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Diviccaro S, Cioffi L, Piazza R, Caruso D, Melcangi RC, Giatti S. Neuroactive Steroid-Gut Microbiota Interaction in T2DM Diabetic Encephalopathy. Biomolecules 2023; 13:1325. [PMID: 37759725 PMCID: PMC10527303 DOI: 10.3390/biom13091325] [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: 07/12/2023] [Revised: 08/11/2023] [Accepted: 08/21/2023] [Indexed: 09/29/2023] Open
Abstract
The pathological consequences of type 2 diabetes mellitus (T2DM) also involve the central nervous system; indeed, T2DM patients suffer from learning and memory disabilities with a higher risk of developing dementia. Although several factors have been proposed as possible contributors, how neuroactive steroids and the gut microbiome impact brain pathophysiology in T2DM remain unexplored. On this basis, in male Zucker diabetic fatty (ZDF) rats, we studied whether T2DM alters memory abilities using the novel object recognition test, neuroactive steroid levels by liquid chromatography-tandem mass spectrometry, hippocampal parameters using molecular assessments, and gut microbiome composition using 16S next-generation sequencing. Results obtained reveal that T2DM worsens memory abilities and that these are correlated with increased levels of corticosterone in plasma and with a decrease in allopregnanolone in the hippocampus, where neuroinflammation, oxidative stress, and mitochondrial dysfunction were reported. Interestingly, our analysis highlighted a small group of taxa strictly related to both memory impairment and neuroactive steroid levels. Overall, the data underline an interesting role for allopregnanolone and microbiota that may represent candidates for the development of therapeutic strategies.
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Affiliation(s)
- Silvia Diviccaro
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, 20133 Milan, Italy; (S.D.); (L.C.); (D.C.); (R.C.M.)
| | - Lucia Cioffi
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, 20133 Milan, Italy; (S.D.); (L.C.); (D.C.); (R.C.M.)
| | - Rocco Piazza
- Dipartimento di Medicina e Chirurgia, Università di Milano—Bicocca, 20126 Milan, Italy;
| | - Donatella Caruso
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, 20133 Milan, Italy; (S.D.); (L.C.); (D.C.); (R.C.M.)
| | - Roberto Cosimo Melcangi
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, 20133 Milan, Italy; (S.D.); (L.C.); (D.C.); (R.C.M.)
| | - Silvia Giatti
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, 20133 Milan, Italy; (S.D.); (L.C.); (D.C.); (R.C.M.)
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Takeshita RS, Edler MK, Meindl RS, Sherwood CC, Hopkins WD, Raghanti MA. Age, adrenal steroids, and cognitive functioning in captive chimpanzees ( Pan troglodytes). PeerJ 2022; 10:e14323. [PMID: 36389417 PMCID: PMC9653054 DOI: 10.7717/peerj.14323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 10/10/2022] [Indexed: 11/11/2022] Open
Abstract
Background Dehydroepiandrosterone-sulfate is the most abundant circulating androgen in humans and other catarrhines. It is involved in several biological functions, such as testosterone production, glucocorticoid antagonist actions, neurogenesis and neuroplasticty. Although the role of dehydroepiandrosterone-sulfate (DHEAS) in cognition remains elusive, the DHEAS/cortisol ratio has been positively associated with a slower cognitive age-decline and improved mood in humans. Whether this relationship is found in nonhuman primates remains unknown. Methods We measured DHEAS and cortisol levels in serum of 107 adult chimpanzees to investigate the relationship between DHEAS levels and age. A subset of 21 chimpanzees was used to test the potential associations between DHEAS, cortisol, and DHEAS/cortisol ratio in cognitive function, taking into account age, sex, and their interactions. We tested for cognitive function using the primate cognitive test battery (PCTB) and principal component analyses to categorize cognition into three components: spatial relationship tasks, tool use and social communication tasks, and auditory-visual sensory perception tasks. Results DHEAS levels, but not the DHEAS/cortisol ratio, declined with age in chimpanzees. Our analyses for spatial relationships tasks revealed a significant, positive correlation with the DHEAS/cortisol ratio. Tool use and social communication had a negative relationship with age. Our data show that the DHEAS/cortisol ratio, but not DHEAS individually, is a promising predictor of spatial cognition in chimpanzees.
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Affiliation(s)
- Rafaela S.C. Takeshita
- Department of Anthropology, Kent State University, Kent, OH, USA,School of Biomedical Sciences, Kent State University, Kent, OH, USA,Brain Health Research Institute, Kent State University, Kent, OH, USA
| | - Melissa K. Edler
- Department of Anthropology, Kent State University, Kent, OH, USA,School of Biomedical Sciences, Kent State University, Kent, OH, USA,Brain Health Research Institute, Kent State University, Kent, OH, USA
| | - Richard S. Meindl
- Department of Anthropology, Kent State University, Kent, OH, USA,School of Biomedical Sciences, Kent State University, Kent, OH, USA
| | - Chet C. Sherwood
- Department of Anthropology, The George Washington University, Washington, DC, USA
| | - William D. Hopkins
- Department of Comparative Medicine, The University of Texas MD Anderson Cancer Center, Bastrop, TX, USA
| | - Mary Ann Raghanti
- Department of Anthropology, Kent State University, Kent, OH, USA,School of Biomedical Sciences, Kent State University, Kent, OH, USA,Brain Health Research Institute, Kent State University, Kent, OH, USA
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Penhale SH, Picci G, Ott LR, Taylor BK, Frenzel MR, Eastman JA, Wang YP, Calhoun VD, Stephen JM, Wilson TW. Impacts of adrenarcheal DHEA levels on spontaneous cortical activity during development. Dev Cogn Neurosci 2022; 57:101153. [PMID: 36174268 PMCID: PMC9519481 DOI: 10.1016/j.dcn.2022.101153] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 08/10/2022] [Accepted: 09/15/2022] [Indexed: 11/25/2022] Open
Abstract
Dehydroepiandrosterone (DHEA) production is closely associated with the first pubertal hormonal event, adrenarche. Few studies have documented the relationships between DHEA and functional brain development, with even fewer examining the associations between DHEA and spontaneous cortical activity during the resting-state. Thus, whether DHEA levels are associated with the known developmental shifts in the brain's idling cortical rhythms remains poorly understood. Herein, we examined spontaneous cortical activity in 71 typically-developing youth (9-16 years; 32 male) using magnetoencephalography (MEG). MEG data were source imaged and the power within five canonical frequency bands (delta, theta, alpha, beta, gamma) was computed to identify spatially- and spectrally-specific effects of salivary DHEA and DHEA-by-sex interactions using vertex-wise ANCOVAs. Our results indicated robust increases in power with increasing DHEA within parieto-occipital cortices in all frequency bands except alpha, which decreased with increasing DHEA. In the delta band, DHEA and sex interacted within frontal and temporal cortices such that with increasing DHEA, males exhibited increasing power while females showed decreasing power. These data suggest that spontaneous cortical activity changes with endogenous DHEA levels during the transition from childhood to adolescence, particularly in sensory and attentional processing regions. Sexually-divergent trajectories were only observed in later-developing frontal cortical areas.
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Affiliation(s)
- Samantha H Penhale
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
| | - Giorgia Picci
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
| | - Lauren R Ott
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
| | - Brittany K Taylor
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA; Department of Pharmacology & Neuroscience, Creighton University, Omaha, NE, USA
| | - Michaela R Frenzel
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
| | - Jacob A Eastman
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
| | - Yu-Ping Wang
- Department of Biomedical Engineering, Tulane University, New Orleans, LA, USA
| | - Vince D Calhoun
- Tri-institutional Center for Translational Research in Neuroimaging and Data Science (TReNDS), Georgia State University, Georgia Institute of Technology, Emory University, Atlanta, GA, USA
| | | | - Tony W Wilson
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA; Department of Pharmacology & Neuroscience, Creighton University, Omaha, NE, USA.
