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Rong J, Yang Y, Liang M, Zhong H, Li Y, Zhu Y, Sha S, Chen L, Zhou R. Neonatal inflammation increases hippocampal KCC2 expression through methylation-mediated TGF-β1 downregulation leading to impaired hippocampal cognitive function and synaptic plasticity in adult mice. J Neuroinflammation 2023; 20:15. [PMID: 36691035 PMCID: PMC9872321 DOI: 10.1186/s12974-023-02697-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 01/12/2023] [Indexed: 01/25/2023] Open
Abstract
The mechanisms by which neonatal inflammation leads to cognitive deficits in adulthood remain poorly understood. Inhibitory GABAergic synaptic transmission plays a vital role in controlling learning, memory and synaptic plasticity. Since early-life inflammation has been reported to adversely affect the GABAergic synaptic transmission, the aim of this study was to investigate whether and how neonatal inflammation affects GABAergic synaptic transmission resulting in cognitive impairment. Neonatal mice received a daily subcutaneous injection of lipopolysaccharide (LPS, 50 μg/kg) or saline on postnatal days 3-5. It was found that blocking GABAergic synaptic transmission reversed the deficit in hippocampus-dependent memory or the induction failure of long-term potentiation in the dorsal CA1 in adult LPS mice. An increase of mIPSCs amplitude was further detected in adult LPS mice indicative of postsynaptic potentiation of GABAergic transmission. Additionally, neonatal LPS resulted in the increased expression and function of K+-Cl--cotransporter 2 (KCC2) and the decreased expression of transforming growth factor-beta 1 (TGF-β1) in the dorsal CA1 during adulthood. The local TGF-β1 overexpression improved KCC2 expression and function, synaptic plasticity and memory of adult LPS mice. Adult LPS mice show hypermethylation of TGFb1 promoter and negatively correlate with reduced TGF-β1 transcripts. 5-Aza-deoxycytidine restored the changes in TGFb1 promoter methylation and TGF-β1 expression. Altogether, the results suggest that hypermethylation-induced reduction of TGF-β1 leads to enhanced GABAergic synaptic inhibition through increased KCC2 expression, which is a underlying mechanism of neonatal inflammation-induced hippocampus-dependent memory impairment in adult mice.
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Affiliation(s)
- Jing Rong
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Yang Yang
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Min Liang
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Haiquan Zhong
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Yingchun Li
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Yichao Zhu
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Sha Sha
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Lei Chen
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Rong Zhou
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
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Reddy DS. Neurosteroid replacement therapy for catamenial epilepsy, postpartum depression and neuroendocrine disorders in women. J Neuroendocrinol 2022; 34:e13028. [PMID: 34506047 PMCID: PMC9247111 DOI: 10.1111/jne.13028] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/27/2021] [Accepted: 08/05/2021] [Indexed: 12/11/2022]
Abstract
Neurosteroids are involved in the pathophysiology of many neuroendocrine disorders in women. This review describes recent advancements in pharmacology of neurosteroids and emphasizes the benefits of neurosteroid replacement therapy for the management of neuroendocrine disorders such as catamenial epilepsy (CE), postpartum depression (PPD) and premenstrual brain conditions. Neurosteroids are endogenous modulators of neuronal excitability. A variety of neurosteroids are present in the brain including allopregnanolone (AP), allotetrahydro-deoxycorticosterone and androstanediol. Neurosteroids interact with synaptic and extrasynaptic GABAA receptors in the brain. AP and related neurosteroids, which are positive allosteric modulators of GABAA receptors, are powerful anticonvulsants, anxiolytic, antistress and neuroprotectant agents. In CE, seizures are most often clustered around a specific menstrual period in women. Neurosteroid withdrawal-linked plasticity in extrasynaptic receptors has been shown to play a key role in catamenial seizures, anxiety and other mood disorders. Based on our extensive research spanning two decades, we have proposed and championed neurosteroid replacement therapy as a rational strategy for treating disorders marked by neurosteroid-deficiency, such as CE and other related ovarian or menstrual disorders. In 2019, AP (renamed as brexanolone) was approved for treating PPD. A variety of synthetic neurosteroids are in clinical trials for epilepsy, depression and other brain disorders. Recent advancements in our understanding of neurosteroids have entered a new era of drug discovery and one that offers a high therapeutic potential for treating complex brain disorders.
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Affiliation(s)
- Doodipala Samba Reddy
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University College of Medicine, Bryan, TX, USA
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Hornung RS, Benton WL, Tongkhuya S, Uphouse L, Kramer PR, Averitt DL. Progesterone and Allopregnanolone Rapidly Attenuate Estrogen-Associated Mechanical Allodynia in Rats with Persistent Temporomandibular Joint Inflammation. Front Integr Neurosci 2020; 14:26. [PMID: 32457584 PMCID: PMC7225267 DOI: 10.3389/fnint.2020.00026] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 04/15/2020] [Indexed: 12/16/2022] Open
Abstract
Temporomandibular joint disorder (TMD) is associated with pain in the joint (temporomandibular joint, TMJ) and muscles involved in mastication. TMD pain dissipates following menopause but returns in some women undergoing estrogen replacement therapy. Progesterone has both anti-inflammatory and antinociceptive properties, while estrogen's effects on nociception are variable and highly dependent on both natural hormone fluctuations and estrogen dosage during pharmacological treatments, with high doses increasing pain. Allopregnanolone, a progesterone metabolite and positive allosteric modulator of the GABAA receptor, also has antinociceptive properties. While progesterone and allopregnanolone are antinociceptive, their effect on estrogen-exacerbated TMD pain has not been determined. We hypothesized that removing the source of endogenous ovarian hormones would reduce inflammatory allodynia in the TMJ of rats and both progesterone and allopregnanolone would attenuate the estrogen-provoked return of allodynia. Baseline mechanical sensitivity was measured in female Sprague-Dawley rats (150-175 g) using the von Frey filament method followed by a unilateral injection of complete Freund's adjuvant (CFA) into the TMJ. Mechanical allodynia was confirmed 24 h later; then rats were ovariectomized or received sham surgery. Two weeks later, allodynia was reassessed and rats received one of the following subcutaneous hormone treatments over 5 days: a daily pharmacological dose of estradiol benzoate (E2; 50 μg/kg), daily E2 and pharmacological to sub-physiological doses of progesterone (P4; 16 mg/kg, 16 μg/kg, or 16 ng/kg), E2 daily and interrupted P4 given every other day, daily P4, or daily vehicle control. A separate group of animals received allopregnanolone (0.16 mg/kg) instead of P4. Allodynia was reassessed 1 h following injections. Here, we report that CFA-evoked mechanical allodynia was attenuated following ovariectomy and daily high E2 treatment triggered the return of allodynia, which was rapidly attenuated when P4 was also administered either daily or every other day. Allopregnanolone treatment, whether daily or every other day, also attenuated estrogen-exacerbated allodynia within 1 h of treatment, but only on the first treatment day. These data indicate that when gonadal hormone levels have diminished, treatment with a lower dose of progesterone may be effective at rapidly reducing the estrogen-evoked recurrence of inflammatory mechanical allodynia in the TMJ.
