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Sitruk-Ware R, Sussman H, Brinton R, Schumacher M, Singer P, Kumar N, De Nicola AF, El-Etr M, Guennoun R, V Borlongan C. Nestorone (segesterone acetate) effects on neuroregeneration. Front Neuroendocrinol 2024; 73:101136. [PMID: 38670433 DOI: 10.1016/j.yfrne.2024.101136] [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: 02/23/2024] [Revised: 04/08/2024] [Accepted: 04/22/2024] [Indexed: 04/28/2024]
Abstract
Nestorone® (segesterone acetate) is a progestin with a chemical structure closely related to progesterone with high affinity and selectivity for the progesterone receptor without significant interaction with other steroid receptors. It has been developed for female and male contraception and is FDA-approved in a first long-acting contraceptive vaginal system for female contraception. Its safety has been extensively demonstrated in both preclinical and clinical studies for contraceptive indications. Nestorone was found to display neuroprotective and neuroregenerative activity in animal models of various central nervous system diseases, including multiple sclerosis, stroke, and amyotrophic lateral sclerosis. Reviewed herein are neuroprotective and myelin- regenerating properties of Nestorone in various animal models and its translational potential as a therapeutic agent for debilitating neurological diseases for which limited therapeutic options are available (Table 1).
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Affiliation(s)
| | | | - Roberta Brinton
- Center for Innovation in Brain Science, Tucson, AZ, United States
| | | | | | | | | | - Martine El-Etr
- U1195 Inserm and University Paris-Saclay Le Kremlin Bicêtre, France
| | - Rachida Guennoun
- U1195 Inserm and University Paris-Saclay Le Kremlin Bicêtre, France
| | - Cesar V Borlongan
- Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, FL, USA
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Gonzalez Deniselle MC, Bettini M, Garrido RM, Meyer M, Lara A, Garay LI, Casas S, Fulgenzi E, Nuñez M, Rugiero MF, De Nicola AF, Gargiulo-Monachelli G. Exposure to endogenous and exogenous sex hormones and reproductive history influence prognosis in women with ALS. Muscle Nerve 2023; 68:414-421. [PMID: 37493444 DOI: 10.1002/mus.27942] [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: 01/28/2023] [Revised: 07/03/2023] [Accepted: 07/08/2023] [Indexed: 07/27/2023]
Abstract
INTRODUCTION/AIMS Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with a higher incidence in men suggesting an influence of sex steroids. Our objective was to investigate past exposure to endogenous and synthetic steroids in female ALS patients and controls. METHODS We administered a questionnaire to 158 postmenopausal women (75 ALS patients and 83 controls). We calculated reproductive time span (RTS), lifetime endogenous estrogen (LEE) and progesterone exposures (LPE), oral contraceptive pill (OCP) use, and reproductive history. RESULTS ALS patients showed shorter LEE and LPE, a lower proportion of breast cancer, and 11% showed no history of pregnancies vs. 4% of controls. Odds ratios (ORs) showed that <17 y of LEE and a delayed menarche (>13 y) constitute risk factors for ALS [OR = 2.1 (95% confidence interval {CI}, 1.08-4.2); and OR = 2.4 (95% CI, 1.1-5.1) respectively]. According to Cox survival analysis, for each year the LEE increased over 17 y, it was independently associated with longer survival [hazard ratio (HR) = 0.37 (95% CI, 0.16-0.85)] after adjusting for smoking, age and site of onset. Multivariate regression analysis demonstrated that for each month using OCP for longer than 40 mo increased the risk of ALS [adjusted OR = 4.1 (95% CI, 1.2-13.8)]. DISCUSSION Thus, longer exposure to endogenous female sex steroids increased survival and reduced ALS susceptibility. In contrast, longer exposure to synthetic sex steroids showed a negative impact by reducing the production of endogenous female sex steroids or due to crossover with other steroid receptors. Given the neuroprotective effects of sex steroids, we suggest that abnormalities of neuroendocrine components may alter motor function in women with ALS.
