatozoides, com as consequentes alterações na motilidade e na capacidade de fertilização. Para diminuir os danos causados pelos radicais livres, as células têm defesas antioxidantes (proteínas, enzimas e substâncias de baixo peso molecular). O presente estudo avaliou o efeito do tempo de armazenamento e diferentes antioxidantes preparados em diluentes espermáticos no armazenamento de viabilidade de O. mykiss milt a 4°C. A ANOVA de duas vias denotou que o armazenamento no tempo e a influência antioxidante têm efeitos significativos separados ou combinados nos parâmetros de viabilidade (motilidade espermática, viabilidade espermática, concentrações de proteínas e atividade enzimática da superóxido dismutase no plasma seminal), enquanto apenas o tempo de armazenamento afetou a capacidade de fertilização e atividade enzimática da catalase no plasma seminal. A análise resultante pode concluir que a presença de antioxidante melhora a viabilidade do leite frio, especialmente as condições de transporte, e os antioxidantes permitem a fecundidade apesar da diminuição da motilidade.

Resumo

In this study, it was aimed to determine the effect of sulforaphane (SFN) on rabbit semen cryopreservation. Semen collected from animals was divided into 5 equal volumes as Control, SFN 5 µM, SFN 10 µM, SFN 25 µM and SFN 50 µM groups. Afterwards, semen analyzes were performed. According to our results, there was no statistical difference between the groups at 4°C. However after freezing thawing, the highest total motility, progressive motility and rapid spermatozoa rate was seen in the 10 µM SFN group, while the lowest was observed in the 50 µM SFN group (P<0.05). Static sperm ratio was highest in the 50 µM group, while the lowest was observed in the 10 µM SFN group. When flow cytometry results examined the rate of acrosomal damaged and dead sperm was the lowest in the 10 µM SFN group, a statistical difference was observed between the control group (P<0.05). The highest rate of sperm with high mitochondrial membrane potential was seen in the 5 µM SFN and 10 µM SFN groups. Apoptosis and ROS rates were found to be lower in the experimental groups compared to the control groups (P<0.05). As a result, SFN supplementation at a dose of 10 µM increased the quality of sperm in the freezing and thawing processes of rabbit semen. In conclusion, 10 µM SFN improved the quality of cryopreservation of rabbit semen.(AU)

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ABSTRACT: The heating rate used during semen thawing plays an important role in reducing structural and functional damage to spermatozoa. In this study, we evaluated the influence of thawing temperature on semen quality, reactive oxygen species (ROS) production, and mitochondrial activity of cryopreserved bovine semen. A total of 195 straws of 0.5 mL from five Holstein Friesian bulls were used (39 straws per bull). Samples underwent 8 to 22 years of storage; they were processed under a standard protocol with tris-egg yolk and stored in liquid nitrogen. Samples were thawed for 30 seconds in a water bath at T1: 36 °C, T2: 38 °C or T3: 40 °C. Sperm motility and kinematics, morphology, structural membrane integrity (SMI), functional membrane integrity (FMI), acrosome integrity (AI), ROS, and mitochondrial membrane potential (ΔΨM) of post-thawing bovine sperm were evaluated. Generalized linear models were fitted to the data. Each model included the effects of bull, storage time, and treatment. The Shapiro-Wilk test was used to assess data normality, and means were compared using the Tukey test. T2 and T3 showed better results for sperm motility and kinematic parameters, SMI (%) (T1 41.9 ± 2.3; T2 45.7 ± 1.9; T3 47.4 ± 2.8), ROS (RFU/min) (T1 0.026 ± 0.007; T2 0.032 ± 0.001; T3 0.031 ± 0.001) and high-ΔΨM (RFU x 103) (67.1± 0,4; 71.3 ± 0.4; 74.2 ± 0.4) (P < 0.05). However, T1 had higher FMI (39.3 ± 2.3) than T2 (34.0 ± 1.9) (P < 0.05), though not significantly (P > 0.05) different from T3 (38.4 ± 2.2). Thawing temperatures of 38 °C and 40 °C increases motility, kinetics, membrane integrity, mitochondrial activity and ROS of cryopreserved bovine semen, compared with more conventional thawing at 36 °C.