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Affiliation(s)
- Rebecca S. Hornung
- Department of Biology, Texas Woman’s University, Denton, TX, United States
| | - William L. Benton
- Department of Biology, Texas Woman’s University, Denton, TX, United States
| | - Sirima Tongkhuya
- Department of Biology, Texas Woman’s University, Denton, TX, United States
| | - Lynda Uphouse
- Department of Biology, Texas Woman’s University, Denton, TX, United States
| | - Phillip R. Kramer
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, United States
| | - Dayna Loyd Averitt
- Department of Biology, Texas Woman’s University, Denton, TX, United States
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Hedström H, Bäckström T, Bixo M, Nyberg S, Wang M, Gideonsson I, Turkmen S. Women with polycystic ovary syndrome have elevated serum concentrations of and altered GABA(A) receptor sensitivity to allopregnanolone. Clin Endocrinol (Oxf) 2015; 83:643-50. [PMID: 25929428 DOI: 10.1111/cen.12809] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 03/18/2015] [Accepted: 04/23/2015] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Several studies have reported that γ-aminobutyric acid (GABA) ergic circuits are involved in the pathophysiology of polycystic ovary syndrome (PCOS). The progesterone metabolite allopregnanolone is a potent GABA(A) -receptor-modulating steroid, and patients may have increased concentrations of allopregnanolone or altered GABAA receptor sensitivity. We investigated both of these possibilities in this study. PATIENTS We enrolled 9 women with PCOS and 24 age-matched eumenorrhoeic controls, who were divided into two groups by body mass index (BMI) (16 normal weight and 8 overweight). MEASUREMENTS We investigated the effects of allopregnanolone injection on GABA(A) receptor sensitivity in both groups of women. All women received a single intravenous dose of allopregnanolone (0·050 mg/kg). GABA(A) receptor sensitivity was assessed with the saccadic eye velocity (SEV) over 30° (SEV30°), the SEV30°/allopregnanolone concentration ([Allo]) ratio, and sedation, which were measured together with serum allopregnanolone at intervals for 180 min after injection. The controls were tested in the follicular phase of the menstrual cycle. RESULTS Baseline allopregnanolone concentrations were higher in the PCOS women than in the normal-weight (P = 0·034) and overweight controls (P = 0·004). The allopregnanolone concentrations after injection were higher in the PCOS women (P = 0·006) and overweight controls (P = 0·037) than in the normal-weight controls. All groups showed a decline in the SEV30°/[Allo] ratio after injection. Allopregnanolone had a smaller effect on the SEV30°/[Allo] ratio in the overweight women (PCOS, P = 0·032; controls, P = 0·007) than in the normal-weight controls. The sedation score after allopregnanolone injection was lower in the PCOS patients than in the controls, but was not different between the two control groups. CONCLUSIONS PCOS women had elevated baseline allopregnanolone concentrations compared with follicular-phase controls. All overweight women (PCOS and controls) were less sensitive to allopregnanolone than normal-weight controls.
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Affiliation(s)
- Helena Hedström
- Department of Clinical Science, Obstetrics and Gynecology, Umeå Neurosteroid Research Center, Umeå University, Umeå, Sweden
| | - Torbjörn Bäckström
- Department of Clinical Science, Obstetrics and Gynecology, Umeå Neurosteroid Research Center, Umeå University, Umeå, Sweden
| | - Marie Bixo
- Department of Clinical Science, Obstetrics and Gynecology, Umeå Neurosteroid Research Center, Umeå University, Umeå, Sweden
| | - Sigrid Nyberg
- Department of Clinical Science, Obstetrics and Gynecology, Umeå Neurosteroid Research Center, Umeå University, Umeå, Sweden
| | - Mingde Wang
- Department of Clinical Science, Obstetrics and Gynecology, Umeå Neurosteroid Research Center, Umeå University, Umeå, Sweden
| | - Ida Gideonsson
- Department of Clinical Science, Obstetrics and Gynecology, Umeå Neurosteroid Research Center, Umeå University, Umeå, Sweden
| | - Sahruh Turkmen
- Department of Clinical Science, Obstetrics and Gynecology, Umeå Neurosteroid Research Center, Umeå University, Umeå, Sweden
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Gauvin DV, Zimmermann ZJ, Baird TJ. Preclinical assessment of abuse liability of biologics: In defense of current regulatory control policies. Regul Toxicol Pharmacol 2015; 73:43-54. [DOI: 10.1016/j.yrtph.2015.06.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 06/11/2015] [Accepted: 06/12/2015] [Indexed: 01/16/2023]
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Tolerance to the rate-increasing and not rate-decreasing effects of pregnanolone in rats. Behav Pharmacol 2014; 21:736-44. [PMID: 20859199 DOI: 10.1097/fbp.0b013e32833fa79d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Chronic treatment with benzodiazepines, which positively modulate γ-aminobutyric acidA (GABAA) receptors, can lead to the development of tolerance. Similar effects might also occur during chronic treatment with positive modulators acting at other sites on GABAA receptors (e.g. neuroactive steroids). In this study, tolerance and cross tolerance were examined in seven rats treated daily with the neuroactive steroid pregnanolone (25.6 mg/kg/day) and responding under a fixed ratio 10 schedule of food presentation. Dose-effect curves were determined for positive GABAA modulators (pregnanolone, flunitrazepam, midazolam, and pentobarbital), and other drugs (ketamine and morphine) before, during, and after chronic treatment. Initially, daily pregnanolone administration increased responding; although tolerance developed to the rate-increasing effects after 14 weeks, tolerance did not develop to the rate-decreasing effects. The potencies of pregnanolone, midazolam, and morphine to decrease responding did not change during treatment, whereas flunitrazepam was more potent and pentobarbital and ketamine were less potent during treatment as compared to before treatment. Pregnanolone and midazolam were more potent after treatment than before treatment. The development of tolerance to the rate-increasing effects of pregnanolone indicates that neuroadaptations occur during chronic treatment; the fact that tolerance develops to only some effects suggests that the behavioral consequences of these neuroadaptations are limited.