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Affiliation(s)
- M Claudia Gonzalez Deniselle
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Buenos Aires, Argentina
- Department of Physiological Sciences, Faculty of Medicine, University of Buenos Aires, Buenos Aires, Argentina
| | - Mariela Bettini
- Department of Neurology, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina
| | - Rosa M Garrido
- Department of Gynecology, Hospital Marie Curie, Buenos Aires, Argentina
| | - Maria Meyer
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Buenos Aires, Argentina
| | - Agustina Lara
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Buenos Aires, Argentina
| | - Laura I Garay
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Buenos Aires, Argentina
- Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Buenos Aires, Argentina
| | - Sebastian Casas
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Buenos Aires, Argentina
- Department of Neurology, Hospital Militar Central Cirujano Mayor Dr. Cosme Argerich, Buenos Aires, Argentina
| | - Ernesto Fulgenzi
- Hospital General de Agudos Dr. Ignacio Pirovano, Buenos Aires, Argentina
| | - Myriam Nuñez
- Department of Physics Mathematics, Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina
| | - Marcelo F Rugiero
- Department of Gynecology, Hospital Marie Curie, Buenos Aires, Argentina
| | - Alejandro F De Nicola
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Buenos Aires, Argentina
- Department of Neurology, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina
| | - Gisella Gargiulo-Monachelli
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Buenos Aires, Argentina
- Department of Neurology, Hospital General de Agudos Juan A. Fernández, Buenos Aires, Argentina
- Department of Neurology, Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno", CEMIC, Buenos Aires, Argentina
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Lucchi C, Codeluppi A, Filaferro M, Vitale G, Rustichelli C, Avallone R, Mandrioli J, Biagini G. Human Microglia Synthesize Neurosteroids to Cope with Rotenone-Induced Oxidative Stress. Antioxidants (Basel) 2023; 12:antiox12040963. [PMID: 37107338 PMCID: PMC10135967 DOI: 10.3390/antiox12040963] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/05/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
We obtained evidence that mouse BV2 microglia synthesize neurosteroids dynamically to modify neurosteroid levels in response to oxidative damage caused by rotenone. Here, we evaluated whether neurosteroids could be produced and altered in response to rotenone by the human microglial clone 3 (HMC3) cell line. To this aim, HMC3 cultures were exposed to rotenone (100 nM) and neurosteroids were measured in the culture medium by liquid chromatography with tandem mass spectrometry. Microglia reactivity was evaluated by measuring interleukin 6 (IL-6) levels, whereas cell viability was monitored by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. After 24 h (h), rotenone increased IL-6 and reactive oxygen species levels by approximately +37% over the baseline, without affecting cell viability; however, microglia viability was significantly reduced at 48 h (p < 0.01). These changes were accompanied by the downregulation of several neurosteroids, including pregnenolone, pregnenolone sulfate, 5α-dihydroprogesterone, and pregnanolone, except for allopregnanolone, which instead was remarkably increased (p < 0.05). Interestingly, treatment with exogenous allopregnanolone (1 nM) efficiently prevented the reduction in HMC3 cell viability. In conclusion, this is the first evidence that human microglia can produce allopregnanolone and that this neurosteroid is increasingly released in response to oxidative stress, to tentatively support the microglia's survival.
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Affiliation(s)
- Chiara Lucchi
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Alessandro Codeluppi
- Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Monica Filaferro
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Giovanni Vitale
- Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Cecilia Rustichelli
- Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Rossella Avallone
- Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Jessica Mandrioli
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
- Department of Neurosciences, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, 41126 Modena, Italy
| | - Giuseppe Biagini
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
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Ferreyra S, González S. Therapeutic potential of progesterone in spinal cord injury-induced neuropathic pain: At the crossroads between neuroinflammation and N-methyl-D-aspartate receptor. J Neuroendocrinol 2023; 35:e13181. [PMID: 35924434 DOI: 10.1111/jne.13181] [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: 04/27/2022] [Revised: 06/13/2022] [Accepted: 06/19/2022] [Indexed: 10/17/2022]
Abstract
In recent decades, an area of active research has supported the notion that progesterone promotes a wide range of remarkable protective actions in experimental models of nervous system trauma or disease, and has also provided a strong basis for considering this steroid as a promising molecule for modulating the complex maladaptive changes that lead to neuropathic pain, especially after spinal cord injury. In this review, we intend to give the readers a brief appraisal of the main mechanisms underlying the increased excitability of the spinal circuit in the pain pathway after trauma, with particular emphasis on those mediated by the activation of resident glial cells, the subsequent release of proinflammatory cytokines and their impact on N-methyl-D-aspartate receptor function. We then summarize the available preclinical data pointing to progesterone as a valuable repurposing molecule for blocking critical cellular and molecular events that occur in the dorsal horn of the injured spinal cord and are related to the development of chronic pain. Since the treatment and management of neuropathic pain after spinal injury remains challenging, the potential therapeutic value of progesterone opens new traslational perspectives to prevent central pain.
