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Lai TCT, Roychoudhury S, Cho CL. Oxidative Stress and Varicocele-Associated Male Infertility. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1358:205-235. [PMID: 35641872 DOI: 10.1007/978-3-030-89340-8_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Despite being regarded as one of the most common causes of male subfertility, the pathophysiology of varicocele remains largely unknown. Recently, oxidative stress (OS) is proposed to be the mediator in how varicocele may negatively impact fertility. The imbalance of reactive oxygen species (ROS) and seminal antioxidants results in damage to sperm DNA and lipid membrane. There is evidence demonstrating higher OS level in men with varicocele which is also positively correlated with clinical grading of varicocele. Moreover, a number of studies have revealed the negative correlation between OS and conventional semen parameters. Furthermore, various interventions have shown their potential in alleviating OS in men with varicocele-associated infertility. Although direct evidence on improving pregnancy rate is not available at the moment, varicocelectomy has demonstrated promising results in relieving OS. Oral antioxidants represent another option with a favourable safety profile. The supplement can be used alone or as adjunct to varicocelectomy. However, most of the studies are hampered by heterogenous dose regime and high-level evidence is lacking.
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Affiliation(s)
- Terence Chun-Ting Lai
- Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | | | - Chak-Lam Cho
- S. H. Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, Hong Kong.
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2
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Mahdavinezhad F, Farmani AR, Pakniat H, Taghavi S, Gharaei R, Valipour J, Amidi F. COVID-19 and varicocele: the possible overlap factors and the common therapeutic approaches. Am J Reprod Immunol 2021; 87:e13518. [PMID: 34967487 DOI: 10.1111/aji.13518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 12/02/2021] [Accepted: 12/27/2021] [Indexed: 12/15/2022] Open
Abstract
Varicocele is recognized as one of the main attributable causes of male infertility which can affect spermatogenesis by various pathophysiological mechanisms. Recent studies have identified oxidative stress and reduction in antioxidant, hyperthermia, hypoxia, hormonal dysfunction, and inflammatory conditions as major factors in the pathophysiology of varicocele, all of which have known direct associations with the coronavirus disease 2019 (COVID-19) and can significantly increase the risk of detrimental COVID-19-related outcomes. Emerging data have shown an association between COVID-19 and inflammation, overproduction of cytokine, and other pathophysiological processes. The present review, summarizes the current understanding of the pathophysiology of varicocele and investigates the potential correlation between the severity of COVID-19 and the varicocele disease. In addition, various possible treatments which can be effective in both diseases were examined. Despite numerous challenges associated with the prevalence of COVID-19 in healthcare systems in infected countries, special attention should be given to maintaining a high level of care for complex patients with a pre-existing disease such as varicocele and providing appropriate practical advice for optimal control of the COVID-19 disease. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Forough Mahdavinezhad
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Reza Farmani
- Department of Tissue Engineering, Faculty of Advanced Technologies, Tehran University of Medical Sciences, Tehran, Iran.,Tissue Engineering Department, School of Advanced Technologies in Medicine, Fasa University of Medical Sciences, Fasa, Iran
| | - Hamideh Pakniat
- Department of Obstetrics and Gynecology, School of Medicine, Qazvin University of Medical Sciences, Qazvin, Iran
| | - Saeed Taghavi
- Iran Polymer and Petrochemical Institute, Tehran, Iran
| | - Roghaye Gharaei
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Jamal Valipour