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4
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Li LJ, Li CH, Chang PMH, Lai TC, Yong CY, Feng SW, Hsiao M, Chang WM, Huang CYF. Dehydroepiandrosterone (DHEA) Sensitizes Irinotecan to Suppress Head and Neck Cancer Stem-Like Cells by Downregulation of WNT Signaling. Front Oncol 2022; 12:775541. [PMID: 35912234 PMCID: PMC9328800 DOI: 10.3389/fonc.2022.775541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 06/13/2022] [Indexed: 12/24/2022] Open
Abstract
Purpose Current treatment options for head and neck squamous cell carcinoma (HNSCC) are limited, especially for cases with cancer stem cell-induced chemoresistance and recurrence. The WNT signaling pathway contributes to maintenance of stemness via translocation of β-catenin into the nucleus, and represents a promising druggable target in HNSCC. Dehydroepiandrosterone (DHEA), a steroid hormone, has potential as an anticancer drug. However, the potential anticancer mechanisms of DHEA including inhibition of stemness, and its therapeutic applications in HNSCC remain unclear. Methods Firstly, SRB assay and sphere formation assay were used to examine cellular viability and cancer stem cell-like phenotype, respectively. The expressions of stemness related factors were measured by RT-qPCR and western blotting. The luciferase reporter assay was applied to evaluate transcriptional potential of stemness related pathways. The alternations of WNT signaling pathway were measured by nuclear translocation of β-catenin, RT-qPCR and western blotting. Furthermore, to investigate the effect of drugs in vivo, both HNSCC orthotopic and subcutaneous xenograft mouse models were applied. Results We found that DHEA reduced HNSCC cell viability, suppressed sphere formation, and inhibited the expression of cancer-stemness markers, such as BMI-1 and Nestin. Moreover, DHEA repressed the transcriptional activity of stemness-related pathways. In the WNT pathway, DHEA reduced the nuclear translocation of the active form of β-catenin and reduced the protein expression of the downstream targets, CCND1 and CD44. Furthermore, when combined with the chemotherapeutic drug, irinotecan (IRN), DHEA enhanced the sensitivity of HNSCC cells to IRN as revealed by reduced cell viability, sphere formation, expression of stemness markers, and activation of the WNT pathway. Additionally, this combination reduced in vivo tumor growth in both orthotopic and subcutaneous xenograft mouse models. Conclusion These findings indicate that DHEA has anti-stemness potential in HNSCC and serves as a promising anticancer agent. The combination of DHEA and IRN may provide a potential therapeutic strategy for patients with advanced HNSCC.
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Affiliation(s)
- Li-Jie Li
- Ph.D. Program in School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chien-Hsiu Li
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Peter Mu-Hsin Chang
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Department of Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
- Faculty of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Tsung-Ching Lai
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
- Division of Pulmonary Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Chen-Yin Yong
- Division of Oral and Maxillofacial Surgery, Department of Dentistry Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Sheng-Wei Feng
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Prosthodontics, Department of Dentistry, Taipei Medical University Hospital, Taipei, Taiwan
| | - Michael Hsiao
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
- Department of Biochemistry, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Wei-Min Chang
- School of Oral Hygiene, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
- *Correspondence: Chi-Ying F. Huang, ; Wei-Min Chang,
| | - Chi-Ying F. Huang
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Department of Biochemistry, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- *Correspondence: Chi-Ying F. Huang, ; Wei-Min Chang,
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Fung MH, Rahman RL, Taylor BK, Frenzel MR, Eastman JA, Wang Y, Calhoun VD, Stephen JM, Wilson TW. The impact of pubertal DHEA on the development of visuospatial oscillatory dynamics. Hum Brain Mapp 2022; 43:5154-5166. [PMID: 35778797 PMCID: PMC9812248 DOI: 10.1002/hbm.25991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 05/26/2022] [Accepted: 05/29/2022] [Indexed: 01/15/2023] Open
Abstract
The adolescent brain undergoes tremendous structural and functional changes throughout puberty. Previous research has demonstrated that pubertal hormones can modulate sexually dimorphic changes in cortical development, as well as age-related maturation of the neural activity underlying cognitive processes. However, the precise impact of pubertal hormones on these functional changes in the developing human brain remains poorly understood. In the current study, we quantified the neural oscillatory activity serving visuospatial processing using magnetoencephalography, and utilized measures of dehydroepiandrosterone (DHEA) as an index of development during the transition from childhood to adolescence (i.e., puberty). Within a sample of typically developing youth (ages 9-15), a novel association between pubertal DHEA and theta oscillatory activity indicated that less mature children exhibited stronger neural responses in higher-order prefrontal cortices during the visuospatial task. Theta coherence between bilateral prefrontal regions also increased with increasing DHEA, such that network-level theta activity became more distributed with more maturity. Additionally, significant DHEA-by-sex interactions in the gamma range were centered on cortical regions relevant for attention processing. These findings suggest that pubertal DHEA may modulate the development of neural oscillatory activity serving visuospatial processing and attention functions during the pubertal period.
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Affiliation(s)
- Madison H. Fung
- Institute for Human NeuroscienceBoys Town National Research HospitalOmahaNebraskaUSA,Institute of Child DevelopmentUniversity of Minnesota‐Twin CitiesMinneapolisMinnesotaUSA
| | - Raeef L. Rahman
- Institute for Human NeuroscienceBoys Town National Research HospitalOmahaNebraskaUSA
| | - Brittany K. Taylor
- Institute for Human NeuroscienceBoys Town National Research HospitalOmahaNebraskaUSA
| | - Michaela R. Frenzel
- Institute for Human NeuroscienceBoys Town National Research HospitalOmahaNebraskaUSA
| | - Jacob A. Eastman
- Institute for Human NeuroscienceBoys Town National Research HospitalOmahaNebraskaUSA
| | - Yu‐Ping Wang
- Department of Biomedical EngineeringTulane UniversityNew OrleansLouisianaUSA
| | - Vince D. Calhoun
- Tri‐institutional Center for Translational Research in Neuroimaging and Data Science (TReNDS), Georgia State University, Georgia Institute of Technology, Emory UniversityAtlantaGeorgiaUSA
| | | | - Tony W. Wilson
- Institute for Human NeuroscienceBoys Town National Research HospitalOmahaNebraskaUSA
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Souza-Teodoro LH, Andrade LHS, Carvalho LA. Could be dehydroepiandrosterone (DHEA) a novel target for depression? JOURNAL OF AFFECTIVE DISORDERS REPORTS 2022. [DOI: 10.1016/j.jadr.2022.100340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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7
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The Utilization of Dehydroepiandrosterone as a Sexual Hormone Precursor in Premenopausal and Postmenopausal Women: An Overview. Pharmaceuticals (Basel) 2021; 15:ph15010046. [PMID: 35056103 PMCID: PMC8781653 DOI: 10.3390/ph15010046] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/16/2021] [Accepted: 12/27/2021] [Indexed: 12/03/2022] Open
Abstract
Dehydroepiandrosterone (DHEA), and its metabolite, dehydroepiandrosterone sulfate ester (DHEAS), are the most abundant circulating steroid hormones, and are synthesized in the zona reticularis of the adrenal cortex, in the gonads, and in the brain. The precise physiological role of DHEA and DHEAS is not yet fully understood, but these steroid hormones can act as androgens, estrogens, and neurosteroids, and perform many roles in the human body. Since both levels decline with age, use of DHEA supplements have gained more attention due to being advertised as an antidote to aging in postmenopausal women, who may have concerns on age-related diseases and overall well-being. However, current research has not reached an overall consensus on the effects of DHEA on postmenopausal women. This overview is a summary of the current literature, addressing the metabolic pathway for DHEA synthesis and utilization, as well as the effects of DHEA on premenopausal and postmenopausal women with disease states and other factors. As for the therapeutic effects on menopausal syndrome and other age-related diseases, several studies have found that DHEA supplementations can alleviate vasomotor symptoms, preserve the integrity of the immune system, reduce bone loss, and increase muscle mass. Intravaginal DHEA has shown significant beneficial effects in menopausal women with severe vulvovaginal symptoms. On the other hand, DHEA supplements have not shown definitive effects in cardiovascular disease, adrenal insufficiency, insulin sensitivity, and cognition. Due to inadequate sample sizes and treatment durations of current studies, it is difficult to assess the safety and efficacy of DHEA and draw reliable conclusions for the physiological role, the optimal dosage, and the effects on premenopausal and postmenopausal women; therefore, the study of DHEA warrants future investigation. Further research into the roles of these steroid hormones may bring us closer to a therapeutic option in the future.
