Plasma seminal ovino e sua aplicação na biotecnologia reprodutiva / Ram seminal plasma and use in reproductive biotechnology

O plasma seminal de ovinos tem importante atuação na função espermática e na fertilização. Em ovinos, a adição do plasma seminal ou de suas proteínas tem apresentado resultados favoráveis na qualidade do sêmen ovino criopreservado. Entretanto, resultados divergentes têm sido obtidos, possivelmente relacionados à variação da composição do plasma seminal. Compreender a função e os mecanismos que envolvem a interação plasma seminal-espermatozoide poderia ajudar na formulação de diluidores seminais e aperfeiçoar protocolos de criopreservação. (AU)

The ram seminal plasma plays a important role in sperm function and fertilization. The addition of seminal plasma or its proteins has presented favorable results in cryopreserved ram semen quality. However, divergent result has been obtained, possibly related to variation in the composition of seminal plasma. Understand the role and mechanisms involved in sperm-seminal plasma interaction could help to formulating seminal extenders and improve cryopreservation protocols.(AU)

Plasma seminal ovino e sua aplicação na biotecnologia reprodutiva / Ram seminal plasma and use in reproductive biotechnology

O plasma seminal de ovinos tem importante atuação na função espermática e na fertilização. Em ovinos, a adição do plasma seminal ou de suas proteínas tem apresentado resultados favoráveis na qualidade do sêmen ovino criopreservado. Entretanto, resultados divergentes têm sido obtidos, possivelmente relacionados à variação da composição do plasma seminal. Compreender a função e os mecanismos que envolvem a interação plasma seminal-espermatozoide poderia ajudar na formulação de diluidores seminais e aperfeiçoar protocolos de criopreservação.

The ram seminal plasma plays a important role in sperm function and fertilization. The addition of seminal plasma or its proteins has presented favorable results in cryopreserved ram semen quality. However, divergent result has been obtained, possibly related to variation in the composition of seminal plasma. Understand the role and mechanisms involved in sperm-seminal plasma interaction could help to formulating seminal extenders and improve cryopreservation protocols.

Fertility-associated proteins in male and female reproductive fluids of cattle

This paper outlines a 25 yr research strategy to better understand how proteins in male and female reproductive fluids influence fertility. Extensive fertility data available from artificial insemination cooperatives were used to identify individual dairy bulls with phenotypes of above and below average fertility. We determined whether the protein composition of reproductive fluids from these bulls differed with fertility. Surgical alteration of bulls to equip them with indwelling vas deferens cannulae enabled recovery of accessory sex gland fluid an d cauda epididymal fluid and sperm for in vitro studies. Extensive analyses of reproductive fluids from these unique individuals enabled identification of several proteins that were associated with fertility. Methods to cannulate the oviducts of cows were also used to evaluate the composition and function of oviductal fluid. In vitro testing of proteins purified from male and female reproductive fluids demonstrated that they facilitated sperm capacitation, fertilization and early embryo development. Collectively these studies pursued a reductionist approach that st arted with the phenotype of an animal, use of surgical techniques to acquire reproductive fluids, use of analytical tools to define the composition and their relationships to fertility, and ultimately the purified proteins were tested with gametes and embryos to assess function. Using this approach, hypotheses were te sted to determine fertility- related functions of proteins in reproductive fluids. The results provide an understanding of how fertility-related proteins contribute to the fertility phenotype of an individual and provide insights into potential applications to improve the fertility of cattle.(AU)

Gema do ovo de galinha e a ação protetora de suas lipoproteínas de baixa densidade na criopreservação do sêmen: uma revisão / Hens egg yolk and the protective action of its low density lipoproteins on semen cryopreservation: a review

Desde 1939, a gema do ovo tem sido utilizada na biotecnologia da reprodução como ingrediente essencial nos meios diluidores para resfriamento e congelamento de espermatozoides em várias espécies domésticas. A gema é formada por lipoproteínas, livetinas e fosvitinas, encontradas em duas frações facilmente separáveis pelo método de centrifugação: o grânulo e o plasma. Acredita-se que as lipoproteínas de baixa densidade, presentes no plasma, sejam as responsáveis por sua ação crioprotetora. Esta revisão enfoca a composição química do ovo de galinha e de sua gema, mostrando, cronologicamente, como foram desenvolvidas as hipóteses existentes sobre seu mecanismo de ação no congelamento de sêmen.(AU)

Since 1939, the hens egg yolk has been used as an essential ingredient in extenders for cooling and freezing sperm of several domestic species, in reproductive biotechnology protocols. The egg yolk is composed of lipoproteins, livetins, and lipovitins. These components can be easily separated by centrifugation in the granular and the plasmatic fractions. It has been acknowledged that the low density lipoproteins present in the plasma are responsible for the protective effects of the egg yolk. This review focuses on the chemical compound of the egg yolk and historical aspects of the hypotheses that try to explain the mechanism of action of the egg yolk on sperm cryopreservation. (AU)