RESUMO: A taxa de aquecimento usada durante o descongelamento do sêmen desempenha um papel importante na redução dos danos estruturais e funcionais nos espermatozóides. O objetivo desta pesquisa foi avaliar a influência da temperatura de descongelamento na qualidade do sêmen, produção de espécies reativas de oxigênio (ROS) e atividade mitocondrial do sêmen bovino criopreservado. Foram utilizados 195 palhetas de 0,5 mL de cinco touros Holstein Friesian (39 palhetas por touro). As amostras passaram por oito a 22 anos de armazenamento e foram processadas sob protocolo padrão com Tris-gema de ovo e armazenadas em nitrogênio líquido. As temperaturas de descongelamento foram T1: 36 °C, T2: 38 °C, T3: 40 °C, cada uma por 30 segundos em banho-maria. Pós-descongelamento, a motilidade e cinética dos espermatozoides, morfologia, integridade estrutural da membrana (SMI), integridade funcional da membrana (FMI), integridade acrossomal (AI), ROS e potencial de membrana mitocondrial (ΔΨM) foram avaliados. Modelos lineares generalizados foram ajustados. Cada modelo incluiu os efeitos de touro, tempo de armazenamento e tratamento. A normalidade dos dados foi avaliada pelo teste de Shapiro-Wilk e as médias comparadas pelo teste de Tukey. T2 e T3 apresentaram resultados mais elevados para a maioria dos parâmetros de motilidade e cinemática espermática, SMI (%) (T1 41,9 ± 2,3; T2 45,7 ± 1,9; T3 47,4 ± 2,8), ROS (RFU/min) (T1 0,026 ± 0,007; T2 0,032 ± 0,001; T3 0,031 ± 0,001) e alto ΔΨM (RFU x 103) (67,1 ± 0,4; 71,3 ± 0,4; 74,2 ± 0,4) (P < 0,05). No entanto, T1 apresentou maior FMI (%) (39,3 ± 2,3) em comparação a T2 (34,0 ± 1,9) (P < 0,05), mas não foi diferente do T3 (38,4 ± 2,2) (P > 0,05). Conclui-se que as temperaturas de descongelamento de 38 °C e 40 °C produzem um aumento na motilidade, cinética, integridade de membrana, atividade mitocondrial e ROS do sêmen bovino criopreservado, em comparação com o uso mais convencional de uma temperatura de descongelamento de 36 °C.

Resumo

The objective of this study was to reduce the effects of cryoinjury caused in bovine semen by cryopreservation. Ejaculates were collected from Nellore bulls and subjected to freezing in C (control), ozone (15, 30, and 60 µg mL-1 of ozone), quercetin (25, 50, and 100 µg mL-1 of quercetin), and carnosine groups (100, 200, and 300 ng mL-1 of carnosine). Samples were evaluated post-thaw (M0) and post-rapid thermoresistance test (M30) for sperm kinetics (total motility, progressive motility, curvilinear speed, linearity and amplitude of lateral head displacement) and cell structure viability (plasma membrane integrity, acrosomal integrity, mitochondrial potential, membrane fluidity, and lipid peroxidation). There were no differences (P > 0.05) between the control, quercetin, and carnosine-treated groups for the parameters evaluated at M0 and M30. In turn, supplementation with ozone resulted in lower values for sperm kinetics (P < 0.05) and lower mitochondrial potential at M30 (P < 0.05). Quercetin and carnosine at the concentrations used did not promote significant gains in frozen semen, nor did they demonstrate cytotoxicity. We expected to obtain positive results with the use of ozone. Nonetheless, the addition was harmful to the parameters of sperm kinetics, and its effect was not observed as a possible pro-antioxidant. We believe that the fact that the gas did not harm the sperm structure opens avenues for tests with lower dosages, since, by reducing its concentration, we could minimize the damage to sperm kinetics.(AU0