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Brauer VS, Zambuzi FA, Espíndola MS, Cavalcanti Neto MP, Prado MKB, Cardoso PM, Soares LS, Galvao-Lima LJ, Leopoldino AM, Cardoso CRDB, Frantz FG. The influence of dehydroepiandrosterone on effector functions of neutrophils. BRAZ J PHARM SCI 2021. [DOI: 10.1590/s2175-97902020000419139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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9
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Pan X, Wu X, Kaminga AC, Wen SW, Liu A. Dehydroepiandrosterone and Dehydroepiandrosterone Sulfate in Alzheimer's Disease: A Systematic Review and Meta-Analysis. Front Aging Neurosci 2019; 11:61. [PMID: 30983988 PMCID: PMC6449476 DOI: 10.3389/fnagi.2019.00061] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 03/05/2019] [Indexed: 12/27/2022] Open
Abstract
Background and Purpose: Previous studies found inconsistent results for the relationship between Alzheimer's disease and the levels of dehydroepiandrosterone and dehydroepiandrosterone sulfate. This study performed a systematic review and meta-analysis to evaluate previous studies' results on this relationship. Method: Studies related to this outcome were obtained using a systematic search from the electronic databases of PubMed, Embase, Web of Science, and Psyc-ARTICLES in March 2018. The random-effects model was used to measure the strength of the association between Alzheimer's disease and the levels of dehydroepiandrosterone and dehydroepiandrosterone sulfate, using the standardized mean difference. Results: Thirty-one eligible studies were included in the final analysis. There was no statistically significant association between the level of dehydroepiandrosterone and Alzheimer's disease (standardized mean difference: 0.51, 95% confidence interval: -0.44 to 1.45, Z = 1.06, p = 0.29). On the other hand, lower level dehydroepiandrosterone sulfate was observed in patients with Alzheimer's disease than in controls (standardized mean difference: -0.69, 95% confidence interval: -1.17 to -0.22, Z = -2.84, p < 0.01). Conclusion: Decreased dehydroepiandrosterone sulfate concentrations may be an important indicator for Alzheimer's disease, although whether dehydroepiandrosterone sulfate could be used as a diagnostic tool requires further research.
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Affiliation(s)
- Xiongfeng Pan
- Department of Epidemiology and Health Statistics, Xiangya School of Public Health, Central South University, Changsha, China
| | - Xinyin Wu
- Department of Epidemiology and Health Statistics, Xiangya School of Public Health, Central South University, Changsha, China
| | - Atipatsa C Kaminga
- Department of Epidemiology and Health Statistics, Xiangya School of Public Health, Central South University, Changsha, China.,Department of Mathematics and Statistics, Mzuzu University, Mzuzu, Malawi
| | - Shi Wu Wen
- Department of Obstetrics and Gynaecology, University of Ottawa, Ottawa, ON, Canada.,Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Aizhong Liu
- Department of Epidemiology and Health Statistics, Xiangya School of Public Health, Central South University, Changsha, China
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Vegliante R, Ciriolo MR. Autophagy and Autophagic Cell Death: Uncovering New Mechanisms Whereby Dehydroepiandrosterone Promotes Beneficial Effects on Human Health. VITAMINS AND HORMONES 2018; 108:273-307. [PMID: 30029730 DOI: 10.1016/bs.vh.2018.01.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Dehydroepiandrosterone (DHEA) is the most abundant steroid hormone in human serum and a precursor of sexual hormones. Its levels, which are maximum between the age of 20 and 30, dramatically decline with aging thus raising the question that many pathological conditions typical of the elderly might be associated with the decrement of circulating DHEA. Moreover, since its very early discovery, DHEA and its metabolites have been shown to be active in many pathophysiological contexts, including cardiovascular disease, brain disorders, and cancer. Indeed, treatment with DHEA has beneficial effects for the cure of these and many other pathologies in vitro, in vivo, and in patient studies. However, the molecular mechanisms underlying DHEA effects have been only partially elucidated. Autophagy is a self-digestive process, by which cell homeostasis is maintained, damaged organelles removed, and cell survival assured upon stress stimuli. However, high rate of autophagy is detrimental and leads to a form of programmed cell death known as autophagic cell death (ACD). In this chapter, we describe the process of autophagy and the morphological and biochemical features of ACD. Moreover, we analyze the beneficial effects of DHEA in several pathologies and the molecular mechanisms with particular emphasis on its regulation of cell death processes. Finally, we review data indicating DHEA and structurally related steroid hormones as modulators of both autophagy and ACD, a research field that opens new avenues in the therapeutic use of these compounds.
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Affiliation(s)
- Rolando Vegliante
- MN3T, The Microenvironmental Niche in Tumorigenesis and Targeted Therapy, Hopital Civil-Institut d'Hématologie et Immunologie, Strasbourg, France
| | - Maria R Ciriolo
- University of Rome 'Tor Vergata', Rome, Italy; IRCCS San Raffaele 'La Pisana', Rome, Italy.
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11
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Chen CY, Wu CC, Huang YC, Hung CF, Wang LJ. Gender differences in the relationships among neurosteroid serum levels, cognitive function, and quality of life. Neuropsychiatr Dis Treat 2018; 14:2389-2399. [PMID: 30275693 PMCID: PMC6157536 DOI: 10.2147/ndt.s176047] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Dehydroepiandrosterone (DHEA), its sulfate ester (DHEA-S), and pregnenolone are neurosteroids that can be synthesized in the brain. Previous studies have hypothesized that these neurosteroids have antiaging, mood-enhancing, and cognitive-preserving effects; however, these effects may be gender-specific. Therefore, the purpose of this study was to investigate the gender differences in the relationships among neurosteroids (DHEA, DHEA-S, and pregnenolone), cognitive function, and quality of life in healthy individuals. METHOD In this cross-sectional study, we enrolled 47 men (mean age: 32.8 years) and 75 women (mean age: 35.4 years) who had no major physical or psychiatric illnesses and measured their serum DHEA, DHEA-S, and pregnenolone. Furthermore, we evaluated the subjects' cognitive function and quality of life using the Brief Assessment of Cognition in Schizophrenia and the World Health Organization Quality of Life Scale, respectively. RESULTS The serum levels of DHEA and DHEA-S demonstrated significant gender differences, even after controlling for age effect. In the male subjects, the DHEA serum levels were positively correlated with three domains of the World Health Organization Quality of Life Scale, including physical health, social relations, and environmental dimensions. Meanwhile, the DHEA-S levels positively correlated with the performance of working memory, and pregnenolone levels had a positive correlation with working memory, verbal fluency, and Brief Assessment of Cognition in Schizophrenia composite score. However, in the female subjects, we observed a correlation only between the serum levels of DHEA-S and working memory. CONCLUSION The findings of our study indicate that neurosteroids play a vital role in cognitive function and quality of life among men but less so among women. Nevertheless, the underlying mechanisms of the gender-specific effect of neurosteroids require further investigation.
