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Gao DD, Liu GQ, Chen YL, Ding N, Zhong JH, Liang GN, Deng WJ, Li PL, Su JR, Wang M, Huang JH, Hu M. Cellular mechanism underlying leptin-induced anion secretion of rat epididymal epithelial cells. Andrology 2024. [PMID: 38778669 DOI: 10.1111/andr.13656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/12/2024] [Accepted: 04/30/2024] [Indexed: 05/25/2024]
Abstract
BACKGROUND A large number of studies have shown that leptin plays an important role in the regulation of fertility via the hypothalamus-pituitary-gonad axis. However, its peripheral function in epididymis was still elusive. OBJECTIVE The purpose of this study was to determine the pro-secretion effect of leptin on the rat epididymal epithelium. MATERIALS AND METHODS In the present study, real-time quantitative polymerase chain reaction, western blot, and immunohistochemical analysis were employed to detect the expression pattern of leptin receptors in rat epididymis. The pro-secretion effect of leptin on epididymal epithelial cells was measured by short-circuit current, and the prostaglandin E2 and cyclic adenosine monophosphate level was evaluated by enzyme-linked immunosorbent assay. RESULTS We verified that the leptin receptor was located on the epididymal epithelium, with a relatively high expression level in corpus and cauda epididymis. Ussing chamber experiments showed that leptin stimulated a significant rise of the short-circuit current in rat epididymal epithelial cells, which could be abolished by the specific leptin receptor antagonist peptide Allo-aca, or by removing the ambient Cl- and HCO3 -. Furthermore, the leptin-stimulated short-circuit current response could be abrogated by blocking the apical cystic fibrosis transmembrane regulator or the basolateral Na+-K+-2Cl- cotransporter. Our pharmacological experiments manifested that interfering with the prostaglandin H synthase-2-prostaglandin E2-EP2/EP4-adenylate cyclase pathways could significantly blunt the cystic fibrosis transmembrane regulator-mediated anion secretion induced by leptin. The enzyme-linked immunosorbent assay demonstrated that leptin could induce a substantial increase in prostaglandin E2 release and cyclic adenosine monophosphate synthesis of primary cultured rat cauda epididymal epithelial cells. Our data also suggested that JAK2, ERK, and PI3K-dependent phosphorylation may be involved in the activation of prostaglandin H synthase-2 and the subsequent prostaglandin E2 production. CONCLUSIONS The present study demonstrated the pro-secretion function of leptin in rat epididymal epithelium via the activation of cystic fibrosis transmembrane regulator and Na+-K+-2Cl- cotransporter, which was dependent on the paracrine/autocrine prostaglandin E2 stimulated EP2/EP4-adenylate cyclase pathways, and thus contributed to the formation of an appropriate microenvironment essential for sperm maturation.
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Affiliation(s)
- Dong-Dong Gao
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Guo-Qing Liu
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Yi-Lin Chen
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Nan Ding
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Jia-Hui Zhong
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Guang-Nan Liang
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Wei-Ji Deng
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Pei-Lun Li
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Jia-Rui Su
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Ming Wang
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
| | - Jun-Hao Huang
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
- Dr. Neher's Biophysics Laboratory for Innovative Drug Discovery, State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau, China
| | - Min Hu
- Guangdong Provincial Key Laboratory of Sport and Health Promotion, Scientific Research Center, Guangzhou Sport University, Guangzhou, China
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Long-term arsenite exposure induces testicular toxicity by redox imbalance, G2/M cell arrest and apoptosis in mice. Toxicology 2019; 411:122-132. [DOI: 10.1016/j.tox.2018.09.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 09/06/2018] [Accepted: 09/26/2018] [Indexed: 01/22/2023]
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4
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Dallak M. Unacylated ghrelin stimulates steroidogenesis in lean rats and reverses reproductive dysfunction in high fat diet-fed rats. Syst Biol Reprod Med 2018; 65:129-146. [DOI: 10.1080/19396368.2018.1523971] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Mohammad Dallak
- Department of Physiology, College of Medicine, King Khalid University, Abha, Saudi Arabia
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5
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Ozkanli S, Basar MM, Selimoglu S, Erol B, Ozkanli O, Nurili F, Kahraman S. The ghrelin and orexin activity in testicular tissues of patients with idiopathic non-obstructive azoospermia. Kaohsiung J Med Sci 2018; 34:564-568. [PMID: 30309484 DOI: 10.1016/j.kjms.2018.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 03/25/2018] [Accepted: 04/10/2018] [Indexed: 10/28/2022] Open
Abstract
The aim of the present study is to evaluate the presence of ghrelin and orexin in the testicular tissue of patients who have undergone microscopic testicular sperm extraction (micro-TESE) due to idiopathic non-obstructive azoospermia. Seventy azoospermic cases were included in this study; serum hormone levels were measured and genetic investigations were performed. The patients were divided into two groups: micro-TESE (+) and micro-TESE (-). The number of Leydig cells and stained cells in the seminiferous tubules were counted under a light microscope, and we analyzed ghrelin and orexin activity. The relationship between serum hormone levels and ghrelin and orexin distributions in testicular tissue was evaluated according to micro-TESE results. While sperm was found in 33 cases (47.1%), micro-TESE was negative in 37 cases (52.9%). Peptide hormone activity in testicular tissue was higher in micro-TESE (+) cases. However, interstitial orexin (p = 0.038) and ghrelin (p = 0.002) activity showed statistically meaningful differences. Many different peptides, genes, and other unknown mechanisms play important roles in testicular function. In particular, the peptides orexin and ghrelin may play regulatory roles in testicular function in humans.
