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Vassal M, Martins F, Monteiro B, Tambaro S, Martinez-Murillo R, Rebelo S. Emerging Pro-neurogenic Therapeutic Strategies for Neurodegenerative Diseases: A Review of Pre-clinical and Clinical Research. Mol Neurobiol 2024:10.1007/s12035-024-04246-w. [PMID: 38816676 DOI: 10.1007/s12035-024-04246-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 05/14/2024] [Indexed: 06/01/2024]
Abstract
The neuroscience community has largely accepted the notion that functional neurons can be generated from neural stem cells in the adult brain, especially in two brain regions: the subventricular zone of the lateral ventricles and the subgranular zone in the dentate gyrus of the hippocampus. However, impaired neurogenesis has been observed in some neurodegenerative diseases, particularly in Alzheimer's, Parkinson's, and Huntington's diseases, and also in Lewy Body dementia. Therefore, restoration of neurogenic function in neurodegenerative diseases emerges as a potential therapeutic strategy to counteract, or at least delay, disease progression. Considering this, the present study summarizes the different neuronal niches, provides a collection of the therapeutic potential of different pro-neurogenic strategies in pre-clinical and clinical research, providing details about their possible modes of action, to guide future research and clinical practice.
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Affiliation(s)
- Mariana Vassal
- Department of Medical Sciences, Institute of Biomedicine (iBiMED), University of Aveiro, Aveiro, Portugal
| | - Filipa Martins
- Department of Medical Sciences, Institute of Biomedicine (iBiMED), University of Aveiro, Aveiro, Portugal
| | - Bruno Monteiro
- Department of Medical Sciences, Institute of Biomedicine (iBiMED), University of Aveiro, Aveiro, Portugal
| | - Simone Tambaro
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - Ricardo Martinez-Murillo
- Neurovascular Research Group, Department of Translational Neurobiology, Cajal Institute (CSIC), Madrid, Spain
| | - Sandra Rebelo
- Department of Medical Sciences, Institute of Biomedicine (iBiMED), University of Aveiro, Aveiro, Portugal.
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2
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Hussain G, Akram R, Anwar H, Sajid F, Iman T, Han HS, Raza C, De Aguilar JLG. Adult neurogenesis: a real hope or a delusion? Neural Regen Res 2024; 19:6-15. [PMID: 37488837 PMCID: PMC10479850 DOI: 10.4103/1673-5374.375317] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/27/2023] [Accepted: 04/10/2023] [Indexed: 07/26/2023] Open
Abstract
Adult neurogenesis, the process of creating new neurons, involves the coordinated division, migration, and differentiation of neural stem cells. This process is restricted to neurogenic niches located in two distinct areas of the brain: the subgranular zone of the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle, where new neurons are generated and then migrate to the olfactory bulb. Neurogenesis has been thought to occur only during the embryonic and early postnatal stages and to decline with age due to a continuous depletion of neural stem cells. Interestingly, recent years have seen tremendous progress in our understanding of adult brain neurogenesis, bridging the knowledge gap between embryonic and adult neurogenesis. Here, we discuss the current status of adult brain neurogenesis in light of what we know about neural stem cells. In this notion, we talk about the importance of intracellular signaling molecules in mobilizing endogenous neural stem cell proliferation. Based on the current understanding, we can declare that these molecules play a role in targeting neurogenesis in the mature brain. However, to achieve this goal, we need to avoid the undesired proliferation of neural stem cells by controlling the necessary checkpoints, which can lead to tumorigenesis and prove to be a curse instead of a blessing or hope.
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Affiliation(s)
- Ghulam Hussain
- Neurochemicalbiology and Genetics Laboratory (NGL), Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Punjab, Pakistan
| | - Rabia Akram
- Neurochemicalbiology and Genetics Laboratory (NGL), Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Punjab, Pakistan
| | - Haseeb Anwar
- Neurochemicalbiology and Genetics Laboratory (NGL), Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Punjab, Pakistan
| | - Faiqa Sajid
- Neurochemicalbiology and Genetics Laboratory (NGL), Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Punjab, Pakistan
| | - Tehreem Iman
- Neurochemicalbiology and Genetics Laboratory (NGL), Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Punjab, Pakistan
| | - Hyung Soo Han
- Department of Physiology, School of Medicine, Clinical Omics Institute, Kyungpook National University, Daegu, Korea
| | - Chand Raza
- Department of Zoology, Faculty of Chemistry and Life Sciences, Government College University, Lahore, Pakistan
| | - Jose-Luis Gonzalez De Aguilar
- INSERM, U1118, Mécanismes Centraux et Péripheriques de la Neurodégénérescence, Strasbourg, France, Université de Strasbourg, Strasbourg, France
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3
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Kraemer RR, Kraemer BR. The effects of peripheral hormone responses to exercise on adult hippocampal neurogenesis. Front Endocrinol (Lausanne) 2023; 14:1202349. [PMID: 38084331 PMCID: PMC10710532 DOI: 10.3389/fendo.2023.1202349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Accepted: 11/02/2023] [Indexed: 12/18/2023] Open
Abstract
Over the last decade, a considerable amount of new data have revealed the beneficial effects of exercise on hippocampal neurogenesis and the maintenance or improvement of cognitive function. Investigations with animal models, as well as human studies, have yielded novel understanding of the mechanisms through which endocrine signaling can stimulate neurogenesis, as well as the effects of exercise on acute and/or chronic levels of these circulating hormones. Considering the effects of aging on the decline of specific endocrine factors that affect brain health, insights in this area of research are particularly important. In this review, we discuss how different forms of exercise influence the peripheral production of specific endocrine factors, with particular emphasis on brain-derived neurotrophic factor, growth hormone, insulin-like growth factor-1, ghrelin, estrogen, testosterone, irisin, vascular endothelial growth factor, erythropoietin, and cortisol. We also describe mechanisms through which these endocrine responses to exercise induce cellular changes that increase hippocampal neurogenesis and improve cognitive function.
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Affiliation(s)
- Robert R. Kraemer
- Department of Kinesiology and Health Studies, Southeastern Louisiana University, Hammond, LA, United States
| | - Bradley R. Kraemer
- Department of Biological Sciences, University of Alabama in Huntsville, Huntsville, AL, United States
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4
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Zamir A, Ben Zeev T, Levi C, Einstein O, Ratamess NA, van Praag H, Hoffman JR. The effect of supraphysiological dose of nandrolone decanoate administration on the inflammatory, neurotrophin and behavioral response in adult and old male mice. Horm Behav 2023; 156:105444. [PMID: 38344953 DOI: 10.1016/j.yhbeh.2023.105444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 10/16/2023] [Accepted: 10/18/2023] [Indexed: 02/15/2024]
Abstract
This study examined the effect of 6 weeks of supraphysiological nandrolone decanoate (ND) administration in adult mice (7 months) on cognitive function and neuroinflammation during aging. Male C57BL/6 mice were randomized into ND (10 mg·kg-1·wk-1) or control (CTL) groups. Half of the mice were tested at a young (Y) age (ND-Y and CTL-Y), 1 week following final ND administration, while the remaining mice were tested at 16 months (O) (ND-O and CTL-O). Learning and memory were better in young mice compared to older mice, regardless of treatment. ND-O displayed decreased anxiety as compared to all other groups. TNFα and IL1β expression were higher in older mice, regardless of treatment. ND administration in young mice appeared to attenuate the neuroinflammatory response in aging mice as evidenced by decreased COX2, IL-4 and increased IL-10 expression in ND-O compared to CTL-O. BDNF AR and ER expression increased in ND-O compared to CTL-O. Results of the study indicated that supraphysiological ND administration had no negative effect on learning and memory but may attenuate anxiety in older mice. In addition, ND administration in young adult mice may attenuate the inflammatory response during aging, which may be related to elevations in both AR and ER expression.