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Affiliation(s)
- Chien-Yu Chen
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chih-Ching Wu
- Molecular Medicine Research Center, Chang Gung University, Tao-Yuan, Taiwan.,Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Tao-Yuan, Taiwan
| | - Yu-Chi Huang
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chi-Fa Hung
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Liang-Jen Wang
- Department of Child and Adolescent Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan,
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12
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Colín-Val Z, González-Puertos VY, Mendoza-Milla C, Gómez EO, Huesca-Gómez C, López-Marure R. DHEA increases epithelial markers and decreases mesenchymal proteins in breast cancer cells and reduces xenograft growth. Toxicol Appl Pharmacol 2017; 333:26-34. [PMID: 28803991 DOI: 10.1016/j.taap.2017.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 08/02/2017] [Accepted: 08/09/2017] [Indexed: 01/05/2023]
Abstract
Breast cancer is one of the most common neoplasias and the leading cause of cancer death in women worldwide. Its high mortality rate is linked to a great metastatic capacity associated with the epithelial-mesenchymal transition (EMT). During this process, a decrease in epithelial proteins expression and an increase of mesenchymal proteins are observed. On the other hand, it has been shown that dehydroepiandrosterone (DHEA), the most abundant steroid in human plasma, inhibits migration of breast cancer cells; however, the underlying mechanisms have not been elucidated. In this study, the in vitro effect of DHEA on the expression pattern of some EMT-related proteins, such as E-cadherin (epithelial), N-cadherin, vimentin and Snail (mesenchymal) was measured by Western blot and immunofluorescence in MDA-MB-231 breast cancer cells with invasive, metastatic and mesenchymal phenotype. Also, the in vivo effect of DHEA on xenograft tumor growth in nude mice (nu-/nu-) and on expression of the same epithelial and mesenchymal proteins in generated tumors was evaluated. We found that DHEA increased expression of E-cadherin and decreased N-cadherin, vimentin and Snail expression both in MD-MB-231 cells and in the formed tumors, possibly by DHEA-induced reversion of mesenchymal phenotype. These results were correlated with a tumor size reduction in mouse xenografts following DHEA administration either a week earlier or concurrent with breast cancer cells inoculation. In conclusion, DHEA could be useful in the treatment of breast cancer with mesenchymal phenotype.
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Affiliation(s)
- Zaira Colín-Val
- Departamento de Fisiología, Instituto Nacional de Cardiología "Ignacio Chávez", Ciudad de México, Mexico
| | | | - Criselda Mendoza-Milla
- Laboratorio de Biología Celular, Departamento de Fibrosis Pulmonar, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas", Mexico
| | - Erika Olivia Gómez
- Universidad Autónoma de la Ciudad de México, Colegio de Ciencias y Humanidades, Plantel San Lorenzo Tezonco, Mexico
| | - Claudia Huesca-Gómez
- Departamento de Fisiología, Instituto Nacional de Cardiología "Ignacio Chávez", Ciudad de México, Mexico
| | - Rebeca López-Marure
- Departamento de Fisiología, Instituto Nacional de Cardiología "Ignacio Chávez", Ciudad de México, Mexico.
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Corsini E, Galbiati V, Papale A, Kummer E, Pinto A, Serafini MM, Guaita A, Spezzano R, Caruso D, Marinovich M, Racchi M. Role of androgens in dhea-induced rack1 expression and cytokine modulation in monocytes. IMMUNITY & AGEING 2016; 13:20. [PMID: 27239218 PMCID: PMC4884617 DOI: 10.1186/s12979-016-0075-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 05/10/2016] [Indexed: 01/01/2023]
Abstract
Background Over the past fifteen years, we have demonstrated that cortisol and dehydroepiandrosterone (DHEA) have opposite effects on the regulation of protein kinase C (PKC) activity in the context of the immune system. The anti-glucocorticoid effect of DHEA is also related to the regulation of splicing of the glucocorticoid receptor (GR), promoting the expression of GRβ isoform, which acts as a negative dominant form on GRα activity. Moreover, it is very well known that DHEA can be metabolized to androgens like testosterone, dihydrotestosterone (DHT), and its metabolites 3α-diol and 3β-diol, which exert their function through the binding of the androgen receptor (AR). Based on this knowledge, and on early observation that castrated animals show results similar to those observed in old animals, the purpose of this study is to investigate the role of androgens and the androgen receptor (AR) in DHEA-induced expression of the PKC signaling molecule RACK1 (Receptor for Activated C Kinase 1) and cytokine production in monocytes. Results Here we demonstrated the ability of the anti-androgen molecule, flutamide, to counteract the stimulatory effects of DHEA on RACK1 and GRβ expression, and cytokine production. In both THP-1 cells and human peripheral blood mononuclear cells (PBMC), flutamide blocked the effects of DHEA, suggesting a role of the AR in these effects. As DHEA is not considered a direct AR agonist, we investigated the metabolism of DHEA in THP-1 cells. We evaluated the ability of testosterone, DHT, and androstenedione to induce RACK1 expression and cytokine production. In analogy to DHEA, an increase in RACK1 expression and in LPS-induced IL–8 and TNF–α production was observed after treatment with these selected androgens. Finally, the silencing of AR with siRNA completely prevented DHEA-induced RACK1 mRNA expression, supporting the idea that AR is involved in DHEA effects. Conclusions We demonstrated that the conversion of DHEA to active androgens, which act via AR, is a key mechanism in the effect of DHEA on RACK1 expression and monocyte activation. This data supports the existence of a complex hormonal balance in the control of immune modulation, which can be further studied in the context of immunosenescence and endocrinosenescence.
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Affiliation(s)
- Emanuela Corsini
- Laboratory of Toxicology, Department of Pharmacological and Biomolecular Sciences (DiSFeB), Università degli Studi di Milano, Milan, Italy
| | - Valentina Galbiati
- Laboratory of Toxicology, Department of Pharmacological and Biomolecular Sciences (DiSFeB), Università degli Studi di Milano, Milan, Italy
| | - Angela Papale
- Laboratory of Toxicology, Department of Pharmacological and Biomolecular Sciences (DiSFeB), Università degli Studi di Milano, Milan, Italy
| | - Elena Kummer
- Laboratory of Toxicology, Department of Pharmacological and Biomolecular Sciences (DiSFeB), Università degli Studi di Milano, Milan, Italy
| | - Antonella Pinto
- Department of Drug Sciences - Pharmacology Unit, University of Pavia, Viale Taramelli 14, Pavia, 27100 Italy
| | - Melania M Serafini
- Department of Drug Sciences - Pharmacology Unit, University of Pavia, Viale Taramelli 14, Pavia, 27100 Italy
| | | | - Roberto Spezzano
- Mass Spectrometry Laboratory "Giovanni Galli", DiSFeB, Università degli Studi di Milano, Milan, Italy
| | - Donatella Caruso
- Mass Spectrometry Laboratory "Giovanni Galli", DiSFeB, Università degli Studi di Milano, Milan, Italy
| | - Marina Marinovich
- Laboratory of Toxicology, Department of Pharmacological and Biomolecular Sciences (DiSFeB), Università degli Studi di Milano, Milan, Italy
| | - Marco Racchi
- Department of Drug Sciences - Pharmacology Unit, University of Pavia, Viale Taramelli 14, Pavia, 27100 Italy
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14
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Abstract
This review compares the biological and physiological function of Sigma receptors [σRs] and their potential therapeutic roles. Sigma receptors are widespread in the central nervous system and across multiple peripheral tissues. σRs consist of sigma receptor one (σ1R) and sigma receptor two (σ2R) and are expressed in numerous regions of the brain. The sigma receptor was originally proposed as a subtype of opioid receptors and was suggested to contribute to the delusions and psychoses induced by benzomorphans such as SKF-10047 and pentazocine. Later studies confirmed that σRs are non-opioid receptors (not an µ opioid receptor) and play a more diverse role in intracellular signaling, apoptosis and metabolic regulation. σ1Rs are intracellular receptors acting as chaperone proteins that modulate Ca2+ signaling through the IP3 receptor. They dynamically translocate inside cells, hence are transmembrane proteins. The σ1R receptor, at the mitochondrial-associated endoplasmic reticulum membrane, is responsible for mitochondrial metabolic regulation and promotes mitochondrial energy depletion and apoptosis. Studies have demonstrated that they play a role as a modulator of ion channels (K+ channels; N-methyl-d-aspartate receptors [NMDAR]; inositol 1,3,5 triphosphate receptors) and regulate lipid transport and metabolism, neuritogenesis, cellular differentiation and myelination in the brain. σ1R modulation of Ca2+ release, modulation of cardiac myocyte contractility and may have links to G-proteins. It has been proposed that σ1Rs are intracellular signal transduction amplifiers. This review of the literature examines the mechanism of action of the σRs, their interaction with neurotransmitters, pharmacology, location and adverse effects mediated through them.