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Affiliation(s)
- Seyma Ozkanli
- Department of Pathology, Faculty of Medicine, Istanbul Medeniyet University, Istanbul, Turkey.
| | | | | | - Bulent Erol
- Department of Urology, Faculty of Medicine, Istanbul Medeniyet University, Istanbul, Turkey
| | - Oguz Ozkanli
- Department of Anesthesiology, Memorial Sisli Hospital, Istanbul, Turkey
| | - Fuad Nurili
- Department of Radiology, Memorial Sloan Kettering Cancer Center, USA
| | - Semra Kahraman
- Department of IVF, Memorial Sisli Hospital, Istanbul, Turkey
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6
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Sominsky L, Hodgson DM, McLaughlin EA, Smith R, Wall HM, Spencer SJ. Linking Stress and Infertility: A Novel Role for Ghrelin. Endocr Rev 2017; 38:432-467. [PMID: 28938425 DOI: 10.1210/er.2016-1133] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 07/24/2017] [Indexed: 12/23/2022]
Abstract
Infertility affects a remarkable one in four couples in developing countries. Psychological stress is a ubiquitous facet of life, and although stress affects us all at some point, prolonged or unmanageable stress may become harmful for some individuals, negatively impacting on their health, including fertility. For instance, women who struggle to conceive are twice as likely to suffer from emotional distress than fertile women. Assisted reproductive technology treatments place an additional physical, emotional, and financial burden of stress, particularly on women, who are often exposed to invasive techniques associated with treatment. Stress-reduction interventions can reduce negative affect and in some cases to improve in vitro fertilization outcomes. Although it has been well-established that stress negatively affects fertility in animal models, human research remains inconsistent due to individual differences and methodological flaws. Attempts to isolate single causal links between stress and infertility have not yet been successful due to their multifaceted etiologies. In this review, we will discuss the current literature in the field of stress-induced reproductive dysfunction based on animal and human models, and introduce a recently unexplored link between stress and infertility, the gut-derived hormone, ghrelin. We also present evidence from recent seminal studies demonstrating that ghrelin has a principal role in the stress response and reward processing, as well as in regulating reproductive function, and that these roles are tightly interlinked. Collectively, these data support the hypothesis that stress may negatively impact upon fertility at least in part by stimulating a dysregulation in ghrelin signaling.