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Affiliation(s)
- A Zamir
- Department of Physical Therapy, School of Health Sciences, Ariel University, Israel
| | - T Ben Zeev
- Department of Physical Therapy, School of Health Sciences, Ariel University, Israel
| | - C Levi
- Department of Physical Therapy, School of Health Sciences, Ariel University, Israel
| | - O Einstein
- Department of Physical Therapy, School of Health Sciences, Ariel University, Israel
| | - N A Ratamess
- Department of Kinesiology and Health Sciences, The College of New Jersey, USA
| | - H van Praag
- Stiles-Nicholson Brain Institute, Charles E. Schmidt College of Medicine, Florida Atlantic University, USA
| | - J R Hoffman
- Department of Physical Therapy, School of Health Sciences, Ariel University, Israel.
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Zhang L, Tang W, Ouyang Y, Zhang M, Li R, Sun L, Liu C, Yu H. N-palmitoylethanolamine modulates hippocampal neuroplasticity in rats with stress-induced depressive behavior phenotype. Eur J Pharmacol 2023; 957:176041. [PMID: 37673363 DOI: 10.1016/j.ejphar.2023.176041] [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: 05/30/2023] [Revised: 08/31/2023] [Accepted: 08/31/2023] [Indexed: 09/08/2023]
Abstract
Bioactive lipid mediator N-palmitoylethanolamide (PEA) is an endocannabinoid-like molecule. Based on our previous data, this study aimed to further investigate the antidepressant property of PEA via the peroxisome proliferator-activated receptor alpha (PPARα) pathway, focusing on the intervention of PEA on hippocampal neuroplasticity. Behavioral tests were performed in rats induced by unpredictable chronic mild stress (uCMS) in the last week of the experiment, and then the brain tissue samples were retained for subsequent immunohistochemical detection and Western blot analysis. In vitro, the apoptosis of HT22 cells induced by CORT and apoptosis-related proteins were detected by Hoechst staining and Western blot, respectively. The results showed that PEA ameliorated the depression-like phenotype in rats induced by uCMS, prevented the uCMS-induced reduction in the number of BrdU-positive cells, and increased BrdU/NeuN co-localization in the hippocampus, and upregulated the levels of synapse associated protein NCAM, MAP2, SYN and PSD95 in the hippocampus. Hoechst staining results showed that PEA significantly increased the CORT-induced reduction in the number of hippocampal neurons. Western blot analysis showed that PEA decreased the expression of caspase-3 and c-caspase-3, and increased the ratio of Bcl-2/Bax in CORT-induced HT22 cells. MK886, a PPARα antagonist, partially or completely reversed these effects. In conclusion, the therapeutic potential of PEA for depressive mood disorders may be through targeting the hippocampal neuroplasticity, including increasing adult neurogenesis and synaptic plasticity, as well as down-regulated neuronal apoptosis, to remodel hippocampal circuitries upon functional integration and PPARα pathway may be involved in this process.
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Affiliation(s)
- Luwen Zhang
- Department of Functional Science, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China; Experimental Teaching Center of Morphology, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China
| | - Wenjuan Tang
- Department of Functional Science, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China; Experimental Teaching Center of Morphology, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China
| | - Yinan Ouyang
- College of Pharmacy, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China
| | - Miao Zhang
- Department of Functional Science, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China; Experimental Teaching Center of Morphology, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China
| | - Ruirui Li
- Department of Functional Science, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China; Experimental Teaching Center of Morphology, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China
| | - Lianping Sun
- Department of Functional Science, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China; Experimental Teaching Center of Morphology, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China
| | - Chao Liu
- Department of Neurology, Yanbian University Affiliated Hospital, Juzi, Street 1327, Yanji, 133002, Jilin, PR China
| | - Hailing Yu
- Department of Functional Science, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China; Experimental Teaching Center of Morphology, College of Medicine, Yanbian University, Park Street 977, Yanji, 133002, Jilin, PR China.
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Bobotis BC, Braniff O, Gargus M, Akinluyi ET, Awogbindin IO, Tremblay MÈ. Sex differences of microglia in the healthy brain from embryonic development to adulthood and across lifestyle influences. Brain Res Bull 2023; 202:110752. [PMID: 37652267 DOI: 10.1016/j.brainresbull.2023.110752] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 08/15/2023] [Accepted: 08/28/2023] [Indexed: 09/02/2023]
Abstract
Microglia, the central nervous system innate immune cells, play a critical role in maintaining a homeostatic environment in the brain throughout life. These cells exhibit an impressive range of functions and characteristics that help to ensure proper functioning of the brain. Notably, microglia can present differences in their genetic and physical traits, which can be influenced by a range of factors, including age, environmental exposures, disease, and sex. Remarkably, microglia have been found to express receptors for sex hormones, suggesting that these hormones may play a role in modulating microglial behavior and potentially contribute to sex differences. Additionally, sex-chromosomal factors were shown to impact microglial genetics and functioning. In this review, we will examine how microglial responses in homeostasis are impacted by their interaction with sex hormones and sex chromosomes. Specifically, our investigation will focus on examining this interaction from embryonic development to adulthood, and the influence of lifestyle elements on various microglial features, including density and distribution, morphology, transcriptome, and proteome.
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Affiliation(s)
| | - Olivia Braniff
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Makenna Gargus
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Elizabeth Toyin Akinluyi
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Department of Pharmacology and Therapeutics, Afe Babalola University, Ado-Ekiti, Nigeria
| | - Ifeoluwa Oluleke Awogbindin
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Neuroimmunology Group, Molecular Drug Metabolism and Toxicology Laboratory, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Neurosciences Axis, Centre de Recherche du CHU de Québec, Université Laval, Québec, QC, Canada; Department of Molecular Medicine, Université Laval, Québec, QC, Canada; Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada; Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada.
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7
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Koszałka A, Lustyk K, Pytka K. Sex-dependent differences in animal cognition. Neurosci Biobehav Rev 2023; 153:105374. [PMID: 37634555 DOI: 10.1016/j.neubiorev.2023.105374] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/17/2023] [Accepted: 08/23/2023] [Indexed: 08/29/2023]
Abstract
The differences in cognitive processes driven by biological sex are the issues that have gotten growing attention recently. Considering the increasing population suffering from various cognitive impairments and the development of therapeutic strategies, it is essential that we recognize the mechanisms responsible for discrepancies observed in male and female learning and memory functions. In this review, we discuss recent reports from preclinical studies on rodents regarding selected cognitive domains to explore the state of knowledge on sex-dependent differences and point to challenges encountered during such research. We focus on spatial, recognition, and emotional memory, as well as on executive functions, such as attention, cognitive flexibility, and working memory. This review will help to acknowledge sex-related differences in cognition and indicate some fields that lack sufficient data.