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Affiliation(s)
- Colin G Rousseaux
- a Department of Pathology and Laboratory Medicine , University of Ottawa , Ottawa , ON , Canada and
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15
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Sorwell KG, Urbanski HF. Dehydroepiandrosterone and age-related cognitive decline. AGE (DORDRECHT, NETHERLANDS) 2010; 32:61-7. [PMID: 19711196 PMCID: PMC2829637 DOI: 10.1007/s11357-009-9113-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Accepted: 08/03/2009] [Indexed: 05/15/2023]
Abstract
In humans the circulating concentrations of dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS) decrease markedly during aging, and have been implicated in age-associated cognitive decline. This has led to the hypothesis that DHEA supplementation during aging may improve memory. In rodents, a cognitive anti-aging effect of DHEA and DHEAS has been observed but it is unclear whether this effect is mediated indirectly through conversion of these steroids to estradiol. Moreover, despite the demonstration of correlations between endogenous DHEA concentrations and cognitive ability in certain human patient populations, such correlations have yet to be convincingly demonstrated during normal human aging. This review highlights important differences between rodents and primates in terms of their circulating DHEA and DHEAS concentrations, and suggests that age-related changes within the human DHEA metabolic pathway may contribute to the relative inefficacy of DHEA replacement therapies in humans. The review also highlights the value of using nonhuman primates as a pragmatic animal model for testing the therapeutic potential of DHEA for age-associate cognitive decline in humans.
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Affiliation(s)
- Krystina G. Sorwell
- Division of Neuroscience, Oregon National Primate Research Center, 505 NW 185th Avenue, Beaverton, OR 97006 USA
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR 97239 USA
| | - Henryk F. Urbanski
- Division of Neuroscience, Oregon National Primate Research Center, 505 NW 185th Avenue, Beaverton, OR 97006 USA
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR 97239 USA
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16
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Baghbaderani BA, Mukhida K, Sen A, Kallos MS, Hong M, Mendez I, Behie LA. Bioreactor expansion of human neural precursor cells in serum-free media retains neurogenic potential. Biotechnol Bioeng 2010; 105:823-33. [PMID: 19882735 DOI: 10.1002/bit.22590] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Human neural precursor cells (hNPCs), harvested from somatic tissue and grown in vitro, may serve as a source of cells for cell replacement strategies aimed at treating neurodegenerative disorders such as Parkinson's disease (PD), Huntington's disease (HD), and intractable spinal cord pain. A crucial element in a robust clinical production method for hNPCs is a serum-free growth medium that can support the rapid expansion of cells while retaining their multipotency. Here, we report the development of a cell growth medium (PPRF-h2) for the expansion of hNPCs, achieving an overall cell-fold expansion of 10(13) over a period of 140 days in stationary culture which is significantly greater than other literature results. More importantly, hNPC expansion could be scaled-up from stationary culture to suspension bioreactors using this medium. Serial subculturing of the cells in suspension bioreactors resulted in an overall cell-fold expansion of 7.8 x 10(13) after 140 days. These expanded cells maintained their multipotency including the capacity to generate large numbers of neurons (about 60%). In view of our previous studies regarding successful transplantation of the bioreactor-expanded hNPCs in animal models of neurological disorders, these results have demonstrated that PPRF-h2 (containing dehydroepiandrosterone, basic fibroblast growth factor and human leukemia inhibitory factor) can successfully facilitate the production of large quantities of hNPCs with potential to be used in the treatment of neurodegenerative disorders.
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Affiliation(s)
- Behnam A Baghbaderani
- Pharmaceutical Production Research Facility (PPRF), Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada
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Kapoor VK, Dureja J, Chadha R. Synthetic drugs with anti-ageing effects. Drug Discov Today 2009; 14:899-904. [DOI: 10.1016/j.drudis.2009.07.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2008] [Revised: 07/16/2009] [Accepted: 07/17/2009] [Indexed: 01/30/2023]
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Abstract
Dehydroepiandrosterone (DHEA) and its sulfate (DHEAS) are hormones produced by the adrenal cortex that decline in concentration with age. Decreased DHEA levels are associated with age-related disease and oxidative stress but might be increased in younger adults by exercise. Studies are presented assessing the response of DHEA and DHEAS to varied-intensity exercise in older age. DHEA increased significantly in young adults (14.5 +/- 6.1 ng/ml rising to 21.1 +/- 7.5 ng/ml; p < .01), whereas DHEAS decreased significantly (2.56 +/- 1.11 microg/ml falling to 1.90 +/- 0.8 microg/ml; p < .05), after submaximal exercise. DHEA and DHEAS levels were significantly lower in older adults than in younger adults (p < .01), and there was no observed response of either hormone to exercise in older adults. Lipoprotein protein carbonylation is presented as a measure of oxidative status and significantly decreased in younger adults postexercise. Participants with higher DHEA postexercise had lower LDL protein carbonyl concentrations (Pearson's coefficient -.409, p < .05).
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19
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Chen C, Lang S, Zuo P, Yang N, Wang X. Treatment with Dehydroepiandrosterone Increases Peripheral Benzodiazepine Receptors of Mitochondria from Cerebral Cortex in d-Galactose-Induced Aged Rats. Basic Clin Pharmacol Toxicol 2008; 103:493-501. [DOI: 10.1111/j.1742-7843.2008.00288.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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20
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Functional mapping of the promoter region of the GNB2L1 human gene coding for RACK1 scaffold protein. Gene 2008; 430:17-29. [PMID: 19000751 DOI: 10.1016/j.gene.2008.10.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2008] [Revised: 10/02/2008] [Accepted: 10/04/2008] [Indexed: 11/22/2022]
Abstract
RACK1 (Receptor for Activated C Kinase 1) is a scaffold protein for different kinases and membrane receptors. Previously, we characterized an age-dependent decline of RACK1 protein expression which could be counteracted with DHEA (dehydroepiandrosterone) [Corsini, E., et al. 2002. In vivo dehydroepiandrosterone restores age-associated defects in the protein kinase C signal transduction pathway and related functional responses. J. Immunol. 168, 1753-1758. and Corsini, E., et al. 2005. Age-related decline in RACK-1 expression in human leukocytes is correlated to plasma levels of dehydroepiandrosterone. J. Leukoc. Biol. 77, 247-256.]. Hypothesizing a direct control of RACK1 expression by DHEA we studied the not yet characterized human promoter region of its coding gene GNB2L1. The FLOE (Fluorescently Labeled Oligonucleotide Extension) was used to map the transcription start site and a novel Gateway luciferase vector (GW luc basic; Del Vecchio, I., Zuccotti, A., Canneva, F., Lenzken, S.C., Racchi, M., 2007. Development of the first Gateway firefly luciferase vector and use of reverse transcriptase in FLOE (Fluorescently Labeled Oligonucleotide Extension) reactions. Plasmid 58, 269-274.) to obtain promoter region mutants. Human SH-SY5Y, THP1 and lymphoblastoid cells were used for transient transfections and treatments with lipopolysaccharide (LPS), phorbol myristate acetate (PMA), DHEA and cortisol (the first two molecules to differently activate NF-kB, a transcription complex able to regulate the murine Gnb2l1 gene expression, whereas DHEA and cortisol since they are known to be imbalanced during the aging and possess counteracting actions on the immune function). The primer extension demonstrated the existence of two alternative start sites of transcription respectively located at about 230 and 300 nt 5' of the Genbank mRNA entry for GNB2L1. Moreover, as a result of the luciferase study we were able to demonstrate that a little region of approximately 300 nt conserved sufficient elements for reporter expression. We also reported that the DHEA modulation of GNB2L1 endogenous expression could not be recapitulated with the luciferase assays. Indeed, the promoter was significantly modulated by means of LPS and PMA treatments but not using DHEA. Differently the use of cortisol led us to demonstrate a biologically significant decrease of luciferase activity only in the presence of a binding site for nuclear receptors of glucocorticoids. Interestingly, other binding sites for transcriptional factors were identified in silico: different c-Rel (NF-kB) and some cardiomyocitic specific cis-acting elements. All this data suggest that the DHEA mediated GNB2L1 regulation is modulated by distant elements (enhancers/silencers), whereas LPS, PMA and cortisol effect can act directly on the mapped GNB2L1 promoter. In conclusion we hypothesize that the imbalance between DHEA and cortisol during aging could be important in the previously demonstrated recovery of the RACK1 expression.
