1
|
Ampuero E, Luarte A, Flores FS, Soto AI, Pino C, Silva V, Erlandsen M, Concha T, Wyneken U. The multifaceted effects of fluoxetine treatment on cognitive functions. Front Pharmacol 2024; 15:1412420. [PMID: 39081952 PMCID: PMC11286485 DOI: 10.3389/fphar.2024.1412420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 06/10/2024] [Indexed: 08/02/2024] Open
Abstract
Fluoxetine, the prototypical selective serotonin reuptake inhibitor (SSRI), is widely used to treat major depressive disorder (MDD) and a variety of other central nervous system conditions, primarily due to its established clinical safety profile. Although its efficacy in treating depression is well-recognized, the impact of fluoxetine on cognitive functions remains inconsistent and elusive. In this review, we first examine the well-substantiated biological mechanisms underlying fluoxetine's antidepressant effects, which include serotonin reuptake inhibition and activation of TrkB receptors-key to brain-derived neurotrophic factor (BDNF) signaling. Subsequently, we delve into the cognitive side effects observed in both preclinical and clinical studies, affecting domains such as memory, attention, and executive functions. While certain studies indicate cognitive improvements in patients with underlying disorders, there is also evidence of negative effects, influenced by variables like gender, duration of treatment, age, disease pathology, and the specifics of cognitive testing. Significantly, the negative cognitive outcomes reported in preclinical research often involve healthy, non-diseased animals. This review underscores the necessity for heightened caution in fluoxetine prescription and further investigation into its potentially detrimental cognitive effects, even when used prophylactically.
Collapse
Affiliation(s)
- Estíbaliz Ampuero
- Laboratorio Neurofarmacología del Comportamiento, Facultad de Química y Biología, Universidad de Santiago, Santiago, Chile
| | - Alejandro Luarte
- Laboratorio Neurociencias, Facultad de Medicina, Universidad de los Andes, Santiago, Chile
| | - Francisca Sofia Flores
- Laboratorio Neurociencias, Facultad de Medicina, Universidad de los Andes, Santiago, Chile
| | - Antonia Ignacia Soto
- Laboratorio Neurociencias, Facultad de Medicina, Universidad de los Andes, Santiago, Chile
| | - Catalina Pino
- Laboratorio Neurociencias, Facultad de Medicina, Universidad de los Andes, Santiago, Chile
| | - Viviana Silva
- Laboratorio Neurociencias, Facultad de Medicina, Universidad de los Andes, Santiago, Chile
| | - Macarena Erlandsen
- Laboratorio Neurociencias, Facultad de Medicina, Universidad de los Andes, Santiago, Chile
| | - Teresita Concha
- Laboratorio Neurociencias, Facultad de Medicina, Universidad de los Andes, Santiago, Chile
| | - Ursula Wyneken
- Laboratorio Neurociencias, Facultad de Medicina, Universidad de los Andes, Santiago, Chile
- IMPACT, Center of Interventional Medicine for Precision and Advanced Cellular Therapy, Santiago, Chile
| |
Collapse
|
2
|
Grosu ȘA, Chirilă M, Rad F, Enache A, Handra CM, Ghiță I. The Effects of Four Compounds That Act on the Dopaminergic and Serotonergic Systems on Working Memory in Animal Studies; A Literature Review. Brain Sci 2023; 13:brainsci13040546. [PMID: 37190512 DOI: 10.3390/brainsci13040546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/23/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
The dopaminergic and serotonergic systems are two of the most important neuronal pathways in the human brain. Almost all psychotropic medications impact at least one neurotransmitter system. As a result, investigating how they affect memory could yield valuable insights into potential therapeutic applications or unanticipated side effects. The aim of this literature review was to collect literature data from animal studies regarding the effects on memory of four drugs known to act on the serotonergic and dopaminergic systems. The studies included in this review were identified in the PubMed database using selection criteria from the PRISMA protocol. We analyzed 29 articles investigating one of four different dopaminergic or serotonergic compounds. Studies conducted on bromocriptine have shown that stimulating D2 receptors may enhance working memory in rodents, whereas inhibiting these receptors could have the opposite effect, reducing working memory performance. The effects of serotonin on working memory are not clearly established as studies on fluoxetine and ketanserin have yielded conflicting results. Further studies with better-designed methodologies are necessary to explore the impact of compounds that affect both the dopaminergic and serotonergic systems on working memory.
Collapse
|
3
|
Gerace E, Polenzani L, Magnani M, Zianni E, Stocca G, Gardoni F, Pellegrini-Giampietro DE, Corradetti R. Antidepressant-induced increase in GluA2 expression does not translate in changes of AMPA receptor-mediated synaptic transmission at CA3/CA1 synapses in rats. Neuropharmacology 2023; 223:109307. [PMID: 36334766 DOI: 10.1016/j.neuropharm.2022.109307] [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: 08/07/2022] [Revised: 10/14/2022] [Accepted: 10/23/2022] [Indexed: 11/06/2022]
Abstract
Chronic treatment with serotonin selective reuptake inhibitors or tryciclic antidepressant drugs in rodents has been shown to increase the expression of GluA1 and/or GluA2 AMPA receptor (AMPAR) subunits in several brain areas, including the hippocampus. These changes in AMPAR composition have been suggested to result in increased glutamatergic neurotransmission and possibly underlie enhanced hippocampal synaptic plasticity through the increased availability of calcium-permeable AMPARs, specifically at CA3/CA1 synapses. However, the possibility that chronic treatment with antidepressants actually results in strengthened glutamatergic neurotransmission in CA1 has poorly been investigated. Here, we studied whether chronic treatment with the multimodal antidepressant drug trazodone mimicked the effect of paroxetine on the expression of AMPAR subunits in male wistar rat hippocampus and whether these drugs produced a parallel facilitation of field excitatory postsynaptic potentials (fEPSP) responses evoked by activation of CA3/CA1 synapses in dorsal hippocampal slices. In addition, we investigated whether the quality of glutamatergic AMPARs involved in basal neurotransmission was changed by altered subunit expression, e.g. leading to appearance of calcium-permeable AMPARs. We found a significant increase in GluA2 subunit expression following treatment with trazodone or paroxetine for twenty-one days, but not after seven-days treatment. In contrast, we did not find any significant changes in fEPSP responses supporting either a facilitation of glutamatergic neurotransmission in basal conditions or the appearance of functional calcium-permeable AMPARs at CA3/CA1 pyramidal neuron synapses. Thus, neurochemically-detected increases in the expression of AMPAR subunits cannot directly be extrapolated in increased number of functioning receptors and/or facilitated basal neurotransmission.