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Affiliation(s)
- Aleksandra Koszałka
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Pharmacodynamics, Medyczna 9, 30-688 Krakow, Poland; Jagiellonian University Medical College, Doctoral School of Medical and Health Sciences, Św. Łazarza 16, 31-530 Krakow, Poland
| | - Klaudia Lustyk
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Pharmacodynamics, Medyczna 9, 30-688 Krakow, Poland
| | - Karolina Pytka
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Pharmacodynamics, Medyczna 9, 30-688 Krakow, Poland.
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8
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Saleki K, Banazadeh M, Saghazadeh A, Rezaei N. Aging, testosterone, and neuroplasticity: friend or foe? Rev Neurosci 2022; 34:247-273. [PMID: 36017670 DOI: 10.1515/revneuro-2022-0033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 07/03/2022] [Indexed: 11/15/2022]
Abstract
Neuroplasticity or neural plasticity implicates the adaptive potential of the brain in response to extrinsic and intrinsic stimuli. The concept has been utilized in different contexts such as injury and neurological disease. Neuroplasticity mechanisms have been classified into neuroregenerative and function-restoring processes. In the context of injury, neuroplasticity has been defined in three post-injury epochs. Testosterone plays a key yet double-edged role in the regulation of several neuroplasticity alterations. Research has shown that testosterone levels are affected by numerous factors such as age, stress, surgical procedures on gonads, and pharmacological treatments. There is an ongoing debate for testosterone replacement therapy (TRT) in aging men; however, TRT is more useful in young individuals with testosterone deficit and more specific subgroups with cognitive dysfunction. Therefore, it is important to pay early attention to testosterone profile and precisely uncover its harms and benefits. In the present review, we discuss the influence of environmental factors, aging, and gender on testosterone-associated alterations in neuroplasticity, as well as the two-sided actions of testosterone in the nervous system. Finally, we provide practical insights for further study of pharmacological treatments for hormonal disorders focusing on restoring neuroplasticity.
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Affiliation(s)
- Kiarash Saleki
- Student Research Committee, Babol University of Medical Sciences, 47176 47745 Babol, Iran.,USERN Office, Babol University of Medical Sciences, 47176 47745 Babol, Iran.,Systematic Review and Meta-analysis Expert Group (SRMEG), Universal Scientific Education and Research Network (USERN), 14197 33151 Tehran, Iran
| | - Mohammad Banazadeh
- Systematic Review and Meta-analysis Expert Group (SRMEG), Universal Scientific Education and Research Network (USERN), 14197 33151 Tehran, Iran.,Pharmaceutical Sciences and Cosmetic Products Research Center, Kerman University of Medical Sciences, 76169 13555 Kerman, Iran
| | - Amene Saghazadeh
- Systematic Review and Meta-analysis Expert Group (SRMEG), Universal Scientific Education and Research Network (USERN), 14197 33151 Tehran, Iran.,Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, 14197 33151 Tehran, Iran
| | - Nima Rezaei
- Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, 14197 33151 Tehran, Iran.,Department of Immunology, School of Medicine, Tehran University of Medical Sciences, 14176 13151 Tehran, Iran.,Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), 14197 33151 Tehran, Iran
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9
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Immature excitatory neurons in the amygdala come of age during puberty. Dev Cogn Neurosci 2022; 56:101133. [PMID: 35841648 PMCID: PMC9289873 DOI: 10.1016/j.dcn.2022.101133] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/23/2022] [Accepted: 07/08/2022] [Indexed: 11/21/2022] Open
Abstract
The human amygdala is critical for emotional learning, valence coding, and complex social interactions, all of which mature throughout childhood, puberty, and adolescence. Across these ages, the amygdala paralaminar nucleus (PL) undergoes significant structural changes including increased numbers of mature neurons. The PL contains a large population of immature excitatory neurons at birth, some of which may continue to be born from local progenitors. These progenitors disappear rapidly in infancy, but the immature neurons persist throughout childhood and adolescent ages, indicating that they develop on a protracted timeline. Many of these late-maturing neurons settle locally within the PL, though a small subset appear to migrate into neighboring amygdala subnuclei. Despite its prominent growth during postnatal life and possible contributions to multiple amygdala circuits, the function of the PL remains unknown. PL maturation occurs predominately during late childhood and into puberty when sex hormone levels change. Sex hormones can promote developmental processes such as neuron migration, dendritic outgrowth, and synaptic plasticity, which appear to be ongoing in late-maturing PL neurons. Collectively, we describe how the growth of late-maturing neurons occurs in the right time and place to be relevant for amygdala functions and neuropsychiatric conditions.
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Sheppard PAS, Puri TA, Galea LAM. Sex Differences and Estradiol Effects in MAPK and Akt Cell Signaling across Subregions of the Hippocampus. Neuroendocrinology 2022; 112:621-635. [PMID: 34407537 DOI: 10.1159/000519072] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 08/16/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Rapid effects of estrogens within the hippocampus of rodents are dependent upon cell-signaling cascades, and activation of these cascades by estrogens varies by sex. Whether these pathways are rapidly activated within the dentate gyrus (DG) and CA1 by estrogens across sex and the anatomical longitudinal axis has been overlooked. METHODS Gonadally intact female and male rats were given either vehicle or physiological systemic low (1.1 µg/kg) or high (37.3 µg/kg) doses of 17β-estradiol 30 min prior to tissue collection. To control for the effects of circulating estrogens, an additional group of female rats was ovariectomized (OVX) and administered 17β-estradiol. Brains were extracted, and tissue punches of the CA1 and DG were taken along the longitudinal hippocampal axis (dorsal and ventral) and analyzed for key mitogen-activated protein kinase (MAPK) and protein kinase B (Akt) cascade phosphoproteins. RESULTS Intact females had higher Akt pathway phosphoproteins (pAkt, pGSK-3β, and pp70S6K) than males in the DG (dorsal and ventral) and lower pERK1/2 in the dorsal DG. Most effects of 17β-estradiol on cell signaling occurred in OVX animals. In OVX animals, 17β-estradiol increased cell signaling of MAPK and Akt phosphoproteins (pERK1/2, pJNK, pAkt, and pGSK-3β) in the CA1 and pERK1/2 and pJNK DG. DISCUSSION/CONCLUSIONS Systemic 17β-estradiol treatment rapidly alters phosphoprotein levels in the hippocampus, dependent on reproductive status, and intact females have greater expression of Akt phosphoproteins than that in intact males in the DG. These findings shed light on underlying mechanisms of sex differences in hippocampal function and response to interventions that affect MAPK or Akt signaling.
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Affiliation(s)
- Paul A S Sheppard
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Tanvi A Puri
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada
| | - Liisa A M Galea
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada
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11
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Kuwahara N, Nicholson K, Isaacs L, MacLusky NJ. Androgen Effects on Neural Plasticity. ANDROGENS: CLINICAL RESEARCH AND THERAPEUTICS 2021; 2:216-230. [PMID: 35024693 PMCID: PMC8744448 DOI: 10.1089/andro.2021.0022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 10/24/2021] [Indexed: 12/20/2022]
Abstract
Androgens are synthesized in the brain, gonads, and adrenal glands, in both sexes, exerting physiologically important effects on the structure and function of the central nervous system. These effects may contribute to the incidence and progression of neurological disorders such as autism spectrum disorder, schizophrenia, and Alzheimer's disease, which occur at different rates in males and females. This review briefly summarizes the current state of knowledge with respect to the neuroplastic effects of androgens, with particular emphasis on the hippocampus, which has been the focus of much of the research in this field.
