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Agudo-Rios C, Sanchez-Rodriguez A, Idrovo IID, Laborda-Gomariz JÁ, Soler AJ, Teves ME, Roldan ERS. Sperm Chromatin Status and DNA Fragmentation in Mouse Species with Divergent Mating Systems. Int J Mol Sci 2023; 24:15954. [PMID: 37958937 PMCID: PMC10648696 DOI: 10.3390/ijms242115954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/30/2023] [Accepted: 10/31/2023] [Indexed: 11/15/2023] Open
Abstract
Sperm DNA integrity and chromatin status serve as pivotal indicators of sperm quality, given their intricate link to sperm function, embryo development, and overall fertility. Defects in chromatin compaction, which are often associated with compromised protamine content, can lead to damaged DNA strands. In this study, the chromatin status and possible correlation with DNA damage was assessed in males of three mouse species: Mus musculus, M. spretus, and M. spicilegus. We employed various staining methods, including aniline blue, methylene blue (Diff-Quik), toluidine blue, and chromomycin A3, to assess chromatin compaction in cauda epididymal sperm. Samples were also analyzed by the sperm chromatin structure assay (SCSA) to estimate DNA fragmentation (%tDFI, %HDS). Analyses were carried out on freshly collected sperm and cells incubated for 3 h in a HEPES-buffered modified Tyrode's medium simulating conditions of the female reproductive tract. Notably, the analysis of chromatin status yielded minimal abnormal values across all three species employing diverse methodologies. SCSA analyses revealed distinct variations in %tDFI between species. Following sperm incubation, the percentages of sperm stained with methylene blue exhibited differences among the species and were significantly correlated to the DNA fragmentation index. HDS demonstrated correlations with the percentages of sperm stained by aniline blue, methylene blue, and chromomycin A3. Overall, chromatin compaction was high across all species, with limited differences among them. The relationship between chromatin status and DNA integrity appeared to be related to levels of sperm competition among species.
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Affiliation(s)
- Clara Agudo-Rios
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), 28006 Madrid, Spain
| | - Ana Sanchez-Rodriguez
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), 28006 Madrid, Spain
| | - Ingrid I. D. Idrovo
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), 28006 Madrid, Spain
| | | | - Ana J. Soler
- SaBio IREC (CSIC-UCLM-JCCM), ETSIAM, Campus Universitario, 02071 Albacete, Spain
| | - Maria E. Teves
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Eduardo R. S. Roldan
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (CSIC), 28006 Madrid, Spain
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2
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Agudo-Rios C, Rogers A, King I, Bhagat V, Nguyen LMT, Córdova-Fletes C, Krapf D, Strauss JF, Arévalo L, Merges GE, Schorle H, Roldan ERS, Teves ME. SPAG17 mediates nuclear translocation of protamines during spermiogenesis. Front Cell Dev Biol 2023; 11:1125096. [PMID: 37766963 PMCID: PMC10520709 DOI: 10.3389/fcell.2023.1125096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 08/21/2023] [Indexed: 09/29/2023] Open
Abstract
Protamines (PRM1 and PRM2) are small, arginine-rich, nuclear proteins that replace histones in the final stages of spermiogenesis, ensuring chromatin compaction and nuclear remodeling. Defects in protamination lead to increased DNA fragmentation and reduced male fertility. Since efficient sperm production requires the translocation of protamines from the cytoplasm to the nucleus, we investigated whether SPAG17, a protein crucial for intracellular protein trafficking during spermiogenesis, participates in protamine transport. Initially, we assessed the protein-protein interaction between SPAG17 and protamines using proximity ligation assays, revealing a significant interaction originating in the cytoplasm and persisting within the nucleus. Subsequently, immunoprecipitation and mass spectrometry (IP/MS) assays validated this initial observation. Sperm and spermatids from Spag17 knockout mice exhibited abnormal protamination, as revealed by chromomycin A3 staining, suggesting defects in protamine content. However, no differences were observed in the expression of Prm1 and Prm2 mRNA or in protein levels between testes of wild-type and Spag17 knockout mice. Conversely, immunofluorescence studies conducted on isolated mouse spermatids unveiled reduced nuclear/cytoplasm ratios of protamines in Spag17 knockout spermatids compared to wild-type controls, implying transport defects of protamines into the spermatid nucleus. In alignment with these findings, in vitro experiments involving somatic cells, including mouse embryonic fibroblasts, exhibited compromised nuclear translocation of PRM1 and PRM2 in the absence of SPAG17. Collectively, our results present compelling evidence that SPAG17 facilitates the transport of protamines from the cytoplasm to the nucleus.
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Affiliation(s)
- Clara Agudo-Rios
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond, VA, United States
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
| | - Amber Rogers
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond, VA, United States
| | - Isaiah King
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond, VA, United States
| | - Virali Bhagat
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond, VA, United States
| | - Le My Tu Nguyen
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond, VA, United States
| | - Carlos Córdova-Fletes
- Departamento de Bioquímica y Medicina Molecular, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey, Mexico
| | - Diego Krapf
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, CO, United States
| | - Jerome F. Strauss
- Department of Obstetrics and Gynecology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Lena Arévalo
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, Bonn, Germany
| | - Gina Esther Merges
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, Bonn, Germany
| | - Hubert Schorle
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, Bonn, Germany
| | - Eduardo R. S. Roldan
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
| | - Maria Eugenia Teves
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond, VA, United States
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Potgieter S, Eddy C, Badrinath A, Chukrallah L, Lo T, Mohanty G, Visconti PE, Snyder EM. ADAD1 is required for normal translation of nuclear pore and transport protein transcripts in spermatids of Mus musculus†. Biol Reprod 2023; 109:340-355. [PMID: 37399121 PMCID: PMC10502568 DOI: 10.1093/biolre/ioad069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 03/23/2023] [Accepted: 06/29/2023] [Indexed: 07/05/2023] Open
Abstract
ADAD1 is a testis-specific RNA-binding protein expressed in post-meiotic spermatids whose loss leads to defective sperm and male infertility. However, the drivers of the Adad1 phenotype remain unclear. Morphological and functional analysis of Adad1 mutant sperm showed defective DNA compaction, abnormal head shaping, and reduced motility. Mutant testes demonstrated minimal transcriptome changes; however, ribosome association of many transcripts was reduced, suggesting ADAD1 may be required for their translational activation. Further, immunofluorescence of proteins encoded by select transcripts showed delayed protein accumulation. Additional analyses demonstrated impaired subcellular localization of multiple proteins, suggesting protein transport is also abnormal in Adad1 mutants. To clarify the mechanism giving rise to this, the manchette, a protein transport microtubule network, and the LINC (linker of nucleoskeleton and cytoskeleton) complex, which connects the manchette to the nuclear lamin, were assessed across spermatid development. Proteins of both displayed delayed translation and/or localization in mutant spermatids implicating ADAD1 in their regulation, even in the absence of altered ribosome association. Finally, ADAD1's impact on the NPC (nuclear pore complex), a regulator of both the manchette and the LINC complex, was examined. Reduced ribosome association of NPC encoding transcripts and reduced NPC protein abundance along with abnormal localization in Adad1 mutants confirmed ADAD1's impact on translation is required for a NPC in post-meiotic germ cells. Together, these studies lead to a model whereby ADAD1's influence on nuclear transport leads to deregulation of the LINC complex and the manchette, ultimately generating the range of physiological defects observed in the Adad1 phenotype.
