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Mey M, Bhatta S, Suresh S, Labrador LM, Piontkivska H, Casadesus G. Therapeutic benefits of central LH receptor agonism in the APP/PS1 AD model involve trophic and immune regulation and are reproductive status dependent. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167165. [PMID: 38653355 DOI: 10.1016/j.bbadis.2024.167165] [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: 02/06/2024] [Revised: 04/02/2024] [Accepted: 04/08/2024] [Indexed: 04/25/2024]
Abstract
The mechanisms that underly reproductive hormone effects on cognition, neuronal plasticity, and AD risk, particularly in relation to gonadotropin LH receptor (LHCGR) signaling, remain poorly understood. To address this gap in knowledge and clarify the impact of circulating steroid hormones on the therapeutic effects of CNS LHCGR activation, we delivered the LHCGR agonist human chorionic gonadotropin (hCG) intracerebroventricularly (ICV) and evaluated functional, structural, plasticity-related signaling cascades, Aβ pathology, and transcriptome differences in reproductively intact and ovariectomized (OVX) APP/PS1 AD female mice. Here we demonstrate that CNS hCG delivery restored function to wild-type levels only in OVX APP/PS1 mice. Spine density was increased in all hCG treated groups independently of reproductive status. Notably, increases in BDNF signaling and cognition, were selectively upregulated only in the OVX hCG-treated group. RNA sequencing analyses identified a significant increase in peripheral myeloid and pro-inflammatory genes within the hippocampi of the OVX group that were completely reversed by hCG treatment, identifying a potential mechanism underlying the selective therapeutic effect of LHCGR activation. Interestingly, in intact mice, hCG administration mimicked the effects of gonadectomy. Together, our findings indicate that CNS LHCGR agonism in the post-menopausal context is beneficial through trophic and immune mechanisms. Our findings also underscore the presence of a steroid-LHCGR mechanistic interaction that is unexplored yet potentially meaningful to fully understand "post-menopausal" brain function and CNS hormone treatment response.
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Affiliation(s)
- Megan Mey
- Kent State University, Kent, OH 44240, United States of America
| | - Sabina Bhatta
- Case Western Reserve University, Cleveland, OH 44106, United States of America
| | - Sneha Suresh
- University of Florida, Gainesville, FL 32606, United States of America
| | | | | | - Gemma Casadesus
- University of Florida, Gainesville, FL 32606, United States of America.
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2
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Mey M, Bhatta S, Suresh S, Montero Labrador L, Piontkivska H, Casadesus G. The LH receptor regulates hippocampal spatial memory and restores dendritic spine density in ovariectomized APP/PS1 AD mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573087. [PMID: 38187770 PMCID: PMC10769359 DOI: 10.1101/2023.12.22.573087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Activation of the luteinizing hormone receptor (LHCGR) rescues spatial memory function and spine density losses associated with gonadectomy and high circulating gonadotropin levels in females. However, whether this extends to the AD brain or the mechanisms that underlie these benefits remain unknown. To address this question, we delivered the LHCGR agonist human chorionic gonadotropin (hCG) intracerebroventricularly (ICV), under reproductively intact and ovariectomized conditions to mimic the post-menopausal state in the APP/PS1mouse brain. Cognitive function was tested using the Morris water maze task, and hippocampal dendritic spine density, Aβ pathology, and signaling changes associated with these endpoints were determined to address mechanisms. Here we show that central LHCGR activation restored function in ovariectomized APP/PS1 female mice to wild-type levels without altering Aβ pathology. LHCGR activation increased hippocampal dendritic spine density regardless of reproductive status, and this was mediated by BDNF-dependent and independent signaling. We also show that ovariectomy in the APP/PS1 brain elicits an increase in peripherally derived pro-inflammatory genes which are inhibited by LHCGR activation. This may mediate reproductive status specific effects of LHCGR agonism on cognitive function and BDNF expression. Together, this work highlights the relevance of the LHCGR on cognition and its therapeutic potential in the "menopausal" AD brain.
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3
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Sims S, Barak O, Ryu V, Miyashita S, Kannangara H, Korkmaz F, Wizman S, Macdonald A, Gumerova A, Goosens K, Zaidi M, Yuen T, Lizneva D, Frolinger T. Absent LH signaling rescues the anxiety phenotype in aging female mice. Mol Psychiatry 2023; 28:3324-3331. [PMID: 37563278 DOI: 10.1038/s41380-023-02209-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 07/25/2023] [Accepted: 07/27/2023] [Indexed: 08/12/2023]
Abstract
Clinical studies and experimental data together support a role for pituitary gonadotropins, including luteinizing hormone (LH), otherwise considered solely as fertility hormones, in age-related cognitive decline. Furthermore, rising levels of LH in post-menopausal women have been implicated in the high prevalence of mood disorders. This study was designed to examine the effect of deficient LH signaling on both cognitive and emotional behavior in 12-month-old Lhcgr-/- mice. For this, we established and validated a battery of five tests, including Dark-Light Box (DLB), Y-Maze Spontaneous Alternation, Novel Object Recognition (NOR), and contextual and cued Fear Conditioning (FCT) tests. We found that 12-month-old female wild type mice display a prominent anxiety phenotype on DLB and FCT. This phenotype was not seen in 12-month-old female Lhcgr-/- mice, indicating full phenotypic rescue. Furthermore, there was no effect of LHCGR depletion on recognition memory or working spatial memory on NOR and Y-maze testing, respectively, in 12-month-old mice, notwithstanding the absence of a basal phenotype in wild type littermates. The latter data do not exclude an effect of LH on cognition documented in previous studies. Finally, 12-month-old male mice and 3-month-old male and female mice did not consistently display deficits on any test. The data collectively document, for the first time, that loss of LH signaling reverses age-related emotional disturbances, a prelude to future targeted therapies that block LH action.