Collapse
Affiliation(s)
- Elisabetta Gerace
- Department of NEUROFARBA, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy; Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy.
| | | | | | - Elisa Zianni
- Department of Pharmacological and Biomolecular Sciences (DiSFeB), University of Milan, Milan, Italy
| | - Gabriella Stocca
- Department of NEUROFARBA, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy
| | - Fabrizio Gardoni
- Department of Pharmacological and Biomolecular Sciences (DiSFeB), University of Milan, Milan, Italy
| | | | - Renato Corradetti
- Department of NEUROFARBA, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy
| |
Collapse
|
4
|
Atef RM, Abdel Fattah IO, Mahmoud OM, Abdel-Rahman GM, Salem NA. Protective effects of Rosemary extract and/or Fluoxetine on Monosodium Glutamate-induced hippocampal neurotoxicity in rat. ROMANIAN JOURNAL OF MORPHOLOGY AND EMBRYOLOGY 2021; 62:169-177. [PMID: 34609419 PMCID: PMC8597363 DOI: 10.47162/rjme.62.1.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The use of Monosodium Glutamate (MSG) as a food flavor enhancer is increasing worldwide despite its neurotoxic effects. Fluoxetine (FLX) and Rosemary extract (RE) are known to have beneficial neuroprotective properties. Rats were divided into five groups: control group; MSG group, rats received 2 g/kg/day intraperitoneal (i.p.) injections of MSG for seven days; RE/MSG group, rats received 50 mg/kg/day of oral RE for 28 days starting prior to MSG; FLX/MSG group, rats received 10 mg/kg/day of oral FLX for 28 days beginning before MSG; and RE/FLX/MSG group, received combined treatments as mentioned above. Rats underwent the Barnes maze test, in addition to histopathological, immunohistochemical, morphometric and ultrastructural evaluations for their hippocampi. MSG increased the number of errors and escaped latency in the Barnes maze test that was significantly minimized in the three treatment groups. The MSG group exhibited pyramidal cell (PC) degeneration, shrunken glial cells and massive vascular dilatation that were improved with RE and/or FLX treatment. The number of glial fibrillary acidic protein (GFAP)-immunopositive cells were increased, and the number of PCs was decreased in the MSG group, while these values were significantly reversed with the three treatment groups with the most significant improvement at RE/FLX/MSG one. Ultrastructurally, PCs were shrunken with degenerated nuclei, dilated endoplasmic reticulum, swollen mitochondria, and vacuolations in the MSG group that were improved with RE and/or FLX. In conclusion, the combined RE and FLX treatment can ameliorate the toxic effect of MSG on rat hippocampus probably through its antioxidant and anti-inflammatory effects.
Collapse
Affiliation(s)
- Reham Mohammed Atef
- Department of Human Anatomy and Embryology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt;
| | | | | | | | | |
Collapse
|
5
|
Phospholipase Cβ3 in the hippocampus may mediate impairment of memory by long-term blockade of orexin 1 receptors assessed by the Morris water maze. Life Sci 2020; 257:118046. [PMID: 32622948 DOI: 10.1016/j.lfs.2020.118046] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/19/2020] [Accepted: 06/30/2020] [Indexed: 11/23/2022]
Abstract
Orexin-A is an endogenous peptide with receptors throughout the brain. According to some recent research, learning and memory are affected by the central administration of orexin; however, no study so far has investigated the long-term inhibition of the orexinergic system. The present study has evaluated the effect of pretraining administration of orexin 1 receptor (OXR1) antagonist, SB-334867, on the acquisition of memory. The Morris water maze (MWM) task was used for training and trial purposes in all groups. Memory performance was analyzed by measuring escape latency, traveled distance, and time spent in the target quadrant. Moreover, the effect of SB-334867 on phospholipase Cβ3 (PLCβ3) levels in the CA1 region of hippocampus slices was examined. Hippocampus slices were prepared using an immunohistochemistry (IHC) approach. SB-334867 (20 mg/kg) increased escape latency in SB-treated rats compared to SB-vehicle group (P < 0.01). SB-treated rats spent less time in the target quadrant compared to the SB-vehicle group (P < 0.001). Distance traveled in the target quadrant was significantly more in SB-treated rats compared to the SB-vehicle group (P < 0.001). Furthermore, SB-334867 decreased PLCβ3 levels in the CA1 of the hippocampus (P < 0.01 and P < 0.05, respectively). Put together, our results suggest that the long-term inhibition of OXR1 plays a prominent role in spatial learning and memory, probably by attenuating PLCβ3 in CA1 neurons.