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Affiliation(s)
- Luba Sominsky
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Victoria 3083, Australia
| | - Deborah M Hodgson
- School of Psychology, Faculty of Science and IT, The University of Newcastle, New South Wales 2308, Australia
| | - Eileen A McLaughlin
- School of Biological Sciences, Faculty of Science, The University of Auckland, Auckland 1010, New Zealand.,School of Environmental & Life Sciences, Faculty of Science and IT, The University of Newcastle, New South Wales 2308, Australia
| | - Roger Smith
- Mothers and Babies Research Centre, Hunter Medical Research Institute, Lookout Road, New Lambton Heights, New South Wales 2305, Australia.,Priority Research Centre in Reproductive Science, The University of Newcastle, New South Wales 2308, Australia
| | - Hannah M Wall
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Victoria 3083, Australia
| | - Sarah J Spencer
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Victoria 3083, Australia
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7
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Shimizu T, Sato T, Tsukiyama K, Fujita H, Kato S, Hoizumi M, Shirasawa H, Narita T, Terada Y, Seino Y, Yamada Y. Food Intake Affects Sperm-Egg Fusion Through the GIP/PSG17 Axis in Mice. Endocrinology 2017; 158:2134-2144. [PMID: 28430907 DOI: 10.1210/en.2016-1861] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 04/14/2017] [Indexed: 12/30/2022]
Abstract
In addition to overeating, starvation also reduces fecundity in mammals. However, little is known about the molecular mechanisms linking food intake to fertility, especially in males. Gastric inhibitory polypeptide (GIP), which is released from intestinal K-cells after meal ingestion, stimulates insulin secretion from pancreatic β-cells through the action of incretin and has several extrapancreatic effects. Here, we identified GIP receptor (Gipr) expression in mouse spermatids. Microarray analysis revealed that pregnancy-specific glycoprotein 17 (Psg17), a potential CD9-binding partner, was significantly decreased in GIP receptor-knockout (Gipr-/-) testes. Glycosylphosphatidylinositol-anchored PSG17 was expressed on the surface of acrosome-reacted sperm, and Gipr-/- sperm led to a lower fertilization rate in vitro, compared with that of Gipr+/+ sperm, both in the absence and presence of the zona pellucida. Plasma GIP concentrations and Psg17 messenger RNA (mRNA) were immediately increased in the testis after a single meal, whereas ingestion of a chronic high-fat diet markedly decreased Gipr and Psg17 mRNA. These results suggest that reduced GIP signaling, by decreased GIP levels or the downregulation of Gipr, is associated with the reduction of fecundity due to starvation or overeating. Thus, proper regulation of GIP signaling in the testis could be a potential unique therapeutic target for male infertility in obese and diabetic individuals.
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Affiliation(s)
- Tatsunori Shimizu
- Department of Endocrinology, Diabetes, and Geriatric Medicine, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Takehiro Sato
- Department of Endocrinology, Diabetes, and Geriatric Medicine, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Katsushi Tsukiyama
- Department of Endocrinology, Diabetes, and Geriatric Medicine, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Hiroki Fujita
- Department of Endocrinology, Diabetes, and Geriatric Medicine, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Shunsuke Kato
- Department of Endocrinology, Diabetes, and Geriatric Medicine, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Manabu Hoizumi
- Department of Endocrinology, Diabetes, and Geriatric Medicine, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Hiromitsu Shirasawa
- Department of Obstetrics and Gynecology, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Takuma Narita
- Department of Endocrinology, Diabetes, and Geriatric Medicine, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Yukihiro Terada
- Department of Obstetrics and Gynecology, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Yutaka Seino
- Kansai Electric Power Medical Research Institute, Osaka 553-0003, Japan
| | - Yuichiro Yamada
- Department of Endocrinology, Diabetes, and Geriatric Medicine, Akita University Graduate School of Medicine, Akita 010-8543, Japan
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8
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Evans MC, Anderson GM. Neuroendocrine integration of nutritional signals on reproduction. J Mol Endocrinol 2017; 58:R107-R128. [PMID: 28057770 DOI: 10.1530/jme-16-0212] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 01/05/2017] [Indexed: 12/28/2022]
Abstract
Reproductive function in mammals is energetically costly and therefore tightly regulated by nutritional status. To enable this integration of metabolic and reproductive function, information regarding peripheral nutritional status must be relayed centrally to the gonadotropin-releasing hormone (GNRH) neurons that drive reproductive function. The metabolically relevant hormones leptin, insulin and ghrelin have been identified as key mediators of this 'metabolic control of fertility'. However, the neural circuitry through which they act to exert their control over GNRH drive remains incompletely understood. With the advent of Cre-LoxP technology, it has become possible to perform targeted gene-deletion and gene-rescue experiments and thus test the functional requirement and sufficiency, respectively, of discrete hormone-neuron signaling pathways in the metabolic control of reproductive function. This review discusses the findings from these investigations, and attempts to put them in context with what is known from clinical situations and wild-type animal models. What emerges from this discussion is clear evidence that the integration of nutritional signals on reproduction is complex and highly redundant, and therefore, surprisingly difficult to perturb. Consequently, the deletion of individual hormone-neuron signaling pathways often fails to cause reproductive phenotypes, despite strong evidence that the targeted pathway plays a role under normal physiological conditions. Although transgenic studies rarely reveal a critical role for discrete signaling pathways, they nevertheless prove to be a good strategy for identifying whether a targeted pathway is absolutely required, critically involved, sufficient or dispensable in the metabolic control of fertility.