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Affiliation(s)
- Sol Ferreyra
- Instituto de Biología y Medicina Experimental, Laboratorio de Nocicepción y Dolor Neuropático, CONICET, Buenos Aires, Argentina
| | - Susana González
- Instituto de Biología y Medicina Experimental, Laboratorio de Nocicepción y Dolor Neuropático, CONICET, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Buenos Aires, Argentina
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Proaño B, Casani-Cubel J, Benlloch M, Rodriguez-Mateos A, Navarro-Illana E, Lajara-Romance JM, de la Rubia Ortí JE. Is Dutasteride a Therapeutic Alternative for Amyotrophic Lateral Sclerosis? Biomedicines 2022; 10:biomedicines10092084. [PMID: 36140184 PMCID: PMC9495995 DOI: 10.3390/biomedicines10092084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/17/2022] [Accepted: 08/23/2022] [Indexed: 11/24/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that is characterized by the loss of upper and lower motor neurons (MNs) in the cerebral cortex, brainstem and spinal cord, with consequent weakness, atrophy and the progressive paralysis of all muscles. There is currently no medical cure, and riluzole and edaravone are the only two known approved drugs for treating this condition. However, they have limited efficacy, and hence there is a need to find new molecules. Dutasteride, a dual inhibitor of type 1 and type 2 5α-reductase (5AR) enzymes, the therapeutic purposes of which, to date, are the treatment of benign prostatic hyperplasia and androgenic alopecia, shows great anti-ALS properties by the molecular-topology methodology. Based on this evidence, this review aims to assess the effects of dutasteride on testosterone (T), progesterone (PROG) and 17β-estradiol (17BE) as a therapeutic alternative for the clinical improvement of ALS, based on the hormonal, metabolic and molecular pathways related to the pathogenesis of the disease. According to the evidence found, dutasteride shows great neuroprotective, antioxidant and anti-inflammatory effects. It also appears effective against glutamate toxicity, and it is capable of restoring altered dopamine activity (DA). These effects are achieved both directly and through steroid hormones. Therefore, dutasteride seems to be a promising molecule for the treatment of ALS, although clinical studies are required for confirmation.
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Affiliation(s)
- Belén Proaño
- Doctoral Degree School, Health Sciences, Catholic University of Valencia San Vicente Mártir, 46001 Valencia, Spain
| | - Julia Casani-Cubel
- School of Medicine and Health Sciences, Catholic University San Vicente Mártir, 46001 Valencia, Spain
- Correspondence: (J.C.-C.); (M.B.)
| | - María Benlloch
- Department Nursing, Catholic University San Vicente Mártir, 46001 Valencia, Spain
- Correspondence: (J.C.-C.); (M.B.)