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Affiliation(s)
- Steven Sims
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Orly Barak
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Vitaly Ryu
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Sari Miyashita
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Hasni Kannangara
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Funda Korkmaz
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Soleil Wizman
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Anne Macdonald
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Anisa Gumerova
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Ki Goosens
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Mone Zaidi
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Tony Yuen
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Daria Lizneva
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Tal Frolinger
- Center for Translational Medicine and Pharmacology, Departments of Pharmacological Sciences and of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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4
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Ryu V, Gumerova A, Korkmaz F, Kang SS, Katsel P, Miyashita S, Kannangara H, Cullen L, Chan P, Kuo T, Padilla A, Sultana F, Wizman SA, Kramskiy N, Zaidi S, Kim SM, New MI, Rosen CJ, Goosens KA, Frolinger T, Haroutunian V, Ye K, Lizneva D, Davies TF, Yuen T, Zaidi M. Brain atlas for glycoprotein hormone receptors at single-transcript level. eLife 2022; 11:e79612. [PMID: 36052994 PMCID: PMC9473692 DOI: 10.7554/elife.79612] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 09/02/2022] [Indexed: 11/24/2022] Open
Abstract
There is increasing evidence that anterior pituitary hormones, traditionally thought to have unitary functions in regulating single endocrine targets, act on multiple somatic tissues, such as bone, fat, and liver. There is also emerging evidence for anterior pituitary hormone action on brain receptors in mediating central neural and peripheral somatic functions. Here, we have created the most comprehensive neuroanatomical atlas on the expression of TSHR, LHCGR, and FSHR. We have used RNAscope, a technology that allows the detection of mRNA at single-transcript level, together with protein level validation, to document Tshr expression in 173 and Fshr expression in 353 brain regions, nuclei and subnuclei identified using the Atlas for the Mouse Brain in Stereotaxic Coordinates. We also identified Lhcgr transcripts in 401 brain regions, nuclei and subnuclei. Complementarily, we used ViewRNA, another single-transcript detection technology, to establish the expression of FSHR in human brain samples, where transcripts were co-localized in MALAT1-positive neurons. In addition, we show high expression for all three receptors in the ventricular region-with yet unknown functions. Intriguingly, Tshr and Fshr expression in the ependymal layer of the third ventricle was similar to that of the thyroid follicular cells and testicular Sertoli cells, respectively. In contrast, Fshr was localized to NeuN-positive neurons in the granular layer of the dentate gyrus in murine and human brain-both are Alzheimer's disease-vulnerable regions. Our atlas thus provides a vital resource for scientists to explore the link between the stimulation or inactivation of brain glycoprotein hormone receptors on somatic function. New actionable pathways for human disease may be unmasked through further studies.
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Affiliation(s)
- Vitaly Ryu
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Anisa Gumerova
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Funda Korkmaz
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Seong Su Kang
- Department of Pathology, Emory University School of MedicineAtlantaUnited States
| | - Pavel Katsel
- Department of Psychiatry, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Sari Miyashita
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Hasni Kannangara
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Liam Cullen
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | | | - TanChun Kuo
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Ashley Padilla
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Farhath Sultana
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Soleil A Wizman
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Natan Kramskiy
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Samir Zaidi
- Memorial Sloan Kettering Cancer CenterNew YorkUnited States
| | - Se-Min Kim
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Maria I New
- Department of Pediatrics, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | | | - Ki A Goosens
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Psychiatry, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Tal Frolinger
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Vahram Haroutunian
- Department of Psychiatry, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Keqiang Ye
- Faculty of Life and Health Sciences, and Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced technology, Chinese Academy of SciencesShenzhenChina
| | - Daria Lizneva
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Terry F Davies
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Tony Yuen
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
| | - Mone Zaidi
- Center for Translational Medicine and Pharmacology, Icahn School of Medicine at Mount SinaiNew YorkUnited States
- Department of Medicine and of Pharmacological Sciences, Icahn School of Medicine at Mount SinaiNew YorkUnited States
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5
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Butler T, Goldberg JD, Galvin JE, Maloney T, Ravdin L, Glodzik L, de Leon MJ, Hochman T, Bowen RL, Atwood CS. Rationale, study design and implementation of the LUCINDA Trial: Leuprolide plus Cholinesterase Inhibition to reduce Neurologic Decline in Alzheimer's. Contemp Clin Trials 2021; 107:106488. [PMID: 34166841 PMCID: PMC8550816 DOI: 10.1016/j.cct.2021.106488] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 11/20/2022]
Abstract
The LUCINDA Trial (Leuprolide plus Cholinesterase Inhibition to reduce Neurologic Decline in Alzheimer's) is a 52 week, randomized, placebo-controlled trial of leuprolide acetate (Eligard) in women with Alzheimer's disease (AD). Leuprolide acetate is a gonadotropin analogue commonly used for hormone-sensitive conditions such as prostate cancer and endometriosis. This repurposed drug demonstrated efficacy in a previous Phase II clinical trial in those women with AD who also received a stable dose of the acetylcholinesterase inhibitor donepezil (Bowen et al., 2015). Basic biological, epidemiological and clinical trial data suggest leuprolide acetate mediates improvement and stabilization of neuropathology and cognitive performance via the modulation of gonadotropin and/or gonadotropin-releasing hormone signaling. LUCINDA will enroll 150 women with mild-moderate AD who are receiving a stable dose of donepezil from three study sites in the United States. Cognition and function are the primary outcome measures as assessed by the Alzheimer's Disease Assessment Scale-Cognitive Subscale. Blood and MRI biomarkers are also measured to assess hormonal, inflammatory and AD biomarker changes. We present the protocol for LUCINDA and discuss trial innovations and challenges including changes necessitated by the covid-19 pandemic and study drug procurement issues.
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Affiliation(s)
- Tracy Butler
- Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, NY 10021, USA.
| | - Judith D Goldberg
- Departments of Population Health and Environmental Medicine, New York University School of Medicine, New York, NY 10016, USA
| | - James E Galvin
- Comprehensive Center for Brain Health, Departments of Neurology and Psychiatry, University of Miami, Miller School of Medicine, Boca Raton, FL 33433, USA
| | - Thomas Maloney
- Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, NY 10021, USA
| | - Lisa Ravdin
- Department of Neurology, Weill Cornell Medicine, New York, NY 10021, USA
| | - Lidia Glodzik
- Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, NY 10021, USA
| | - Mony J de Leon
- Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, NY 10021, USA
| | - Tsivia Hochman
- Departments of Population Health and Environmental Medicine, New York University School of Medicine, New York, NY 10016, USA
| | | | - Craig S Atwood
- Division of Geriatrics and Gerontology, Department of Medicine, University of Wisconsin School of Medicine and Public Health, and Geriatric Research, Education and Clinical Center, Veterans Administration Hospital, Madison, WI 53705, USA
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6
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Mey M, Bhatta S, Casadesus G. Luteinizing hormone and the aging brain. VITAMINS AND HORMONES 2021; 115:89-104. [PMID: 33706966 PMCID: PMC9853463 DOI: 10.1016/bs.vh.2020.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Fluctuations in luteinizing hormone (LH) release contribute to the development and maintenance of the reproductive system and become dysregulated during aging. Of note, increasing evidence supports extra-gonadal roles for LH within the CNS, particularly as it relates to cognition and plasticity in aging and age-related degenerative diseases such as Alzheimer's disease (AD). However, despite increasing evidence that supports a link between this hormone and CNS function, the mechanisms underlying LH action within the brain and how they influence cognition and plasticity during the lifespan is poorly understood and, in fact, often in conflict. This chapter aims to provide an up-to-date review of the literature addressing the role of LH signaling in the context of CNS aging and disease and put forward a unifying hypothesis that may explain currently conflicting theories regarding the role of LHCGR signaling in CNS function and dysfunction in aging and disease.
