Semen

About: Semen is a research topic. Over the lifetime, 14571 publications have been published within this topic receiving 407739 citations. The topic is also known as: come & ejaculate.

Protective role of isoflavones against the toxic effect of cypermethrin on semen quality and testosterone levels of rabbits.

Abstract: Cypermethrin is considered as one of the endocrine disruptors. Isoflavones play an important role in various physiological processes in the body. It has both estrogenic and antioxidant effects. The objective of this study was to evaluate the protective role of isoflavones (2 mg/kg B.W) on semen quality and plasma testosterone levels of male New Zealand White rabbits given sublethal dose (24 mg/kg BW every other day for 12 weeks) of cypermethrin. Results showed that treatment with cypermethrin caused a significant decreases (P < 0.05) in ejaculate volume, sperm concentration, total sperm output, sperm motility (%), total motile sperm per ejaculate (TMS), packed sperm volume (PSV), semen initial fructose and plasma testosterone. In addition, live body weight (LBW), dry matter intake (DMI) and relative weights of testes and epididymis were decreased. On the other hand, treatment with cypermethrin increased (P < 0.05) the numbers of abnormal and dead sperms, and initial hydrogen ion concentration (pH). Results indicated that the presence of isoflavones together with cypermethrin was capable to minimize its harmful effects. Treatment with isoflavones alone had positive effects on some semen characteristics in spite of it is considered as estrogen-like compound. Since it causes significant increases in libido (by decreasing the reaction time), PSV, sperm motility and TMS, while abnormal and dead sperm were reduced compared to control animals. Meanwhile, isoflavones had no negative effect on ejaculate volume, total sperm output, sperm concentration, initial fructose concentration, pH and plasma testosterone levels. Results demonstrated the beneficial influences of isoflavones in reducing the negative effects of cypermethrin on reproductive characteristics of mature male rabbits. Interestingly, data showed that isoflavones alone caused an improvement in some semen quality and had no negative effects on male fertility, and did not have negative effects on male fertility.

Clomiphene Administration for Cases of Nonobstructive Azoospermia: A Multicenter Study

Abstract: Clomiphene citrate is a well-established agent thathas been empirically used in cases of idiopathic oligospermia. Clo-miphene increases endogenous gonadotropin-releasing hormonesecretion from the hypothalamus and gonadotropin hormone secre-tion directly from the pituitary and, thus, increases intratesticulartes-tosterone concentration. Using intracytoplasmic sperm injection(ICSI), very few sperm may be required for fertilization.Theobjectiveof this study was to determine if the application of clomiphenecitratein males with nonobstructive azoospermia might produce sufficientsperm for ICSI, either by resulting in sperm identified in the ejaculateor by potentially improving outcomes of surgical testicular sperm ex-traction. Forty-two patients with nonobstructive azoospermia (agerange, 25–39 years) from 3 international centers were evaluatedwithroutine history, physical examination, and hormonal assessment.Ini-tial testicular biopsy demonstrated maturation arrest in 42.9% andhypospermatogenesis in 57.1% of patients. Clomiphene citrate wasadministered, with the dose titrated to achieve serum testosteronelevels between 600 ng/dL and 800 ng/dL, and semen analyses wereperformed at periodic intervals. In patients remaining azoospermicon semen analysis, surgical testicular biopsy and sperm extractionwere performed. After clomiphene citrate therapy, 64.3% of the pa-tients demonstrated sperm in their semen analyses ranging from 1to 16 million sperm/mL, with a mean sperm density of 3.8 million/mL. Sufficient sperm for ICSI was retrieved by testicular sperm ex-traction in all patients, even though 35.7% remained azoospermic.Additionally, clomiphene citrate administration resulted in a statisti-cally significant increase in testis biopsy patterns associated withgreater likelihood of sperm obtained by surgical extraction (P, .05).We conclude that clomiphene citrate administration may result insperm in the ejaculate of patients with nonobstructive azoospermiaor the simplification of testis sperm retrieval. Surgeons may considera course of clomiphene citrate administration prior to surgical spermretrieval in patients with nonobstructive azoospermia.Key words: Hypospermatogenesis, maturation arrest, ICSI,TESE.J Androl 2005;26:787–791

The protective effects of melatonin against cryopreservation-induced oxidative stress in human sperm:

Abstract: Reactive oxygen species (ROS) production and lipid peroxidation during cryopreservation harm sperm membrane and as a result reduce the recovery of motile sperm. The antioxidant effects of melatonin on different cells have been widely reported. This study was aimed to evaluate changes in post-thaw motility, viability, and intracellular ROS and malondialdehyde (MDA) in response to the addition of melatonin to human sperm freezing extender. Semen of 43 fertile men was collected and each sample was divided into eight equal aliquots. An aliquot was analyzed freshly for viability, motility, and intracellular ROS and MDA. Melatonin was added to the recommended human freezing extender to yield six different final concentrations: 0.001, 0.005, 0.01, 0.05, 0.1, and 1 mM. A control group without melatonin was also included. Two weeks after cryopreservation, samples were thawed and pre-freeze analyses repeated. Obtained results showed that cryopreservation significantly (P <0.05) reduces viability and motility, but increases intracellular ROS and MDA of human sperm. The semen extender supplemented with various doses of melatonin (except for 0.001 mM) significantly (P <0.05) increased motility and viability, but decreased intracellular ROS and MDA levels of cryopreserved sperm after the thawing process, as compared with the control group. We also found that the most effective concentration of melatonin in protecting human spermatozoa from cryopreservation injuries was 0.01 mM. These findings suggest that melatonin exerts its cryoprotective effects on spermatozoa possibly by counteracting intracellular ROS, and thereby reduces MDA generation. This finally leads to increase of post-thaw viability and motility of cryopreserved spermatozoa.