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Affiliation(s)
- Sarah Potgieter
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Christopher Eddy
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Aditi Badrinath
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Lauren Chukrallah
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Toby Lo
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Gayatri Mohanty
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA, USA
| | - Pablo E Visconti
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA, USA
| | - Elizabeth M Snyder
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
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4
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Bollwein H, Malama E. Review: Evaluation of bull fertility. Functional and molecular approaches. Animal 2023; 17 Suppl 1:100795. [PMID: 37567681 DOI: 10.1016/j.animal.2023.100795] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 08/13/2023] Open
Abstract
With the term "assisted reproduction technologies" in modern cattle farming, one could imply the collection of techniques that aim at the optimal use of bovine gametes to produce animals of high genetic value in a time- and cost-efficient manner. The accurate characterisation of sperm quality plays a critical role for the efficiency of several assisted reproduction-related procedures, such as sperm processing, in vitro embryo production and artificial insemination. Bull fertility is ultimately a collective projection of the ability of a series of ejaculates to endure sperm processing stress, and achieve fertilisation of the oocyte and production of a viable and well-developing embryo. In this concept, the assessment of sperm functional and molecular characteristics is key to bull fertility diagnostics and prognostics. Among others, functional features linked to sperm plasma membrane, acrosome and DNA integrity are usually assessed as a measure of the ability of sperm to express the phenotypes that will allow them to maintain their homeostasis and orchestrate-in a strict temporal manner-the course of events that will enable the delivery of their genetic content to the oocyte upon fertilisation. Nevertheless, measures of sperm functionality are not always adequate indicators of bull fertility. Nowadays, advancements in the field of molecular biology have facilitated the profiling of several biomolecules in male gametes. The molecular profiling of bovine sperm offers a deeper insight into the mechanisms underlying sperm physiology and, thus, can reveal novel candidate markers for bull fertility prognosis. In this review, the importance of three organelles (the nucleus, the plasma membrane and the acrosome) for the characterisation of sperm fertilising capacity and bull fertility is discussed at functional and molecular levels. In particular, information about sperm head morphometry, chromatin structure, viability as well as the ability of sperm to capacitate and undergo the acrosome reaction are presented in relation to the cryotolerance of male gametes and bull fertility. Finally, major spermatozoal coding and non-coding RNAs, and proteins that are involved in the above-mentioned aspects of sperm functionality are also summarised.
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Affiliation(s)
- H Bollwein
- Clinic of Reproductive Medicine, Department for Farm Animals, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
| | - E Malama
- Clinic of Reproductive Medicine, Department for Farm Animals, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland
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5
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Bernal B, Behnamifar A, Álvarez-Rodríguez C, Toledano-Díaz A, Castaño C, Velázquez R, Gil MG, Gutiérrez-Adán A, Woelders H, Blesbois E, Santiago-Moreno J. Transit along the vas deferens results in a high percentage of filiform spermatozoa with compacted chromatin in the rooster ( Gallus domesticus). Reprod Fertil Dev 2022; 34:699-712. [PMID: 35366958 DOI: 10.1071/rd21209] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 02/28/2022] [Indexed: 11/23/2022] Open
Abstract
The present work aimed to evaluate the chromatin compaction of rooster spermatozoa along the male reproductive tract, and to study the vas deferens lining cells, potentially involved in sperm maturation. Chromomycin A3 (CMA3) was used to determine the chromatin compaction of spermatozoa from testis (T), proximal (including epididymis, V1), intermediate (V2) and distal (V3) vas deferens, and ejaculate (E). Six Birchen Leonesa roosters were used. E was obtained in vivo by dorso-ventral massage. V1, V2 and V3 sperm were obtained post mortem (six pairs of vasa deferentia), by flushing. T was obtained by washing the testes, cut in halves. The fixed cells were stained with CMA3 and propidium iodide for flow cytometry assessment. Results showed higher (P P P.
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Affiliation(s)
- B Bernal
- Department of Animal Breeding, INIA-CSIC, Madrid, Spain
| | - A Behnamifar
- Department of Poultry Science, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran
| | | | | | - C Castaño
- Department of Animal Reproduction, INIA-CSIC, Madrid, Spain
| | - R Velázquez
- Department of Animal Reproduction, INIA-CSIC, Madrid, Spain
| | - M G Gil
- Department of Animal Breeding, INIA-CSIC, Madrid, Spain
| | | | - Henri Woelders
- Department of Animal Breeding and Genomics, Wageningen University and Research, Wageningen, Netherlands
| | - E Blesbois
- PRC, CNRS, IFCE, INRAE, Université de Tours, Nouzilly, France
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Ogle RA, Netherton J, Schneider E, Velkov T, Zhang H, Cole N, Hetherington L, Villaverde AISB, Baker MA. Nuclear heterogeneity is prevalent in high-quality fractionated human sperm cells typically used for assisted conception. Hum Reprod 2021; 36:2073-2082. [PMID: 34097020 DOI: 10.1093/humrep/deab134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 04/07/2021] [Indexed: 11/14/2022] Open
Abstract
STUDY QUESTION What is the nuclear heterogeneity of high-density purified human spermatozoa typically used for IVF purposes. SUMMARY ANSWER The data show that while density gradient separation has improved the overall sperm population, there is still a large degree of nuclear heterogeneity within these cells. WHAT IS KNOWN ALREADY Chromomycin A3 (CMA3) is an important DNA binding fluorochrome for the assessment of male-factor fertility. It is typically used to predict IVF outcomes on entire sperm ejaculates with very high receiver operating characteristic. Here we used CMA3 to characterise typical populations of human spermatozoa that would be used for IVF purposes after density gradient separation. STUDY DESIGN, SIZE, DURATION We compared the intensity of CMA3 binding within high-dense sperm populations obtained from men. Binding heterogeneity was confirmed through fluorescence microscopy and FACS analysis independently. We also looked at CMA3 staining directly with head morphology in this sperm population. Finally, we looked at electron micrographs of nuclear heterogeneity (vacuoles, chromatin compaction) of spermatozoa following density gradient sorting of CMA3-stained cells. PARTICIPANTS/MATERIALS, SETTING, METHODS We used sperm donors who had fathered one or more children. Semen was collected after 2 days abstinence and purified over Percoll gradients. Only the high-quality spermatozoa, the same used for assisted conception, were then used. Cells were stained with CMA3 and sorted using FACS. Following this, electron micrographs were used to assess nuclear heterogeneity of CMA3-dependent sorted spermatozoa. MAIN RESULTS AND THE ROLE OF CHANCE CMA3 staining occurs within morphologically normal as well as abnormal spermatozoa. High-intensity CMA3-stained sperm possessed large vacuoles that were not seen in the low-CMA3 population. In addition, the high-CMA3 stained cells possess higher amounts of nuclear granulation. LIMITATIONS, REASONS FOR CAUTION The present study only describes the issues within the chromatin of these cells and does not suggest an alternate selection technique. WIDER IMPLICATIONS OF THE FINDINGS CMA3 is one of the better reported prognostic assays in predicting pregnancy outcomes, especially in cases where the male is at fault. However, it is clear that even in fractionated populations of human spermatozoa, there are sperm cells that are morphologically normal yet possess high levels of CMA3 staining and chromatin granulation. The implication of this is that the embryologist, whom selects on the basis of sperm morphology, may choose a cell with poor chromatin, which may lead to poor embryo outcomes. STUDY FUNDING/COMPETING INTEREST(S) The project was funded by the National Health and Medical Research council, APP1118943. The authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- R A Ogle
- Department of Biological Science, University of Newcastle, Callaghan, NSW, Australia
| | - J Netherton