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Affiliation(s)
- Nariko Kuwahara
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Kate Nicholson
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Lauren Isaacs
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Neil J. MacLusky
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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12
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Hodges TE, Puri TA, Blankers SA, Qiu W, Galea LAM. Steroid hormones and hippocampal neurogenesis in the adult mammalian brain. VITAMINS AND HORMONES 2021; 118:129-170. [PMID: 35180925 DOI: 10.1016/bs.vh.2021.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Hippocampal neurogenesis persists across the lifespan in many species, including rodents and humans, and is associated with cognitive performance and the pathogenesis of neurodegenerative disease and psychiatric disorders. Neurogenesis is modulated by steroid hormones that change across development and differ between the sexes in rodents and humans. Here, we discuss the effects of stress and glucocorticoid exposure from gestation to adulthood as well as the effects of androgens and estrogens in adulthood on neurogenesis in the hippocampus. Throughout the review we highlight sex differences in the effects of steroid hormones on neurogenesis and how they may relate to hippocampal function and disease. These data highlight the importance of examining age and sex when evaluating the effects of steroid hormones on hippocampal neurogenesis.
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Affiliation(s)
- Travis E Hodges
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada; Department of Psychology, University of British Columbia, Vancouver, BC, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Tanvi A Puri
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Samantha A Blankers
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Wansu Qiu
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Liisa A M Galea
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada; Department of Psychology, University of British Columbia, Vancouver, BC, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada.
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Blankers SA, Galea LA. Androgens and Adult Neurogenesis in the Hippocampus. ANDROGENS: CLINICAL RESEARCH AND THERAPEUTICS 2021; 2:203-215. [PMID: 35024692 PMCID: PMC8744005 DOI: 10.1089/andro.2021.0016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 08/19/2021] [Indexed: 11/12/2022]
Abstract
Adult neurogenesis in the hippocampus is modulated by steroid hormones, including androgens, in male rodents. In this review, we summarize research showing that chronic exposure to androgens, such as testosterone and dihydrotestosterone, enhances the survival of new neurons in the dentate gyrus of male, but not female, rodents, via the androgen receptor. However, the neurogenesis promoting the effect of androgens in the dentate gyrus may be limited to younger adulthood as it is not evident in middle-aged male rodents. Although direct exposure to androgens in adult or middle age does not significantly influence neurogenesis in female rodents, the aromatase inhibitor letrozole enhances neurogenesis in the hippocampus of middle-aged female mice. Unlike other androgens, androgenic anabolic steroids reduce neurogenesis in the hippocampus of male rodents. Collectively, the research indicates that the ability of androgens to enhance hippocampal neurogenesis in adult rodents is dependent on dose, androgen type, sex, duration, and age. We discuss these findings and how androgens may be influencing neuroprotection, via neurogenesis in the hippocampus, in the context of health and disease.
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Affiliation(s)
- Samantha A. Blankers
- Graduate Program in Neuroscience, The University of British Columbia, Vancouver, Canada
- Djavad Mowafaghian Centre for Brain Health, The University of British Columbia, Vancouver, Canada
| | - Liisa A.M. Galea
- Graduate Program in Neuroscience, The University of British Columbia, Vancouver, Canada
- Djavad Mowafaghian Centre for Brain Health, The University of British Columbia, Vancouver, Canada
- Department of Psychology, The University of British Columbia, Vancouver, Canada
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14
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Nawarawong NN, Thompson KR, Guerin SP, Anasooya Shaji C, Peng H, Nixon K. Reactive, Adult Neurogenesis From Increased Neural Progenitor Cell Proliferation Following Alcohol Dependence in Female Rats. Front Neurosci 2021; 15:689601. [PMID: 34594180 PMCID: PMC8477003 DOI: 10.3389/fnins.2021.689601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 08/16/2021] [Indexed: 11/25/2022] Open
Abstract
Hippocampal neurodegeneration is a consequence of excessive alcohol drinking in alcohol use disorders (AUDs), however, recent studies suggest that females may be more susceptible to alcohol-induced brain damage. Adult hippocampal neurogenesis is now well accepted to contribute to hippocampal integrity and is known to be affected by alcohol in humans as well as in animal models of AUDs. In male rats, a reactive increase in adult hippocampal neurogenesis has been observed during abstinence from alcohol dependence, a phenomenon that may underlie recovery of hippocampal structure and function. It is unknown whether reactive neurogenesis occurs in females. Therefore, adult female rats were exposed to a 4-day binge model of alcohol dependence followed by 7 or 14 days of abstinence. Immunohistochemistry (IHC) was used to assess neural progenitor cell (NPC) proliferation (BrdU and Ki67), the percentage of increased NPC activation (Sox2+/Ki67+), the number of immature neurons (NeuroD1), and ectopic dentate gyrus granule cells (Prox1). On day seven of abstinence, ethanol-treated females showed a significant increase in BrdU+ and Ki67+ cells in the subgranular zone of the dentate gyrus (SGZ), as well as greater activation of NPCs (Sox2+/Ki67+) into active cycling. At day 14 of abstinence, there was a significant increase in the number of immature neurons (NeuroD1+) though no evidence of ectopic neurogenesis according to either NeuroD1 or Prox1 immunoreactivity. Altogether, these data suggest that alcohol dependence produces similar reactive increases in NPC proliferation and adult neurogenesis. Thus, reactive, adult neurogenesis may be a means of recovery for the hippocampus after alcohol dependence in females.
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Affiliation(s)
- Natalie N Nawarawong
- College of Pharmacy, The University of Texas at Austin, Austin, TX, United States
| | - K Ryan Thompson
- College of Pharmacy, The University of Texas at Austin, Austin, TX, United States
| | - Steven P Guerin
- College of Pharmacy, The University of Texas at Austin, Austin, TX, United States
| | | | - Hui Peng
- Division of Pharmacology & Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX, United States
| | - Kimberly Nixon
- College of Pharmacy, The University of Texas at Austin, Austin, TX, United States
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Saengmearnuparp T, Lojanapiwat B, Chattipakorn N, Chattipakorn S. The connection of 5-alpha reductase inhibitors to the development of depression. Biomed Pharmacother 2021; 143:112100. [PMID: 34479019 DOI: 10.1016/j.biopha.2021.112100] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/20/2021] [Accepted: 08/23/2021] [Indexed: 11/16/2022] Open
Abstract
Recent literature connects 5-alpha reductase inhibitors (5-ARIs) with neuropsychiatric adverse effects. Several clinical studies have indicated that former 5-ARIs users had a higher incidence of depressive symptoms and neuropsychiatric side effects than non-users. However, the underlying mechanisms involved in the depression in former 5-ARIs patients, a condition known as "post finasteride syndrome (PFS)", are not thoroughly understood. This review aims to summarize and discuss the association between 5-ARIs and depression as well as possible mechanisms. We used PubMed search terms including "depression", "depressive symptoms", "MDD", "anxiety", or "suicidal idea", and "5-alpha reductase inhibitors", "finasteride", "dutasteride", "5-ARIs". All relevant articles from in vivo and clinical studies from 2002 to 2021 were carefully reviewed. Any contradictory findings were included and debated. The potential mechanisms that link 5-ARIs and depression include alteration in neuroactive steroids, dopaminergic dysfunction, reduced hippocampal neurogenesis, increased neuroinflammation, alteration of the HPA axis, and epigenetic modifications. From this review, we hope to provide information for future studies based on animal experiments, and potential therapeutic strategies for depressive patients with PFS.