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Löfgren M, Bengtsson SK, Johansson M, Bäckström T. Allopregnanolone promotes success in food competition in subordinate male rats. Neuropsychobiology 2014; 68:15-23. [PMID: 23774881 DOI: 10.1159/000350478] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 02/21/2013] [Indexed: 01/09/2023]
Abstract
BACKGROUND/AIMS Allopregnanolone or 3α-hydroxy-5α-pregnan-20-one (AlloP) is normally sedative and anxiolytic, but can under provoking circumstances paradoxically induce aggressive behavior. Therefore, it is of particular interest to determine if there is a relationship between an anxiolytic effect and aggressive behavior following AlloP administration. METHOD Male Wistar rats were housed in triads comprising of 1 young rat (35 days) and 2 older rats (55 days), with the intent of producing a social hierarchy. The triads were sampled for total serum testosterone and submitted to a social challenge in the form of a food competition test (FCT), where the rats competed for access to drinking sweetened milk. At baseline, the younger rats were identified as subordinates. To test for the behavioral effect of AlloP, the subordinate rats were given intravenous AlloP injections of 0.5 and 1 mg/kg. To assess the optimal AlloP effect, 6 intervals (5, 10, 15, 20, 30 and 40 min) between injection and the FCT were used. In separate studies, AlloP was also given by subcutaneous and intraperitoneal administration at 10 and 17 mg/kg. RESULTS AlloP (1 mg/kg, i.v.) increased drinking time and aggressive behavior in subordinate rats, with a positive correlation between these behaviors. The subcutaneous injection (17 mg/kg) also increased drinking time in subordinate animals. Serum testosterone concentration was higher in dominant compared to subordinate rats, and correlated with drinking time and weight. CONCLUSIONS AlloP increased drinking time and aggressive behavior, and the correlation indicates a relationship between an anxiolytic effect and aggressive behavior.
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Affiliation(s)
- Magnus Löfgren
- Division of Obstetrics and Gynecology, Department of Clinical Sciences, Umeå Neurosteroid Research Center, Umeå University Hospital, Umeå, Sweden.
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Irwin RW, Solinsky CM, Brinton RD. Frontiers in therapeutic development of allopregnanolone for Alzheimer's disease and other neurological disorders. Front Cell Neurosci 2014; 8:203. [PMID: 25126056 PMCID: PMC4115668 DOI: 10.3389/fncel.2014.00203] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 07/04/2014] [Indexed: 01/08/2023] Open
Abstract
Allopregnanolone (Allo), a neurosteroid, has emerged as a promising promoter of endogenous regeneration in brain. In a mouse model of Alzheimer’s disease, Allo induced neurogenesis, oligodendrogenesis, white matter generation and cholesterol homeostasis while simultaneously reducing β-amyloid and neuroinflammatory burden. Allo activates signaling pathways and gene expression required for regeneration of neural stem cells and their differentiation into neurons. In parallel, Allo activates systems to sustain cholesterol homeostasis and reduce β-amyloid generation. To advance Allo into studies for chronic human neurological conditions, we examined translational and clinical parameters: dose, regimen, route, formulation, outcome measures, and safety regulations. A treatment regimen of once per week at sub-sedative doses of Allo was optimal for regeneration and reduction in Alzheimer’s pathology. This regimen had a high safety profile following chronic exposure in aged normal and Alzheimer’s mice. Formulation of Allo for multiple routes of administration has been developed for both preclinical and clinical testing. Preclinical evidence for therapeutic efficacy of Allo spans multiple neurological diseases including Alzheimer’s, Parkinson’s, multiple sclerosis, Niemann-Pick, diabetic neuropathy, status epilepticus, and traumatic brain injury. To successfully translate Allo as a therapeutic for multiple neurological disorders, it will be necessary to tailor dose and regimen to the targeted therapeutic mechanisms and disease etiology. Treatment paradigms conducted in accelerated disease models in young animals have a low probability of successful translation to chronic diseases in adult and aged humans. Gender, genetic risks, stage and burden of disease are critical determinants of efficacy. This review focuses on recent advances in development of Allo for Alzheimer’s disease (AD) that have the potential to accelerate therapeutic translation for multiple unmet neurological needs.
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Affiliation(s)
- Ronald W Irwin
- Department of Pharmacology and Pharmaceutical Sciences, Pharmaceutical Sciences Center, School of Pharmacy, University of Southern California Los Angeles, CA, USA
| | - Christine M Solinsky
- Clinical and Experimental Therapeutics Program, School of Pharmacy, University of Southern California Los Angeles, CA, USA
| | - Roberta Diaz Brinton
- Department of Pharmacology and Pharmaceutical Sciences, Pharmaceutical Sciences Center, School of Pharmacy, University of Southern California Los Angeles, CA, USA ; Department of Neurology, Keck School of Medicine, University of Southern California Los Angeles, CA, USA
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Rabinowitz A, Cohen SJ, Finn DA, Stackman RW. The neurosteroid allopregnanolone impairs object memory and contextual fear memory in male C57BL/6J mice. Horm Behav 2014; 66:238-46. [PMID: 24874172 DOI: 10.1016/j.yhbeh.2014.05.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 05/07/2014] [Accepted: 05/15/2014] [Indexed: 12/16/2022]
Abstract
Allopregnanolone (ALLO, or 3α-hydroxy-5α-pregnan-20-one) is a steroid metabolite of progesterone and a potent endogenous positive allosteric modulator of GABA-A receptors. Systemic ALLO has been reported to impair spatial, but not nonspatial learning in the Morris water maze (MWM) and contextual memory in rodents. These cognitive effects suggest an influence of ALLO on hippocampal-dependent memory, although the specific nature of the neurosteroid's effects on learning, memory or performance is unclear. The present studies aimed to determine: (i) the memory process(es) affected by systemic ALLO using a nonspatial object memory task; and (ii) whether ALLO affects object memory via an influence within the dorsal hippocampus. Male C57BL/6J mice received systemic ALLO either before or immediately after the sample session of a novel object recognition (NOR) task. Results demonstrated that systemic ALLO impaired the encoding and consolidation of object memory. A subsequent study revealed that bilateral microinfusion of ALLO into the CA1 region of dorsal hippocampus immediately following the NOR sample session also impaired object memory consolidation. In light of debate over the hippocampal-dependence of object recognition memory, we also tested systemic ALLO-treated mice on a contextual and cued fear-conditioning task. Systemic ALLO impaired the encoding of contextual memory when administered prior to the context pre-exposure session. Together, these results indicate that ALLO exhibits primary effects on memory encoding and consolidation, and extend previous findings by demonstrating a sensitivity of nonspatial memory to ALLO, likely by disrupting dorsal hippocampal function.
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Affiliation(s)
- Akiva Rabinowitz
- Department of Psychology, Charles E. Schmidt College of Science, Florida Atlantic University, 5353 Parkside Drive, Jupiter, FL 33458, USA
| | - Sarah J Cohen
- Center for Complex Systems & Brain Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431-0991, USA
| | - Deborah A Finn
- Department of Behavioral Neuroscience, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA; Veterans Affairs Medical Center, Portland Alcohol Research Center, 3710 SW U.S. Veterans Hospital Road, Portland, OR 97239, USA
| | - Robert W Stackman
- Department of Psychology, Charles E. Schmidt College of Science, Florida Atlantic University, 5353 Parkside Drive, Jupiter, FL 33458, USA; Center for Complex Systems & Brain Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431-0991, USA.