Collapse
|
6
|
Chen Y, Li S, Zhong X, Kang Z, Chen R. PDE-7 Inhibitor BRL-50481 Reduces Neurodegeneration and Long-Term Memory Deficits in Mice Following Sevoflurane Exposure. ACS Chem Neurosci 2020; 11:1353-1358. [PMID: 32271540 DOI: 10.1021/acschemneuro.0c00106] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Sevoflurane, one of the most commonly used anesthetic agents, has been demonstrated to induce widespread neurodegeneration in the developing brain. We aimed to evaluate the protective effects of a PDE-7 inhibitor (BRL-50481) against the neurotoxic effects of sevoflurane on the developing nervous system. Spatial learning and memory in sevoflurane-treated mice were examined using the Morris water maze test, and neuroprotective effects of PDE-7 inhibitor (BRL-50481) against sevoflurane-induced impairments were evaluated. Our results showed that sevoflurane treatment markedly induced neurodegeneration and impaired long-term memory in neonatal mice. Notably, BRL-50481 coadministration could significantly attenuate sevoflurane-induced learning and memory defects, prevent deterioration of recognition memory, and protect against neuron apoptosis. Mechanistically, BRL-50481 administration suppressed sevoflurane-induced neurodegenerative disorders through restoring cAMP and activating cAMP/CREB signaling in the hippocampus. PDE7 inhibitor may be a potential therapeutic agent for sevoflurane-induced neurodegeneration and long-term memory deficits.
Collapse
Affiliation(s)
- Yingle Chen
- Department of Anesthesiology, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou 362000, Fujian, China
| | - Shunyuan Li
- Department of Anesthesiology, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou 362000, Fujian, China
| | - Xianmei Zhong
- Department of Anesthesiology, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou 362000, Fujian, China
| | - Zhenming Kang
- Department of Anesthesiology, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou 362000, Fujian, China
| | - Rulei Chen
- Department of Anesthesiology, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou 362000, Fujian, China
| |
Collapse
|
7
|
Zhao Z, Li B, Wu Y, Chen X, Guo Y, Shen Y, Huang H. Ketamine affects the integration of developmentally generated granule neurons in the adult stage. BMC Neurosci 2019; 20:60. [PMID: 31852437 PMCID: PMC6921590 DOI: 10.1186/s12868-019-0542-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 12/07/2019] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Ketamine has been reported to cause neonatal neurotoxicity in a variety of developing animal models. Various studies have been conducted to study the mechanism of neurotoxicity for general anesthetic use during the neonatal period. Previous experiments have suggested that developmentally generated granule neurons in the hippocampus dentate gyrus (DG) supported hippocampus-dependent memory. Therefore, this study aimed to investigate whether ketamine affects the functional integration of developmentally generated granule neurons in the DG. For this purpose,the postnatal day 7 (PND-7) Sprague-Dawley (SD) rats were divided into the control group and the ketamine group (rats who received 4 injections of 40 mg/kg ketamine at 1 h intervals). To label dividing cells, BrdU was administered for three consecutive days after the ketamine exposure; NeuN+/BrdU+cells were observed by using immunofluorescence. To evaluate the developmentally generated granule neurons that support hippocampus-dependent memory, spatial reference memory was tested by using Morris Water Maze at 3 months old, after which the immunofluorescence was used to detect c-Fos expression in the NeuN+/BrdU+ cells. The expression of caspase-3 was measured by western blot to detect the apoptosis in the hippocampal DG. RESULTS The present results showed that the neonatal ketamine exposure did not influence the survival rate of developmentally generated granule neurons at 2 and 3 months old, but ketamine interfered with the integration of these neurons into the hippocampal DG neural circuits and caused a deficit in hippocampal-dependent spatial reference memory tasks. CONCLUSIONS In summary, these findings may promote more studies to investigate the neurotoxicity of ketamine in the developing brain.
Collapse
Affiliation(s)
- Zhanqiang Zhao
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Bing Li
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Yuqing Wu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou, China
| | - Xujun Chen
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Yan Guo
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Yang Shen
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - He Huang
- Department of Anesthesiology, First Affiliated Hospital With Nanjing Medical University, Guangzhou Road 300, Nanjing, 210029, Jiangsu, People's Republic of China.
| |
Collapse
|
8
|
Depression and adult neurogenesis: Positive effects of the antidepressant fluoxetine and of physical exercise. Brain Res Bull 2018; 143:181-193. [PMID: 30236533 DOI: 10.1016/j.brainresbull.2018.09.002] [Citation(s) in RCA: 167] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/03/2018] [Accepted: 09/11/2018] [Indexed: 12/11/2022]
Abstract
Of wide interest for health is the relation existing between depression, a very common psychological illness, accompanied by anxiety and reduced ability to concentrate, and adult neurogenesis. We will focus on two neurogenic stimuli, fluoxetine and physical exercise, both endowed with the ability to activate adult neurogenesis in the dentate gyrus of the hippocampus, known to be required for learning and memory, and both able to counteract depression. Fluoxetine belongs to the class of selective serotonin reuptake inhibitor (SSRI) antidepressants, which represent the most used pharmacological therapy; physical exercise has also been shown to effectively counteract depression symptoms in rodents as well as in humans. While there is evidence that the antidepressant effect of fluoxetine requires its pro-neurogenic action, exerted by promoting proliferation, differentiation and survival of progenitor cells of the hippocampus, on the other hand fluoxetine exerts also neurogenesis-independent antidepressant effects by influencing the plasticity of the new neurons generated. Similarly, the antidepressant action of running also correlates with an increase of hippocampal neurogenesis and plasticity, although the gene pathways involved are only partially coincident with those of fluoxetine, such as those involved in serotonin metabolism and synapse formation. We further discuss how extra-neurogenic actions are also suggested by the fact that, unlike running, fluoxetine is unable to stimulate neurogenesis during aging, but still displays antidepressant effects. Moreover, in specific conditions, fluoxetine or running activate not only progenitor but also stem cells, which normally are not stimulated; this fact reveals how stem cells have a long-term, hidden ability to self-renew and, more generally, that neurogenesis is subject to complex controls that may play a role in depression, such as the type of neurogenic stimulus or the state of the local niche. Finally, we discuss how fluoxetine or running are effective in counteracting depression originated from stress or neurodegenerative diseases.
