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Falvo S, Santillo A, Di Fiore MM, Venditti M, Grillo G, Latino D, Baccari I, Petito G, Chieffi Baccari G. New Insights into D-Aspartate Signaling in Testicular Activity. Cells 2024; 13:1400. [PMID: 39195288 DOI: 10.3390/cells13161400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2024] [Revised: 08/19/2024] [Accepted: 08/20/2024] [Indexed: 08/29/2024] Open
Abstract
D-aspartate (D-Asp) is an amino acid found in high concentrations in the testis and pituitary gland. Increasing evidence suggests that D-Asp promotes spermatogenesis by activating testosterone production in the Leydig cells via LH release from the pituitary gland. In vitro studies indicate that D-Asp may also influence steroidogenesis and spermatogenesis through autocrine and paracrine signals. D-Asp enhances StAR and steroidogenic enzyme expressions, facilitating testicular cell proliferation via the GluR/ERK1/2 pathway. Moreover, it supports spermatogenesis by enhancing the mitochondrial function in spermatocytes, aiding in the metabolic shift during meiosis. Enhanced mitochondrial function, along with improved MAM stability and reduced ER stress, has been observed in Leydig and Sertoli cells treated with D-Asp, indicating potential benefits in steroidogenesis and spermatogenesis efficiency. Conversely, D-Asp exerts a notable anti-apoptotic effect in the testis via the AMPAR/AKT pathway, potentially mediated by antioxidant enzyme modulation to mitigate testicular oxidative stress. This review lays the groundwork for future investigations into the molecules promoting spermatogenesis by stimulating endogenous testosterone biosynthesis, with D-amino acids emerging as promising candidates.
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Affiliation(s)
- Sara Falvo
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania 'Luigi Vanvitelli', 81100 Caserta, Italy
| | - Alessandra Santillo
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania 'Luigi Vanvitelli', 81100 Caserta, Italy
| | - Maria Maddalena Di Fiore
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania 'Luigi Vanvitelli', 81100 Caserta, Italy
| | - Massimo Venditti
- Department of Experimental Medicine, University of Campania 'Luigi Vanvitelli', 80138 Napoli, Italy
| | - Giulia Grillo
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania 'Luigi Vanvitelli', 81100 Caserta, Italy
| | - Debora Latino
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania 'Luigi Vanvitelli', 81100 Caserta, Italy
| | - Isabella Baccari
- Department of Experimental Medicine, University of Campania 'Luigi Vanvitelli', 80138 Napoli, Italy
| | - Giuseppe Petito
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania 'Luigi Vanvitelli', 81100 Caserta, Italy
| | - Gabriella Chieffi Baccari
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania 'Luigi Vanvitelli', 81100 Caserta, Italy
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Zhang Y, Shi W, Zhang M, Xu L, Wu L, Li C, Zhang Z, Cao W, Zhang J, Zeng Q, Sun S. Exposure to PM 2.5, seminal plasma metabolome, and semen quality among Chinese adult men: Association and potential mediation analyses. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132602. [PMID: 37748305 DOI: 10.1016/j.jhazmat.2023.132602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 09/17/2023] [Accepted: 09/20/2023] [Indexed: 09/27/2023]
Abstract
Exposure to ambient fine particulate matter (PM2.5) has been linked to a decline in semen quality, but the underlying mechanisms for this association remain unclear. We aimed to examine whether specific metabolites act as mediators in the association between PM2.5 exposure and changes in semen quality. We conducted untargeted metabolomics analysis using LC-MS/MS platforms to identified seminal plasma metabolites associated with various semen quality parameters among 200 Chinese adult men. Additionally, we performed mediation analyses to examine the effects of the seminal plasma metabolites on the association between PM2.5 exposure and semen quality. We identified 140 differential metabolites between the normal and abnormal semen groups, involving two metabolic pathways: Alanine, aspartate and glutamate metabolism, and Aminoacyl-tRNA biosynthesis. We additionally identified 7 specific seminal plasma metabolites that were associated with discrepant metabolic networks related to semen quality. The mediation analysis revealed that D-Aspartate might play a mediating role in the adverse effects of ambient PM2.5 exposure on both total and progressive motility during spermatogenesis period (70-90 days before ejaculation), with a proportion of mediation up to 16% and 17%, respectively. Exposure to PM2.5 was associated with alterations in D-Aspartate levels, which might partially mediate the association between PM2.5 and reduced sperm motility.
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Affiliation(s)
- Yangchang Zhang
- School of Public Health, Capital Medical University, Beijing 100069, China
| | - Wanying Shi
- School of Public Health, Capital Medical University, Beijing 100069, China
| | - Min Zhang
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Lufei Xu
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Human Resources, Peking University Cancer Hospital & Institute, China
| | - Lizhi Wu
- Zhejiang Provincial Center for Disease Control and Prevention, 3399 Bin Sheng Road Binjiang District, Hangzhou 310051, China
| | - Chunrong Li
- Chengdu Women's and Children's Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 611731, China
| | - Zhenyu Zhang
- Department of Global Health, Peking University School of Public Health, Beijing, China; Institute for Global Health and Development, Peking University, Beijing 100191, China
| | - Wangnan Cao
- Department of Social Medicine and Health Education, School of Public Health, Peking University, Beijing 100191, China
| | - Jie Zhang
- School of Public Health, Xiamen University, Xiamen, China
| | - Qiang Zeng
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
| | - Shengzhi Sun
- School of Public Health, Capital Medical University, Beijing 100069, China; School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China.
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Katane M, Homma H. Biosynthesis and Degradation of Free D-Amino Acids and Their Physiological Roles in the Periphery and Endocrine Glands. Biol Pharm Bull 2024; 47:562-579. [PMID: 38432912 DOI: 10.1248/bpb.b23-00485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2024]
Abstract
It was long believed that D-amino acids were either unnatural isomers or laboratory artifacts, and that the important functions of amino acids were exerted only by L-amino acids. However, recent investigations have revealed a variety of D-amino acids in mammals that play important roles in physiological functions, including free D-serine and D-aspartate that are crucial in the central nervous system. The functions of several D-amino acids in the periphery and endocrine glands are also receiving increasing attention. Here, we present an overview of recent advances in elucidating the physiological roles of D-amino acids, especially in the periphery and endocrine glands.
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Affiliation(s)
- Masumi Katane
- Medicinal Research Laboratories, Graduate School of Pharmaceutical Sciences, Kitasato University
| | - Hiroshi Homma
- Laboratory of Analytical Chemistry, Graduate School of Pharmaceutical Sciences, Kitasato University
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Santillo A, Falvo S, Venditti M, Di Maio A, Chieffi Baccari G, Errico F, Usiello A, Minucci S, Di Fiore MM. D-Aspartate Depletion Perturbs Steroidogenesis and Spermatogenesis in Mice. Biomolecules 2023; 13:biom13040621. [PMID: 37189369 DOI: 10.3390/biom13040621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/23/2023] [Accepted: 03/28/2023] [Indexed: 04/01/2023] Open
Abstract
High levels of free D-aspartate (D-Asp) are present in vertebrate testis during post-natal development, coinciding with the onset of testosterone production, which suggests that this atypical amino acid might participate in the regulation of hormone biosynthesis. To elucidate the unknown role of D-Asp on testicular function, we investigated steroidogenesis and spermatogenesis in a one-month-old knockin mouse model with the constitutive depletion of D-Asp levels due to the targeted overexpression of D-aspartate oxidase (DDO), which catalyzes the deaminative oxidation of D-Asp to generate the corresponding α-keto acid, oxaloacetate, hydrogen peroxide, and ammonium ions. In the Ddo knockin mice, we found a dramatic reduction in testicular D-Asp levels, accompanied by a significant decrease in the serum testosterone levels and testicular 17β-HSD, the enzyme involved in testosterone biosynthesis. Additionally, in the testes of these Ddo knockin mice, the expression of PCNA and SYCP3 proteins decreased, suggesting alterations in spermatogenesis-related processes, as well as an increase in the cytosolic cytochrome c protein levels and TUNEL-positive cell number, which indicate an increase in apoptosis. To further investigate the histological and morphometric testicular alterations in Ddo knockin mice, we analyzed the expression and localization of prolyl endopeptidase (PREP) and disheveled-associated activator of morphogenesis 1 (DAAM1), two proteins involved in cytoskeletal organization. Our results showed that the testicular levels of DAAM1 and PREP in Ddo knockin mice were different from those in wild-type animals, suggesting that the deficiency of D-Asp is associated with overall cytoskeletal disorganization. Our findings confirmed that physiological D-Asp influences testosterone biosynthesis and plays a crucial role in germ cell proliferation and differentiation, which are required for successful reproduction.
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Chieffi Baccari G, Falvo S, Santillo A, Di Giacomo Russo F, Di Fiore MM. D-Amino acids in mammalian endocrine tissues. Amino Acids 2020; 52:1263-1273. [PMID: 32930873 DOI: 10.1007/s00726-020-02892-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/07/2020] [Indexed: 01/05/2023]
Abstract
D-Aspartate, D-serine and D-alanine are a regular occurrence in mammalian endocrine tissues, though in amounts varying with the type of gland. The pituitary gland, pineal gland, thyroid, adrenal glands and testis contain relatively large amounts of D-aspartate in all species examined. D-alanine is relatively abundant in the pituitary gland and pancreas. High levels of D-serine characterize the hypothalamus. D-leucine, D-proline and D-glutamate are generally low. The current knowledge of physiological roles of D-amino acids in endocrine tissues is far from exhaustive, yet the topic is attracting increasing interest because of its potential in pharmacological application. D-aspartate is known to act at all levels of the hypothalamus-pituitary-testis axis, playing a key role in reproductive biology in several vertebrate classes. An involvement of D-amino acids in the endocrine function of the pancreas is emerging. D-Aspartate has been immunolocalized in insulin-containing secretory granules in INS-1 E clonal β cells and is co-secreted with insulin by exocytosis. Specific immunolocalization of D-alanine in pituitary ACTH-secreting cells and pancreatic β-cells suggests that this amino acid participates in blood glucose regulation in mammals. By modulating insulin secretion, D-serine probably participates in the control of systemic glucose metabolism by modulating insulin secretion. We anticipate that future investigation will significantly increase the functional repertoire of D-amino acids in homeostatic control.
