Association between the presence of a 38 kDa factor in the seminal plasma and inhibition of sperm motility in jundiá fish Rhamdia quelen / Associação entre a presença de um fator de 38 kDa no plasma seminal e a inibição da motilidade espermática no jundiá Rhamdia quelen

Fatores proteicos tem sido indentificados no plasma seminal de peixes e mamíferos e, em algumas situações, associados com indicadores de qualidade espermática. Entretanto, para o jundiá (Rhamdia quelen), tais fatores como aqueles com potenciais associações ainda não foram descritos. Os objetivos deste estudo foram de identificar alguns fatores proteicos presentes no plasma seminal do jundiá e avaliar suas associações com a motilidade espermática. Através de eletroforese do tipo SDS-PAGE foram identificadas 14 bandas proteicas com peso molecular entre 217.1 e 7.1 kDa. A motilidade espermática foi avaliada em 21 machos. Quatro bandas proteicas (81.5; 60.4; 33.6 e 25.5 kDa) foram detectadas em todas as amostras de plasma seminal analisadas. Uma banda proteica com peso molecular de 38.3 kDa foi associada com a baixa motilidade espermática no jundiá (P< 0,01), uma vez que foi detectada em 91.4% das amostras com motilidade menor que 80%. Estes resultados sugerem que esta banda proteica seminal associada com a baixa motilidade espermática poderá ser considerada como um potencial marcador bioquímico de qualidade seminal.(AU)

Protein factors have been identified in the seminal plasma of fish and mammal species and, in some situations, associated to sperm quality indicators. However, for jundiá fish (Rhamdia quelen), such factors and those potential associations remain unknown. In the present study, we aimed to identify some protein factors present in the seminal plasma of jundiá fish and to evaluate their association to sperm motility. SDS-PAGE was used to identify 14 bands, with molecular weight ranging from 217.1 to 7.1 kDa. Sperm motility was evaluated for 21 males. Four protein bands (81.5; 60.4; 33.6; and 25.5 kDa) were present in all seminal plasma samples. One protein band with molecular weight of 38.3 kDa was associated to reduced sperm motility of jundiá (P<0.01), since it was detected in 91.4% of the samples having motility lower than 80%. These results suggest that this seminal protein band associated to lower sperm motility may be considered a potential biochemical marker for sperm quality.(AU)

Association between the presence of a 38 kDa factor in the seminal plasma and inhibition of sperm motility in jundiá fish Rhamdia quelen / Associação entre a presença de um fator de 38 kDa no plasma seminal e a inibição da motilidade espermática no jundiá Rhamdia quelen

Fatores proteicos tem sido indentificados no plasma seminal de peixes e mamíferos e, em algumas situações, associados com indicadores de qualidade espermática. Entretanto, para o jundiá (Rhamdia quelen), tais fatores como aqueles com potenciais associações ainda não foram descritos. Os objetivos deste estudo foram de identificar alguns fatores proteicos presentes no plasma seminal do jundiá e avaliar suas associações com a motilidade espermática. Através de eletroforese do tipo SDS-PAGE foram identificadas 14 bandas proteicas com peso molecular entre 217.1 e 7.1 kDa. A motilidade espermática foi avaliada em 21 machos. Quatro bandas proteicas (81.5; 60.4; 33.6 e 25.5 kDa) foram detectadas em todas as amostras de plasma seminal analisadas. Uma banda proteica com peso molecular de 38.3 kDa foi associada com a baixa motilidade espermática no jundiá (P< 0,01), uma vez que foi detectada em 91.4% das amostras com motilidade menor que 80%. Estes resultados sugerem que esta banda proteica seminal associada com a baixa motilidade espermática poderá ser considerada como um potencial marcador bioquímico de qualidade seminal.

Protein factors have been identified in the seminal plasma of fish and mammal species and, in some situations, associated to sperm quality indicators. However, for jundiá fish (Rhamdia quelen), such factors and those potential associations remain unknown. In the present study, we aimed to identify some protein factors present in the seminal plasma of jundiá fish and to evaluate their association to sperm motility. SDS-PAGE was used to identify 14 bands, with molecular weight ranging from 217.1 to 7.1 kDa. Sperm motility was evaluated for 21 males. Four protein bands (81.5; 60.4; 33.6; and 25.5 kDa) were present in all seminal plasma samples. One protein band with molecular weight of 38.3 kDa was associated to reduced sperm motility of jundiá (P<0.01), since it was detected in 91.4% of the samples having motility lower than 80%. These results suggest that this seminal protein band associated to lower sperm motility may be considered a potential biochemical marker for sperm quality.

Immunoglobulins from human follicular fluid induce the acrosome reaction in human sperm.

The ability of human follicular fluid (hFF), retrieved from women undergoing IVF to induce the acrosome reaction (AR) in human sperm has been documented by several laboratories. However, the nature of the active factors in the hFF and the physiological meaning of the AR induction are highly controversial. We performed a three step purification scheme for hFF and all the fractions were screened for the AR-inducing activity. AR activity was associated with a protein fraction of M(r) > 180 kD that on further analysis under PAGE was found to be composed by subunits of apparent M(r) 50,000 and 29,000. The N-terminal sequences of these bands showed a 100% homology with the heavy and light chains of human IgG. A polyclonal antibody raised against the purified protein and anti-human IgG were both able to suppress the acrosome reaction-inducing activity of crude hFF. However, neither normal human serum nor a purified preparation of human IgG were able to mimic the AR-inducing activity of hFF. We concluded that the AR-inducing activity of hFF is, at least in part, due to the presence of antisperm antibodies.