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Irwin RW, Brinton RD. Allopregnanolone as regenerative therapeutic for Alzheimer's disease: Translational development and clinical promise. Prog Neurobiol 2014; 113:40-55. [PMID: 24044981 PMCID: PMC10124616 DOI: 10.1016/j.pneurobio.2013.08.004] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 08/22/2013] [Accepted: 08/25/2013] [Indexed: 10/26/2022]
Abstract
Herein, we review a translational development plan to advance allopregnanolone to the clinic as a regenerative therapeutic for neurodegenerative diseases, in particular Alzheimer's. Allopregnanolone, an endogenous neurosteroid that declines with age and neurodegenerative disease, was exogenously administered and assessed for safety and efficacy to promote neuro-regeneration, cognitive function and reduction of Alzheimer's pathology. Allopregnanolone-induced neurogenesis correlated with restoration of learning and memory function in a mouse model of Alzheimer's disease and was comparably efficacious in aged normal mice. Critical to success was a dosing and treatment regimen that was consistent with the temporal requirements of systems biology of regeneration in brain. A treatment regimen that adhered to regenerative requirements of brain was also efficacious in reducing Alzheimer's pathology. With an optimized dosing and treatment regimen, chronic allopregnanolone administration promoted neurogenesis, oligodendrogenesis, reduced neuroinflammation and beta-amyloid burden while increasing markers of white matter generation and cholesterol homeostasis. Allopregnanolone meets three of the four drug-like physicochemical properties described by Lipinski's rule that predict the success rate of drugs in development for clinical trials. Pharmacokinetic and pharmacodynamic outcomes, securing GMP material, development of clinically translatable formulations and acquiring regulatory approval are discussed. Investigation of allopregnanolone as a regenerative therapeutic has provided key insights into mechanistic targets for neurogenesis and disease modification, dosing requirements, optimal treatment regimen, route of administration and the appropriate formulation necessary to advance to proof of concept clinical studies to determine efficacy of allopregnanolone as a regenerative and disease modifying therapeutic for Alzheimer's disease.
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11
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Biomarkers of cognitive dysfunction in traumatic brain injury. J Neural Transm (Vienna) 2013; 121:79-90. [DOI: 10.1007/s00702-013-1078-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 07/30/2013] [Indexed: 12/11/2022]
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Alteration of neonatal Allopregnanolone levels affects exploration, anxiety, aversive learning and adult behavioural response to intrahippocampal neurosteroids. Behav Brain Res 2012; 241:96-104. [PMID: 23228522 DOI: 10.1016/j.bbr.2012.11.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 11/28/2012] [Accepted: 11/29/2012] [Indexed: 11/20/2022]
Abstract
Neurosteroids (NS) are well known to exert modulatory effects on ionotropic receptors. Recent findings indicate that NS could also act as important factors during development. In this sense, neonatal modifications of Allopregnanolone (Allop) levels during critical periods have been demonstrate to alter the morphology of the hippocampus but also other brain structures. The aim of the present work is to screen whether the alterations of Allop levels modify adult CA1 hippocampal response to NS administration. For this purpose, pups were injected with Allop (20 mg/kg s.c.), Finasteride (5α-reductase inhibitor that impedes Allop synthesis) (50 mg/kg s.c.) or Vehicle from postnatal day 5 (P5) to postnatal day 9 (P9). NS levels were tested at P5. To test the behavioural hippocampal response to NS in adulthood, animals were implanted with a bilateral cannula into the CA1 hippocampus at 80 days old and injected with Allop (0.2 μg/0.5 μl), Pregnenolone sulphate (5 ng/0.5 μl) or Vehicle in each hippocampus. After injections animals were tested in the Boisser test to assess exploratory behaviour, the elevated plus maze to assess anxiety and the passive avoidance to test aversive learning. Results indicate that alteration of neonatal Allop or pregnenolone levels (by Allop and Finasteride administration, respectively) suppressed intrahippocampal Allop anxiolytic effect in the EPM. Moreover our results also indicate that manipulation of neonatal Allop levels (Allop and Finast administration) alters exploratory and anxiety-like behaviour and impairs aversive learning in the adulthood. These data point out the role of Allop in the maturation of hippocampal function and behaviour.
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Gerak LR, France CP. Quantitative analyses of antagonism: combinations of midazolam and either flunitrazepam or pregnanolone in rhesus monkeys discriminating midazolam. J Pharmacol Exp Ther 2011; 340:742-9. [PMID: 22173893 DOI: 10.1124/jpet.111.188250] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Adverse effects of benzodiazepines limit their clinical use; these effects might be reduced without altering therapeutic effects by administering other positive GABA(A) modulators (i.e., neuroactive steroids) with benzodiazepines. One concern with this strategy involves reversing these combined effects in case of overdose. The current study examined whether flumazenil can attenuate the combined effects of two benzodiazepines, midazolam and flunitrazepam, and the combined effects of midazolam and the neuroactive steroid pregnanolone, in four monkeys discriminating midazolam. Each positive modulator produced ≥80% midazolam-lever responding. Interactions between midazolam and either flunitrazepam or pregnanolone were additive. Flumazenil antagonized the benzodiazepines when they were administered alone or in combination. Schild analyses yielded slopes that did not deviate from unity, regardless of whether benzodiazepines were administered alone or together; the pA(2) value for flumazenil was 7.58. In contrast, flumazenil enhanced the effects of pregnanolone with 0.32 mg/kg flumazenil shifting the pregnanolone dose-effect curve 2-fold leftward. Flumazenil attenuated the combined effects of midazolam and pregnanolone, although antagonism was not dose-dependent. Thus, the interaction between two benzodiazepines was similar to that of a benzodiazepine and a neuroactive steroid; however, flumazenil more efficiently attenuated a combination of two benzodiazepines compared with a combination of a benzodiazepine and a neuroactive steroid. Although the magnitude of antagonism of a benzodiazepine combined with a neuroactive steroid was reduced, these results support continued exploration of the use of combinations of positive modulators to enhance therapeutic effects while reducing adverse effects.
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Affiliation(s)
- Lisa R Gerak
- Department of Pharmacology, University of Texas Health Science Center, 7703 Floyd Curl Dr., Mail Code 7764, San Antonio, TX 78229, USA.