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Affiliation(s)
- Gabriella Chieffi Baccari
- Dip. Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania "Luigi Vanvitelli", Via Vivaldi, 43, 81100, Caserta, Italy
| | - Sara Falvo
- Dip. Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania "Luigi Vanvitelli", Via Vivaldi, 43, 81100, Caserta, Italy
| | - Alessandra Santillo
- Dip. Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania "Luigi Vanvitelli", Via Vivaldi, 43, 81100, Caserta, Italy
| | - Federica Di Giacomo Russo
- Dip. Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania "Luigi Vanvitelli", Via Vivaldi, 43, 81100, Caserta, Italy
| | - Maria Maddalena Di Fiore
- Dip. Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania "Luigi Vanvitelli", Via Vivaldi, 43, 81100, Caserta, Italy.
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Murgia F, Corda V, Serrenti M, Usai V, Santoru ML, Hurt KJ, Passaretti M, Monni MC, Atzori L, Monni G. Seminal Fluid Metabolomic Markers of Oligozoospermic Infertility in Humans. Metabolites 2020; 10:metabo10020064. [PMID: 32053951 PMCID: PMC7074256 DOI: 10.3390/metabo10020064] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/05/2020] [Accepted: 02/07/2020] [Indexed: 12/16/2022] Open
Abstract
Infertility affects 12–15% of couples worldwide, and male factors are the cause of nearly half of all cases. Studying seminal fluid composition could lead to additional diagnostic accuracy and a better understanding of the pathophysiology of male factor infertility. Metabolomics offers a new opportunity to evaluate biomarkers and better understand pathological mechanisms. The aim of the study was to identify new markers or therapeutic targets to improve outcomes in male factor or idiopathic infertility patients. Semen samples were obtained from 29 men with a normal spermogram test, and from 18 oligozoospermic men. Samples were processed and analyzed by Nuclear Magnetic Resonance spectroscopy and, subsequently, multivariate and univariate statistical analyses. Receiving Operator Curves (ROC) and Spearman correlations were also performed. An Orthogonal Partial Least Square Discriminant Analysis supervised multivariate model was devised to compare the groups. The levels of fructose, myo-inositol, aspartate and choline were altered. Moreover, Spearman Correlation associated fructose, aspartate and myo-inositol with the total amount of spermatozoa, total motile spermatozoa, % of immotility and % of “in situ” spermatozoic motility respectively. NMR-based metabolomics allowed the identification of a specific metabolic fingerprint of the seminal fluids of patients affected by oligozoospermia.
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Affiliation(s)
- Federica Murgia
- Clinical Metabolomics Unit, Department of Biomedical Sciences, University of Cagliari, 09121 Cagliari, Italy; (F.M.); (M.L.S.); (M.P.); (L.A.)
| | - Valentina Corda
- Department of Prenatal and Preimplantation Genetic Diagnosis and Fetal Therapy, Ospedale Pediatrico Microcitemico “A.Cao”, 09121 Cagliari, Italy; (V.C.); (M.S.); (V.U.); (M.C.M.)
| | - Marianna Serrenti
- Department of Prenatal and Preimplantation Genetic Diagnosis and Fetal Therapy, Ospedale Pediatrico Microcitemico “A.Cao”, 09121 Cagliari, Italy; (V.C.); (M.S.); (V.U.); (M.C.M.)
| | - Valeria Usai
- Department of Prenatal and Preimplantation Genetic Diagnosis and Fetal Therapy, Ospedale Pediatrico Microcitemico “A.Cao”, 09121 Cagliari, Italy; (V.C.); (M.S.); (V.U.); (M.C.M.)
| | - Maria Laura Santoru
- Clinical Metabolomics Unit, Department of Biomedical Sciences, University of Cagliari, 09121 Cagliari, Italy; (F.M.); (M.L.S.); (M.P.); (L.A.)
| | - K. Joseph Hurt
- Divisions of Maternal Fetal Medicine and Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Mauro Passaretti
- Clinical Metabolomics Unit, Department of Biomedical Sciences, University of Cagliari, 09121 Cagliari, Italy; (F.M.); (M.L.S.); (M.P.); (L.A.)
| | - Maria Carla Monni
- Department of Prenatal and Preimplantation Genetic Diagnosis and Fetal Therapy, Ospedale Pediatrico Microcitemico “A.Cao”, 09121 Cagliari, Italy; (V.C.); (M.S.); (V.U.); (M.C.M.)
| | - Luigi Atzori
- Clinical Metabolomics Unit, Department of Biomedical Sciences, University of Cagliari, 09121 Cagliari, Italy; (F.M.); (M.L.S.); (M.P.); (L.A.)
| | - Giovanni Monni
- Department of Prenatal and Preimplantation Genetic Diagnosis and Fetal Therapy, Ospedale Pediatrico Microcitemico “A.Cao”, 09121 Cagliari, Italy; (V.C.); (M.S.); (V.U.); (M.C.M.)
- Correspondence:
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Di Fiore MM, Boni R, Santillo A, Falvo S, Gallo A, Esposito S, Baccari GC. D-Aspartic Acid in Vertebrate Reproduction: Animal Models and Experimental Designs ‡. Biomolecules 2019; 9:biom9090445. [PMID: 31484465 PMCID: PMC6770039 DOI: 10.3390/biom9090445] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/29/2019] [Accepted: 09/02/2019] [Indexed: 11/16/2022] Open
Abstract
This article reviews the animal models and experimental designs that have been used during the past twenty years to demonstrate the prominent role played by d-aspartate (d-Asp) in the reproduction of vertebrates, from amphibians to humans. We have tabulated the findings of in vivo and in vitro experiments that demonstrate the effects of d-Asp uptake on hormone production and gametogenesis in vertebrate animal models. The contribution of each animal model to the existing knowledge on the role of d-Asp in reproductive processes has been discussed. A critical analysis of experimental designs has also been carried out. Experiments performed on wild animal species suggest a role of d-Asp in the mechanisms that regulate the reproductive cycle. Several in vivo and in vitro studies carried out on mouse and rat models have facilitated an understanding of the molecular pathways activated by D-Asp in both steroidogenesis and spermatogenesis, with particular emphasis on testosterone biosynthesis. Some attempts using d-Asp for the improvement of reproductive activity in animals of commercial interest have yielded mixed results. The increased transcriptome activity of enzymes and receptors involved in the reproductive activity in d-Asp-treated broiler roosters revealed further details on the mechanism of action of d-Asp on the reproductive processes. The close relationship between d-Asp and reproductive activity has emerged, particularly in relation to its effects exerted on semen quality, proposing therapeutic applications of this amino acid in andrology and in medically-assisted procreation techniques.
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Affiliation(s)
- Maria Maddalena Di Fiore
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Raffaele Boni
- Dipartimento di Scienze, Università della Basilicata, Via dell'Ateneo Lucano 10, 85100 Potenza, Italy
| | - Alessandra Santillo
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy.
| | - Sara Falvo
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Alessandra Gallo
- Dipartimento di Biologia ed Evoluzione degli Organismi Marini, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
| | - Sabrina Esposito
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Gabriella Chieffi Baccari
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
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Santillo A, Falvo S, Di Fiore MM, Di Giacomo Russo F, Chieffi P, Usiello A, Pinelli C, Baccari GC. AMPA receptor expression in mouse testis and spermatogonial GC-1 cells: A study on its regulation by excitatory amino acids. J Cell Biochem 2019; 120:11044-11055. [PMID: 30762900 DOI: 10.1002/jcb.28382] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 12/20/2018] [Accepted: 01/07/2019] [Indexed: 01/24/2023]
Abstract
Excitatory amino acids (EAAs) are found present in the nervous and reproductive systems of animals. Numerous studies have demonstrated a regulatory role for Glutamate (Glu), d-aspartate ( d-Asp) and N-methyl- d-aspartate (NMDA) in the control of spermatogenesis. EAAs are able to stimulate the Glutamate receptors, including the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR). Here in, we assess expression of the main AMPAR subunits, GluA1 and GluA2/3, in the mouse testis and in spermatogonial GC-1 cells. The results showed that both GluA1 and GluA2/3 were localized in mouse testis prevalently in spermatogonia. The subunit GluA2/3 was more highly expressed compared with GluA1 in both the testis and the GC-1 cells. Subsequently, GC-1 cells were incubated with medium containing l-Glu, d-Glu, d-Asp or NMDA to determine GluA1 and GluA2/3 expressions. At 30 minutes and 2 hours of incubation, EAA-treated GC-1 cells showed significantly higher expression levels of both GluA1 and GluA2/3. Furthermore, p-extracellular signal-regulated kinase (ERK), p-Akt, proliferating cell nuclear antigen (PCNA), and Aurora B expressions were assayed in l-Glu-, d-Glu-, and NMDA-treated GC-1 cells. At 30 minutes and 2 hours of incubation, treated GC-1 cells showed significantly higher expression levels of p-ERK and p-Akt. A consequent increase of PCNA and Aurora B expressions was induced by l-Glu and NMDA, but not by d-Glu. Our study demonstrates a direct effect of the EAAs on spermatogonial activity. In addition, the increased protein expression levels of GluA1 and GluA2/3 in EAA-treated GC-1 cells suggest that EAAs could activate ERK and Akt pathways through the AMPAR. Finally, the increased PCNA and Aurora B levels may imply an enhanced proliferative activity.