Collapse
|
9
|
Jo SY, Jung IH, Yi JH, Choi TJ, Lee S, Jung JW, Yun J, Lee YC, Ryu JH, Kim DH. Ethanol extract of the seed of Zizyphus jujuba var. spinosa potentiates hippocampal synaptic transmission through mitogen-activated protein kinase, adenylyl cyclase, and protein kinase A pathways. JOURNAL OF ETHNOPHARMACOLOGY 2017; 200:16-21. [PMID: 28167293 DOI: 10.1016/j.jep.2017.02.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 01/20/2017] [Accepted: 02/03/2017] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE As the seed of Zizyphus jujuba var. spinosa (Bunge) Hu ex H.F. Chow (Rhamnaceae) has been used to sleep disturbances in traditional Chinese and Korean medicine, many previous studies have focused on its sedative effect. AIM OF THE STUDY Recently, we reported the neuroprotective effect of the effect of Z. jujuba var. spinosa. However, its effects on synaptic function have not yet been studied. In this project, we examined the action of ethanol extract of the seed of Z. jujuba var. spinosa (DHP1401) on synaptic transmission in the hippocampus. MATERIALS AND METHODS To investigate the effects of DHP1401, field recordings were conducted using hippocampal slices (400µm). Object recognition test was introduced to examine whether DHP1401 affect normal recognition memory. RESULTS DHP1401 (50μg/ml) induced a significant increase in synaptic activity in Shaffer collateral pathway in a concentration-dependent manner. This increase of synaptic responses was blocked by NBQX, a broad spectrum α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist, but not IEM-1460, a Ca2+-permeable AMPAR blocker. Moreover, U0126, a mitogen-activated protein kinase inhibitor, SQ22536, an adenylyl cyclase inhibitor, and PKI, a protein kinase A inhibitor, blocked DHP1401-induced increase in synaptic transmission. Finally, DHP1401 facilitated object recognition memory. CONCLUSIONS These results suggest that DHP1401 increase synaptic transmission through increase of synaptic AMPAR transmission via MAPK, AC and PAK.
Collapse
Affiliation(s)
- So Yeon Jo
- Department of Biotechnology, College of Natural Resources and Life Science, Dong-A University, Busan 49315, Republic of Korea.
| | - In Ho Jung
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Hoeki-dong, Dongdaemoon-Ku, Seoul 02447, Republic of Korea; Daehwa Pharmaceutical Co., Ltd., Seongnam 13488, Republic of Korea.
| | - Jee Hyun Yi
- School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Bristol, UK.
| | - Tae Joon Choi
- Daehwa Pharmaceutical Co., Ltd., Seongnam 13488, Republic of Korea.
| | - Seungheon Lee
- Department of Aquatic Biomedical Sciences, School of Marine Biomedical Science, College of Ocean Science, Jeju National University, Jeju 63243, Republic of Korea.
| | - Ji Wook Jung
- Department of Herbal Medicinal Pharmacology, College of Herbal Bio-industry, Daegu Haany University, Kyungsan 38610, Republic of Korea.
| | - Jeanho Yun
- Department of Biochemistry, College of Medicine, Dong-A University, Busan 607-714, Republic of Korea; Institute of Convergence Bio-Health, Dong-A University, Busan 49315, Republic of Korea.
| | - Young Choon Lee
- Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan 49315, Republic of Korea; Institute of Convergence Bio-Health, Dong-A University, Busan 49315, Republic of Korea.
| | - Jong Hoon Ryu
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Hoeki-dong, Dongdaemoon-Ku, Seoul 02447, Republic of Korea; Department of Oriental Pharmaceutical Science, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea; Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea.
| | - Dong Hyun Kim
- Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan 49315, Republic of Korea; Institute of Convergence Bio-Health, Dong-A University, Busan 49315, Republic of Korea.
