International Journal of Fertility & Sterility
Year:2009 | Volume:3 | Issue:3|Papers Count:8

Spermatozoa generate reactive oxygen species (ROS) in physiological amounts, which play a role in sperm functions during sperm capacitation, acrosome reaction (AR), and oocyte fusion. In addition, damaged sperm are likely to be the source of ROS. The most important ROS produced by human sperm are hydrogen peroxide, superoxide anion and hydroxyl radicals. Besides, human seminal plasma and sperm possess an antioxidant system to scavenge ROS and prevent ROS related cellular damage. Under normal circumstances, there is an appropriate balance between oxidants and antioxidants. A shift in the levels of ROS towards pro-oxidants in semen can induce  oxidative stress (OS) on spermatozoa. Male infertility is associated with increased ROS and decreased total antioxidant activity in the seminal plasma. ROS induce nuclear DNA strand breaks. Besides, due to a high polyunsaturated fatty acid content human sperm plasma membranes are highly sensitive to ROS induced lipid peroxidation thus decreasing membrane fluidity. This will result in increased lipid peroxidation (LPO), decreased sperm motility, viability, function and ultimately lead to infertility. The protective action of antioxidants against the deleterious effect of ROS on cellular lipids, proteins and DNA has been supported by several scientific studies. The purpose of the present review is to address the possible relationship between ROS and antioxidants production in seminal plasma, and the role they may play in influencing the outcome of assisted reproductive technology (ART).

Background: An evaluation of the developmental competence of vitrified mouse germinal vesicle (GV) oocytes with various equilibration and vitrification times; in the presence or absence of cumulus cells and by comparison between the cryotop method and straws was performed.Materials and Methods: Mouse GV oocytes were considered in cumulus-denuded oocytes (CDOs) and cumulus-oocyte complexes (COCs) groups. Their survival and developmental rates were studied in the following experiments: (I) exposure to different equilibration times (0, 3 and 5 minutes) and vitrification (1, 3 and 5 minutes) without plunging in LN2 as toxicity tests, (II) oocytes were vitrified using straws followed by exposure to equilibration solution for 0, 3 and 5 minutes and vitrification solution for 1 and 3 minutes, and (III) oocytes were vitrified by cryotop following exposure to equilibration for 5 minutes and vitrification for 1 minute, respectively.Results: Maturation and developmental rates of the COCs were higher than CDOs in the non-vitrified group (p<0.05). The survival and maturation rates were low in all oocytes exposed to vitrification solution for 5 minutes (p <0.05). In vitrified CDOs and COCs using straws, the survival rates ranged from 56.9% to 85.4% and 44.0% to 84.5%, and the maturation rates from 35.3% to 56.8% and 25.8% to 56.2%, respectively; which were lower than non-vitrified samples (p <0.05). Cryotop vitrified oocytes showed higher survival, maturation and fertilization rates when compared to straw in both CDOs and COCs (p <0.05).Conclusion: The presence of cumulus cells improves developmental competence of GV oocytes in control groups but it did not affect the vitrified group. Vitrification of mouse GV oocytes using cryotop was more effective than straws, however both vitrification techniques did not improve the cleavage rate.

Background: To attain whether the effects of low and high doses of estrogen, progesterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) in acute and chronic administration were related to oxidant and antioxidant parameters in rat uterine tissue as well as cyclooxygenase-1 (COX-1) activity.Materials and Methods: Acute and chronic administration of estrogen (1 and 5 mg/kg), progesterone (1 and 5 mg/kg), LH (20 U/kg), and FSH (250 U/kg). A combination of mifepristone (50 mg/kg) with progesterone (5 mg/kg) and FSH (250 U/kg); and yohimbine (10 mg/kg) with estrogen (5 mg/kg) and LH (20 U/kg). Measurement total glutathione, nitric oxide levels and malondialdehyde, myeloperoxidase and COX-1 activities.Results: Acute and chronic administration of progesterone 5 mg/kg and FSH 250 U/kg; and chronic administration of estrogen 1 mg/kg decreased antioxidants and increased oxidants. Combined administration of yohimbine with estrogen and LH showed the effect on these parameters.Conclusion: While LH had a protective effect, low chronic dose estrogen caused oxidative stress. Because low doses could not stimulate alpha-2 receptors and it inhibited LH, an antioxidant hormone. High doses of estrogen that stimulated alpha-2 receptors showed a stable trend in oxidant and antioxidant levels in both acute and chronic administration. High doses of progesterone had an oxidant effect when it stimulated its own receptor in acute and chronic administration. In low acute and chronic doses, though progesterone could not stimulate its receptors but could inhibit FSH, it showed no effect. The oxidant effects of progesterone and FSH were blocked by mifepristone.