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Affiliation(s)
- Megan Mey
- Department of Biomedical Science, Kent State University, Cunningham Hall, Kent, OH, United States
| | - Sabina Bhatta
- Department of Biomedical Science, Kent State University, Cunningham Hall, Kent, OH, United States
| | - Gemma Casadesus
- Department of Biological Science, School of Arts and Sciences, Kent State University, Cunningham Hall, Kent, OH, United States,Corresponding author: ;
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7
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Diabetic encephalopathy causes the imbalance of neural activities between hippocampal glutamatergic neurons and GABAergic neurons in mice. Brain Res 2020; 1742:146863. [PMID: 32360099 DOI: 10.1016/j.brainres.2020.146863] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/23/2020] [Accepted: 04/26/2020] [Indexed: 12/13/2022]
Abstract
Diabetic encephalopathy is a severe diabetes-related complication in the central nervous system (CNS) that is characterized by the impairment of neurochemical and structural changes leading to cognitive dysfunction. Its cellular and molecular mechanisms are still unclear and clinical approaches are still lacking of promising therapies. In this study, we have investigated the changes of different hippocampal neurons during diabetic encephalopathy in mouse models of diabetes by simultaneously analyzing the activities and synaptic transmission of glutamatergic neurons and GABAergic neurons in brain slices. Compared with the data from a group of control, diabetic encephalopathy permanently impairs the excitability of GABAergic neurons and synaptic transmission mediated by γ-aminobutyric acid (GABA). However, glutamatergic neurons appear to be more excited. Our findings highlight the critical role of the dysfunction of GABAergic neurons and glutamatergic neurons during diabetic encephalopathy in hippocampus to neural impairment as well as a strategy to prevent the function of progress of diabetic encephalopathy by protecting central neurons.
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8
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Deems NP, Leuner B. Pregnancy, postpartum and parity: Resilience and vulnerability in brain health and disease. Front Neuroendocrinol 2020; 57:100820. [PMID: 31987814 PMCID: PMC7225072 DOI: 10.1016/j.yfrne.2020.100820] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 11/25/2019] [Accepted: 01/21/2020] [Indexed: 02/07/2023]
Abstract
Risk and resilience in brain health and disease can be influenced by a variety of factors. While there is a growing appreciation to consider sex as one of these factors, far less attention has been paid to sex-specific variables that may differentially impact females such as pregnancy and reproductive history. In this review, we focus on nervous system disorders which show a female bias and for which there is data from basic research and clinical studies pointing to modification in disease risk and progression during pregnancy, postpartum and/or as a result of parity: multiple sclerosis (MS), depression, stroke, and Alzheimer's disease (AD). In doing so, we join others (Shors, 2016; Galea et al., 2018a) in aiming to illustrate the importance of looking beyond sex in neuroscience research.
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Affiliation(s)
- Nicholas P Deems
- The Ohio State University, Department of Psychology, Columbus, OH, USA
| | - Benedetta Leuner
- The Ohio State University, Department of Psychology, Columbus, OH, USA.
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9
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Mariani MM, Mojziszek K, Curley E, Thornton JE. Lowering luteinizing hormone (LH) reverses spatial memory deficits associated with neurotoxin infusion into the hippocampus of ovx rats. Horm Behav 2020; 119:104631. [PMID: 31759942 DOI: 10.1016/j.yhbeh.2019.104631] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 10/24/2019] [Accepted: 10/28/2019] [Indexed: 01/14/2023]
Affiliation(s)
- Monica M Mariani
- Neuroscience Department, Oberlin College, 119 Woodland Street, Oberlin, OH 44074, USA.
| | - Kirsten Mojziszek
- Neuroscience Department, Oberlin College, 119 Woodland Street, Oberlin, OH 44074, USA
| | - Emily Curley
- Neuroscience Department, Oberlin College, 119 Woodland Street, Oberlin, OH 44074, USA
| | - Janice E Thornton
- Neuroscience Department, Oberlin College, 119 Woodland Street, Oberlin, OH 44074, USA
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10
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Jahanshahi M, Saeidi M, Nikmahzar E, Babakordi F, Bahlakeh G. Effects of hCG on reduced numbers of hCG receptors in the prefrontal cortex and cerebellum of rat models of Alzheimer's disease. Biotech Histochem 2019; 94:360-365. [PMID: 30760053 DOI: 10.1080/10520295.2019.1571228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Age-associated changes in the levels of luteinizing hormone and human chorionic gonadotropin (hCG) are potential risk factors for Alzheimer's disease (AD); hCG concentration is related to the incidence of AD. The highest density of hCG receptors is in zones of the brain that are vulnerable to AD and streptozotocin (STZ) can decrease the density of this receptor. We investigated the effects of different doses of hCG on hCG receptor density in the prefrontal cortex and cerebellum in a rat model of STZ-induced AD. AD was induced by intracerebroventricular injection of 3 mg/kg STZ. The resulting AD rats were treated for 3 days with 50, 100 or 200 IU/200 μl hCG, or with saline as a control. Sections of prefrontal cortex and cerebellum were stained immunohistochemically and hCG receptor-immunoreactive (ir) neurons were counted. STZ injected into the lateral ventricles of rat brains reduced the density of hCG receptor-ir neurons in the prefrontal cortex and cerebellum. hCG administration resulted in a significant dose-dependent increase in the number of hCG receptor-ir neurons in the prefrontal cortex and cerebellum. The maximum increase in the number of receptors occurred following the 200 IU dose of hCG. Administration of hCG ameliorated the lowered density of hCG receptor-ir neurons in the cerebellum and prefrontal cortex in STZ-induced AD rats.
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Affiliation(s)
- M Jahanshahi
- a Neuroscience Research Center, Golestan University of Medical Sciences , Gorgan , Iran
| | - M Saeidi
- b Stem Cell Research Center, Golestan University of Medical Sciences , Gorgan , Iran
| | - E Nikmahzar
- a Neuroscience Research Center, Golestan University of Medical Sciences , Gorgan , Iran
| | - F Babakordi
- a Neuroscience Research Center, Golestan University of Medical Sciences , Gorgan , Iran
| | - G Bahlakeh
- a Neuroscience Research Center, Golestan University of Medical Sciences , Gorgan , Iran
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11
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Blair JA, Bhatta S, Casadesus G. CNS luteinizing hormone receptor activation rescues ovariectomy-related loss of spatial memory and neuronal plasticity. Neurobiol Aging 2019; 78:111-120. [PMID: 30925299 DOI: 10.1016/j.neurobiolaging.2019.02.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 01/31/2019] [Accepted: 02/01/2019] [Indexed: 10/27/2022]
Abstract
Ovariectomy (OVX), a menopause model, leads to cognition and neuronal plasticity deficits that are rescued by estrogen administration or downregulation of pituitary luteinizing hormone (LH). LH is present in the brain. However, whether LH levels differ across brain regions, change across reproductive stages, or whether brain-specific LHR signaling play a role in OVX-related cognitive and neuroplasticity losses is completely unknown. To address this, we measured brain LH in cycling and OVX C57Bl/6 across brain regions and determined whether OVX-related functional and plasticity deficits could be rescued by intracerebroventricular administration of the LHR agonist (hCG). Here, we show that while pituitary LH is increased in OVX, brain LH is decreased, primarily in spatial memory and navigation areas. Furthermore, intracerebroventricular hCG delivery after OVX rescued dendritic spine density and spatial memory. In vitro, we show that hCG increased neurite outgrowth in primary hippocampal neurons in a receptor-specific manner. Taken together, our data suggest that loss of brain LH signaling is involved in cognitive and plasticity losses associated with OVX and loss of ovarian hormones.