- Department of Biological Science, University of Newcastle, Callaghan, NSW, Australia
| | - E Schneider
- Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, VIC, Australia
| | - T Velkov
- Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, VIC, Australia
| | - H Zhang
- Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, VIC, Australia
| | - N Cole
- Department of Biological Science, University of Newcastle, Callaghan, NSW, Australia
| | - L Hetherington
- Department of Biological Science, University of Newcastle, Callaghan, NSW, Australia
| | | | - M A Baker
- Department of Biological Science, University of Newcastle, Callaghan, NSW, Australia
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Angrimani DSR, Bicudo LC, Llamas Luceño N, Rui BR, Silva MF, Losano JDA, Leemans B, Van Soom A, Vannucchi CI. Does finasteride treatment for benign prostatic hyperplasia influence sperm DNA integrity in dogs? Basic Clin Androl 2020; 30:9. [PMID: 32695403 PMCID: PMC7364779 DOI: 10.1186/s12610-020-00108-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 06/30/2020] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Benign prostatic hyperplasia (BPH) is one of the most common reproductive disorders in both male dogs and men. Finasteride, a synthetic inhibitor of the enzyme 5α-reductase, is widely used as medical treatment. Although sperm can be affected by both BPH and finasteride treatment, the direct influence on DNA integrity remains unclear. Thus, the aim of this study was to verify the direct effect of BPH and/or finasteride treatment on DNA integrity of dog spermatozoa. A 2 × 2 factorial experiment was designed with 20 male dogs assigned to 4 experimental groups: BPH Group (n = 5), BPH-Finasteride Group (n = 5), Non-BPH Finasteride-Treated Group (n = 5) and Non-BPH Untreated Group (n = 5). Sperm evaluation was performed monthly for 60 days after the start of finasteride therapy or BPH diagnosis (D0, D30 and D60). Sperm DNA integrity was analyzed through fragmentation susceptibility (toluidine blue staining and Sperm Chromatic Structure Assay - SCSA), direct evaluation of DNA fragmentation (Sperm Chromatin Dispersion Assay - SCDA) and sperm protamination (chromomycin A3). RESULTS Sperm DNA integrity was not affected by finasteride treatment. However, BPH dogs had higher susceptibility to sperm DNA acid denaturation (SCSA) compared to dogs not presenting BPH, as well as lower percentage of sperm with DNA integrity (toluidine blue staining). CONCLUSION In conclusion, benign prostatic hyperplasia causes post-testicular sperm DNA damage, albeit finasteride treatment itself does not directly influence sperm DNA integrity.
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Affiliation(s)
- Daniel S. R. Angrimani
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Orlando Marques de Paiva, 87, São Paulo, 05508-270 Brazil
| | - Luana C. Bicudo
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Orlando Marques de Paiva, 87, São Paulo, 05508-270 Brazil
| | - Nuria Llamas Luceño
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - Bruno R. Rui
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Orlando Marques de Paiva, 87, São Paulo, 05508-270 Brazil
| | - Matheus F. Silva
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Orlando Marques de Paiva, 87, São Paulo, 05508-270 Brazil
| | - João D. A. Losano
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Orlando Marques de Paiva, 87, São Paulo, 05508-270 Brazil
| | - Bart Leemans
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - Ann Van Soom
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - Camila I. Vannucchi
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Orlando Marques de Paiva, 87, São Paulo, 05508-270 Brazil
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Michl TD, Hibbs B, Hyde L, Postma A, Tran DTT, Zhalgasbaikyzy A, Vasilev K, Meagher L, Griesser HJ, Locock KES. Bacterial membrane permeability of antimicrobial polymethacrylates: Evidence for a complex mechanism from super-resolution fluorescence imaging. Acta Biomater 2020; 108:168-177. [PMID: 32179195 DOI: 10.1016/j.actbio.2020.03.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 03/03/2020] [Accepted: 03/04/2020] [Indexed: 12/31/2022]
Abstract
Amphiphilic polymers bearing cationic moieties are an emerging alternative to traditional antibiotics given their broad-spectrum activity and low susceptibility to the development of resistance. To date, however, much remains unclear regarding their mechanism of action. Using functional assays (ATP leakage, cell viability, DNA binding) and super-high resolution structured illumination microscopy (OMX-SR) of fluorescently tagged polymers, we present evidence for a complex mechanism, involving membrane permeation as well as cellular uptake, interaction with intracellular targets and possible complexation with bacterial DNA. STATEMENT OF SIGNIFICANCE: This manuscript details the first study to systematically and directly investigate the mechanism of action of antimicrobial polymers, using super-resolution fluorescence imaging as well as functional assays. While many in the field cite membrane permeation as the sole mechanism underlying the activity of such polymers, we present evidence for multimodal actions including high cellular uptake and interaction with intracellular targets. It is also the first report to show competitive binding of antimicrobial polymers with bacterial DNA in a dose-dependent manner.
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Affiliation(s)
- Thomas D Michl
- School of Engineering, University of South Australia, Mawson Lakes Blvd, Mawson Lakes, SA 5095, Australia
| | - Ben Hibbs
- Materials Characterisation and Fabrication Platform, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Lauren Hyde
- Materials Characterisation and Fabrication Platform, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Almar Postma
- CSIRO Manufacturing, Research Way, Clayton, VIC 3168, Australia
| | - Dung Thuy Thi Tran
- School of Engineering, University of South Australia, Mawson Lakes Blvd, Mawson Lakes, SA 5095, Australia
| | - Aigerim Zhalgasbaikyzy
- School of Engineering, University of South Australia, Mawson Lakes Blvd, Mawson Lakes, SA 5095, Australia
| | - Krasimir Vasilev
- School of Engineering, University of South Australia, Mawson Lakes Blvd, Mawson Lakes, SA 5095, Australia
| | - Laurence Meagher
- Department of Materials Science and Engineering, Monash University, Clayton, VIC 3168, Australia
| | - Hans J Griesser
- Future Industries Institute, University of South Australia, Mawson Lakes Blvd, Mawson Lakes, SA 5095, Australia
| | - Katherine E S Locock
- CSIRO Manufacturing, Research Way, Clayton, VIC 3168, Australia; Department of Chemical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia.
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9
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Hamilton TRS, Simões R, Mendes CM, Goissis MD, Nakajima E, Martins EAL, Visintin JA, Assumpção MEOA. Detection of protamine 2 in bovine spermatozoa and testicles. Andrology 2019; 7:373-381. [PMID: 30920782 DOI: 10.1111/andr.12610] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/14/2019] [Accepted: 02/25/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Sperm DNA integrity is crucial for transmission of genetic information to future generations and DNA damage can occur during chromatin packaging. Chromatin packaging involves the replacement of somatic nucleosomal histones by nuclear proteins called protamines. Protamine 1 (PRM1) is transcribed and translated in spermatids of all mammals; however, protamine 2 (PRM2) is transcribed in low levels in spermatids and it is not yet described in bull mature spermatozoa. OBJECTIVES The aim of this study was to assess gene and protein expression of PRM2 and corroborate gene and protein expression of PRM1 in bull spermatozoa and testis. MATERIALS AND METHODS For this purpose, absolute q-RT-PCR was performed to calculate the number of copies of PRM1 and PRM2 mRNAs in bovine epididymal spermatozoa and testicular tissue. Western blot and mass spectrometry were performed to identify PRM1 and PRM2 in samples of bovine epididymal spermatozoa. Samples of bovine testicular tissue were collected to identify PRM1 and PRM2 by immunohistochemistry. RESULTS We evaluated that the number of PRM1 mRNA copies was about hundred times higher than PRM2 mRNA copies in sperm and testicular samples (p < 0.0001). In addition, we estimated the PRM1: PRM2 ratio based on mRNA number of copies. In spermatozoa, the ratio was 1: 0.014, and in testicle, the ratio was 1: 0.009. We also evaluated the immunolocalization for PRM1 and PRM2 in bovine testis, and both proteins were detected in spermatids. Western blot and mass spectrometry in bovine epididymal spermatozoa confirmed these results. CONCLUSION Our work identifies, for the first time, PRM2 in bovine epididymal spermatozoa and in testis. Further studies are still needed to understand the role of PRM2 on the chromatin of the spermatozoa and to verify how possible changes in PRM2 levels may influence the bull fertility.