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21
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Effect of dehydroepiandrosterone (DHEA) on monoamine oxidase activity, lipid peroxidation and lipofuscin accumulation in aging rat brain regions. Biogerontology 2008; 9:235-46. [DOI: 10.1007/s10522-008-9133-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Accepted: 02/11/2008] [Indexed: 10/22/2022]
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22
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Harris R, Turan N, Kirk C, Ramsden D, Waring R. Effects of endocrine disruptors on dehydroepiandrosterone sulfotransferase and enzymes involved in PAPS synthesis: genomic and nongenomic pathways. ENVIRONMENTAL HEALTH PERSPECTIVES 2007; 115 Suppl 1:51-4. [PMID: 18174950 PMCID: PMC2174413 DOI: 10.1289/ehp.9365] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Accepted: 10/23/2006] [Indexed: 05/10/2023]
Abstract
BACKGROUND Sulfation plays an important role both in detoxification and in the control of steroid activity. Studies in rodents have shown that the conversion of dehydroepiandrosterone (DHEA) to DHEA-sulfate is involved in learning and the memory process. METHODS The effects of a range of plasticizers and related compounds commonly encountered in the environment were evaluated kinetically against human DHEA sulfotransferase (SULT 2A1) and by reverse transcriptase-polymerase chain reaction (RT-PCR) against several enzymes involved in the synthesis of the sulfotransferase cofactor adenosine 3'-phosphate 5'-phosphosulfate (PAPS). RESULTS We found that several of the chemicals acted as competitive inhibitors of SULT 2A1 (K(i) for 4-tert-octylphenol is 2.8 microM). Additionally, after treatment of TE 671 cells with 0.005-0.5 microM 4-n-octylphenol, bis(2-ethylhexyl)phthalate, and diisodecyl phthalate, real-time RT-PCR showed dose-dependent decreases in the steady-state mRNA levels of cysteine dioxygenase type I, sulfite oxidase, and 3'-phosphate 5'-phosphosulfate synthase I. CONCLUSIONS These data suggest that environmental contaminants may exert effects on neuronal function both by direct inhibition of sulfotransferase enzymes and by interrupting the supply of PAPS, which has wider implications for endocrine disruption and xenobiotic metabolism.
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Affiliation(s)
- Robert Harris
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, United Kingdom.
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23
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Patel MA, Modi HR, Katyare SS. Stimulation of oxidative energy metabolism in liver mitochondria from old and young rats by treatment with dehydroepiandrosterone (DHEA). A comparative study. AGE (DORDRECHT, NETHERLANDS) 2007; 29:41-49. [PMID: 19424829 PMCID: PMC2267683 DOI: 10.1007/s11357-007-9029-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2006] [Revised: 12/13/2006] [Accepted: 01/11/2007] [Indexed: 05/27/2023]
Abstract
Effects of treatment with DHEA (0.2 or 1.0 mg/kg body weight for 7 days) on oxidative energy metabolism of rat liver mitochondria from old (18-24 month old) and young (8-10 weeks old) male albino rats belonging to Charles-Foster strain were examined. Treatment with 1.0 mg DHEA resulted in increased body weights of the young rats without change in the liver weight. In the old animals the liver weight increased progressively with increasing dose of DHEA without affecting body weight. The state 3 respiration rates in liver mitochondria from old animals were, in general, lower than those in the young rats. The state 3 and state 4 respiration rates increased following DHEA treatment in dose-dependent manner bringing them close to values for young animals or beyond that with the effect being more pronounced at 1.0 mg dose. Treatment with DHEA also stimulated state 3 and state 4 respiration rates in young rats in dose-dependent manner. Contents of cytochrome aa(3), b and c + c(1) increased significantly in old animals in dose-dependent manner. In the young rats the lower dose (0.2 mg) of DHEA was more effective in bringing about a maximum increase in the contents of the cytochromes; the effect declined at the higher dose (1.0 mg). DHEA treatment also stimulated the mitochondrial ATPase activity in the old as well as in the young rats. The dehydrogenases activities were considerably low in the old rats compared to the values for the young animals. Treatment with DHEA stimulated dehydrogenases activities in old rats in dose-dependent manner bringing them close to values for the young animals or beyond. Treatment with lower dose (0.2 mg) of DHEA maximally stimulated dehydrogenases activities in young animals.
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Affiliation(s)
- Minal A. Patel
- Department of Biochemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat 390 002 India
| | - Hiren R. Modi
- Department of Biochemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat 390 002 India
| | - Surendra S. Katyare
- Department of Biochemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat 390 002 India
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24
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Abstract
Adrenarche, the prepubertal onset of adrenal production of dehydroepiandrosterone sulfate (DHEAS), is a distinctive aspect of the human life course. Yet its evolutionary origins remain unexplained. Production of DHEAS is associated with the development of the zona reticularis, a novel histological layer within the adrenal gland, derived from the fetal adrenal gland, and associated with primates more generally. Evidence that DHEAS is a neurosteroid, together with the fact that increases in DHEAS parallel patterns of cortical maturation from approximately age 6 years to the mid-20s, suggests that DHEAS may play an important role in extended brain maturation among humans. DHEAS has demonstrated effects on mood in humans, and acts at neuron receptor sites. I suggest three ways in which DHEAS may play a role in human brain maturation: 1) increasing activity of the amgydala; 2) increasing activity of the hippocampus; and 3) promoting synaptogenesis within the cortex. I propose that associated changes in fearfulness and anxiety, and memory, could act to increase social interaction with nonfamiliar individuals and shape cognitive development. Comparison with the African apes suggests that the timing of adrenarche in chimpanzees may be similar to that in humans, though the full course of age-related changes in DHEAS and their relationship to reproductive and brain maturation are not clear. The role of DHEAS as a physiological mechanism supporting increased brain development, extended life span, and decreased sexual dimorphism is most compatible with Kaplan et al.'s (2000) theory of the evolution of human life history and intergenerational transfers.
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Affiliation(s)
- Benjamin Campbell
- Department of Anthropology, Boston University, Boston, Massachusetts 02215, USA.
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25
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Patel MA, Katyare SS. Treatment with dehydroepiandrosterone (DHEA) stimulates oxidative energy metabolism in the cerebral mitochondria. Neurosci Lett 2006; 402:131-6. [PMID: 16630690 DOI: 10.1016/j.neulet.2006.03.057] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2006] [Revised: 03/24/2006] [Accepted: 03/25/2006] [Indexed: 11/16/2022]
Abstract
The content of the neurosteroids, dehydroepiandrosterone (DHEA) in the brain decreases with aging. Also the oxidative energy metabolism is known to decrease with aging. Hence we examined the effects of treatment with DHEA (0.2 or 1.0 mg/kg body weight for 7 days) on oxidative energy metabolism in brain mitochondria from old and young adult rats. State 3 respiration rates in brain mitochondria from old animals were considerably lower than those in young adults. Treatment with DHEA stimulated state 3 and state 4 respiration rates in both the groups of the animals in a dose-dependent manner. In the old rats following DHEA treatment, the state 3 respiration rates became comparable to or increased beyond those of untreated young adults. In contrast to the old rats, stimulatory effect of DHEA treatment was of greater magnitude in the young adults. However, at higher dose (1.0 mg) the effect declined. Cytochrome aa3 content in the brain mitochondria from old rats was significantly low but the content of cytochrome b was unchanged while the content of cytochromes c+c1 had increased. Treatment with DHEA increased the content of cytochrome aa3 and b in old as well as in young adult animals. Higher dose of DHEA (1.0 mg) had adverse effect on the content of cytochrome c+c1. DHEA treatment stimulated ATPase activity in a dose-dependent manner in young adult rats whereas in the old rats the effect on ATPase activity was marginal. Dehydrogenases activities were somewhat lower in the old rats. DHEA treatment stimulated mitochondrial dehydrogenases activities in both the groups. Results of our studies suggest that judicious use of DHEA treatment can improve oxidative energy metabolism parameters in brain mitochondria from young adult as well as old rats.