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Fardin Amidi
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Department of Infertility, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
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Sanei-Ataabadi N, Mowla SJ, Nasr-Esfahani MH. Transcript Isoforms of SLC7A11-AS1 Are Associated With Varicocele-Related Male Infertility. Front Genet 2020; 11:1015. [PMID: 33024440 PMCID: PMC7516207 DOI: 10.3389/fgene.2020.01015] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 08/10/2020] [Indexed: 12/13/2022] Open
Abstract
Oxidative stress is one of the crucial mediators of varicocele-related male infertility. Recently, roles of long noncoding RNAs (lncRNAs) in oxidative stress have begun to emerge, however, little is known about their role in male infertility. The aim of this study was to determine the role of lncRNA SLC7A11-AS1 in varicocele-related male infertility. Through a high-throughput bioinformatics investigation, we predicted that lncRNA SLC7A11-AS1 might be involved in this type of infertility. The reactive oxygen species (ROS) levels and expression levels of SLC7A11-AS1 isoforms were evaluated in ejaculated spermatozoa of 25 infertile men with varicocele and 17 fertile individuals as control. Isoform 6 of SLC7A11-AS1 that showed a significant elevation in infertile men with varicocele relative to the fertile group was overexpressed in testicular-derived carcinoma cell lines (NT2 and NCCIT) followed by assessment of ROS, glutathione (GSH), lipid peroxidation, and cell viability. Overexpression of SLC7A11-AS1 isoform 6 in NT2 and NCCIT cell lines resulted in a significant downregulation of SLC7A11 gene expression, which consequently decreased GSH levels and concomitantly increased ROS levels and enhanced lipid peroxidation, which jeopardized cell survival and promoted cell death. Our finding revealed a potential role of oxidative-related lncRNAs in the pathophysiology of male infertility associated with varicocele.
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Affiliation(s)
- Nafiseh Sanei-Ataabadi
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Seyed Javad Mowla
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mohammad Hossein Nasr-Esfahani
- Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, Academic Center for Education, Culture and Research (ACECR), Isfahan, Iran.,Isfahan Fertility and Infertility Center, Isfahan, Iran
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Ata-abadi NS, Mowla SJ, Aboutalebi F, Dormiani K, Kiani-Esfahani A, Tavalaee M, Nasr-Esfahani MH. Hypoxia-related long noncoding RNAs are associated with varicocele-related male infertility. PLoS One 2020; 15:e0232357. [PMID: 32353040 PMCID: PMC7192471 DOI: 10.1371/journal.pone.0232357] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 04/13/2020] [Indexed: 12/19/2022] Open
Abstract
One of the main molecular causes that contributes to varicocele-related male infertility is excess production of reactive oxygen species (ROS). It is believed that hypoxia is an important stimulator of ROS in this condition. Recently, the significant roles of long non-coding RNAs (lncRNAs) in hypoxia response have emerged. Despite the investigation of hypoxia, there is scant information about the role of hypoxia-responding lncRNAs in varicocele-related male infertility. In the present study, we deduced eight hypoxia-responding lncRNAs based on high-throughput RNA sequencing data from two Gene Expression Omnibus (GEO) datasets. We used qRT-PCR to assess the expression levels of some of these lncRNAs in 42 ejaculated spermatozoa samples from 25 infertile men with varicocele and 17 fertile men as controls. We identified significant increases in expression levels of hypoxia-related lncRNAs, MIR210HG and MLLT4-AS1 in ejaculated spermatozoa of infertile men with varicocele. These lncRNAs also showed significant positive correlations with ROS levels and meaningful negative correlations with sperm parameters (count and motility). Besides, in silico studies identified several hypoxia response elements (HREs) within selected lncRNAs promoters. Delineation of hypoxia-related lncRNAs in varicocele-related infertility provides a valuable insight into male infertility.