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Affiliation(s)
- T R S Hamilton
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
| | - R Simões
- Center for Natural and Human Sciences, Federal University of ABC, Santo André, Brazil
| | - C M Mendes
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
| | - M D Goissis
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
| | - E Nakajima
- Process Development Laboratory, Inovation Division, Butantan Institute, São Paulo, Brazil
| | - E A L Martins
- Process Development Laboratory, Inovation Division, Butantan Institute, São Paulo, Brazil
| | - J A Visintin
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
| | - M E O A Assumpção
- Department of Animal Reproduction, School of Veterinary Medicine, University of São Paulo, Avenida Professor Doutor Orlando Marques de Paiva, Sao Paulo, Brazil
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10
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Souza ET, Silva CV, Travençolo BAN, Alves BG, Beletti ME. Sperm chromatin alterations in fertile and subfertile bulls. Reprod Biol 2018; 18:177-181. [DOI: 10.1016/j.repbio.2018.04.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 03/17/2018] [Accepted: 04/16/2018] [Indexed: 01/17/2023]
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11
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Effect of bovine sperm chromatin integrity evaluated using three different methods on in vitro fertility. Theriogenology 2017; 107:142-148. [PMID: 29154161 DOI: 10.1016/j.theriogenology.2017.11.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 11/03/2017] [Accepted: 11/03/2017] [Indexed: 01/17/2023]
Abstract
In vitro fertility potential of individual bulls is still relatively uncharacterized. Classical sperm analysis does not include the evaluation of all sperm characteristics and thus, some cell compartments could be neglected. In humans, sperm DNA integrity has already proven to have major influence in embryo development and assisted reproduction techniques successfully. In bovine, some studies already correlated chromatin integrity with field fertility. However, none of those have attempted to relate DNA assessment approaches such as chromatin deficiency (CMA3), chromatin stability (SCSA; AO+) and DNA fragmentation (COMET assay) to predict in vitro bull fertility. To this purpose, we selected bulls with high and low in vitro fertility (n = 6/group), based on embryo development rate (blastocyst/cleavage rate). We then performed CMA3, SCSA test and COMET assay to verify if the difference of in vitro fertility may be related to DNA alterations evaluated by these assays. For the three tests performed, our results showed only differences in the percentage of cells with chromatin deficiency (CMA3+; high: 0.19 ± 0.03 vs low: 0.04 ± 0.04; p = 0.03). No difference for chromatin stability and any of COMET assay categories (grade I to grade IV) was observed between high and low in vitro fertility bulls. A positive correlation between AO + cells and grade IV cells was found. Despite the difference between groups in CMA3 analysis, our results suggest that protamine deficiency in bovine spermatozoa may not have a strong biological impact to explain the difference of in vitro fertility between the bulls used in this study.
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Takeda N, Yoshinaga K, Furushima K, Takamune K, Li Z, Abe SI, Aizawa SI, Yamamura KI. Viable offspring obtained from Prm1-deficient sperm in mice. Sci Rep 2016; 6:27409. [PMID: 27250771 PMCID: PMC4890041 DOI: 10.1038/srep27409] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/18/2016] [Indexed: 12/14/2022] Open
Abstract
Protamines are expressed in the spermatid nucleus and allow denser packaging of DNA compared with histones. Disruption of the coding sequence of one allele of either protamine 1 (Prm1) or Prm2 results in failure to produce offspring, although sperm with disrupted Prm1 or Prm2 alleles are produced. Here, we produced Prm1-deficient female chimeric mice carrying Prm1-deficient oocytes. These mice successfully produced Prm1(+/-) male mice. Healthy Prm1(+/-) offspring were then produced by transferring blastocysts obtained via in vitro fertilization using zona-free oocytes and sperm from Prm1(+/-) mice. This result suggests that sperm lacking Prm1 can generate offspring despite being abnormally shaped and having destabilised DNA, decondensed chromatin and a reduction in mitochondrial membrane potential. Nevertheless, these mice showed little derangement of expression profiles.
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Affiliation(s)
- Naoki Takeda
- Division of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, 2-2-1 Honjo, Kumamoto 860-0811, Japan
| | - Kazuya Yoshinaga
- Department of Anatomy, Graduate School of Health Sciences, Kumamoto University, 4-24-1 Kuhonji, Kumamoto 862-0975, Japan
| | - Kenryo Furushima
- Department of Molecular Cell Biology and Molecular Medicine, Institute of Advanced Medicine, Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Japan
| | - Kazufumi Takamune
- Department of Biological Sciences, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan
| | - Zhenghua Li
- Department of Histology and Embryology, Harbin Medical University, Harbin 150081, China
| | - Shin-Ichi Abe
- Kumamoto Health Science University, 325 Izumi-machi, Kita-ku, Kumamoto 861-5598, Japan
| | - Shin-Ichi Aizawa
- Center for Developmental Biology, RIKEN Kobe, 2-2-3 Minatojima Minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Ken-Ichi Yamamura
- Yamamura Project Laboratory, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto 860-0811, Japan
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13
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Zhu WJ, Li J. A simple sperm nuclear vacuole assay with propidium iodide. Andrologia 2014; 47:779-85. [DOI: 10.1111/and.12328] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2014] [Indexed: 11/29/2022] Open
Affiliation(s)
- W.-J. Zhu
- Department of Developmental and Regenerative Biology; College of Life Science and Technology; Jinan University; Guangzhou China
| | - J. Li
- Department of Pathophysiology; Medical College; Jinan University; Guangzhou China
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Utsuno H, Miyamoto T, Oka K, Shiozawa T. Morphological alterations in protamine-deficient spermatozoa. Hum Reprod 2014; 29:2374-81. [DOI: 10.1093/humrep/deu225] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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15
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O'Flaherty C. Iatrogenic genetic damage of spermatozoa. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 791:117-35. [PMID: 23955676 DOI: 10.1007/978-1-4614-7783-9_8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Various factors that negatively influence male fertility can affect sperm morphology and physiology. Many studies on humans and animals suggest that both radiation and chemotherapy alter the sperm chromatin, inducing significant damage to sperm DNA, and decrease the level of protamination, thereby altering DNA compaction. Spermatozoa from cancer survivors are affected by chemotherapy even years after the end of treatment. We are exposed to various toxicants present in the environment (e.g., products of air pollution, pesticides, and plasticizers) whose impact on human male reproduction has not yet been established.This chapter aims to update our knowledge on how the sperm chromatin structure is modified by external agents and to describe the different strategies available to better study this complex structure in infertile men.