Resumo

The heating rate used during semen thawing plays an important role in reducing structural and functional damage to spermatozoa. In this study, we evaluated the influence of thawing temperature on semen quality, reactive oxygen species (ROS) production, and mitochondrial activity of cryopreserved bovine semen. A total of 195 straws of 0.5 mL from five Holstein Friesian bulls were used (39 straws per bull). Samples underwent 8 to 22 years of storage; they were processed under a standard protocol with tris-egg yolk and stored in liquid nitrogen. Samples were thawed for 30 seconds in a water bath at T1: 36 °C, T2: 38 °C or T3: 40 °C. Sperm motility and kinematics, morphology, structural membrane integrity (SMI), functional membrane integrity (FMI), acrosome integrity (AI), ROS, and mitochondrial membrane potential (ΔΨM) of post-thawing bovine sperm were evaluated. Generalized linear models were fitted to the data. Each model included the effects of bull, storage time, and treatment. The Shapiro-Wilk test was used to assess data normality, and means were compared using the Tukey test. T2 and T3 showed better results for sperm motility and kinematic parameters, SMI (%) (T1 41.9 ± 2.3; T2 45.7 ± 1.9; T3 47.4 ± 2.8), ROS (RFU/min) (T1 0.026 ± 0.007; T2 0.032 ± 0.001; T3 0.031 ± 0.001) and high-ΔΨM (RFU x 103) (67.1± 0,4; 71.3 ± 0.4; 74.2 ± 0.4) (P < 0.05). However, T1 had higher FMI (39.3 ± 2.3) than T2 (34.0 ± 1.9) (P < 0.05), though not significantly (P > 0.05) different from T3 (38.4 ± 2.2). Thawing temperatures of 38 °C and 40 °C increases motility, kinetics, membrane integrity, mitochondrial activity and ROS of cryopreserved bovine semen, compared with more conventional thawing at 36 °C.

A taxa de aquecimento usada durante o descongelamento do sêmen desempenha um papel importante na redução dos danos estruturais e funcionais nos espermatozóides. O objetivo desta pesquisa foi avaliar a influência da temperatura de descongelamento na qualidade do sêmen, produção de espécies reativas de oxigênio (ROS) e atividade mitocondrial do sêmen bovino criopreservado. Foram utilizados 195 palhetas de 0,5 mL de cinco touros Holstein Friesian (39 palhetas por touro). As amostras passaram por oito a 22 anos de armazenamento e foram processadas sob protocolo padrão com Tris-gema de ovo e armazenadas em nitrogênio líquido. As temperaturas de descongelamento foram T1: 36 °C, T2: 38 °C, T3: 40 °C, cada uma por 30 segundos em banho-maria. Pós-descongelamento, a motilidade e cinética dos espermatozoides, morfologia, integridade estrutural da membrana (SMI), integridade funcional da membrana (FMI), integridade acrossomal (AI), ROS e potencial de membrana mitocondrial (ΔΨM) foram avaliados. Modelos lineares generalizados foram ajustados. Cada modelo incluiu os efeitos de touro, tempo de armazenamento e tratamento. A normalidade dos dados foi avaliada pelo teste de Shapiro-Wilk e as médias comparadas pelo teste de Tukey. T2 e T3 apresentaram resultados mais elevados para a maioria dos parâmetros de motilidade e cinemática espermática, SMI (%) (T1 41,9 ± 2,3; T2 45,7 ± 1,9; T3 47,4 ± 2,8), ROS (RFU/min) (T1 0,026 ± 0,007; T2 0,032 ± 0,001; T3 0,031 ± 0,001) e alto ΔΨM (RFU x 103) (67,1 ± 0,4; 71,3 ± 0,4; 74,2 ± 0,4) (P < 0,05). No entanto, T1 apresentou maior FMI (%) (39,3 ± 2,3) em comparação a T2 (34,0 ± 1,9) (P < 0,05), mas não foi diferente do T3 (38,4 ± 2,2) (P > 0,05). Conclui-se que as temperaturas de descongelamento de 38 °C e 40 °C produzem um aumento na motilidade, cinética, integridade de membrana, atividade mitocondrial e ROS do sêmen bovino criopreservado, em comparação com o uso mais convencional de uma temperatura de descongelamento de 36 °C.

Resumo

The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.

O armazenamento a frio de leite implica potenciais alterações em sua qualidade, pois gera como processo principal radicais livres que provocam danos aos lipídios da membrana dos espermatozoides, com as consequentes alterações na motilidade e na capacidade de fertilização. Para diminuir os danos causados pelos radicais livres, as células têm defesas antioxidantes (proteínas, enzimas e substâncias de baixo peso molecular). O presente estudo avaliou o efeito do tempo de armazenamento e diferentes antioxidantes preparados em diluentes espermáticos no armazenamento de viabilidade de O. mykiss milt a 4°C. A ANOVA de duas vias denotou que o armazenamento no tempo e a influência antioxidante têm efeitos significativos separados ou combinados nos parâmetros de viabilidade (motilidade espermática, viabilidade espermática, concentrações de proteínas e atividade enzimática da superóxido dismutase no plasma seminal), enquanto apenas o tempo de armazenamento afetou a capacidade de fertilização e atividade enzimática da catalase no plasma seminal. A análise resultante pode concluir que a presença de antioxidante melhora a viabilidade do leite frio, especialmente as condições de transporte, e os antioxidantes permitem a fecundidade apesar da diminuição da motilidade.

