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Esteves SC, Coimbra I, Hallak J. Surgically retrieved spermatozoa for ICSI cycles in non-azoospermic males with high sperm DNA fragmentation in semen. Andrology 2023; 11:1613-1634. [PMID: 36734283 DOI: 10.1111/andr.13405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/16/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023]
Abstract
Intracytoplasmic sperm injection (ICSI) using surgically retrieved spermatozoa outside the classic context of azoospermia has been increasingly used to overcome infertility. The primary indications include high levels of sperm DNA damage in ejaculated spermatozoa and severe oligozoospermia or cryptozoospermia, particularly in couples with ICSI failure for no apparent reason. Current evidence suggests that surgically retrieved spermatozoa for ICSI in the above context improves outcomes, mainly concerning pregnancy and miscarriage rates. The reasons are not fully understood but may be related to the lower levels of DNA damage in spermatozoa retrieved from the testis compared with ejaculated counterparts. These findings are consistent with the notion that excessive sperm DNA damage can be a limiting factor responsible for the failure to conceive. Using testicular in preference of low-quality ejaculated spermatozoa bypasses post-testicular sperm DNA damage caused primarily by oxidative stress, thus increasing the likelihood of oocyte fertilization by genomically intact spermatozoa. Despite the overall favorable results, data remain limited, and mainly concern males with confirmed sperm DNA damage in the ejaculate. Additionally, information regarding the health of ICSI offspring resulting from the use of surgically retrieved spermatoa of non-azoospermic males is still lacking. Efforts should be made to improve the male partner's reproductive health for safer ICSI utilization. A comprehensive andrological evaluation aiming to identify and treat the underlying male infertility factor contributing to sperm DNA damage is essential for achieving this goal.
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Affiliation(s)
- Sandro C Esteves
- ANDROFERT, Andrology and Human Reproduction Clinic, Av. Dr. Heitor Penteado, Campinas, SP, Brazil
- Department of Surgery (Division of Urology), Faculty of Medical Sciences, University of Campinas (UNICAMP), Campinas, SP, Brazil
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Igor Coimbra
- Department of Surgery, Division of Urology, University of São Paulo Medical School, São Paulo, SP, Brazil
| | - Jorge Hallak
- Department of Surgery, Division of Urology, University of São Paulo Medical School, São Paulo, SP, Brazil
- Department of Pathology, Reproductive Toxicology Unit, University of São Paulo Medical School, São Paulo, SP, Brazil
- Men's Health Study Group, Institute for Advanced Studies, University of São Paulo, São Paulo, SP, Brazil
- Androscience, Science and Innovation Center in Andrology and High-Complex Clinical and Andrology Research Laboratory, São Paulo, SP, Brazil
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Gajski G, Ravlić S, Godschalk R, Collins A, Dusinska M, Brunborg G. Application of the comet assay for the evaluation of DNA damage in mature sperm. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2021; 788:108398. [PMID: 34893163 DOI: 10.1016/j.mrrev.2021.108398] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 10/26/2021] [Accepted: 11/05/2021] [Indexed: 06/14/2023]
Abstract
DNA integrity is considered an important parameter of semen quality and is of significant value as a predictor of male fertility. Currently, there are several methods that can assess sperm DNA integrity. One such assay is the comet assay, or single-cell gel electrophoresis, which is a simple, sensitive, reliable, quick and low-cost technique that is used for measuring DNA strand breaks and repair at the level of individual cells. Although the comet assay is usually performed with somatic cells from different organs, the assay has the ability to detect genotoxicity in germ cells at different stages of spermatogenesis. Since the ability of sperm to remove DNA damage differs between the stages, interpretation of the results is dependent on the cells used. In this paper we give an overview on the use and applications of the comet assay on mature sperm and its ability to detect sperm DNA damage in both animals and humans. Overall, it can be concluded that the presence in sperm of significantly damaged DNA, assessed by the comet assay, is related to male infertility and seems to reduce live births. Although there is some evidence that sperm DNA damage also has a long-term impact on offspring's health, this aspect of DNA damage in sperm is understudied and deserves further attention. In summary, the comet assay can be applied as a useful tool to study effects of genotoxic exposures on sperm DNA integrity in animals and humans.
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Affiliation(s)
- Goran Gajski
- Institute for Medical Research and Occupational Health, Mutagenesis Unit, Zagreb, Croatia.
| | - Sanda Ravlić
- University of Zagreb, Centre for Research and Knowledge Transfer in Biotechnology, Zagreb, Croatia
| | - Roger Godschalk
- Maastricht University, School for Nutrition and Translational Research in Metabolism (NUTRIM), Department of Pharmacology & Toxicology, Maastricht, the Netherlands
| | - Andrew Collins
- University of Oslo, Institute of Basic Medical Sciences, Department of Nutrition, Oslo, Norway
| | - Maria Dusinska
- Norwegian Institute for Air Research (NILU), Department of Environmental Chemistry, Health Effects Laboratory, Kjeller, Norway
| | - Gunnar Brunborg
- Norwegian Institute of Public Health (NIPH), Section of Molecular Toxicology, Department of Environmental Health, Oslo, Norway
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Dave P, Farber N, Vij S. Conventional semen analysis and advanced sperm function tests in diagnosis and management of varicocele. Andrologia 2020; 53:e13629. [PMID: 32369238 DOI: 10.1111/and.13629] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 04/06/2020] [Accepted: 04/10/2020] [Indexed: 12/17/2022] Open
Abstract
Clinical varicoceles are a common cause of male infertility and affect sperm parameters as measured in a conventional semen analysis. Varicocelectomy has been shown in prospective studies to improve semen parameters in men with a clinical varicocele. Clinical varicoceles are also a well-known source of oxidative stress which may affect the quality of spermatozoa. Spermatozoa are particularly susceptible to oxidative stress due to a limited capacity for DNA repair. The susceptibility of spermatozoa to oxidative stress is modulated by a balance between ROS and antioxidants, which can be quantified by various laboratory assays. Varicocelectomy has been consistently shown to reduce both ROS and sperm DNA fragmentation, and various assays should be utilised in the diagnosis and treatment of infertile men with a clinical varicocele.