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Affiliation(s)
- Jeffrey A Blair
- Department of Biological Sciences, Kent State University, Kent, OH, USA
| | - Sabina Bhatta
- Department of Biological Sciences, Kent State University, Kent, OH, USA
| | - Gemma Casadesus
- Department of Biological Sciences, Kent State University, Kent, OH, USA.
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12
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Bhatta S, Blair JA, Casadesus G. Luteinizing Hormone Involvement in Aging Female Cognition: Not All Is Estrogen Loss. Front Endocrinol (Lausanne) 2018; 9:544. [PMID: 30319538 PMCID: PMC6165885 DOI: 10.3389/fendo.2018.00544] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 08/28/2018] [Indexed: 01/29/2023] Open
Abstract
Pervasive age-related dysfunction in hypothalamic-pituitary-gonadal (HPG) axis is associated with cognitive impairments in aging as well as pathogenesis of age-related neurodegenerative diseases such as the Alzheimer's disease (AD). As a major regulator of the HPG axis, the steroid hormone estrogen has been widely studied for its role in regulation of memory. Although estrogen modulates both cognition as well as cognition associated morphological components in a healthy state, the benefits of estrogen replacement therapy on cognition and disease seem to diminish with advancing age. Emerging data suggests an important role for luteinizing hormone (LH) in CNS function, which is another component of the HPG axis that becomes dysregulated during aging, particularly in menopause. The goal of this review is to highlight the current existing literature on LH and provide new insights on possible mechanisms of its action.
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Affiliation(s)
- Sabina Bhatta
- School of Biomedical Sciences, Kent State University, Kent, OH, United States
| | - Jeffrey A. Blair
- School of Biomedical Sciences, Kent State University, Kent, OH, United States
| | - Gemma Casadesus
- School of Biomedical Sciences, Kent State University, Kent, OH, United States
- Department of Biological Sciences, Kent State University, Kent, OH, United States
- *Correspondence: Gemma Casadesus
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Burnham V, Sundby C, Laman-Maharg A, Thornton J. Luteinizing hormone acts at the hippocampus to dampen spatial memory. Horm Behav 2017; 89:55-63. [PMID: 27847314 DOI: 10.1016/j.yhbeh.2016.11.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 11/07/2016] [Accepted: 11/09/2016] [Indexed: 01/06/2023]
Abstract
Luteinizing hormone (LH) rises dramatically during and after menopause, and has been correlated with an increased incidence of Alzheimer's disease and decreased memory performance in humans and animal models. To test whether LH acts directly on the dorsal hippocampus to affect memory, ovariectomized female rats were infused with either the LH-homologue human chorionic gonadotropin (hCG) or the LH receptor antagonist deglycosylated-hCG (dg-hCG). Infusion of hCG into either the lateral ventricle or the dorsal hippocampus caused significant memory impairments in ovariectomized estradiol-treated females. Consistent with this, infusion of the LH antagonist dg-hCG into the dorsal hippocampus caused an amelioration of memory deficits in ovariectomized females. Furthermore, the gonadotropin-releasing hormone antagonist Antide, failed to act in the hippocampus to affect memory. These findings demonstrate a significant role for LH action in the dorsal hippocampus in spatial memory dysfunction.
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Affiliation(s)
- Veronica Burnham
- Department of Neuroscience, Oberlin College, 119 Woodland St, Oberlin, OH 44074, USA
| | - Christopher Sundby
- Department of Neuroscience, Oberlin College, 119 Woodland St, Oberlin, OH 44074, USA
| | - Abigail Laman-Maharg
- Department of Neuroscience, Oberlin College, 119 Woodland St, Oberlin, OH 44074, USA
| | - Janice Thornton
- Department of Neuroscience, Oberlin College, 119 Woodland St, Oberlin, OH 44074, USA.
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Abstract
Alzheimer disease (AD) is a slow progressive neurodegenerative disease that affects more elderly women than elderly men. It impairs memory, typically progresses into multidomain cognitive decline that destroys the quality of life, and ultimately leads to death. About 5.3 million older Americans are now living with this disease, and this number is projected to rise to 14 million by 2050. Annual health-care costs in the United States alone are projected to increase to about US$1.1 trillion by 2050. The initial theory that decreasing estrogen levels leads to AD development in postmenopausal women has been proven inconclusive. For example, Women's Health Research Initiative Memory Study and the population-based nested case-control study have failed to demonstrate that estrogen/progesterone (hormone replacement therapy [HRT]) or estrogen replacement therapy could prevent the cognitive decline or reduce the risk of AD. This led to the realization that AD development could be due to a progressive increase in luteinizing hormone (LH) levels in postmenopausal women. Accordingly, a large number of studies have demonstrated that an increase in LH levels is positively correlated with neuropathological, behavioral, and cognitive changes in AD. In addition, LH has been shown to promote amyloidogenic pathway of precursor protein metabolism and deposition of amyloid β plaques in the hippocampus, a region involved in AD. Cognate receptors that mediate LH effects are abundantly expressed in the hippocampus. Reducing the LH levels by treatment with gonadotropin-releasing hormone agonists could provide therapeutic benefits. Despite these advances, many questions remain and require further research.
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Affiliation(s)
- C V Rao
- 1 Department of Cellular Biology and Pharmacology, Reproduction and Development Program, Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA.,2 Department of Molecular and Human Genetics, Reproduction and Development Program, Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA.,3 Department of Obstetrics and Gynecology, Reproduction and Development Program, Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA
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15
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Blair JA, Palm R, Chang J, McGee H, Zhu X, Wang X, Casadesus G. Luteinizing hormone downregulation but not estrogen replacement improves ovariectomy-associated cognition and spine density loss independently of treatment onset timing. Horm Behav 2016; 78:60-6. [PMID: 26497249 PMCID: PMC4718885 DOI: 10.1016/j.yhbeh.2015.10.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 10/12/2015] [Accepted: 10/20/2015] [Indexed: 12/31/2022]
Abstract
Age-related changes in reproductive hormone levels are a well-known risk factor for the development of cognitive dysfunction and dementia in women. We and others have shown an important contribution of gonadotropins in this process. Lowering serum gonadotropin levels is able to rescue cognitive function in Alzheimer's disease and menopause models, but whether this is time-dependent and the exact mechanism through which gonadotropins regulate cognitive function is unknown. We show that pharmacologically lowering serum levels of luteinizing hormone lead to cognitive improvement immediately after ovariectomy and with a 4month interval after ovariectomy, when the benefits of 17β-estradiol are known to disappear in rodents. Importantly, we show that these improvements are associated with spine density changes at both time points. These findings suggest a role of luteinizing hormone in learning and memory and neuroplasticity processes as well as provide an alternative therapeutic strategy of menopause associated cognitive loss.