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Letrozole comprises a non-steroid aromatase inhibitor that has been applied as a preventive for many uses, such as breast cancer prevention, treatment of hormonal dysfunction, and male infertility. Precisely in Northeast Brazil, ovine consist of the leading livestock produced, and their reproduction in captivity has been demonstrated difficult. Thus, we hypothesized whether the application of letrozole will improve male sheep reproduction. One group of 6 animals received a daily dosage of 0.5mg/Kg of letrozole for 60 days, while the other six animals were used as control. Samples were collected from control and treated animals after 30 and 60 days of the experiment. Blood samples were collected to measure the steroid hormone levels. Semen was collected from control and treated groups using an artificial vagina and cryopreserved for spermatozoa morphology and CASA analysis. The testicles were collected for histological analysis, gene expression, and immunohistochemistry of P450aromatase protein. Hormone levels demonstrate no differences in the estradiol/testosterone levels among the control and both treated groups. Immunohistochemistry analysis revealed the presence of P450aromatase protein in spermatogonia cells and Leydig cells in the control and treated groups in both periods analyzed. Moreover, there were no differences in the P450aromase gene expression in the control and treated group. Morphological analysis of the spermatozoa revealed that letrozole treatment did not affect mitochondrial activity or cause any deformities. In addition, motility parameters in the sperm from the treated group were not affected by letrozole treatment compared to the control group. Morphological analysis of the testis demonstrated that letrozole treatment increase the seminiferous tubule area but no signs of germ cell damage. Our results show that letrozole has a morphological effect on the testicles in the ovine model but no pathological or severe effect caused by hormone level imbalance. Overall, letrozole comprises a non-steroid aromatase inhibitor, which can be applied to ovine reproduction.(AU)

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As perdas de produtividade e fertilidade animal associadas ao estresse térmico durante os meses mais quentes do ano é um dos maiores desafios do setor pecuário. Na indústria de leite as perdas econômicas causadas pelo estresse térmico foram estimadas em mais de 1,5 bilhões de dólares por ano. No que tange a reprodução, já foi demonstrado que o estresse térmico exerce múltiplos efeitos deletérios, causando disfunções endócrinas e alterando a sequência orquestrada de eventos importantes para a gametogênese e para o desenvolvimento embrionário inicial. Estudos recentes têm esclarecido o padrão temporal no qual os danos são estabelecidos e carreados dependendo da intensidade do estresse. Enquanto os efeitos imediatos do estresse térmico nos gametas já são bem caracterizados, existem evidências de que alguns danos podem ser carreados de forma tardia e possivelmente entre gerações. Além disso, dados emergentes indicam que o estresse térmico compromete a reprogramação da metilação do DNA que ocorre durante a gametogênese e a programação do desenvolvimento in utero. Dessa forma, esse artigo visa explorar os efeitos imediatos, tardios e transgeracionais do estresse térmico nos gametas.(AU)

The drop on animal productivity and fertility associated with heat stress during the hot months of the year is one of the biggest challenges for the livestock sector. For the dairy industry the economic losses caused by heat stress have been estimated over 1.5 billion dollars per year. It has already been demonstrated that heat stress exerts multiple deleterious effects on reproductive function, causing endocrine dysfunctions as well as changes in the sequence of events required for gametogenesis and early embryonic development. Recent studies have shed a light in the temporal pattern in which heat-induced damage is established and carried forward depending on the intensity of stress. While the immediate effects of heat stress on gametes are well characterized, there is evidence that some damage can be carried over for longer periods and even across generations. Furthermore, emerging data indicate that heat stress compromises DNA methylation reprogramming that occurs during gametogenesis and developmental programming in utero. Thus, this paper aims to explore the immediate, late and transgenerational effects of heat stress on gametes.(AU)