Fertility-associated proteins in male and female reproductive fluids of cattle

This paper outlines a 25 yr research strategy to better understand how proteins in male and female reproductive fluids influence fertility. Extensive fertility data available from artificial insemination cooperatives were used to identify individual dairy bulls with phenotypes of above and below average fertility. We determined whether the protein composition of reproductive fluids from these bulls differed with fertility. Surgical alteration of bulls to equip them with indwelling vas deferens cannulae enabled recovery of accessory sex gland fluid an d cauda epididymal fluid and sperm for in vitro studies. Extensive analyses of reproductive fluids from these unique individuals enabled identification of several proteins that were associated with fertility. Methods to cannulate the oviducts of cows were also used to evaluate the composition and function of oviductal fluid. In vitro testing of proteins purified from male and female reproductive fluids demonstrated that they facilitated sperm capacitation, fertilization and early embryo development. Collectively these studies pursued a reductionist approach that st arted with the phenotype of an animal, use of surgical techniques to acquire reproductive fluids, use of analytical tools to define the composition and their relationships to fertility, and ultimately the purified proteins were tested with gametes and embryos to assess function. Using this approach, hypotheses were te sted to determine fertility- related functions of proteins in reproductive fluids. The results provide an understanding of how fertility-related proteins contribute to the fertility phenotype of an individual and provide insights into potential applications to improve the fertility of cattle.

Gema do ovo de galinha e a ação protetora de suas lipoproteínas de baixa densidade na criopreservação do sêmen: uma revisão / Hen’s egg yolk and the protective action of its low density lipoproteins on semen cryopreservation: a review

Desde 1939, a gema do ovo tem sido utilizada na biotecnologia da reprodução como ingrediente essencial nos meios diluidores para resfriamento e congelamento de espermatozoides em várias espécies domésticas. A gema é formada por lipoproteínas, livetinas e fosvitinas, encontradas em duas frações facilmente separáveis pelo método de centrifugação: o grânulo e o plasma. Acredita-se que as lipoproteínas de baixa densidade, presentes no plasma, sejam as responsáveis por sua ação crioprotetora. Esta revisão enfoca a composição química do ovo de galinha e de sua gema, mostrando, cronologicamente, como foram desenvolvidas as hipóteses existentes sobre seu mecanismo de ação no congelamento de sêmen.

Since 1939, the hen’s egg yolk has been used as an essential ingredient in extenders for cooling and freezing sperm of several domestic species, in reproductive biotechnology protocols. The egg yolk is composed of lipoproteins, livetins, and lipovitins. These components can be easily separated by centrifugation in the granular and the plasmatic fractions. It has been acknowledged that the low density lipoproteins present in the plasma are responsible for the protective effects of the egg yolk. This review focuses on the chemical compound of the egg yolk and historical aspects of the hypotheses that try to explain the mechanism of action of the egg yolk on sperm cryopreservation.

Proteínas do plasma seminal, funções espermáticas e marcadores moleculares da fertilidade / Seminal plasma proteins, sperm functions and molecular markers of fertility

Componentes moleculares dos espermatozoides, ou dos meios que os cercam, influenciam a capacidade fecundante destas células. Dado tal conceito, proteínas do plasma seminal modulam cruciais funções e processos da reprodução, como a motilidade e capacitação espermática, proteção celular, reação acrossômica e fertilização. As relações empíricas entre índices de fertilidade e proteínas seminais em determinadas espécies indicam que estas proteínas têm o potencial de serem identificadas como marcadores da capacidade reprodutiva do macho.(AU)

Molecular components of the sperm, or from the media that surround them, influence the fertilizing capacity of such cells. Given this concept, proteins of the seminal plasma modulate crucial functions and events of reproduction, such as sperm motility and capacitation, cell protection, acrosome reaction and fertilization. Empirical associations between some proteins and fertility indexes in certain species indicate that these proteins can be potentially identified as molecular markers of the male reproductive status.(AU)

Proteínas do plasma seminal, funções espermáticas e marcadores moleculares da fertilidade / Seminal plasma proteins, sperm functions and molecular markers of fertility

Componentes moleculares dos espermatozoides, ou dos meios que os cercam, influenciam a capacidade fecundante destas células. Dado tal conceito, proteínas do plasma seminal modulam cruciais funções e processos da reprodução, como a motilidade e capacitação espermática, proteção celular, reação acrossômica e fertilização. As relações empíricas entre índices de fertilidade e proteínas seminais em determinadas espécies indicam que estas proteínas têm o potencial de serem identificadas como marcadores da capacidade reprodutiva do macho.

Molecular components of the sperm, or from the media that surround them, influence the fertilizing capacity of such cells. Given this concept, proteins of the seminal plasma modulate crucial functions and events of reproduction, such as sperm motility and capacitation, cell protection, acrosome reaction and fertilization. Empirical associations between some proteins and fertility indexes in certain species indicate that these proteins can be potentially identified as molecular markers of the male reproductive status.