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Affiliation(s)
| | - Bannakij Lojanapiwat
- Department of Surgery, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Nipon Chattipakorn
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Siriporn Chattipakorn
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai 50200, Thailand; Department of Oral Biology and Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai 50200, Thailand.
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16
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Androgen Affects the Inhibitory Avoidance Memory by Primarily Acting on Androgen Receptor in the Brain in Adolescent Male Rats. Brain Sci 2021; 11:brainsci11020239. [PMID: 33672867 PMCID: PMC7918178 DOI: 10.3390/brainsci11020239] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 11/17/2022] Open
Abstract
Adolescence is the critical postnatal stage for the action of androgen in multiple brain regions. Androgens can regulate the learning/memory functions in the brain. It is known that the inhibitory avoidance test can evaluate emotional memory and is believed to be dependent largely on the amygdala and hippocampus. However, the effects of androgen on inhibitory avoidance memory have never been reported in adolescent male rats. In the present study, the effects of androgen on inhibitory avoidance memory and on androgen receptor (AR)-immunoreactivity in the amygdala and hippocampus were studied using behavioral analysis, Western blotting and immunohistochemistry in sham-operated, orchiectomized, orchiectomized + testosterone or orchiectomized + dihydrotestosterone-administered male adolescent rats. Orchiectomized rats showed significantly reduced time spent in the illuminated box after 30 min (test 1) or 24 h (test 2) of electrical foot-shock (training) and reduced AR-immunoreactivity in amygdala/hippocampal cornu Ammonis (CA1) in comparison to those in sham-operated rats. Treatment of orchiectomized rats with either non-aromatizable dihydrotestosterone or aromatizable testosterone were successfully reinstated these effects. Application of flutamide (AR-antagonist) in intact adolescent rats exhibited identical changes to those in orchiectomized rats. These suggest that androgens enhance the inhibitory avoidance memory plausibly by binding with AR in the amygdala and hippocampus.
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Acosta H, Tuulari JJ, Kantojärvi K, Lewis JD, Hashempour N, Scheinin NM, Lehtola SJ, Fonov VS, Collins DL, Evans A, Parkkola R, Lähdesmäki T, Saunavaara J, Merisaari H, Karlsson L, Paunio T, Karlsson H. A variation in the infant oxytocin receptor gene modulates infant hippocampal volumes in association with sex and prenatal maternal anxiety. Psychiatry Res Neuroimaging 2021; 307:111207. [PMID: 33168330 DOI: 10.1016/j.pscychresns.2020.111207] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 10/01/2020] [Accepted: 10/12/2020] [Indexed: 11/28/2022]
Abstract
Genetic variants in the oxytocin receptor (OTR) have been linked to distinct social phenotypes, psychiatric disorders and brain volume alterations in adults. However, to date, it is unknown how OTR genotype shapes prenatal brain development and whether it interacts with maternal prenatal environmental risk factors on infant brain volumes. In 105 Finnish mother-infant dyads (44 female, 11-54 days old), the association of offspring OTR genotype rs53576 and its interaction with prenatal maternal anxiety (revised Symptom Checklist 90, gestational weeks 14, 24, 34) on infant bilateral amygdalar, hippocampal and caudate volumes were probed. A sex-specific main effect of rs53576 on infant left hippocampal volumes was observed. In boys compared to girls, left hippocampal volumes were significantly larger in GG-homozygotes compared to A-allele carriers. Furthermore, genotype rs53576 and prenatal maternal anxiety significantly interacted on right hippocampal volumes irrespective of sex. Higher maternal anxiety was associated both with larger hippocampal volumes in A-allele carriers than GG-homozygotes, and, though statistically weak, also with smaller right caudate volumes in GG-homozygotes than A-allele carriers. Our study results suggest that OTR genotype enhances hippocampal neurogenesis in male GG-homozygotes. Further, prenatal maternal anxiety might induce brain alterations that render GG-homozygotes compared to A-allele carriers more vulnerable to depression.
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Affiliation(s)
- H Acosta
- FinnBrain Birth Cohort Study, Turku Brain and Mind Center, Institute of Clinical Medicine, University of Turku, Turku, Finland; Department of Psychiatry and Psychotherapy, Philipps University of Marburg, Germany.
| | - J J Tuulari
- FinnBrain Birth Cohort Study, Turku Brain and Mind Center, Institute of Clinical Medicine, University of Turku, Turku, Finland; Department of Psychiatry, University of Turku and Turku University Hospital, Turku, Finland; Turku Collegium for Science and Medicine, University of Turku, Finland; Department of Psychiatry, University of Oxford, Oxford, United Kingdom (Sigrid Juselius Fellowship)
| | - K Kantojärvi
- Finnish Institute for Health and Welfare, Genomics and Biobank Unit, Helsinki, Finland; Department of Psychiatry and SleepWell Research Program, Faculty of Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - J D Lewis
- Montreal Neurological Institute, McGill University, Montreal, Canada
| | - N Hashempour
- FinnBrain Birth Cohort Study, Turku Brain and Mind Center, Institute of Clinical Medicine, University of Turku, Turku, Finland
| | - N M Scheinin
- FinnBrain Birth Cohort Study, Turku Brain and Mind Center, Institute of Clinical Medicine, University of Turku, Turku, Finland; Department of Psychiatry, University of Turku and Turku University Hospital, Turku, Finland
| | - S J Lehtola
- FinnBrain Birth Cohort Study, Turku Brain and Mind Center, Institute of Clinical Medicine, University of Turku, Turku, Finland
| | - V S Fonov
- Montreal Neurological Institute, McGill University, Montreal, Canada
| | - D L Collins
- Montreal Neurological Institute, McGill University, Montreal, Canada
| | - A Evans
- Montreal Neurological Institute, McGill University, Montreal, Canada
| | - R Parkkola
- Department of Radiology, University of Turku and Turku University Hospital, Turku, Finland
| | - T Lähdesmäki
- Department of Pediatric Neurology, University of Turku and Turku University Hospital, Turku, Finland
| | - J Saunavaara
- Department of Medical Physics, Turku University Hospital, Turku, Finland
| | - H Merisaari
- FinnBrain Birth Cohort Study, Turku Brain and Mind Center, Institute of Clinical Medicine, University of Turku, Turku, Finland; Department of Future Technologies, University of Turku, Turku, Finland; Center of Computational Imaging and Personalized Diagnostics, Case Western Reserve University, OH, United States
| | - L Karlsson
- FinnBrain Birth Cohort Study, Turku Brain and Mind Center, Institute of Clinical Medicine, University of Turku, Turku, Finland; Centre for Population Health Research, University of Turku and Turku University Hospital, Finland
| | - T Paunio
- Finnish Institute for Health and Welfare, Genomics and Biobank Unit, Helsinki, Finland; Department of Psychiatry and SleepWell Research Program, Faculty of Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - H Karlsson
- FinnBrain Birth Cohort Study, Turku Brain and Mind Center, Institute of Clinical Medicine, University of Turku, Turku, Finland; Department of Psychiatry, University of Turku and Turku University Hospital, Turku, Finland; Centre for Population Health Research, University of Turku and Turku University Hospital, Finland
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18
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Fu D, Huang J, Li K, Chen Y, He Y, Sun Y, Guo Y, Du L, Qu Q, Miao Y, Hu Z. Dihydrotestosterone-induced hair regrowth inhibition by activating androgen receptor in C57BL6 mice simulates androgenetic alopecia. Biomed Pharmacother 2021; 137:111247. [PMID: 33517191 DOI: 10.1016/j.biopha.2021.111247] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/27/2020] [Accepted: 01/03/2021] [Indexed: 12/11/2022] Open
Abstract
Androgenic alopecia (AGA), also known as male pattern baldness, is one of the most common hair loss diseases worldwide. The main treatments of AGA include hair transplant surgery, oral medicines, and LDL laser irradiation, although no treatment to date can fully cure this disease. Animal models play important roles in the exploration of potential mechanisms of disease development and in assessing novel treatments. The present study describes androgen receptor (AR) in C57BL/6 mouse hair follicles that can be activated by dihydrotestosterone (DHT) and translocate to the nucleus. This led to the design of a mouse model of androgen-induced AGA in vivo and in vitro. DHT was found to induce early hair regression, hair miniaturization, hair density loss, and changes in hair morphology in male C57BL/6 mice. These effects of DHT could be partly reversed by the AR antagonist bicalutamide. DHT had similar effects in an ex vivo model of hair loss. Evaluation of histology, organ culture, and protein expression could explain the mechanism by which DHT delayed hair regrowth.