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Cadmium (Cd) is one of the major toxicants, which affects human health through occupational and environmental exposure. In the current study, we evaluated the protective effects of morel mushrooms against Cd-induced reproductive damages in rats. For this purpose, 30 male rats were divided into 6 groups (n=5/group), the first group served as the control group, second group was treated with an intraperitoneal (i.p) injection of 1 mg/kg/day of Cd. Third and fourth groups were co-treated with 1 mg/kg/day of Cd (i.p) and 10 and 20 mg/kg/day of morel mushroom extract (orally) respectively. The final 2 groups received oral gavage of 10 and 20 mg/kg/day of morel mushroom extract alone. After treatment for 17 days, the animals were euthanized, and testes and epididymis were dissected out. One testis and epididymis of each animal were processed for histology, while the other testis and epididymis were used for daily sperm production (DSP) and comet assay. Our results showed that Cd and morel mushrooms have no effect on animal weight, but Cd significantly decreases the DSP count and damages the heritable DNA which is reversed in co-treatment groups. Similarly, the histopathological results of tests and epididymis show that morel mushrooms control the damage to these tissues. Whereas the morel mushroom extract alone could enhance the production of testosterone. These results conclude that morel mushrooms not only control the damage done by Cd, but it could also be used as a protection mechanism for heritable DNA damage.

O cádmio (Cd) é um dos principais tóxicos, que afeta a saúde humana por meio da exposição ocupacional e ambiental. No presente estudo, avaliamos os efeitos protetores dos cogumelos morel contra os danos reprodutivos induzidos pelo Cd em ratos. Para tanto, 30 ratos machos foram divididos em 6 grupos (n = 5 / grupo); o primeiro grupo serviu de controle, o segundo grupo foi tratado com injeção intraperitoneal (i.p) de 1 mg / kg / dia de Cd. O terceiro e o quarto grupos foram cotratados com 1 mg / kg / dia de Cd (i.p) e 10 e 20 mg / kg / dia de extrato de cogumelo morel (por via oral), respectivamente. Os dois grupos finais receberam gavagem oral de 10 e 20 mg / kg / dia de extrato de cogumelo morel sozinho. Após o tratamento por 17 dias, os animais foram sacrificados e os testículos e o epidídimo foram dissecados. Um testículo e epidídimo de cada animal foram processados para histologia, enquanto o outro testículo e epidídimo foram usados para produção diária de esperma (DSP) e ensaio cometa. Nossos resultados mostraram que os cogumelos Cd e morel não têm efeito sobre o peso do animal, mas o Cd diminui significativamente a contagem de DSP e danifica o DNA hereditário, que é revertido em grupos de cotratamento. Da mesma forma, os resultados histopatológicos dos testículos e do epidídimo mostram que os cogumelos morel controlam os danos a esses tecidos. Considerando que o extrato de cogumelo morel sozinho pode aumentar a produção de testosterona. Esses resultados concluem que os cogumelos morel não apenas controlam os danos causados pelo Cd, mas também podem ser usados como um mecanismo de proteção para danos hereditários ao DNA.

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Although cryopreservation is an efficient method for maintaining the biological and genetic resources of sperm, the sperm damage during the cryopreservation process cannot be ignored. It should be possible to obtain the most effective cryopreservation performance by accurately grasping the effects of various factors on the cryopreservation of sperm. The previous study demonstrated that a suitable standard protocol for cryopreservation of Korean native brindled cattle (Chikso) does not exist, based on the methods for semen cryopreservation of Chikso differ in each research center. The most obvious difference between most of protocols is the addition of glycerol before and after cooling during the Chikso cryopreserved semen process. Therefore we focused on the effects of glycerol addition time on the quality of cryopreserved Chikso sperm. In the present study, 27 individual Chikso samples were collected by transrectal massage and divided into two parts: the "cryopreservation method A" group (adding glycerol before cooling) and the "cryopreservation method B" group (adding glycerol after cooling). Meanwhile, the values of various sperm parameters were derived from each group, including sperm motility, kinematics, capacitation status, cell viability, and intracellular ATP levels, which we used to compare and evaluate sperm function. The results of this study indicated that during the semen cryopreservation process of the Chikso, the addition of glycerol after cooling yielded superior results in a variety of sperm parameters, such as sperm motility, progressive motility, rapid motility, VCL, VSL, VAP, ALH, capacitation status, viability, and intracellular ATP level after freezing and thawing. Our study is suggested that the glycerol addition time during the cryopreservation process for Chikso should be considered. In addition, our results may be provided reference to develop suitable the cryopreservation procedure of the Chikso sperm.(AU)