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Affiliation(s)
- Cristian O'Flaherty
- Division of Urology, Department of Surgery, McGill University and the Research Institute- McGill University Health Centre, Royal Victoria Hospital, room H6.46, 687 Avenue des Pins Ouest, Montréal, Québec, H3A 1A1, Canada,
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Smith TB, De Iuliis GN, Lord T, Aitken RJ. The senescence-accelerated mouse prone 8 as a model for oxidative stress and impaired DNA repair in the male germ line. Reproduction 2013; 146:253-62. [DOI: 10.1530/rep-13-0186] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The discovery of a truncated base excision repair pathway in human spermatozoa mediated by OGG1 has raised questions regarding the effect of mutations in critical DNA repair genes on the integrity of the paternal genome. The senescence-accelerated mouse prone 8 (SAMP8) is a mouse model containing a suite of naturally occurring mutations resulting in an accelerated senescence phenotype largely mediated by oxidative stress, which is further enhanced by a mutation in theOgg1gene, greatly reducing the ability of the enzyme to excise 8-hydroxy,2′-deoxyguanosine (8OHdG) adducts. An analysis of the reproductive phenotype of the SAMP8 males revealed a high level of DNA damage in caudal epididymal spermatozoa as measured by the alkaline Comet assay. Furthermore, these lesions were confirmed to be oxidative in nature, as demonstrated by significant increases in 8OHdG adduct formation in the SAMP8 testicular tissue (P<0.05) as well as in mature spermatozoa (P<0.001) relative to a control strain (SAMR1). Despite this high level of oxidative DNA damage in spermatozoa, reactive oxygen species generation was not elevated and motility of spermatozoa was found to be similar to that for the control strain with the exception of progressive motility, which exhibited a slight but significant decline with advancing age (P<0.05). When challenged with Fenton reagents (H2O2and Fe2+), the SAMP8 spermatozoa demonstrated a highly increased susceptibility to formation of 8OHdG adducts compared with the controls (P<0.001). These data highlight the role of oxidative stress and OGG1-dependent base excision repair mechanisms in defining the genetic integrity of mammalian spermatozoa.
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Liu T, Huang Y, Liu J, Zhao Y, Jiang L, Huang Q, Cheng W, Guo L. MicroRNA-122 influences the development of sperm abnormalities from human induced pluripotent stem cells by regulating TNP2 expression. Stem Cells Dev 2013; 22:1839-50. [PMID: 23327642 DOI: 10.1089/scd.2012.0653] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Sperm abnormalities are one of the main factors responsible for male infertility; however, their pathogenesis remains unclear. The role of microRNAs in the development of sperm abnormalities in infertile men has not yet been investigated. Here, we used human induced pluripotent stem cells to investigate the influence of miR-122 expression on the differentiation of these cells into spermatozoa-like cells in vitro. After induction, mutant miR-122-transfected cells formed spermatozoa-like cells. Flow cytometry of DNA content revealed a significant increase in the haploid cell population in spermatozoa-like cells derived from mutant miR-122-transfected cells as compared to those derived from miR-122-transfected cells. During induction, TNP2 and protamine mRNA and protein levels were significantly higher in mutant miR-122-transfected cells than in miR-122-transfected cells. High-throughput isobaric tags for relative and absolute quantification were used to identify and quantify the different protein expression levels in miR-122- and mutant miR-122-transfected cells. Among all the proteins analyzed, the expression of lipoproteins, for example, APOB and APOA1, showed the most significant difference between the two groups. This study illustrates that miR-122 expression is associated with abnormal sperm development. MiR-122 may influence spermatozoa-like cells by suppressing TNP2 expression and inhibiting the expression of proteins associated with sperm development.
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Affiliation(s)
- Te Liu
- International Peace Maternity and Child Health Hospital, Shanghai Jiaotong University, Shanghai, China.
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Zandemami M, Qujeq D, Akhondi MM, Kamali K, Raygani M, Lakpour N, Shiraz ES, Sadeghi MR. Correlation of CMA3 Staining with Sperm Quality and Protamine Deficiency. Lab Med 2012. [DOI: 10.1309/lmb42f9qxykfljng] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Rahman MB, Vandaele L, Rijsselaere T, Maes D, Hoogewijs M, Frijters A, Noordman J, Granados A, Dernelle E, Shamsuddin M, Parrish JJ, Van Soom A. Scrotal insulation and its relationship to abnormal morphology, chromatin protamination and nuclear shape of spermatozoa in Holstein-Friesian and Belgian Blue bulls. Theriogenology 2011; 76:1246-57. [PMID: 21777969 DOI: 10.1016/j.theriogenology.2011.05.031] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 05/12/2011] [Accepted: 05/13/2011] [Indexed: 11/30/2022]
Abstract
The objectives of this study were to identify the stages of spermatogenesis susceptible to elevated testicular temperature in terms of sperm motility, viability, morphology, chromatin protamination and nuclear shape. The latter two valuable parameters are not included in routine semen analysis. Scrotal insulation (SI) was applied for 48 h in 2 Holstein-Friesian (HF) and 2 Belgian Blue (BB) bulls and semen was collected at 7 d intervals along with semen collection of a non-insulated bull of each breed. Semen samples were frozen and assigned to 4 groups: period 1 (preinsulation) = -7 d and 0 d, where 0 d = initiation of SI after semen collection; period 2 = 7 d (sperm presumed in the epididymis during SI); period 3 = 14 d to 42 d (cells presumed at spermiogenesis and meiosis stages during SI); period 4 = 49 d to 63 d (cells presumed at spermatocytogenesis stage during SI). The percentages of progressively motile and viable spermatozoa as assessed by computer-assisted sperm analysis (CASA) and fluorescence microscopy, respectively were decreased whereas abnormal sperm heads, nuclear vacuoles and tail defects were increased at period 3 (P < 0.05) compared to period 1, 2 or 4 in SI bulls of both HF and BB breeds. Protamine deficient spermatozoa as observed by chromomycin A(3) (CMA(3)) staining were more present (P < 0.05) at period 2 and 3 in both breeds compared to period 1 or 4. Sperm nuclear shape as determined by Fourier harmonic amplitude (FHA) was most affected by heat stress during period 3 (P < 0.01) and a higher response was observed in BB bulls than HF bulls. In conclusion, sperm cells at the spermiogenic and meiotic stages of development are more susceptible to heat stress. The lack of chromatin protamination is the most pertinent result of heat stress, together with subtle changes in sperm head shape, which can be detected by FHA but not by conventional semen analysis.
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Affiliation(s)
- Mohammad Bozlur Rahman
- Department of Reproduction, Obstetrics and Herd Health, Ghent University, Ghent, Belgium.
