Role of Nitric Oxide Concentrations on Human Sperm Motility

788 MALE INFERTILITY Role of Nitric Oxide Concentrations on Human Sperm Motility G. BALERCIA, S. MORETTI, A. VIGNINI, M. MAGAGNINI, F. MANTERO, M. BOSCARO, G. RICCIARDO-LAMONICA AND L. MAZZANTI, Endocrinology Division, Department of Internal Medicine, Department of Economy, School of Economy and Department of Biochemistry, University of Ancona, Ancona, Department of Biomedical and Surgical Sciences, University of Verona, Verona and Endocrinology Division, Department of Medical and Surgical Sciences, University of Padua, Padua, Italy J Androl, 25: 245–249, 2004 Nitric oxide (NO) is a free radical generated from the oxidation of L-arginine to L-citrulline by 3 isoforms of reduced nicotinamide adenine dinucleotide phosphate (NADPH)-dependent NO synthases. Several data suggest a relevant role in sperm cell pathophysiology, but any conclusive data on its role in spermatozoa motility are still lacking. In the present study, we have correlated NO concentration in semen and kinetic features of sperm cells from normozoospermic fertile donors and infertile patients affected by idiopathic asthenozoospermia. Normozoospermic fertile men exhibited NO concentrations that were significantly lower than those of asthenozoospermic infertile men. A significant linear negative correlation was evident between NO concentration and percentage of total sperm motility. A further significant linear negative correlation was found between NO concentration and spermatozoa kinetic characteristics determined by a computerized analysis (curvilinear and straight progressive velocity). These data suggest that the overproduction of this free radical and the consequent excessive exposure to oxidative conditions have a potential pathogenetic implication in the reduction of sperm motility. The positive role played by NO in spermatozoa capacitation leads us to speculate that such paradoxical involvement in both pathologic and physiologic processes depends on the alternative redox state and relative level of NO. Editorial Comment: Nitric oxide is well known in urology as a neurotransmitter responsible for cavernous smooth muscle relaxation and ultimately an erection. Nitric oxide is a free radical that is generated from the oxidation of L-arginine. It has a multitude of physiological functions. Previous studies in the mouse have shown that sperm produce NO and that it may be involved in sperm capacitation and the acrosome reaction. The current study demonstrates an inverse relationship between seminal NO levels and percent sperm motility. This crude assessment suggests that NO may have an adverse effect on sperm motility due to oxidative damage. However, this study design does not preclude the possibility that this observation is just an association rather than cause and effect. Clearly, a great deal more needs to be learned about the physiological effects of NO in male reproduction. Jonathan P. Jarow, M.D.

Recombinant Human Follicle-Stimulating Hormone as a Pretreatment for Idiopathic Oligoasthenoteratozoospermic Patients Undergoing Intracytoplasmic Sperm Injection E. CAROPPO, C. NIEDERBERGER, G. M. VIZZIELLO AND G. D’AMATO, IRCCS “S. de Bellis,” Castellana Grotte (Ba), Italy Fertil Steril, 80: 1398 –1403, 2003 Objective: To evaluate the efficacy of recombinant human FSH pretreatment in improving fertilization and pregnancy rates in oligozoospermic patients who are undergoing ICSI. Design: Prospective, controlled, clinical study. Setting: A research institute’s reproductive unit. Patient(s): Thirty-three subjects with idiopathic oligoasthenoteratozoospermia who failed to conceive after previous ICSI attempts. Intervention(s): Treatment with recombinant human FSH 150 IU for 3 months (23 patients) or no treatment (10 patients); clinical, hormonal, and seminal evaluation before and after treatment. Main Outcome Measure(s): Testicular volume, sperm parameters, FSH, LH, T, E2, and inhibin B plasma levels, E/T ratio, and fertilization and pregnancy rates. Result(s): Treatment with 150 IU of FSH induced a significant increase in testicular volume and sperm parameters. The mean fertilization rate (FR) after ICSI cycles was higher, although not significantly, in treated patients when compared with controls (62.3 ⫾ 22.4 vs. 47.2 ⫾ 20.4). A strong negative correlation was observed between FR and serum FSH, inhibin B and E/T ratio in controls, whereas in treated patients, FR correlated with posttreatment inhibin B levels. The pregnancy rate in the entire treated group was 30.4%. No pregnancies were recorded in the control group. Conclusion(s): Recombinant human FSH may be a valuable pretreatment for oligozoospermic patients undergoing ICSI and may influence testicular paracrine activity. Editorial Comment: The exact role of follicle-stimulating hormone (FSH) in male reproduction is not known, but there is significant evidence to suggest that FSH has an important role in the