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Affiliation(s)
- Alessandra Santillo
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Sara Falvo
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Maria M Di Fiore
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Federica Di Giacomo Russo
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Paolo Chieffi
- Department of Psychology, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Alessandro Usiello
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Claudia Pinelli
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Gabriella Chieffi Baccari
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
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Biaryl axially chiral derivatizing agent for simultaneous separation and sensitive detection of proteinogenic amino acid enantiomers using liquid chromatography–tandem mass spectrometry. J Chromatogr A 2019; 1593:91-101. [DOI: 10.1016/j.chroma.2019.01.075] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 01/26/2019] [Accepted: 01/29/2019] [Indexed: 02/07/2023]
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Raspa M, Mahabir E, Paoletti R, Protti M, Mercolini L, Schiller P, Scavizzi F. Effects of oral d-aspartate on sperm quality in B6N mice. Theriogenology 2018; 121:53-61. [DOI: 10.1016/j.theriogenology.2018.07.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 07/30/2018] [Accepted: 07/30/2018] [Indexed: 11/16/2022]
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Di Fiore MM, Santillo A, Falvo S, Chieffi Baccari G, Venditti M, Di Giacomo Russo F, Lispi M, D'Aniello A. Sex hormone levels in the brain of d-aspartate-treated rats. C R Biol 2017; 341:9-15. [PMID: 29203165 DOI: 10.1016/j.crvi.2017.11.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 11/13/2017] [Accepted: 11/13/2017] [Indexed: 10/18/2022]
Abstract
d-Aspartate (d-Asp) is an endogenous amino acid present in the central nervous system and endocrine glands of various animal taxa. d-Asp is implicated in neurotransmission, physiology of learning, and memory processes. In gonads, it plays a crucial role in sex hormone synthesis. We have investigated the effects of chronic (30 days d-Asp drinking solution) and acute (i.p. injection of 2μmol/g bw d-Asp) treatments on sex steroid synthesis in rat brain. Furthermore, to verify the direct effect of d-Asp on neurosteroidogenic enzyme activities, brain homogenates were incubated with different substrates (cholesterol, progesterone, or testosterone) with or without the addition of d-Asp. Enzyme activities were measured by evaluating the in vitro conversion rate of (i) cholesterol to progesterone, testosterone, and 17β-estradiol, (ii) progesterone to testosterone and 17β-estradiol, (iii) testosterone to 17β-estradiol. We found that d-Asp oral administration produced an increase of approximately 40% in progesterone, 110% in testosterone, and 35% in 17β-estradiol. Similarly, the results of the acute experiment showed that at 30min after d-Asp treatment, the progesterone, testosterone, and 17β-estradiol levels increased by 29-35%, and at 8h they further increased by a 100% increment. In vitro experiments demonstrate that the addition of d-Asp to brain homogenate+substrate induces a significant increase in progesterone, testosterone and 17β-estradiol suggesting that the amino acid upregulates the local activity of steroidogenic enzymes.
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Affiliation(s)
- Maria Maddalena Di Fiore
- Dipartimento di Scienze e Tecnologie ambientali, biologiche e farmaceutiche, Università della Campania "Luigi Vanvitelli", via Vivaldi 43, 81100 Caserta, Italy
| | - Alessandra Santillo
- Dipartimento di Scienze e Tecnologie ambientali, biologiche e farmaceutiche, Università della Campania "Luigi Vanvitelli", via Vivaldi 43, 81100 Caserta, Italy.
| | - Sara Falvo
- Dipartimento di Scienze e Tecnologie ambientali, biologiche e farmaceutiche, Università della Campania "Luigi Vanvitelli", via Vivaldi 43, 81100 Caserta, Italy
| | - Gabriella Chieffi Baccari
- Dipartimento di Scienze e Tecnologie ambientali, biologiche e farmaceutiche, Università della Campania "Luigi Vanvitelli", via Vivaldi 43, 81100 Caserta, Italy
| | - Massimo Venditti
- Dipartimento di Medicina Sperimentale, Università della Campania "Luigi Vanvitelli", Naples, Italy
| | - Federica Di Giacomo Russo
- Dipartimento di Scienze e Tecnologie ambientali, biologiche e farmaceutiche, Università della Campania "Luigi Vanvitelli", via Vivaldi 43, 81100 Caserta, Italy
| | - Monica Lispi
- Medical Affair Department Fertility TA, Merck-Serono SAS, Rome, Italy
| | - Antimo D'Aniello
- Dipartimento di Scienze e Tecnologie ambientali, biologiche e farmaceutiche, Università della Campania "Luigi Vanvitelli", via Vivaldi 43, 81100 Caserta, Italy; Department of Neurobiology and Comparative Physiology, Zoological Station "Anthon Dohrn", Naples, Italy.
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12
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Improvement of post-thawed sperm quality and fertility of Arian rooster by oral administration of d-aspartic acid. Theriogenology 2017; 92:69-74. [DOI: 10.1016/j.theriogenology.2017.01.014] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 01/06/2017] [Accepted: 01/06/2017] [Indexed: 11/22/2022]
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13
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Molecular Mechanisms Elicited by d-Aspartate in Leydig Cells and Spermatogonia. Int J Mol Sci 2016; 17:ijms17071127. [PMID: 27428949 PMCID: PMC4964501 DOI: 10.3390/ijms17071127] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 07/08/2016] [Accepted: 07/08/2016] [Indexed: 12/11/2022] Open
Abstract
A bulk of evidence suggests that d-aspartate (d-Asp) regulates steroidogenesis and spermatogenesis in vertebrate testes. This review article focuses on intracellular signaling mechanisms elicited by d-Asp possibly via binding to the N-methyl-d-aspartate receptor (NMDAR) in both Leydig cells, and spermatogonia. In Leydig cells, the amino acid upregulates androgen production by eliciting the adenylate cyclase-cAMP and/or mitogen-activated protein kinase (MAPK) pathways. d-Asp treatment enhances gene and protein expression of enzymes involved in the steroidogenic cascade. d-Asp also directly affects spermatogonial mitotic activity. In spermatogonial GC-1 cells, d-Asp induces phosphorylation of MAPK and AKT serine-threonine kinase proteins, and stimulates expression of proliferating cell nuclear antigen (PCNA) and aurora kinase B (AURKB). Further stimulation of spermatogonial GC-1 cell proliferation might come from estradiol/estrogen receptor β (ESR2) interaction. d-Asp modulates androgen and estrogen levels as well as the expression of their receptors in the rat epididymis by acting on mRNA levels of Srd5a1 and Cyp19a1 enzymes, hence suggesting involvement in spermatozoa maturation.
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Zhang J, Huang Z, Chen M, Xia Y, Martin FL, Hang W, Shen H. Urinary metabolome identifies signatures of oligozoospermic infertile men. Fertil Steril 2014; 102:44-53.e12. [PMID: 24746742 DOI: 10.1016/j.fertnstert.2014.03.033] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 02/11/2014] [Accepted: 03/18/2014] [Indexed: 10/25/2022]
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15
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Raucci F, D'Aniello A, Di Fiore MM. Stimulation of androgen production by D-aspartate through the enhancement of StAR, P450scc and 3β-HSD mRNA levels in vivo rat testis and in culture of immature rat Leydig cells. Steroids 2014; 84:103-10. [PMID: 24713504 DOI: 10.1016/j.steroids.2014.03.016] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 03/18/2014] [Accepted: 03/25/2014] [Indexed: 11/23/2022]
Abstract
Previous studies have shown a role of d-aspartic acid (d-Asp) in testicular steroidogenesis. Here, we evaluated the effects of d-Asp on androgen production and on expression levels of mRNAs encoding specific steroidogenic key molecules. d-Asp was endogenously present in adult rat testis and its content paralleled to serum luteinizing hormone (LH) and, local and circulating androstenedione and testosterone levels. In vivod-Asp administration induced serum LH release, causing an indirect increase of androstenedione and testosterone levels by enhancing steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc) and 3β-hydroxysteroid dehydrogenase/D5-D4 isomerases (3β-HSD) mRNA levels. The direct endocrine role of d-Asp was evaluated using cultured immature Leydig cells (ILCs) obtained from 35days old rats. Cytoplasm and nucleus of ILCs localized d-Asp, while StAR marked the cytoplasm only. After 12h from d-Asp in vitro administration, ILCs resulted intensely d-Asp stained, and StaR protein level, evaluated by Western blotting, significantly increased. After 24h, significant androstenedione and testosterone syntheses were induced. At molecular level, d-Asp administration significantly increased StAR, P450scc and 3β-HSD mRNAs at 2, 4 and 12h, respectively. The temporal shift on relative mRNA expression levels indicated that d-Asp exerted its physiological role through sequential gene cascade activation of those molecules implicated in the synthesis of androgens. Conclusively, our findings demonstrated that d-Asp is a local messenger in testis and give a contribution in understanding the complexity of local endocrine regulation as well as the molecular events leading the acquisition to a steroidogenic competence by ILCs.
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Affiliation(s)
- Franca Raucci
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Via Vivaldi 43, 81100 Caserta, Italy.
| | - Antimo D'Aniello
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Maria Maddalena Di Fiore
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Via Vivaldi 43, 81100 Caserta, Italy
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16
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Current knowledge of d-aspartate in glandular tissues. Amino Acids 2014; 46:1805-18. [DOI: 10.1007/s00726-014-1759-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 04/28/2014] [Indexed: 12/24/2022]
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17
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Santillo A, Falvo S, Chieffi P, Burrone L, Chieffi Baccari G, Longobardi S, Di Fiore MM. d-aspartate affects NMDA receptor-extracellular signal–regulated kinase pathway and upregulates androgen receptor expression in the rat testis. Theriogenology 2014; 81:744-51. [DOI: 10.1016/j.theriogenology.2013.12.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 11/28/2013] [Accepted: 12/09/2013] [Indexed: 10/25/2022]
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18
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Raucci F, Di Fiore MM. The maturation of oocyte follicular epithelium of Podarcis s. sicula is promoted by D-aspartic acid. J Histochem Cytochem 2013; 58:157-71. [PMID: 19826072 DOI: 10.1369/jhc.2009.954636] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Accepted: 09/25/2009] [Indexed: 11/22/2022] Open
Abstract
We investigated whether the maturation of oocyte follicular epithelium of lizard is affected by d-aspartic acid (d-Asp). Our results demonstrated that d-Asp is endogenously present in the oocytes, and its distribution varies during the reproductive cycle and following intraperitoneal administration. At previtellogenesis, it is observed in the cytoplasm and nucleus of pyriform cells, in intermediate cells, in some small cells of the granulosa, in the ooplasm, and in some thecal elements. At vitellogenesis, d-Asp is localized in the proximity of the zona pellucida, in the theca, and in the ooplasm. Injected d-Asp is mainly captured by pyriform cells and ooplasm of previtellogenic oocytes, but a moderate accumulation is evident in the cytoplasm of some small granulosa cells and in the theca. d-Asp also increases the ovarian and plasmatic levels of 17β-estradiol and decreases those of testosterone. As a direct and/or indirect consequence of d-Asp, previtellogenic oocytes grow up and mature, resulting in a higher accumulation of carbohydrates in the granulosa, zona pellucida, and ooplasm, but also a reduction in the thickness of the granulosa layer and an increase of the theca stratum. Taken together, our results show that d-Asp may be related to the synchrony of reproduction, either enhancing the growth and maturation of follicular epithelium or influencing its endocrine functions.
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Affiliation(s)
- Franca Raucci
- Department of Life Sciences, Second University of Naples, Caserta, Italy.