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Effect of acute ethanol and acute allopregnanolone on spatial memory in adolescent and adult rats. Alcohol 2011; 45:473-83. [PMID: 21600728 DOI: 10.1016/j.alcohol.2011.03.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Revised: 02/17/2011] [Accepted: 03/02/2011] [Indexed: 11/20/2022]
Abstract
The effects of ethanol differ in adolescent and adult rats on a number of measures. The evidence of the effects of ethanol on spatial memory in adolescents and adults is equivocal. Whether adolescents are more or less sensitive to ethanol-induced impairment of spatial memory acquisition remains unclear; with regard to the effects of acute ethanol on spatial memory retrieval there is almost no research looking into any age difference. Thus, we examined the effects of acute ethanol on spatial memory in the Morris Watermaze in adolescents and adults. Allopregnanolone (ALLO) is a modulator of the GABA(A) receptor and has similar behavioral effects as ethanol. We sought to also determine the effects of allopreganolone on spatial memory in adolescent and adults. Male adolescent (post natal [PN]28-30) and adult (PN70-72) rats were trained in the Morris Watermaze for 6 days and acute doses of ethanol (saline, 1.5 and 2.0 g/kg) or ALLO (vehicle, 9 and 18 mg/kg) were administered on Day 7. A probe trial followed on Day 8. As expected, there were dose effects; higher doses of both ethanol and ALLO impaired spatial memory. However, in both the ethanol and ALLO conditions adolescents and adults had similar spatial memory impairments. The current results suggest that ethanol and ALLO both impair hippocampal-dependent spatial memory regardless of age in that once learning has occurred, ethanol or ALLO does not differentially impair the retrieval of spatial memory in adolescents and adults. Given the mixed results on the effect of ethanol on cognition in adolescent rats, additional research is needed to ascertain the factors critical for the reported differential results.
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Turkmen S, Backstrom T, Wahlstrom G, Andreen L, Johansson IM. Tolerance to allopregnanolone with focus on the GABA-A receptor. Br J Pharmacol 2011; 162:311-27. [PMID: 20883478 DOI: 10.1111/j.1476-5381.2010.01059.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Many studies have suggested a relationship between stress, sex steroids, and negative mental and mood changes in humans. The progesterone metabolite allopregnanolone is a potent endogenous ligand of the γ-amino butyric acid -A (GABA-A) receptor, and the most discussed neuroactive steroid. Variations in the levels of neuroactive steroids that influence the activity of the GABA-A receptor cause a vulnerability to mental and emotional pathology. There are physiological conditions in which allopregnanolone production increases acutely (e.g. stress) or chronically (e.g. menstrual cycle, pregnancy), thus exposing the GABA-A receptor to high and continuous allopregnanolone concentrations. In such conditions, tolerance to allopregnanolone may develop. We have shown that both acute and chronic tolerances can develop to the effects of allopregnanolone. Following the development of acute allopregnanolone tolerance, there is a decrease in the abundance of the GABA-A receptor α4 subunit and the expression of the α4 subunit mRNA in the ventral-posteriomedial nucleus of the thalamus. Little is known about the mechanism behind allopregnanolone tolerance and its effects on assembly of the GABA-A receptor composition. The exact mechanism of the allopregnanolone tolerance phenomena remains unclear. The purpose of this review is to summarize certain aspects of current knowledge concerning allopregnanolone tolerance and changes in the GABA-A receptors.
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Affiliation(s)
- Sahruh Turkmen
- Department of Obstetrics & Gynaecology, Sundsvall County Hospital, Sweden.
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Comparing the discriminative stimuli produced by either the neuroactive steroid pregnanolone or the benzodiazepine midazolam in rats. Psychopharmacology (Berl) 2011; 214:427-35. [PMID: 20972551 PMCID: PMC3030657 DOI: 10.1007/s00213-010-2047-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Accepted: 10/02/2010] [Indexed: 10/18/2022]
Abstract
RATIONALE Neuroactive steroids might be therapeutic alternatives for benzodiazepines because they have similar anxiolytic, sedative, and anticonvulsant effects, and their actions at different modulatory sites on γ-aminobutyric acid(A) (GABA(A)) receptors might confer differences in adverse effects. OBJECTIVES This study used drug discrimination to compare discriminative stimuli produced by positive GABA(A) modulators that vary in their site of action on GABA(A) receptors. METHODS Two groups of rats discriminated either 3.2 mg/kg of pregnanolone or 0.56 mg/kg of midazolam from vehicle while responding under a fixed ratio 10 schedule of food presentation. RESULTS Pregnanolone, midazolam, and flunitrazepam produced ≥ 80% drug-lever responding in both groups; each drug was more potent in rats discriminating pregnanolone. Pentobarbital produced ≥ 80% drug-lever responding in all rats discriminating pregnanolone, and in 1/3 of the rats discriminating midazolam with larger doses decreasing response rates to <20% of control. Morphine and ketamine produced predominantly saline-lever responding in both groups. Flumazenil antagonized midazolam and flunitrazepam in both groups; slopes of Schild plots were not different from unity, and pA (2) values for flumazenil ranged from 5.86 to 6.09. Flumazenil did not attenuate the discriminative stimulus effects of pregnanolone. CONCLUSIONS The midazolam and pregnanolone discriminative stimuli were qualitatively similar, although the effects of pentobarbital were not identical in the two groups. Although acute effects of midazolam and pregnanolone are similar, suggesting that neuroactive steroids might retain the therapeutic effects of benzodiazepines, differences emerge during chronic treatment, indicating that neuroactive steroids might produce fewer adverse effects than benzodiazepines.
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Irwin RW, Wang JM, Chen S, Brinton RD. Neuroregenerative mechanisms of allopregnanolone in Alzheimer's disease. Front Endocrinol (Lausanne) 2011; 2:117. [PMID: 22654847 PMCID: PMC3356095 DOI: 10.3389/fendo.2011.00117] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Accepted: 12/27/2011] [Indexed: 11/25/2022] Open
Abstract
The proliferative pool and regenerative potential of neural stem cells diminishes with age, a phenomenon that may be exacerbated in prodromal and mild Alzheimer's disease (AD) brains. In parallel, the neuroactive progesterone metabolite, allopregnanolone (APα), along with a host of other factors, is decreased in the AD brain. Results of preclinical analyses demonstrate that APα is a potent inducer of neural progenitor proliferation of both rodent and human derived neural progenitor cells in vitro. In vivo, APα significantly increased neurogenesis within the subgranular zone of the dentate gyrus and subventricular zone of the 3xTgAD mouse model. Functionally, APα reversed the learning and memory deficits of 3xTgAD mice prior to and following the onset of AD pathology and was comparably efficacious in aged normal mice. In addition to inducing regenerative responses in mouse models of AD, APα significantly reduced beta-amyloid burden, beta-amyloid binding alcohol dehydrogenase load, and microglial activation. In parallel, APα increased markers of white matter generation and cholesterol homeostasis. Analyses to determine the optimal treatment regimen in the 3xTgAD mouse brain indicated that a treatment regimen of APα once per week was optimal for both inducing neurogenesis and reducing AD pathology. Pharmacokinetic analyses indicated that APα is rapidly increased in both plasma and brain following a single dose. APα is most efficacious when administered once per week which will contribute to its margin of safety. Further, analyses in both animals and humans have provided parameters for safe APα dosage exposure in humans. From a translational perspective, APα is a small molecular weight, blood brain barrier penetrant molecule with substantial preclinical efficacy data as a potential Alzheimer's therapeutic with existing safety data in animals and humans. To our knowledge, APα is the only small molecule that both promotes neural progenitor regeneration in brain and simultaneously reduces AD pathology burden.