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Affiliation(s)
- Maggie C Evans
- Centre for Neuroendocrinology and Department of AnatomyUniversity of Otago School of Medical Sciences, Dunedin, New Zealand
| | - Greg M Anderson
- Centre for Neuroendocrinology and Department of AnatomyUniversity of Otago School of Medical Sciences, Dunedin, New Zealand
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9
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Dong YS, Hou WG, Li Y, Liu DB, Hao GZ, Zhang HF, Li JC, Zhao J, Zhang S, Liang GB, Li W. Unexpected requirement for a binding partner of the syntaxin family in phagocytosis by murine testicular Sertoli cells. Cell Death Differ 2015; 23:787-800. [PMID: 26494466 DOI: 10.1038/cdd.2015.139] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 09/14/2015] [Accepted: 09/25/2015] [Indexed: 01/07/2023] Open
Abstract
Testicular phagocytosis by Sertoli cells (SCs) plays an essential role in the efficient clearance of apoptotic spermatogenic cells under both physiological and pathological conditions. However, the molecular mechanism underlying this unique process is poorly understood. Herein, we report for the first time that α-taxilin protein (TXLNA), a binding partner of the syntaxin family that functions as a central player in the intracellular vesicle traffic, was dominantly expressed in SCs. Induction of apoptosis in murine meiotic spermatocytes and haploid spermatids by busulfan treatment stimulated a significant increase of TXLNA in SCs at day (d) 14 and d 24 after busulfan treatment, respectively. Consistently, TXLNA expression was steadily upregulated when SCs were co-cultured with apoptotic germ cells (GCs). Moreover, using siRNA treatment, we found that ablation of endogenous TXLNA significantly impaired the phagocytotic capacity of SCs and thereby resulted in defective spermiogenesis and reduced fertility during the late recovery after testicular heat stress. Mechanistically, upregulation of TXLNA expression by apoptotic GCs was associated with the stabilization of ATP-binding cassette transporter 1 (ABCA1), a transporter-mediated lipid efflux from SCs and influencing male fertility. TXLNA acted as an upstream suppressor of ABCA1 ubiquitination and thus promoted ABCA1 stability and accumulation following GC apoptosis. We further provide in vitro evidence that epidermal growth factor receptor (EGFR)-mediated phosphorylation regulated ABCA1 ubiquitination and was enhanced by TXLNA deficiency during testicular phagocytosis. Taken together, the TXLNA/ABCA1 cascade may serve as an important feedback mechanism to modulate the magnitude of subsequent phagocytotic process of SCs in response to testicular injury.
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Affiliation(s)
- Y-s Dong
- Department of Neurosurgery, General Hospital of Shenyang Military Area Command, Shenyang 110016, China.,Department of Histology and Embryology, Fourth Military Medical University, Xi'an 710032, China
| | - W-g Hou
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Y Li
- Department of Air Logistics, 463rd Hospital of PLA, Shenyang 110042, China
| | - D-b Liu
- Department of Air Logistics, 463rd Hospital of PLA, Shenyang 110042, China
| | - G-z Hao
- Department of Neurosurgery, General Hospital of Shenyang Military Area Command, Shenyang 110016, China
| | - H-f Zhang
- Department of Neurosurgery, General Hospital of Shenyang Military Area Command, Shenyang 110016, China
| | - J-c Li
- Department of Neurosurgery, General Hospital of Shenyang Military Area Command, Shenyang 110016, China
| | - J Zhao
- Department of Histology and Embryology, Fourth Military Medical University, Xi'an 710032, China
| | - S Zhang
- Department of Gynecology and Obstetrics, Reproductive Medicine Center, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, China
| | - G-b Liang
- Department of Neurosurgery, General Hospital of Shenyang Military Area Command, Shenyang 110016, China
| | - W Li
- Department of Histology and Embryology, Fourth Military Medical University, Xi'an 710032, China
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Abnormal Accumulation of Collagen Type I Due to the Loss of Discoidin Domain Receptor 2 (Ddr2) Promotes Testicular Interstitial Dysfunction. PLoS One 2015; 10:e0131947. [PMID: 26158267 PMCID: PMC4497730 DOI: 10.1371/journal.pone.0131947] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 06/08/2015] [Indexed: 02/07/2023] Open
Abstract