| | - Ana Rodriguez-Mateos
- Department of Nutritional Sciences, King’s College London, Franklin Wilkins Building, London SE1 9NH, UK
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Raikes AC, Hernandez GD, Matthews DC, Lukic AS, Law M, Shi Y, Schneider LS, Brinton RD. Exploratory imaging outcomes of a phase 1b/2a clinical trial of allopregnanolone as a regenerative therapeutic for Alzheimer's disease: Structural effects and functional connectivity outcomes. ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2022; 8:e12258. [PMID: 35310526 PMCID: PMC8919249 DOI: 10.1002/trc2.12258] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/18/2021] [Accepted: 12/21/2021] [Indexed: 01/14/2023]
Abstract
Introduction Allopregnanolone (ALLO), an endogenous neurosteroid, promoted neurogenesis and oligogenesis and restored cognitive function in animal models of Alzheimer's disease (AD). Based on these discovery research findings, we conducted a randomized-controlled phase 1b/2a multiple ascending dose trial of ALLO in persons with early AD (NCT02221622) to assess safety, tolerability, and pharmacokinetics. Exploratory imaging outcomes to determine whether ALLO impacted hippocampal structure, white matter integrity, and functional connectivity are reported. Methods Twenty-four individuals participated in the trial (n = 6 placebo; n = 18 ALLO) and underwent brain magnetic resonance imaging (MRI) before and after 12 weeks of treatment. Hippocampal atrophy rate was determined from volumetric MRI, computed as rate of change, and qualitatively assessed between ALLO and placebo sex, apolipoprotein E (APOE) ε4 allele, and ALLO dose subgroups. White matter microstructural integrity was compared between placebo and ALLO using fractional and quantitative anisotropy (QA). Changes in local, inter-regional, and network-level functional connectivity were also compared between groups using resting-state functional MRI. Results Rate of decline in hippocampal volume was slowed, and in some cases reversed, in the ALLO group compared to placebo. Gain of hippocampal volume was evident in APOE ε4 carriers (range: 0.6% to 7.8% increased hippocampal volume). Multiple measures of white matter integrity indicated evidence of preserved or improved integrity. ALLO significantly increased fractional anisotropy (FA) in 690 of 690 and QA in 1416 of 1888 fiber tracts, located primarily in the corpus callosum, bilateral thalamic radiations, and bilateral corticospinal tracts. Consistent with structural changes, ALLO strengthened local, inter-regional, and network level functional connectivity in AD-vulnerable regions, including the precuneus and posterior cingulate, and network connections between the default mode network and limbic system. Discussion Indicators of regeneration from previous preclinical studies and these exploratory MRI-based outcomes from this phase 1b/2a clinical cohort support advancement to a phase 2 proof-of-concept efficacy clinical trial of ALLO as a regenerative therapeutic for mild AD (REGEN-BRAIN study; NCT04838301).
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Affiliation(s)
- Adam C. Raikes
- Center for Innovation in Brain ScienceUniversity of ArizonaTucsonArizonaUSA
| | | | - Dawn C. Matthews
- Departments of Pharmacology and Neurology, College of MedicineADM DiagnosticsNorthbrookIllinoisUSA
| | - Ana S. Lukic
- Departments of Pharmacology and Neurology, College of MedicineADM DiagnosticsNorthbrookIllinoisUSA
| | - Meng Law
- Department of RadiologyAlfred HealthDepartment of Neuroscience and Computer Systems EngineeringMonash UniversityMelbourneAustralia
| | - Yonggang Shi
- Stevens Neuroimaging and Informatics InstituteKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Lon S. Schneider
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Roberta D. Brinton
- Center for Innovation in Brain ScienceUniversity of ArizonaTucsonArizonaUSA
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Neudecker V, Perez-Zoghbi JF, Brambrink AM. Does inflammation mediate behavioural alterations in anaesthesia-induced developmental neurotoxicity? Br J Anaesth 2022; 128:602-605. [PMID: 35115157 DOI: 10.1016/j.bja.2021.12.040] [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: 11/16/2021] [Revised: 12/14/2021] [Accepted: 12/24/2021] [Indexed: 11/30/2022] Open
Abstract
Anaesthesia exposure early in life potentially impairs neurobehavioural development. A recent study in the Journal investigated the possibility that progesterone mitigates anaesthesia-induced developmental neurotoxicity in neonatal rats exposed to sevoflurane. The novel findings show that the steroid hormone progesterone protects against development of behavioural alterations caused by sevoflurane. The protective mechanism is proposed to relate to anti-inflammatory properties of progesterone, which brings up important questions regarding the role of inflammation in mediating the neurobehavioural alterations in anaesthesia-induced developmental neurotoxicity. We discuss this mechanism and encourage new research that may clarify the underlying mechanisms of progesterone-induced protection and extend these findings into a translational model.
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Affiliation(s)
- Viola Neudecker
- Department of Anesthesiology, Columbia University Medical Center, New York, NY, USA
| | - Jose F Perez-Zoghbi
- Department of Anesthesiology, Columbia University Medical Center, New York, NY, USA
| | - Ansgar M Brambrink
- Department of Anesthesiology, Columbia University Medical Center, New York, NY, USA.