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Affiliation(s)
- Priya Dave
- Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, USA
| | - Nicholas Farber
- Department of Urology, Cleveland Clinic Foundation, Glickman Urological & Kidney Institute, Cleveland, OH, USA
| | - Sarah Vij
- Department of Urology, Cleveland Clinic Foundation, Glickman Urological & Kidney Institute, Cleveland, OH, USA
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Simon L, Emery B, Carrell DT. Sperm DNA Fragmentation: Consequences for Reproduction. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1166:87-105. [DOI: 10.1007/978-3-030-21664-1_6] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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5
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Simopoulou M, Sfakianoudis K, Antoniou N, Maziotis E, Rapani A, Bakas P, Anifandis G, Kalampokas T, Bolaris S, Pantou A, Pantos K, Koutsilieris M. Making IVF more effective through the evolution of prediction models: is prognosis the missing piece of the puzzle? Syst Biol Reprod Med 2018; 64:305-323. [PMID: 30088950 DOI: 10.1080/19396368.2018.1504347] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Assisted reproductive technology has evolved tremendously since the emergence of in vitro fertilization (IVF). In the course of the recent decade, there have been significant efforts in order to minimize multiple gestations, while improving percentages of singleton pregnancies and offering individualized services in IVF, in line with the trend of personalized medicine. Patients as well as clinicians and the entire IVF team benefit majorly from 'knowing what to expect' from an IVF cycle. Hereby, the question that has emerged is to what extent prognosis could facilitate toward the achievement of the above goal. In the current review, we present prediction models based on patients' characteristics and IVF data, as well as models based on embryo morphology and biomarkers during culture shaping a complication free and cost-effective personalized treatment. The starting point for the implementation of prediction models was initiated by the aspiration of moving toward optimal practice. Thus, prediction models could serve as useful tools that could safely set the expectations involved during this journey guiding and making IVF treatment more effective. The aim and scope of this review is to thoroughly present the evolution and contribution of prediction models toward an efficient IVF treatment. ABBREVIATIONS IVF: In vitro fertilization; ART: assisted reproduction techniques; BMI: body mass index; OHSS: ovarian hyperstimulation syndrome; eSET: elective single embryo transfer; ESHRE: European Society of Human Reproduction and Embryology; mtDNA: mitochondrial DNA; nDNA: nuclear DNA; ICSI: intracytoplasmic sperm injection; MBR: multiple birth rates; LBR: live birth rates; SART: Society for Assisted Reproductive Technology Clinic Outcome Reporting System; AFC: antral follicle count; GnRH: gonadotrophin releasing hormone; FSH: follicle stimulating hormone; LH: luteinizing hormone; AMH: anti-Müllerian hormone; DHEA: dehydroepiandrosterone; PCOS: polycystic ovarian syndrome; NPCOS: non-polycystic ovarian syndrome; CE: cost-effectiveness; CC: clomiphene citrate; ORT: ovarian reserve test; EU: embryo-uterus; DET: double embryo transfer; CES: Cumulative Embryo Score; GES: Graduated Embryo Score; CSS: Combined Scoring System; MSEQ: Mean Score of Embryo Quality; IMC: integrated morphology cleavage; EFNB2: ephrin-B2; CAMK1D: calcium/calmodulin-dependent protein kinase 1D; GSTA4: glutathione S-transferase alpha 4; GSR: glutathione reductase; PGR: progesterone receptor; AMHR2: anti-Müllerian hormone receptor 2; LIF: leukemia inhibitory factor; sHLA-G: soluble human leukocyte antigen G.
