BackgroundSpermatozoa are extremely vulnerable to oxidative stress caused by the unbalance between concentrations of reactive oxygen species and antioxidant scavenging systems present inside the male reproductive tract. In spite of a large number of clinical studies that claimed the beneficial effects of antioxidant oral administration on sperm physiology and fertility, only a few studies were addressed to evaluate their effects on spermatozoa in vitro. Main aims of the present study were to assess the influence of zinc, D-aspartate and coenzyme Q10, included in the dietary supplement Genadis (Merck Serono), on human sperm motility, DNA fragmentation and lipid peroxidation.MethodsSemen samples, obtained from forty-four patients (23–30 years of age) were enrolled in this study, twenty-four were normospermic and twenty patients were oligospermic. Semen samples were analysed for sperm progressive motility and kinetics through computer assisted analysis, DNA fragmentation and lipid peroxidation.ResultsMain results showed that in both normo and oligospermic samples, total and progressive sperm motility is maintained by in vitro treatment with zinc, D-aspartate and coenzyme Q10, whereas a significant decrease of these parameters occurs in parallel samples incubated in medium alone. Zinc, D-aspartate and coenzyme Q10 also prevented the decrease of sperm kinetics but such an effect was highly significant only in oligospermic samples. Moreover, they also protected spermatozoa by the increase of DNA fragmentation and lipid peroxidation.ConclusionsZinc, D-aspartate and coenzyme Q10 exert a direct protective effect on human spermatozoa preventing the decrease of motility and the increase of DNA fragmentation and lipid peroxidation during in vitro culture.

The phylogenetic enigma of snail hemoglobin, its isolated occurrence in a single gastropod family, the Planorbidae, and the lack of sequence data, stimulated the present study. We present here the complete cDNA and predicted amino acid sequence of two hemoglobin polypeptides from the planorbid Biomphalaria glabrata (intermediate host snail for the human parasite Schistosoma mansoni). Both isoforms contain 13 different, cysteine-free globin domains, plus a small N-terminal nonglobin ''plug'' domain with three cysteines for subunit dimerization (total M r Ϸ 238 kDa). We also identified the native hemoglobin molecule and present here a preliminary 3D reconstruction from electron microscopical images (3 nm resolution); it suggests a 3 ؋ 2-mer quaternary structure (M r Ϸ 1.43 MDa). Moreover, we identified a previously undescribed rosette-like hemolymph protein that has been mistaken for hemoglobin. We also detected expression of an incomplete hemocyanin as trace component. The combined data show that B. glabrata hemoglobin evolved from pulmonate myoglobin, possibly to replace a less-efficient hemocyanin, and reveals a surprisingly simple evolutionary mechanism to create a high molecular mass respiratory protein from 78 similar globin domains.

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Transplantation of ovarian tissue for the preservation of fertility in oncological patients is becoming an accepted clinical practice. However, the risk of re-introducing tumour cells at transplantation has stirred an increased interest for complete in vitro folliculogenesis. This has not yet been achieved in humans possibly for the lack of knowledge on the environmental milieu that orchestrates folliculogenesis in vivo. The main aim of this study was to investigate the effect of oxygen availability on follicle health and growth during in vitro culture of ovarian tissue strips. To this end, a model was developed to predict the dissolved oxygen concentration in tissue under varying culture conditions. Ovarian cortical strips of bovine, adopted as an animal model, and human tissue were cultured in conventional (CD) and gas permeable (PD) dishes under different media column heights and gaseous oxygen tensions for 3, 6 and 9 days. Follicle quality, activation of primordial follicles to the primary stage, and progression to the secondary stage were analysed through histology. Follicle viability was assessed through a live-dead assay at the confocal scanning laser microscope. Findings showed a higher follicle quality and viability after culture of bovine ovarian strips in PD in adequate medium height and oxygen tensions. The best culture conditions found in the bovine were adopted for human ovarian strip culture and promoted a higher follicle quality, viability and progression. Overall, data demonstrated that modulation of oxygen availability in tissue plays a key role in maintaining follicles’ health and their ability to survive and progress to the secondary stage during ovarian tissue in vitro culture. Such culture conditions could increase the yield of healthy secondary follicles for subsequent dissection and individual culture to obtain competent oocytes.

High levels of reactive oxygen species in the semen of infertile patients or spontaneously generated during in vitro sperm handling may impair sperm quality, fertilization and embryo developmental competence. We recently reported that zinc, d-aspartate and co-enzyme Q10, contained in the dietary supplement Genadis® (Merck Serono), have protective effects on human and bull sperm motility, lipid peroxidation and DNA fragmentation in vitro; furthermore, in bovine, treated spermatozoa had an improved ability to support embryo development. However, only a few studies have investigated the protective role of antioxidants during in vitro sperm handling in the presence of an exogenous oxidative stress. Herein, to simulate such conditions in an animal model, we induced exogenous oxidative stress on spermatozoa through the xanthine-xanthine oxidase system and investigated its effects on sperm function and subsequent embryo developmental competence in the presence of zinc, d-Asp and CoQ10 protection. The main results showed that exogenous oxidative stress decreased sperm motility, increased sperm DNA fragmentation, and reduced fertilization and blastocyst rates and quality. Pre-treatment with zinc, d-aspartate and co-enzyme Q10 before exogenous oxidative stress was able to prevent these effects. Supplementation of sperm culture media with zinc, d-aspartate and co-enzyme Q10 could protect sperm from oxidative stress damage during in vitro handling in assisted reproductive technologies.

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