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Translocator Protein Ligand PIGA1138 Reduces Disease Symptoms and Severity in Experimental Autoimmune Encephalomyelitis Model of Primary Progressive Multiple Sclerosis. Mol Neurobiol 2022; 59:1744-1765. [PMID: 35018577 DOI: 10.1007/s12035-022-02737-2] [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: 10/30/2021] [Accepted: 01/04/2022] [Indexed: 10/19/2022]
Abstract
Multiple sclerosis (MS) is an autoimmune and demyelinating disease of the central nervous system (CNS) caused by CNS infiltration of peripheral immune cells, immune-mediated attack of the myelin sheath, neuroinflammation, and/or axonal/neuronal dysfunctions. Some drugs are available to cope with relapsing-remitting MS (RRMS) but there is no therapy for the primary progressive MS (PPMS). Because growing evidence supports a regulatory role of the translocator protein (TSPO) in neuroinflammatory, demyelinating, and neurodegenerative processes, we investigated the therapeutic potential of phenylindolyilglyoxylamydes (PIGAs) TSPO ligands in myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) mice mimicking the human PPMS. MOG-EAE C57Bl/6-mice were treated by TSPO ligands PIGA839, PIGA1138, or the vehicle. Several methods were combined to evaluate PIGAs-TSPO ligand effects on MOG-EAE symptoms, CNS infiltration by immune cells, demyelination, and axonal damages. PIGA1138 (15 mg/kg) drastically reduced MOG-EAE mice clinical scores, ameliorated motor dysfunctions assessed with the Catwalk device, and counteracted MOG-EAE-induced demyelination by preserving Myelin basic protein (MBP) expression in the CNS. Furthermore, PIGA1138-treatment prevented EAE-evoked decreased neurofilament-200 expression in spinal and cerebellar axons. Moreover, PIGA1138 inhibited peripheral immune-CD45 + cell infiltration in the CNS, suggesting that it may control inflammatory mechanisms involved in PPMS. Concordantly, PIGA1138 enhanced anti-inflammatory interleukin-10 serum level in MOG-EAE mice. PIGA1138-treatment, which increased neurosteroid allopregnanolone production, ameliorated all pathological biomarkers, while PIGA839, unable to activate neurosteroidogenesis in vivo, exerted only moderate/partial effects in MOG-EAE mice. Altogether, our results suggest that PIGA1138-based treatment may represent an interesting possibility to be explored for the innovation of effective therapies against PPMS.
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Wilkinson EC, Starke EL, Barbee SA. Vps54 Regulates Lifespan and Locomotor Behavior in Adult Drosophila melanogaster. Front Genet 2021; 12:762012. [PMID: 34712272 PMCID: PMC8546322 DOI: 10.3389/fgene.2021.762012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/28/2021] [Indexed: 11/13/2022] Open
Abstract
Vps54 is an integral subunit of the Golgi-associated retrograde protein (GARP) complex, which is involved in tethering endosome-derived vesicles to the trans-Golgi network (TGN). A destabilizing missense mutation in Vps54 causes the age-progressive motor neuron (MN) degeneration, muscle weakness, and muscle atrophy observed in the wobbler mouse, an established animal model for human MN disease. It is currently unclear how the disruption of Vps54, and thereby the GARP complex, leads to MN and muscle phenotypes. To develop a new tool to address this question, we have created an analogous model in Drosophila by generating novel loss-of-function alleles of the fly Vps54 ortholog (scattered/scat). We find that null scat mutant adults are viable but have a significantly shortened lifespan. Like phenotypes observed in the wobbler mouse, we show that scat mutant adults are male sterile and have significantly reduced body size and muscle area. Moreover, we demonstrate that scat mutant adults have significant age-progressive defects in locomotor function. Interestingly, we see sexually dimorphic effects, with scat mutant adult females exhibiting significantly stronger phenotypes. Finally, we show that scat interacts genetically with rab11 in MNs to control age-progressive muscle atrophy in adults. Together, these data suggest that scat mutant flies share mutant phenotypes with the wobbler mouse and may serve as a new genetic model system to study the cellular and molecular mechanisms underlying MN disease.
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Affiliation(s)
- Emily C Wilkinson
- Department of Biological Sciences, University of Denver, Denver, CO, United States
| | - Emily L Starke
- Department of Biological Sciences, University of Denver, Denver, CO, United States
| | - Scott A Barbee
- Department of Biological Sciences, University of Denver, Denver, CO, United States.,Molecular and Cellular Biophysics Program, University of Denver, Denver, CO, United States
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