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Santillo A, Pinelli C, Burrone L, Chieffi Baccari G, Di Fiore MM. D-Aspartic acid implication in the modulation of frog brain sex steroid levels. Gen Comp Endocrinol 2013; 181:72-6. [PMID: 23153651 DOI: 10.1016/j.ygcen.2012.11.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 10/26/2012] [Accepted: 11/02/2012] [Indexed: 10/27/2022]
Abstract
There is evidence that D-aspartate (D-Asp) modulates sex hormone levels in frog testis by regulating the activity of P450 aromatase (P450 aro), the key enzyme which converts Testosterone (T) in 17ß-Estradiol (E2). Here we report, for the first time, that there is a direct correlation among brain levels of D-Asp, P450 aro, E2 and Estradiol Receptor (ERα) in the male frogs during the reproductive as well as the post-reproductive phases of the breeding cycle, with highest levels being observed in the post-reproductive period. D-Asp i.p. administration to frogs ready for reproduction, induced an increase of brain P450 aro protein expression with concomitant enhancement of both E2 levels and ERα expression; at the same time, brain T levels and Androgen receptor expression decreased. In contrast, in the post-reproductive frogs, D-Asp treatment did not modify any of these parameters. Taken together, these results imply that the regulation of P450 aro expression by D-Asp could be an important step in the control of E2 levels in the frog brain.
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Affiliation(s)
- Alessandra Santillo
- Dipartimento di Scienze della Vita, Seconda Università di Napoli, Via Vivaldi 43, 81100 Caserta, Italy
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20
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D’Aniello G, Ronsini S, Notari T, Grieco N, Infante V, D’Angel N, Mascia F, Fiore MMD, Fisher G, D’Aniello A. D-Aspartate, a Key Element for the Improvement of Sperm Quality. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/asm.2012.24008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Burrone L, Raucci F, Di Fiore MM. Steroidogenic gene expression following D-aspartate treatment in frog testis. Gen Comp Endocrinol 2012; 175:109-17. [PMID: 22036840 DOI: 10.1016/j.ygcen.2011.10.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 10/09/2011] [Accepted: 10/11/2011] [Indexed: 11/30/2022]
Abstract
Previous studies have provided evidence that D-Asp plays a role in steroid-mediated reproductive biology in amphibians, reptiles, birds and mammals. To examine the molecular involvement of D-Asp on steroidogenic pathway regulation, we analysed the expression of StAR, P450 aromatase and 5αRed2 mRNAs in Pelophylax esculentus testis, either in relation to the reproductive cycle or D-Asp treatment. Basal StAR mRNA levels, as well as D-Asp and testosterone concentrations, were higher in reproductive than in post-reproductive frogs. D-Asp treatment increased StAR mRNA expression and immunolocalisation in both the reproductive and post-reproductive periods. In control testis, aromatase mRNA levels were higher in the post-reproductive period, but following D-Asp administration, they increased only in the reproductive period. The level of 5αRed2 mRNA was higher in reproductive frogs than in post-reproductive frogs, and it increased after D-Asp treatment only in the post-reproductive phase. Our results suggest that, in P. esculentus testis, D-Asp increases StAR mRNA in both periods, and P450 aromatase and 5αRed2 mRNAs at different points during the reproductive cycle.
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Affiliation(s)
- Lavinia Burrone
- Dipartimento di Scienze della Vita, Second University of Naples, Via Vivaldi 43, 81100 Caserta, Italy
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22
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Han H, Miyoshi Y, Oyama T, Konishi R, Mita M, Hamase K. Enantioselective micro-2D-HPLC determination of aspartic acid in the pineal glands of rodents with various melatonin contents. J Sep Sci 2011; 34:2847-53. [DOI: 10.1002/jssc.201100609] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 08/10/2011] [Accepted: 08/11/2011] [Indexed: 12/23/2022]
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23
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Visser WF, Verhoeven-Duif NM, Ophoff R, Bakker S, Klomp LW, Berger R, de Koning TJ. A sensitive and simple ultra-high-performance-liquid chromatography-tandem mass spectrometry based method for the quantification of D-amino acids in body fluids. J Chromatogr A 2011; 1218:7130-6. [PMID: 21890145 DOI: 10.1016/j.chroma.2011.07.087] [Citation(s) in RCA: 121] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 07/25/2011] [Accepted: 07/26/2011] [Indexed: 10/17/2022]
Abstract
D-Amino acids are increasingly being recognized as important signaling molecules in mammals, including humans. D-Serine and D-aspartate are believed to act as signaling molecules in the central nervous system. Interestingly, several other D-amino acids also occur in human plasma, but very little is currently known regarding their function and origin. Abnormal levels of D-amino acids have been implicated in the pathogenesis of different diseases, including schizophrenia and amyotrophic lateral sclerosis (ALS), indicating that D-amino acid levels hold potential as diagnostic markers. Research into the biological functions of D-amino acids is hindered, however, by the lack of sufficiently sensitive, high-throughput analytical methods. In particular, the interference of large amounts of L-amino acids in biological samples and the low concentrations of D-amino acids are challenging. In this paper, we compared 7 different chiral derivatization agents for the analysis of D-amino acids and show that the chiral reagent (S)-NIFE offers outstanding performance in terms of sensitivity and enantioselectivity. An UPLC-MS/MS based method for the quantification of D-amino acids human biological fluids was then developed using (S)-NIFE. Baseline separation (R(s)>2.45) was achieved for the isomers of all 19 chiral proteinogenic amino acids. The limit of detection was <1 nM for all amino acids except d-alanine (1.98 nM), d-methionine (1.18 nM) and d-asparagine (5.15 nM). For measurements in human plasma, cerebrospinal fluid and urine, the accuracy ranged between 85% and 107%. The intra-assay and inter-assay were both <16% RSD for these three different matrices. Importantly, the method does not suffer from spontaneous racemization during sample preparation and derivatization. Using the described method, D-amino acid levels in human cerebrospinal fluid, plasma and urine were measured.
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Affiliation(s)
- Wouter F Visser
- University Medical Center Utrecht/Wilhelmina Children's Hospital, Department of Metabolic and Endocrine Diseases, Utrecht, The Netherlands
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24
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Raucci F, Di Fiore MM. D-Asp: a new player in reproductive endocrinology of the amphibian Rana esculenta. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 879:3268-76. [PMID: 21531634 DOI: 10.1016/j.jchromb.2011.04.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 03/24/2011] [Accepted: 04/01/2011] [Indexed: 11/18/2022]
Abstract
We investigated the involvement of D-Aspartic acid (D-Asp) on ovarian and testicular morphology of the green frog, Rana esculenta, and its effect on the testosterone production. The study has been performed throughout the reproductive cycle. In both ovary and testis a substantial amount of D-Asp is endogenously present and its concentration varies as function of reproduction. In the frog, D-Asp content is differently correlated with gonadal and plasmatic levels of testosterone, depending on the sex. In fact, the amount of the D-Asp is inversely linked with that of the testosterone in the ovary, while this correlation directly matched in the testis. In vivo short-term experiments, consisting of a single intra-peritoneal injection of D-Asp (2.0 μmol/g body weight), demonstrated that the enantiomer is significantly accumulated by both the ovary and testis, reaching after 3 h the highest uptake and thereafter decreasing to baseline values within 24 h. Furthermore, D-Asp influences the synthesis and/or the release of testosterone, causing a decrease of its level in the female, and an increase in the male, respectively. In vivo long-term experiments, D-Asp, chronically administered to the frogs of both sexes, enhances the maturation of both gonads, determining in the oocytes an higher accumulation of carbohydrate yolk plates in the ooplasm, and stimulating the spermatogenesis in the testis. Taken altogether, our results show that D-Asp operates differently in female and male frog gonads, indicating that it has different targets in the reproductive machinery depending on the sex.
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Affiliation(s)
- Franca Raucci
- Department of Life Sciences, Second University of Naples (SUN), Via Vivaldi 43, 81100 Caserta, Italy
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25
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Katane M, Homma H. D-Aspartate--an important bioactive substance in mammals: a review from an analytical and biological point of view. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 879:3108-21. [PMID: 21524944 DOI: 10.1016/j.jchromb.2011.03.062] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 03/23/2011] [Accepted: 03/30/2011] [Indexed: 01/08/2023]
Abstract
It was long believed that D-amino acids were either unnatural isomers or laboratorial artifacts and that the important functions of amino acids were exerted only by l-amino acids. However, recent investigations have shown that a variety of D-amino acids are present in mammals and that they play important roles in physiological functions in the body. Among the free d-amino acids that have been identified in mammals, D-aspartate (D-Asp) has been shown to play a crucial role in the neuroendocrine and endocrine systems as well as in the central nervous system. Here, we present an overview of recent studies of free D-Asp, focusing on the analytical methods in real biological matrices, expression and localization in tissues and cells, biological and physiological activities, biosynthesis, degradation, cellular transport, and possible relevance to disease. In addition to frequently used techniques for the enantiomeric determination of amino acids, including high-performance liquid chromatography and enzymatic methods, the recent development of analytical methods is also described.
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Affiliation(s)
- Masumi Katane
- Laboratory of Biomolecular Science, Department of Pharmaceutical Life Sciences, Kitasato University, 5-9-1 Shirokane, Tokyo 108-8641, Japan
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26
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D'Aniello S, Somorjai I, Garcia-Fernàndez J, Topo E, D'Aniello A. D-Aspartic acid is a novel endogenous neurotransmitter. FASEB J 2010; 25:1014-27. [PMID: 21163862 DOI: 10.1096/fj.10-168492] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
D-aspartic acid (D-Asp) is present in invertebrate and vertebrate neuroendocrine tissues, where it carries out important physiological functions and is implicated in nervous system development. We show here that D-Asp is a novel endogenous neurotransmitter in two distantly related animals, a mammal (Rattus norvegicus) and a mollusk (Loligo vulgaris). Our main findings demonstrate that D-Asp is present in high concentrations in the synaptic vesicles of axon terminals; synthesis for this amino acid occurs in neurons by conversion of L-Asp to D-Asp via D-aspartate racemase; depolarization of nerve endings with K(+) ions evokes an immediate release of D-Asp in a Ca(2+) dependent manner; specific receptors for D-Asp occur at the postsynaptic membrane, as demonstrated by binding assays and by the expansion of squid skin chromatophores; D-aspartate oxidase, the specific enzyme that oxidizes D-Asp, is present in the postsynaptic membranes; and stimulation of nerve endings with D-Asp triggers signal transduction by increasing the second messenger cAMP. Taken together, these data demonstrate that D-Asp fulfills all criteria necessary to be considered a novel endogenous neurotransmitter. Given its known role in neurogenesis, learning, and neuropathologies, our results have important implications for biomedical and clinical research.