| |
Collapse
|
10
|
Huang H, Liu CM, Sun J, Hao T, Xu CM, Wang D, Wu YQ. Ketamine Affects the Neurogenesis of the Hippocampal Dentate Gyrus in 7-Day-Old Rats. Neurotox Res 2016; 30:185-98. [PMID: 26966008 DOI: 10.1007/s12640-016-9615-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 02/22/2016] [Accepted: 03/01/2016] [Indexed: 01/20/2023]
Abstract
Ketamine has been reported to cause neonatal neurotoxicity via a neuronal apoptosis mechanism; however, no in vivo research has reported whether ketamine could affect postnatal neurogenesis in the hippocampal dentate gyrus (DG). A growing number of experiments suggest that postnatal hippocampal neurogenesis is the foundation of maintaining normal hippocampus function into adulthood. Therefore, this study investigated the effect of ketamine on hippocampal neurogenesis. Male Sprague-Dawley rats were divided into two groups: the control group (equal volume of normal saline), and the ketamine-anesthesia group (40 mg/kg ketamine in four injections at 1 h intervals). The S-phase marker 5-bromodeoxyuridine (BrdU) was administered after ketamine exposure to postnatal day 7 (PND-7) rats, and the neurogenesis in the hippocampal DG was assessed using single- or double-immunofluorescence staining. The expression of GFAP in the hippocampal DG was measured by western blot analysis. Spatial reference memory was tested by Morris water maze at 2 months after PND-7 rats exposed to ketamine treatment. The present results showed that neonatal ketamine exposure significantly inhibited neural stem cell (NSC) proliferation, decreased astrocytic differentiation, and markedly enhanced neuronal differentiation. The disruptive effect of ketamine on the proliferation and differentiation of NSCs lasted at least 1 week and disappeared by 2 weeks after ketamine exposure. Moreover, the migration of newborn neurons in the granule cell layer and the growth of astrocytes in the hippocampal DG were inhibited by ketamine on PND-37 and PND-44. Finally, ketamine caused a deficit in hippocampal-dependent spatial reference memory tasks at 2 months old. Our results suggested that ketamine may interfere with hippocampal neurogenesis and long-term neurocognitive function in PND-7 rats. These findings may provide a new perspective to explain the adult neurocognitive dysfunction induced by neonatal ketamine exposure.
Collapse
Affiliation(s)
- He Huang
- Department of Anesthesiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Cun-Ming Liu
- Department of Anesthesiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jie Sun
- Department of Anesthesiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ting Hao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, China
| | - Chun-Mei Xu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, China
| | - Dan Wang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, China
| | - Yu-Qing Wu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, China.
| |
Collapse
|
11
|
Epp JR, Silva Mera R, Köhler S, Josselyn SA, Frankland PW. Neurogenesis-mediated forgetting minimizes proactive interference. Nat Commun 2016; 7:10838. [PMID: 26917323 PMCID: PMC4773435 DOI: 10.1038/ncomms10838] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 01/26/2016] [Indexed: 12/30/2022] Open
Abstract
Established memories may interfere with the encoding of new memories, particularly when existing and new memories overlap in content. By manipulating levels of hippocampal neurogenesis, here we show that neurogenesis regulates this form of proactive interference. Increasing hippocampal neurogenesis weakens existing memories and, in doing so, facilitates the encoding of new, conflicting (but not non-conflicting) information in mice. Conversely, decreasing neurogenesis stabilizes existing memories, and impedes the encoding of new, conflicting information. These results suggest that reduced proactive interference is an adaptive benefit of neurogenesis-induced forgetting. New neurons are continuously produced throughout adulthood in the hippocampus. Here the authors provide evidence that adult hippocampal neurogenesis weakens existing memories, and facilitates the encoding of new, confliction information in mice.
Collapse
Affiliation(s)
- Jonathan R Epp
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada M5G 1X8
| | - Rudy Silva Mera
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada M5G 1X8
| | - Stefan Köhler
- Department of Psychology, Brain and Mind Institute, University of Western Ontario, London, Ontario, Canada N6A 5B7.,Baycrest Centre, Rotman Research Institute, Toronto, Ontario, Canada M6A 2E1
| | - Sheena A Josselyn
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada M5G 1X8.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada M5S 3GM.,Department of Physiology, University of Toronto, Toronto, Ontario, Canada M5S 1A8.,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Paul W Frankland
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada M5G 1X8.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada M5S 3GM.,Department of Physiology, University of Toronto, Toronto, Ontario, Canada M5S 1A8.,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| |
Collapse
|
12
|
Barha CK, Lieblich SE, Chow C, Galea LAM. Multiparity-induced enhancement of hippocampal neurogenesis and spatial memory depends on ovarian hormone status in middle age. Neurobiol Aging 2015; 36:2391-405. [PMID: 25998101 DOI: 10.1016/j.neurobiolaging.2015.04.007] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 04/16/2015] [Accepted: 04/17/2015] [Indexed: 12/13/2022]
Abstract
Menopause is associated with cognitive decline, and previous parity can increase or delay the trajectory of cognitive aging. Furthermore, parity enables the hippocampus to respond to estrogens in middle age. The present study investigated how previous parity and estrogens influence cognition, neurogenesis, and neuronal activation in response to memory retrieval in the hippocampus of middle-aged females. Multiparous and nulliparous rats were ovariectomized (OVX) or received sham surgery and were treated with vehicle, 17β-estradiol, 17α-estradiol, or estrone. Rats were trained on the spatial working and reference memory versions of the Morris water maze. Multiparous rats had a significantly greater density of immature neurons in the hippocampus, enhanced acquisition of working memory, but poorer reference memory compared with nulliparous rats. Furthermore, OVX increased, while treatment with estrogens reduced, the density of immature neurons, regardless of parity. OVX improved reference memory only in nulliparous rats. Thus, motherhood has long-lasting effects on the neuroplasticity and function of the hippocampus. These findings have wide-ranging implications for the treatment of age-associated decline in women.