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Affiliation(s)
- Jeffrey A Blair
- School of Biomedical Sciences, Kent State University, Kent, OH, United States; Department of Biological Sciences, Kent State University, Kent, OH, United States
| | - Russell Palm
- College of Medicine and Life Sciences, University of Toledo, Toledo, OH, United States
| | - Jaewon Chang
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
| | - Henry McGee
- Department of Biological Sciences, Kent State University, Kent, OH, United States
| | - Xiongwei Zhu
- Department of Pathology, Case Western Reserve University, Cleveland, OH, United States
| | - Xinglong Wang
- Department of Pathology, Case Western Reserve University, Cleveland, OH, United States
| | - Gemma Casadesus
- Department of Biological Sciences, Kent State University, Kent, OH, United States.
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Blair JA, Bhatta S, McGee H, Casadesus G. Luteinizing hormone: Evidence for direct action in the CNS. Horm Behav 2015; 76:57-62. [PMID: 26172857 PMCID: PMC4741372 DOI: 10.1016/j.yhbeh.2015.06.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 07/06/2015] [Accepted: 07/07/2015] [Indexed: 01/09/2023]
Abstract
This article is part of a Special Issue "SBN 2014". Hormonal dysfunction due to aging, especially during menopause, plays a substantial role in cognitive decline as well as the progression and development of neurodegenerative diseases. The hypothalamic-pituitary-gonadal (HPG) axis has long been implicated in changes in behavior and neuronal morphology. Most notably, estrogens have proven beneficial in the healthy brain through a host of different mechanisms. Recently, luteinizing hormone (LH) has emerged as a candidate for further investigation for its role in the CNS. The basis of this is that both LH and the LH receptor are expressed in the brain, and serum levels of LH correlate with cognitive deficits and Alzheimer's disease (AD) incidence. The study of LH in cognition and AD primarily focuses on evaluating the effects of downregulation of this peptide. This literature has shown that decreasing peripheral LH, through a variety of pharmacological interventions, reduces cognitive deficits in ovariectomy and AD models. However, few studies have researched the direct actions of LH on neurons and glial cells. Here we summarize the role of luteinizing hormone in modulating cognition, and we propose a mechanism that underlies a role for brain LH in this process.
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Affiliation(s)
- Jeffrey A Blair
- School of Biomedical Sciences, Kent State University, Kent, OH, USA
| | - Sabina Bhatta
- School of Biomedical Sciences, Kent State University, Kent, OH, USA
| | - Henry McGee
- Department of Biological Sciences, Kent State University, Kent, OH, USA
| | - Gemma Casadesus
- Department of Biological Sciences, Kent State University, Kent, OH, USA.
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Atwood CS, Bowen RL. The endocrine dyscrasia that accompanies menopause and andropause induces aberrant cell cycle signaling that triggers re-entry of post-mitotic neurons into the cell cycle, neurodysfunction, neurodegeneration and cognitive disease. Horm Behav 2015; 76:63-80. [PMID: 26188949 PMCID: PMC4807861 DOI: 10.1016/j.yhbeh.2015.06.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 06/23/2015] [Accepted: 06/23/2015] [Indexed: 12/26/2022]
Abstract
This article is part of a Special Issue "SBN 2014". Sex hormones are physiological factors that promote neurogenesis during embryonic and fetal development. During childhood and adulthood these hormones support the maintenance of brain structure and function via neurogenesis and the formation of dendritic spines, axons and synapses required for the capture, processing and retrieval of information (memories). Not surprisingly, changes in these reproductive hormones that occur with menopause and during andropause are strongly correlated with neurodegeneration and cognitive decline. In this connection, much evidence now indicates that Alzheimer's disease (AD) involves aberrant re-entry of post-mitotic neurons into the cell cycle. Cell cycle abnormalities appear very early in the disease, prior to the appearance of plaques and tangles, and explain the biochemical, neuropathological and cognitive changes observed with disease progression. Intriguingly, a recent animal study has demonstrated that induction of adult neurogenesis results in the loss of previously encoded memories while decreasing neurogenesis after memory formation during infancy mitigated forgetting. Here we review the biochemical, epidemiological and clinical evidence that alterations in sex hormone signaling associated with menopause and andropause drive the aberrant re-entry of post-mitotic neurons into an abortive cell cycle that leads to neurite retraction, neuron dysfunction and neuron death. When the reproductive axis is in balance, gonadotropins such as luteinizing hormone (LH), and its fetal homolog, human chorionic gonadotropin (hCG), promote pluripotent human and totipotent murine embryonic stem cell and neuron proliferation. However, strong evidence supports menopausal/andropausal elevations in the LH:sex steroid ratio as driving aberrant mitotic events. These include the upregulation of tumor necrosis factor; amyloid-β precursor protein processing towards the production of mitogenic Aβ; and the activation of Cdk5, a key regulator of cell cycle progression and tau phosphorylation (a cardinal feature of both neurogenesis and neurodegeneration). Cognitive and biochemical studies confirm the negative consequences of a high LH:sex steroid ratio on dendritic spine density and human cognitive performance. Prospective epidemiological and clinical evidence in humans supports the premise that rebalancing the ratio of circulating gonadotropins:sex steroids reduces the incidence of AD. Together, these data support endocrine dyscrasia and the subsequent loss of cell cycle control as an important etiological event in the development of neurodegenerative diseases including AD, stroke and Parkinson's disease.
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Affiliation(s)
- Craig S Atwood
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53705, USA; Geriatric Research, Education and Clinical Center, Veterans Administration Hospital, Madison, WI 53705, USA; School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Joondalup, 6027 WA, Australia.
| | - Richard L Bowen
- OTB Research, 217 Calhoun St, Unit 1, Charleston, SC 29401, USA
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Burnham VL, Thornton JE. Luteinizing hormone as a key player in the cognitive decline of Alzheimer's disease. Horm Behav 2015; 76:48-56. [PMID: 26031357 DOI: 10.1016/j.yhbeh.2015.05.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 05/10/2015] [Accepted: 05/25/2015] [Indexed: 12/30/2022]
Abstract
This article is part of a Special Issue "SBN 2014". Alzheimer's disease is one of the most prevalent and costly neurological diseases in the world. Although decades of research have focused on understanding Alzheimer's disease pathology and progression, there is still a great lack of clinical treatments for those who suffer from it. One of the factors most commonly associated with the onset of Alzheimer's disease is a decrease in levels of gonadal hormones, such as estrogens and androgens. Despite the correlational and experimental data which support the role of these hormones in the etiology of Alzheimer's disease, clinical trials involving their reintroduction through hormone therapy have had varied results and these gonadal hormones often have accompanying health risks. More recently, investigation has turned toward other hormones in the hypothalamic-pituitary-gonadal axis that are disrupted by age-related decreases in gonadal hormones. Specifically, luteinizing hormone, which is increased with age in both men and women (in response to removal of negative feedback), has surfaced as a potentially powerful player in the risk and onset of Alzheimer's disease. Mounting evidence in basic research and epidemiological studies supports the role of elevated luteinizing hormone in exacerbating age-related cognitive decline in both males and females. This review summarizes the recent developments involving luteinizing hormone in increasing the cognitive deficits and molecular pathology characteristic of Alzheimer's disease.
