Studies on the origin of redox enzymes in seminal plasma and their relationship with results of in-vitro fertilization

Abstract

Glutathione (GSH), GSH peroxidase (GPX), GSH reductase (GRD), superoxide dismutase (SOD) and catalase-like enzyme activity were quantified in seminal plasma from normozoospermic patients, men with known distal ductal occlusion, proven fathers and male partners of couples receiving in-vitro fertilization (IVF) treatment for both male and female causes. Glutathione was non-detectable (< 2.5 microM) in seminal plasma. None of the enzyme activities per unit volume were lower in semen from vasectomized men, suggesting that they did not originate substantially from the testis or epididymis. The strongest relationships between enzyme activities and accessory gland markers were between zinc and GRD (r = 0.678), SOD (r = 0.602) and GPX (r = 0.548), suggesting a largely prostatic origin of these enzymes. Only weak relationships between accessory gland markers and catalase-like activity suggested a multi-glandular source of this enzyme. There was no relationship between the activity of any of the enzymes in the IVF patients with their fertilization rates in vitro or the establishment of pregnancy after IVF. Nor was there any correlation of enzyme activity with the morphology and percentage of motile spermatozoa in semen or with the percentage motility of spermatozoa immediately after swim-up or after overnight incubation. These findings suggest that the protective enzymes in the seminal plasma are contributed largely by the prostate and little by the epididymis, and that in most cases of IVF, they have no major influence on the outcome.

Zinc and Iron Concentration and SOD Activity in Human Semen and Seminal Plasma

“…Additionally, a significant correlation between SOD activity and Zn concentration (this paper) was also stated, and this finding confirms the report of Yeung et al [43]. This correlation might be explained by the prostatic origin of SOD, especially of tissue-specific Cu-Zn from SOD [44].…”

Glutathione peroxidase activity in seminal plasma and its relationship to classical sperm parameters and in vitro fertilization-intracytoplasmic sperm injection outcome

“…It was not, however, possible in this study to ascertain whether low GPX levels along the male reproductive tract are responsible for the aforementioned structural and functional abnormalities or whether the increased production of ROS by abnormal spermatozoa and the subsequent oxidative injury reduces GPX activity in seminal plasma. It has been suggested that peroxidative damage to spermatozoa may be exacerbated in assisted reproduction techniques that involve washing spermatozoa, thereby removing enzymes present in seminal plasma and then subjecting them to prolonged incubation in the absence of these potentially protective enzymes (30). In agreement with this, it has been reported that addition of an antioxidant to semen during liquefaction has a protective effect on sperm motility (34).…”

“…Although a number of studies have investigated the relationship between human seminal plasma GPX and semen parameters, results have not been consistent. Lower GPX levels have been reported among infertile men (27,28), as well as in patients with asthenozoospermia (29), while in other studies no relationship between these parameters was detected (30)(31)(32), and, surprisingly, in another study, higher levels of GPX were reported in males with oligozoospermia or asthenozoospermia (33). These discrepancies may be explained by sample sizes.…”

Semen quality and fertility in adult long-term survivors of childhood acute lymphoblastic leukemia

“…(neutral a-glucosidase, zinc, fructose) were measured at the Centre of Reproductive Medicine and Andrology, University of M€ unster with multiwell spectrophotometric assays, as previously described elsewhere (14).…”