Collapse
Affiliation(s)
- Cindy K Barha
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephanie E Lieblich
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Carmen Chow
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Liisa A M Galea
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada; Graduate Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada; Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.
| |
Collapse
|
13
|
Stratmann G, Sall JW, May LDV, Loepke AW, Lee MT. Beyond anesthetic properties: the effects of isoflurane on brain cell death, neurogenesis, and long-term neurocognitive function. Anesth Analg 2014; 110:431-7. [PMID: 19917621 DOI: 10.1213/ane.0b013e3181af8015] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Anesthetic drugs cause brain cell death and long-term neurocognitive dysfunction in neonatal rats. Recently, human data also suggest that anesthesia early in life may cause cognitive impairment. The connection between cell death and neurocognitive decline is uncertain. It is conceivable that mechanisms other than brain cell death contribute to neurocognitive outcome of neonatal anesthesia. In a series of experiments, we demonstrate that isoflurane exposure causes significant hypercarbia in postnatal day 7 rats and that exposure to isoflurane or carbon dioxide for 4 h provoked brain cell death. However, 1 h of isoflurane exposure was not sufficient to cause brain cell death. Moreover, only 4 h of isoflurane exposure, but not 1 or 2 h of exposure or 4 h of carbon dioxide, led to impaired hippocampal function,questioning the association between anesthesia-induced brain cell death and neurocognitive dysfunction. Neurogenesis both in the developing and adult dentate gyrus is important for hippocampal function, specifically learning and memory. γ-Amino-butyric-acid regulates proliferation and neuronal differentiation both in the developing and the adult brain. Inhaled anesthetics are γ-amino-butyric-acid-ergic and may therefore affect neurogenesis, which could be an alternative mechanism mediating anesthesia-induced neurocognitive decline in immature rats. Understanding the mechanism will help guide clinical trials aiming to define the scope of the problem in humans and may lead to preventive and therapeutic strategies.
Collapse
Affiliation(s)
- Greg Stratmann
- Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, California, USA.
| | | | | | | | | |
Collapse
|
14
|
Dringenberg HC, Branfield Day LR, Choi DH. Chronic fluoxetine treatment suppresses plasticity (long-term potentiation) in the mature rodent primary auditory cortex in vivo. Neural Plast 2014; 2014:571285. [PMID: 24719772 PMCID: PMC3956292 DOI: 10.1155/2014/571285] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/12/2014] [Accepted: 01/13/2014] [Indexed: 01/13/2023] Open
Abstract
Several recent studies have provided evidence that chronic treatment with the selective serotonin reuptake inhibitor (SSRI) fluoxetine can facilitate synaptic plasticity (e.g., ocular dominance shifts) in the adult central nervous system. Here, we assessed whether fluoxetine enhances long-term potentiation (LTP) in the thalamocortical auditory system of mature rats, a developmentally regulated form of plasticity that shows a characteristic decline during postnatal life. Adult rats were chronically treated with fluoxetine (administered in the drinking water, 0.2 mg/mL, four weeks of treatment). Electrophysiological assessments were conducted using an anesthetized (urethane) in vivo preparation, with LTP of field potentials in the primary auditory cortex (A1) induced by theta-burst stimulation of the medial geniculate nucleus. We find that, compared to water-treated control animals, fluoxetine-treated rats did not express higher levels of LTP and, in fact, exhibited reduced levels of potentiation at presumed intracortical A1 synapses. Bioactivity of fluoxetine was confirmed by a reduction of weight gain and fluid intake during the four-week treatment period. We conclude that chronic fluoxetine treatment fails to enhance LTP in the mature rodent thalamocortical auditory system, results that bring into question the notion that SSRIs act as general facilitators of synaptic plasticity in the mammalian forebrain.
Collapse
Affiliation(s)
- Hans C. Dringenberg
- Department of Psychology, Queen's University, Kingston, ON, Canada K7L 3N6
- Center for Neuroscience Studies, Queen's University, Kingston, ON, Canada K7L 3N6
| | | | - Deanna H. Choi
- Department of Psychology, Queen's University, Kingston, ON, Canada K7L 3N6
| |
Collapse
|
15
|
Pavlopoulos E, Jones S, Kosmidis S, Close M, Kim C, Kovalerchik O, Small SA, Kandel ER. Molecular mechanism for age-related memory loss: the histone-binding protein RbAp48. Sci Transl Med 2013; 5:200ra115. [PMID: 23986399 PMCID: PMC4940031 DOI: 10.1126/scitranslmed.3006373] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
To distinguish age-related memory loss more explicitly from Alzheimer's disease (AD), we have explored its molecular underpinning in the dentate gyrus (DG), a subregion of the hippocampal formation thought to be targeted by aging. We carried out a gene expression study in human postmortem tissue harvested from both DG and entorhinal cortex (EC), a neighboring subregion unaffected by aging and known to be the site of onset of AD. Using expression in the EC for normalization, we identified 17 genes that manifested reliable age-related changes in the DG. The most significant change was an age-related decline in RbAp48, a histone-binding protein that modifies histone acetylation. To test whether the RbAp48 decline could be responsible for age-related memory loss, we turned to mice and found that, consistent with humans, RbAp48 was less abundant in the DG of old than in young mice. We next generated a transgenic mouse that expressed a dominant-negative inhibitor of RbAp48 in the adult forebrain. Inhibition of RbAp48 in young mice caused hippocampus-dependent memory deficits similar to those associated with aging, as measured by novel object recognition and Morris water maze tests. Functional magnetic resonance imaging studies showed that within the hippocampal formation, dysfunction was selectively observed in the DG, and this corresponded to a regionally selective decrease in histone acetylation. Up-regulation of RbAp48 in the DG of aged wild-type mice ameliorated age-related hippocampus-based memory loss and age-related abnormalities in histone acetylation. Together, these findings show that the DG is a hippocampal subregion targeted by aging, and identify molecular mechanisms of cognitive aging that could serve as valid targets for therapeutic intervention.