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Affiliation(s)
- Danlan Fu
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China
| | - Junfei Huang
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China
| | - Kaitao Li
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China
| | - Yuxin Chen
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China
| | - Ye He
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China
| | - Yang Sun
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China
| | - Yilong Guo
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China
| | - Lijuan Du
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China
| | - Qian Qu
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China
| | - Yong Miao
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China.
| | - Zhiqi Hu
- Department of Plastic and Aesthetic Surgery Nanfang Hospital of Southern Medical University Guangzhou, Guangdong Province, 510515, China.
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19
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Hoffman JR, Zuckerman A, Ram O, Sadot O, Cohen H. Changes in Hippocampal Androgen Receptor Density and Behavior in Sprague-Dawley Male Rats Exposed to a Low-Pressure Blast Wave. Brain Plast 2020; 5:135-145. [PMID: 33282677 PMCID: PMC7685673 DOI: 10.3233/bpl-200107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Objective The purpose of this study was to examine the effect of exposure of a low-intensity blast wave on androgen receptor (AR) density in the hippocampus and the potential influence on behavioral and cognitive responses. Methods Sprague-Dawley rats were randomly assigned to either a blast exposed group (n = 27) or an unexposed (control) group (n = 10). Animals were treated identically, except that rats within the control group were not exposed to any of the characteristics of the blast wave. Behavior measures were conducted on day seven post-exposure. The rats were initially assessed in the elevated plus maze followed by the acoustic startle response paradigm. Spatial memory performance using the Morris water-maze test was assessed at 8-days post-exposure, for seven consecutive days. Following all behavioral tests AR immunofluorescence staining was performed in different hippocampal subregions. Results A significant elevation in anxiety index (p < 0.001) and impaired learning (p < 0.015) and spatial memory (p < 0.0015) were noted in exposed rats. In addition, a significant attenuation of the AR was noted in the CA1 (p = 0.006) and dentate gyrus (p = 0.031) subregions of the hippocampus in blast exposed animals. Correlational analyses revealed significant associations between AR and both anxiety index (r = -.36, p = 0.031) and memory (r = -0.38, p = 0.019). Conclusions The results of this study demonstrate that exposure to a low-pressure blast wave resulted in a decrease in AR density, which was associated with significant behavioral and cognitive changes.
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Affiliation(s)
- Jay R Hoffman
- Department of Physical Therapy, Ariel University, Ariel, Israel
| | - Amitai Zuckerman
- Anxiety and Stress Research Unit, Beer-Sheva Mental Health Center, Faculty of Health Sciences, Division of Psychiatry, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Omri Ram
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Oren Sadot
- Department of Mechanical Engineering, Ben-Gurion University, Israel
| | - Hagit Cohen
- Anxiety and Stress Research Unit, Beer-Sheva Mental Health Center, Faculty of Health Sciences, Division of Psychiatry, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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20
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Frantsiyants EM, Bandovkina VA, Kaplieva IV, Cheryarina ND, Surikova EI, Neskubina IV, Kotieva IM, Shalashnaya EV, Trepitaki LK. [Influence of malignant growth and chronic neurogenic pain on neurosteroid levels in rat brain]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2020; 66:151-155. [PMID: 32420896 DOI: 10.18097/pbmc20206602151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The aim of the study was to determine the level of sex steroid hormones in white matter of the brain of rats with tumors combined with chronic neurogenic pain (CNP), which was modeled by bilateral sciatic nerve ligation. The study included albino male rats (n=74). In the main group, M1 sarcoma was transplanted subcutaneously (n=11) or into the subclavian vein (n=11) 45 days after CNP modeling. Two comparison groups (n=13 each) included sham operated animals (without CNP) with M1 sarcoma transplanted subcutaneously and intravenously. Control groups included animals with CNP and sham operated animals. Rats were euthanized on day 21 of the carcinogenesis. Levels of total and free testosterone (T), estrone (E1), estradiol (E2), estriol (E3) and progesterone (P4) in the brain white matter were measured using ELISA kits ("Cusabio", China). CNP caused a decrease in the total and free T by 1.5 times (p<0.05), E2 and P4 by 1.9 and 3 times, respectively, E3 by 1.6 times (p<0.05), as well as an increase in E1 by 1.4 times (p<0.05) as compared to the corresponding levels in the brain white matter of rats without CNP. CNP stimulated M1 sarcoma growth in both subcutaneous and intravenous transplantation. Regardless of the tumor site, the dynamics of total T, E2 and E3 in the brain had similar features, but the dynamics of free T, P4 and E1 differed. Thus, changes in the level of neurosteroids in the white matter of rat brain with CNP and tumor growth alone or associated with CNP are a reaction to stress.
