Associação entre proteínas do plasma seminal, motilidade e viabilidade espermática em coelhos submetidos a doping genético / Association among seminal plasma proteins, sperm motility and sperm viability in rabbits submitted to gene doping

Neste trabalho foi estudada a correlação entre o perfil proteico do plasma seminal e a motilidade e viabilidade espermática em coelhos submetidos ao tratamento com vetores de expressão contendo o gene da eritropoetina (EPO) e com EPO recombinante humana. Foram identificadas, em coelhos submetidos ao tratamento com vetor de DNA contendo o gene da EPO, duas bandas proteicas associadas a alterações na motilidade espermática - 48kDa à baixa motilidade (P<0,05) e 18kDa à alta motilidade (P<0,05) - e esse fator foi associado a maior viabilidade espermática (P<0,05). Em coelhos submetidos ao tratamento com EPO recombinante, um fator proteico, 63kDa, associou-se à alta motilidade espermática (P<0,05), enquanto dois, 26 e 40kDa, foram associados à alta viabilidade espermática (P<0,05). Esses resultados sugerem que o doping genético pode ocasionar mudanças no perfil proteico do plasma seminal, provocando alterações na motilidade e viabilidade espermática.

In this study the correlation between seminal plasma protein profile and the sperm motility and sperm viability in rabbits submitted to treatment with an expression vector containing EPO gene and with human recombinant EPO was evaluated. In rabbits submitted to treatment with EPO expression vector, two protein bands were associated to sperm motility - 48kDa associated to low motility (P<0.05) and 18kDa to high motility (P<0.05) - and this protein band was also associated to high sperm viability (P<0.05). In rabbits submitted to treatment with human recombinant EPO, a protein factor, 63kDa, was associated to high sperm motility (P<0.05) while two protein factors, 26 and 40kDa, were associated to high sperm viability (P<0.05). These results suggest that gene doping leads to changes in rabbit seminal plasma protein, altering sperm motility and sperm viability.

Erythropoietin non-viral gene therapy does not affect motility, viability, morphology or concentration of rabbit sperm.

Erythropoietin (EPO) gene therapy can be used for several purposes; however, its effects on reproductive performance are unknown. The aim of this study was to evaluate the toxicological effects of non-viral (EPO) gene transfer on sperm motility, viability, morphology and concentration. Rabbit EPO cDNA was cloned into a pTarget mammalian expression vector. Rabbits were administered with: (1) pTarget/EPO vector, (2) recombinant human EPO (rHuEpo) and (3) saline (control). Both pTarget/EPO and rHuEpo significantly increased (P < 0.05) hematocrit levels 1 week after injection and they remained significantly higher than the control for up to 5 weeks (P < 0.05), showing that both EPO treatments were effective in stimulating the production of red blood cells in rabbits. The EPO gene transfer or rHuEPO administration had no significant effect (P > 0.05) on sperm motility, vigor, viability, concentration or morphology in the testis.

NanoSMGT: transfection of exogenous DNA on sex-sorted bovine sperm using nanopolymer.

The objective was to introduce exogenous DNA into commercially sex-sorted bovine sperm using nanopolymer for transfection. In the first experiment, the optimal concentration and ratio of linear-to-circular plasmid was determined for NanoSMGT in unsorted sperm. A second experiment was conducted to transfect exogenous DNA into sex-sorted sperm. Exogenous DNA uptake occurred in a dose-dependent manner (P < 0.05). The optimal amount of DNA was 10 µg/10(6) cells. The ratios of linear-to-circular plasmid do not influence the uptake by unsorted sperm cells and none of the tested treatments affected sperm motility and viability. Commercially sex-sorted bovine sperm were able to uptake exogenous DNA using nanopolymer; however, both X- and Y-sorted sperm had decreased DNA uptake in comparison to unsorted sperm (P < 0.05). Neither sperm motility nor viability were affected by nanotransfection. In conclusion, nanopolymer efficiently introduced exogenous DNA into commercially sex-sorted bovine sperm; we inferred that these sperm could be used for production of embryos of the desired sex, a technique named NanoSMGT.