Collapse
Affiliation(s)
- Elias Pavlopoulos
- Department of Neuroscience, Columbia University, New York, NY 10032, USA
- Kavli Institute for Brain Science, Columbia University, New York, NY 10032, USA
- Howard Hughes Medical Institute, Columbia University, New York, NY 10032, USA
| | - Sidonie Jones
- Department of Neurology, Columbia University, New York, NY 10032, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY 10032, USA
| | - Stylianos Kosmidis
- Department of Neuroscience, Columbia University, New York, NY 10032, USA
- Kavli Institute for Brain Science, Columbia University, New York, NY 10032, USA
- Howard Hughes Medical Institute, Columbia University, New York, NY 10032, USA
| | - Maggie Close
- Department of Neuroscience, Columbia University, New York, NY 10032, USA
| | - Carla Kim
- Department of Neuroscience, Columbia University, New York, NY 10032, USA
| | - Olga Kovalerchik
- Department of Neuroscience, Columbia University, New York, NY 10032, USA
| | - Scott A. Small
- Department of Neurology, Columbia University, New York, NY 10032, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY 10032, USA
| | - Eric R. Kandel
- Department of Neuroscience, Columbia University, New York, NY 10032, USA
- Kavli Institute for Brain Science, Columbia University, New York, NY 10032, USA
- Howard Hughes Medical Institute, Columbia University, New York, NY 10032, USA
| |
Collapse
|
16
|
Fang F, Xue Z, Cang J. Sevoflurane exposure in 7-day-old rats affects neurogenesis, neurodegeneration and neurocognitive function. Neurosci Bull 2012; 28:499-508. [PMID: 22965743 DOI: 10.1007/s12264-012-1260-4] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 02/15/2012] [Indexed: 10/27/2022] Open
Abstract
OBJECTIVE Sevoflurane is widely used in pediatric anesthesia and former studies showed that it causes neurodegeneration in the developing brain. The present study was carried out to investigate the effects of sevoflurane on neurogenesis, neurodegeneration and behavior. METHODS We administered 5-bromodeoxyuridine, an S-phase marker, before, during, and after 4 h of sevoflurane given to rats on postnatal day 7 to assess dentate gyrus progenitor proliferation and Fluoro-Jade staining for degeneration. Spatial reference memory was tested 2 and 6 weeks after anesthesia. RESULTS Sevoflurane decreased progenitor proliferation and increased cell death until at least 4 days after anesthesia. Spatial reference memory was not affected at 2 weeks but was affected at 6 weeks after sevoflurane administration. CONCLUSION Sevoflurane reduces neurogenesis and increases the death of progenitor cells in developing brain. This might mediate the late-onset neurocognitive outcome after sevoflurane application.
Collapse
Affiliation(s)
- Fang Fang
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | | | | |
Collapse
|
17
|
Modulation of neuroplasticity pathways and antidepressant-like behavioural responses following the short-term (3 and 7 days) administration of the 5-HT₄ receptor agonist RS67333. Int J Neuropsychopharmacol 2012; 15:631-43. [PMID: 21733238 DOI: 10.1017/s1461145711000782] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
It has been recently suggested that activation of 5-HT₄ receptors might exert antidepressant-like effects in rats after 3 d treatment, suggesting a new strategy for developing faster-acting antidepressants. We studied the effects of 3 d and 7 d treatment with the 5-HT₄ receptor partial agonist RS67333 (1.5 mg/kg.d) in behavioural tests of chronic efficacy and on neuroplastic-associated changes, such as adult hippocampal neurogenesis, expression of CREB, BDNF, β-catenin, AKT and 5-HT₄ receptor functionality. RS67333 treatment up-regulated hippocampal cell proliferation, β-catenin expression and pCREB/CREB ratio after 3 d treatment. This short-term treatment also reduced immobility time in the forced swim test (FST), together with a partial reversion of the anhedonic-like state (sucrose consumption after chronic corticosterone). Administration of RS67333 for 7 d resulted in a higher increase in the rate of hippocampal cell proliferation, a significant desensitization of 5-HT₄ receptor-coupled adenylate cyclase activity and a more marked increase in the expression of neuroplasticity-related proteins (BDNF, CREB, AKT): these changes reached the same magnitude as those observed after 3 wk administration of classical antidepressants. Consistently, a positive behavioural response in the novelty suppressed feeding (NSF) test and a complete reversion of the anhedonic-like state (sucrose consumption) were also observed after 7 d treatment. These results support the antidepressant-like profile of RS67333 with a shorter onset of action and suggest that this time period of administration (3-7 d) could be a good approximation to experimentally predict the onset of action of this promising strategy.
Collapse
|
18
|
Abstract
Oestradiol exerts a profound influence upon multiple brain circuits. For the most part, these effects are mediated by oestrogen receptor (ER)α. We review here the roles of ERβ, the other ER isoform, in mediating rodent oestradiol-regulated anxiety, aggressive and sexual behaviours, the control of gonadotrophin secretion, and adult neurogenesis. Evidence exists for: (i) ERβ located in the paraventricular nucleus underpinning the suppressive influence of oestradiol on the stress axis and anxiety-like behaviour; (ii) ERβ expressed in gonadotrophin-releasing hormone neurones contributing to oestrogen negative-feedback control of gonadotrophin secretion; (iii) ERβ controlling the offset of lordosis behaviour; (iv) ERβ suppressing aggressive behaviour in males; (v) ERβ modulating responses to social stimuli; and (vi) ERβ in controlling adult neurogenesis. This review highlights two major themes; first, ERβ and ERα are usually tightly inter-related in the oestradiol-dependent control of a particular brain function. For example, even though oestradiol feedback to control reproduction occurs principally through ERα-dependent mechanisms, modulatory roles for ERβ also exist. Second, the roles of ERα and ERβ within a particular neural network may be synergistic or antagonistic. Examples of the latter include the role of ERα to enhance, and ERβ to suppress, anxiety-like and aggressive behaviours. Splice variants such as ERβ2, acting as dominant negative receptors, are of further particular interest because their expression levels may reflect preceeding oestradiol exposure of relevance to oestradiol replacement therapy. Together, this review highlights the predominant modulatory, but nonetheless important, roles of ERβ in mediating the many effects of oestradiol upon adult brain function.