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Franco Jr JG, Mauri AL, Petersen CG, Massaro FC, Silva LFI, Felipe V, Cavagna M, Pontes A, Baruffi RLR, Oliveira JBA, Vagnini LD. Large nuclear vacuoles are indicative of abnormal chromatin packaging in human spermatozoa. ACTA ACUST UNITED AC 2011; 35:46-51. [DOI: 10.1111/j.1365-2605.2011.01154.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Oliva R, de Mateo S. Medical Implications of Sperm Nuclear Quality. EPIGENETICS AND HUMAN REPRODUCTION 2011. [DOI: 10.1007/978-3-642-14773-9_3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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22
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De Iuliis GN, Thomson LK, Mitchell LA, Finnie JM, Koppers AJ, Hedges A, Nixon B, Aitken RJ. DNA damage in human spermatozoa is highly correlated with the efficiency of chromatin remodeling and the formation of 8-hydroxy-2'-deoxyguanosine, a marker of oxidative stress. Biol Reprod 2009; 81:517-24. [PMID: 19494251 DOI: 10.1095/biolreprod.109.076836] [Citation(s) in RCA: 292] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
DNA damage in human spermatozoa has been associated with a range of adverse clinical outcomes, including infertility, abortion, and disease in the offspring. We have advanced a two-step hypothesis to explain this damage involving impaired chromatin remodeling during spermiogenesis followed by a free radical attack to induce DNA strand breakage. The objective of the present study was to test this hypothesis by determining whether impaired chromatin protamination is correlated with oxidative base damage and DNA fragmentation in human spermatozoa. DNA fragmentation, chromatin protamination, mitochondrial membrane potential, and formation of the oxidative base adduct, 8-hydroxy-2'-deoxyguanosine (8OHdG), were monitored by flow cytometry/fluorescence microscopy. Impairment of DNA protamination during late spermatogenesis was highly correlated (P < 0.001) with DNA damage in human spermatozoa. The disruption of chromatin remodeling also was associated with a significant elevation in the levels of 8OHdG (P < 0.001), and the latter was itself highly correlated with DNA fragmentation (P < 0.001). The significance of oxidative stress in 8OHdG formation was demonstrated experimentally using H2O2/Fe2+ and by the correlation observed between this base adduct and superoxide generation (P < 0.001). That 8OHdG formation was inversely associated with mitochondrial membrane potential (P < 0.001) suggested a possible role for these organelles in the creation of oxidative stress. These results clearly highlight the importance of oxidative stress in the induction of sperm DNA damage and carry significant implications for the clinical management of this condition.
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Affiliation(s)
- Geoffry N De Iuliis
- ARC Centre of Excellence in Biotechnology and Development and Hunter Medical Research Institute, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales 2308, Australia
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Nasr-Esfahani MH, Abasi H, Razavi S, Ashrafi S, Tavalaee M. Varicocelectomy: semen parameters and protamine deficiency. ACTA ACUST UNITED AC 2009; 32:115-22. [DOI: 10.1111/j.1365-2605.2007.00822.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Simões R, Feitosa WB, Mendes CM, Marques MG, Nicacio AC, de Barros FRO, Visintin JA, Assumpção M. Use of chromomycin A3 staining in bovine sperm cells for detection of protamine deficiency. Biotech Histochem 2009; 84:79-83. [DOI: 10.1080/10520290902843595] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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25
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Tarozzi N, Nadalini M, Stronati A, Bizzaro D, Dal Prato L, Coticchio G, Borini A. Anomalies in sperm chromatin packaging: implications for assisted reproduction techniques. Reprod Biomed Online 2009; 18:486-95. [DOI: 10.1016/s1472-6483(10)60124-1] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Angelopoulou R, Plastira K, Msaouel P. Spermatozoal sensitive biomarkers to defective protaminosis and fragmented DNA. Reprod Biol Endocrinol 2007; 5:36. [PMID: 17760963 PMCID: PMC2000879 DOI: 10.1186/1477-7827-5-36] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2007] [Accepted: 08/30/2007] [Indexed: 11/24/2022] Open
Abstract
Human sperm DNA damage may have adverse effects on reproductive outcome. Infertile men possess substantially more spermatozoa with damaged DNA compared to fertile donors. Although the extent of this abnormality is closely related to sperm function, the underlying etiology of ensuing male infertility is still largely controversial. Both intra-testicular and post-testicular events have been postulated and different mechanisms have been proposed to explain the presence of damaged DNA in human spermatozoa. Three among them, i.e. abnormal chromatin packaging, oxidative stress and apoptosis, are the most studied and discussed in the present review. Furthermore, results from numerous investigations are presented, including our own findings on these pathological conditions, as well as the techniques applied for their evaluation. The crucial points of each methodology on the successful detection of DNA damage and their validity on the appraisal of infertile patients are also discussed. Along with the conventional parameters examined in the standard semen analysis, evaluation of damaged sperm DNA seems to complement the investigation of factors affecting male fertility and may prove an efficient diagnostic tool in the prediction of pregnancy outcome.
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Affiliation(s)
- Roxani Angelopoulou
- Experimental Embryology Unit, Department of Histology and Embryology, Medical School, National and Kapodistrian University of Athens, Greece
| | - Konstantina Plastira
- Experimental Embryology Unit, Department of Histology and Embryology, Medical School, National and Kapodistrian University of Athens, Greece
| | - Pavlos Msaouel
- Experimental Embryology Unit, Department of Histology and Embryology, Medical School, National and Kapodistrian University of Athens, Greece
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Codrington AM, Hales BF, Robaire B. Exposure of male rats to cyclophosphamide alters the chromatin structure and basic proteome in spermatozoa. Hum Reprod 2007; 22:1431-42. [PMID: 17303633 DOI: 10.1093/humrep/dem002] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The formation of mature sperm involves the expression of numerous proteins during spermiogenesis and the replacement of histones with protamines to package the genome. Exposure to cyclophosphamide (CPA), an anticancer alkylating agent, during spermiogenesis may disrupt chromatin condensation with adverse consequences to the offspring. METHODS Adult male rats were given CPA in one of two schedules: (i) subchronic, 4 days - day 1 (100 mg kg(-1)) and days 2-4 (50 mg kg(-1) per day) or (ii) chronic - daily (6.0 mg kg(-1) per day). Animals were euthanized on days 14, 21 or 28. RESULTS The effects of CPA on epididymal sperm chromatin structure were germ-cell-phase specific; mid-spermiogenic spermatids were most sensitive. The acridine orange DNA denaturation assay showed significant increases in susceptibility to denaturation (P < 0.01). Chromatin packaging assessment revealed 1,4-dithiothreitol-dependent chromomycin A3 DNA binding and less condensed, protamine-deficient sperm; the total thiol (P < 0.001) and protamine contents (P < 0.01), measured using monobromobimane and the HUP1N protamine 1 antibody, respectively, were reduced. The sperm basic proteome was also altered; proteins that were identified are involved in events during spermiogenesis and fertilization. CONCLUSIONS Paternal exposure to CPA alters sperm chromatin structure, as well as the composition of sperm head basic proteins. We speculate that these changes underlie effects on fertilization and embryo development.
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Affiliation(s)
- A M Codrington
- Department of Pharmacology, McGill University, Montreal, Quebec, Canada
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Nasr-Esfahani MH, Razavi S, Mardani M, Shirazi R, Javanmardi S. Effects of failed oocyte activation and sperm protamine deficiency on fertilization post-ICSI. Reprod Biomed Online 2007; 14:422-9. [PMID: 17425821 DOI: 10.1016/s1472-6483(10)60888-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Sperm premature chromosomal condensation (PCC) has been associated with failed fertilization. Previous studies suggest that protamine deficiency or failed oocyte activation may make spermatozoa prone to PCC. However, it is not clear which of these two factors has a more profound effect on fertilization failure. In order to distinguish between these two phenomena, oocytes that failed to fertilize after intracytoplasmic sperm injection (ICSI) were artificially activated and the association between protamine deficiency and PCC was evaluated in the remaining oocytes that failed to fertilize. The results of this study reveal that after artificial activation, fertilization rate post-ICSI increased from 59.95 to 87.7% and PCC spermatozoa appeared to be present in over 50% of the remaining oocytes that failed to fertilize. The percentage of sperm PCC was significantly higher in protamine deficient samples, thus suggesting that after failed oocyte activation, sperm PCC induced by protamine deficiency may be considered as an alternative cause of failed fertilization post-ICSI. Furthermore, the results of this study did not show any correlation between pronuclei size asynchrony and protamine deficiency.