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Affiliation(s)
- E M Frantsiyants
- National Medical Research Centre for Oncology, Rostov-on-Don, Russia
| | - V A Bandovkina
- National Medical Research Centre for Oncology, Rostov-on-Don, Russia
| | - I V Kaplieva
- National Medical Research Centre for Oncology, Rostov-on-Don, Russia
| | - N D Cheryarina
- National Medical Research Centre for Oncology, Rostov-on-Don, Russia
| | - E I Surikova
- National Medical Research Centre for Oncology, Rostov-on-Don, Russia
| | - I V Neskubina
- National Medical Research Centre for Oncology, Rostov-on-Don, Russia
| | - I M Kotieva
- National Medical Research Centre for Oncology, Rostov-on-Don, Russia
| | - E V Shalashnaya
- National Medical Research Centre for Oncology, Rostov-on-Don, Russia
| | - L K Trepitaki
- National Medical Research Centre for Oncology, Rostov-on-Don, Russia
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21
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Barch DM, Shirtcliff EA, Elsayed NM, Whalen D, Gilbert K, Vogel AC, Tillman R, Luby JL. Testosterone and hippocampal trajectories mediate relationship of poverty to emotion dysregulation and depression. Proc Natl Acad Sci U S A 2020; 117:22015-22023. [PMID: 32839328 PMCID: PMC7486761 DOI: 10.1073/pnas.2004363117] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
There is robust evidence that early poverty is associated with poor developmental outcomes, including impaired emotion regulation and depression. However, the specific mechanisms that mediate this risk are less clear. Here we test the hypothesis that one pathway involves hormone mechanisms (testosterone and DHEA) that contribute to disruption of hippocampal brain development, which in turn contributes to perturbed emotion regulation and subsequent risk for depression. To do so, we used data from 167 children participating in the Preschool Depression Study, a longitudinal study that followed children from preschool (ages 3 to 5 y) to late adolescence, and which includes prospective assessments of poverty in preschool, measures of testosterone, DHEA, and hippocampal volume across school age and adolescence, and measures of emotion regulation and depression in adolescence. Using multilevel modeling and linear regression, we found that early poverty predicted shallower increases of testosterone, but not DHEA, across development, which in turn predicted shallower trajectories of hippocampal development. Further, we found that early poverty predicted both impaired emotion regulation and depression. The relationship between early poverty and self-reported depression in adolescence was explained by serial mediation through testosterone to hippocampus to emotion dysregulation. There were no significant interactions with sex. These results provide evidence about a hormonal pathway by which early poverty may contribute to disrupted brain development and risk for mental health problems later in life. Identification of such pathways provide evidence for potential points of intervention that might help mitigate the impact of early adversity on brain development.
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Affiliation(s)
- Deanna M Barch
- Department of Psychological & Brain Sciences, Washington University in St. Louis, St. Louis, MO 63130;
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63130
- Department of Radiology, Washington University in St. Louis, St. Louis, MO 63130
| | | | - Nourhan M Elsayed
- Department of Psychological & Brain Sciences, Washington University in St. Louis, St. Louis, MO 63130
| | - Diana Whalen
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63130
| | - Kirsten Gilbert
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63130
| | - Alecia C Vogel
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63130
| | - Rebecca Tillman
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63130
| | - Joan L Luby
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63130
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22
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Jorgensen C, Wang Z. Hormonal Regulation of Mammalian Adult Neurogenesis: A Multifaceted Mechanism. Biomolecules 2020; 10:biom10081151. [PMID: 32781670 PMCID: PMC7465680 DOI: 10.3390/biom10081151] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 07/27/2020] [Accepted: 08/01/2020] [Indexed: 02/07/2023] Open
Abstract
Adult neurogenesis—resulting in adult-generated functioning, integrated neurons—is still one of the most captivating research areas of neuroplasticity. The addition of new neurons in adulthood follows a seemingly consistent multi-step process. These neurogenic stages include proliferation, differentiation, migration, maturation/survival, and integration of new neurons into the existing neuronal network. Most studies assessing the impact of exogenous (e.g., restraint stress) or endogenous (e.g., neurotrophins) factors on adult neurogenesis have focused on proliferation, survival, and neuronal differentiation. This review will discuss the multifaceted impact of hormones on these various stages of adult neurogenesis. Specifically, we will review the evidence for hormonal facilitation (via gonadal hormones), inhibition (via glucocorticoids), and neuroprotection (via recruitment of other neurochemicals such as neurotrophin and neuromodulators) on newly adult-generated neurons in the mammalian brain.
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Affiliation(s)
- Claudia Jorgensen
- Behavioral Science Department, Utah Valley University, Orem, UT 84058, USA
- Correspondence:
| | - Zuoxin Wang
- Psychology Department and Program in Neuroscience, Florida State University, Tallahassee, FL 32306, USA;
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23
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Sex Differences in Maturation and Attrition of Adult Neurogenesis in the Hippocampus. eNeuro 2020; 7:ENEURO.0468-19.2020. [PMID: 32586842 PMCID: PMC7369314 DOI: 10.1523/eneuro.0468-19.2020] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 06/15/2020] [Accepted: 06/18/2020] [Indexed: 12/13/2022] Open
Abstract
Sex differences exist in the regulation of adult neurogenesis in the hippocampus in response to hormones and cognitive training. Here, we investigated the trajectory and maturation rate of adult-born neurons in the dentate gyrus (DG) of male and female rats. Sprague Dawley rats were perfused 2 h, 24 h, one week (1w), 2w, or 3w after bromodeoxyuridine (BrdU) injection, a DNA synthesis marker that labels dividing progenitor cells and their progeny. Adult-born neurons (BrdU/NeuN-ir) matured faster in males compared with females. Males had a greater density of neural stem cells (Sox2-ir) in the dorsal, but not in the ventral, DG and had higher levels of cell proliferation (Ki67-ir) than non-proestrous females. However, males showed a greater reduction in neurogenesis between 1week and 2weeks after mitosis, whereas females showed similar levels of neurogenesis throughout the weeks. The faster maturation and greater attrition of new neurons in males compared with females suggests greater potential for neurogenesis to respond to external stimuli in males and emphasizes the importance of studying sex on adult hippocampal neurogenesis.
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Abstract
17β-Estradiol (E2) is a potent steroid hormone of both gonadal and neuronal origin that exerts profound effects on neuroplasticity in several brain regions. Dendritic spine and synapse formation and rearrangements are modulated and mediated by estrogens. In this chapter, we highlighted the essential background concerning the effects of E2 on synaptic rearrangements accompanied by synaptic plasticity in E2-sensitive brain regions that mediate learning and memory, i.e., cortex and hippocampus. We also address details of the molecular mechanisms underlying E2 regulation of spine dynamics. The proposed models of action of E2 overlaps with that for well-established synaptic modulators, such as adenosine. Thus, the possible synergistic effects of those two molecules in respect to synaptic rearrangement and plasticity were presented.
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Kase Y, Shimazaki T, Okano H. Current understanding of adult neurogenesis in the mammalian brain: how does adult neurogenesis decrease with age? Inflamm Regen 2020; 40:10. [PMID: 32566044 PMCID: PMC7302355 DOI: 10.1186/s41232-020-00122-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 06/08/2020] [Indexed: 02/08/2023] Open
Abstract
Adult neurogenesis occurs throughout life in restricted brain regions in mammals. However, the number of neural stem cells (NSCs) that generate new neurons steadily decreases with age, resulting in a decrease in neurogenesis. Transplantation of mesenchymal cells or cultured NSCs has been studied as a promising treatment in models of several brain injuries including cerebral infarction and cerebral contusion. Considering the problems of host-versus-graft reactions and the tumorigenicity of transplanted cells, the mobilization of endogenous adult NSCs should be more feasible for the treatment of these brain injuries. However, the number of adult NSCs in the adult brain is limited, and their mitotic potential is low. Here, we outline what we know to date about why the number of NSCs and adult neurogenesis decrease with age. We also discuss issues applicable to regenerative medicine.