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Affiliation(s)
- Salvatore D'Aniello
- Departament de Genètica, Institut de Biomedicina, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
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27
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Topo E, Fisher G, Sorricelli A, Errico F, Usiello A, D'Aniello A. Thyroid hormones and D-aspartic acid, D-aspartate oxidase, D-aspartate racemase, H2O2, and ROS in rats and mice. Chem Biodivers 2010; 7:1467-78. [PMID: 20564565 DOI: 10.1002/cbdv.200900360] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Total concentrations of thyroid hormones T(3) and T(4), and of their free forms, FT(3) and FT(4), D-aspartic acid (D-Asp), D-aspartate oxidase (D-AspO), D-aspartate racemase, H(2)O(2), and ROS (reactive oxygen species) were determined in rats and mice. T(3) and T(4) were 1 and 50 ng/ml, respectively, in serum, and 750 and 40000 ng/g, respectively, in thyroid. Concentrations of the free forms FT(3) and FT(4) were ca. 250 times lower than their respective total concentrations. The endogenous content of D-Asp in thyroid gland was ca. 100 nmol/g tissue, whereas the activity of D-AspO was ca. 80 units/mg thyroid, and that of D-aspartate racemase was ca. 15 units/mg thyroid. H(2)O(2) Concentration in rat and mouse thyroid gland was ca. 290 pmol/g thyroid, and the concentration of ROS was ca. 10 pmol/DCF/min/mg protein. H(2)O(2) is essential for the iodination of the tyrosyl residues to produce mono- and diiodotyrosine that are the precursors for the synthesis of T(3) and T(4). Production of H(2)O(2) in thyroid glands occurs by oxidation of endogenous D-Asp by D-AspO (D-Asp+O(2)+H(2)O-->alpha-oxaloacetate+NH(3)+H(2)O(2)). D-Aspartate racemase catalyzes the in vivo production of D-Asp from L-Asp. Thus, interaction of endogenous D-Asp, D-AspO, and D-aspartate racemase in thyroid gland constitutes an additional biochemical pathway for the production of H(2)O(2) and consequently for the synthesis of thyroid hormones.
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Affiliation(s)
- Enza Topo
- Laboratory of Animal Physiology and Evolution, Zoological Station Anton Dohrn, Villa Comunale, I-80121 Napoli, Italy
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28
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Mutaguchi Y, Ohmori T, Sakuraba H, Yoneda K, Doi K, Ohshima T. Visible wavelength spectrophotometric assays of L-aspartate and D-aspartate using hyperthermophilic enzyme systems. Anal Biochem 2010; 409:1-6. [PMID: 20951671 DOI: 10.1016/j.ab.2010.10.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Revised: 10/12/2010] [Accepted: 10/12/2010] [Indexed: 12/28/2022]
Abstract
Methods with which to simply and rapidly assay L-aspartate (L-Asp) and D-aspartate (D-Asp) would be highly useful for physiological research and for nutritional and clinical analyses. Levels of L- and D-Asp in food and cell extracts are currently determined using high-performance liquid chromatography. However, this method is time-consuming and expensive. Here we describe a simple and specific method for using an L-aspartate dehydrogenase (L-AspDH) system to colorimetrically assay L-Asp and a system of three hyperthermophilic enzymes--aspartate racemase (AspR), L-AspDH, and L-aspartate oxidase (L-AO)--to assay D-Asp. In the former, the reaction rate of nicotinamide adenine dinucleotide (NAD(+))-dependent L-AspDH was measured based on increases in the absorbance at 438 nm, reflecting formation of formazan from water-soluble tetrazolium-1 (WST-1), using 1-methoxy-5-methylphenazinum methyl sulfate (mPMS) as a redox mediator. In the latter, D-Asp was measured after first removing L-Asp in the sample solution with L-AO. The remaining D-Asp was then changed to L-Asp using racemase, and the newly formed L-Asp was assayed calorimetrically using NAD(+)-dependent aspartate dehydrogenase as described above. This method enables simple and rapid spectrophotometric determination of 1 to 100 μM L- and D-Asp in the assay systems. In addition, methods were applicable to the L- and D-Asp determinations in some living cells and foods.
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Affiliation(s)
- Yuta Mutaguchi
- Microbial Genetic Division, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
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29
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Friedman M. Origin, Microbiology, Nutrition, and Pharmacology of D-Amino Acids. Chem Biodivers 2010; 7:1491-530. [DOI: 10.1002/cbdv.200900225] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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30
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D-Aspartate Oxidase: The Sole Catabolic Enzyme Acting on Free D-Aspartate in Mammals. Chem Biodivers 2010; 7:1435-49. [DOI: 10.1002/cbdv.200900250] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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31
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Evidence for the involvement of d-aspartic acid in learning and memory of rat. Amino Acids 2009; 38:1561-9. [DOI: 10.1007/s00726-009-0369-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2009] [Accepted: 10/10/2009] [Indexed: 10/20/2022]
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32
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Topo E, Soricelli A, D'Aniello A, Ronsini S, D'Aniello G. The role and molecular mechanism of D-aspartic acid in the release and synthesis of LH and testosterone in humans and rats. Reprod Biol Endocrinol 2009; 7:120. [PMID: 19860889 PMCID: PMC2774316 DOI: 10.1186/1477-7827-7-120] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2009] [Accepted: 10/27/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND D-aspartic acid is an amino acid present in neuroendocrine tissues of invertebrates and vertebrates, including rats and humans. Here we investigated the effect of this amino acid on the release of LH and testosterone in the serum of humans and rats. Furthermore, we investigated the role of D-aspartate in the synthesis of LH and testosterone in the pituitary and testes of rats, and the molecular mechanisms by which this amino acid triggers its action. METHODS For humans: A group of 23 men were given a daily dose of D-aspartate (DADAVIT) for 12 days, whereas another group of 20 men were given a placebo. For rats: A group of 10 rats drank a solution of either 20 mM D-aspartate or a placebo for 12 days. Then LH and testosterone accumulation was determined in the serum and D-aspartate accumulation in tissues. The effects of D-aspartate on the synthesis of LH and testosterone were gauged on isolated rat pituitary and Leydig cells. Tissues were incubated with D-aspartate, and then the concentration (synthesis) of LH and cGMP in the pituitary and of testosterone and cAMP in the Leydig cells was determined. RESULTS In humans and rats, sodium D-aspartate induces an enhancement of LH and testosterone release. In the rat pituitary, sodium D-aspartate increases the release and synthesis of LH through the involvement of cGMP as a second messenger, whereas in rat testis Leydig cells, it increases the synthesis and release of testosterone and cAMP is implicated as second messenger. In the pituitary and in testes D-Asp is synthesized by a D-aspartate racemase which convert L-Asp into D-Asp. The pituitary and testes possesses a high capacity to trapping circulating D-Asp from hexogen or endogen sources. CONCLUSION D-aspartic acid is a physiological amino acid occurring principally in the pituitary gland and testes and has a role in the regulation of the release and synthesis of LH and testosterone in humans and rats.
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Affiliation(s)
- Enza Topo
- Stazione Zoologica Anton Dohrn, 80121, Villa Comunale, 80121, Napoli, Italy
| | - Andrea Soricelli
- Università di Napoli Parthenope e Fondazione IRCCS-SDN, Via Gianturco 113, 80143 Naples, Italy
| | - Antimo D'Aniello
- Stazione Zoologica Anton Dohrn, 80121, Villa Comunale, 80121, Napoli, Italy
| | - Salvatore Ronsini
- Department of Obstetrics and Gynecology, and Reproductive Medicine (IVF Unit), Hospital 'S Luca', 84078 Vallo della Lucania, Italy
| | - Gemma D'Aniello
- Department of Obstetrics and Gynecology, and Reproductive Medicine (IVF Unit), Hospital 'S Luca', 84078 Vallo della Lucania, Italy
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Macchia G, Topo E, Mangano N, D'Aniello E, Boni R. DL-Aspartic acid administration improves semen quality in rabbit bucks. Anim Reprod Sci 2009; 118:337-43. [PMID: 19716665 DOI: 10.1016/j.anireprosci.2009.07.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 07/07/2009] [Accepted: 07/20/2009] [Indexed: 01/08/2023]
Abstract
Recently, D-aspartic acid (d-Asp) has been suggested as being involved in mechanisms regulating reproduction activity in animals and human. In this study we analyzed the effects of DL-Asp oral administration on sperm production in the rabbit. Bucks from 60, bred in a genetic centre and used for semen production, were divided in 2 subgroups of 6 individuals. The treated group was fed with a concentrate containing DL-Asp which assured a daily administration of 1.3g dl-Asp/head; the control group was fed with the same concentrate without DL-Asp. The treatment was carried out for 2wk and animals were monitored weekly, from 1wk before the start of the treatment to 3wk after the end of the treatment. Through the experimental period there were no significant variations in semen volume between the two groups. A significant increase in both sperm concentration and kinetic parameters, i.e., the overall percentage of motile spermatozoa, the average path velocity, the percentage of progressively motile spermatozoa, etc., was found in the supplemented group. L-Asp values in blood serum and seminal plasma did not vary through the experimental period. D-Asp concentration in blood serum increased more than 4-fold than baseline (P<0.01) at the end of the treatment and was maintained at higher than baseline values for up to 3wk after the end of the treatment. D-Asp concentration in seminal plasma was higher than in blood serum before the start of the treatment (13.7+/-1.6nM vs 3.5+/-3.3nM; P<0.01) which suggests an elective storage of D-Asp in the male genital tract. Baseline values of d-Asp concentration in seminal plasma significantly increased following treatment and were back to initial values 1wk after the end of the treatment. In conclusion, DL-Asp administration improved sperm quality in bucks and the high D-Asp content in seminal plasma suggests a primary role for this D-amino acid in regulatory mechanisms of reproductive activity.