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Zubkova EV, Robaire B. Effects of ageing on spermatozoal chromatin and its sensitivity to in vivo and in vitro oxidative challenge in the Brown Norway rat. Hum Reprod 2006; 21:2901-10. [PMID: 16982656 DOI: 10.1093/humrep/del193] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The goals of our study were to examine chromatin packaging and integrity in spermatozoa taken from the caput and cauda epididymides of young (4-month-old) and old (21-month-old) Brown Norway rats and to assess whether spermatozoal sensitivity to oxidative treatments is altered with age. METHODS Oxidative treatments consisted of (i) in vivo oxidative challenge by systemic administration of the glutathione-depleting drug l-buthionine-[S,R]-sulphoximine (BSO) and (ii) in vitro oxidative challenge by incubating collected spermatozoa with hydrogen peroxide (H(2)O(2)). Chromatin parameters assessed included quantification of thiols, nuclear chromomycin A3 (CMA3) penetration, DNA breaks by TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling (TUNEL) and ease of DNA dissociation by acridine orange (AO) staining. RESULTS In spermatozoa from older rats, we found decreases in thiols, CMA3 penetration and the percentage of cells that undergo DNA dissociation. Administration of BSO had oxidizing effects on the thiol groups. It also decreased CMA3 penetration and DNA dissociation and increased TUNEL staining. Furthermore, BSO treatment sensitized cauda epididymidis spermatozoa, from older animals, to H(2)O(2). CONCLUSIONS Overall, we show that spermatozoa from older rats have altered chromatin packaging and integrity and that spermatozoa from the cauda epididymidis are more responsive to combined in vivo and in vitro oxidative challenge than spermatozoa from young rats.
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Affiliation(s)
- Ekaterina V Zubkova
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada
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Abstract
Protamines are the major nuclear sperm proteins. The human sperm nucleus contains two types of protamine: protamine 1 (P1) encoded by a single-copy gene and the family of protamine 2 (P2) proteins (P2, P3 and P4), all also encoded by a single gene that is transcribed and translated into a precursor protein. The protamines were discovered more than a century ago, but their function is not yet fully understood. In fact, different hypotheses have been proposed: condensation of the sperm nucleus into a compact hydrodynamic shape, protection of the genetic message delivered by the spermatozoa, involvement in the processes maintaining the integrity and repair of DNA during or after the nucleohistone-nucleoprotamine transition and involvement in the epigenetic imprinting of the spermatozoa. Protamines are also one of the most variable proteins found in nature, with data supporting a positive Darwinian selection. Changes in the expression of P1 and P2 protamines have been found to be associated with infertility in man. Mutations in the protamine genes have also been found in some infertile patients. Transgenic mice defective in the expression of protamines also present several structural defects in the sperm nucleus and have variable degrees of infertility. There is also evidence that altered levels of protamines may result in an increased susceptibility to injury in the spermatozoan DNA causing infertility or poor outcomes in assisted reproduction. The present work reviews the articles published to date on the relationship between protamines and infertility.
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Affiliation(s)
- Rafael Oliva
- Human Genetics Laboratory, Genetics Unit, Department of Ciències Fisiològiques I, Faculty of Medicine, University of Barcelona and Hospital Clínic, IDIBAPS, Casanova 143, 08036 Barcelona, Spain.
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Zubkova EV, Wade M, Robaire B. Changes in spermatozoal chromatin packaging and susceptibility to oxidative challenge during aging. Fertil Steril 2005; 84 Suppl 2:1191-8. [PMID: 16210011 DOI: 10.1016/j.fertnstert.2005.04.044] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2005] [Revised: 04/28/2005] [Accepted: 04/28/2005] [Indexed: 10/25/2022]
Abstract
OBJECTIVE Our goal was to test the hypothesis that spermatozoal chromatin packaging changes with age and that aging affects the susceptibility of spermatozoal DNA to oxidative damage. DESIGN Laboratory study. SETTING Academic facility. PATIENT(S) Young (4 months) and old (21 months) Brown Norway rats. INTERVENTION(S) Spermatozoa were collected from the cauda epididymidis and were incubated in saline or H2O2. MAIN OUTCOME MEASUREMENT(S) Thiols levels, chromatin condensation, DNA susceptibility to acid-induced DNA denaturation, and DNA damage were evaluated using monobromobimane, chromomycin A3 (CMA3), acridine orange, and polymerase chain reaction, respectively. RESULT(S) Spermatozoa from old rats had 25% fewer disulfides but similar levels of free thiols as compared with young. The CMA3 staining was decreased by 13% with age. Levels of chromatin denaturation and DNA damage were similar in control groups. After exposure to oxidant, free thiols became oxidized by about 20% irrespective of age, but CMA3 staining changed little. The acridine orange assay, however, showed a trend for greater chromatin denaturation in spermatozoa from old rats after oxidant treatment. Furthermore, the DNA from spermatozoa of old rats was significantly more susceptible to developing DNA breaks and modification after oxidative challenge. CONCLUSION(S) Spermatozoal chromatin packaging changes with aging and vulnerability to oxidative damage increases.
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Affiliation(s)
- Ekaterina V Zubkova
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada
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Bianchi P, De Agostini A, Fournier J, Guidetti C, Tarozzi N, Bizzaro D, Manicardi G. Human cervical mucus can act in vitro as a selective barrier against spermatozoa carrying fragmented DNA and chromatin structural abnormalities. J Assist Reprod Genet 2005; 21:97-102. [PMID: 15270207 PMCID: PMC3455610 DOI: 10.1023/b:jarg.0000029492.54243.3c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE We have carried out experiments to determine if human cervical mucus can act as an in vitro selective barrier against spermatozoa morphologically normal that carry genetic structural abnormalities. METHODS Sperm chromatin abnormalities have been evaluated by Chromomycin A3 and "endogenous" nick translation. RESULTS The data obtained have shown that spermatozoa possessing higher levels of DNA protamination are more proficient in crossing the cervical mucus barrier. Moreover, the levels of positivity to endogenous nick translation treatment was practically zero in such spermatozoa. CONCLUSIONS We suggest that sperm penetration of cervical mucus could be used to select sperm preparations free of fragmented DNA or chromatin structural abnormalities for assisted reproduction.
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Affiliation(s)
- P.G. Bianchi
- Clinic of Sterility, Department of Obstetrics and Gynaecology, University Hospital of Geneva, Geneva, Switzerland
| | - A. De Agostini
- Clinic of Sterility, Department of Obstetrics and Gynaecology, University Hospital of Geneva, Geneva, Switzerland
| | - J. Fournier
- Clinic of Sterility, Department of Obstetrics and Gynaecology, University Hospital of Geneva, Geneva, Switzerland
| | - C. Guidetti
- Dipartimento di Scienze Agrarie, Università di Modena e Reggio Emilia, Reggio Emilia, Italy
| | - N. Tarozzi
- Clinic of Sterility, Department of Obstetrics and Gynaecology, University Hospital of Geneva, Geneva, Switzerland
| | - D. Bizzaro
- Istituto di Biologia e Genetica, Università Politecnica delle Marche, Ancona, Italy
| | - G.C. Manicardi
- Dipartimento di Scienze Agrarie, Università di Modena e Reggio Emilia, Reggio Emilia, Italy
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Perreault SD, Aitken RJ, Baker HWG, Evenson DP, Huszar G, Irvine DS, Morris ID, Morris RA, Robbins WA, Sakkas D, Spano M, Wyrobek AJ. Integrating new tests of sperm genetic integrity into semen analysis: breakout group discussion. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2004; 518:253-68. [PMID: 12817694 DOI: 10.1007/978-1-4419-9190-4_23] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Sally D Perreault
- U.S. EPA, ORD, NHEERL, Reproductive Toxicology Division, Research Triangle Park, NC 27711, USA.