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Affiliation(s)
- Minal A Patel
- Department of Biochemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat 390 002, India
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Patel MA, Katyare SS. Dehydroepiandrosterone (DHEA) treatment stimulates oxidative energy metabolism in the cerebral mitochondria from developing rats. Int J Dev Neurosci 2006; 24:327-34. [PMID: 16777366 DOI: 10.1016/j.ijdevneu.2006.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2006] [Revised: 04/07/2006] [Accepted: 04/07/2006] [Indexed: 11/21/2022] Open
Abstract
Effects of treatment with dehydroepiandrosterone (DHEA) (0.2 or 1.0mg/kg body weight for 7 days) on oxidative energy metabolism in cerebral mitochondria from developing and young adult rats were examined. Treatment with DHEA did not change the body weight of developing rats but resulted in increase in the brain weight in 5 week group. In young adult rats the body weight increased following treatment with 1.0mg DHEA. State 3 and state 4 respiration rates with all the substrates increased following DHEA treatment, the effect being more pronounced in the developing rats. State 4 respiration rates were stimulated to variable extents. Contents of cytochromes aa(3) and b increased following DHEA treatment and once again the effect was more pronounced in the developing rats. DHEA treatment marginally changed the content of cytochromes c+c(1). In the developing rats the ATPase activity and the levels of dehydrogenases increased significantly by DHEA treatment. Results of our studies have shown that treatment with exogenous DHEA accelerates the process of maturation of cerebral mitochondria thus emphasizing the role of DHEA in brain development in postnatal life.
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Affiliation(s)
- Minal A Patel
- Department of Biochemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat 390002, India
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27
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Mo Q, Lu SF, Simon NG. Dehydroepiandrosterone and its metabolites: differential effects on androgen receptor trafficking and transcriptional activity. J Steroid Biochem Mol Biol 2006; 99:50-8. [PMID: 16524719 DOI: 10.1016/j.jsbmb.2005.11.011] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2005] [Accepted: 11/14/2005] [Indexed: 12/20/2022]
Abstract
Dehydroepiandrosterone (DHEA) is a multi-functional steroid that has been implicated in a broad range of biological effects in humans and rodents. Recent studies demonstrated that DHEA acts genomically through the androgen receptor (AR) in addition to its well-known effects on cell surface receptors. However, the relative contribution of DHEA and its major metabolites, including DHEA-Sulfate (DHEA-S), 7alpha-OH-DHEA, 7beta-OH-DHEA, 7-oxo-DHEA, androstenedione (Adione), and androstenediol (Adiol), in the production of genomic effects remains controversial, in part because the metabolism of DHEA varies in different cells and tissues. In the current study, the ability of DHEA and its metabolites to promote AR intracellular trafficking and regulate AR-mediated reporter gene expression, which are characteristic effects of androgens, was determined. Intracellular trafficking of AR-GFP protein was assessed in COS-7 cells while AR transcriptional activity was tested in CV-1 cells transiently co-transfected with AR expression plasmid and an MMTV-ARE-CAT reporter. The results demonstrated that DHEA, the 3beta-HSD metabolite Adione, and the 17beta-HSD metabolite Adiol, were androgenic. Each promoted AR-GFP intracellular trafficking, the formation of nuclear clusters, and AR-dependent transcriptional activity in a dose-dependent manner. In contrast, DHEA-S, 7alpha-OH-DHEA, 7beta-OH-DHEA, and 7-oxo-DHEA were ineffective and exhibited minimal androgenic activity, even at relatively high concentrations (10(-6) M). These results provide the first systematic comparison of the (i) androgenic activity of DHEA and its sulfated and hydroxylated metabolites, (ii) relative androgenicity of DHEA itself vs. the established androgens Adione and Adiol, and (iii) ability of DHEA and its major metabolites to promote AR-GFP intracellular trafficking. In addition to partitioning DHEA and its metabolites into compounds with (DHEA, Adione, Adiol) and without (DHEA-S, 7alpha-OH-DHEA, 7beta-OH-DHEA, and 7-oxo-DHEA) androgenic activity, the findings improve our understanding of the intracellular processes mediating the genomic effects of DHEA through AR.
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Affiliation(s)
- Qianxing Mo
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, United States
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Parsons TD, Kratz KM, Thompson E, Stanczyk FZ, Buckwalter JG. Dhea supplementation and cognition in postmenopausal women. Int J Neurosci 2006; 116:141-55. [PMID: 16393880 DOI: 10.1080/00207450500341506] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Previous work has suggested that DHEA supplementation may have adverse cognitive effects in elderly women. This article analyzed 24-h measurements of DHEA, DHEAS, and cortisol to determine if cognitive decrease with treatment is mediated by DHEA's impact on endogenous cortisol. It was found that DHEA administration increased cortisol at several hours during the day. In the treatment group, cortisol was positively associated with cognition at study completion. An increase in negative associations between DHEA(S) levels and cognition was found at completion. Increased cortisol does not explain the cognitive deficits associated with DHEA, suggesting a direct negative effect of exogenous DHEA on cognition.
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Affiliation(s)
- T D Parsons
- Department of Neurology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7025, USA. tparsons@neurology
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29
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Corsini E, Racchi M, Sinforiani E, Lucchi L, Viviani B, Rovati GE, Govoni S, Galli CL, Marinovich M. Age-related decline in RACK-1 expression in human leukocytes is correlated to plasma levels of dehydroepiandrosterone. J Leukoc Biol 2004; 77:247-56. [PMID: 15548575 DOI: 10.1189/jlb.0504268] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Aging is associated with remodeling of the immune system, contributing to increased incidence of infections, autoimmune diseases, and cancer among the elderly. Alterations in several signal transduction pathways have been reported to play an important role in immunosenescence. We show that peripheral blood leukocytes obtained from old donors (> or =65 years) have a significantly reduced expression of receptor for activated C kinase 1 (RACK-1), a protein required for protein kinase C (PKC)-beta signaling, as compared with young donors (< or =40 years), both in males and females. The decline in RACK-1 immunoboth in reactivity was age-related (Spearman correlation, r=-0.278, P=0.012). All leukocyte subpopulations, namely lympho-monocytes, granulocytes, and B and T cells, showed a similar defect. We also observed a direct correlation between circulating dehydroepiandrosterone (DHEA) and RACK-1 expression in leukocytes (Spearman correlation, r=0.388, P=0.001). Furthermore, in vitro treatment with DHEA resulted in increased RACK-1 expression in leukocytes and lymphocyte proliferation, confirming the role of this hormone in the modulation of its expression and immune functions. A relevant consequence of RACK-1-reduced expression was the observation that release of tumor necrosis factor alpha following lipopolysaccharide challenge and mitogen-induced lymphocye proliferation, which involves PKC-beta activation, was significantly reduced in elderly subjects. Overall, our findings contribute to the understanding of the complex process of immunosenescence and identify age-related loss in immunological responses as partially associated with decreased RACK-1 expression.
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Affiliation(s)
- Emanuela Corsini
- Laboratories of Toxicology, Department of Pharmacological Sciences, University of Milan, Via Balzaretti 9, 20133 Milan, Italy.