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Affiliation(s)
- Mara Simopoulou
- a Department of Physiology , Medical School, National and Kapodistrian University of Athens , Athens , Greece.,b Assisted Conception Unit, 2nd Department of Obstetrics and Gynecology , Aretaieion Hospital, Medical School, National and Kapodistrian University of Athens , Athens , Greece
| | | | - Nikolaos Antoniou
- a Department of Physiology , Medical School, National and Kapodistrian University of Athens , Athens , Greece
| | - Evangelos Maziotis
- a Department of Physiology , Medical School, National and Kapodistrian University of Athens , Athens , Greece
| | - Anna Rapani
- a Department of Physiology , Medical School, National and Kapodistrian University of Athens , Athens , Greece
| | - Panagiotis Bakas
- b Assisted Conception Unit, 2nd Department of Obstetrics and Gynecology , Aretaieion Hospital, Medical School, National and Kapodistrian University of Athens , Athens , Greece
| | - George Anifandis
- d Department of Histology and Embryology, Faculty of Medicine , University of Thessaly , Larissa , Greece
| | - Theodoros Kalampokas
- b Assisted Conception Unit, 2nd Department of Obstetrics and Gynecology , Aretaieion Hospital, Medical School, National and Kapodistrian University of Athens , Athens , Greece
| | - Stamatis Bolaris
- e Department fo Obsterics and Gynaecology , Assisted Conception Unit, General-Maternity District Hospital "Elena Venizelou" , Athens , Greece
| | - Agni Pantou
- c Department of Assisted Conception , Human Reproduction Genesis Athens Clinic , Athens , Greece
| | - Konstantinos Pantos
- c Department of Assisted Conception , Human Reproduction Genesis Athens Clinic , Athens , Greece
| | - Michael Koutsilieris
- a Department of Physiology , Medical School, National and Kapodistrian University of Athens , Athens , Greece
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Bui AD, Sharma R, Henkel R, Agarwal A. Reactive oxygen species impact on sperm DNA and its role in male infertility. Andrologia 2018; 50:e13012. [DOI: 10.1111/and.13012] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2018] [Indexed: 02/07/2023] Open
Affiliation(s)
- A. D. Bui
- American Center for Reproductive Medicine; Cleveland Clinic; Cleveland OH USA
- Ohio University Heritage College of Osteopathic Medicine; Athens OH USA
| | - R. Sharma
- American Center for Reproductive Medicine; Cleveland Clinic; Cleveland OH USA
| | - R. Henkel
- Department of Medical Bioscience; University of the Western Cape; Bellville South Africa
| | - A. Agarwal
- American Center for Reproductive Medicine; Cleveland Clinic; Cleveland OH USA
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Simon L, Emery BR, Carrell DT. Review: Diagnosis and impact of sperm DNA alterations in assisted reproduction. Best Pract Res Clin Obstet Gynaecol 2017; 44:38-56. [DOI: 10.1016/j.bpobgyn.2017.07.003] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/11/2017] [Accepted: 07/24/2017] [Indexed: 01/31/2023]
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8
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Simon L, Zini A, Dyachenko A, Ciampi A, Carrell DT. A systematic review and meta-analysis to determine the effect of sperm DNA damage on in vitro fertilization and intracytoplasmic sperm injection outcome. Asian J Androl 2017; 19:80-90. [PMID: 27345006 PMCID: PMC5227680 DOI: 10.4103/1008-682x.182822] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Sperm DNA damage is prevalent among infertile men and is known to influence natural reproduction. However, the impact of sperm DNA damage on assisted reproduction outcomes remains controversial. Here, we conducted a meta-analysis of studies on sperm DNA damage (assessed by SCSA, TUNEL, SCD, or Comet assay) and clinical pregnancy after IVF and/or ICSI treatment from MEDLINE, EMBASE, and PUBMED database searches for this analysis. We identified 41 articles (with a total of 56 studies) including 16 IVF studies, 24 ICSI studies, and 16 mixed (IVF + ICSI) studies. These studies measured DNA damage (by one of four assays: 23 SCSA, 18 TUNEL, 8 SCD, and 7 Comet) and included a total of 8068 treatment cycles (3734 IVF, 2282 ICSI, and 2052 mixed IVF + ICSI). The combined OR of 1.68 (95% CI: 1.49–1.89; P < 0.0001) indicates that sperm DNA damage affects clinical pregnancy following IVF and/or ICSI treatment. In addition, the combined OR estimates of IVF (16 estimates, OR = 1.65; 95% CI: 1.34–2.04; P < 0.0001), ICSI (24 estimates, OR = 1.31; 95% CI: 1.08–1.59; P = 0.0068), and mixed IVF + ICSI studies (16 estimates, OR = 2.37; 95% CI: 1.89–2.97; P < 0.0001) were also statistically significant. There is sufficient evidence in the existing literature suggesting that sperm DNA damage has a negative effect on clinical pregnancy following IVF and/or ICSI treatment.