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Affiliation(s)
- Nafiseh Sanei Ata-abadi
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Seyed Javad Mowla
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
- * E-mail: (SJM); (MHN-E)
| | - Fatemeh Aboutalebi
- Department of Molecular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Kianoush Dormiani
- Department of Molecular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Abbas Kiani-Esfahani
- Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Marziyeh Tavalaee
- Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Mohammad Hossein Nasr-Esfahani
- Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
- Isfahan Fertility and Infertility Center, Isfahan, Iran
- * E-mail: (SJM); (MHN-E)
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Zhu SM, Rao T, Yang X, Ning JZ, Yu WM, Ruan Y, Yuan R, Li CL, Jiang K, Hu W, Li HY, Cheng F. Autophagy may play an important role in varicocele. Mol Med Rep 2017; 16:5471-5479. [PMID: 28849201 PMCID: PMC5647093 DOI: 10.3892/mmr.2017.7253] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 08/04/2017] [Indexed: 12/25/2022] Open
Abstract
The present study aimed to determine the expression of autophagy and investigate whether the hypoxia-inducible factor 1α (HIF-1α)/BCL2 interacting protein (BNIP3)/Beclin-1 autophagy signaling pathway serves an important role in activating autophagy in varicocele (VC) rat testes cells. Furthermore, the current study aimed to explain the possible association between autophagy and apoptosis. A total of 48 adult male Sprague Dawley rats were divided into group A (control), group B (VC 15-day), group C (VC 30-day) and group D (VC 45-day), with 12 rats in each group. The rats in group A did not receive any interventions, and in groups B, C, and D the VC model was established simultaneously. At 0, 15, 30, and 45 days, an orchidectomy on the left testes was performed in groups A-D, each on its respective day. Transmission electron microscopy was used to investigate the expression of autophagy. Compared with groups A and B, it was demonstrated that the expression of autophagy in groups C, and D was significantly increased. Hematoxylin and eosin staining revealed that as the rats survived VC longer, the testicular tissue damage became more serious. Furthermore, the Johnson score revealed that VC impaired the spermeiogenesis function of the male rats. Additionally, it was demonstrated that the apoptosis index of the seminiferous epithelia cells in VC rat testes increased over time, as measured using TUNEL staining. Immunohistochemical analysis revealed that as the VC was prolonged, the expression of HIF-1α gradually increased while the expression of (apoptosis regulator Bcl-2) Bcl-2 gradually decreased. Furthermore, western blot analysis revealed that the protein expression of Bcl-2 decreased and apoptosis regulator Bax increased. Furthermore, HIF-1α, BNIP3, Beclin1 and microtubule associated protein 1 light chain 3 α (LC3)II/LC3I expression gradually increased. However, significant increases in Beclin 1 and LC3II/LC3I were only observed between the day 0 and day 30 groups. In addition, the expression of p62 significantly increased between day 0 and day 15, but gradually decreased between day 15 and day 45. The results of the present study revealed that VC can lead to testicular tissue hypoxia, and that the HIF-1α/BNIP3/Beclin1 autophagy signaling pathway may upregulate autophagy in VC rats testes. Thus, the association between autophagy and apoptosis may serve an important role in male infertility caused by VC.
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Affiliation(s)
- Shao-Ming Zhu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Ting Rao
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Xiao Yang
- Department of Gynaecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Jin-Zhuo Ning
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Wei-Ming Yu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Yuan Ruan
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Run Yuan
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Cheng-Long Li
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Kun Jiang
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Wei Hu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Hao-Yong Li
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Fan Cheng
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
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de Los Reyes T, Locke J, Afshar K. Varicoceles in the pediatric population: Diagnosis, treatment, and outcomes. Can Urol Assoc J 2017; 11:S34-S39. [PMID: 28265315 DOI: 10.5489/cuaj.4340] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Varicocele is commonly encountered in adolescents. There are still many controversies regarding pathophysiology, health effects, clinical significance, and optimum treatment of this condition. This article reviews the current evidence pertaining to children and adolescents with varicocele. This group present a unique and somehow challenging situation, since they are still going through pubertal changes that may confound the effects of the disease and its treatment on the developing testes.