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Affiliation(s)
- G Macchia
- Dipartimento di Scienze delle Produzioni Animali, Università della Basilicata, 85100 Potenza, Italy
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Raucci F, Di Fiore MM. The reproductive activity in the testis of Podarcis s. sicula involves D-aspartic acid: a study on c-kit receptor protein, tyrosine kinase activity and PCNA protein during annual sexual cycle. Gen Comp Endocrinol 2009; 161:373-83. [PMID: 19523373 DOI: 10.1016/j.ygcen.2009.02.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Revised: 01/26/2009] [Accepted: 02/02/2009] [Indexed: 11/21/2022]
Abstract
The current study provides substantial evidence that the pattern of synthesis of D-aspartic acid (D-Asp) in the testes of lizard Podarcis s. sicula throughout the reproductive cycle is in parallel with seasonal variations of testosterone, c-kit receptor protein, tyrosine kinase activity, and proliferating cell nuclear antigen (PCNA) protein. Although the trend is the same in all phases of the sexual cycle, the peaks of these three molecules are detectable only during the reproductive period. Using Western blot technique, we demonstrated that both polyclonal c-kit and PCNA antibodies specifically recognized bands with molecular mass of approximately 150 and approximately 36 kDa, respectively. By immunocytochemical methods, D-Asp immunopositivity appeared spread in the germinal epithelium as well as in the interstitial compartment of the testes. We also found specific c-kit labeling in I and II spermatogonia (SPG), in I and II spermatocytes (SPC), in the elongated spermatides, in spermatozoa, in Sertoli and Leydig cells. Like c-kit, PCNA positivity was located in the germinal epithelium pattern. Furthermore, we investigated the relationship between testosterone, c-kit receptor, tyrosine kinases activity and PCNA following treatment with D-Asp. In vivo experiments, entailing a single injection of D-Asp (2.0 micromol/g body weight), demonstrated that this amino acid significantly accumulated in the testes. After 3 h, its uptake was accompanied by an increase in testosterone levels and in the expression and intensity of immunostaining of c-kit receptor protein. Furthermore, at 6 h, exogenous D-Asp affected the phosphorylation of tyrosine kinases, whose activation was positively correlated with the temporal uptake of both D-Asp and testosterone detected in the testes. Thereafter, between 6 and 15 h, the expression of PCNA was induced and an increase in its immunolabeling intensity was observed. Taken all together, these results provide new insights into the testicular activity during the reproductive cycle of Podarcis s. sicula, suggesting that a sequential cascade of a functional relationship between testosterone levels, c-kit receptor protein, tyrosine kinase activity and PCNA could be partly mediated by D-aspartic acid.
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Affiliation(s)
- Franca Raucci
- Department of Life Sciences, Second University of Naples, Via Vivaldi 43, 81100 Caserta, Italy.
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Chandrashekar KN. D-Aspartic acid induced oxidative stress and mitochondrial dysfunctions in testis of prepubertal rats. Amino Acids 2009; 38:817-27. [PMID: 19381779 DOI: 10.1007/s00726-009-0288-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2008] [Accepted: 03/30/2009] [Indexed: 12/23/2022]
Abstract
Previously we demonstrated the potential of D-aspartic acid (D-Asp), an acidic amino acid to induce oxidative response in prepubertal rat testis in vitro. In the present study, we determined the extent of oxidative stress in the testis of prepubertal rats that were administered D-Asp (100 and 500 mg/kg bw/d, i.p. 7 days). D-Asp treatment significantly elevated the levels of reactive oxygen species, malondialdehyde and hydroperoxide in cytosol and mitochondria of testis, which were accompanied by enhanced glutathione levels, elevated activities of glutathione-dependent enzymes and catalase suggesting a state of oxidative stress. Further, the activities of D-aspartate oxidase and 3beta-hydroxy steroid dehydrogenase were elevated in the testis. The testis mitochondria of D-Asp-treated rats showed altered citric acid and complex enzyme activities, reduction in membrane potential, increased permeability and intracellular Ca(2+) levels. Collectively, these findings suggest the potential of D-Asp to induce oxidative perturbations in the testis of prepubertal rats and this mechanism may in part be responsible for the observed physiological effects.
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Affiliation(s)
- K N Chandrashekar
- Department of Biochemistry & Nutrition, Central Food Technological Research Institute (Council of Scientific and Industrial Research), Mysore 570020, India
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Di Fiore MM, Lamanna C, Assisi L, Botte V. Opposing effects of D-aspartic acid and nitric oxide on tuning of testosterone production in mallard testis during the reproductive cycle. Reprod Biol Endocrinol 2008; 6:28. [PMID: 18601714 PMCID: PMC2474629 DOI: 10.1186/1477-7827-6-28] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Accepted: 07/04/2008] [Indexed: 11/10/2022] Open
Abstract
UNLABELLED D-Aspartic acid (D-Asp) and nitric oxide (NO) play an important role in tuning testosterone production in the gonads of male vertebrates. In particular, D-Asp promotes either the synthesis or the release of testosterone, whereas NO inhibits it. In this study, we have investigated for the first time in birds the putative effects of D-Asp and NO on testicular testosterone production in relation to two phases of the reproductive cycle of the adult captive wild-strain mallard (Anas platyrhynchos) drake. It is a typical seasonal breeder and its cycle consists of a short reproductive period (RP) in the spring (April-May) and a non reproductive period (NRP) in the summer (July), a time when the gonads are quiescent. The presence and the localization of D-Asp and NO in the testis and the trends of D-Asp, NO and testosterone levels were assessed during the main phases of the bird's reproductive cycle. Furthermore, in vitro experiments revealed the direct effect of exogenously administered D-Asp and NO on testosterone steroidogenesis. METHODS By using immunohistochemical (IHC) techniques, we studied the presence and the distributional pattern of D-Asp and NO in the testes of RP and NRP drakes. D-Asp levels were evaluated by an enzymatic method, whereas NO content, via nitrite, was assessed using biochemical measurements. Finally, immunoenzymatic techniques determined testicular testosterone levels. RESULTS IHC analyses revealed the presence of D-Asp and NO in Leydig cells. The distributional pattern of both molecules was in some way correlated to the steroidogenic pathway, which is involved in autocrine testosterone production. Indeed, whereas NO was present only during the NRP, D-Asp was almost exclusively present during the RP. Consistently, the high testosterone testicular content occurring during RP was coupled to a high D-Asp level and a low NO content in the gonad. By contrast, in sexually inactive drakes (NRP), the low testosterone content in the gonad was coupled to a low D-Asp content and to a relatively high NO level. Consequently, to determine the exogenous effects of the two amino acids on testosterone synthesis, we carried out in vitro experiments using testis sections deriving from both the RP and NRP. When testis slices were incubated for 60 or 120 min with D-Asp, testosterone was enhanced, whereas in the presence of L-Arg, a precursor of NO, it was inhibited. CONCLUSION Our results provide new insights into the involvement of D-Asp and NO in testicular testosterone production in the adult captive wild-strain mallard drake. The localization of these two molecules in the Leydig cells in different periods of the reproductive cycle demonstrates that they play a potential role in regulating local testosterone production.
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Affiliation(s)
- Maria M Di Fiore
- Department of Life Sciences, Second University of Naples, via Vivaldi 43, 81100 Caserta, Italy.
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Oxidative alterations induced by d-aspartic acid in prepubertal rat testis in vitro: A mechanistic study. Theriogenology 2008; 70:97-104. [DOI: 10.1016/j.theriogenology.2008.02.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2007] [Revised: 01/25/2008] [Accepted: 02/24/2008] [Indexed: 12/19/2022]
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38
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D'Aniello A. d-Aspartic acid: An endogenous amino acid with an important neuroendocrine role. ACTA ACUST UNITED AC 2007; 53:215-34. [PMID: 17118457 DOI: 10.1016/j.brainresrev.2006.08.005] [Citation(s) in RCA: 197] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 07/14/2006] [Accepted: 08/04/2006] [Indexed: 12/01/2022]
Abstract
D-Aspartic acid (d-Asp), an endogenous amino acid present in vertebrates and invertebrates, plays an important role in the neuroendocrine system, as well as in the development of the nervous system. During the embryonic stage of birds and the early postnatal life of mammals, a transient high concentration of d-Asp takes place in the brain and in the retina. d-Asp also acts as a neurotransmitter/neuromodulator. Indeed, this amino acid has been detected in synaptosomes and in synaptic vesicles, where it is released after chemical (K(+) ion, ionomycin) or electric stimuli. Furthermore, d-Asp increases cAMP in neuronal cells and is transported from the synaptic clefts to presynaptic nerve cells through a specific transporter. In the endocrine system, instead, d-Asp is involved in the regulation of hormone synthesis and release. For example, in the rat hypothalamus, it enhances gonadotropin-releasing hormone (GnRH) release and induces oxytocin and vasopressin mRNA synthesis. In the pituitary gland, it stimulates the secretion of the following hormones: prolactin (PRL), luteinizing hormone (LH), and growth hormone (GH) In the testes, it is present in Leydig cells and is involved in testosterone and progesterone release. Thus, a hypothalamus-pituitary-gonads pathway, in which d-Asp is involved, has been formulated. In conclusion, the present work is a summary of previous and current research done on the role of d-Asp in the nervous and endocrine systems of invertebrates and vertebrates, including mammals.
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Affiliation(s)
- Antimo D'Aniello
- Laboratory of Neurobiology, Stazione Zoologica A Dohrn, Villa Comunale 1, 80121 Napoli, Italy.
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Lamanna C, Assisi L, Vittoria A, Botte V, Di Fiore MM. d-Aspartic acid and nitric oxide as regulators of androgen production in boar testis. Theriogenology 2007; 67:249-54. [PMID: 16996125 DOI: 10.1016/j.theriogenology.2006.07.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Revised: 06/23/2006] [Accepted: 07/24/2006] [Indexed: 11/19/2022]
Abstract
D-Aspartic acid (D-Asp) and nitric oxide (NO) are two biologically active molecules playing important functions as neurotransmitters and neuromodulators of nerve impulse and as regulators of hormone production by endocrine organs. We studied the occurrence of D-Asp and NO as well as their effects on testosterone synthesis in the testis of boar. This model was chosen for our investigations because it contains more Leydig cells than other mammals. Indirect immunofluorescence applied to cryostat sections was used to evaluate the co-localization of D-Asp and of the enzyme nitric oxide synthase (NOS) in the same Leydig cells. D-Asp and NOS often co-existed in the same Leydig cells and were found, separately, in many other testicular cytotypes. D-Asp level was dosed by an enzymatic method performed on boar testis extracts and was 40+/-3.6 nmol/g of fresh tissue. NO measurement was carried out using a biochemical method by NOS activity determination and expressed as quantity of nitrites produced: it was 155.25+/-21.9 nmol/mg of tissue. The effects of the two molecules on steroid hormone production were evaluated by incubating testis homogenates, respectively with or without D-Asp and/or the NO-donor L-arginine (L-Arg). After incubation, the testosterone presence was measured by immunoenzymatic assay (EIA). These in vitro experiments showed that the addition of D-Asp to incubated testicular homogenates significantly increased testosterone concentration, whereas the addition of L-Arg decreased the hormone production. Moreover, the inclusion of L-Arg to an incubation medium of testicular homogenates with added D-Asp, completely inhibited the stimulating effects of this enantiomer. Our results suggest an autocrine action of both D-Asp and NO on the steroidogenetic activity of the Leydig cell.