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Affiliation(s)
- Luke Simon
- Department of Surgery (Urology), University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Armand Zini
- Division of Urology, Department of Surgery, St. Mary's Hospital Center, St. Mary's Hospital, 3830 Lacombe Avenue, Montreal, Quebec H3T 1M5, Canada
| | - Alina Dyachenko
- Division of Urology, Department of Surgery, St. Mary's Hospital Center, St. Mary's Hospital, 3830 Lacombe Avenue, Montreal, Quebec H3T 1M5, Canada
| | - Antonio Ciampi
- Division of Urology, Department of Surgery, St. Mary's Hospital Center, St. Mary's Hospital, 3830 Lacombe Avenue, Montreal, Quebec H3T 1M5, Canada
| | - Douglas T Carrell
- Department of Surgery (Urology), University of Utah School of Medicine, Salt Lake City, UT, USA.,Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA.,Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City, UT, USA
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9
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Cissen M, Wely MV, Scholten I, Mansell S, Bruin JPD, Mol BW, Braat D, Repping S, Hamer G. Measuring Sperm DNA Fragmentation and Clinical Outcomes of Medically Assisted Reproduction: A Systematic Review and Meta-Analysis. PLoS One 2016; 11:e0165125. [PMID: 27832085 PMCID: PMC5104467 DOI: 10.1371/journal.pone.0165125] [Citation(s) in RCA: 197] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Sperm DNA fragmentation has been associated with reduced fertilization rates, embryo quality, pregnancy rates and increased miscarriage rates. Various methods exist to test sperm DNA fragmentation such as the sperm chromatin structure assay (SCSA), the sperm chromatin dispersion (SCD) test, the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labelling (TUNEL) assay and the single cell gel electrophoresis (Comet) assay. We performed a systematic review and meta-analysis to assess the value of measuring sperm DNA fragmentation in predicting chance of ongoing pregnancy with IVF or ICSI. Out of 658 unique studies, 30 had extractable data and were thus included in the meta-analysis. Overall, the sperm DNA fragmentation tests had a reasonable to good sensitivity. A wide variety of other factors may also affect the IVF/ICSI outcome, reflected by limited to very low specificity. The constructed hierarchical summary receiver operating characteristic (HSROC) curve indicated a fair discriminatory capacity of the TUNEL assay (area under the curve (AUC) of 0.71; 95% CI 0.66 to 0.74) and Comet assay (AUC of 0.73; 95% CI 0.19 to 0.97). The SCSA and the SCD test had poor predictive capacity. Importantly, for the TUNEL assay, SCD test and Comet assay, meta-regression showed no differences in predictive value between IVF and ICSI. For the SCSA meta-regression indicated the predictive values for IVF and ICSI were different. The present review suggests that current sperm DNA fragmentation tests have limited capacity to predict the chance of pregnancy in the context of MAR. Furthermore, sperm DNA fragmentation tests have little or no difference in predictive value between IVF and ICSI. At this moment, there is insufficient evidence to recommend the routine use of sperm DNA fragmentation tests in couples undergoing MAR both for the prediction of pregnancy and for the choice of treatment. Given the significant limitations of the evidence and the methodological weakness and design of the included studies, we do urge for further research on the predictive value of sperm DNA fragmentation for the chance of pregnancy after MAR, also in comparison with other predictors of pregnancy after MAR.
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Affiliation(s)
- Maartje Cissen
- Department of Obstetrics & Gynaecology, Jeroen Bosch Hospital, 's-Hertogenbosch, The Netherlands
| | - Madelon van Wely
- Center for Reproductive Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Irma Scholten
- Center for Reproductive Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Steven Mansell
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Jan Peter de Bruin
- Department of Obstetrics & Gynaecology, Jeroen Bosch Hospital, 's-Hertogenbosch, The Netherlands
| | - Ben Willem Mol
- The Robinson Institute/School of Paediatrics and Reproductive Health, University of Adelaide, Adelaide, Australia
| | - Didi Braat
- Department of Obstetrics and Gynaecology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sjoerd Repping
- Center for Reproductive Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Geert Hamer
- Center for Reproductive Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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INFERTILIDAD MASCULINA Y FRAGMENTACIÓN DEL ADN ESPERMÁTICO: UN PROBLEMA ACTUAL. TIP REVISTA ESPECIALIZADA EN CIENCIAS QUÍMICO-BIOLÓGICAS 2015. [DOI: 10.1016/j.recqb.2015.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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11
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Khaksar Z, Jelodar G, Hematian H, Poorahmadi M. Alterations in gonadal and testicular cells of male fetuses and neonates of diabetic rats. COMPARATIVE CLINICAL PATHOLOGY 2013. [DOI: 10.1007/s00580-012-1537-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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Abstract
As assisted reproductive technology (ART) methods become the mainstream of infertility treatment, it has become even more critical to reassess its safety. Following the results of a study published by the Robinson Institute in the New England Journal of Medicine, the risk of ART, especially intracytoplasmic sperm injection (ICSI), has never been so closely scrutinized. This paper traces the origins and development of ICSI, assesses the risks documented in the literature, and finally interprets the implications of the study for couples contemplating therapy. We support the need for continued vigilance towards ICSI and the importance in investigating male-factor infertility as a prequel to its use.
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13
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Tamburrino L, Marchiani S, Montoya M, Elia Marino F, Natali I, Cambi M, Forti G, Baldi E, Muratori M. Mechanisms and clinical correlates of sperm DNA damage. Asian J Androl 2011; 14:24-31. [PMID: 22138903 DOI: 10.1038/aja.2011.59] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Among the different DNA anomalies that can be present in the male gamete, DNA fragmentation is the most frequent, particularly in infertile subjects. There is now consistent evidence that a sperm containing fragmented DNA can be alive, motile, morphologically normal and able to fertilize an oocyte. There is also evidence that the oocyte is able to repair DNA damage; however, the extent of this repair depends on the type of DNA damage present in the sperm, as well as on the quality of the oocyte. Thus, it is important to understand the possible consequences of sperm DNA fragmentation (SDF) for embryo development, implantation, pregnancy outcome and the health of progeny conceived, both naturally and by assisted reproductive technology (ART). At present, data on the consequences of SDF for reproduction are scarce and, in many ways, inconsistent. The differences in study conclusions might result from the different methods used to detect SDF, the study design and the inclusion criteria. Consequently, it is difficult to decide whether SDF testing should be carried out in fertility assessment and ART. It is clear that there is an urgent need for the standardisation of the methods and for additional clinical studies on the impact of SDF on ART outcomes.