Background Loss of functional allele for discoidin domain receptor 2 (Ddr2) results in impaired Leydig cell response to luteinizing hormone (LH), low testosterone production and arrested spermatogenesis in older male Ddr2slie/slie mice. However, the underlying mechanism responsible for this phenotype remains unknown. Herein, we reported for the first time that the deregulated expression of Ddr2 cognate ligand, namely collagen type I (COL1), may account for the disruption of the testicular steroidogenesis in Ddr2slie/slie mutant testes. Methodology/Principal Findings Expression of Ddr2 increased gradually along postnatal development, whereas COL1 expression became negligible from adulthood onwards. In Ddr2slie/slie mutant testis, however, in contrast to the undetectable staining of Ddr2, COL1 expression was constantly detected, with the highest values detected during adulthood. In the experimental vasectomy model, Ddr2slie/slie mutant mice exhibited an early androgen deficiency than wild-type mice, along with the accumulation of fibrotic tissue in the interstitium. Functionally, ablation of endogenous Ddr2 resulted in a significant decrease of testosterone (T) level in TM3 cells in the presence of higher concentration of COL1 treatment. Conversely, overexpression of Ddr2 could help TM3 cells to maintain a normal testicular steroidogenesis even in the presence of high concentration of COL1. Additionally, attenuated expression of Ddr2 correlates to the deregulated level of serum T levels in human pathological testes. Conclusions Abnormal accumulation of interstitial COL1 may be responsible for the steroidogenic dysfunction in Ddr2slie/slie mutant testes.
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Li W, Fu J, Zhang S, Zhao J, Xie N, Cai G. The proteasome inhibitor bortezomib induces testicular toxicity by upregulation of oxidative stress, AMP-activated protein kinase (AMPK) activation and deregulation of germ cell development in adult murine testis. Toxicol Appl Pharmacol 2015; 285:98-109. [PMID: 25886977 DOI: 10.1016/j.taap.2015.04.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/18/2015] [Accepted: 04/04/2015] [Indexed: 01/02/2023]
Abstract
Understanding how chemotherapeutic agents mediate testicular toxicity is crucial in light of compelling evidence that male infertility, one of the severe late side effects of intensive cancer treatment, occurs more often than they are expected to. Previous study demonstrated that bortezomib (BTZ), a 26S proteasome inhibitor used to treat refractory multiple myeloma (MM), exerts deleterious impacts on spermatogenesis in pubertal mice via unknown mechanisms. Here, we showed that intermittent treatment with BTZ resulted in fertility impairment in adult mice, evidenced by testicular atrophy, desquamation of immature germ cells and reduced caudal sperm storage. These deleterious effects may originate from the elevated apoptosis in distinct germ cells during the acute phase and the subsequent disruption of Sertoli-germ cell anchoring junctions (AJs) during the late recovery. Mechanistically, balance between AMP-activated protein kinase (AMPK) activation and Akt/ERK pathway appeared to be indispensable for AJ integrity during the late testicular recovery. Of particular interest, the upregulated testicular apoptosis and the following disturbance of Sertoli-germ cell interaction may both stem from the excessive oxidative stress elicited by BTZ exposure. We also provided the in vitro evidence that AMPK-dependent mechanisms counteract follicle-stimulating hormone (FSH) proliferative effects in BTZ-exposed Sertoli cells. Collectively, BTZ appeared to efficiently prevent germ cells from normal development via multiple mechanisms in adult mice. Employment of antioxidants and/or AMPK inhibitor may represent an attractive strategy of fertility preservation in male MM patients exposed to conventional BTZ therapy and warrants further investigation.
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Affiliation(s)
- Wei Li
- Department of Human Anatomy, Histology and Embryology, Fourth Military Medical University, Xi'an 710032, PR China
| | - Jianfang Fu
- Department of Endocrinology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China
| | - Shun Zhang
- Reproductive Medicine Center, Department of Gynecology and Obstetrics, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, PR China
| | - Jie Zhao
- Department of Human Anatomy, Histology and Embryology, Fourth Military Medical University, Xi'an 710032, PR China
| | - Nianlin Xie
- Department of Thoracic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, PR China.
| | - Guoqing Cai
- Department of Gynaecology and Obstetrics, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China.