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Affiliation(s)
- Claudia Lamanna
- Department of Life Sciences, Second University of Naples, via Vivaldi 43, 81100 Caserta, Italy
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Hamase K, Takagi S, Morikawa A, Konno R, Niwa A, Zaitsu K. Presence and origin of large amounts of d-proline in the urine of mutant mice lacking d-amino acid oxidase activity. Anal Bioanal Chem 2006; 386:705-11. [PMID: 16924383 DOI: 10.1007/s00216-006-0594-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2006] [Revised: 05/29/2006] [Accepted: 06/02/2006] [Indexed: 10/24/2022]
Abstract
Using a column-switching HPLC system combining a micro-ODS column and a chiral column, the amounts of D-proline (D-Pro) have been determined in 18 tissues, plasma and urine of mice. To avoid the enzymatic degradation of D-amino acids in vivo, a mutant mouse strain lacking D-amino acid oxidase activity (ddY/DAO(-) mouse) was used. In the brain, relatively large amounts of D-Pro were observed in the anterior pituitary, posterior pituitary and pineal glands. In the peripheral tissues, the amounts of D-Pro were high in the pancreas and kidney. Above all, it is surprising that the ddY/DAO(-) mice excreted large amounts of D-Pro in their urine (433 nmol/mL, 20 times that of L-Pro). The origin of D-Pro has also been investigated. By comparing germ-free mice and gnotobiotic mice, intestinal bacteria were shown to have no effect on the urinary D-Pro amount. Concerning the dietary origin, a notable amount of D-Pro was still excreted in the urine after starvation for 4 days, suggesting that some of the D-Pro is produced in the mice. Age-dependent changes in the urinary D-Pro amount have also been investigated from the postnatal 1st month up to 12 months, and ddY/DAO(-) mice were found to excrete large amounts of D-Pro in the urine constantly throughout their lives.
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Affiliation(s)
- Kenji Hamase
- Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812 8582, Japan
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41
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Homma H. Biochemistry of D-aspartate in mammalian cells. Amino Acids 2006; 32:3-11. [PMID: 16755369 DOI: 10.1007/s00726-006-0354-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2006] [Accepted: 01/10/2006] [Indexed: 12/23/2022]
Abstract
Recent investigations have shown that D-aspartate (D-Asp) plays an important physiological role(s) in the mammalian body. Here, several recent studies of free D-Asp metabolism in mammals, focusing on cellular localization in tissues, intracellular localization, biosynthesis, efflux, uptake and degradation are reviewed. D-Asp in mammalian tissues is present in specific cells, indicating the existence of specific molecular components that regulate D-Asp levels and localization in tissues. In the rat pheochromocytoma cell line (PC12) and its subclones, D-Asp is synthesized intracellularly, most likely by Asp racemase(s). Endogenous D-Asp apparently has two different intracellular localization patterns: cytoplasmic and vesicular. In PC12 cells, D-Asp release can occur through three distinct pathways: 1) spontaneous, continuous release of cytoplasmic D-Asp, which is not associated with a specific stimulus; 2) release of cytoplasmic D-Asp via a volume-sensitive organic anion channel that connects the cytoplasm and extracellular space; 3) exocytotic discharge of vesicular D-Asp. Under certain conditions, D-Asp can be released via a mechanism that involves the L-Glu transporter. D-Asp is thus apparently in dynamic flux at the cellular level to carry out its physiological function(s) in mammals.
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Affiliation(s)
- H Homma
- Laboratory of Biomolecular Science, School of Pharmaceutical Sciences, Kitasato University, Tokyo, Japan.
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42
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Errico F, Pirro MT, Affuso A, Spinelli P, De Felice M, D'Aniello A, Di Lauro R. A physiological mechanism to regulate d-aspartic acid and NMDA levels in mammals revealed by d-aspartate oxidase deficient mice. Gene 2006; 374:50-7. [PMID: 16516413 DOI: 10.1016/j.gene.2006.01.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Accepted: 01/13/2006] [Indexed: 11/18/2022]
Abstract
Free D-aspartic acid and NMDA are present in the mammalian central nervous system and endocrine glands at significant concentrations, but their physiological role is still matter of debate. The only enzyme known to metabolize in vitro selectively these D-amino acids is D-aspartate oxidase (DDO). To clarify the role in vivo of the enzyme, we generated mice with targeted deletion of Ddo gene by homologous recombination. Mutated animals showed increased amounts of both D-aspartic acid and NMDA in all tissues examined demonstrating a physiological role of DDO in the regulation of their endogenous levels.
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Affiliation(s)
- Francesco Errico
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
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Lamanna C, Assisi L, Botte V, Di Fiore MM. Involvement of D-Asp in P450 aromatase activity and estrogen receptors in boar testis. Amino Acids 2006; 32:45-51. [PMID: 17469225 DOI: 10.1007/s00726-006-0351-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Mammalian testis contains D-aspartic acid (D-Asp), which enhances testosterone production. D-Asp, on other hand, also stimulates 17beta-estradiol synthesis in the ovary of some lower vertebrates. We studied boar testis in order to determine if D-Asp intervenes in 17beta-estradiol synthesis in the testis of those mammals which produce significant amounts of estrogens as well as testosterone. The boar testis contains D-Asp (40 +/- 3.6 nmol/g tissue) which, according to immunohistological techniques, is localized mainly in Leydig cells, and, to a lesser extent, in sustentacular (Sertoli), peritubular and some germ cells. The enzyme P450aromatase is present in Leydig cells and few germ cells. In vitro experiments showed that the addition of D-Asp to testicular tissue extracts induced a significant increase of aromatase activity, as evaluated by testosterone conversion into 17beta-estradiol. The enzyme's K(m) was not affected by D-Asp (about 25 nM in both control and D-Asp added tests). On the basis of these results we suggest that, as in the ovary, D-Asp is involved in the local control of aromatase activity of boar testis and, therefore, it intervenes in the 17beta-estradiol production. In the testis, the D-Asp targets are presumably the Leydig cells, which having also a nuclear estrogen receptor are, in turn, one of the putative targets of the 17beta-estradiol that they produce (autocrine effect).
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Affiliation(s)
- C Lamanna
- Department of Life Sciences, Second University of Naples, Caserta, Italy
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Spinelli P, Brown ER, Ferrandino G, Branno M, Montarolo PG, D'Aniello E, Rastogi RK, D'Aniello B, Baccari GC, Fisher G, D'Aniello A. D-aspartic acid in the nervous system of Aplysia limacina: possible role in neurotransmission. J Cell Physiol 2006; 206:672-81. [PMID: 16222705 DOI: 10.1002/jcp.20513] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In the marine mollusk Aplysia limacina, a substantial amount of endogenous D-aspartic acid (D-Asp) was found following its synthesis from L-aspartate by an aspartate racemase. Concentrations of D-Asp between 3.9 and 4.6 micromol/g tissue were found in the cerebral, abdominal, buccal, pleural, and pedal ganglia. In non nervous tissues, D-Asp occurred at a very low concentration compared to the nervous system. Immunohistochemical studies conducted on cultured Aplysia neurons using an anti-D-aspartate antibody demonstrated that D-Asp occurs in the soma, dendrites, and in synaptic varicosities. Synaptosomes and synaptic vesicles from cerebral ganglia were prepared and characterized by electron microscopy. HPLC analysis revealed high concentrations of D-Asp together with L-aspartate and L-glutamate in isolated synaptosomes In addition, D-Asp was released from synaptosomes by K+ depolarization or by ionomycin. D-Asp was one of the principal amino acids present in synaptic vesicles representing about the 25% of total amino acids present in these cellular organelles. Injection of D-Asp into live animals or addition to the incubation media of cultured neurons, caused an increase in cAMP content. Taken as a whole, these findings suggest a possible role of D-Asp in neurotransmission in the nervous system of Aplysia limacina.
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Affiliation(s)
- Patrizia Spinelli
- Laboratory of Neurobiology, Stazione Zoologica A. Dohrn, Villa Comunale, Napoli, Italy
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45
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Boni R, Santillo R, Macchia G, Spinelli P, Ferrandino G, D'Aniello A. d-Aspartate and reproductive activity in sheep. Theriogenology 2006; 65:1265-78. [PMID: 16203031 DOI: 10.1016/j.theriogenology.2005.07.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2005] [Revised: 07/06/2005] [Accepted: 07/31/2005] [Indexed: 10/25/2022]
Abstract
D-aspartic acid (D-Asp) has been isolated from neuroendocrine tissues of many invertebrates and vertebrates. Recently, it has been demonstrated that this D-amino acid may be converted to N-methyl-D-aspartic acid (NMDA), a neuromodulator associated with sexual activity. In this study, we determined D-Asp and NMDA concentrations in endocrine glands and other tissues in ewes after D-Asp administration and in controls. We also evaluated the effects of d-Asp administration on the reproductive activity of ewes by determining either progesterone concentrations or LH pulses in the presence or absence of estradiol benzoate. The pineal gland showed the highest natural content of D-Asp (1.47+/-0.22 micromol/g tissue), whereas the pituitary gland had the highest capability to store d-Asp, with a peak value (9.7+/-0.81 micromol/g tissue) 6 h after its administration. NMDA increased sharply 12 h following D-Asp administration, reaching values three times higher than the baseline in both the pituitary and brain. D-Asp was quickly adsorbed after subcutaneous administration, with a peak in plasma levels 2 h after administration and a return to baseline values after 6 h. D-Asp administration achieved a significant (P < 0.001) increase in LH values with respect to estradiol or estradiol + D-Asp treatments. d-Asp treatment once or twice a week did not successfully drive acyclic ewes into reproductive activity. In conclusion, the results obtained in this study demonstrated that D-Asp is endogenously present in sheep tissues and electively stored in endocrine glands and brain after its administration. NMDA and LH increase following D-Asp administration suggesting a role of this D-amino acid in the reproductive activity of sheep.