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Affiliation(s)
- Ronald W. Irwin
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern CaliforniaLos Angeles, CA, USA
| | - Jun Ming Wang
- Department of Pathology, University of Mississippi Medical CenterJackson, MS, USA
| | - Shuhua Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern CaliforniaLos Angeles, CA, USA
| | - Roberta Diaz Brinton
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern CaliforniaLos Angeles, CA, USA
- Department of Neurology, Keck School of Medicine, University of Southern CaliforniaLos Angeles, CA, USA
- *Correspondence: Roberta Diaz Brinton, Department of Pharmacology and Pharmaceutical Sciences, Pharmaceutical Sciences Center, University of Southern California, 1985 Zonal Avenue, Los Angeles, CA 90089-9121, USA. e-mail:
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Abstract
Neurosteroids represent a class of endogenous steroids that are synthesized in the brain, the adrenals, and the gonads and have potent and selective effects on the GABAA-receptor. 3α-hydroxy A-ring reduced metabolites of progesterone, deoxycorticosterone, and testosterone are positive modulators of GABA(A)-receptor in a non-genomic manner. Allopregnanolone (3α-OH-5α-pregnan-20-one), 5α-androstane-3α, 17α-diol (Adiol), and 3α5α-tetrahydrodeoxycorticosterone (3α5α-THDOC) enhance the GABA-mediated Cl(-) currents acting on a site (or sites) distinct from the GABA, benzodiazepine, barbiturate, and picrotoxin binding sites. 3α5α-P and 3α5α-THDOC potentiate synaptic GABA(A)-receptor function and activate δ-subunit containing extrasynaptic receptors that mediate tonic currents. On the contrary, 3β-OH pregnane steroids and pregnenolone sulfate (PS) are GABA(A)-receptor antagonists and induce activation-dependent inhibition of the receptor. The activities of neurosteroid are dependent on brain regions and types of neurons. In addition to the slow genomic action of the parent steroids, the non-genomic, and rapid actions of neurosteroids play a significant role in the GABA(A)-receptor function and shift in mood and memory function. This review describes molecular mechanisms underlying neurosteroid action on the GABA(A)-receptor, mood changes, and cognitive functions.
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Affiliation(s)
- Mingde Wang
- Section of Obstetrics and Gynecology, Department of Clinical Science, Umeå Neurosteroid Research Center, Umeå UniversityUmeå, Sweden
- *Correspondence: Mingde Wang, Section of Obstetrics and Gynecology, Department of Clinical Science, Umeå Neurosteroid Research Center, Umeå University, 901 85 Umeå, Sweden. e-mail:
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Hill M, Pařízek A, Kancheva R, Jirásek JE. Reduced progesterone metabolites in human late pregnancy. Physiol Res 2010; 60:225-41. [PMID: 21114373 DOI: 10.33549/physiolres.932077] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In this review, we focused on the intersection between steroid metabolomics, obstetrics and steroid neurophysiology to give a comprehensive insight into the role of sex hormones and neuroactive steroids (NAS) in the mechanism controlling pregnancy sustaining. The data in the literature including our studies show that there is a complex mechanism providing synthesis of either pregnancy sustaining or parturition provoking steroids. This mechanism includes the boosting placental synthesis of CRH with approaching parturition inducing the excessive synthesis of 3beta-hydroxy-5-ene steroid sulfates serving primarily as precursors for placental synthesis of progestogens, estrogens and NAS. The distribution and changing activities of placental oxidoreductases are responsible for the activation or inactivation of the aforementioned steroids, which is compartment-specific (maternal and fetal compartments) and dependent on gestational age, with a tendency to shift the production from the pregnancy-sustaining steroids to the parturition provoking ones with an increasing gestational age. The fetal and maternal livers catabolize part of the bioactive steroids and also convert some precursors to bioactive steroids. Besides the progesterone, a variety of its 5alpha/beta-reduced metabolites may significantly influence the maintenance of human pregnancy, provide protection against excitotoxicity following acute hypoxic stress, and might also affect the pain perception in mother and fetus.
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Affiliation(s)
- M Hill
- Department of Obstetrics and Gynecology of the First Faculty of Medicine and General Teaching Hospital, Prague, Czech Republic.
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George O, Vallée M, Vitiello S, Le Moal M, Piazza PV, Mayo W. Low brain allopregnanolone levels mediate flattened circadian activity associated with memory impairments in aged rats. Biol Psychiatry 2010; 68:956-63. [PMID: 20471631 PMCID: PMC2936666 DOI: 10.1016/j.biopsych.2010.03.022] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 03/17/2010] [Accepted: 03/18/2010] [Indexed: 11/22/2022]
Abstract
BACKGROUND Sleep and cognitive impairments are two of the most prevalent neuropsychiatric disorders in the aged population. Age-related memory dysfunctions can result from alterations in sleep/wake circadian rhythm. However, the underlying mechanism of these alterations is unknown. Here, we demonstrate the role of alterations in brain steroid levels in age-related sleep-dependent memory impairment in rats. METHODS Sleep/wake circadian activity and spatial memory performance were evaluated in adult, middle-aged, and aged rats, and steroid levels were measured in brain structures involved in mediating sleep-dependent memory processes using gas chromatography/mass spectrometry. The causal relationship between circadian activity and allopregnanolone levels was assessed using an inhibitor of allopregnanolone synthesis (indomethacin). RESULTS Similar to observations in humans, a subpopulation of middle-aged and aged rats show flattened amplitude of circadian activity associated with impaired spatial long-term memory performance. Sleep-dependent memory dysfunction was associated with a low level of allopregnanolone in the hypothalamus, pedunculopontine nucleus, and ventral striatum. Inhibition of allopregnanolone synthesis in young rats decreased allopregnanolone in the hypothalamus and produced flattened amplitude of circadian activity similar to aged rats. CONCLUSIONS These findings identify brainstem and basal forebrain allopregnanolone as an essential endogenous substrate involved in mediating sleep-dependent memory function in young and aged rats. Allopregnanolone may play a critical role in preserving individuals from age-induced alterations in sleep and memory processes and may represent a novel target for attenuating age-related declines in sleep and memory.
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Affiliation(s)
- Olivier George
- Institut National de la Sante et de la Recherche Medical (INSERM), Unite 862, Neurocenter Magendie, Physiopathology of Addiction Group, Bordeaux, France.