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Affiliation(s)
- Veronica L Burnham
- Department of Neuroscience, Oberlin College, 119 Woodland St, Oberlin, OH 44074, USA
| | - Janice E Thornton
- Department of Neuroscience, Oberlin College, 119 Woodland St, Oberlin, OH 44074, USA.
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Verdile G, Asih PR, Barron AM, Wahjoepramono EJ, Ittner LM, Martins RN. The impact of luteinizing hormone and testosterone on beta amyloid (Aβ) accumulation: Animal and human clinical studies. Horm Behav 2015; 76:81-90. [PMID: 26122291 DOI: 10.1016/j.yhbeh.2015.05.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 05/20/2015] [Accepted: 05/25/2015] [Indexed: 12/31/2022]
Abstract
This article is part of a Special Issue "SBN 2014". Hormonal changes associated with ageing have been implicated in the pathogenesis of Alzheimer's disease (AD), the most common form of dementia. Reductions in serum testosterone and increases in luteinizing hormone (LH) are established AD risk factors for dementia in men and have important roles in modulating AD pathogenesis. One of the defining features of AD is the accumulation of amyloid-beta (Aβ) in the brain, which has a key role in the neurodegenerative cascade. Both testosterone and LH have been shown to modulate CNS Aβ accumulation in animal studies, and associations with cerebral amyloid load in human studies have supported this. The underlying mechanisms by which these hormones modulate Aβ accumulation and contribute to neurodegeneration are not completely understood, however they have been shown to regulate Aβ metabolism, enhance its clearance and alter the processing of its parent molecule, the amyloid precursor protein. This review will discuss underlying mechanisms by which testosterone and LH modulate Aβ and provide an update on therapeutic approaches targeting these hormones.
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Affiliation(s)
- Giuseppe Verdile
- School of Biomedical Sciences, CHIRI Biosciences, Curtin University, Bentley, Western Australia 6102, Australia; Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia 6027, Australia; Sir James McCusker Alzheimer's disease Research Unit, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Crawley, Western Australia 6009, Australia.
| | - Prita R Asih
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia 6027, Australia; Dementia Research Unit, Department of Anatomy, School of Medical Sciences, Faculty of Medicine, University of NSW, Kensington, NSW 2052, Australia
| | - Anna M Barron
- National Institute of Radiological Sciences, Chiba-shi, Chiba 263-8555, Japan
| | - Eka J Wahjoepramono
- Sir James McCusker Alzheimer's disease Research Unit, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Crawley, Western Australia 6009, Australia; Medical Faculty, Pelita Harapan University - Neuroscience Centre, Siloam Hospital, Lippo Karawaci, Tangerang, Indonesia
| | - Lars M Ittner
- Dementia Research Unit, Department of Anatomy, School of Medical Sciences, Faculty of Medicine, University of NSW, Kensington, NSW 2052, Australia; Neuroscience Research Australia, Randwick, NSW 2036, Australia
| | - Ralph N Martins
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia 6027, Australia; Sir James McCusker Alzheimer's disease Research Unit, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Crawley, Western Australia 6009, Australia; School of Biomedical Sciences, CHIRI Biosciences, Curtin University, Bentley, Western Australia 6102, Australia
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20
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Xie J, Wei Q, Deng H, Li G, Ma L, Zeng H. Negative regulation of Grb10 Interacting GYF Protein 2 on insulin-like growth factor-1 receptor signaling pathway caused diabetic mice cognitive impairment. PLoS One 2014; 9:e108559. [PMID: 25268761 PMCID: PMC4182477 DOI: 10.1371/journal.pone.0108559] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 08/25/2014] [Indexed: 12/28/2022] Open
Abstract
Heterozygous Gigyf2⁺/⁻ mice exhibits histopathological evidence of neurodegeneration such as motor dysfunction. Several lines of evidence have demonstrated the important role of insulin-like growth factor-1 receptor (IGF1R) signaling pathway in the neuropathogenic process of cognitive impairment, while decreased Grb10-Interacting GYF Protein 2 (GIGYF2) expression can alter IGF1R trafficking and its downstream signaling pathways. Growth factor receptor-bound protein 10 (Grb10), a suppressor of IGF1R pathway, has been shown to play a critical role in regulating diabetes-associated cognitive impairment. It remains unknown whether endogenous GIGYF2 expression contributes to the development of diabetes-associated cognitive impairment. Using streptozotocin (STZ)-induced diabetic mice model, we first demonstrated that a significantly increased level of GIGYF2 expression was correlated with a significant decrease in the expression of phosphorylated IGF1R as well as the phosphorylation of AKT and ERK1/2, two signaling pathways downstream of IGF1R, in the hippocampus of diabetic mice. On the contrary, in situ knockdown of GIGYF2 expression in hippocampus resulted in increased expression of phosphorylated IGF1R expression and correspondingly reversed the down-regulation of ERK1/2 phsophorylation but had no obvious effect on Grb10 expression. Functionally, knockdown of GIGYF2 expression markedly ameliorated diabetes-associated cognitive dysfunction as well as the ultrastructural pathology and abnormal neurobehavioral changes. These results suggest that increased expression of GIGYF2 might contribute to the development of diabetes-associated cognitive disorder via negatively regulating IGF1R signaling pathway. Therefore, down-regulation of GIGYF2 expression may provide a potential novel approach to treat diabetes-associated cognitive impairment caused by aberrant IGF1R signaling pathway.