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Background: The use of conventional artificial insemination (AI) in sheep production is usually associated with lower fertility rates when frozen semen is used. Cooled ram semen has been an alternative over frozen semen due to the higher viability, seminal quality and fertility rates following AI. The semen preservation process promotes sperm cell modifications similar to capacitation (capacitation-like) that causes cell damage affecting viability and seminal quality, but such effects are unclear for cooled semen. The aim of this study was to determine the status of sperm cell capacitation (CA) and acrosome reaction (AR) during ram semen processing and cooling under different extenders, dilution factors, and aerobiosis conditions as a function of storage time at 5o C. Materials, Methods & Results: Two consecutive ejaculates per day per male were collected from 2 adult rams by artificial vagina at 48-72 h intervals, in three replications. After macro- and microscopic evaluations, semen was segregated into groups under 3 extenders (Tris-egg yolk or TY, citrate-egg yolk or CY, skimmed milk or SM), 2 dilution factors (1 x 109 or Bi, 100 x 106 or Mi cells/mL), and 2 aerobiosis conditions (aerobic or A, semi-anaerobic or SA). Diluted semen was cooled to 5ºC and stored for up to 72 h, with evaluations every 24 h. Aliquots of fresh ejaculates and of each cooled diluted subgroup, according to extender, dilution, and aerobiosis, were collected at times T0 and T72 for determination of acrosome status and membrane integrity by the chlortetracycline (CTC) and trypan blue-Giemsa stainings, respectively. No differences were detected in sperm cell motility (M) and motility vigor (V) between fresh and diluted semen. After cooling, a significant decrease in M was observed after 48 h in CY and SM compared with fresh semen and 0 h of cooling, while V started to decrease after 24 h in CY compared with TY. Likewise, M/V from different dilutions and aerobic conditions decreased more significantly after 48 and 24 h of cooling, respectively. The sperm capacitation status did not show differences in the proportion of non-capacitated (NCA), CA and AR sperm cells between TY, CY, and SM extenders (NCA: 75.0%, 71.3%, 74.0%; CA: 15.7%, 17.2%, 15.9%; AR: 9.3%, 11.5%, 10.2%) or between Bi and Mi dilutions (NCA: 74.0%, 72.9%; CA: 15.9%, 16.6%; AR: 10.1%, 10.5%), respectively. However, differences (P < 0.05) were observed between A and SA aerobic conditions, with CA (17.0% vs. 15.5%) and AR (11.9% vs. 8.7%) rates being higher in A than SA, respectively, with no differences in NCA (71.1% vs. 75.8%), irrespective of the storage time. Sperm cell viability decreased after 48 h, especially in CY (P < 0.05). Discussion: Ram sperm cells can suffer irreversible damage due to thermal shock during cooling. Egg yolk-based extenders provide phospholipids and cholesterol to protect the sperm cell membrane during the thermal shock caused by the change in temperature. In this study, sperm cells had irreversible decreases in M/V, with increase in acrosome and plasma membrane damage after cooling to 5ºC. The largest and smallest decreases in M and V over time were observed in the CY and TY extenders, respectively. In addition to the extender type, the semen preservation method and storage time promoted changes in the capacitation status, AR and in sperm cell viability, which per se were associated with a decrease in semen fertility. In fact, the proportions of CA and/or AR sperm cells gradually increased over time after dilution and storage at 5ºC, with a negative correlation between sperm cell viability and M/V over time. In summary, extender and cooling time affected mostly M/V, while aerobiosis condition and dilution factor were more associated with acrosome status and sperm survival, with the extender having less impact on the acrosome status as a function of time.