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Increase of GABAA receptor-mediated tonic inhibition in dentate granule cells after traumatic brain injury. Neurobiol Dis 2010; 38:464-75. [PMID: 20304069 DOI: 10.1016/j.nbd.2010.03.012] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Revised: 03/10/2010] [Accepted: 03/10/2010] [Indexed: 10/19/2022] Open
Abstract
Traumatic brain injury (TBI) can result in altered inhibitory neurotransmission, hippocampal dysfunction, and cognitive impairments. GABAergic spontaneous and miniature inhibitory postsynaptic currents (sIPSCs and mIPSCs) and tonic (extrasynaptic) whole cell currents were recorded in control rat hippocampal dentate granule cells (DGCs) and at 90days after controlled cortical impact (CCI). At 34 degrees C, in CCI DGCs, sIPSC frequency and amplitude were unchanged, whereas mIPSC frequency was decreased (3.10+/-0.84Hz, n=16, and 2.44+/-0.67Hz, n=7, p<0.05). At 23 degrees C, 300nM diazepam increased peak amplitude of mIPSCs in control and CCI DGCs, but the increase was 20% higher in control (26.81+/-2.2pA and 42.60+/-1.22pA, n=9, p=0.031) compared to CCI DGCs (33.46+/-2.98pA and 46.13+/-1.09pA, n=10, p=0.047). At 34 degrees C, diazepam did not prolong decay time constants (6.59+/-0.12ms and 6.62+/-0.98ms, n=9, p=0.12), the latter suggesting that CCI resulted in benzodiazepine-insensitive pharmacology in synaptic GABA(A) receptors (GABA(A)Rs). In CCI DGCs, peak amplitude of mIPSCs was inhibited by 100microM furosemide (51.30+/-0.80pA at baseline and 43.50+/-5.30pA after furosemide, n=5, p<0.001), a noncompetitive antagonist of GABA(A)Rs with an enhanced affinity to alpha4 subunit-containing receptors. Potentiation of tonic current by the GABA(A)R delta subunit-preferring competitive agonist THIP (1 and 3microM) was increased in CCI DGCs (47% and 198%) compared to control DGCs (13% and 162%), suggesting the presence of larger tonic current in CCI DGCs; THIP (1microM) had no effect on mIPSCs. Taken together, these results demonstrate alterations in synaptic and extrasynaptic GABA(A)Rs in DGCs following CCI.
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Zhang H, Han T, Yu CH, Rahman K, Qin LP, Peng C. Ameliorating effects of essential oil from Acori graminei rhizoma on learning and memory in aged rats and mice. J Pharm Pharmacol 2010; 59:301-9. [PMID: 17270083 DOI: 10.1211/jpp.59.2.0016] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
Although there are normal cognitive changes that take place as a person becomes older, ageing in humans is generally associated with a deterioration of cognitive performance, in particular of learning and memory. There are a number of herbal medicines that are reported to improve brain function and intelligence. In the present study, the ameliorating effects of an essential oil extracted from Acori graminei rhizoma on learning and memory in aged, dysmnesia rats and mice were determined using the step-down passive avoidance test and Y maze. Oral administration of the essential oil (0.02, 0.04 and 0.08 g kg−1) to rats for 30 days and to mice for 15 days improved the latency and number of errors in aged, dysmnesia rats and mice. The cerebral neurotransmitters in aged rats given the essential oil (0.02, 0.04, 0.08 g kg−1) for 30 days were also investigated, and increased levels of norepinephrine, dopamine and serotonin, and decreased levels of acetylcholinesterase activity were found. The results suggest that the essential oil improves cognitive function in aged animals possibly by increasing norepinephrine, dopamine and serotonin relative levels, and by decreasing the activity of acetylcholinesterase in the cerebra.
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Affiliation(s)
- Hong Zhang
- Department of Pharmacognosy, School of Pharmacy, Second Military Medical University, Shanghai 200433, China
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23
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Hill M, Pařízek A, Velíková M, Kubátová J, Kancheva R, Dušková M, Šimůnková K, Klímková M, Pašková A, Žižka Z, Jirásek JE, Jirkovská M, Stárka L. The distribution of placental oxidoreductase isoforms provides different milieus of steroids influencing pregnancy in the maternal and fetal compartment. Horm Mol Biol Clin Investig 2010; 4:581-600. [DOI: 10.1515/hmbci.2010.077] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 11/24/2010] [Indexed: 12/27/2022]
Abstract
AbstractUsing information based on the steroid metabolome in maternal and fetal body fluids, we attempted to ascertain whether there is a common mechanism, which is based on the placental distribution of various isoforms of 17β-hydroxysteroid dehydrogenases and aldo-keto reductases. This system simultaneously provides a higher proportion of active progestogens in fetal circulation and a higher proportion of active estrogens and GABAergic steroids in the maternal compartment. The data obtained using gas chromatography-mass spectrometry completely support the aforementioned hypothesis. We confirmed a common trend to higher ratios of steroids with hydroxy-groups in the 3α-, 17β-, and 20α-positions to the corresponding 3-oxo-, 17-oxo-, and 20-oxo-metabolites, respectively, in the maternal blood when compared with the fetal circulation, and the same tendency was obvious in the 3α-hydroxy/3β-hydroxy steroid ratios. A decreasing trend was observed in the ratios of active estrogens and neuro-inhibitory steroids to their inactive counterparts in fetal and maternal body fluids. This was probably associated with a limited capacity of placental oxidoreductases in the converting of estrone to estradiol during the transplacental passage. Although we observed a decreasing trend in pregnancy-sustaining steroids with increasing gestational age, we recorded rising levels of estradiol and particularly of estriol, regardless of the limited capacity of placental oxidoreductases. Besides the estradiol, which is generally known as an active estrogen, estriol may be of importance for the termination of pregnancy with respect to its excessive concentrations near term which allows its binding to estrogen receptors.
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Martín-García E, Pallarés M. A post-training intrahippocampal anxiogenic dose of the neurosteroid pregnenolone sulfate impairs passive avoidance retention. Exp Brain Res 2008; 191:123-31. [DOI: 10.1007/s00221-008-1506-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2008] [Accepted: 07/02/2008] [Indexed: 01/04/2023]
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Türkmen S, Wahlström G, Bäckström T, Johansson IM. Persistence of tolerance to the anaesthetic effect of allopregnanolone in male rats. Eur J Pharmacol 2008; 592:73-80. [PMID: 18656468 DOI: 10.1016/j.ejphar.2008.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Revised: 06/18/2008] [Accepted: 07/01/2008] [Indexed: 11/17/2022]
Abstract
Both acute and chronic tolerance can develop to allopregnanolone-a gamma-aminobutyric acid (GABA)-modulatory progesterone metabolite. Here we investigated if acute tolerance to allopregnanolone persisted for 1 or 2 days after the induction and thus could be the initial part of chronic tolerance. Male rats were anaesthetised with allopregnanolone (i.v) to the deep anaesthesia level of the silent second (SS), which is an EEG burst suppression of 1 s or more. They were divided into four groups: SS1-anaesthesia to the first silent second; LAn (long anaesthesia)-90 min anaesthesia at the SS level; SS2;D1-90 min anaesthesia and SS induction 1 day later; SS2;D2-90 min anaesthesia and SS induction 2 days later. Allopregnanolone concentrations in tissue and serum were analysed. Levels of the GABAA receptor alpha2, alpha4, gamma2(S+L) and delta subunits mRNAs were analysed by in situ hybridisation. Acute tolerance was induced during the 90 min anaesthesia. Tolerance persisted for 1 day, since the dose of allopregnanolone needed to induce a new SS anaesthesia was increased after 1 day. The level of alpha4 subunit mRNA expression in the ventral posteriomedial nucleus of thalamus was negatively related to the tolerance parameters, the SS dose of allopregnanolone and DeltaSS (SS dose difference between days). Allopregnanolone threshold anaesthesia lasting 90 min induces acute tolerance that persisted for at least 1 day, which could be used as the start of a chronic tolerance. The alpha4 subunit may be involved in allopregnanolone caused effects in the brain.