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MESH Headings
- Animals
- Carrier Proteins/agonists
- Carrier Proteins/antagonists & inhibitors
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cognition
- Cognition Disorders/complications
- Cognition Disorders/genetics
- Cognition Disorders/physiopathology
- Cognition Disorders/therapy
- Diabetes Mellitus, Experimental/chemically induced
- Diabetes Mellitus, Experimental/complications
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/physiopathology
- GRB10 Adaptor Protein/genetics
- GRB10 Adaptor Protein/metabolism
- Gene Expression Regulation
- Genetic Therapy
- Hippocampus/metabolism
- Hippocampus/physiopathology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mitogen-Activated Protein Kinase 1/genetics
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3/genetics
- Mitogen-Activated Protein Kinase 3/metabolism
- Proto-Oncogene Proteins c-akt/genetics
- Proto-Oncogene Proteins c-akt/metabolism
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- Receptors, Somatomedin/genetics
- Receptors, Somatomedin/metabolism
- Signal Transduction
- Streptozocin
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Affiliation(s)
- Jing Xie
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Qianping Wei
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Huacong Deng
- Department of Endocrinology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Gang Li
- Department of Mental Health, The Mental Health Center of Jiulongpo District, Chongqing, China
| | - Lingli Ma
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Hui Zeng
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Verdile G, Laws SM, Henley D, Ames D, Bush AI, Ellis KA, Faux NG, Gupta VB, Li QX, Masters CL, Pike KE, Rowe CC, Szoeke C, Taddei K, Villemagne VL, Martins RN. Associations between gonadotropins, testosterone and β amyloid in men at risk of Alzheimer's disease. Mol Psychiatry 2014; 19:69-75. [PMID: 23089633 DOI: 10.1038/mp.2012.147] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 08/07/2012] [Accepted: 09/04/2012] [Indexed: 11/09/2022]
Abstract
Testosterone and gonadotropins have been associated with cognitive decline in men and the modulation of β amyloid (Aβ) metabolism. The relatively few studies that have investigated whether changes in one or a combination of these hormones influence Aβ levels have focused primarily on plasma Aβ(1-40) and not on the more pathogenic Aβ(1-42). Currently, no study has investigated whether these hormones are associated with an increase in brain amyloid deposition, ante mortem. Through the highly characterised Australian imaging, biomarkers and lifestyle study, we have determined the impact of these hormones on plasma Aβ levels and brain amyloid burden (Pittsburgh compound B (PiB) retention). Spearman's rank correlation and linear regression analysis was carried out across the cohort and within subclassifications. Luteinizing hormone (LH) was the only variable shown, in the total cohort, to have a significant impact on plasma Aβ(1-40) and Aβ(1-42) levels (beta=0.163, P<0.001; beta=0.446, P<0.001). This held in subjective memory complainers (SMC) (Aβ(1-40); beta=0.208, P=0.017; Aβ(1-42); beta=0.215, P=0.017) but was absent in mild cognitive impairment (MCI) and Alzheimer's disease (AD) groups. In SMC, increased frequency of the APOE-ɛ4 allele (beta=0.536, P<0.001) and increasing serum LH levels (beta=0.421, P=0.004) had a significant impact on PiB retention. Whereas in MCI, PiB retention was associated with increased APOE-ɛ4 allele copy number (beta=0.674, P<0.001) and decreasing calculated free testosterone (beta=-0.303, P=0.043). These findings suggest a potential progressive involvement of LH and testosterone in the early preclinical stages of AD. Furthermore, these hormones should be considered while attempting to predict AD at these earliest stages of the disease.
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Affiliation(s)
- G Verdile
- 1] Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia [2] Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia
| | - S M Laws
- 1] Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia [2] Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia [3] Co-operative Research Centre for Mental Health, http://www.mentalhealthcrc.com
| | - D Henley
- 1] Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia [2] School of Medicine and Pharmacology, University of Western Australia, Crawley, Western Australia, Australia
| | - D Ames
- 1] Academic Unit for Psychiatry of Old Age, Department of Psychiatry, The University of Melbourne, St Vincent's Aged Psychiatry Service, St George's Hospital, Melbourne, Victoria, Australia [2] National Ageing Research Institute, Parkville, Victoria, Australia
| | - A I Bush
- 1] Co-operative Research Centre for Mental Health, http://www.mentalhealthcrc.com [2] Mental Health Research Institute, The University of Melbourne, Parkville, Victoria, Australia [3] Centre for Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
| | - K A Ellis
- 1] Academic Unit for Psychiatry of Old Age, Department of Psychiatry, The University of Melbourne, St Vincent's Aged Psychiatry Service, St George's Hospital, Melbourne, Victoria, Australia [2] National Ageing Research Institute, Parkville, Victoria, Australia [3] Mental Health Research Institute, The University of Melbourne, Parkville, Victoria, Australia
| | - N G Faux
- 1] Mental Health Research Institute, The University of Melbourne, Parkville, Victoria, Australia [2] Centre for Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
| | - V B Gupta
- 1] Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia [2] Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia
| | - Q-X Li
- 1] Mental Health Research Institute, The University of Melbourne, Parkville, Victoria, Australia [2] Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - C L Masters
- 1] Co-operative Research Centre for Mental Health, http://www.mentalhealthcrc.com [2] Mental Health Research Institute, The University of Melbourne, Parkville, Victoria, Australia [3] Centre for Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
| | - K E Pike
- 1] Mental Health Research Institute, The University of Melbourne, Parkville, Victoria, Australia [2] Centre for Neuroscience, The University of Melbourne, Parkville, Victoria, Australia [3] Department of Nuclear Medicine & Centre for PET, Austin Health, Heidelberg, Victoria, Australia [4] School of Psychological Science, La Trobe University, Bundoora, Victoria Australia
| | - C C Rowe
- Department of Nuclear Medicine & Centre for PET, Austin Health, Heidelberg, Victoria, Australia
| | - C Szoeke
- 1] National Ageing Research Institute, Parkville, Victoria, Australia [2] CSIRO, Parkville, Victoria, Australia
| | - K Taddei
- 1] Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia [2] Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia [3] Co-operative Research Centre for Mental Health, http://www.mentalhealthcrc.com
| | - V L Villemagne
- 1] Mental Health Research Institute, The University of Melbourne, Parkville, Victoria, Australia [2] Department of Nuclear Medicine & Centre for PET, Austin Health, Heidelberg, Victoria, Australia
| | - R N Martins
- 1] Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia [2] Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia [3] Co-operative Research Centre for Mental Health, http://www.mentalhealthcrc.com
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22
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Ma L, Wei Q, Deng H, Zhang Q, Li G, Tang N, Xie J, Chen Y. Growth factor receptor-bound protein 10-mediated negative regulation of the insulin-like growth factor-1 receptor-activated signalling pathway results in cognitive disorder in diabetic rats. J Neuroendocrinol 2013; 25:626-34. [PMID: 23614367 DOI: 10.1111/jne.12040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Revised: 03/28/2013] [Accepted: 04/20/2013] [Indexed: 11/29/2022]
Abstract
Growth factor receptor-bound protein 10 (Grb10) is a Src homology 2 domain-containing protein and one of the binding partners for several transmembrane tyrosine kinase receptors, including insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1-R). The hippocampus, which is critical for cognitive functions, is one of the main distribution areas of Grb10 in the central nervous system. In recent years, diabetic encephalopathy has been defined as a third type of diabetes and the IGF1-IR pathway was shown to be critical for the neuropathogenic process of cognitive disorder in diabetes. However, the role of endogenous Grb10 in regulating the IGF1-IR pathway and neurobehavioural changes is not explicit. The present study aimed to determine the in vivo function of endogenous Grb10 in diabetic encephalopathy and the underlying mechanisms. Using stereotaxic surgical techniques and lentiviral vectors expressing specific short hairpin RNA, we could steadily knockdown Grb10 expression in the hippocampus. More importantly, we demonstrated that hippocampus-specific modulation of Grb10 protein levels led to a prominent remission of cognitive disorder, including improvements in both ultrastructural pathology and abnormal neurobehavioural changes. Our findings indicate that endogenous overexpression of Grb10 functions as a suppressor of the IGF1-IR pathway, which may represent an important mechanism for regulating cognitive disorder in diabetes.