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Sakkas D, Manicardi GC, Bizzaro D. Sperm nuclear DNA damage in the human. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2004; 518:73-84. [PMID: 12817678 DOI: 10.1007/978-1-4419-9190-4_7] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Denny Sakkas
- Department of Obstetrics and Gynaecology, Yale University School of Medicine, Connecticut 06520, USA.
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Wiethoff CM, Gill ML, Koe GS, Koe JG, Middaugh CR. A fluorescence study of the structure and accessibility of plasmid DNA condensed with cationic gene delivery vehicles. J Pharm Sci 2003; 92:1272-85. [PMID: 12761816 DOI: 10.1002/jps.10391] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The cationic lipids 1,2-dioleoyl-3-trimethylammonium-propane and dimethyldioctadecylammonium bromide, with or without the helper lipids 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine or cholesterol, and the cationic polymer polyethyleneimine, were compared for their ability to displace fluorescent dyes from DNA. Differences in displacement of the intercalating dyes ethidium bromide and ethidium homodimer correlate with their relative affinities with DNA, with the extent of ethidium homodimer displacement significantly less. Differences in ethidium homodimer and ethidium bromide displacement as a function of the ratio of polycation to DNA and the charge density of the polycation suggest a greater sensitivity of the former to topological changes in condensed DNA. Marked differences in the ability of these cationic delivery systems to displace the minor groove binding dyes 4',6-diamidino-2-phenylindole and Hoechst 33258 upon interaction with DNA are also apparent, with the majority of Hoechst 33258 remaining bound to DNA. Changes in the spectral properties of Hoechst 33258 were further used to characterize polycation-induced changes in solvent accessibility of the DNA minor groove. Taken together, these studies demonstrate differences in the interaction of various cationic lipids and polyethyleneimine in terms of regional displacement of dyes, polycation-induced structural changes in DNA, as well as polycation-mediated changes in solvent accessibility of the minor groove. The relevance of these studies to current models of the structure and assembly of polycation/DNA complexes are discussed.
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Affiliation(s)
- Christopher M Wiethoff
- Department of Pharmaceutical Chemistry, The University of Kansas, 2095 Constant Avenue, Lawrence, Kansas 66047, USA
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Tomlinson MJ, Moffatt O, Manicardi GC, Bizzaro D, Afnan M, Sakkas D. Interrelationships between seminal parameters and sperm nuclear DNA damage before and after density gradient centrifugation: implications for assisted conception. Hum Reprod 2001; 16:2160-5. [PMID: 11574509 DOI: 10.1093/humrep/16.10.2160] [Citation(s) in RCA: 201] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND With an increase in the use of assisted reproduction technologies the requirements of the diagnostic semen analysis are constantly changing. METHODS Spermatozoa from patients undergoing IVF were analysed by examining the conventional semen parameters and DNA/chromatin integrity, using in-situ nick translation (NT) and the Chromomycin A(3) fluorochrome, which indirectly demonstrates a decreased presence of protamine. Samples were examined before and after preparation using discontinuous density gradient centrifugation. RESULTS Density gradient centrifugation enriched samples by improving the percentage of morphologically normal forms by 138% and sperm nuclear integrity by 450%. Sperm nuclear integrity as assessed by in-situ nick translation (NT) demonstrated a very clear relationship with sperm concentration, motility and morphology. Morphology correlated with fertilization rates of patients undergoing IVF, while NT values of the spermatozoa post-preparation were significantly lower in pregnant patients. CONCLUSIONS We have demonstrated that along with the classical semen parameters, the assessment of nuclear integrity improves the characterization of the semen sample and may be used as a tool for allocating patients to specific assisted reproduction treatments.
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Affiliation(s)
- M J Tomlinson
- Assisted Conception Unit, Birmingham Women's Hospital, Birmingham, UK
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Esterhuizen AD, Franken DR, Lourens JG, Prinsloo E, van Rooyen LH. Sperm chromatin packaging as an indicator of in-vitro fertilization rates. Hum Reprod 2000; 15:657-61. [PMID: 10686215 DOI: 10.1093/humrep/15.3.657] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The development of a sequential diagnostic schedule for patients consulting for infertility disturbances would be an ideal method of approach for clinicians in the absence of an aetiological or pathophysiological diagnosis. Since sperm morphology recorded by strict criteria has often been correlated with fertilization failure, the present study aimed to evaluate the relationship between normal morphology as well as in-vitro fertilization (IVF) rates, with chromatin staining among fertile and subfertile men. Two semen smears were prepared from each specimen obtained from 72 men to record normal morphology and chromatin packaging as recorded by chromomycin A(3) (CMA(3)) staining. Following the semen analyses, the 72 men were divided into the two morphological groups, namely <4% and >4% normal forms. Significantly different percentages of CMA(3) staining (mean +/- SE) were recorded between the two morphological groups, namely 65.9% +/- 3.5 and 44.5% +/- 1.7 (P +/- 0.001). A highly negative significant correlation existed between percentage of normal morphology as recorded by strict criteria and CMA(3) staining. A highly significant and positive correlation was recorded for normal morphology and IVF rates (r +/- 0.45, P +/- 0.0001). A significant negative correlation (r +/- -0.51, P +/- 0.0001) existed between CMA(3) values and IVF rates. The discriminating power of nuclear maturity, as recorded by CMA(3) staining, to identify abnormal morphology values and poor IVF rates was calculated with receiver operator characteristic (ROC) analyses. The areas under the ROC curves were 0.86 for sperm morphology and 0. 74 for IVF rates. The calculated threshold values for CMA(3) staining to distinguish between morphology groups were 48 and 50% for IVF. Chromatin packaging assessment is a valuable addition to the sequential diagnostic programme in an assisted reproductive arena.
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Affiliation(s)
- A D Esterhuizen
- Andrology Laboratory, du Buisson and partners, Pretoria, South Africa
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Manicardi GC, Tombacco A, Bizzaro D, Bianchi U, Bianchi PG, Sakkas D. DNA strand breaks in ejaculated human spermatozoa: comparison of susceptibility to the nick translation and terminal transferase assays. THE HISTOCHEMICAL JOURNAL 1998; 30:33-9. [PMID: 9539205 DOI: 10.1023/a:1003214529185] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The nick translation and terminal transferase assays have been compared to test their relative efficiency in detecting DNA breakage in ejaculated human spermatozoa. The results have been correlated with the percentage of chromomycin A3 positive sperm, a fluorochrome that is indicative of the protamination state of sperm. Examination of the ejaculated sperm of 30 subjects revealed that the percentage of positivity to the nick translation and terminal transferase assays did not differ, even when using different fixatives. It is concluded that the inability of the two assays to distinguish the type of DNA damage, as is possible in somatic nuclei, is most probably linked to the unique nature of sperm chromatin. It is proposed that the presence of the damaged DNA may be the remnants of an imperfect spermiogenesis, probably related to an inadequate protamine deposition. This is supported by the strong correlation between the presence of DNA damage and underprotamination as evidenced by chromomycin A3.
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Affiliation(s)
- G C Manicardi
- Department of Animal Biology, University of Modena, Italy
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