Collapse
Affiliation(s)
- R. J. Handa
- Department of Basic Medical Sciences, University of Arizona College of Medicine - Phoenix, Phoenix, AZ, USA
| | - S. Ogawa
- Laboratory of Behavioral Neuroendocrinology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - J. M. Wang
- Department of Pathology, Pharmacology and Toxicology, Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA
| | - A. E. Herbison
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, Dunedin, New Zealand
| |
Collapse
|
19
|
Satvat E, Gheidi A, Voll S, Odintsova IV, Marrone DF. Location is everything: neurons born during fluoxetine treatment accumulate in regions that do not support spatial learning. Neuropharmacology 2011; 62:1627-33. [PMID: 22182782 DOI: 10.1016/j.neuropharm.2011.11.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Revised: 11/28/2011] [Accepted: 11/30/2011] [Indexed: 12/30/2022]
Abstract
It is well known that antidepressants both improve mood and increase the rate at which the dentate gyrus (DG) generates new neurons. In addition to the implications of neurogenesis for mood regulation, the production and survival of granule cells has also been implicated in learning and memory. Despite this evidence, the results of studies on the effect of antidepressants on memory have been mixed. A critical piece of data that may be missing from previous studies, however, is insight into (a) the location that newborn neurons migrate to following fluoxetine administration and (b) their ability to express normal patterns of activity-related genes. Here we demonstrate a finding that may resolve the discrepancy in the effects fluoxetine-induced neurogenesis on mood and memory: after 5 weeks delay, the net additional neurons generated in animals given the antidepressant fluoxetine during treatment are functionally normal, but preferentially accumulate (due to changes in migration and/or survival) in an area of the DG that is not recruited by spatial memory tasks.
Collapse
Affiliation(s)
- Elham Satvat
- Dept. of Psychology, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada
| | | | | | | | | |
Collapse
|
20
|
Warner TA, Drugan RC. Morris water maze performance deficit produced by intermittent swim stress is partially mediated by norepinephrine. Pharmacol Biochem Behav 2011; 101:24-34. [PMID: 22119910 DOI: 10.1016/j.pbb.2011.11.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 10/18/2011] [Accepted: 11/12/2011] [Indexed: 10/15/2022]
Abstract
Intermittent swim stress (ISS) exposes a rat to cold water and the effects of the procedure produce detrimental results on activity measures 24h later. The ISS model can be used with the Morris water maze (MWM) to investigate the impact of stress on a spatial learning and memory task, known to involve the hippocampus. We investigated if the ISS model produced performance deficits in the MWM (experiments 1 and 2). We also investigated the role of norepinephrine by using an alpha-2 adrenergic agonist (i.e., clonidine) to exacerbate ISS-induced deficits (experiment 3), and using antidepressants (i.e., desipramine and reboxetine) that enhance the synaptic availability of norepinephrine to reduce ISS-induced deficits (experiments 4 and 5). Results indicated a main effect for stress in all experiments, with the exception of experiment 2, as ISS did induce performance deficits in the MWM. Clonidine enhanced ISS-induced deficits only in the learning trials, while desipramine and reboxetine reduced ISS-induced deficits in the learning trials. Additionally, only reboxetine reduced memory deficits in the MWM. These findings provide evidence that norepinephrine may act as a partial mediator of ISS-induced deficits in MWM performance.
Collapse
Affiliation(s)
- Timothy A Warner
- Department of Psychology, University of New Hampshire, Durham, NH, USA.
| | | |
Collapse
|
21
|
Meneses A, Perez-Garcia G, Ponce-Lopez T, Tellez R, Castillo C. Serotonin transporter and memory. Neuropharmacology 2011; 61:355-63. [PMID: 21276807 DOI: 10.1016/j.neuropharm.2011.01.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Revised: 12/15/2010] [Accepted: 01/10/2011] [Indexed: 10/18/2022]
Abstract
The serotonin transporter (SERT) has been associated to diverse functions and diseases, though seldom to memory. Therefore, we made an attempt to summarize and discuss the available publications implicating the involvement of the SERT in memory, amnesia and anti-amnesic effects. Evidence indicates that Alzheimer's disease and drugs of abuse like d-methamphetamine (METH) and (+/-)3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") have been associated to decrements in the SERT expression and memory deficits. Several reports have indicated that memory formation and amnesia affected the SERT expression. The SERT expression seems to be a reliable neural marker related to memory mechanisms, its alterations and potential treatment. The pharmacological, neural and molecular mechanisms associated to these changes are of great importance for investigation.
Collapse
Affiliation(s)
- Alfredo Meneses
- Depto. de Farmacobiología, CINVESTAV-IPN, Tenorios 235, Granjas Coapa, Mexico City 14330, Mexico.
| | | | | | | | | |
Collapse
|
22
|
Experimental Studies on the Role(s) of Serotonin in Learning and Memory Functions. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/s1569-7339(10)70094-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
23
|
McAdam TD, Brien JF, Reynolds JN, Dringenberg HC. Altered water–maze search behavior in adult guinea pigs following chronic prenatal ethanol exposure: Lack of mitigation by postnatal fluoxetine treatment. Behav Brain Res 2008; 191:202-9. [DOI: 10.1016/j.bbr.2008.03.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 03/18/2008] [Accepted: 03/20/2008] [Indexed: 10/22/2022]
|