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Affiliation(s)
- Lara Tamburrino
- Department of Clinical Physiopathology, Andrology Unit, University of Florence, Italy
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14
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Abstract
Sperm DNA can be damaged due to a multitude of different noxae, which include disease, and occupational and environmental factors. Depending on the magnitude of the damage, such lesions may be repaired by the oocyte or the embryo. If this is not possible, a permanent damage can be manifested leading to mutations of the male genome. In cases where the oocyte or the embryo does not counter these damages to the male genome in terms of repair or an early abortion, sperm DNA damage and fragmentation can be a cause of numerous diseases including childhood cancer.
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Affiliation(s)
- Ralf R. Henkel
- Department of Medical Biosciences, University of the Western Cape, Bellville, South Africa
| | - Daniel R. Franken
- Department of Obstetrics and Gynaecology, University of Stellenbosch, Tygerberg, South Africa
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Karimi J, Goodarzi MT, Tavilani H, Khodadadi I, Amiri I. Increased receptor for advanced glycation end products in spermatozoa of diabetic men and its association with sperm nuclear DNA fragmentation. Andrologia 2011; 44 Suppl 1:280-6. [PMID: 21919942 DOI: 10.1111/j.1439-0272.2011.01178.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Although the majority of patients with diabetes have disorders in sexual function, associations between diabetes mellitus and sperm function at the molecular level are largely unknown. As receptor for advanced glycation end products plays a key role in many diabetic complications, we hypothesised that it may be involved in sperm nuclear DNA fragmentation. RAGE levels were determined using ELISA and western blot analysis in sperm samples from 32 diabetic and 35 nondiabetic men. Sperm DNA fragmentation was assessed using TUNEL assay. Diabetic men had significantly higher mean levels of RAGE protein (P < 0.001) and DNA fragmentation (P < 0.001) in spermatozoa. Sperm RAGE was directly correlated to sperm DNA fragmentation in diabetic men (r = 0.81, P < 0.001). The high positive correlation between RAGE levels and nuclear DNA fragmentation in spermatozoa of diabetic men suggests a central role of RAGE in disturbances in sexual function of diabetic men.
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Affiliation(s)
- J Karimi
- Department of Biochemistry, Medical School, Hamadan University of Medical Sciences, Hamadan, Iran
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Sperm DNA integrity assays: diagnostic and prognostic challenges and implications in management of infertility. J Assist Reprod Genet 2011; 28:1073-85. [PMID: 21904910 DOI: 10.1007/s10815-011-9631-8] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2011] [Accepted: 08/24/2011] [Indexed: 12/22/2022] Open
Abstract
Sperm is not a simple carrier of paternal genetic information but its role extends clearly beyond fertilization. Integrity of sperm genome is an essential pre-requisite for birth of healthy offspring and evaluation of sperm should entail DNA integrity analysis. DNA integrity analysis is a better diagnostic and prognostic marker of sperm reproductive potential. Conventional semen analysis emphasizes on sperm concentration, viability, motility and morphology and has been proven to be a poor indicator of reproductive potential and pregnancy outcome. To overcome the drawbacks associated with conventional semen analysis more useful fertility tests and molecular biomarkers have been explored. Among the different tests which have evolved for assessing the sperm reproductive potential, tests for sperm DNA quality are most promising. Sperm DNA damage has been closely associated with numerous indicators of reproductive health including fertilization, embryo quality, implantation, spontaneous abortion, congenital malformations and childhood diseases. It therefore has great potential as a prognostic test for both in vitro and in vivo conception. This review presents an updated account of tests that have better diagnostic and prognostic implications in the evaluation of sperm DNA damage. The basic principles, outline of methodology, advantage, disadvantage, clinical significance of each technique and implications of these tests have been discussed. The logistics of each test with respect to available resources and equipment in an andrology laboratory, the feasibility of performing these tests in routine diagnostic workup of infertile men and the opportunities and challenges provided by DNA testing in male fertility determination are also presented.
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17
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Sperm chromatin dispersion test in the assessment of DNA fragmentation and aneuploidy in human spermatozoa. Reprod Biomed Online 2011; 22:428-36. [PMID: 21397561 DOI: 10.1016/j.rbmo.2011.01.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 11/17/2010] [Accepted: 01/27/2011] [Indexed: 01/12/2023]
Abstract
Sperm DNA damage is thought to be increased in men with male factor infertility. Previous studies suggest a correlation between sperm DNA fragmentation and aneuploidy. The sperm chromatin dispersion (SCD) test was modified to produce the Halosperm Kit. The SCD-fluorescent in-situ hybridization (FISH) test allows the simultaneous detection of DNA fragmentation and aneuploidy on the same sperm cell. The objectives of this study were to validate the SCD, SCD-FISH and Halosperm tests for the analysis of sperm DNA fragmentation and compare them to the sperm chromatin structure assay (SCSA). Semen samples from 20 males undergoing IVF/intracytoplasmic sperm injection were processed using FISH, SCD-FISH, SCD and Halosperm, and compared with SCSA results. There was a significant difference between FISH and SCD-FISH results in the detection of aneuploidy (P=0.000) and the level of sperm DNA fragmentation in the samples subjected to SCSA and SCD (P=0.001) or SCSA and SCD-FISH (P=0.001). There was no significant correlation between DNA fragmentation and aneuploidy. If sperm aneuploidy is to be determined, more reliable results will be obtained if FISH is performed rather than SCD-FISH. A lack of validation and unknown clinical significance question the value of DNA fragmentation assays. DNA damage in the male germ line may result in adverse clinical outcomes and the pathophysiology and clinical consequences of sperm DNA damage are being actively researched. Many DNA fragmentation assays such as the Halosperm Kit have been developed recently and are now available at a commercial level. Unfortunately, aimed at vulnerable couples with difficulty conceiving, many of these tests have not been clinically validated. Despite its plausible appeal and fervour of its supporters, the benefits of widespread DNA testing that only achieves the distressing of couples with the knowledge that effectual therapeutic strategies are absent are questionable. Commercially, however, it is no doubt lucrative. Analysis of gametes prior to the initiation of an IVF cycle may improve the quality of embryos transferred. The clinical and scientific community considers it a matter of urgency to translate the basic science behind how a cell prepares for fertilization into routine clinical practice. However, it is equally important, if not more, to allow the science behind such applications to draw level with its practice before its widespread implementation.