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12
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Catak Z, Aydin S, Sahin I, Kuloglu T, Aksoy A, Dagli AF. Regulatory neuropeptides (ghrelin, obestatin and nesfatin-1) levels in serum and reproductive tissues of female and male rats with fructose-induced metabolic syndrome. Neuropeptides 2014; 48:167-77. [PMID: 24786976 DOI: 10.1016/j.npep.2014.04.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 04/02/2014] [Accepted: 04/07/2014] [Indexed: 12/15/2022]
Abstract
Although, the exact mechanisms underlying the development of the metabolic syndrome (MetS) are not still completely understood, obesity, circulated peptide hormone levels and their interaction with genetic factors are considered largely responsible. The purpose of this study is to explore how the levels of ghrelin, obestatin (OBS) and NUCB2/nesfatin-1 (NES)/NUCB2 change in serum and the reproductive tissues of female and male rats with fructose-induced metabolic syndrome, and whether the levels of each hormone is correlated with the hormones involved with fertility. Experiments were conducted on 5-week-old Sprague-Dawley male and female rats assigned to either a control group or a MetS group. Controls were fed standard rat food and water ad libitum, while the MetS group was fed standard food with 10% (v/v) fructose solution added to their drinking water for 12 weeks with a 12/12h photoperiod circle. Then, all animals were sacrificed after a one night fast. Peptides levels in the serum and reproductive tissues of rats were studied using the ELISA method while the immunoreactivity of reproductive system peptide hormones were shown by immunohistochemical staining method. Furthermore, the other biochemical parameters were measured using Konelab-60 equipment and infertility hormones were measured with Immulite2000. Fasting serum insulin, glucose, triglyceride, alanine aminotransferase (ALT), gamma glutamyl transpeptidase (GGT), low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC) levels were statistically significantly higher, and the amount of high density lipoprotein cholesterol (HDL-C) was significantly lower, in the MetS groups. Serum and tissue supernatant NES levels were significantly higher in the rats with MetS than the control group. Ghrelin, OBS and NES were expressed in the cytoplasm, concentrated around the apical parts of the epithelial cells in the reproductive tissues of the rats. The amounts of ghrelin were lower in the reproductive tissues of the animals with MetS, while NES levels in the same tissues increased. Obestatin also decreased, though not in the seminal glands.
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Affiliation(s)
- Zekiye Catak
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey
| | - Suleyman Aydin
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey.
| | - Ibrahim Sahin
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey; Department of Histology and Embryology, Medical School, Erzincan University, 24030 Erzincan, Turkey
| | - Tuncay Kuloglu
- Department of Histology and Embryology, Medical School, Firat University, 23119 Elazig, Turkey
| | - Aziz Aksoy
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey; Department of Nutrition and Dietetics, Bitlis Eren University, 13000 Bitlis, Turkey
| | - Adile Ferda Dagli
- Department of Medical Pathology, Medical School, Inonu University, 44280 Malatya, Turkey
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Upregulation and nuclear translocation of testicular ghrelin protects differentiating spermatogonia from ionizing radiation injury. Cell Death Dis 2014; 5:e1248. [PMID: 24853426 PMCID: PMC4047875 DOI: 10.1038/cddis.2014.223] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 04/13/2014] [Accepted: 04/18/2014] [Indexed: 11/13/2022]
Abstract
Proper control of apoptotic signaling is important for maintenance of testicular homeostasis after ionizing radiation (IR). Herein, we challenged the hypothesis that ghrelin, a pleiotropic modulator, is potentially involved in IR-induced germ cell injury. Lower body exposure to 2 Gy of IR induced a notable increase of ghrelin expression in the nuclear of differentiating spermatogonia at defined stages, with an impairment in the Leydig cells (LCs)-expressing ghrelin. Unexpectedly, inhibition of the ghrelin pathway by intraperitoneal injection of a specific GHS-R1α antagonist enhanced spermatogonia elimination by apoptosis during the early recovery following IR, and thereafter resulted in impaired male fertility, suggesting that the anti-apoptotic effects of evoked ghrelin, although transient along testicular IR injury, have a profound influence on the post-injury recovery. In addition, inhibition of ghrelin signaling resulted in a significant increase in the intratesticular testosterone (T) level at the end of 21 days after IR, which should stimulate the spermatogenic recovery from surviving spermatogonia to a certain extent during the late stage. We further demonstrated that the upregulation and nuclear trafficking of ghrelin, elaborately regulated by IR-elicited antioxidant system in spermatogonia, may act through a p53-dependent mechanism. The elicitation of ghrelin expression by IR stress, the regulation of ghrelin expression by IR-induced oxidative stress and the interaction between p53 and ghrelin signaling during IR injury were confirmed in cultured spermatogonia. Hence, our results represent the first evidence in support of a radioprotective role of ghrelin in the differentiating spermatogonia. The acutely, delicate regulation of local-produced ghrelin appears to be a fine-tune mechanism modulating the balance between testicular homeostasis and early IR injury.