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The present study investigated the toxic effect of a mixture of three pesticides (cypermethrin, mancozeb, and metalaxyl) on reproduction and oxidative stress parameters in male Wistar rats. Animals were treated at doses 1/60, 1/30, and 1/10 LD50 of each pesticide daily in the diet for 08 weeks. At the end of the treatment period, animals were sacrificed by decapitation. The results indicate a decrease in the absolute weight of testes and epididymis, the serum of testosterone hormone, and cholesterol levels. These parameters were significant reduced in males exposed to the mixed pesticides. A reduction in sperm concentration, motility, and viability also was observed. Besides, the ingestion of mixed pesticides at all three concentrations caused a significant decrease in GSH, GPx levels and an increase in MDA levels compared to the control group. This was accompanied by histopathological changes in testis and epididymis of rats such as seminiferous tubules degeneration, decreasing number of spermatogenic cells, edema, expansion of interstitial spaces, cell necrosis, and reducing the diameter of the epididymal tube compared to the control group. Thus, we strongly suggest that the mixture of pesticides causes damages to the male reproductive system.(AU)

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Purpose: Myocardial ischemia/reperfusion (MI/R) injury refers to a pathological condition of treatment of myocardial infarction. Oxidative stress and inflammation are believed to be important mechanisms mediating MI/R injury. Kukoamine A (KuA), a sperm, is the main bioactive component extracted from the bark of goji berries. In this study, we wanted to investigate the possible effects of KuA on MI/R injury. Methods: In this experiment, all rats were divided into sham operation group, MI/R group, KuA 10 mg + MI/R group, KuA 20 mg + MI/R group. After 120 min of ischemia/reperfusion treatment, left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), maximal rates of rising and fall of left ventricular pressure (±dp/dtmax), and ischemic area were detected. Serum samples of rats in each group were collected. The enzyme activities of catalase (CAT), glutathione peroxidase (GSH-PX), superoxide dismutase (SOD), levels of malondialdehyde (MDA), CK muscle/brain (CK-MB), tumor necrosis factor (TNF), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) were detected using enzyme-linked immunosorbent assay (ELISA). The apoptosis of myocardium in each group was detected according to the instructions of the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The expressions of mammalian target of glycogen synthase kinase-3ß (GSH-3ß) and protein kinase B (Akt) mRNA level in myocardial tissues were detected via reverse transcription-polymerase chain reaction (RT-PCR). Results: MI/R rats showed a significant increase in oxidative stress and inflammation. In addition, we showed that KuA significantly improved the myocardial function such as LVSP, left ventricular ejection fraction, +dp/dt, and -dp/dt. Here, it attenuated dose-dependent histological damage in ischemia-reperfused myocardium, which is associated with the enzyme activities of SOD, GSH-PX, and levels of MDA, IL-6, TNF-α, L-1ß. Conclusions: KuA inhibited gene expression of Akt/GSK-3ß, inflammation, oxidative stress and improved MR/I injury. Taken together, our results allowed us to better understand the pharmacological activity of KuA against MR/I injury.

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Antioxidants are natural or synthetic substances that delay oxidation through one or more mechanisms, such as scavenging free radicals, inhibiting lipid peroxidation, and complexing with metals, inhibiting tissue destruction via oxidation. Antioxidants are commonly used in animal feed and the food industry to prevent the oxidation of animal-origin products. Moreover, natural oxidants are used increasingly in animal reproduction, especially for semen preservation. In this context, this study aimed to review the applications of natural antioxidants in animal reproduction. We observed that the bulk of the natural antioxidants, approximately 80.4%, were commercially acquired and used mainly for semen cooling/freezing (72%) with promising results (90%) in Sus scrofa (boar), Capra aegagrus hircus (goat), Gallus gallus domesticus (rooster), and Ovis aries (ram). However, further studies are needed to help determine the appropriate dosage of natural antioxidants for applications.

Antioxidantes são substâncias naturais ou sintéticas que facilitam o retardo da oxidação por um ou mais mecanismos, como sequestrar radicais livres, inibir a peroxidação lipídica e complexar com metais, inibindo a destruição tecidual via oxidação. Antioxidantes são comumente usados na alimentação animal e na indústria alimentícia para prevenir a oxidação de produtos de origem animal. Além disso, os oxidantes naturais estão sendo cada vez mais aplicados na reprodução animal, principalmente na preservação do sêmen. Nesse contexto, este trabalho teve como objetivo revisar a aplicação de antioxidantes naturais na reprodução animal. Observamos que os antioxidantes naturais foram geralmente adquiridos comercialmente (80,4%) e utilizados principalmente no resfriamento/congelamento de sêmen (72%) com resultados promissores (90%) em Sus scrofa (javali), Capra aegagrus hircus (cabra), Gallus gallus domesticus (galo) e Ovis aries (carneiro). No entanto, mais estudos devem ser realizados para ajudar a regular a dosagem de antioxidantes naturais para sua aplicação.