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Chioccarelli T, Cacciola G, Altucci L, Lewis SEM, Simon L, Ricci G, Ledent C, Meccariello R, Fasano S, Pierantoni R, Cobellis G. Cannabinoid receptor 1 influences chromatin remodeling in mouse spermatids by affecting content of transition protein 2 mRNA and histone displacement. Endocrinology 2010; 151:5017-29. [PMID: 20810562 DOI: 10.1210/en.2010-0133] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Marijuana smokers and animals treated with Δ9-tetrahydrocannabinol, the principal component of marijuana, show alterations of sperm morphology suggesting a role for cannabinoids in sperm differentiation and/or maturation. Because the cannabinoid receptor 1 (CNR1) activation appears to play a pivotal role in spermiogenesis, the developmental stage where DNA is remodeled, we hypothesized that CNR1 receptors might also influence chromatin quality in sperm. We used Cnr1 null mutant (Cnr1-/-) mice to study the possible role of endocannabinoids on sperm chromatin during spermiogenesis. We demonstrated that CNR1 activation regulated chromatin remodeling of spermatids by either increasing Tnp2 levels or enhancing histone displacement. Comparative analysis of wild-type, Cnr1+/-, and Cnr1-/- animals suggested the possible occurrence of haploinsufficiency for Tnp2 turnover control by CNR1, whereas histone displacement was disrupted to a lesser extent. Furthermore, flow cytometry analysis demonstrated that the genetic loss of Cnr1 decreased sperm chromatin quality and was associated with sperm DNA fragmentation. This damage increased during epididymal transit, from caput to cauda. Collectively, our results show that the expression/activity of CNR1 controls the physiological alterations of DNA packaging during spermiogenesis and epididymal transit. Given the deleterious effects of sperm DNA damage on male fertility, we suggest that the reproductive function of marijuana users may also be impaired by deregulation of the endogenous endocannabinoid system.
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Affiliation(s)
- Teresa Chioccarelli
- Dipartimento di Medicina Sperimentale, Sez. Bottazzi, Seconda Università di Napoli, 80138 Naples, Italy
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Henkel R, Hoogendijk CF, Bouic PJD, Kruger TF. TUNEL assay and SCSA determine different aspects of sperm DNA damage. Andrologia 2010; 42:305-13. [DOI: 10.1111/j.1439-0272.2009.01002.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Simon L, Brunborg G, Stevenson M, Lutton D, McManus J, Lewis SEM. Clinical significance of sperm DNA damage in assisted reproduction outcome. Hum Reprod 2010; 25:1594-608. [DOI: 10.1093/humrep/deq103] [Citation(s) in RCA: 169] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Ramalho-Santos J, Varum S, Amaral S, Mota PC, Sousa AP, Amaral A. Mitochondrial functionality in reproduction: from gonads and gametes to embryos and embryonic stem cells. Hum Reprod Update 2009; 15:553-72. [DOI: 10.1093/humupd/dmp016] [Citation(s) in RCA: 308] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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Male and female factors that influence ICSI outcome in azoospermia or aspermia. Reprod Biomed Online 2009; 18:168-76. [DOI: 10.1016/s1472-6483(10)60252-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Baumgartner A, Cemeli E, Anderson D. The comet assay in male reproductive toxicology. Cell Biol Toxicol 2007; 25:81-98. [PMID: 17972149 DOI: 10.1007/s10565-007-9041-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Accepted: 10/03/2007] [Indexed: 01/23/2023]
Abstract
Due to our lifestyle and the environment we live in, we are constantly confronted with genotoxic or potentially genotoxic compounds. These toxins can cause DNA damage to our cells, leading to an increase in mutations. Sometimes such mutations could give rise to cancer in somatic cells. However, when germ cells are affected, then the damage could also have an effect on the next and successive generations. A rapid, sensitive and reliable method to detect DNA damage and assess the integrity of the genome within single cells is that of the comet or single-cell gel electrophoresis assay. The present communication gives an overview of the use of the comet assay utilising sperm or testicular cells in reproductive toxicology. This includes consideration of damage assessed by protocol modification, cryopreservation vs the use of fresh sperm, viability and statistics. It further focuses on in vivo and in vitro comet assay studies with sperm and a comparison of this assay with other assays measuring germ cell genotoxicity. As most of the de novo structural aberrations occur in sperm and spermatogenesis is functional from puberty to old age, whereas female germ cells are more complicated to obtain, the examination of male germ cells seems to be an easier and logical choice for research and testing in reproductive toxicology. In addition, the importance of such an assay for the paternal impact of genetic damage in offspring is undisputed. As there is a growing interest in the evaluation of genotoxins in male germ cells, the comet assay allows in vitro and in vivo assessments of various environmental and lifestyle genotoxins to be reliably determined.