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Affiliation(s)
- Sahruh Türkmen
- Department of Obstetrics and Gynaecology, Sundsvall County Hospital, Sundsvall, SE-851 86, Sweden.
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Brinton RD, Thompson RF, Foy MR, Baudry M, Wang J, Finch CE, Morgan TE, Pike CJ, Mack WJ, Stanczyk FZ, Nilsen J. Progesterone receptors: form and function in brain. Front Neuroendocrinol 2008; 29:313-39. [PMID: 18374402 PMCID: PMC2398769 DOI: 10.1016/j.yfrne.2008.02.001] [Citation(s) in RCA: 464] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Accepted: 02/08/2008] [Indexed: 12/13/2022]
Abstract
Emerging data indicate that progesterone has multiple non-reproductive functions in the central nervous system to regulate cognition, mood, inflammation, mitochondrial function, neurogenesis and regeneration, myelination and recovery from traumatic brain injury. Progesterone-regulated neural responses are mediated by an array of progesterone receptors (PR) that include the classic nuclear PRA and PRB receptors and splice variants of each, the seven transmembrane domain 7TMPRbeta and the membrane-associated 25-Dx PR (PGRMC1). These PRs induce classic regulation of gene expression while also transducing signaling cascades that originate at the cell membrane and ultimately activate transcription factors. Remarkably, PRs are broadly expressed throughout the brain and can be detected in every neural cell type. The distribution of PRs beyond hypothalamic borders, suggests a much broader role of progesterone in regulating neural function. Despite the large body of evidence regarding progesterone regulation of reproductive behaviors and estrogen-inducible responses as well as effects of progesterone metabolite neurosteroids, much remains to be discovered regarding the functional outcomes resulting from activation of the complex array of PRs in brain by gonadally and/or glial derived progesterone. Moreover, the impact of clinically used progestogens and developing selective PR modulators for targeted outcomes in brain is a critical avenue of investigation as the non-reproductive functions of PRs have far-reaching implications for hormone therapy to maintain neurological health and function throughout menopausal aging.
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Affiliation(s)
- Roberta Diaz Brinton
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, School of Pharmacy, 1985 Zonal Avenue, Los Angeles, CA 90089, USA.
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Russo SJ, Sun WL, Minerly ACE, Weierstall K, Nazarian A, Festa ED, Niyomchai T, Akhavan A, Luine V, Jenab S, Quiñones-Jenab V. Progesterone attenuates cocaine-induced conditioned place preference in female rats. Brain Res 2008; 1189:229-35. [DOI: 10.1016/j.brainres.2007.10.057] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2007] [Revised: 10/22/2007] [Accepted: 10/26/2007] [Indexed: 11/27/2022]
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Nyberg S, Bäckström T, Zingmark E, Purdy RH, Poromaa IS. Allopregnanolone decrease with symptom improvement during placebo and gonadotropin-releasing hormone agonist treatment in women with severe premenstrual syndrome. Gynecol Endocrinol 2007; 23:257-66. [PMID: 17558683 DOI: 10.1080/09513590701253511] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
BACKGROUND Neurosteroids such as allopregnanolone and pregnanolone are suggested to be of importance for the pathophysiology of premenstrual dysphoric disorder. The aim of this study was to investigate whether the luteal-phase serum concentrations of these neurosteroids are associated with improvement of premenstrual symptoms in 12 women with severe premenstrual syndrome after treatment with low-dose gonadotropin-releasing hormone agonist and placebo. METHODS Daily ratings for mood and physical symptoms were made prior to treatment and throughout the study. Serum progesterone, allopregnanolone and pregnanolone were assessed in the luteal phase (cycle day -9 to cycle day -1). Based on their symptom ratings, subjects were grouped as either buserelin responders (n = 6) or placebo responders (n = 6). RESULTS Buserelin responders displayed decreased levels of allopregnanolone (p < 0.05) and progesterone (p < 0.05) in parallel with improvement of symptoms. During the placebo treatment, the placebo responders had lower serum allopregnanolone concentrations than buserelin responders (p < 0.05). This was associated with improvement in symptoms compared with pre-treatment ratings. CONCLUSION Treatment response, whether induced by buserelin or placebo, appears to be associated with a decrease in allopregnanolone concentration.
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Affiliation(s)
- Sigrid Nyberg
- Department of Clinical Science, Obstetrics and Gynecology, Umeå University Hospital, Umeå, Sweden.
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Andréen L, Sundström-Poromaa I, Bixo M, Nyberg S, Bäckström T. Allopregnanolone concentration and mood--a bimodal association in postmenopausal women treated with oral progesterone. Psychopharmacology (Berl) 2006; 187:209-21. [PMID: 16724185 DOI: 10.1007/s00213-006-0417-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Accepted: 04/10/2006] [Indexed: 10/24/2022]
Abstract
RATIONALE Allopregnanolone effects on mood in postmenopausal women are unclear thus far. OBJECTIVES Allopregnanolone is a neuroactive steroid with contradictory effects. Anaesthetic, sedative, and anxiolytic as well as aggressive and anxiogenic properties have been reported. The aim of this study is to compare severity of negative mood between women receiving different serum allopregnanolone concentrations during progesterone treatment. MATERIALS AND METHODS A randomized, placebo-controlled, double-blind, crossover study of postmenopausal women (n=43) treated with 2 mg estradiol daily during four treatment cycles. Oral micronized progesterone at 30, 60, and 200 mg/day, and placebo were added sequentially to each cycle. Participants kept daily symptom ratings using a validated rating scale. Blood samples for progesterone and allopregnanolone analyses were collected during each treatment cycle. RESULTS During progesterone treatment, women had significantly higher negative mood scores when allopregnanolone serum concentration was in the range of 1.5-2 nmol/l compared to lower and higher concentrations. In addition, women displayed a significant increase in negative mood during the progesterone treatment period, compared to the estradiol-only period when 30 mg progesterone daily was used. On the other hand, treatment with higher doses of progesterone had no influence on negative mood. CONCLUSIONS Mood effects during progesterone treatment seem to be related to allopregnanolone concentration, and a bimodal association between allopregnanolone and adverse mood is evident.
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Affiliation(s)
- Lotta Andréen
- Umeå Neurosteroid Research Center, Department of Clinical Science, Obstetrics and Gynecology, Norrlands University Hospital, SE-901 85, Umeå, Sweden
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