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Affiliation(s)
- L Ma
- Department of Gerontology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400042, China
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23
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Human chorionic gonadotropin increases β-cleavage of amyloid precursor protein in SH-SY5Y cells. Cell Mol Neurobiol 2013; 33:747-51. [PMID: 23812658 DOI: 10.1007/s10571-013-9954-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 06/18/2013] [Indexed: 01/02/2023]
Abstract
Elevated levels of amyloid-β (Aβ) peptides, the main component of amyloid plaques in Alzheimer's disease, are the result of excessive β- and γ-cleavage of the amyloid precursor protein (APP) and/or impaired Aβ clearance in the brain. It has been suggested that high concentrations of luteinizing hormone (LH) in women contribute to increased Aβ generation after menopause, but the mechanism for this is incompletely understood. We investigated the effect of human chorionic gonadotropin (hCG), an LH receptor agonist, on APP β-cleavage in the SH-SY5Y neuroblastoma cell line. Treatment of these cells with hCG-induced elevated β-cleavage in a dose-dependent manner: administration of 30 mIU but not 10 mIU/ml of hCG significantly increased sAPPβ levels in the cell medium 1.7-fold as measured by ELISA. These results support the notion that LH contributes to elevated Aβ levels at least in part by increasing β-cleavage of APP by β-site APP cleaving enzyme.
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24
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Clark IA, Atwood CS. Is TNF a link between aging-related reproductive endocrine dyscrasia and Alzheimer's disease? J Alzheimers Dis 2012; 27:691-9. [PMID: 21891866 DOI: 10.3233/jad-2011-110887] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This commentary addresses a novel mechanism by which aging-related changes in reproductive hormones could mediate their action in the brain. It presents the evidence that dyotic endocrine signals modulate the expression of tumor necrosis factor (TNF) and related cytokines, and that these cytokines are a functionally important downstream link mediating neurodegeneration and dysfunction. This convergence of dyotic signaling on TNF-mediated degeneration and dysfunction has important implications for understanding the pathophysiology of AD, stroke, and traumatic brain disease, and also for the treatment of these diseases.
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Affiliation(s)
- Ian A Clark
- Research School of Biology, Australian National University, Canberra, ACT, Australia.
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25
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Abstract
A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.
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Affiliation(s)
- Anna M. Barron
- USC Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089 USA
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 153-8902 Japan
| | - Christian J. Pike
- USC Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089 USA
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26
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Barron AM, Pike CJ. Sex hormones, aging, and Alzheimer's disease. Front Biosci (Elite Ed) 2012. [PMID: 22201929 DOI: 10.2741/434] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.
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Affiliation(s)
- Anna M Barron
- USC Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089 USA
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27
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Wolf-Ringwall AL, Winter PW, Liu J, Van Orden AK, Roess DA, Barisas BG. Restricted lateral diffusion of luteinizing hormone receptors in membrane microdomains. J Biol Chem 2011; 286:29818-27. [PMID: 21690095 DOI: 10.1074/jbc.m111.250969] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Single particle tracking was used to evaluate lateral motions of individual FLAG-tagged human luteinizing hormone (LH) receptors expressed on CHO cells and native LH receptors on both KGN human granulosa-derived tumor cells and M17 human neuroblastoma cells before and after exposure to human chorionic gonadotropin (hCG). Compared with LH receptors on untreated cells, LH receptors on cells treated with 100 nm hCG exhibit restricted lateral diffusion and are confined in small, nanometer-scale, membrane compartments. Similar to LH receptors labeled with Au-hCG, LH receptors labeled with gold-deglycosylated hCG, an hCG antagonist, also exhibit restricted lateral diffusion and are confined in nanoscale membrane compartments on KGN cells treated with 100 nm hCG. LH receptor point mutants lacking potential palmitoylation sites remain in large compartments despite treatment with 100 nm hCG as do LH receptors on cells treated with cytochalasin D. Finally, both polarization homotransfer fluorescence resonance energy transfer imaging and photon counting histogram analysis indicate that treatment with hCG induces aggregation of YFP-coupled LH receptors stably expressed on CHO cells. Taken together, our results demonstrate that binding of hCG induces aggregation of LH receptors within nanoscale, cell surface membrane compartments, that hCG binding also affects the lateral motions of antagonist binding LH receptors, and that receptor surface densities must be considered in evaluating the extent of hormone-dependent receptor aggregation.
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Affiliation(s)
- Amber L Wolf-Ringwall
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado 80523, USA
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28
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Wahjoepramono EJ, Wijaya LK, Taddei K, Bates KA, Howard M, Martins G, deRuyck K, Matthews PM, Verdile G, Martins RN. Direct exposure of guinea pig CNS to human luteinizing hormone increases cerebrospinal fluid and cerebral beta amyloid levels. Neuroendocrinology 2011; 94:313-22. [PMID: 21985789 DOI: 10.1159/000330812] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 06/28/2011] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS Luteinizing hormone (LH) has been shown to alter the metabolism of beta amyloid (Aβ), a key protein in Alzheimer's disease (AD) pathogenesis. While LH and components required for LH receptor signalling are present in the brain, their role in the CNS remains unclear. In vitro, LH has been shown to facilitate neurosteroid production and alter Aβ metabolism. However, whether LH can directly modulate cerebral Aβ levels in vivo has not previously been studied. In this study, we investigated the effect of chronic administration of LH to the guinea pig CNS on cerebral Aβ levels. METHODS Gonadectomised male animals were administered, via cortical placement, either placebo or LH slow-release pellets. At 14 and 28 days after treatment, animals were sacrificed. Brain, plasma and CSF were collected and Aβ levels measured via ELISA. Levels of the Aβ precursor protein (APP) and the neurosteroidogenic enzyme cytochrome P450 side-chain cleavage enzyme (P450scc) were also assayed. RESULTS An increase in CSF Aβ40 levels was observed 28 days following treatment. These CSF data also reflected changes in Aβ40 levels observed in brain homogenates. No change was observed in plasma Aβ40 levels but APP and its C-terminal fragments (APP-CTF) were significantly increased in response to LH exposure. Protein expression of P450scc was increased after 28 days of LH exposure, suggesting activation of the LH receptor. CONCLUSION These data indicate that direct exposure of guinea pig CNS to LH results in altered brain Aβ levels, perhaps due to altered APP expression/metabolism.
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Affiliation(s)
- Eka J Wahjoepramono
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
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