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Leptin signaling in GABA neurons, but not glutamate neurons, is required for reproductive function. J Neurosci 2013; 33:17874-83. [PMID: 24198376 DOI: 10.1523/jneurosci.2278-13.2013] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The adipocyte-derived hormone leptin acts in the brain to modulate the central driver of fertility: the gonadotropin releasing hormone (GnRH) neuronal system. This effect is indirect, as GnRH neurons do not express leptin receptors (LEPRs). Here we test whether GABAergic or glutamatergic neurons provide the intermediate pathway between the site of leptin action and the GnRH neurons. Leptin receptors were deleted from GABA and glutamate neurons using Cre-Lox transgenics, and the downstream effects on puberty onset and reproduction were examined. Both mouse lines displayed the expected increase in body weight and region-specific loss of leptin signaling in the hypothalamus. The GABA neuron-specific LEPR knock-out females and males showed significantly delayed puberty onset. Adult fertility observations revealed that these knock-out animals have decreased fecundity. In contrast, glutamate neuron-specific LEPR knock-out mice displayed normal fertility. Assessment of the estrogenic hypothalamic-pituitary-gonadal axis regulation in females showed that leptin action on GABA neurons is not necessary for estradiol-mediated suppression of tonic luteinizing hormone secretion (an indirect measure of GnRH neuron activity) but is required for regulation of a full preovulatory-like luteinizing hormone surge. In conclusion, leptin signaling in GABAergic (but not glutamatergic neurons) plays a critical role in the timing of puberty onset and is involved in fertility regulation throughout adulthood in both sexes. These results form an important step in explaining the role of central leptin signaling in the reproductive system. Limiting the leptin-to-GnRH mediators to GABAergic cells will enable future research to focus on a few specific types of neurons.
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Moretti E, Vindigni C, Tripodi SA, Mazzi L, Nuti R, Figura N, Collodel G. Immunolocalisation of ghrelin and obestatin in human testis, seminal vesicles, prostate and spermatozoa. Andrologia 2013; 46:979-85. [PMID: 24147986 DOI: 10.1111/and.12183] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/11/2013] [Indexed: 12/18/2022] Open
Abstract
The role of ghrelin and obestatin in male reproduction has not completely been clarified. We explored ghrelin and obestatin localisation in the male reproductive system. Polyclonal antibodies anti-ghrelin and anti-obestatin were used to detect the expression of these hormones in human testis, prostate and seminal vesicles by immunocytochemistry, while in ejaculated and swim up selected spermatozoa by immunofluorescence. Sertoli cells were positive for both peptides and Leydig cells for ghrelin; germ cells were negative for both hormones. Mild signals for ghrelin and obestatin were observed in rete testis; efferent ductules were the most immune reactive region for both peptides. Epididymis was moderately positive for ghrelin; vas deferens and seminal vesicles showed intense obestatin and moderate ghrelin labelling; prostate tissue expressed obestatin alone. Ejaculated and selected spermatozoa were positive for both peptides in different head and tail regions. This study confirms ghrelin localisation in Leydig and Sertoli cells; the finding that ghrelin is expressed in rete testis, epididymis, vas deferens and seminal vesicles is novel, as well as the localisation of obestatin in almost all tracts of the male reproductive system. This research could offer insights for stimulating other studies, particularly on the role of obestatin in sperm physiology, which is still obscure.
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Affiliation(s)
- E Moretti
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
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