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Affiliation(s)
- A Baumgartner
- Division of Biomedical Sciences, University of Bradford, Richmond Road, Bradford, West Yorkshire BD7 1DP, UK
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Tarozzi N, Bizzaro D, Flamigni C, Borini A. Clinical relevance of sperm DNA damage in assisted reproduction. Reprod Biomed Online 2007; 14:746-57. [PMID: 17579991 DOI: 10.1016/s1472-6483(10)60678-5] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Many studies have shown how a 'paternal effect' can cause repeated assisted reproduction failures. In particular, with increasing experience of intracytoplasmic sperm injection (ICSI), it became evident that spermatozoa from some patients repeatedly fail to form viable embryos, although they can fertilize the oocyte and trigger early preimplantation development. Many authors have shown how this paternal effect can be traced back to anomalies in sperm chromatin organization: the spermatozoa of subfertile men are characterized by numerical abnormalities in spermatozoal chromosome content, Y chromosome microdeletions, alterations in the epigenetic regulation of paternal genome and non-specific DNA strand breaks. In particular, pathologically increased sperm DNA fragmentation is one of the main paternal-derived causes of repeated assisted reproduction failures in the ICSI era. The intention of this review is to describe nuclear sperm DNA damage, with emphasis on its clinical significance and its relationship with male infertility. Assessment of sperm DNA damage appears to be a potential tool for evaluating semen samples prior to their use in assisted reproduction, helping to select spermatozoa with intact DNA or with the least amount of DNA damage for use in assisted conception.
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Affiliation(s)
- Nicoletta Tarozzi
- Tecnobios Procreazione, Centre for Reproductive Health, Via Dante 15, I-40125 Bologna, Italy
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Li Z, Wang L, Cai J, Huang H. Correlation of sperm DNA damage with IVF and ICSI outcomes: a systematic review and meta-analysis. J Assist Reprod Genet 2006; 23:367-76. [PMID: 17019633 PMCID: PMC3455102 DOI: 10.1007/s10815-006-9066-9] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2006] [Accepted: 08/22/2006] [Indexed: 01/23/2023] Open
Abstract
PURPOSE To assess the effects of sperm DNA damage, as determined by the TUNEL assay and the SCSA respectively, on the outcomes of IVF/ICSI treatment. METHODS A Medline search (from Jan 1978 to Apr 2006) was performed, together with a manual search of the bibliographies of retrieved original papers and review articles. 8 articles met all inclusion/exclusion criteria, of which, 5 used the TUNEL assay and the other 3 used the SCSA. All these articles were included in separate meta-analysis. The meta-analysis was conducted using the RevMan software with fixed-effect model or random-effects model. RESULTS As for articles using the TUNEL assay, the pooled results of IVF outcomes indicated that the clinical pregnancy rate (RR 0.68, 95% CI 0.54 to 0.85, P = 0.006), but not the fertilization rate (RR 0.79, 95% CI 0.54 to 1.16, P = 0.23) decreased significantly for patients with high degree of sperm DNA damage compared with those with low degree of sperm DNA damage. RRs of the ICSI outcomes indicated that there was no significant difference in either fertilization rate (RR 1.03, 95% CI 0.89 to1.18, P = 0.70) or clinical pregnancy rate (RR 0.76, 95% CI 0.55 to 1.04, P = 0.09) between these two groups. As for the SCSA papers, the pooled results showed no significant effects of sperm DNA damage on the clinical pregnancy rate after IVF (RR 0.58, 95% CI 0.25 to 1.31, P = 0.19) or ICSI (RR 1.18, 95% CI 0.81 to 1.74, P = 0.38). CONCLUSION(S) Our meta-analysis indicates that sperm DNA damage, as assessed by the TUNEL assay, significantly decreases only the chance of IVF clinical pregnancy, but not that of either IVF fertilization or ICSI fertilization or ICSI clinical pregnancy. Besides, our results also reveal that sperm DNA damage, when assessed by the SCSA, has no significant effect on the chance of clinical pregnancy after IVF or ICSI treatment.
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Affiliation(s)
- Zhongxiang Li
- Center for Reproductive Medicine, Women’ Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310006 P.R. China
| | - Liquan Wang
- Center for Reproductive Medicine, Women’ Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310006 P.R. China
| | - Jie Cai
- Center for Reproductive Medicine, Women’ Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310006 P.R. China
| | - Hefeng Huang
- Center for Reproductive Medicine, Women’ Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310006 P.R. China
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Abstract
Abstract
Intracytoplasmic sperm injection (ICSI) allows the treatment of virtually every type of male infertility. Unlike in vitro fertilization (IVF), its success does not depend on sperm concentration, motility or morphology and most of the physical barriers to fertilisation are by-passes. Since ICSI does not require strongly motile sperm, its use has now been expanded to incorporate immature sperm from the testes and epididymides. Successful fertilisation, pregnancies and healthy babies have all been reported. However, concerns about the safety of ICSI remain due to its short clinical history and the lack of testing on animal models.