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Affiliation(s)
- Yoshitaka Kase
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582 Japan.,Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8655 Japan
| | - Takuya Shimazaki
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582 Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582 Japan
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Islam MN, Sakimoto Y, Jahan MR, Ishida M, Tarif AMM, Nozaki K, Masumoto KH, Yanai A, Mitsushima D, Shinoda K. Androgen Affects the Dynamics of Intrinsic Plasticity of Pyramidal Neurons in the CA1 Hippocampal Subfield in Adolescent Male Rats. Neuroscience 2020; 440:15-29. [PMID: 32450298 DOI: 10.1016/j.neuroscience.2020.05.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 05/14/2020] [Accepted: 05/15/2020] [Indexed: 12/18/2022]
Abstract
Androgen receptor (AR) is abundantly expressed in the preoptico-hypothalamic area, bed nucleus of stria terminalis, and medial amygdala of the brain where androgen plays an important role in regulating male sociosexual, emotional and aggressive behaviors. In addition to these brain regions, AR is also highly expressed in the hippocampus, suggesting that the hippocampus is another major target of androgenic modulation. It is known that androgen can modulate synaptic plasticity in the CA1 hippocampal subfield. However, to date, the effects of androgen on the intrinsic plasticity of hippocampal neurons have not been clearly elucidated. In this study, the effects of androgen on the expression of AR in the hippocampus and on the dynamics of intrinsic plasticity of CA1 pyramidal neurons were examined using immunohistochemistry, Western blotting and whole-cell current-clamp recording in unoperated, sham-operated, orchiectomized (OCX), OCX + testosterone (T) or OCX + dihydrotestosterone (DHT)-primed adolescent male rats. Orchiectomy significantly decreased AR-immunoreactivity, resting membrane potential, action potential numbers, afterhyperpolarization amplitude and membrane resistance, whereas it significantly increased action potential threshold and membrane capacitance. These effects were successfully reversed by treatment with either aromatizable androgen T or non-aromatizable androgen DHT. Furthermore, administration of the AR-antagonist flutamide in intact rats showed similar changes to those in OCX rats, suggesting that androgens affect the excitability of CA1 pyramidal neurons possibly by acting on the AR. Our current study potentially clarifies the role of androgen in enhancing the basal excitability of the CA1 pyramidal neurons, which may influence selective neuronal excitation/activation to modulate certain hippocampal functions.
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Affiliation(s)
- Md Nabiul Islam
- Division of Neuroanatomy, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan
| | - Yuya Sakimoto
- Department of Physiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan
| | - Mir Rubayet Jahan
- Division of Neuroanatomy, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan; Department of Anatomy and Histology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Mako Ishida
- Division of Neuroanatomy, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan
| | - Abu Md Mamun Tarif
- Division of Neuroanatomy, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan
| | - Kanako Nozaki
- Division of Neuroanatomy, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan
| | - Koh-Hei Masumoto
- Division of Neuroanatomy, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan
| | - Akie Yanai
- Division of Neuroanatomy, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan; Department of Basic Laboratory Sciences, Faculty of Medicine and Health Sciences, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan
| | - Dai Mitsushima
- Department of Physiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan
| | - Koh Shinoda
- Division of Neuroanatomy, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube 755-8505, Japan.
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Spritzer MD, Roy EA. Testosterone and Adult Neurogenesis. Biomolecules 2020; 10:biom10020225. [PMID: 32028656 PMCID: PMC7072323 DOI: 10.3390/biom10020225] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/22/2020] [Accepted: 01/28/2020] [Indexed: 12/16/2022] Open
Abstract
It is now well established that neurogenesis occurs throughout adulthood in select brain regions, but the functional significance of adult neurogenesis remains unclear. There is considerable evidence that steroid hormones modulate various stages of adult neurogenesis, and this review provides a focused summary of the effects of testosterone on adult neurogenesis. Initial evidence came from field studies with birds and wild rodent populations. Subsequent experiments with laboratory rodents have tested the effects of testosterone and its steroid metabolites upon adult neurogenesis, as well as the functional consequences of induced changes in neurogenesis. These experiments have provided clear evidence that testosterone increases adult neurogenesis within the dentate gyrus region of the hippocampus through an androgen-dependent pathway. Most evidence indicates that androgens selectively enhance the survival of newly generated neurons, while having little effect on cell proliferation. Whether this is a result of androgens acting directly on receptors of new neurons remains unclear, and indirect routes involving brain-derived neurotrophic factor (BDNF) and glucocorticoids may be involved. In vitro experiments suggest that testosterone has broad-ranging neuroprotective effects, which will be briefly reviewed. A better understanding of the effects of testosterone upon adult neurogenesis could shed light on neurological diseases that show sex differences.
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Affiliation(s)
- Mark D. Spritzer
- Department of Biology, Middlebury College, Middlebury, VT 05753, USA
- Correspondence: ; Tel.: 802-443-5676
| | - Ethan A. Roy
- Graduate School of Education, Stanford University, Stanford, CA 94305, USA;
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Prolactin, Estradiol and Testosterone Differentially Impact Human Hippocampal Neurogenesis in an In Vitro Model. Neuroscience 2020; 454:15-39. [PMID: 31930958 PMCID: PMC7839971 DOI: 10.1016/j.neuroscience.2019.12.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 12/11/2019] [Accepted: 12/12/2019] [Indexed: 12/20/2022]
Abstract
Human hippocampal progenitor cells (HPCs) and tissue express classical sex hormone receptors. Prolactin does not impact human HPCs maintained in a proliferative state. Prolactin increases neuronal differentiation of human HPCs only in the short term. Estradiol and testosterone both increase the cell density of proliferating HPCs. Estradiol and testosterone have no observed effect on differentiating HPCs.
Previous studies have indicated that sex hormones such as prolactin, estradiol and testosterone may play a role in the modulation of adult hippocampal neurogenesis (AHN) in rodents and non-human primates, but so far there has been no investigation of their impact on human hippocampal neurogenesis. Here, we quantify the expression levels of the relevant receptors in human post-mortem hippocampal tissue and a human hippocampal progenitor cell (HPC) line. Secondly, we investigate how these hormones modulate hippocampal neurogenesis using a human in vitro cellular model. Human female HPCs were cultured with biologically relevant concentrations of either prolactin, estradiol or testosterone. Bromodeoxyuridine (BrdU) incorporation, immunocytochemistry (ICC) and high-throughput analyses were used to quantify markers determining cell fate after HPCs were either maintained in a proliferative state or allowed to differentiate in the presence of these hormones. In proliferating cells, estrogen and testosterone increased cell density but had no clear effect on markers of proliferation or cell death to account for this. In differentiating cells, a 3-day treatment of prolactin elicited a transient effect, whereby it increased the proportion of microtubule-associated protein 2 (MAP2)-positive and Doublecortin (DCX)-positive cells, but this effect was not apparent after 7-days. At this timepoint we instead observe a decrease in proliferation. Overall, our study demonstrates relatively minor, and possibly short-term effects of sex hormones on hippocampal neurogenesis in human cells. Further work will be needed to understand if our results differ to previous animal research due to species-specific differences, or whether it relates to limitations of our in vitro model.
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