Background: Chlamydia trachomatis is considered as an important cause of preventable sexually transmitted diseases, worldwide. It is known to be of an obligate intracellular nature and enters its target cells via an endocytic process. As major outer membrane protein (MOMP) is one of the main candidates for the attachment and entry of chlamydia to the host cells, we have tried to label the epitopes by using different techniques.Materials and Methods: McCoy cells were experimentally inoculated with 104 elementary bodies (EBs) followed by 24 hours incubation at 37°C. The infected cells were then processed for direct fluorescent antibody (DFA) and transmission electron microscopy (TEM) using anti-MOMP antibody and pre- and post-embedded labelling techniques.Results: DFA was able to detect 11/11 (100%) of the infected cells. These values were recorded as 9/11 (81.81%) and 8/11 (72.72%), using pre- and post-embedded techniques, respectively.Conclusion: MOMP is proposed to be one of the most important adhesion molecules for chlamydial attachment and entry into host cells.

Background: Imatinib is used in chronic myelogenous leukemia (CML), gastrointestinal stromal tumors (GISTs) and a number of other malignancies.  The major aim of this study was to investigate the effects of Imatinib on male fertility in Wistar rats. Materials and Methods: Three groups of rats were gavaged with 6, 9, and 12 mg/kg Imatinib dissolved in dH2O for 30 consecutive days. On days 7, 14 and 30, blood samples were collected and LH, FSH, and testosterone levels were measured by the ELISA method. The numbers of sperm located in the epididymis were counted by staining with aqueous Eosin Y. Other sections of the testes were stained with H & E, investigated histologically, and the results were statistically analyzed. Results: On day 7 of the experiment, testosterone concentrations in the experimental groups were decreased (p £ 0.01), LH and FSH increased significantly, and the number of sperm in both the epididymis and sertoli cells decreased (p £ 0.01). There was an increase in tunica albuginea thickness (p  £ 0.05) but the diameter of the seminiferous tubules showed a significant decrease (p £ 0.01). There was also a decrease in the number of Leydig cells, spermatogonia, stem cells, primary spermatocyte and spermatid.  In the second and third samples (14 and 30 days after treatment), the testosterone levels, numbers of spermatogenic cells, Sertoli and Leydig cells showed an increase when compared to the first sample. Conclusion: These findings suggest that a dose dependent administration of Imatinib has a profound effect on spermatogenesis.

Background: The purpose of this study was to investigate the role of Chlamydia serology as a screening test for tubal infertility and to compare the results with hysterosalpingography (HSG) and laparoscopic findings.Materials and Methods: This was a cross-sectional study undertaken on 110  infertile women treated in the IVF Ward, at Emam Khomeini Hospital, Sari, Iran who underwent laparoscopy and HSG as part of their infertility worku. Prior to laparoscopy, 5 ml of venous blood was drawn for measurement of serum Chlamydia IgG antibody titer (CAT). Patients’ tubal status and pelvic findings were compared with CAT, as measured by microimmunofluorescence.Results: Tuboperitoneal abnormalities were seen in 81.4% of seropositive patients versus 13.2% of women who were seronegative.  In women with tubal damage, the numbers of positive CATs (³1:32) were significantly more than in those who had a normal pelvis (66.6% vs. 6.5%, p<0.001). CAT levels were higher in patients who had bilateral hydrosalpinges, bilateral tubal occlusion and pelvic adhesions (severe damage), than those with tubal distortion and unilateral occlusion (mild damage) (p<0.05).  The positive likelihood ratio for C. trachomatis antibody testing was 10.28 as compared with HSG, which had a positive likelihood ratio of 3.03.Conclusion: The results of this study revealed that C. trachomatis serology is an inexpensive and non-invasive test for tubal factor infertility screening.

Background: Egg yolk is the main cryoprotectant agent in semen freezing extenders which is used in order to protect spermatozoa against cold shock. However, elimination of animal bioproducts from the cryopreservation protocol is becoming mandatory. Therefore, the aim of this study is to compare a previously studied, homemade soya bean lecithin based extender with a commercially available extender for ram sperm cryopreservation. Materials and Methods: Samples from three rams were pooled and split into two equal aliquots and diluted (1:20) with i%lecithin - 7%glycerol (L1G7) and Bioxcell®. The effects of L1G7 and Bioxcell® on sperm parameters and the in vitro fertilization ability of frozen-thawed ram spermatozoa were assessed. Results: The results of this study revealed no difference between the two extenders in terms of motility, viability, and capacitation status. The results of in vitro fertilization in terms of rate of blastocyst formation were similar for both extenders, but significantly lower than that of freshly processed ram sperm. Conclusion: We conclude that both extenders are suitable for ram sperm cryopreservation.

The prolonged retention of fetal bone structure is an uncommon condition after a previous abortion. We describe two cases with fetal bone fragment amongst 3589 hysteroscopies (0.05%), who had no complaint other than secondary infertility. In both patients, hyperechogenic areas were found through transvaginal ultrasound and the bones were removed by hysteroscopy. Despite meticulous evaluation during hysteroscopy, some bones were not observed and were stable during the next sonography. According to the formation of fetal bones after 11 weeks of pregnancy; patients with secondary infertility who have a history of abortion that progressed beyond this time and endometrial hyperechoic areas by transvaginal ultrasound should be evaluated for any retained fetal bone. Hysteroscopy should be performed under abdominal ultrasonography guide to ensure fetal bone tissue is entirely removed during a single surgery.