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30
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Mo Q, Lu SF, Hu S, Simon NG. DHEA and DHEA sulfate differentially regulate neural androgen receptor and its transcriptional activity. ACTA ACUST UNITED AC 2004; 126:165-72. [PMID: 15249140 DOI: 10.1016/j.molbrainres.2004.05.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2004] [Indexed: 11/15/2022]
Abstract
The mechanism of action of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S), two interconvertable neurosteroids, has not been fully characterized in the central nervous system (CNS). Previous studies demonstrated that DHEA was intrinsically androgenic, suggesting that it may act through a genomic pathway. However, it is not known whether DHEA-S also produces androgenic effects, an important question given that the concentration of DHEA-S in brain is some 7-12 times that of DHEA. The current study compared the potential androgenic effects of DHEA-S with DHEA by examining their capacity to induce two characteristic effects of an androgenic compound. These included the ability to (1) up-regulate neural androgen receptor (AR) protein level in mouse brain and immortalized GT1-7 hypothalamic cells and (2) assess their effect on reporter gene expression through AR in CV-1 cells cotransfected with pSG5-AR and pMMTV-ARE-CAT reporter. Semi-quantitative Western blot analysis showed that DHEA treatment significantly augmented AR in mouse brain and GT1-7 cells in a dose-dependent manner and that these effects were not blocked by trilostane (TRIL), a known 3beta-hydroxysteroid dehydrogenase inhibitor. DHEA also promoted AR-mediated reporter gene expression as a function of dose and the effect was comparable with or without the addition of TRIL. In contrast, DHEA-S treatment failed to increase AR level in the mouse brain or GT1-7 cells and modestly induced AR-mediated reporter gene expression only at substantially elevated concentrations compared to DHEA. The findings demonstrate that DHEA is capable of exerting androgenic effects through AR while the androgenicity of DHEA-S is negligible. The implications of the results for models of the mechanism of action of DHEA and its sulfate ester, DHEA-S, in the brain are considered.
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Affiliation(s)
- Qianxing Mo
- Department of Biological Sciences, Lehigh University, 111 Research Drive, Bethlehem, PA 18015, USA
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31
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You L. Steroid hormone biotransformation and xenobiotic induction of hepatic steroid metabolizing enzymes. Chem Biol Interact 2004; 147:233-46. [PMID: 15135080 DOI: 10.1016/j.cbi.2004.01.006] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2004] [Indexed: 11/30/2022]
Abstract
Normal reproductive development depends on the interplay of steroid hormones with their receptors at specific tissue sites. The concentrations of hormone ligands in the circulation and at target sites are maintained through coordinated regulation on steroid biosynthesis and degradation. Changed bioavailability of steroids, through alteration of steroidogenesis or biotransformation rates, leads to changes in endocrine function. Steroid hormones lose their receptor reactivity in most cases when they are bound to binding proteins, while metabolic conversion can result in either active or inactive metabolites. Hydroxylation by cytochrome P450 (CYP) enzymes and conjugation with glucuronide and sulfate are among the major hepatic pathways of steroid inactivation. The expression of these biotransformation enzymes can be induced by many xenobiotics. The barbiturate phenobarbital and the environmental toxicant 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) are among the well characterized inducers for the CYP 2B and 3A enzymes and selected conjugation enzymes. The induction of the steroid biotransformation enzymes is partly mediated through the activation of a group of nuclear receptors including the glucocorticoid receptor, the constitutive androstane receptor (CAR), the pregnane X receptor (PXR), and the peroxisome proliferator activated receptors (PPAR). Drug or chemical-induced increases in hepatic enzyme activities are often a basis for drug-drug interactions that lead to enhanced elimination and reduced therapeutic efficacy of steroidal drugs. The effects of enzyme induction on endogenous steroid clearance, along with its possible consequence, are less well understood. While enzyme induction by xenobiotics may increase clearance of the endogenous steroid, regulatory mechanisms for steroid homeostasis may adapt and compensate for altered clearance.
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Affiliation(s)
- Li You
- CIIT Centers for Health Research, 6 Davis Drive, P.O. Box 12137, Research Triangle Park, NC 27709-2137, USA.
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32
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Marklund N, Peltonen M, Nilsson TK, Olsson T. Low and high circulating cortisol levels predict mortality and cognitive dysfunction early after stroke. J Intern Med 2004; 256:15-21. [PMID: 15189361 DOI: 10.1111/j.1365-2796.2004.01334.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE Elevated cortisol levels are associated with confusion and poor outcome after stroke. Dehydroepiandrosterone sulphate (DS), the most abundant adrenal androgen may act as an anti-glucocorticoid. An altered regulation of these steroids may affect numerous brain functions, including neuronal survival. The purpose of this study was to investigate serum cortisol and DS levels and the cortisol/DS ratio early after stroke and relate our findings to the presence of disorientation and mortality. DESIGN Patients with acute ischaemic stroke (n = 88, 56 men and 32 women) admitted to a stroke unit were investigated with repeated clinical assessments and scores for degree of confusion, extent of paresis and level of functioning. Serum cortisol (C) and DS were measured on day 1 and/or day 4. Data for 28-day and 1-year mortality are presented. A control group of 65 age-matched healthy individuals was used. Multivariate analyses of mortality rates in the different tertiles or sixtiles of serum cortisol were performed with logistic regression, adjusting for age, sex, diabetes and level of consciousness. RESULTS There was no difference in serum cortisol levels on day 1 for stroke patients when compared with control group values. Initial cortisol levels were significantly higher in the patients with acute disorientation versus orientated patients (P < 0.05). Cortisol levels on day 1 were an independent predictor of 28-day mortality, and patients with low cortisol levels (<270 nmol L(-1)) and increased levels (>550 nmol L(-1)) both had an increased 1-year mortality. DS levels on day 1 were significantly elevated in stroke patients. CONCLUSION Hypercortisolism is associated with cognitive dysfunction early after ischaemic stroke. High and low circulating cortisol levels are associated with increased mortality after stroke. DS levels were not associated with clinical outcome.
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Affiliation(s)
- N Marklund
- Department of Neuroscience and Neurosurgery, Uppsala University, Uppsala University Hospital, Uppsala, Sweden.
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Abstract
Any hope of a fountain of youth to stop people from getting older is a long way off, with science just beginning to understand the complex genetic, physical, and hormonal causes of aging. Clearly, modem research has demonstrated that the concept of a hormonal fountain of youth is predominantly mythology. The best evidence supporting use of hormonal replacement is vitamin D and estrogen replacement to prevent hip fractures. Other than that, treatment should be limited to hormone replacement in persons who have endocrine disease.
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Affiliation(s)
- Mohamad H Horani
- Division of Geriatric Medicine, Saint Louis University School of Medicine, MO 63104, USA
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Hajszan T, MacLusky NJ, Leranth C. Dehydroepiandrosterone increases hippocampal spine synapse density in ovariectomized female rats. Endocrinology 2004; 145:1042-5. [PMID: 14645116 DOI: 10.1210/en.2003-1252] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This study tests the hypothesis that dehydroepiandrosterone (DHEA) stimulates formation of hippocampal CA1 spine synapses in ovariectomized rats. Subcutaneous injections of DHEA (1 mg/d for 2 d) increased CA1 spine synapse density by more than 50% compared with vehicle-injected animals. The effect of DHEA on CA1 synapse density was abolished by pretreatment with the nonsteroidal aromatase inhibitor, letrozole. DHEA treatment, with or without letrozole, had no detectable uterotrophic effect. These observations are consistent with the hypothesis that DHEA treatment may be capable of reversing the decline in hippocampal spine synapse density observed after loss of ovarian steroid hormone secretion. The blockade of the synaptic response to DHEA by letrozole, despite the lack of a uterotrophic response to this steroid, suggests that the hippocampal response to DHEA may be mediated via aromatization in the brain.
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Affiliation(s)
- Tibor Hajszan
- Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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