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why. Once again, the brainiacs look over here when they need to look over there where they aren't supposed to. Association between mental stress & some antioxidant enzymes of seminal plasma. Eskiocak S, Gozen AS, Kilic AS, Molla S. Department of Biochemistry, Trakya University, School of Medicine Edirne, Turkey. [email protected]BACKGROUND & OBJECTIVE: Mental stress, which is responsible for various disorders, is one of the most important medical and social problems. It is reported that mental stress causes abnormality in sperm quality. Most of the previous investigations done to study the association between mental stress and infertility were carried out with infertile men. Infertility itself and/or its therapy may lead to stress. Further, most studies investigating the association between psychological stress and semen quality have lacked information on biochemical parameters. In the present study, we investigated the effect of mental stress due to final exams on two important antioxidant enzymes of the seminal plasma, superoxide dismutase (SOD) and catalase in normal healthy medical students. METHODS: Semen samples were collected from 27 healthy male volunteers, who were third semester students of a medical school, just before (stress period) and 10.19+/-0.83 wk after (non-stress period) the final examinations. Psychological stress of participants was measured by the State Trait Anxiety Inventory. After standard semen analysis, semen samples were centrifuged at 10,000 x g for 15 min. Superoxide dismutase (SOD) and catalase activities were measured in the seminal plasma. RESULTS: During stress period, stress scores and SOD activities increased significantly compared to the non-stress period. Catalase activities showed no change. Spermatozoa concentrations, motility index and percentage of rapid progressive motility decreased under stress. INTERPRETATION & CONCLUSION: Our results indicated that mental stress negatively affected semen quality. Increase in SOD activities led to poor quality of semen parameters. PMID: 16517999
1: Reprod Biomed Online. 2005 Nov;11(5):641-50. Related Articles, Links
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Oxidative stress and its implications in female infertility - a clinician's perspective.
Agarwal A, Gupta S, Sharma R.
Centre for Advanced Research in Human Reproduction, Infertility, and Sexual Function, Department of Obstetrics-Gynecology and Glickman Urological Institute, The Cleveland Clinic Foundation, OH 44195, USA. [email protected]
Reactive oxygen species (ROS) have a role in the modulation of gamete quality and gamete interaction. Generation of ROS is inherent in spermatozoa and contaminating leukocytes. ROS influence spermatozoa, oocytes, embryos and their environment. Oxidative stress (OS) mediates peroxidative damage to the sperm membrane and induces nuclear DNA damage. ROS can modulate the fertilizing capabilities of the spermatozoa. There is extensive literature on OS and its role in male infertility and sperm DNA damage and its effects on assisted reproductive techniques. Evidence is accumulating on the role of ROS in female reproduction. Many animal and human studies have elucidated a role for ROS in oocyte development, maturation, follicular atresia, corpus luteum function and luteolysis. OS-mediated precipitation of pathologies in the female reproductive tract is similar to those involved in male infertility. OS influences the oocyte and embryo quality and thus the fertilization rates. ROS appears to play a significant role in the modulation of gamete interaction and also for successful fertilization to take place. ROS in culture media may impact post-fertilization development, i.e. cleavage rate, blastocyst yield and quality (indicators of assisted reproduction outcomes). OS is reported to affect both natural and assisted fertility. Antioxidant strategies should be able to intercept both extracellular and intracellular ROS. This review discusses the sources of ROS in media used in IVF-embryo transfer and strategies to overcome OS in oocyte in-vitro maturation, in-vitro culture and sperm preparation techniques.
Publication Types:
* Review
PMID: 16409717
1: Indian J Exp Biol. 2005 Nov;43(11):963-74. Related Articles, Links
Mechanism, measurement, and prevention of oxidative stress in male reproductive physiology.
Agarwal A, Prabakaran SA.
Center for Advanced Research in Human Reproduction, Infertility, and Sexual Function, Glickman Urological Institute, and Department of Obstetrics and Gynecology, The Cleveland Clinic Foundation, Ohio, 44195, USA. [email protected]
Numerous factors influence male fertility. Among these factors is oxidative stress (OS), which has elicited an enormous interest in researchers in recent period. Reactive oxygen species (ROS) are continuously produced by various metabolic and physiologic processes. OS occurs when the delicate balance between the production of ROS and the inherent antioxidant capacity of the organism is distorted. Spermatozoa are particularly sensitive to ROS as their plasma membrane contains polyunsaturated fatty acids (PUFA), which oxidizes easily. They also lack cytoplasm to generate a robust preventive and repair mechanism against ROS. The transition metal ions that are found in the body have a catalytic effect in the generation of ROS. Lifestyle behaviours such as smoking and alcohol use and environmental pollution further enhance the generation of ROS and thus, cause destructive effects on various cellular organelles like mitochondria, sperm DNA etc. This article analyzes the detrimental effects of OS on male fertility, measurement of OS and effective ways to decrease or eliminate them completely. We have also provided information on oxidative stress in other systems of the body, which may be applied to future research in the field of reproductive biology.
Publication Types:
* Review
PMID: 16315393
1: Curr Drug Metab. 2005 Oct;6(5):495-501. Related Articles, Links
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Mechanisms of male infertility: role of antioxidants.
Sheweita SA, Tilmisany AM, Al-Sawaf H.
Department of Clinical Biochemistry, Faculty of Medicine, PO Box 30001, Taibah University, Madinah, Saudi Arabia. [email protected]
Defective sperm function is the most common cause of infertility, and until recently, was difficult to evaluate and treat. Mammalian spermatozoa membranes are rich in poly unsaturated fatty acids and are sensitive to oxygen induced damage mediated by lipid peroxidation. Hence, free radicals and reactive oxygen species are associated with oxidative stress and are likely to play a number of significant and diverse roles in reproduction. The excessive generation of reactive oxygen species by abnormal spermatozoa and by contaminating leukocytes has been identified as one of the few defined etiologies for male infertility. Moreover, environmental factors, such as pesticides, exogenous estrogens, and heavy metals may negatively impact spermatogenesis since male sperm counts were declined. In addition, aging is also likely to further induce oxidative stress. Limited endogenous mechanisms exist to reverse these damages. In a normal situation, the seminal plasma contains antioxidant mechanisms which are likely to quench these ROS and protect against any likely damage to spermatozoa. However, during genitourinary infection/inflammation these antioxidant mechanisms may downplay and create a situation called oxidative stress. Assessment of such oxidative stress status may help in the medical treatment of male infertility by suitable antioxidants. The cellular damage in the semen is a result of an improper balance between ROS generation and scavenging activities. Therefore, numerous antioxidants such as vitamin C, vitamin E, glutathione, and coenzyme Q10, have proven beneficial effects in treating male infertility. A multi-faceted therapeutic approach to improve male fertility involves identifying harmful environmental and occupational risk factors, while correcting underlying nutritional imbalances to encourage optimal sperm production and function.
Publication Types:
* Review
PMID: 16248841 |
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