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Affiliation(s)
- R Boni
- Department of Animal Science, University of Basilicata, Campus Macchia Romana, 85100 Potenza, Italy.
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Lamanna C, Assisi L, Botte V, Di Fiore MM. Endogenous testicular D-aspartic acid regulates gonadal aromatase activity in boar. J Endocrinol Invest 2006; 29:141-6. [PMID: 16610240 DOI: 10.1007/bf03344087] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
D-aspartic acid (D-Asp), aromatase enzyme activity and the putative D-Asp involvement on aromatase induction have been studied in the testis of mature boars. The peroxidase-antiperoxidase and the indirect immunofluorescence methods, applied to cryostat and paraffin sections, were used to evaluate D-Asp and aromatase distributions. D-Asp level was dosed by an enzymatic method performed on boar testis extracts. Biochemical aromatase activity was determined by in vitro experiments carried out on testis extracts. D-Asp immunoreactivity was found in Leydig cells, and, to a lesser extent, in germ cells. Analogously, aromatase immunoreactivity was present in Leydig cells, but absent from seminiferous tubule elements. In vitro experiments showed that the addition of D-Asp to testicular tissue acetone powder induced a significant increase of aromatase activity, as assessed by testosterone conversion to 17beta-estradiol. Enzyme Km was not affected by D-Asp (about 25 nM in control and D-Asp added tests). These findings suggest that D-Asp could be involved in the local regulation of aromatase in boar Leydig cells and intervenes in this organ's production of estrogens.
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Affiliation(s)
- C Lamanna
- Department of Zoology, University of Naples 'Federico II', Naples, Italy
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D'Aniello G, Ronsini S, Guida F, Spinelli P, D'Aniello A. Occurrence of D-aspartic acid in human seminal plasma and spermatozoa: possible role in reproduction. Fertil Steril 2006; 84:1444-9. [PMID: 16275242 DOI: 10.1016/j.fertnstert.2005.05.019] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Revised: 05/01/2005] [Accepted: 05/01/2005] [Indexed: 10/25/2022]
Abstract
OBJECTIVE To determine D-aspartic acid (D-Asp) in human seminal plasma and spermatozoa in fertile and infertile donors. DESIGN Prospective observation study. SETTING Department of Pathophysiology for Human Reproduction, Hospital "S. Luca," Salerno, Italy, and Department of Neurobiology and Comparative Physiology, Zoological Station "A. Dohrn," Naples, Italy. PATIENT(S) Ten normospermic, 10 oligoasthenoteratospermic, and 10 azoospermic (nonobstructive) men. INTERVENTION(S) D-aspartic acid was determined by a specific enzymatic high-performance liquid chromatography method on purified seminal plasma and on isolated spermatozoa and by an immunohistochemical method using light and electronic microscopic techniques. MAIN OUTCOME MEASURE(S) Concentration of D-Asp in seminal plasma and in isolated spermatozoa; subcellular localization of D-Asp in the acrosome and nucleus. RESULT(S) The concentration of D-Asp in seminal plasma and in spermatozoa was significantly reduced in oligoasthenoteratospermic donors. In the seminal fluid of normospermic donors, D-Asp occurs at a concentration of 80 +/- 12 nmol/mL semen (10.4 +/- 1.5 microg/mL), whereas 26 +/- 6 nmol/mL semen were found in oligoasthenoteratospermic donors, and 12 +/- 1.5 nmol/mL semen were found in azoospermic donors. In spermatozoa from normospermic donors, D-Asp occurred at a concentration of 130 +/-15 fmol per spermatozoa (17.0 +/- 1.96 ng per spermatozoa), vs. 60.5 +/- 5.0 fmol per spermatozoa from oligoasthenoteratospermic subjects. Other D-amino acids analyzed were not present in seminal plasma or in spermatozoa in a significant concentration compared with D-Asp. CONCLUSION(S) D-aspartic acid occurs in human seminal plasma and spermatozoa and is implicated in male fertility.
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Affiliation(s)
- Gemma D'Aniello
- Department of Obstetrics and Gynecology and Physiopathology of Human Reproduction, Hospital S. Luca, Salerno, Italy.
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Abstract
D-Aspartate (D-Asp) is an especially intriguing molecule found within neurons of the central nervous system of animals ranging from mollusks to vertebrates. It has a large variety of roles ascribed to it, including an involvement in cell-to-cell signaling. To determine the D-Asp content in cells and in subcellular domains, a laboratory-assembled capillary electrophoresis system with laser-induced fluorescence (LIF) detection has been used. The system allows chiral separations with sufficient sensitivity and selectivity to measure the D-Asp content in specific subregions of a single neuron, including neuronal processes. The method uses microvial sampling, analyte derivatization with naphthalene-2,3-dicarboxaldehyde, cyclodextrin-mediated micellar electrokinetic capillary chromatography, and sheath flow cell-based LIF detection. Manipulating neuronal processes is difficult as they often disintegrate during the transfer to the sampling vial. We describe a glycerol treatment that stabilizes cell morphology during sample preparation, thereby alleviating the deleterious effects of the high-salt extracellular matrix on the electrophoretic separation. D-Asp percentages in processes from identified neurons from Aplysia californica differ significantly depending on the cell studied. Subcellular analysis reveals more compounds in the cell body than in the processes.
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Affiliation(s)
- Hai Miao
- Department of Chemistry, University of Illinois at Urbana--Champaign, 61801, USA
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D'Aniello S, Spinelli P, Ferrandino G, Peterson K, Tsesarskia M, Fisher G, D'Aniello A. Cephalopod vision involves dicarboxylic amino acids: D-aspartate, L-aspartate and L-glutamate. Biochem J 2005; 386:331-40. [PMID: 15491279 PMCID: PMC1134798 DOI: 10.1042/bj20041070] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2004] [Revised: 09/08/2004] [Accepted: 10/18/2004] [Indexed: 11/17/2022]
Abstract
In the present study, we report the finding of high concentrations of D-Asp (D-aspartate) in the retina of the cephalopods Sepia officinalis, Loligo vulgaris and Octopus vulgaris. D-Asp increases in concentration in the retina and optic lobes as the animal develops. In neonatal S. officinalis, the concentration of D-Asp in the retina is 1.8+/-0.2 micromol/g of tissue, and in the optic lobes it is 5.5+/-0.4 micromol/g of tissue. In adult animals, D-Asp is found at a concentration of 3.5+/-0.4 micromol/g in retina and 16.2+/-1.5 micromol/g in optic lobes (1.9-fold increased in the retina, and 2.9-fold increased in the optic lobes). In the retina and optic lobes of S. officinalis, the concentration of D-Asp, L-Asp (L-aspartate) and L-Glu (L-glutamate) is significantly influenced by the light/dark environment. In adult animals left in the dark, these three amino acids fall significantly in concentration in both retina (approx. 25% less) and optic lobes (approx. 20% less) compared with the control animals (animals left in a diurnal/nocturnal physiological cycle). The reduction in concentration is in all cases statistically significant (P=0.01-0.05). Experiments conducted in S. officinalis by using D-[2,3-3H]Asp have shown that D-Asp is synthesized in the optic lobes and is then transported actively into the retina. D-aspartate racemase, an enzyme which converts L-Asp into D-Asp, is also present in these tissues, and it is significantly decreased in concentration in animals left for 5 days in the dark compared with control animals. Our hypothesis is that the dicarboxylic amino acids, D-Asp, L-Asp and L-Glu, play important roles in vision.
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Key Words
- d-aspartate racemase
- cephalopod
- dicarboxylic amino acid
- mollusc
- vision
- d-aao, d-amino acid oxidase
- d-aspo, d-aspartate oxidase
- gh, growth hormone
- lh, luteinizing hormone
- nac, n-acetylcysteine
- nmda, n-methyl-d-aspartate
- ods, octadecylsilyl
- opa, o-phthalaldehyde
- pod, horseradish peroxidase
- tca, trichloroacetic acid
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Affiliation(s)
- Salvatore D'Aniello
- *Laboratory of Biochemistry and Molecular Biology, Zoological Station of Naples, Villa Comunale, 80121 Naples, Italy
| | - Patrizia Spinelli
- †Laboratory of Neurobiology and Comparative Neurophysiology, Zoological Station of Naples, Villa Comunale, 80121 Naples, Italy
| | - Gabriele Ferrandino
- †Laboratory of Neurobiology and Comparative Neurophysiology, Zoological Station of Naples, Villa Comunale, 80121 Naples, Italy
| | - Kevin Peterson
- ‡Department of Chemistry, Barry University, Miami Shores, FL 33161, U.S.A
| | - Mara Tsesarskia
- ‡Department of Chemistry, Barry University, Miami Shores, FL 33161, U.S.A
| | - George Fisher
- ‡Department of Chemistry, Barry University, Miami Shores, FL 33161, U.S.A
| | - Antimo D'Aniello
- †Laboratory of Neurobiology and Comparative Neurophysiology, Zoological Station of Naples, Villa Comunale, 80121 Naples, Italy
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Abstract
D-Aspartate (D-Asp) is an endogenous amino acid present in nervous and endocrine tissues in mammals. A high concentration of D-Asp is observed in embryos, which disappears in nervous tissues after delivery, but increases temporarily in endocrine glands, particularly in the pituitary, pineal and adrenal glands at the specific stages. In the pineal gland, D-Asp that is apparently derived from other tissues suppresses melatonin secretion from parenchymal cells. Additionally, D-Asp levels increase in the testis just before birth and during maturation. The amino acid is presumed to be synthesized by the pituitary gland and testis. In the testis, D-Asp produced inside the seminiferous tubules acts on Leydig cells following release to enhance testosterone synthesis by activating the expression of Steroidogenic Acute Regulatory protein. Mammalian cells appear to contain all the molecular components required to regulate D-Asp homeostasis, as they can synthesize, release, take up, and degrade the amino acid. These findings collectively indicate that D-Asp is a novel type of messenger in the mammalian body.
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Affiliation(s)
- Takemitsu Furuchi
- Laboratory of Biomolecular Science, School of Pharmaceutical Sciences, Kitasato University, Tokyo, Japan
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