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Affiliation(s)
- Thomas de Los Reyes
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Jennifer Locke
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Kourosh Afshar
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
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Ni K, Steger K, Yang H, Wang H, Hu K, Chen B. Expression and Role of Leptin under Hypoxic Conditions in Human Testis: Organotypic In Vitro Culture Experiment and Clinical Study on Patients with Varicocele. J Urol 2015; 193:360-7. [PMID: 24980614 DOI: 10.1016/j.juro.2014.06.072] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/19/2014] [Indexed: 12/18/2022]
Affiliation(s)
- Kai Ni
- Department of Urology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai Institute of Andrology, Shanghai, People's Republic of China
- Department of Urology, Pediatric Urology and Andrology, Section Molecular Andrology, Justus Liebig University Giessen, Giessen, Germany
| | - Klaus Steger
- Department of Urology, Pediatric Urology and Andrology, Section Molecular Andrology, Justus Liebig University Giessen, Giessen, Germany
| | - Hao Yang
- Department of Urology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai Institute of Andrology, Shanghai, People's Republic of China
| | - Hongxiang Wang
- Department of Urology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai Institute of Andrology, Shanghai, People's Republic of China
| | - Kai Hu
- Department of Urology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai Institute of Andrology, Shanghai, People's Republic of China
| | - Bin Chen
- Department of Urology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai Institute of Andrology, Shanghai, People's Republic of China
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Hu W, Zhou PH, Zhang XB, Xu CG, Wang W. Roles of adrenomedullin and hypoxia-inducible factor 1 alpha in patients with varicocele. Andrologia 2014; 47:951-7. [PMID: 25335788 DOI: 10.1111/and.12363] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/20/2014] [Indexed: 11/27/2022] Open
Affiliation(s)
- W. Hu
- Department of Urology; Renmin Hospital of Wuhan University; Wuhan Hubei Province China
| | - P.-H. Zhou
- Department of Orthopedics; Renmin Hospital of Wuhan University; Wuhan Hubei Province China
| | - X.-B. Zhang
- Department of Urology; Renmin Hospital of Wuhan University; Wuhan Hubei Province China
| | - C.-G. Xu
- Department of Urology; Renmin Hospital of Wuhan University; Wuhan Hubei Province China
| | - W. Wang
- Department of Urology; Renmin Hospital of Wuhan University; Wuhan Hubei Province China
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Increases in interleukin-6 and interferon-gamma levels is progressive in immature rats with varicocele. Ir J Med Sci 2014; 184:531-7. [DOI: 10.1007/s11845-014-1167-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 06/29/2014] [Indexed: 10/24/2022]
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Palladino MA, Shah A, Tyson R, Horvath J, Dugan C, Karpodinis M. Myeloid cell leukemia-1 (Mc1-1) is a candidate target gene of hypoxia-inducible factor-1 (HIF-1) in the testis. Reprod Biol Endocrinol 2012; 10:104. [PMID: 23216940 PMCID: PMC3556106 DOI: 10.1186/1477-7827-10-104] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 11/27/2012] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Spermatic cord torsion can lead to testis ischemia (I) and subsequent ischemia-reperfusion (I/R) causing germ cell-specific apoptosis. Previously, we demonstrated that the hypoxia-inducible factor-1 (HIF-1) transcription factor, a key regulator of physiological responses to hypoxia, is abundant in Leydig cells in normoxic and ischemic testes. We hypothesize that testicular HIF-1 activates the expression of antiapoptotic target genes to protect Leydig cells from apoptosis. In silico analysis of testis genes containing a consensus hypoxia response element (HRE, 5'-RCGTG-3') identified myeloid cell leukemia-1 (Mcl-1) as a potential HIF-1 target gene. The purpose of this study was to determine whether HIF-1 shows DNA-binding activity in normoxic and ischemic testes and whether Mcl-1 is a target gene of testicular HIF-1. METHODS The testicular HIF-1 DNA-binding capacity was analyzed in vitro using a quantitative enzyme-linked immunosorbent assay (ELISA) and electrophoretic mobility shift assays (EMSA). MCL-1 protein expression was evaluated by immunoblot analysis and immunohistochemistry. The binding of testicular HIF-1 to the Mcl-1 gene was examined via chromatin immunoprecipitation (ChIP) analysis. RESULTS The ELISA and EMSA assays demonstrated that testicular HIF-1 from normoxic and ischemic testes binds DNA equally strongly, suggesting physiological roles for HIF-1 in the normoxic testis, unlike most tissues in which HIF-1 is degraded under normoxic conditions and is only activated by hypoxia. MCL-1 protein was determined to be abundant in both normoxic and ischemic testes and expressed in Leydig cells. In a pattern identical to that of HIF-1 expression, the steady-state levels of MCL-1 were not significantly affected by I or I/R and MCL-1 co-localized with HIF-1α in Leydig cells. Chromatin immunoprecipitation (ChIP) analysis using a HIF-1 antibody revealed sequences enriched for the Mcl-1 promoter. CONCLUSIONS The results demonstrated that, unlike what is observed in most tissues, HIF-1 displays DNA-binding activity in both normoxic and ischemic testes, and Mcl-1 may be a key target gene of testicular HIF-1 with potential roles in the antiapoptotic protection of Leydig cells.