Male fertility potential for assisted reproduction by ICSI cannot be measured by conventional parameters. Sperm DNA integrity is increasingly recognised as a more useful indicator. Studies have shown that sperm with higher levels of DNA damage have lower fertilisation rates after IVF and ICSI. Sperm with DNA damage above a certain threshold are associated with a longer time to conceive in otherwise apparently fertile couples and a higher miscarriage rate. DNA damage has been shown to be associated with impaired embryo cleavage. Our group has shown that sperm DNA from testicular sperm is less fragmented than that from epididymal sperm and suggest its preferred use in ICSI.
In addition to nuclear (n) DNA we also assessed the quality of mitochondrial (mt) DNA from testicular sperm from men with obstructive azoospermia undergoing ICSI. We observed that couples achieving a pregnancy had both less mtDNA deletions and less nDNA fragmentation. We found inverse relationships between pregnancy and sperm mtDNA deletion numbers, size and nDNA fragmentation. No relationships were observed with fertilisation rates. With this knowledge, we designed an algorithm for the prediction of pregnancy based on the quality of sperm nDNA and mtDNA.
Each year 40,000 men have a vasectomy in the UK but every year 2500 request a reversal to begin a second family. For such men, vasectomy reversal has recently been replaced in part by testicular biopsy via fine-needle testicular sperm aspiration (TESA) or percutaneous epididymal sperm aspiration (PESA) performed at an outpatient clinic and subsequently used in ICSI. Since these were previously fertile men it has been assumed that they had ‘fertile’ sperm. However the assited conception success rates of these mens partners has not been assessed until recently. We have shown a significant reduction in the clinical pregnancy rates in the partners of men who had had a vasectomy ≥10yrs previously. There is also evidence to suggest that spermatogenesis is significantly impaired in vasectomised men. Marked decreases in spermatocytes, spermatids and spermatozoa have been observed. We have found this to be associated with concomitant increases in apoptotic markers, such as Fas, FasL and Bax. The quality of the remaining sperm is also compromised. Sperm DNA from vasectomized men shows substantial damage which increases with time after surgery. This new use of ICSI will be discussed.
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Erenpreiss J, Spano M, Erenpreisa J, Bungum M, Giwercman A. Sperm chromatin structure and male fertility: biological and clinical aspects. Asian J Androl 2005; 8:11-29. [PMID: 16372115 DOI: 10.1111/j.1745-7262.2006.00112.x] [Citation(s) in RCA: 204] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Sperm chromatin/DNA integrity is essential for the accurate transmission of paternal genetic information, and normal sperm chromatin structure is important for sperm fertilizing ability. The routine examination of semen, which includes sperm concentration, motility and morphology, does not identify defects in sperm chromatin structure. The origin of sperm DNA damage and a variety of methods for its assessment are described. Evaluation of sperm DNA damage appears to be a useful tool for assessing male fertility potential both in vivo and in vitro. The possible impact of sperm DNA defects on the offspring is also discussed.
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Affiliation(s)
- J Erenpreiss
- University of Lund, Fertility Centre, Malmö University Hospital, Malmö SE 205 02, Sweden.
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Holt WV. Is quality assurance in semen analysis still really necessary? A spermatologist's viewpoint. Hum Reprod 2005; 20:2983-6. [PMID: 16006459 DOI: 10.1093/humrep/dei189] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In a provocative article to this Journal, Anne Jecquier, an eminent andrologist who, more than 20 years ago, was a prime mover in suggesting the need for quality assurance (QA) in andrology laboratories, has now proposed that the QA schemes may no longer be needed. Here I reply to that proposition, largely by agreeing that, since the QA schemes have brought about higher technical standards in laboratories, Anne Jecquier's assertion is possibly true. However, vigilance is still needed in discriminating between unproductive investment of time and energy in the refinement of tests that may offer little information about fertility, and maintaining technical standards such that where necessary they provide the requisite information. Thus, although it may not matter in practice whether a sperm concentration is estimated as 100 or 200 x 10(6)/ml, distinguishing between 25 and 100 x 10(6)/ml would probably influence a clinician's treatment decisions. Anne Jecquier also suggested that sperm function tests have limited predictive value in terms of fertility assessment. While I agree that this is largely true at present, I also argue that these tests are probably not developed to their full potential. I am optimistic that tests to distinguish and quantify the population of fertilization-competent sperm within an ejaculate will eventually become available.
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Affiliation(s)
- W V Holt
- Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK.
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Current World Literature. Curr Opin Obstet Gynecol 2005. [DOI: 10.1097/01.gco.0000169110.00376.bd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Lewis SEM, Aitken RJ. DNA damage to spermatozoa has impacts on fertilization and pregnancy. Cell Tissue Res 2005; 322:33-41. [PMID: 15912407 DOI: 10.1007/s00441-005-1097-5] [Citation(s) in RCA: 309] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2004] [Accepted: 02/09/2005] [Indexed: 10/25/2022]
Abstract
DNA damage in the male germ line has been associated with poor semen quality, low fertilization rates, impaired preimplantation development, increased abortion and an elevated incidence of disease in the offspring, including childhood cancer. The causes of this DNA damage are still uncertain but the major candidates are oxidative stress and aberrant apoptosis. The weight of evidence currently favours the former and, in keeping with this conclusion, positive results have been reported for antioxidant therapy both in vivo and in vitro. Resolving the causes of DNA damage in the male germ line will be essential if we are to prevent the generation of genetically damaged human embryos, particularly in the context of assisted conception therapy.
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Affiliation(s)
- S E M Lewis
- School of Medicine, Obstetrics and Gynaecology, Queen's University, Belfast BT12 6BJ, UK
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