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Affiliation(s)
- Michael A Palladino
- Department of Biology, Monmouth University, 400 Cedar Avenue, West Long Branch, NJ 07764, USA.
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Agarwal A, Hamada A, Esteves SC. Insight into oxidative stress in varicocele-associated male infertility: part 1. Nat Rev Urol 2012; 9:678-90. [PMID: 23165403 DOI: 10.1038/nrurol.2012.197] [Citation(s) in RCA: 188] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Varicocele is recognized as the leading cause of male infertility because it can impair spermatogenesis through several distinct pathophysiological mechanisms. Current evidence supports oxidative stress as a key element in the pathophysiology of varicocele-related infertility, although these mechanisms have not yet been fully described. Measurement of the reactive oxygen species and other markers of oxidative stress, including the levels of the antioxidant enzymes catalase and superoxide dismutase, can provide valuable information on the extent of oxidative stress and might guide therapeutic management strategies. The testis can respond to varicocele-associated cell stressors, such as heat stress, ischaemia or production of vasodilators (for example, nitric oxide) at the expense of the generation of excessive reactive oxygen species. These responses have their own implications in exacerbating the underlying oxidative stress and on the subsequent infertility.
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Affiliation(s)
- Ashok Agarwal
- Center for Reproductive Medicine, Glickman Urological and Kidney Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
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The hypoxic testicle: physiology and pathophysiology. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2012; 2012:929285. [PMID: 23056665 PMCID: PMC3465913 DOI: 10.1155/2012/929285] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Revised: 08/07/2012] [Accepted: 08/09/2012] [Indexed: 12/15/2022]
Abstract
Mammalian spermatogenesis is a complex biological process occurring in the seminiferous tubules in the testis. This process represents a delicate balance between cell proliferation, differentiation, and apoptosis. In most mammals, the testicles are kept in the scrotum 2 to 7°C below body core temperature, and the spermatogenic process proceeds with a blood and oxygen supply that is fairly independent of changes in other vascular beds in the body. Despite this apparently well-controlled local environment, pathologies such as varicocele or testicular torsion and environmental exposure to low oxygen (hypoxia) can result in changes in blood flow, nutrients, and oxygen supply along with an increased local temperature that may induce adverse effects on Leydig cell function and spermatogenesis. These conditions may lead to male subfertility or infertility. Our literature analyses and our own results suggest that conditions such as germ cell apoptosis and DNA damage are common features in hypoxia and varicocele and testicular torsion. Furthermore, oxidative damage seems to be present in these conditions during the initiation stages of germ cell damage and apoptosis. Other mechanisms like membrane-bound metalloproteinases and phospholipase A2 activation could also be part of the pathophysiological consequences of testicular hypoxia.
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[Comment to: «Increased expression of hypoxia-inducible factor-1α and connective tissue growth factor accompanied by fibrosis in the rat testis of varicocele»]. Actas Urol Esp 2012; 36:289-90. [PMID: 22206895 DOI: 10.1016/j.acuro.2011.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Accepted: 10/09/2011] [Indexed: 11/21/2022]
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